P

• P chemical symbol, phosphorus; symbol, peta-; position; presbyopia; [L.] proximum (near); pulse; [L.] punctum (point); pupil.

• P₁ parental generation, often homozygous for one or more traits of interest and from which the individuals are used in the first cross of a genetic experiment, producing the next (F1) generation.

• P1,P2,P3 phalanges, numbered from proximal to distal. In horses, called also long pastern (os compedale), short pastern (os coronale), and coffin (os ungulare) bones.

• P₂ second part of the second heart sound (S2) that corresponds to pulmonic valve closure. See heart sounds.

• p53 a tumor suppressor gene active in the cellular response to DNA damage and cell cycle arrest. Called also TP53.

• Pco₂ carbon dioxide partial pressure or tension; also written PCO₂, pCO₂ and pCO₂. See respiration and blood gas analysis.

• Po₂ oxygen partial pressure (tension); also written PO₂, pO₂, and pO₂. See also blood gas analysis.

• p symbol for (1) the short arm of a chromosome; (2) the frequency of the more common allele of a pair; (3) pico-.

• p- symbol, para-.

• Φ phi, capital letter; 21st letter in the Greek alphabet.

• π pi, small letter; 16th letter in the Greek alphabet.

• ϕ phi, small letter; 21st letter in the Greek alphabet.

• Π pi, capital letter; 16th letter of the Greek alphabet.

• Ψ psi, capital letter; 23rd letter in the Greek alphabet.

• ψ psi, small letter; 23rd letter in the Greek alphabet.

• P-450 enzymes superfamily of heme-containing monooxygenase enzymes important for detoxification of drugs, including pesticides, and the biosynthesis of steroid hormones from cholesterol; at high concentrations in some fish-eating birds, e.g., Atlantic puffins.

• p-cresol see cresols.

• P-K reaction Prausnitz-Küstner reaction.

• P mitrale an electrocardiographic abnormality in which the P wave is prolonged, in dogs more than 0.04 s. Associated with left atrial enlargement.

• P pulmonale an electrocardiographic abnormality in which the P wave is tall and peaked. Indicative of right atrial enlargement.

• P site see peptidyl-tRNA binding site (under tRNA).

• Pa chemical symbol, protactinium; symbol, pascal.

• P_aCO₂ symbol for partial pressure of carbon dioxide in the arterial blood. See also blood gas analysis.

• P_aO₂ symbol for partial pressure of oxygen in arterial blood. See also blood gas analysis.

• PA inhibitor plasminogen activator inhibitor.

• Paatsama technique a surgical method for reconstruction of a ruptured cranial cruciate ligament using a strip of fascia lata placed into the joint.

• PAB, PABA para-aminobenzoic acid.

• pabulum food or nourishment.

• paca [pă′k ] a large, plump, ground-dwelling rodent, brown in color, with three to five lines of white spots down the sides of the body. Originated from South and Central America, comprising three species from the genus Cuniculus; Lowland paca (C. paca), Mountain paca (C. taczanowskii), and C. hernandezi.

• pacchionian granulations [pak″e-o′ne- n] enlargements of the arachnoid villi that protrude into the dorsal sagittal sinus; seen well developed in the horse.

• pace an equine gait similar to a trot except that the front and rear limbs on each side are moved in unison instead of the diagonal limbs. A comfortable even gait for the rider, producing an even speed for the duration of a race. Similar to the amble gait but at a fast speed. Many pacing horses are raced and trained in harness. Called also sidewheel.

  • flying p. a natural gait of Icelandic horses.

• pacemaker [pāsma-k r] 1. an object or substance that controls the rate at which a certain phenomenon occurs; often used alone to indicate an artificial cardiac pacemaker; however, there are other natural and artificial pacemakers. 2. In biochemistry, a pacemaker is a substance whose rate of reaction sets the pace for a series of interrelated reactions.

  • asynchronous p. (1) an implanted cardiac pacemaker in which the induced ventricular rhythm is independent of the atrium; it is usually set at a fixed rate of ventricular stimulation.
  • p. cells (1) cells within the heart capable of spontaneous discharge.
  • gastric p. (1) a saddle-shaped area of the greater curvature of the stomach at the junction of its proximal and middle thirds, which regulates the frequency of gastric contractions.
  • phrenic p. (1) a device designed to facilitate respiration by converting radiofrequency signals into electrical impulses that stimulate the phrenic nerve, resulting in contraction and flattening of the diaphragm and improved inspiration of air.
  • p. therapy implantation of a pacemaker device in animals usually for the treatment of symptomatic bradyarrhythmias.
  • p. syndrome falling arterial pressure, low cardiac output and congestive heart failure, usually due to a suboptimal pacing mode.
  • uterine p. either of the two regulating centers that control uterine contractions.
  • wandering p. a condition in which the site of origin of the impulses controlling the heart rate shifts from the head of the sinoatrial node to a lower part of the node or to another part of the atrium. Normal in the dog.

• Pacheco’s disease [p -chek′ōz] a disease of psittacines caused by a psittacid herpesvirus 1 and characterized by weakness, diarrhea, and focal necrosis in the liver and spleen. Intranuclear inclusion bodies in hepatocytes suggest the diagnosis, and confirmed by PCR. The disease causes very heavy mortalities, with sudden death common.

• pachy- word element. [Gr.] thick.

• pachyacria [pak″e-ak′re- ] enlargement of the soft parts of the extremities.

• pachyblepharon [pak″e-blef′ -ron] thickening of the eyelids.

• pachycephaly [pak″e-sef′ -le] abnormal thickness of the bones of the skull.

• pachycheilia [pak″e-ki′le- ] thickening of the lips.

• pachychromatic [pak″e-kro-mat′ik] having the chromatin in thick strands.

• pachydactyly [pak″e-dak′t -le] megalodactyly.

• pachyderma [pak″e-dur′m ] abnormal thickening of the skin.

• pachydermatocele [pak″e-d r-mat′o-sēl] plexiform neuroma attaining large size, producing an elephantiasis-like condition.

• pachyglossia [pak″e-glo′se- ] abnormal thickness of the tongue.

• pachygyria [pak″e-ji′re- ] see macrogyria.

• pachyhematous [pak″e-dur′m -t s] pertaining to or having thickened blood.

• pachyleptomeningitis [pak″e-lep″to-men″in-ji′tis] inflammation of all three meningeal layers.

• pachymeninges [pak″e-m -nin′jēz] dura mater.

• pachymeningitis [pak″e-men″in-ji′tis] inflammation of the dura mater; perimeningitis.

• ossifying p. see dural ossification.

• pachymeningopathy [pak″e-men″in-gop′ -the] noninflammatory disease of the dura mater.

• pachymeninx [pak″e-me′ninks] the dura mater.

• pachynsis [p -kin′sis] an abnormal thickening.

• pachyonychia [pak″e-o-nik′e- ] abnormal thickening of the nails or claws.

• pachyperiostitis [pak″e-per″e-os-ti′tis] periostitis of long bones resulting in abnormal thickness of affected bones.

• pachyperitonitis [pak″e-per″ľ-to-ni′tis] inflammation and thickening of the peritoneum.

• pachypleuritis [pak″e-pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -ri′tis] fibrothorax.

• pachysalpingitis [pak″e-sal″pin-ji′tis] chronic interstitial inflammation of the muscular coat of the oviduct producing thickening; called also mural salpingitis and parenchymatous salpingitis.

• pachysalpingo-ovaritis [pak″e-sal-ping″go-o″v -ri′tis] chronic inflammation of the ovary and oviduct, with thickening.

• pachysomia [pak″e-so′me- ] thickening of parts of the body.

• Pachystigma a genus of South African plants in the family Rubiaceae; the causative toxin is the polyamine toxin, pavetamine, which causes myocarditis and sudden death (gousiekte). Includes P. latifolium, P. pygmaeum, P. thamnus. Called also Vangueira spp., goubos, gousiektebossie.

• pachytene [pak′e-tēn] in prophase of meiosis, the stage following zygotene during which the chromosomes shorten, thicken, and separate into two sister chromatids joined at their centromeres. Paired homologous chromosomes, which were joined by synapsis, now form a tetrad of four chromatids. Where crossing over has occurred between nonsister chromatids, they are joined by Y-shaped chiasmata.

• pachyvaginalitis [pak″e-vaj″ľ-n l-i′tis] inflammation and thickening of the tunica vaginalis of the testis.

• pachyvaginitis [pak″e-vaj″ľ-ni′tis] chronic vaginitis with thickening of the vaginal walls.

• Pacifastacus leniusculus American crayfish; signal crayfish.

• Pacific Coast tick see Dermacentor occidentalis.

• pacing [pās′ing] 1. normal gait of some horses. See pace. 2. stereotyped pacing; a habit in all caged animals, especially if they are active species and are confined in very small areas. May cause excessive wear in footpads, in snakes the damage is usually to the front of the head. 3. setting the pace or rate of movement. See cardiac pacing.

• pacinian corpuscle [p -sin′e- n] cutaneous mechanoreceptor that senses pressure and stretch.

• pack [pak] 1. a sterile surgical pack usually made from cotton and used to temporarily fill a cavity to achieve hemostasis. 2. jute container (13.5 cm × 7.5 cm × 7.5 cm) into which wool is packed to make a bale; other similar containers in which wool is packed include butts and sacks. 3. social unit that hunts, rears its young, and protects a communal territory as a group. 4. term used to describe the degree of compaction of silage. A major factor determining the nutritive value of silage. Low porosity in tightly compacted silage reduces O₂ diffusion, limiting aerobic deterioration. High porosity in low packing density silage is a major cause of loss of sugar content. Packing in bunker silage usually achieved by repeatedly driving a tractor over the top surface during filling.

• packed cell volume (PCV) the percentage of the volume of whole, unclotted blood occupied by the erythrocytes. A useful prognostic indicator in dehydration when the PCV rises markedly.

• packer 1. an instrument for introducing a dressing into a cavity or a wound. 2. proprietor of a meat packing plant.

• packet knot slip knot; useful for the beginning of a continuous suture.

• packing [pak′ing] 1. the filling of a wound or cavity with gauze, sponge, or other material. 2. the material used for this purpose.

• packing plant [pak′ing] see meat packing plant.

• paclitaxel [pak″lľ-tak′s l] an anti-cancer agent derived from the western yew tree (Taxus baccata).

• PACSPicture Archiving and Communication System; a computer system of hardware and programs for the storage, display, transfer, archival, and communication system of radiographic and other diagnostic images.

• pad [pad] a cushion-like mass of soft material that may be (1) anatomical; (2) surgical.

  • abdominal p. a pad for the absorption of discharges from abdominal wounds, or for packing off abdominal viscera to improve exposure during surgery.
  • communal p. metacarpal pad.
  • fat p. a pad of fat lying within a joint, covered with synovial membrane and thought to assist in the spreading of synovial lubricant, e.g., infrapatellar fat pad of stifle joint.
  • foot p’s see footpad.
  • Mikulicz’s p. a pad made of folded gauze, for packing off viscera in surgical procedures.
  • pressure p. in surgery, gauze sponges used to apply pressure in the control of minor hemorrhage.
  • stripped p. abrasion of the pad with exposure of the sensitive deep epidermis, dermis or occasionally underlying fibroadipose tissue. A common injury in Greyhounds that have raced on asphalt or been overexercised on a walking machine with a rough belt.

• pad-saddle a thick pad of felt made like a saddle but without a tree. Can be made in leather with a minor arch. Used for riding horses in track work.

• paddock a fenced field or enclosure.

  • joining p. used for mating.

• PAE postantibiotic effect.

• pae- for words beginning thus, see also those beginning pe-.

• Paecilomyces a genus of soil fungi in the phylum Ascomycota that are sometimes found as contaminants of the skin and oral mucosa. See also hyalohyphomycosis.

  • P. fumosoroseus associated with cutaneous and disseminated infections in dogs and cats. Now classified as Isaria fumosorosea.
  • P. varioti an opportunistic fungal pathogen of the respiratory tract of birds.

• paecilomycosis infection with fungi in the genus Paecilomyces.

• Paenibacillus larvae gram-positive spore forming bacillus. The cause of American foulbrood in honeybees. Previously classified as Bacillus larvae and as Paenibacillus larvae subspecies larvae.

• PAF platelet activating factor.

• Pagrus auratus finfish in family Sparidae. Called also snapper, silver sea bream.

• -pagus word element. [Gr.] conjoined twins.

• PAH, PAHA para-aminohippuric acid.

• pail-fed said of neonates reared on milk or replacer fed from a pail instead of a bottle. Called also bucket-fed.

• pail-feeding a method of rearing calves by weaning them off the dam and feeding them on her or another cow’s milk or milk replacer in a bucket without the use of a nipple. Because of the common practice of feeding at too long intervals with cold milk, there is a higher prevalence of dietary diarrhea in pail-fed calves than in calves that are suckled. See also dietary diarrhea.

• pain [pān] an apparently noxious sensory experience that causes an animal to move or adopt protective behaviors in order to avoid or reduce or eliminate its intensity All receptors for pain stimuli are free nerve endings of groups of myelinated or unmyelinated neural fibers abundantly distributed in the superficial layers of the skin and in certain deeper tissues such as the periosteum, surfaces of the joints, arterial walls, and the falx and tentorium of the cranial cavity. The distribution of pain receptors in the gastrointestinal mucosa apparently is similar to that in the skin; thus, the mucosa is quite sensitive to irritation and other painful stimuli. Although the parenchyma of the liver and the alveoli of the lungs are almost entirely insensitive to pain, the liver as an organ and the bile ducts are extremely sensitive, as are the bronchi, ureters, parietal pleura, and peritoneum. Some pain receptors are selective in their response to stimuli, but most are sensitive to more than one of the following types of excitation: (1) mechanical stress of trauma; (2) extremes of heat and cold; and (3) chemical substances, such as histamine, potassium ions, acids, prostaglandins, bradykinin, and acetylcholine. The conscious perception of pain probably takes place in the thalamus and lower centers; interpretation of the quality of pain is probably the role of the cerebral cortex. There are some naturally occurring internal systems in the body that are known to control pain but none of them has been completely verified. One of the best known is the gate control system in which it is thought that pain impulses are mediated in the substantia gelatinosa of the spinal cord.

  • abdominal p. pain occurring in the area between the thorax and pelvis. Manifestations vary between species. Identifiable syndromes include: (1) horse—pawing, flank watching, rolling, straddling as though to urinate, lying on the back; (2) cattle—may depress back and paddle with hindfeet but mostly arched back, grunting, immobility; (3) dogs and cats—arched back, grunting, depression, reluctance to move. Sometimes there is elevation of the hindquarters, with the chest and forelegs on the ground (the so-called ‘praying dog’ attitude).
  • Beagle p. syndrome see steroid responsive meningitis-arteritis. endogenous p. caused by factors within the body, e.g., stretching of mesentery.
  • p. hypersensitivity responsiveness to noxious stimuli that produces exaggerated and prolonged pain. May be either peripheral sensitization, which is a reduction in threshold and an increase in responsiveness of the peripheral ends of nociceptors, or central, which is an increase in the excitability of neurons within the central nervous system.
  • projected p. lesions in one area can affect the nerve supply to a distant area in which pain is experienced.
  • p. receptors free nerve endings of tufts of fine points or buttons.
  • referred p. pain felt in an area distant from the site of disease but not mediated through a common innervation. There is no evidence that referred pain occurs in animals but it seems likely on anatomical grounds.
  • p. threshold the lowest level at which a stimulus can be applied and cause perceptible pain.
  • p. tolerance the level of stimulation at which pain becomes intolerable.
  • visceral p. caused by inflammation of serous surfaces, distention of viscera and inflammation or compression of peripheral nerves. The pain caused by stretching of the wall of a hollow viscus is often intermittent because of its alternating relaxation and spasm in response to distention.

• paint [pānt] commercial paint products are used in animal accommodation. Most contain some lead, even so-called lead-free paints. See lead¹ poisoning.

• paint horse [pānt] see American Paint horse.

• paintbrushes see Castilleja.

• paired pertaining to data or animals that are matched as being very similar.

  • p. controls see paired control.
  • p. data values which fall normally into pairs and can therefore be expected to vary more between pairs than within pairs.

• Pajaroello tick see Ornithodorus coriaceus.

• pakoein a toxic cycad glycoside found in Bowenia, Cycas etc.

• palae(o)- for words beginning thus see pale(o)-.

• palatability pleasantness of taste of feed; willingness of animals to eat the feed in preference to others, which may be based on factors other than taste, e.g., smell, appearance, the sound of cows munching on ensilage.

• palate [pal′ t] the roof of the mouth. The front portion braced by the upper jaw bones (maxillae) is known as the hard palate and forms the partition between the mouth and the nose. The fleshy part arching from the hard palate to the throat is called the soft palate and separates the oropharynx from the nasopharynx. When the animal swallows, the rear of the soft palate swings up against the back of the pharynx and blocks the passage of food and air to the nose. See also soft palate.

  • cleft p. see cleft lip, cleft palate.
  • displaced p. the soft palate of the horse, except during deglutition, rests below the epiglottis. It may be displaced and come to lie above the epiglottis, due either to hypoplasia of the epiglottis or paresis of the soft palate.
  • midline defect of p. see cleft lip.
  • p. reflexes swallowing caused by stimulation of the palate.

• palatine, palatal pertaining to the palate. See also palate.

  • p. abscess commonly diagnosed in companion birds. Are often accumulations of keratinized cellular debris as a result of a dietary deficiency of vitamin A.
  • p. fissure narrow gap beside the palatine process of the incisive bone; covered by the vomeronasal organ and pierced by the naso-incisive duct.
  • p. sinus one of the paranasal sinuses connecting with the nasal cavity that is particularly large in ruminants.
  • p. slit the caudal half of the palate in birds is divided by a median choanal slit.

• palatitis [pal″ -ti′tis] inflammation of the palate.

• palat(o)- word element. [L.] relationship to the palate.

• palatoglossal [pal″ -to-glos′ l] pertaining to the palate and tongue.

  • p. arch the thick fold of tissue passing from the soft palate to the lateral border of the tongue.

• palatognathous [pal″ -tog′n-th s] having a congenitally cleft palate.

• palatomaxillary [pal″ -to-mak′sľ-lar″e] pertaining to the palate and maxilla.

• palatopharyngeal [pal″ -to-f-rin′je- l] pertaining to the palate and pharynx.

  • p. arch a horizontal fold of pharyngeal mucosa that passes from the soft palate and joins with its contralateral fold over the entrance to the esophagus at the intrapharyngeal ostium; it marks the division between the nasopharynx above and the oropharynx below.

• palatoplasty [pal′ -to-plas″te] plastic reconstruction of the palate.

• palatoplegia [pal″ -to-ple′j] paralysis of the palate.

• palatorrhaphy [pal″ -tor′ -fe] surgical correction of a cleft palate by suturing.

• palatoschisis [pal″ -tos′kľ-sis] cleft palate.

• palatoversion a dental malocclusion in which a tooth is in its anatomically correct position in the dental arch but is abnormally angled in a palatal direction.

• palatum [p -la′t m] [L.] palate.

• pale lacking the pink color of normal viable tissue that is perfused with blood.

• pale soft exudative pork see porcine stress syndrome.

• pale(o)- word element. [Gr.] relationship to old.

• paleocerebellum [pa″le-o-ser″ -bel′ m] originally, the phylogenetically older parts of the cerebellum; the term is now applied specifically to those parts whose afferent inflow is predominantly supplied by spinocerebellar fibers.

  P-01.

  

  Paint horse

• paleocortex [pa″le-o-kor′teks] paleopallium.

• paleoencephalon the (phylogenetically) old brain; all of the brain except the cerebral cortex and its dependences.

• paleogenetic [pa″le-o-j -net′ik] originated in the past; not newly acquired; said of traits, structures, etc., of species.

• paleokinetic [pa″le-o-kľ-net′ik] old kinetic; a term applied to the nervous motor mechanism concerned in automatic associated movements.

• paleopallium [pa″le-o-pal′e- m] that part of the pallium (cerebral cortex) developing with the archipallium in association with the olfactory system; it is phylogenetically older and less stratified than the neopallium, and composed chiefly of the piriform cortex and parahippocampal gyrus. Called also paleocortex.

• paleopathology [pa″le-o-p -thol′ -je] study of disease in bodies that have been preserved from ancient times.

• paleopulmo [pa″le-o-pul′mo] the functional division of the avian respiratory tract formed by the parabronchi arising from the mediolateral and medioventral bronchi.

• paleostriatum [pa″le-o-stri-a′t m] the phylogenetically older portion of the corpus striatum, represented by the globus pallidus.

• paleothalamus [pa″le-o-thal′ -m s] the phylogenetically older part of the thalamus, i.e., the medial portion that lacks reciprocal connections with the neopallium.

• Palicourea [pal″ľ-ko-u′re- ] South American plant genus in the family Rubiaceae; contain fluoroacetate, a cause of myocardial damage and sudden death; includes P. aeneofusca, P. grandiflora, P. juruana, P. marcgravii, cafezinho, cafe bravo, erva cafe, erva de rato, roxa, roxinha, roxona, vick.

• pali(n)- word element. [Gr.] again, pathological repetition.

• palindrome [pal′in-drōm] literally, something that reads the same backward as forward. In nucleic acid biochemistry, a segment of double-stranded DNA in which the nucleotide sequence of one strand runs in opposite order to that of the complementary strand. Palindromic sequences of 4–10 or more base pairs occur not infrequently. These function as recognition sites for cleavage by restriction endonuclease enzymes or secondary structures as the folding of RNA molecules or the hairpin structures found at the termini of the single-stranded DNA genomes of parvoviruses.

  • interrupted p. restriction enzymes such as BglI recognize sequences that are interrupted palindromes, e.g., GCCNNN↓NGGC where N is any nucleotide.

• palindromia [pal″in-dro′me- ] a recurrence or relapse.

• palisade worms [pal″ľ-sād′] see Strongylus.

• palisading giving the appearance of palisades, as in a picket fence.

  • p. crust alternating horizontal layers of keratin and exudate in a crust or scab.
  • p. granuloma see palisading granuloma.

• palladium (Pd) [p -la′de- m] a chemical element, atomic number 46, atomic weight 106.4.

• palliate [pal′e-āt] to relieve clinical signs without treating the underlying cause of the disease.

• palliative [pal′e- -tiv] affording relief without treating the underlying cause of the disease; e.g., providing pain relief to a patient with terminal cancer; also, a drug that so acts.

• pallidum [pal′ľ-d m] the globus pallidus, the medial subdivision of the lentiform nucleus, of the brain.

• pallium [pal′e- m] the cerebral cortex viewed in its entirety, i.e., the mantle of gray matter covering both cerebral hemispheres. Also, the cerebral cortex during its development.

• pallor [pal′ r] paleness, as of the skin or mucosae. Although it is commonly associated with anemia, many long-term cases show mucosae of normal color; pallor is also a common sign in shock.

  • central p. the lighter staining central area seen in discoid-shaped erythrocytes of dogs.

• palm [pahm, pahlm] one of many flowering plants in the family Arecaceae (Palmae); including Elaeis guineensis (oil palm), Phoenix dactylifera (date palm), Cocus nucifera (coconut palm), Caryota mitis (fishtail palm), Metroxylon sagu (sago palm). See also sago palm.

• Palma christi [pahl′m ] see Ricinus communis.

• palmar [pahl′m r] descriptive of the palm of the human hand, or of the homologous surface or direction of the limbs of other animal species.

  • p. nerve block see plantar block.

• palmar-plantar erythrodysesthesia syndrome [pahl′m r] a side effect of some chemotherapy drugs caused by capillary leakage of the drug into tissues, particularly the hands and feet in humans and the paws or feet in animals. Tissue damage results in redness, swelling, and blisters. Tingling or burning is reported in humans.

• Palmer dental notation [pahl′m r] a scheme for charting the position and number of teeth. A horizontal line indicates the occlusal plane and a vertical line in the middle indicates the midline. The teeth in each quadrant are numbered, starting from the point closest to the midline.

• palmitate [pal′mľ-tāt] salt or ester of palmitic acid.

• palmitic acid [pal-mit′ik] a 16-carbon saturated fatty acid from animal and 16-carbon vegetable fats, particularly palm oil.

• palmitin [pal′mľ-tin] glycerol tripalmitate, one of the common fats in animal fat. A crystallizable and saponifiable substance.

• palmitoleic acid [pal″mľ-to-le′ik] a 16-carbon monounsaturated fatty acid, with a double bond at carbons 7,8. An endogenously synthesized nonessential fatty acid.

• palmityl-CoA-carnitine transferase an enzyme involved in the transport of fatty acids across the mitochondrial membrane.

• palmus [pa′m s] 1. palpitation. 2. clonic spasm of limb muscles, producing a jumping motion.

• palo santo tree see Bulnesia sarmientii.

• palomino [pal-o-me′no] 1. in horses, not a breed, but a color type of gold with white mane and tail. 2. a breed of domestic rabbit characterized by its gold- or lynx-colored fur.

• palpable [pal′p -b l] perceptible by touch.

• palpate [pal′pāt] to perform palpation.

• palpation [pal-pa′sh n] the technique of examining parts of the body by touching and feeling them.

  • abdominal p. palpation of the contents of the abdomen and the state of the abdominal wall either through the wall or per rectum.
  • digital p. method of physical examination of a patient using a finger.
  • gastric p. internal palpation of the stomach via the esophagus is performed in dolphins and other cetaceans.
  • motion p. in chiropractic, examination of the range of movement in vertebral joints.
  • per-rectal p. palpation of the posterior abdomen and the organs in it by inserting the finger (in dogs) or hand and arm (in horses, cattle, and pigs) in the rectum. Called also rectal palpation.
  • pharyngeal p. palpation via the external wall in small animals; can be performed per os in cattle but requires a mouth speculum for all but the most deft practitioners.
  • static p. in chiropractic, examination of the vertebral column for alignment and asymmetry and surrounding soft tissues for tone, heat, and pain while the patient is stationary.

• palpebra [pal′p -br] pl. palpebrae [L.] eyelid.

• palpebra tertia [pal′p -br] third eyelid, palpebra III; membrana nictitans.

• palpebral [pal′p -br l] pertaining to the eyelid.

  • p. conjunctiva conjunctiva lining the inner aspect of the eyelid.
  • p. commissure see canthus.
  • p. fissure see palpebral fissure.
  • medial p. ligament the medial canthal ligament that connects the medial canthus to the orbit.
  • p. nerve a branch of the auriculopalpebral nerve that innervates the orbicularis oculi muscle of the eyelid and effects eyelid closure. See Table 13.
  • p. reflex eyelid closure following stimulation of the periocular tissue; requires normal function of cranial nerves V and VII, as well as the orbicularis oculi muscle.

• palpebritis [pal″p -bri′tis] blepharitis.

• PALS periarteriolar lymphoid sheath. See white pulp.

• palsy [pawl′ze] paralysis. A word used commonly in human medicine but rarely if ever in veterinary medicine.

  • Bell’s p. paralysis of the facial nerve of unknown cause, seen in people. A similar condition occurs in dogs, referred to as idiopathic facial nerve paralysis.

• palustrine a toxic alkaloid in Equisetum spp.

• Palyam viruses a group of viruses in the genus Orbivirus that cause abortion and congenital abnormalities, including hydranencephaly and cerebellar hypoplasia, in cattle in Africa, Japan, China, and Australia.

• PAM, 2-PAM 2-pyridine aldoxime methchloride (pralidoxime chloride).

• pamidronate [pam″ľ-dro′nāt] a bisphosphonate used in the management of hypercalcemia and to alleviate osteolytic pain of osteosarcomas in dogs.

• pampas grass see Cortaderia selloana.

• pampiniform shaped like a tendril, e.g., pampiniform plexus, a plexus of veins that tangle around the tortuous testicular artery.

• PAMSp aminosalicylic acid.

• pan- word element. [Gr.] all.

• panacea [pan″ -se′] a remedy for all diseases; a “cure-all”; in Greek mythology Panacea was the goddess of universal remedy.

• panagglutinin [pan″ -gloo′tľ-nin] an agglutinin that agglutinates the erythrocytes of all human blood groups.

• panangiitis [pan″an″je-i′tis] inflammation involving all the coats of a vessel.

• panarteritis nodosa [pan″ahr″t -ri′tis no-dōs′] see periarteritis nodosa.

• panarthritis [pan″ahr-thri′tis] inflammation of all the joints.

• panatrophy [pan-at′r -fe] atrophy of several parts; diffuse atrophy.

• panautonomic [pan″aw-t -nom′ik] pertaining to or affecting the entire autonomic (sympathetic and parasympathetic) nervous system.

• pancarditis [pan″kahr-di′tis] diffuse inflammation of the heart.

• pancolectomy [pan″ko-lek′t -me] excision of the entire colon, with creation of an outlet from the ileum on the body surface.

• pancreas [pan′kre- s] a large, elongated, racemose gland located in the anterior abdomen between the liver, kidneys, stomach, spleen, and duodenum. The pancreas is composed of both exocrine and endocrine tissue. The acini secrete digestive enzymes, and small ductules leading from the acini secrete ions, mainly sodium and bicarbonate. The combined product, pancreatic juice, enters a long pancreatic duct and from there is transported duct to the duodenum. The pancreatic juice contains enzymes for the breakdown of proteins, carbohydrates, and fats. The bicarbonate ions in the pancreatic secretion help neutralize the acidic chyme that is passed along from the stomach to the duodenum. The endocrine functions of the pancreas are related to the islets of Langerhans that occur throughout the pancreas. These small islands contain three major types of cells: the alpha, beta, and delta cells. The alpha cells secrete the hormone glucagon, which elevates blood sugar. The beta cells secrete insulin, which affects the metabolism of carbohydrates, proteins, and fats. The delta cells secrete somatostatin, the functions of which inhibits the secretion of both glucagon and insulin and may act as a controller of metabolic processes. The somatostatin produced by the delta cells of the pancreas is the same as that produced by the hypothalamus as an inhibitor of the release of growth hormone from the pituitary gland.

  • p. disease pancreatic atrophy of postsmolt Atlantic salmon caused by a togavirus infection; clinical signs include anorexia, emaciation. Called also sleeping disease.

• pancreatectomy [pan″kre- -tek′t -me] excision of the pancreas.

• pancreatic [pan″kre-at′ik] pertaining to the pancreas. See also pancreas, pancreatitis, diabetes mellitus.

  • p. abscess occurs as a complication of acute pancreatitis or subsequent to pancreatic surgery due to bacterial contamination but is most common as an extension from a leaking gastric ulcer.
  • p. acinar atrophy the islets of Langerhans remain normal but acinar tissue atrophies and exocrine function is compromised. Seen most commonly in large breeds of dogs, particularly German shepherds and Collies. Clinical signs are related to the exocrine pancreatic insufficiency (see below).
  • acute p. necrosis see acute hemorrhagic pancreatitis.
  • p. alpha cells alpha cells cells in the islet of Langerhans which secrete glucagon.
  • p. anomaly includes acinar hypoplasia and congenital Islet of langerhans aplasia.
  • p. beta cells beta cells comprise the majority of pancreatic islet cell population; secrete insulin.
  • p. bladder a diverticulum in the pancreatic duct like a gallbladder in the bile duct. Seen in some cats.
  • p. calculus small concretions, 4–5 mm diameter, in the pancreatic ducts, caused by chronic inflammation. Seen, usually in large numbers, in cattle.
  • p. cysts anomalous obstructions of ducts, often associated with similar cysts in kidneys and bile ducts.
  • p. delta cells cells in the islet of Langerhans; known to secrete somatostatin.
  • p. duct one of the two excretory ducts of the pancreas. Depending on the species, it may unite with the common bile duct before entering the duodenum at the major duodenal papilla. Absent from the pig and ox that only have an accessory pancreatic duct (developed from the dorsal primordium) that opens on the minor duodenal papilla. See also bile duct.
  • p. duct obstruction congenitally by agenesis of the duct, by pancreatic lithiasis or inflammation or neoplasia in the vicinity; causes initial distention followed by atrophy of acinar tissue.
  • p. ectopic tissue small masses of pancreatic exocrine or endocrine tissue found occasionally in the wall of the stomach or intestines and in the gallbladder; presumed to be functional.
  • p. enzymes 1. the exocrine secretion into the intestine includes amylase, endo- and exopeptidases, and lipase. The endopeptidases include trypsin, chymotrypsin, and elastase, the exopeptidases are the carboxypeptidases A and B. 2. preparations of various pancreatic extracts are used as enzyme replacement therapy in the clinical management of exocrine pancreatic insufficiency in dogs and cats.

    P-02.

    

    Assessing the palpebral reflex by lightly tapping the medial or lateral canthus

  • exocrine p. insufficiency (EPI) insufficient secretion of digestive enzymes, usually due to loss of pancreatic acinar tissue from idiopathic acinar atrophy or acute or chronic inflammation; causes maldigestion and malabsorption with diarrhea, steatorrhea, and weight loss.
  • p. F cells secrete pancreatic polypeptide; called also PP cells.
  • p. fibrosis a sequel to pancreatitis, pancreatic duct obstruction, zinc poisoning.
  • p. gastrinoma a gastrin-producing tumor arising from the delta cells of the pancreatic islets that causes hypergastrinemia, hypersecretion of gastric acid, and ulceration of the upper gastrointestinal tract. Occurs rarely in dogs. See also Zollinger-Ellison syndrome.
  • p. hypertrophy physiological response to diets high in protein and energy.
  • p. islets islets of cells scattered through the pancreas; contain alpha, beta, C, and D cells.
  • p. islet cell tumor see gastrinoma, insulinoma.
  • p. lipase enzyme released from the exocrine pancreas; catalyzes the hydrolysis of dietary lipids in the presence of bile salts. See also lipase.
  • p. lithiasis see pancreatic calculus (above).
  • p. nodular hyperplasia firm, pale elevations on the surface of the gland; involve only the exocrine tissue; common in old cats and dogs; cause unknown; no discernible effect on patient.
  • p. polypeptide secreted by the PP cells in the pancreas; regulates endocrine and exocrine pancreatic secretion.
  • p. trypsin inhibitor see trypsin inhibitor.

• pancreatic(o)- [pan″kre-at′ik] word element. [Gr.] pertaining to the pancreas or the pancreatic duct.

• pancreaticoduodenal [pan″kre-at″ľ-ko-doo″o-de′n l] pertaining to the pancreas and duodenum.

• pancreaticoenterostomy [pan″kre-at″ľ-ko-en″t r-os′t -me] anastomosis of the pancreatic duct to the intestine.

• pancreaticomesojejunal ligament [pan″kre-at″ľ-ko-me″zo-j -joo′n l] an anomalous structure that extends between the pancreaticoduodenal vein, under the ileum and colon, to the left side of the mesojejunum. Reported to be a cause of chronic diarrhea and abdominal distention in kittens.

• pancreatin [pan′kre- -tin] a substance from the pancreas of the pig or ox containing digestive enzymes, principally amylase, protease, and lipase; used in the treatment of pancreatic exocrine insufficiency.

• pancreatitis [pan″kre- -ti′tis] inflammation of the pancreas; an important disease in dogs and cats.

  • acute hemorrhagic p. a condition due to autolysis of pancreatic tissue caused by escape of enzymes into the substance, resulting in hemorrhage into the parenchyma and surrounding tissues. Seen most commonly in dogs, rarely in horses and pigs. Clinical signs include abdominal pain that may be severe and associated with cardiovascular shock, vomiting, and diarrhea. Fatalities are not uncommon. In the longer term, the process may be slowly progressive, appearing clinically to be relapsing, often with eventual destruction of the islets of Langerhans that leads to diabetes mellitus. Called also acute pancreatic necrosis.
  • chronic p. relapsing or continuing acute pancreatic necrosis. Called also relapsing pancreatitis.
  • focal p. focal lesions discovered incidentally in patients dying of other disease, e.g., canine distemper, foot and mouth disease.
  • interstitial p. inflammation of the interstitial tissue; may be acute or chronic.
  • necrotizing p. see acute hemorrhagic pancreatitis (above).
  • relapsing p. see chronic pancreatitis (above).

• pancreat(o)- word element. [Gr.] pertining to the pancreas.

• pancreatoduodenectomy [pan″kre- -to-doo″o-d-nek′t -me] excision of the head of the pancreas along with the encircling loop of the duodenum.

• pancreatogenous [pan″kre- -toj′-n s] arising in the pancreas.

• pancreatolithectomy [pan″kre- -to-lľ-thek′t -me] excision of a calculus from the pancreas.

• pancreatolithiasis [pan″kre- -to-lľ-thi′ -sis] the presence of calculi in the ductal system or parenchyma of the pancreas.

• pancreatolithotomy [pan″kre- -to-lľ-thot′ -me] incision of the pancreas for the removal of calculi.

• pancreatolysis [pan″kre- -tol′ľ-sis] destruction of pancreatic tissue.

• pancreatotomy [pan-kre-at′ -me] incision of the pancreas.

• pancreatotropic [pan″kre- -to-tro′pik] having a special affinity for the pancreas.

• pancrelipase [pan″kre-li′pās] a preparation of pig pancreas containing enzymes, principally lipase with amylase and protease, having the same digestive actions as pancreatic juice; used in the treatment of exocrine pancreatic insufficiency.

• pancreolithotomy [pan″kre-o-lľ-thot′ -me] pancreatolithotomy.

• pancreolysis [pan″kre-ol′ľ-sis] pancreatolysis.

• pancreozymin [pan′kre-o-zi″min] a hormone of the duodenal mucosa that stimulates the external secretory activity of the pancreas, especially its production of amylase; identical with cholecystokinin.

• pancuronium [pan″ku-ro′ne- m] a nondepolarizing neuromuscular blocking agent, used as the bromide salt.

• pancystitis [pan″sis-ti′tis] cystitis involving the entire thickness of the wall of the urinary bladder, as occurs in interstitial cystitis.

• pancytopenia [pan″si-to-pe′ne- ] abnormal depression of all the cellular elements of the blood. Results from the depression of activity of bone marrow, spleen, and lymph nodes such as occurs in radiation injury and a number of poisonings, e.g., Pteridium aquilinum, trichlorethylene extracted soybean meal, nitrofurans, and stachybotrytoxicosis.

  • aplastic p. see aplastic anemia.
  • bovine neonatal p. occurs in calves less than 4 weeks of age receiving colostrum from a cow immunized with a bovine viral diarrhea virus (BVDV) vaccine produced using allogenic cell lines that result in vaccine-induced alloantibodies in colostrum to major histocompatibility class 1 antigens, leading to thrombocytopenia and widespread internal hemorrhage; called also bleeding calf syndrome, neonatal hemorrhagic diathesis, blood sweating disease.
  • myelophthisic p. resulting from loss of bone marrow function secondary to crowding out of marrow precursors.
  • tropical canine p. (TCP) see canine ehrlichiosis.

• pancytopenic relating to pancytopenia.

• panda includes the giant panda and red panda (see below).

  • giant p. (Ailuropoda melanoleuca) in the family Ursidae; native to central China, it has a large bear-like body and short tail. The distinctive black and white coat is widely recognized because of the attention this animal receives in zoo exhibits and media accounts of conservation efforts. Also known as the panda bear, or panda, it is eats almost exclusively bamboo despite a digestive system of a carnivore.
  • red p. (Ailurus fulgens) the only living member of the family Ailuridae; not closely related to the giant panda (Ailuropoda melanoleuca), which is in the family of true bears, Ursidae. Native to the Himalayas and southwestern China, it is medium-sized with a dense, red and black coat, and long, furry, ringed tail. Called also lesser panda, cat bear. Diet of mostly bamboo but also small mammals, birds, eggs, and plant material.

• pandemic [pan-dem′ik] a widespread epidemic, i.e., the disease is clustered in time but not in space.

• Pandy test a screening test for globulin in the cerebrospinal fluid; a positive result is an indication of inflammation in the central nervous system.

• panencephalitis [pan″ n-sef″ -li′tis] encephalitis with parenchymatous lesions of both the gray and white matter of the brain.

  • sclerosing p. see old dog encephalitis.

• panendoscope [pan-en′do-skōp] a cystoscope that gives a wide-angle view of the urinary bladder.

• Paneth cell narrow, pyramidal or columnar epithelial cell with a nucleus close to its base. Found in the fundus of the mucosal crypts in the intestine.

• pangenesis a now discarded hypothesis about heredity stating that the whole organism reproduces itself through all of its parts. The proposed mechanism is based on the supposed existence of gemmules which were shed by all cells in an organism into the blood. Gemmules supposedly circulated throughout the body and finally congregated in the gonads to be inherited by an offspring.

• pangola grass Digitariadecumbens. D. eriantha.

• Pangonia [pan-go′ne- ] a genus of flies in the family Tabanidae; some feed on blood and cause insect worry in horses and cattle. Called also deer fly. Do not suck blood but will mop up spilled blood.

• panhypopituitarism [pan-hi″po-pľ-too′ľ-t -riz- m] generalized hypopituitarism due to absence or damage to the pituitary gland, which in its complete form, leads to absence of gonadal function and insufficiency of thyroid and adrenal function. When cachexia is a prominent feature, it is called Simmonds’ disease or pituitary cachexia.

  P-03.

  

  Anatomy of pancreatic islets

  • juvenile p. most frequent in German shepherd dogs where it is an autosomal recessive inherited trait but also occurs in other breeds; puppy dwarfism is not apparent until 2–3 months old; small stature, delayed dentition, retained puppy coat, progressive alopecia, infantile genitalia, and short life span are characteristic. See also German shepherd dog dwarfism.

• panhysterectomy [pan″his-t r-ek′t -me] total hysterectomy.

• panhysterosalpingectomy [pan-his″t r-o-sal″pin-jek′t -me] excision of the uterus, cervix, and oviducts.

• panhysterosalpingo-oophorectomy [pan-his″t r-o-sal″ping-go-o″of--rek′t -me] excision of the uterus, cervix, uterine tubes (oviducts), and ovaries.

• panic grass [pan′ik] grasses that are members of the genus Panicum, e.g., P. antidotale.

  • bambatsi p.g.P. coloratum var. makarikariense.
  • blue p.g.P. antidotal.
  • giant p.g. see Brachiaria mutica.
  • green p.g.Megathyrsus maximum var. pubiglumis (P. maximum var. trichoglume).
  • hairy p.g.P. effusum.

• Panicum [pan′ľ-kum] a genus of grasses in the family Poaceae. May contain sufficient nitrate or soluble oxalate to cause poisoning with these substances. They are highly productive and popular annual and perennial grasses and cereal crops, but many of themcause hepatogenous photosensitization due probably to a high content of steroidal saponins in the plants. Edematous enlargement and icteric staining of the cranial tissues gives rise to the common names of yellow bighead and yellow thickhead. Some contain calcium oxalate crystals and cause equine nutritional secondary hyperparathyroidism. See also Megathrysus.

  • P. anticumBrachiaria mutica.
  • P. antidotale may contain sufficient oxalate to cause oxalate poisoning in sheep or osteodystrophia in horses. Also reported as a cause of atypical interstitial pneumonia. Called also blue panic grass.
  • P. capillare causes nitrate–nitrite poisoning; called also witchgrass.
  • P. coloratum may contain high oxalate or cause hepatogenous photosensitization. Called also Coolah grass, kleingrass.
  • P. crus-galli reputed to cause photosensitization.
  • P. decompositum suspected high concentrations of steroidal saponins causing hepatogenous photosensitization. Called also native millet (Australia).
  • P. dichotomiflorum causes hepatogenous photosensitization due to steroidal saponins; called also smooth witchgrass.
  • P. effusum causes hepatogenous photosensitization due probably to steroidal saponins. Called also hairy millet.
  • P. gilvum causes hepatogenous photosensitization due to steroidal saponins. Called also P. laevifolium var. contractum, P. schinzii, sweet grass.
  • P. maximum see Megathyrsus.
  • P. miliaceum an annual cereal crop. Causes hepatogenous photosensitization due probably to steroidal saponins. Called also French millet.
  • P. muticum Brachiariamutica.
  • P. purpurascens a coarse, high-producing pasture grass. Called also para grass.
  • P. queenslandicum causes hepatogenous photosensitization due probably to steroidal saponins. Called also Yabila grass.
  • P. virgatum causes hepatogenous photosensitization due probably to steroidal saponins.
  • P. whitei causes hepatogenous photosensitization due probably to steroidal saponins. Called also P. laevinode, pepper grass.

• panimmunity [pan″ľ-mu′nľ-te] immunity to a wide range of bacterial and viral infections.

• panleukopenia [pan″loo-ko-pe′ne- ] 1. abnormal depression in numbers of white blood cells. 2. the name of a disease caused by feline parvovirus; see feline panleukopenia.

  • feline p. virus feline parvovirus; the etiologic agent of feline panleukopenia.
  • p.-like syndrome is characterized by decreased numbers of leukocytes, often an anemia and thrombocytopenia, resembling clinically infection by the feline panleukopenia virus. Occurs in cats infected by feline leukemia virus and in some cases may be due to coninfection with feline panleukopenia virus. Called also FeLV-associated enteritis.

• panlife cycle life history; the series of stages in physical that an organism passes through from the primary stage to the germinal stage of adult demise.

• panmyeloid [pan-mi′ -loid] pertaining to all elements of the bone marrow.

• panmyelophthisis [pan-mi″ -lof′thľ-sis] aplastic anemia.

• panmyelosis [pan-mi″ -lo′sis] proliferation of all the elements of the bone marrow.

• panniculitis inflammation of the subcutaneous fat. See also opportunistic mycobacterial infection.

  • lobular p. the inflammatory process primarily involves the fat lobules rather than the interlobular connective tissue.
  • lupus p. see lupus erythematosus.
  • necrotizing p. multifocal, erythematous, nonpruritic cutaneous lesions that ulcerate in the center and discharge seropurulent exudate; identifiable on histopathological examination.
  • nodular p. subcutaneous nodules that may become cystic or ulcerate or develop fistulous tracts that drain an oily material. They occur in dogs, cats, and horses, and may be sterile or caused by infectious agents.
  • postinjection p. occurs after a subcutaneous injection; the characteristics depend on the material injected, but range from a discrete nodule with a necrotic center or an area of hair loss with minimal inflammation.
  • pyogranulomatous p. see opportunist mycobacterial granuloma.
  • septal p. the inflammatory process primarily involves the interlobular connective tissue septae rather than the fat lobules.

• panniculus pl. panniculi [L.] a layer of membrane.

  • p. adiposus the subcutaneous fat; a layer of fat underlying the corium, well developed in pigs and marine mammals.
  • p. carnosus a muscular layer in the superficial fascia of most quadripedal mammals; it includes the cutaneous trunci.
  • p. muscle see panniculus carnosus (above).
  • p. reflex a bilateral twitch of the cutaneous trunci muscle along the back or flank in response to a stimulation in the thoracolumbar area. Absence of the reflex can help to localize the location of a lesion within the spinal cord between the T3 and L2 spinal cord segments

• pannier saddle bag

• pannus [pan′ s] 1. chronic superficial keratitis. 2. inflammatory granulation tissue, arising from synovial membrane, spreads as a membrane over articular cartilage; develops in association with chronic infectious fibrinous synovitis and some immune-mediated diseases, such as rheumatoid arthritis. 3. panniculus adiposus.

• panophthalmitis [pan″of-th l-mi′tis] inflammation of ocular structures and tissues from within all three of the tunics. Compare with endophthalmitis.

• panosteitis [pan″os-te-i′tis] 1. inflammation of every part of a bone. 2. a self-limiting disease of young, large-breed dogs, particularly German shepherd dogs, characterized clinically by shifting lameness and radiographically by enosteal and subperiosteal new bone formation on long bones. Called also enostosis, juvenile osteomyelitis, and eosinophilic panosteitis or panosteitis eosinophilica, because some cases are reported to have eosinophilia in peripheral blood.

• panostosis [pan″os-to′sis] see panosteitis.

• panotitis [pan″o-ti′tis] inflammation of all the parts or structures of the ear.

• pansinusitis [pan″si-n s-i′tis] inflammation involving all the paranasal sinuses.

  P-04.

  

  Synovitis and arthritis of hock joints of swine with pannus extending across the articular surface

  P-05.

  

  Radius and ulna of a 7-month-old male German shepherd dog with panosteitis. There is increased opacity within the medullary cavity of the ulna diaphysis and a portion of the radial diaphysis(red arrows). Compare this with the normal portion of the radius (yellow arrow)

• pansteatitis [pan″ste″ -ti′tis] 1. inflammation of body fat. 2. See yellow fat disease.

• pansystolic [pan″sis-tol′ik] the whole of systole; includes presystolic and systolic phases. See also heart murmur.

• panters atypical interstitial pneumonia of cattle.

• panthenol [pan′th -nol] nonproprietary name for pantothenyl alcohol; also called pantothenol; used as a moisturizer and to facilitate wound healing in topical products.

• Panthera genus in the family Felidae; includes jaguar (P. onca), leopard (P. pardus), lion (P. leo), tiger (P. tigris), and snow leopard (P. uncia).

• panting rapid, shallow breathing, a characteristic heat-losing reaction in dogs; represents an increase in dead-space ventilation resulting in heat loss without necessarily increasing oxygen uptake or carbon dioxide loss.

  • p. disease see atypical interstitial pneumonia, Zieria arborescens.

• pant(o)- word element. [Gr.] all, the whole.

• Panton–Valentine leukocidin a nonhemolytic toxin produced by Staphylococcus aureus that kills segmented neutrophils and macrophages.

• pantoprazole [pan-to′pr -zōl] a proton pump inhibitor used in the treatment of gastric ulceration and for preventing stress-related gastrointestinal ulceration in shock.

• pantothenic acid [pan″to-then′ik] a vitamin of the B complex group present in all living tissues as part of the coenzyme A (CoA) molecule or the acyl carrier protein.

  • p. a. nutritional deficiency a nutritional essential in all species other than ruminants which synthesize it in the rumen. Recorded as a natural occurrence only in poultry and pigs on heavy corn diets. Manifested in pigs by diarrhea, dermatitis, incoordination with a spastic gait and ulcerative colitis. Fowls show poor hatchability of eggs, poor feather development, and dermatitis. In fish, deficiency causes pathologic changes in the gills.

• pantothenyl alcohol alcohol of pantothenic acid (vitamin B5) that is oxidized in the body to pantothenate. Called also panthenol.

• pantropic [pan-tro′pik] having affinity for tissues derived from all three of the germ layers (ectoderm, endoderm, and mesoderm).

• Panulirus genus of spiny lobsters, members of the family Palinuridae; called also rock lobster, langouste.

• panuveitis [pan″u-ve-i′tis] inflammation of all parts of the uveal tract (iris, ciliary body, and choroid).

• panzootic [pan″zo-ot′ik] rarely used equivalent of pandemic when referring to animal diseases.

• papain [p -pān′] a proteolytic enzyme from the latex of pawpaw, Carica papaya, the active ingredient of meat tenderizers. In surgery it is used as a protein digestant and for enzymatic débridement and promotion of normal healing of surface lesions. Papain is also used in immunology to cleave immunoglobulin molecules into Fab and Fc fragments.

• Papaver [p -pav′ r] a plant genus of the family Papaveraceae that includes the poppies.

  • P. aculeatum may cause nitrate–nitrite poisoning.
  • P. nudicaule causes ataxia and muscle tremor. Called also Iceland poppy.
  • P. rhoeas a common weed in cultivation fields in Europe. Contains an isoquinoline alkaloid, e.g., rhoadine, and causes somnolence, abdominal pain, recumbency. Called also red poppy.
  • P. somniferum causes excitement and gastrointestinal disturbance. Called also opium poppy. See opium.

• papaveretum a mixture of all of the alkaloids of the opium poppy; it is better tolerated by dogs than morphine. Also known by its trade name Omnopon.

• papaverine [p -pav′ r-in] a synthetic alkaloid originally obtained from the opium poppy; the hydrochloride salt is used as a smooth muscle relaxant (antispasmodic).

• paper [pa′p r] see newsprint.

  • p. bark thorn Acaciasieberana.
  • p. bone disease see osteogenesis imperfecta, osteodystrophia fibrosa.
  • p. flowers see Psilostrophe.

• papilla [p -pil′] pl. papillae [L.] a small, nipple-shaped projection or elevation.

  • buccal p. see under dental, conical, lingual etc., papilla (below).
  • circumvallate p. vallate papilla.
  • conical p. one of the sparsely scattered fleshy elevations on the tongue or lining the cheeks of cattle.
  • p. of corium conical extensions of the fibers, capillary blood vessels, and sometimes nerves of the corium into corresponding spaces among downward- or inward-projecting rete ridges on the undersurface of the epidermis. Special papillae coriales occur on the sensitive corium of the frog of the horse’s hoof.
  • dental p., dentinal p. the small mass of condensed mesenchyme capped by each of the enamel organs in a developing tooth.
  • dermal p. finger- and ridge-like projections of the dermis that interdigitate with similar depressions in the epidermis.
  • duodenal p. either of the small elevations (major and minor) on the mucosa of the duodenum, the major at the entrance of the conjoined pancreatic and common bile ducts, the minor at the entrance of the accessory pancreatic duct.
  • filiform p. one of the short threadlike elevations covering most of the tongue surface. In cats and cattle, they are heavily cornified to give a rasping tongue.
  • foliate p. one of the parallel mucosal folds on the tongue margin at the junction of its body and root, best developed in the horse and pig but rudimentary or absent from other domestic animals.
  • fungiform p. one of the knob-like projections of the tongue scattered among the filiform papillae.
  • gingival p. the triangular pad of the gingiva filling the space between the proximal surfaces of two adjacent teeth.
  • hair p. the fibrovascular mesodermal papilla enclosed within the hair bulb.
  • ileal p. papilla carrying the terminal orifice of the ileum and its entrance to the large bowel.
  • incisive p. an elevation at the anterior end of the raphe of the palate onto which the incisive ducts open.
  • lacrimal p. see lacrimal punctum.
  • lenticular p. rounded horny elevations on the dorsum of the ruminant tongue that serve to compress regurgitated stomach contents against the palate during rumination, squeezing out liquid that is then swallowed while retaining solid material for further mastication.
  • lingual p. elevations on the surface of the tongue, containing the taste buds; the conical, filiform, foliate, fungiform, and vallate papillae.
  • major duodenal p. the papilla in the duodenum for the common opening of the bile duct and the pancreatic duct.
  • mammary p. the teat or nipple of the mammary gland.

    P-06.

    

    Incisive papilla in a dog

  • marginal tongue p. transient, fleshy, filiform papillae on the margin of the tongue of puppies, piglets, and kittens that are thought to facilitate sucking by helping the nursing animal form a vacuum in its mouth by sealing its tongue against the lips of the mouth.
  • optic p. optic disc.
  • palatine p. incisive papilla.
  • parotid p. the oral opening of the duct of the parotid salivary gland located opposite the third upper molar.
  • p. pili hair papilla.
  • renal p. the blunted apex of a renal pyramid.
  • ruminal p. papillae up to 0.5 in. long, flat or filiform that cover most of the ruminal wall but are absent from the pillars and the dorsal part of the dorsal sac.
  • tactile p. tactile corpuscles.
  • terminal hoof p. papillae on the distal ends of the sensitive laminae of the hoof.
  • tongue p. small projections from the mucous membrane of the tongue that include filiform, lenticular, fungiform, foliate, and vallate papillae; most are to assist in grooming, food prehension, and movement; some carry orifices for glands and others for taste.
  • p. unguiculiformes horny claw-shaped papillae at the reticulo-omasal orifice.
  • urethral p. a slight elevation in the vestibule of the vagina at the external orifice of the urethra.
  • vallate p. one of the eight to 12 large circular papillae arranged in a V near the base of the tongue.
  • p. of Vater, Vater’s p. major duodenal papilla.
  • wool p. as for hair papilla (above).

• papillary [pap′ľ-lar″e] pertaining to a papilla; having the characteristics of a papilla.

  • p. duct urine passes from the collecting tubules into the papillary ducts as the last section of the renal tubular system.
  • p. necrosis necrosis of the renal papilla.
  • p. squirting a feature of seborrheic dermatitis, zinc-responsive dermatoses; the superficial papillae are edematous and contain dilated vessels, the overlying epidermis is edematous and parakeratototic.
  • p. sulcus the groove around a vallate papilla on the tongue into which the ducts of gustatory glands discharge.

• papillectomy [pap″ľ-lek′t -me] excision of a papilla.

• papilledema [pap″il- -de′m] edema and sometimes hyperemia of the optic disc, without blindness or funduscopically detectable hemorrhage or inflammatory cell exudation from the optic disc (compare with optic neuritis); usually associated with increased intracranial pressure; called also ‘choked disc’.

• papillitis [pap″ľ-li′tis] inflammation of a papilla, especially of the optic disc. Called also optic neuritis.

• papilloadenocystoma [p -pil″o-ad″-no-sis-to′m] papillary cystadenoma.

• papillocarcinoma [p -pil″o-kahr″sľ-no′m] papillary carcinoma.

• papilloma [pap″ľ-lo′m ] the common wart. A benign tumor derived from epithelium, which may arise from skin, conjunctiva, mucous membranes, or glandular ducts. Varies from keratinized, to fibrovascular, squamous. Caused by a species-specific papillomavirus in young animals; may arise spontaneously in older animals. In cattle, also called angleberry. See also Papillomavirus, papillomatosis.

  P-07.

  

  Cat tongue with papillae

  • cutaneous p. commonly occur in older dogs, appearing as single or multiple, pedunculated or cauliflower-like masses on the head and paws; may be viral or nonviral. See also canine viral papillomatosis. Called also warts or verrucae.
  • fibrovascular p. single or multiple, small, benign, pedunculated fibrovascular skin tumors, that occur occasionally on the sternum, bony prominences, and trunk. Called also skin tag, keratin tag, soft fibroma, acrochordon.
  • inverted p. skin nodules covered by skin with a central pore; seen on abdomen and groin of young dogs.
  • plexus p. a rare tumor of the choroid plexus, often causing an internal hydrocephalus.

• papillomatosis [pap″ľ-lo-m -to′sis] disease state characterized by the development of multiple papillomas (‘warts’). See also papilloma, Papillomavirus, fibropapilloma.

  • canine viral p. multiple papillomas, caused by a papillomavirus, occur most commonly on the oral mucosa and lips of young dogs (canine oral papillomatosis). Occasionally skin, cornea, conjunctiva, and eyelids are also involved. The tumors may persist for several months, occasionally longer, but spontaneous regression is usual. See also cutaneous papilloma.
  • cottontail rabbit p. infection by a papilloma virus specific to Sylvilagus floridanus, causes cutaneous papillomas that may become malignant.
  • genital p. multiple fibropapillomas of the anogenital skin transmitted venereally in cattle, usually involving the vulva and penis. There is also a genital form of the disease in pigs. See bovine Papillomavirus and transmissible porcine papillomatosis (below).
  • internal p. see mucosal papillomatosis (below).
  • mucosal p. occur on mucosal surfaces of the oral cavity or cloaca and less often in the crop, esophagus, proventriculus, and ventriculus, primarily in psittacine birds; caused by psitacid herpvesvirus 1 (Pacheco’s disease virus); associated with bile duct and pancreatic duct carcinomas. Called also internal papillomatosis.
  • oral p. see oral lapine papillomatosis (below), canine viral papillomatosis (above).
  • oral lapine p. small, gray, sessile, or pedunculated tumors on the undersurface of the tongue and rarely at other sites in the mouth, caused by a papillomavirus. Seen in Oryctolagus and Sylvilagus spp.
  • teat p. there are five antigenically identified papillomaviruses that cause warts on the teats of cows. Lesions vary from ricegrain lesions to long tags of keratinized tissue.
  • transmissible porcine p. in the prepuce of the boar as papular 0.5- to 1-in.- diameter lesions; spontaneous disappearance and persistent subsequent immunity.

• Papillomaviridae a family of viruses that includes members that cause papilloma in various animal species. Major branches of the phylogenetic tree of papillomaviruses are considered genera, which are identified by Greek letters; minor branches are considered species. This taxonomic system does not affect the traditional identification and characterization of papillomavirus ‘types’, and of ‘subtypes’ and ‘variants’, which are taxa below the level of species. The family was formerly a subfamily in the Papovaviridae, which is now obsolete.

  P-08.

  

  Papilloma on a horse’s muzzle

  P-09.

  

  Skin tag (fibrovascular papilloma)

  P-10.

  

  Multiple viral papillomas on the lips of a young dog

• Papillomavirus [pap″ľ-lo′m -vi″r s] a virus in the family Papillomaviridae. They are nonenveloped, icosahedral viruses with a circular, supercoiled DNA genome of 8 kilobases and are specific to each animal species and in some cases to specific epithelial sites in that species. At present, 13 bovine, 15 canine, 7 equine, 8 feline, and 4 avian papillomaviruses are described. Virions are very stable and readily transmissible especially if there is abrasion such as by grooming with a curry comb. The type virus is the Shope papilloma virus of rabbits. See also sarcoid, papilloma, papillomatosis.

• papillomavirus [pap″ľ-lo′m -vi″r s] a member of the family Papillomaviridae. bovine p. (BPV) thirteen major types have been identified. BPV-1, BPV-2 and BPV-5 cause fibropapillomas of the skin of the anteroventral part of the body including the forehead, neck, and back, the common cutaneous wart, penile fibropapilloma, and frond and rice grain fibropapillomas on the udder and teat skin. BPV-2 is also associated with bladder cancer in cattle grazing bracken fern (Pteridium spp.). BPV-3 causes cutaneous papilloma; BPV-4 causes papilloma of the esophagus and small intestine, which can become malignant, particularly in animals fed bracken fern (Pteridium spp.); BPV-5 causes rice grain fibropapillomas on the udder, and BPV-6 causes frond epithelial papillomas of the bovine udder, and teats.

• Papillon [pah″pe-yaw′] a small, dainty dog with an alert expression, rounded head, and long, silky coat in white with colored patches. The large, rounded (‘butterfly’) ears are distinctive with their flowing fringe of hair and may be erect, resembling a butterfly, hence the name of the breed, or they may be dropped, a type called Phalene (moth), which is registered and shown as a separate breed in some countries. Called also butterfly dog.

• papilloretinitis [pap″ľ-lo-ret″ľ-ni′tis] inflammation of the retina and optic disc.

• papillotomy [pap″ľ-lot′ -me] incision of a papilla, as of a duodenal papilla.

  P-11.

  

  Fibropapillomas on a cow’s teat

• Papovaviridae [p -po″v -vir′ľ-de] an obsolete family name now replaced by Papillomaviridae and Polyomaviridae.

• papovavirus [p -po′v-vi″r s] a virus in the family Polyomaviridae.

• Pappenheimer body see Pappenheimer body.

• papple-shaped abdomen an abdomen pear-shaped on the right side and apple-shaped on the left.

• papular characterized by the development of epidermal or oral mucosal papules.

  • bovine p. stomatitis a benign stomatitis caused by a poxvirus in the genus Parapoxvirus related to the orf virus. Lesions occur in young cattle and are characterized by round papules that develop a roughened center that expands and may merge with other adjacent lesions to give a network effect. The lesions are on the buccal mucosa and the adjoining skin of the muzzle and occasionally esophagus and forestomachs. Occasionally manifest with lesions on the teat of milking cattle; also causes infections in humans with lesions characterized by large nodules on the hands and sometimes face.

• papulation [pap″u-la′sh n] the formation of papules.

• papule [pap′ūl] a small circumscribed, solid, elevated lesion of the skin.

  • follicular p. one arising from a hair follicle; hair projects from the center.
  • lichenoid p. one that is elevated and flat-topped.

• papulopustular [pap″u-lo-pus′tu-l r] marked by papules and pustules.

• papulosis [pap-u-lo′sis] the presence of multiple papules.

• papulosquamous [pap″u-lo-squa′m s] both papular and scaly.

• papulovesicular [pap″u-lo-v -sik′u-l r] marked by papules and vesicles.

• papyraceous [pap″ľ-ra′sh s] like paper.

  • p. fetal mummification the commonest form of fetal mummification; fluids are resorbed, the placenta being reduced to paper-like sheets.

• par [L.] pair.

• para [par′ ] 1. [L.] used with numerals to designate the number of pregnancies that have resulted in the birth of viable offspring, as para 0 (none—nullipara), para I (one—unipara), para II (two—bipara, secundipara), para III (three—tertiipara), para IV (four—quadripara). The number is not indicative of the number of offspring produced where multiple offspring occur with a pregnancy. 2. Stem used to indicate adjacency as in paraovarian cyst.

• para- [par′ ] 1. word element. [Gr.] beside, beyond, accessory to, apart from, against. 2. in chemistry, a prefix indicating the substitution in a derivative of the benzene ring of two atoms linked to opposite carbon atoms in the ring; abbreviated p-.

• para-aminobenzoic acid (PAB, PABA) [par″ --me″no-b n-zo′ik] a compound that is a growth factor for certain bacteria that use it to synthesize folic acid. Sulfonamides act by competing with it, thus inhibiting the action of dihydropteroate synthase, an enzyme in the folate synthesis pathway.

• para-aminohippuric acid (PAH, PAHA) [par″ - -me″no-hľ-pūr′ik] a derivative of para-aminobenzoic acid used to measure the effective renal plasma flow and to determine the functional capacity of the renal tubular excretory mechanism. Called also aminohippuric acid.

• para-aminophenol a substance used in the manufacture of dyes and drugs. May cause skin sensitization and methemoglobinemia.

  • p. derivative analgesics include acetanilid, acetophenetidin, and acetaminophen.

• para-aminophenylarsonic acid arsanilic acid. See also organic arsenic poisoning.

• para-aminosalicylic acid (PAS, PASA) see p-aminosalicylic acid.

• para-aortic [par″ -a-or′tik] beside the aorta.

  • p. bodies see para-aortic body.

• para-aural surrounding the ear.

  • p. abscess infection in the external ear canal or middle ear that extends to the surrounding soft tissues and forms a draining sinus through the skin because of obstruction of the external ear canal by atresia, neoplasm or proliferative tissue.

  P-12.

  

  Papular stomatitis. Large circular lesion on buccal mucosa with smaller lesions on the skin inside the upper lip

• para grass Brachiariamutica, Panicumpurpurascens.

• parabens see hydroxybenzoate.

• parabiosis [par″ -bi-o′sis] 1. the union of two individuals, as conjoined twins, or of experimental animals by surgical operation. 2. temporary suppression of conductivity and excitability.

• parablackleg bacillus see malignant edema.

• parabronchi [par″ -brong-ki′] tertiary bronchi in the avian lung. The domestic fowl has some 500 parabronchi each 1–2 mm diameter with the wall of each containing the complex respiratory epithelium.

• Parabronema a genus of spirurid nematodes found in large alimentary tract of wild animals. Includes P. africum, P. rhodesiense (in African elephants), P. rhinocerotis (rhinoceros, elephant).

• parabuxine one of the toxic alkaloids found in the plant Buxus sempervirens.

• paracasein [par″ -ka′sēn] casein. The insoluble product of rennin acting on caseinogen. In American terminology, the term for casein; not included in British nomenclature.

• paracentesis [par″ -sen-te′sis] surgical puncture of a cavity for the aspiration of fluid.

  • abdominal p. insertion of a trocar through a small incision or a needle into the abdominal cavity, to remove ascitic fluids, inject a therapeutic agent, or to collect a sample for cytological and chemical examination. It is an important technique in the examination of horses for colic and in investigation of causes of ascites in all species. Called also abdominocentesis.
  • anterior chamber p. aspiration of aqueous humor from the anterior chamber. Indicated as a diagnostic procedure in anterior uveitis and for intraocular masses. Called also aqueocentesis.

• pericardial p. see pericardiocentesis.

  • thoracic p. surgical puncture for drainage of the thoracic cavity and for collection of a sample of fluid for clinical pathology examination See also thoracentesis.
  • vitreous p. aspiration of vitreous to aid in the diagnosis of diseases of the posterior segment of the eye, e.g., intermediate uveitis, endophthalmitis, chorioretinitis, panophthalmitis, and intraocular neoplasia. See also hyalocentesis and vitreocentesis.

• paracephalus [par″ -sef′-l s] a fetus with a defective head and imperfect sense organs.

• paracervical [par″ -sur′vľ-k l] beside the neck, such as adjacent to the uterine cervix.

• paracetamol [par-as″ t-am′ol] an analgesic and antipyretic drug; see acetaminophen.

• parachordal [par″ -kor′d l] beside the notochord.

• paraclinical [par″ -klin′ľ-k l] pertaining to abnormalities (e.g., morphological or biochemical) underlying clinical manifestations (e.g., abdominal pain or fever). Used also as a collective term for the sciences that deal with pathology, including clinical pathology and immunology, and pathogenic agents including microbiology, parasitology, and toxicology.

  • p. tests laboratory tests in the area of pathology, clinical pathology, immunology, microbiology, parasitology, toxicology.

• Paracoccidioides [par″ -kok-sid″e-oi′dēz] a genus of dimorphic fungi in the phylum Ascomycota that proliferate by producing multiple budding yeast cells in the tissues.

  • P. brasiliensis the etiological agent of paracoccidioidomycosis. Previously called Blastomyces brasiliensis.

• paracoccidioidomycosis [par″ -kok-sid″e-oi″do-mi-ko′sis] an often fatal, chronic granulomatous disease of humans, dogs, cats, and most mammals caused by Paracoccidioides brasiliensis and P. lutzii. The disease is endemic in SouthAmerica, particularly Brazil. Infection primarily involves the lungs, but spreads to the skin, mucous membranes, lymph nodes, and internal organs. Called also South American blastomycosis.

• paracolitis [par″ -ko-li′tis] inflammation of the outer coat of the colon.

• Paracolobactrum not a valid genus. These bacteria rightly belong in Escherichia, Klebsiella, Salmonella, Edwardsiella spp. For P. arizonae, see Salmonella arizonae.

• paracolon bacteria [par″ -ko′l n] see Paracolobactrum.

• Paracooperia a genus of nematodes in the super-family Trichostrongyloidea. Found in ruminants in Africa.

  • P. nodulosa (P. matoffi) occurs in the intestines of buffalo and other wild animals and may cause nodules in the intestinal wall.

• Paracoroptes allenopitheci a mange mite species in the family Psoroptidae. Found in the ears and on the body of primates.

• paracortex [par″ -kor′teks] the thymus-dependent part of the lymph node.

• paracrine [par′ -krin] indicative of the action of the secretion of one kind of endocrine cell on another kind that is not the normal effector cell.

  • p. hormones in contrast to true endocrines these hormones are not released into the bloodstream but into the surrounding tissues and act in the immediate vicinity, e.g., intestinal mucosal hormones.

• paracystic [par″ -sis′tik] situated near the urinary bladder.

• paracystitis [par″ -sis-ti′tis] inflammation of tissues around the bladder.

• paradidymis [par″ -did′ľ-mis] remnants of mesonephric tubules sometimes found as a small body near the head of the epididymis.

• paradigm [par″ -dim] a pattern of thought, a similarity of conceptualization.

• paradistemper [par″ -dis-tem′p r] an old term for clinical syndromes that are now known to be manifestations of canine distemper, e.g., hardpad disease, or that have been shown to be separate diseases, e.g., infectious canine hepatitis.

• paradoxical [par″ -dok′sľ-k l] different from what is expected; at variance with the established laws.

  • p. motion see paradoxical respiration (below).
  • p. respiration a type of breathing in which all or part of a lung inflates during inspiration and balloons out during expiration; the opposite of normal chest motion. Called also paradoxical motion. The condition seriously inhibits the movement of gases during respiration and can produce severe and even fatal cardiovascular disturbances and respiratory insufficiency if not quickly relieved by emergency treatment. Paradoxical respiration or paradoxical motion of the lung usually results from traumatic injury to the thorax (flail chest) in which several ribs are fractured in two or more places and are no longer attached by bony cartilage to the rest of the rib cage. The condition can also be seen following surgical removal of several ribs and in paralysis of the diaphragm.
  • p. septal motion in echocardiography, the interventricular septum moves away from the left ventricular free wall during systole. Normally, it would move toward the wall. It is seen in right ventricular hypertrophy.

• Paraelaphostrongylus an incorrect spelling of Parelaphostrongylus.

• paraesophageal [par″ -e-sof″-je′ l] beside the esophagus.

  • p. herniation see paraesophageal hernia.

• Parafasciolopsis a genus of flukes (digenetic trematodes) in the family Fasciolidae.

  • P. fasciolaemorpha found in the digestive tract and gallbladder of the elk and deer.

• paraffin [par′ -fin] 1. kerosene. 2. petrolatum. 3.a purified hydrocarbonwax used for embedding histological specimens.

  • p. embedding technique the most commonly used technique for the preparation of slides of tissue for light microscopic examination.
  • liquid p. liquid petrolatum. See mineral oil.

• paraffinoma [par″ -fin-o′m] a chronic granuloma produced by foreign body reaction to injected mineral oils or silicone.

• Parafilaria [par″ -fľ-lar′e-] a genus of nematodes in the filarioid family Filariidae.

  • P. antipini found in deer.
  • P. bovicola causes hemorrhagic nodules in the skin of cattle and buffalo.
  • P. multipapillosa (syn. Filaria haemorrhagica) causes nodules in the subcutaneous and intermuscular tissues of horses. The nodules break open and discharge blood and then heal. They reappear each summer.

• parafilariasis [par″ -fil″-ri′ -sis] see Parafilaria multipapillosa.

• Parafilaroides a genus of nematodes in the metastrongyloid family Filaroididae; cause lesions in the lungs of aquatic mammals. Includes P. decorus (sealions), P. gymnurus (harbor seals), P. nanus and P. prolificus (Stellar’s sea lion).

• parafollicular [par″ -f-lik′u-l r] close to a follicle.

  • p. cell a C cell of the thyroid gland.

• paraformaldehyde [par″ -for-mal′d -hīd] a polymer of formaldehyde with many of the same properties. It is used in preparing tissue fixatives for special tissue preparations, particularly electron microscopy. Called also polyoxymethylene.

• paraganglioma [par″ -gang″gle-o′m] a tumor of the tissue composing the paraganglia.

• paraganglion [par″ -gang′gle-on] pl. paraganglia [Gr.] a collection of chromaffin cells derived from neural ectoderm, occurring outside the adrenal medulla, usually near the sympathetic ganglia and in relation to the aorta and its branches. Most secrete epinephrine (adrenaline) or norepinephrine (noradrenaline).

• Paragle redicum an anthomyiid fly that lays its eggs in canine feces.

• paraglossia [par″ -hi″po-glos′e-] inflammation of the oral tissues under the tongue.

• paragonimiasis [par″ -gon″ľ-mi′ -sis] infection with lung flukes of the genus Paragonimus. Characterized by lethargy, cough, dyspnea. On autopsy there is an eosinophilic peritonitis, pleurisy and myositis, and a chronic bronchitis and granulomatous pneumonia.

• Paragonimus [par″ -gon′ľ-m s] a genus of digenetic trematode parasites in the family Paragonimidae. Causes paragonimiasis.

  • P. africanus, P. caliensis, P. iloktsuenensis, P. mexicanus, P. ohirai, P. peruvianus, P. uterobilateralis found in the lungs of a large number of animal species.
  • P. kellicotti found in the lungs of cat, dog, and pig. Mink and muskrat are the probable primary hosts.
  • P. westermani found in the lungs and other organs of most animal species, and humans.

• paraherquamide an anthelmintic effective against nematode parasites in ruminants, but not in use due to low safety margin. See also derquantel.

• Parahistomonas a genus of protozoa in the family Monocercomadidae.

  • P. wenrichi some similarity to Histomonas spp. but is nonpathogenic in gallinaceous birds, especially pheasants.

• parahormone [par″ -hor′mōn] a substance, not a true hormone, that has a hormone-like action in controlling the functioning of some distant organ.

• Parainfluenzavirus (PI virus) one of the three genera of viruses in the family Paramyxoviridae.

  • p. 1 causes mild to severe respiratory disease in young mice. Also called Sendai virus. Occurs also in humans, rats, guinea pigs, rabbits, pigs, and nonhuman primates.
  • p. 2 a group of viruses, closely related to canine parainfluenza virus 5 and simian virus 5. This virus affects primarily humans.
  • p. 3 involved in the complex etiology of shipping fever in cattle and similar respiratory tract infections in sheep, goats, and possibly horses.
  • p. 4 respiratory disease in humans.
  • p. 5 1. 2. this group causes inapparent respiratory infections to mildsevere respiratory disease in dogs. Associated with kennel cough in high density, close contact dogs. Usually polymicrobial with other viruses and bacteria.

• parakeelia, parakeelya see Calandrinia.

• parakeets one of the bird groups known as typical parrots in the family Psittacidae. Small parrots with long tails and includes the budgerigar.

• parakeratosis [par″ -ker″ -to′sis] persistence of the nuclei of keratinocytes as they rise into the horny layer of the skin; it occurs normally in the cornifying stratified squamous epithelium of the mouth, esophagus, and vagina. When it occurs on the keratinizing external skin it indicates disordered keratinization. Affected skin is scaly and thickened to some degree. Occurs as a specific disease in pigs fed on rations deficient in zinc; the effect is exacerbated on diets high in calcium.

  • inherited p. an autosomal recessive disorder, occurs in calves, which are normal at birth but develop parakeratosis all over the body, especially on the legs and die after a long illness. Responds to treatment with zinc given orally. See also thymic hypoplasia. Called also lethal trait A46, adema disease.
  • nasal p. a rare genodermatosis of Labrador retrievers inherited as an autosomal recessive trait; from a young age, the nasal planum becomes dry, thickened, and develops proliferative changes with crusts and fissures. There may be focal depigmentation. Hyperkeratosis may also occur on the footpads. A DNA test is available.
  • ruminal p. the ruminal papillae are enlarged, leathery, and adhered in clumps. The lesion is most severe in the dorsal part of the sac. Occurs principally in animals fed pelleted feed.

• parakeratotic pertaining to parakeratosis.

  • p. caps foci of parakeratotic hyperkeratosis.

• parakinesia [par″ -kľ-ne′zh] perversion of motor powers causing strange and unnatural movements; in ophthalmology, irregular action of an individual ocular muscle.

• paralagenidiosis a cutaneous oomycete infection of dogs in the southeastern US caused by Paralagenidium karlingii; similar in clinical appearance to cutaneous pythiosis; solitary or multiple nodules, thickenings or ulcers in the skin are slowly progressive over years and rarely extend deeper than the subcutis.

• paraldehyde [par-al′d -hīd] a sedative and hypnotic that has an unpleasant taste and imparts an unpleasant odor to the breath. Because of its low therapeutic index, it is now little used.

• parallagma [par″ -lag′m] displacement of a bone or of the fragments of broken bone.

• parallergy [par-al′ r-je] a condition in which an allergic state, produced by sensitization to a specific allergen, predisposes the body to react to other allergens with clinical manifestations that differ from the original reaction.

• paralumbar [par″ -lum′b r] next to the lumbar area.

  • p. fossa see paralumbar fossa.

• paralysis [p -ral′ľ-sis] loss or impairment of motor function in a part due to a lesion of the neural or muscular mechanism; also, by analogy, impairment of sensory function (sensory paralysis). Called also palsy. Motor paralysis may be expressed as flaccid, with loss of motor tone in the case of a lower motor neuron lesion, or spastic, in the case of an upper motor neuron lesion. See also paraplegia, quadriplegia, hemiplegia, and paralyses of individual cranial and peripheral nerves.

  • p. of accommodation paralysis of the ciliary body muscles; used to reduce accommodation and pain due to ciliary body spasm.
  • anal p. manifested by flaccidity and lack of tone of the anal sphincter, and loss of house training restraint in companion animals.
  • antepartum p. pressure on sciatic nerves by a large fetus in late pregnancy in a cow can cause posterior paralysis that is cured by a cesarean section.
  • ascending p. spinal paralysis that progresses forward involving first the hindlimbs then the forelimbs, then the intercostal muscles, then the diaphragm, and finally the muscles of the neck.
  • birth p. that due to injury received by the neonate at birth.
  • bladder p. manifested by fullness of the bladder and response to manual pressure. See also motor paralytic urinary bladder.
  • cage p. see thiamine nutritional deficiency.
  • central p. any paralysis due to a lesion of the brain or spinal cord.
  • cerebral p. paralysis caused by some intracranial lesion.
  • Chastek p. see thiamine nutritional deficiency.
  • compression p. that caused by pressure on a nerve.
  • congenital p. paralysis of the newborn. Many cases are due to birth trauma especially when lay persons exert excessive traction. Other causes are enzootic ataxia, inherited congenital paraplegias in calves and pigs, spina bifida and spinal dysraphism, and occipito-alanto-axial malformations in foals and puppies.
  • conjugate p. loss of ability to perform some parallel ocular movements.
  • coonhound p. see polyradiculoneuritis.
  • crossed p. paralysis affecting one side of the head and the other side of the body.
  • curled toe p. a disease of poultry caused by a nutritional deficiency of riboflavin. See also curled toe paralysis.
  • decubitus p. paralysis due to pressure on a nerve from lying for a long time in one position.
  • esophageal p. manifested by inability to swallow, and regurgitation.
  • facial p. weakening or paralysis of the facial nerve. See also facial paralysis.
  • flaccid p. paralysis characterized by loss of voluntary movement, decreased tone of limb muscles, absence of tendon reflexes and neurogenic atrophy.
  • immunological p. the absence of immune response to a specific antigen. See also tolerance.
  • infectious bulbar p. see Aujeszky’s disease.
  • inherited posterior p. congenital paraplegia recorded in cattle and pigs. There are other nervous signs, e.g., opisthotonos, in some forms.
  • ischemic p. local paralysis due to stoppage of circulation.
  • lambing p. maternal obstetric paralysis in the ewe.
  • laryngeal p. see laryngeal hemiplegia.
  • mixed p. combined motor and sensory paralysis.
  • motor p. paralysis of the voluntary muscles.
  • nerve p. paralysis caused by damage to the local motor nerve supply. See also peripheral nerve paralysis (below).
  • obstetric p. a common abnormality after a difficult calving, especially in a heifer. It is caused by pressure on peripheral nerves, and manifests itself as weakness, paresthesia in one hindleg, or difficulty or inability to rise. The ligaments, joints, and muscles are normal. See also obturator paralysis.
  • partial p. see paresis.
  • peripheral nerve p. the part deprived of its peripheral nerve supply shows flaccid paralysis, absence of spinal reflexes, muscle atrophy, and a subnormal temperature.
  • postcalving p. see maternal obstetric paralysis.
  • posterior p. paralysis of the hindlimbs, tail, and perineum. See also paraplegia.
  • progressive posterior p. see progressive ataxia.
  • range p. see Marek’s disease.
  • sensory p. loss of sensation resulting from a morbid process.
  • spastic p. paralysis with rigidity of the muscles and heightened deep muscle reflexes.
  • tongue p. see hypoglossal nerve paralysis.
  • transient p. syndrome a syndrome in birds affected with Marek’s disease. Ataxia and paralysis last for several days followed by recovery and subsequently, after a lapse of several months, a fatal outcome from MD.

• paralytic [par″ -lit′ik] 1. pertaining to paralysis. 2. an animal affected with paralysis.

  • p. bladder see atonic neurogenic urinary bladder.
  • p. rabies see rabies.
  • p. shellfish poisoning see shellfish.

• paralyzant [par′ -līz″ nt] 1. causing paralysis. 2. an agent that causes paralysis.

• paramastitis [par′ -mas-ti′tis] inflammation of tissues around the mammary gland.

• parameatal [par″ -me-a′t l] situated near or around a meatus.

• Paramecium [par″ -me′se- m] a genus of ciliate protozoa, known also as Lady Slippers due to their appearance. These organisms are widespread in freshwater, marine, and brackish water; often found in stagnant ponds.

• paramedian [par″ -me′de- n] beside the midplane.

• paramesonephric see müllerian duct.

  • p. duct inhibiting factor secreted by the sustentacular (Sertoli) cells of the fetal, but not adult, testis; promotes the degeneration of the paramesonephric ducts. Also secreted by granulosa cells of growing follicles in adult female. Useful in diagnosis of cryptorchidism in males and granulosa cell tumors in females. Used for distinguishing intact from spayed dogs and cats. Called also anti-müllerian hormone.

• parameter [p -ram′-t r] 1. in mathematics and statistics, an arbitrary constant, such as a population mean or standard deviation. It wholly or partly determines a probability distribution. 2. a property of a system that can be measured numerically.

• paramethadione an anticonvulsant drug.

• paramethasone [par″ -meth′ -sōn] a glucocorticoid used as the 21- acetate ester for its anti-inflammatory and antiallergic effects.

• Parametorchis [par″ -m -tor′kis] a genus of digenetic trematodes in the family Opisthorchidae.

  • P. complexus found in the bile ducts of dogs and cats. Can cause abdominal pain, ascites, jaundice.

• parametric [par″ -me′trik] 1. situated near the uterus; parametrial. 2. pertaining to or defined in terms of a parameter.

  • p. method a method of testing a hypothesis that requires the user to assume a particular model for the distribution of data, e.g., Poisson, normal.

• parametritis [par″ -m -tri′tis] inflammation of the parametrium.

• parametrium [par″ -me′tre- m] the extension of the subserous coat of the uterus laterally between the layers of the broad ligament.

• Paramoeba [par″ -me′b] genus of a parasite associated with amoebic gill disease in salmonids.

• Paramonostomum [par″ -mo-nos′to-m m] intestinal flukes (digenetic trematodes) of the family Notocotylidae; P. alveatum and P. parvum are found in ducks but appear to cause little injury.

• paramphistomes [p -ram′fľ-stōm] digenetic trematodes, members of the family Paramphistomatidae; belonging to genera such as Paramphistomum, Calicophoron, Cotylophoron, Gigantocotyle.

• paramphistomiasis [par″am-fis-to-mi′ -sis] infestation with members of the family Paramphistomatidae.

• paramphistomosis [par″am-fis-to-mo′sis] the disease caused by infestation of ruminants with stomach flukes. Adult flukes cause weight loss, loss of production, and anemia. Immature flukes cause diarrhea also. Called also stomach fluke disease. See also Paramphistomum, Calicophoron, Ceylonocotyle and Cotylophoron.

• Paramphistomum [par″am-fis′to-m m] a genus of ruminal flukes (digenetic trematodes) in the family Paramphistomatidae.

  • P. cervi, P. ichikawai, P. microbothrium important parasites of cattle, sheep, goats, and buffalo.
  • P. explanatum, P. gotoi, P. hiberniae, P. liorchis, P. microbothrioides, P. scotiae are other paramphistomes of cattle.

• paramyoclonus [par″ -mi-ok′l-n s] a condition characterized by myoclonic contractions of various muscles.

  • p. multiplex a condition characterized by sudden shocklike contractions.

• paramyotonia [par″ -mi″o-to′ne-] a disease marked by tonic spasms due to disorder of muscular tonicity, especially a hereditary and congenital affliction.

  • p. congenita myotonia congenita.

• paramyotonic syndromes [par″ -mi″o-to′nik] signs include stiffness and reluctance to walk, exacerbated by cold and by exercise; include congenital paramyotonia in King Charles spaniels, hyperkalemic periodic paralysis in horses, feline hypokalemic polymyopathy.

• Paramyxoviridae [par″ -mik″so-vir′ľ-de] a family of viruses in the order Mononegavirales containing two subfamilies, Paramyxovirinae and Pneumovirinae. Viruses in the family are large (180 nm diameter), enveloped, and contain a genome that is a single molecule of single-stranded negative sense RNA. Paramyxovirinae comprises five genera: (1).Avulavirus (type species Newcastle disease virus): (2) Henipavirus (type species Hendra virus; includes Nipah virus): (3) Morbillivirus (type species measles virus; others include rinderpest virus, canine distemper virus, phocine distemper virus, cetacean morbillivirus (dolphins and porpoises), peste des petitis ruminants virus): (4) Respirovirus (type species Sendai virus; others include human parainfluenza viruses 1 and 3): (5) Rubulavirus (type species mumps virus; others include human parainfluenza viruses 2 and 4, canine parainfluenza 5, simian virus 5, Menangle virus, Tioman virus, and an unnamed genus that contains Tupia paramyxovirus). Pneumovirinae which contains two genera: (1): Pneumonovirus (type species human respiratory syncytial virus; others include bovine respiratory syncytial virus) and (2) Metapneumovirus (type species avian pneumovirus; also human metapneumonavirus). there are several other viruses that are unassigned.

• paramyxovirus [par″ -mik′so-vi″r s] a member of the order Mononegavirales subfamily Paramyxovirinae.

  • avian p’s include avian paramyxovirus-1 (Newcastle disease virus); avian paramyxovirus-2, which causes Yucaipa disease; avian paramyxovirus-3, which causes depression, coughing, and a drop in egg production in turkeys and occasionally chickens and psittacine birds; and avian paramyxovirus-6, which causes mild respiratory infection in turkeys.
  • p. encephalomyelitis see blue eye disease.

• paranal sacs [par″an-al] see anal sacs.

• Paranaplasma an obsolete name for some members of the genus Anaplasma. P. caudata is now classified as A. caudatum.

• paranasal [par″ -na′z l] beside the nasal cavity.

  • p. sinuses mucosa-lined air cavities in the bones of the skull, communicating with the nasal cavity. See also sinus.
  • p. sinus cysts occur in horses primarily in the caudal maxillary sinus and occasionally in the frontal or rostral sinus. Very young or old horses are affected. They present with nasal respiratory obstruction, facial swelling, and nasal discharge. An increase in intramaxillary sinus pressure results in displacement of the nasal septum in a significant proportion of cases.
  • p. sinus polyps rare cause of nasal bleeding in horses.

• paraneoplastic [par″ -ne″o-plas′tik] auxiliary to neoplasia.

  • p. syndrome a collective term for disorders arising from metabolic effects of cancer on tissues remote from the tumor; such disorders may, for example, appear as primary endocrine, hematological, or neuromuscular disorders. See also pseudohyperparathyroidism.

• paranephric [par″ -nef′rik] 1. near the kidney. 2. pertaining to the adrenal gland.

• paranephritis [par″ -n -fri′tis] 1. inflammation of the adrenal gland. 2. inflammation of the connective tissue around the kidney.

• paranephros [par″ -n ′fros] pl. paranephroi [Gr.] an adrenal gland.

• paraneural [par″ -noor′ l] alongside a nerve.

• Paranoplocephala a genus of tapeworms in the family Anoplocephalidae. Parasitic in rodents. See also Anoplocephaloides.

  • P. mamillana see Equinia.

• paranucleus [par″ -noo′kle- s] a body (e.g., small mass of chromatin) that can be seen in the cell protoplasm adjacent to the nucleus.

• paraovarian [par″ -o-var′e- n] beside the ovary.

  P-13.

  

  Paranasal sinuses of the dog

  P-14.

  

  Paraphimosis with edema of prepuce and necrosis of the exposed tip of the penis

  • p. cyst vestige of embryological tissue in ligaments (especially mesosalpinx) and uterine tube close to the ovary. Includes epoophoron, paroophoron, fimbrial cyst; usually not detrimental to fertility. Large cysts may undergo torsion and cause pain.

• paraparesis [par″ -p -re′sis] weakness or partial paralysis of the hindlimbs. Commonly used to denote an unsteady or ataxic hindlimb gait.

• paraphimosis [par″ -fi-mo′sis] inability to retract the extended penis back into the preputial cavity because of its swollen state, or because of constriction of the preputial orifice.

• paraplectic [par″ -plek′tik] paraplegic.

• paraplegia [par″ -ple′j] paralysis of the hindlimb and, in some cases, the posterior part of the body caudal to the last cervical vertebrae. The paralysis may be acute in onset as in fracture of a lumbar vertebra, or gradual; it may be spastic or flaccid. Paraplegia is a form of central nervous system paralysis, in which the paralysis affects all the muscles of the parts involved. In the majority of cases, paraplegia results from disease or injury of the spinal cord that causes interference with nerve paths connecting the brain and the muscles.

  • p. cart a two-wheeled cart into which a paraplegic dog can be strapped so that its hindquarters are supported and its front limbs rest normally on the ground to provide a motor system. Used for short periods to give the animal exercise. A wheelchair for dogs.
  • inherited congenital p. is observed in cattle and pigs. The paralysis may be flaccid or spastic, and there may or may not be degenerative lesions in the spinal cord.

• paraplegiform [par″ -ple′jľ-form] resembling paraplegia.

• Parapoxvirus [par″ -poks′vi-r s] a genus in the order Poxvirales, family Poxviridae; includes viruses that cause bovine papular stomatitis, contagious ecthyma (scabby mouth) of sheep.

• paraprofessional [par″ -pro-fesh′n- l] 1. a person who is specially trained in a particular field or occupation to assist a veterinarian. 2. allied animal health professional; see veterinary assistant, nurse, animal health technician, technologist.

• paraprostatic [par″ -pros-tat′ik] beside the prostate.

  • p. cyst arise from mesonephric duct remnants, outside the prostatic parenchyma. In dogs, they can be sizeable before producing clinical signs related to compression of the colon or urethra.

• paraprotein [par″ -pro′tēn] immunoglobulin produced by a clone of neoplastic plasma cells proliferating abnormally, e.g., myeloma proteins and cryoglobulins. See also monoclonal gammopathy.

• paraproteinemia [par″ -pro″tēn-e′me-] the presence in the blood of paraproteins.

• paraproteinuria [par″ -pro″te-nu′re-] the presence in the urine of paraproteins.

• parapsoriasis [par″ -s-ri′ -sis] a disease resembling psoriasis of humans. There are erythematous, scaly plaques on the body, with hair loss and secondary bacterial infection.

• paraquat [par′ -kwaht] a dipyridilium herbicide that initially causes stomatitis, colic, vomiting, and diarrhea, then 2–10 days later causes pulmonary edema and hemorrhage, which leads to a fibrosing pneumonitis and death in all species if given in sufficiently large doses. Renal damage can also occur. Its use is banned in most countries.

• parareflexia [par″ -re-flek′se-] any disorder of the reflexes.

• pararosaniline [par″ -ro-zan′ľ-lin] a basic dye; a triphenylmethane derivative, one of the components of basic fuchsin.

• pararrhythmia [par″ -rith′me-] parasystole. Persistence of normal pacemaker activity complicated by the emergence of extrasystoles such that two pacemakers are firing independently of one another.

• parasacral [par″ -sa′kr l] situated near the sacrum.

• Parascaris [p r-as′k r-is] a genus of roundworms in the family Ascarididae.

  • P. equorum (syn. Ascaris equorum) found in the small intestine of horses and zebras. In foals up to 9 months of age, heavy infestation with migrating larvae causes coughing. Heavy burdens of adult worms may cause diarrhea, debility, potbelly in young animals.
  • P. univalens A species very similar to P. equorum, the two occurring in mixed infections. Differentiable from P. equorum genetically, but morphologically only by the shape of the spicule tip.

• parasinoidal [par″ -si-noi′d l] situated along the course of a sinus.

• parasite [par′ -sīt] a plant or animal that lives upon or within another living organism at whose expense it obtains some advantage. See also symbiosis. Among the many parasites in nature, some feed upon animal hosts, causing diseases ranging from the mildly annoying to the severe and often fatal. Parasites include multicelled and single-celled animals, fungi, and bacteria. Viruses are sometimes considered to be parasites. However, the commonest use of the word refers to the multicellular helminth, arachnid, crustacean (copepod), and arthropod parasites.

  • accidental p. one that parasitizes an organism other than the usual host.
  • e. parasites ectoparasites.
  • facultative p. one that may be parasitic upon another organism but can exist independently.
  • incidental p. accidental parasite.
  • obligate p., obligatory p. one that is entirely dependent upon a host for its survival.
  • periodic p. one that parasitizes a host for short periods.
  • temporary p. one that lives free of its host during part of its life cycle.

• parasitemia [par″ -si-te′me-] the presence of parasites, including filariae and protozoa, in the blood.

• parasitic [par″ -sit′ik] pertaining to parasites. See also arteritis, bronchitis, gastritis, gastroenteritis, hypersensitivity, pneumonia, tracheobronchitis, helmintic.

• parasiticide [par″ -sit′ľ-sīd] destructive to parasites; also, an agent that is destructive to parasites.

• parasitism [par″ -si′tiz- m] 1. symbiosis in which one population (or individual) adversely affects another, but cannot live without it. 2. infection or infestation with internal or external parasites.

• parasitize [par′ah-sľ-tīz″] to live on or within a host as a parasite.

• parasitogenic [par″ah-sľ-to-jen′ik] due to parasites.

• parasitological [par″ah-sľ-to-loj′ľ-k l] pertaining to or emanating from parasitology.

  • p. examination includes examination of feces for protozoa, worm eggs, or larvae and for tapeworm segments, skin scrapings for arthropod para-sites, blood samples for protozoa, microfilariae, for plasma pepsinogen concentrations, and examination of gross specimens.

• parasitologist [par″ -si-tol′ -jist] a specialist in the study of parasites.

• parasitology [par″ -si-tol′ -je] the scientific study of parasites and parasitism.

• parasitosis [par″ -si-to′sis] a disease caused by a parasitic infestation. See also helminthiasis.

  • delusional p. a mental disorder of humans in which they (incorrectly) believe they are infested with parasites, most commonly on or under the skin; affected persons often attribute the source of parasites to their pet and seek veterinary assistance in treating them. Their demands can be unreasonable and relentless.

• parasitotropic [par″ -si″to-tro′pik] having an affinity for parasites.

• paraspadias [par″ -spa′de- s] a congenital condition in which the urethra opens on one side of the penis.

• Paraspidodera a genus of nematodes in the superfamily Heterakoidea.

  • P. uncinata occurs in the large intestine of guinea pigs and agouti and appears to be nonpathogenic.

• parasternal [par″ -ster′n l] beside the sternum.

• Parastrigea intestinal digenetic trematodes in the family Strigeidae.

  • P. robusta found in the intestine of domestic ducks and may cause anemia and hemorrhagic enteritis.

• parasympathetic [par″ -sim″p -thet′ik] pertaining to the parasympathetic nervous system.

  • p. cholinergic vasodilator fibers cause dilatation of blood vessels in tissues including cerebral vessels, tongue, salivary glands, external genitalia, bladder, rectum.
  • p. nervous system part of the autonomic nervous system, the preganglionic fibers of which leave the central nervous system with cranial nerves III, VII, IX, and X, and several sacral nerves (depending on species); postganglionic fibers are distributed to the heart, smooth muscles, and glands of the head and neck, and thoracic, abdominal, and pelvic viscera. Almost three-quarters of all parasympathetic nerve fibers are in the vagus nerves, which serve both the thoracic and abdominal regions of the body. The predominant secretion of the nerve endings of the parasympathetic nervous system is acetylcholine, which acts on the various organs of the body to either excite or inhibit certain activities. For example, stimulation of the parasympathetic system causes constriction of the pupil of the eye and contraction of the ciliary muscle; increase of the glandular secretion of enzymes, as in the case of the pancreas; increased peristalsis; and a slowed heart rate. Excitation of the sympathetic nervous system often results in an effect opposite to that of the parasympathetic system; however, most organs are predominantly under the control of either one or the other of the two nervous systems that compose the autonomic nervous system.
  • p. outflow the total of parasympathetic nerves that leave the central nervous system. Includes the cranial and sacral outflows.

• parasympatholytic [par″ -sim″p -tho-lit′ik] an agent that inhibits or induces effects opposite to those of the parasympathetic nervous system; see anticholinergic.

• parasympathomimetic [par″ -sim″p -tho-mľ-met′ik] an agent that stimulates or induces effects resembling those of the parasympathetic nervous system; also called a cholinergic agent.

• parasynapsis [par″ -sľ-nap′sis] the union of chromosomes side-by-side during meiosis.

• parasynovitis [par″ -sin″o-vi′tis] inflammation of the tissues about a synovial sac.

• parasystole [par″ -sis′t -le] a cardiac irregularity attributed to the interaction of two foci independently initiating cardiac impulses at different rates. Called also pararrhythmia.

• paratenic [par″ -ten′ik] see paratenic host.

• paratenon [par″ -ten′on] loose connective tissue filling the interstices of the fascial compartment in which a tendon is situated and that allows it to move freely. Is not organized into discrete tendon sheaths, although not as freely as within a true synovial tendon sheath.

• parathion, [par″ -thi′on] see organophosphorus compound.

• parathormone [par″ -thor′mōn] parathyroid hormone.

• parathyroid [par″ -thi′roid] 1. situated beside the thyroid gland. 2. one of the parathyroid glands. 3. a preparation containing parathyroid hormone from animal parathyroid glands; used for diagnosis and treatment of hypoparathyroidism.

  • p. calcium-regulating hormone see parathyroid hormone (below).
  • p. cyst remnants of the embryonic duct that connects the parathyroid and the thymus during embryogenesis. Called also Kursteiner’s cyst.
  • p. gland small body in the region of the thyroid gland, occurring in a variable number of pairs, commonly two. The parathyroid contains two types of cell: chief cells and oxyphils. Chief cells are the major source of parathyroid hormone (PTH), the secretion of which is dependent on the serum calcium concentration. Through a closed-loop feedback mechanism a low serum calcium concentration stimulates secretion of PTH; conversely, a high serum calcium concentration inhibits its secretion. The essential role of PTH is maintenance of a normal serum calcium concentration in association with vitamin D and calcitonin.
  • p. gland hyperplasia may be focal and nodular or, more importantly diffuse. The latter occurs in cases suffering long-standing nutritional deficiency of calcium or renal insufficiency.
  • p. hormone (PTH) a simple, straight-chain polypeptide, synthesized in chief cells and stored in secretory granules. The hormone stimulates the formation and activity of resorptive osteocytes so that calcium is released into body fluids without extensive bone remodeling. This is its mineral homeostatic function and is a relatively quick, short duration response. It is also concerned in skeletal homeostasis by stimulating osteoclastic osteolysis, the slower-acting process of bone remodeling.
  • p. hormone-related protein (PTH-rP), p. hormone-like peptide associated with humoral hypercalcemia of malignancy (HHM); see pseudohyperparathyroidism.
  • p. hyperfunction see hyperparathyroidism, osteodystrophia fibrosa.
  • p. secretory protein stored in secretory granules with parathyroid hormone but has no known function. Called also chromogranin A.
  • p. tumors carcinomas occur rarely and adenomas more commonly, particularly in older dogs. Either type of tumor may be nonfunctional or, if functional, cause a primary hyperparathyroidism.

• parathyroidectomy [par″ -thi″roid-ek′t -me] excision of a parathyroid gland. Complete removal of all parathyroid tissue results in severe hypocalcemia.

• parathyroiditis [par″ -thi″roid-i′tis] usually a diffuse lymphocytic lesion, probably immune-mediated, and terminating in loss of most of the chief cells and replacement with fibrous tissue. Hypocalcemia may result.

  • lymphocytic p. a common finding in idiopathic hypoparathyroidism in dogs; the gland tissue may be almost completely replaced by lymphocytes. It may be an autoimmune disease.

• parathyrotropic [par″ -thi″ro-tro′fik] having an affinity for the parathyroid glands.

• paratope [par′ -tōp] the site in the variable region of an antibody or T cell receptor that binds to an antigenic epitope. Called also antigen-binding site.

• paratrichial [par′ -trik′ľ- l] literally beside the hair or hair follicle; used to refer to the apocrine sweat glands.

  • p. cystic dilation cystic dilation of the apocrine sweat gland occurs with or without hyperplasia of the glandular tissue.
  • p. sweat gland see sweat glands.

• paratrophy dystrophy.

• paratuberculosis [par″ -too-bur″ku-lo′sis] see Johne’s disease.

• paratyphoid [par″ -ti′foid] infection with any Salmonella sp. other than S. typhi in humans. See salmonellosis.

  • p. nodule very small, yellow, necrotic foci in the liver in calves and pigs with salmonellosis.

• paraurethral [par″ -u-re′thr l] near the urethra.

• paravaccinia [par″ -vak-sin′e-] a synonym for Parapoxvirus.

• paravaginitis [par″ -vaj″ľ-ni′tis] inflammation of the tissues alongside the vagina.

• paravertebral [par″ -vur′t-br l] near the vertebrae.

  • p. ganglia postganglionic sympathetic neurons synapse in these ganglia close to the aorta.
  • p. block see paravertebral block.

• paraveterinary allied to the veterinary profession. See paraprofessional.

• parbendazole [par-ben′d -zōl] a broad-spectrum benzimidazole anthelmintic effective against the common parasites of cattle, pigs and horses. It acts quickly, reaching peak blood concentrations 6–8 hours after administration. Its use in pregnant animals is contraindicated because of its teratogenicity; the defects are largely skeletal. Like other benzimidazoles, it suffers from the problem of resistance developing in the resident worm population if it is used persistently.

• paregoric [par″ -gor′ik] opium tincture; a mixture of powdered opium, anise oil, benzoic acid, camphor, and glycerin, in diluted alcohol, previously used as an antiperistaltic, especially in the treatment of diarrhea.

• parelaphostrongylosis see Parelaphostrongylus tenuis.

• Parelaphostrongylus [p -rel″ -fo-stron′jľ-lus] a genus of nematodes belonging to the family Protostrongylidae, in the superfamily Metastrongyloidea, which contains the ‘lungworms’.

  • P. andersoni found in the musculature, especially in the longissimus dorsi, in white-tailed deer.

    P-15.

    

    The parasympathetic nervous system. The preganglionic neuron releases acetylcholine at the nicotinic receptors. The postganglionic neuron releases acetylcholine at the muscarinic receptors of the target organ

  • P. odocoilei found in connective tissue around blood vessels and lymphatics of musculature below the vertebral column, abdomen, and proximal parts of the limbs in mule and black-tailed deer and in moose.
  • P. tenuis (syn. Pneumostrongylus tenuis, Odocoileostrongylus tenuis, Elaphostrongylus tenuis, Neurofilaria cornelliensis) found in the cranial venous sinuses of white-tailed deer but is nonpathogenic in this species. Infection also occurs in moose, elk, caribou, red deer, black-tailed deer, llama, sheep, and goat. In these species, the migrating larvae cause serious damage in the spinal cord and posterior paralysis, often in a number of animals at the one time. Called also moose sickness. Some infected goats also develop a local, linear dermatosis over the shoulders, thorax, and flanks, believed to be caused by migrating P. tenuis larvae irritating nerve roots that leads to pruritus and self-trauma along dermatomes.

• parenchyma [p -reng′kľ-m] the essential or functional elements of an organ, as distinguished from its stroma or framework.

• parenchymatitis [par″ ng-kim″ -ti′tis] inflammation of a parenchyma.

• parent generation the immediate parents of the F₁ generation. Denoted by P₁.

• parentage the animal’s sire and dam. In animal circles, the dam is usually evident, the sire is often a subject of conjecture.

  • p. determination see parentage testing (below).
  • p. exclusion testing see parentage testing (below).
  • p. testing a test using DNA profiling, also called DNA fingerprinting, to determine whether two individuals are biologically parent and offspring. DNA profiling via microsatellites or restriction fragmentlength polymorphisms (RFLPs) are the most advanced and accurate technologies to determine parentage. Offspring can only have alleles possessed by one or both of its parents; therefore, identification of the offspring’s alleles allows exclusion of some possible sires because they carry alleles not possessed by the potential sire. Called also parentage determination, parentage exclusion testing, and paternity testing.

• parental [p -ren′t l] emanating from or pertaining to a parent.

• parenteral [p -ren′tr- l] not through the alimentary canal, e.g., by subcutaneous, intramuscular, intrasternal or intravenous injection, e.g., parenteral fluid therapy.

  • p. alimentation see parenteral nutrition (below).
  • p. hyperalimentation see parenteral nutrition (below).
  • p. nutrition the provision of adequate carbohydrate, protein, vitamins, minerals, and fluids parenterally to maintain the animal over a relatively long period of several weeks. Called also parenteral alimentation, parenteral hyperalimentation. See also parenteral nutrition.
  • p. therapy treatment by the parenteral route is limited to those substances that are soluble in a solvent that can be injected into tissues including the bloodstream. The choice of routes may depend on the nature of the vehicle used, e.g., oily preparations are injected into tissues, irritant substances are injected intravenously slowly.

• parepididymis [par″ep-ľ-did′ľ-mis] paradidymis.

• parer see hoof knife.

• paresis [p -re′sis] weakness as a result of neurological or muscular disease with motor function still present. Includes the animals that can make purposeful attempts to rise without being able to do so, those that are able to rise with assistance, those that are able to rise and walk with major difficulty including frequent falling, and those able to stand and walk without assistance but with slight errors, e.g., stumbling.

  • hypocalcemic p. a stage or form of hypocalcemia in which the patient remains ambulatory. See parturient hypocalcemia fever, ovine hypocalcemia.
  • inherited spastic p. a suspect inherited defect of cattle that appears several months after birth and occurs in most breeds of cattle. A hindleg is stiff and straight on rising, with the limb thrust out behind, and the hoof does not reach the ground. After several minutes, the gastrocnemius muscle relaxes and the animal walks normally, although the leg is still abnormally straight. Gradually the stiffness worsens until the animal is unable to walk. Called also Elso heel, so named after a bull of that name believed to have been the genetic source of the defect in Holstein cattle.

    P-16.

    

    Calf with spastic paresis

  • parturient p. see parturient hypocalcemia.
  • progressive canine p. see dural ossification, degenerative myelopathy of German shepherd dogs.

• paresthesia [par″es-the′zh ] morbid or perverted sensation; an abnormal sensation, as burning, prickling, formication, etc., Difficult to define in animals because of its subjectivity. Sensations that give rise to itching or rubbing in animals are probably best classified as pruritus.

• pargyline a monoamine oxidase inhibitor, used to treat hypertension.

• Parhadjelia neglecta a habronematid nematode found in the proventricular submucosa of ducks in Brazil.

• pari-mutuel, parimutuel betting on the totalizator. Literally means betting between ourselves. All of the money wagered is divided up equally between those who have backed the winning and placed horses.

• paries [par′e-ēz] pl. parietes [L.] wall of an organ (e.g., hoof) or cavity (e.g., abdomen).

  • p. labyrinthicus, p. mastoideus, etc. medial wall of the middle ear that separates it from the internal ear.

• parietal [p -ri′-t l] 1. of or pertaining to the walls of an organ or cavity. 2. pertaining to or located near the parietal bone.

  • p. block abnormal electrical conduction through the left branch of the bundle of His.
  • p. bone one of two quadrilateral bones forming the sides and roof of the cranium. See Table 9.
  • p. cells cells of the proper gastric mucosa that secrete hydrochloric acid. Called also oxyntic cells.
  • p. decidua see parietal decidua.
  • p. hernia when only the antimesenteric edge of the intestine is incarcerated in the defect of body wall or mesentery.
  • p. lobe the upper central portion of the cerebral hemisphere, between the frontal and occipital lobes, and above the temporal lobe. In the human brain, it is the receptive area for fine sensory stimuli, and the highest integration and coordination of sensory information is carried on in this area. Damage to the parietal lobe can produce defects in vision and aphasia.
  • p. peritoneum, p. pleura that part of the serous membrane that invests the wall of the cavity, as distinct from the visceral part.

• parietofrontal [p -ri″-to-frun′t l] pertaining to the parietal and frontal bones, gyri, or fissures.

• parietography radiographic visualization of the walls of an organ.

• Parinaud’s oculoglandular syndrome [pah-re-no′] a unilateral granulomatous conjunctivitis associated with preauricular and

• Paris green an old-fashioned green pigment used in plaster and still found in old buildings. Can cause inorganic arsenic poisoning.

• Parisian frill a large canary characterized by a mass of frilled feathers which appear to completely cover the body.

• parity [par′ľ-te] 1. para; the number of times that an animal has been pregnant and has given birth, e.g., a parity 3 dairy cow is one that has calved three times and is in her third lactation. 2. equality; close correspondence or similarity.

• Parker–Kerr suture pattern [pahr′k r] one used to close the stump of a hollow viscus, e.g., in intestinal anastomosis. A Cushing suture pattern is put in first over the top of the bowel clamp that is then gradually withdrawn and the suture pulled tight. A layer of Lembert pattern is then used to oversew the first row.

• Parker retractor [pahr′k r] a shaped piece of flat metal with rounded ends both of which are curved back against the main blade. Used for holding a laparotomy incision open.

• Parkinsonia aculeata [pahr″kin-so′ne- n] plant in the legume family Caesalpiniaceae; causes nitrate–nitrite poisoning; called also horse bean, Jerusalem thorn, retama.

• paroccipital [par″ok-sip′ľ-t l] near the occipital bone.

• paromomycin [par′ -mo-mi″sin] a broad-spectrum aminoglycoside antibiotic derived from Streptomyces rimosus var. paromomycinus; poorly absorbed after oral administration, it is used for the treatment of bacterial and protozoal enteric infections.

• paromphalocele [par′om′f -lo-sēl″] hernia near the navel.

• paronychia [par″o-nik′e- ] inflammation involving the folds of tissue surrounding the nail or claw. Causes much pain and often results in loss of the nail or abnormalities in its growth such as grooves, discoloration, or fragility. Called also perionychia, perionychitis.

  P-17.

  

  Paronychia in a cat caused by Microsporum canis

• paroöphoron [par″o-of′ -ron] an inconstantly present, small group of coiled tubules between the layers of the mesosalpinx, being a remnant of the excretory part of the mesonephros.

• parophthalmia [par″of-thal′me- ] inflammation of the connective tissue around the eye.

• parorchidium [par″or-kid′i- m] displacement of a testis or testes.

• parosteal [par-os′te- l] pertaining to the outer surface of the periosteum, e.g., parosteal osteosarcoma.

• parostosis [par″os-to′sis] ossification of tissues outside of the periosteum.

• parotid [p -rot′id] near the ear.

  • p. adenitis inflammation of the parotid gland characterized by regional swelling, pain, and heat.
  • p. duct see parotid glands (below).
  • p. duct transposition a surgical procedure in which the parotid duct is redirected so that it discharges into the lower conjunctival cul-de-sac. Used in the treatment of keratoconjunctivitis sicca.
  • p. glands the largest of the main pairs of salivary glands, located on either side of the head, just behind the jaw and below the ears. From each gland a duct, the parotid duct, runs forward across the cheek (carnivores and small ruminants) or runs on the inside of the jaw to wind around the ventral border of the jaw to the cheek (pig, horse, and ox) and opens on the inside surface of the cheek generally opposite the upper molars, the precise location depending on the species.
  • p. region the region below the ear.

• parotidectomy [p -rot″ľ-dek′t -me] excision of a parotid salivary gland.

• parotiditis, parotitis [p -rot″ľ-di′tis] inflammation of the parotid gland.

  • contagious p., epidemic p. mumps, an acute, communicable viral disease of humans involving chiefly the parotid gland, but frequently affecting other oral glands or the pancreas or gonads.

• parous [par′ s] having produced offspring.

• parovarian [par″o-var′e- n] 1. beside the ovary. 2. pertaining to the parovarium (epoophoron).

  • p. cyst developmental remnants of the mesonephric duct system; thin-walled sacs distended with clear fluid located in the mesosalpinx and the infundibulum of the oviduct. They appear to have no effect on fertility.

• parovarium [par″o-var′e- m] epoöphoron.

• paroxetine [p -rok′s -tēn] a selective serotonin reuptake inhibitor used in the treatment of behavioral problems in dogs and cats.

• paroxysm [par′ok-siz- m] 1. a sudden recurrence or intensification of clinical signs. 2. a spasm or seizure.

• paroxysmal [par″ok-siz′m l] having the characteristic of a paroxysm.

  • p. syndrome clinical neurological signs not due to lesions within the nervous system, but involving abnormal neurotransmitter function. Includes Scotty cramp, episodic falling of Cavalier King Charles spaniels, and narcolepsy.

• parr a juvenile salmonid, especially Salmo spp., at a stage before it becomes a smolt; characterized by parallel transverse bands on its sides.

• PARR (PCR for antigen receptor rearrangement). A test performed on body fluid or tissue aspirates that uses PCR to amplify the variable regions of immunoglobulin genes and T-cell receptor genes from lymphoid cells in order to differentiate inflammation from cancer; it can detect the presence of a clonal population (cancer) and determine the T- or B-cell phenotype of lymphoma and lymphoid leukemias.

• parrot birds of the order Psittaciformes; which is divided into three super-families: Psittacoidea (true parrots); Cacatuidae; and Strigopoidea (NZ parrots). All are characterized by curved beaks. The typical parrots are the macaws, parakeets, lovebirds, and budgerigars. They are characterized by their bright plumage, their gift of mimicry, and their popularity as pets.

  • p. fever see psittacosis.
  • p. mouth serious malocclusion of the incisors with the upper arcade protruding beyond the lower. Called also overshot. See also brachygnathism.
  • p. pox see parrotpox.

• parrotpox a pox disease caused by a poxvirus in the genus Avipoxvirus. Occurs in South American and Australian psittacine birds. several symdromes recognized; ‘dry’ pox, as dry scabs around the mouth, eyelids, face, and legs; ‘wet’ pox, or diphtheritic, form with white plaques in the oral cavity and with blunting of the choanal papillae; a septicemic form; and a form where viral induced neoplastic lesions develop.

• pars pl. partes [L.] a division or part.

  • p. ciliaris retinae the dual epithelial layer lining the ciliary body.
  • p. distalis the major part of the anterior lobe of the pituitary gland, the adenohypophysis. It is separated from the neurohypophysis by the intraglandular cleft, the residual lumen of Rathke’s pouch.
  • p. disseminata the thin layer of the prostate that surrounds the urethra; as distinct from the body of the gland.
  • p. flaccida the small, triangular portion of the tympanic membrane lying between the lateral process of the malleus and the margins of the tympanic incisure.
  • p. infundibularis the neural stalk that connects the neurohypophysis with the hypothalamus.
  • p. intermedia the part of the adenohypophysis consisting of a layer of cells contiguous with the neurohypophysis. The source of melanocyte-stimulating hormone.
  • p. iridica retinae the dual epithelial layer lining the posterior aspect of the iris.
  • p. longa glandis the long, cylindrical part of the dog’s glans penis; distinct from the bulbar part.
  • p. major uteri the section of the bird’s oviduct in which the egg is held while the shell is formed.
  • p. mastoidea the mastoid portion of the temporal bone, being the irregular, posterior part.
  • p. nervosa of the pituitary gland. See neurohypophysis.
  • p. optica retina the major part of the retina that contains the neurosensory elements extending from the ora to the optic nerve head.
  • p. petrosa the petrous portion of the temporal bone, containing the inner ear.
  • p. pigmentosa the pigmented part of the retina; the retinal pigment epithelium.
  • p. plana the thin flat part of the ciliary body; the orbicularis ciliaris.
  • p. plicata the folded part of the ciliary body; corona ciliaris.
  • p. pylorica distal segment of the stomach or abomasum, curved behind the omasum.
  • p. pylorica ventriculi the distal (aboral) third of the stomach.
  • p. squamosa the flat, scale-like, anterior and superior portion of the temporal bone.
  • p. tensa the drumlike part of the tympanic membrane.
  • p. tuberalis a layer of cells surrounding the neural stalk of the pituitary gland and forming part of the adenohypophysis.
  • p. tympanica the tympanic portion of the temporal bone, forming the anterior and inferior walls and part of the posterior wall of the external acoustic meatus.

• parsley see Petroselinum, Chaeophyllum, Aethusa, Cymopterus.

• Parson Russell terrier a small (13–17 lb), very active dog, with a short, smooth- or wire-haired (broken, rough) coat in white with tan or black markings or tricolor. The ears are small and dropped, and tail may be docked. There is a confusing variation in names applied to a range of similar, small working terriers in different countries, this one being recognized by the American Kennel Club and the UK Kennel Club for dogs that are called by others as Jack Russell terrier and sometimes the Parson Jack Russell terrier, although those may vary slightly in their breed standard, particularly in body size, length of legs, and texture and length of coat. The ‘group’ is affected by an inherited form of myasthenia gravis and a progressive ataxia.

• part–film distance [pahrt] the distance between the part being x-rayed and the film; the greater the distance the less definition of the image. See object–film distance.

• Parthenium hysterophorus plant member of Asteraceae family; contains a sesquiterpene lactone that causes hepatopathy, dermatitis, stomatitis, nephropathy. Called also parthenium weed.

• Parthenocissus quinquefolia garden plant in the family Vitaceae; contains unidentified toxin poisonous to birds. Called also Virginia creeper.

• parthenogenesis [pahr″th -no-jen′ -sis] asexual reproduction in which an egg develops without being fertilized by a spermatozoon, as in certain lower animals, especially arthropods; it may occur as a natural phenomenon or be induced by chemical or mechanical stimulation (artificial parthenogenesis).

• parti-color variegated in two or more colors; used to describe coat color in dogs.

• partial pertaining to or having the characteristics of a part of something.

• particulate [pahr-tik′u-l t] composed of separate particles.

• parting of hair where hairstreams of hair diverge, exposing the skin.

• partridge two genera of gallinaceous game birds (Perdix, Alectoris) in the pheasant family Phasianidae. They are ground feeders and tree perchers. They are poor flyers but can run quickly when disturbed. The common species are the red-legged and the common partridges.

• parts per million mg/kg or ml/L; see ppm.

• parturient [pahr-tu′re- nt] giving birth or pertaining to birth.

  • p. disease disease related to parturition that occurs during or in close relationship to parturition.
  • p. injury injury sustained during birth, to the neonate or to the dam, not necessarily restricted to the birth canal or even the reproductive system, e.g., hip dislocation.
  • p. paresis see parturient hypocalcemia.
  • p. recumbency recumbency in a female that has just borne young. May be due to hypocalcemia, toxemia, physical injury or to being unable to find suitable footing.

• parturiometer [pahr″tu-re-om′ -t r] a device used in measuring the expulsive power of the uterus.

• parturition [pahr″tu-rľ′sh n] the act or process of giving birth to a calf, foal, lamb, puppy, etc.

  • p. acceleration used most commonly in sows with uterine inertia; usual medication is oxytocin; carazolol a recent introduction to the list. Also called p. augmentation.
  • p. delaying attempted to give more time for relaxation of the cervix; clenbuterol the common medication.
  • difficult p. see dystocia.
  • p. induction is a common management practice in dairy herds in order to synchronize calvings and lactations. It is also used for therapeutic reasons when large fetuses are expected or in sows when mastitis–metritis–agalactia is a problem in the herd. The usual method is the injection of a suitable corticosteroid, oxytocin, or PGF_2α. Undesirable side–effects include high calf mortality rate, retained placenta, photosensitive dermatitis and unusual metabolic diseases. Called also calving induction, parturition initiation.
  • p. initiation see parturition induction (above).
  • p. injury includes laceration of the cervix, vaginal wall or vulva, uterine rupture, fat hernia through the vaginal wall, uterine prolapse, rupture of middle uterine artery, sciatic nerve injury, maternal obstetric paralysis.
  • prolonged p. prolongation of parturition beyond the normal for the species is attended by risks to the dam and the fetuses.
  • p. psychosis see farrowing hysteria.
  • synchronized p. control of the date of parturition by controlling the date of estrus and of mating, or by the induction of parturition.

• parulis [p -roo′lis] a subperiosteal abscess of the gum originating from a periapical infection; called also gum boil.

• parumbilical [par″ m-bil′ľ-k l] alongside the navel.

• parvaquone an antiprotozoal agent.

• parvicellular [pahr″vľ-sel′u-l r] composed of small cells.

• parvo [pahr″vo] slang for parvovirus infection.

• parvoviral [pahr′vo-vi″v l] pertaining to a parvovirus.

• Parvoviridae [pahr″vo-vir′ľ-de] a family of small (20 nm diameter) icosahedral single-stranded DNA viruses that are nonenveloped. There are three genera of veterinary importance: Parvovirus, which includes feline panleukopenia virus, mink enteritis virus, canine, bovine, and porcine parvoviruses and Aleutian mink disease virus; Densovirus, which occur in insects; Erythrovirus, which infect primates; and Dependovirus, which are defective, requiring adenoviruses to complete their replication, and are nonpathogenic (called also adeno-associated viruses). Autonomously replicating parvoviruses replicate only during S phase of the cell cycle, i.e., they attack dividing cells.

• parvovirus [pahr′vo-vi″r s] a virus of the family Parvoviridae, sub-family Parvovirinae.

  • bovine p. a Bocavirus of the family Parvoviridae that commonly infects the intestinal tract of cattle, but does not cause clinical disease.
  • canine p. type 1 (CPV1) is not associated with clinical disease. Called also minute canine virus (MCV).
  • canine p. type 2 (CPV2) the cause of enteritis and a panleukopenia-like disease in dogs, particularly puppies. Clinical signs include vomiting and diarrhea, often with blood, high fever, dehydration, and a leukopenia. Perinatal or in utero infection may result in generalized disease or acute myocarditis. There is a high mortality rate in young puppies, but vaccines are available for prevention of the disease. The original parvovirus (CPV-2) was joined by an antigenic variant, CPV-2a in the early 1980s and a second variant, CPV-2b, emerged soon after. A strain, CPV-2c, has been reported in Europe, Asia, and South America.
  • feline p. see feline panleukopenia.
  • porcine p. a cause of stillbirths, abortion, mummification, embryonic death, and infertility in young sows (SMEDI), which become infected with a parvovirus in early gestation.

• PAS 1.p-aminosalicylic acid, used at one time in the treatment of tuberculosis in humans; also abbreviated PASA. 2. periodic acid–Schiff stain.

• pas-de-côte the sidestep in equine dressage.

• pascal (Pa) the SI unit of pressure, which corresponds to a force of one newton per square meter.

• Pascalia glauca see Wedelia glauca.

• Paschen bodies, Paschen’s corpuscles inclusion bodies in the cells of tissues infected with vaccinia or variola viruses.

• Paso a Spanish breed of horse that has given rise to related breeds through the Americas. Characterized by a smooth, even, four-beat symmetrical gait done at varying speeds, known as the paso.

• paspalitrems tremorgens produced by Claviceps paspali that parasitize Paspalum spp. grasses.

• Paspalum [pas′p -l m] a grass genus of the Poaceae family, containing a number of valuable pasture grasses, all of which are capable of causing poisoning if Claviceps paspali (paspalum ergot) infests their seed heads; includes P. commersonii, P. compressum, P. conjugatum (hilograss), P. dilatatum (paspalum, Dallis grass), P. distichum (P. vaginatum, knotgrass, salt water couch), P. notatum (bahiagrass), P. orbiculare (ditch millet), P. paspalodes (water couch), P. scrobiculatum (kodomillet), P. urvillei (water couch).

• paspalum ergot [pas′p -l m] the ergot fungus that grows on the seedheads of members of the Paspalum genus of grasses. See also paspalum staggers. Two different species can be involved, Claviceps paspali or C. cinerea.

• paspalum grass [pas′p -l m] see Paspalum.

• paspalum staggers [pas′p -l m] caused by the ingestion of paspaltrems in Claviceps paspali, C. cinerea, the ergot of Paspalum. Characterized by ataxia, gross muscular tremor, frequent falling, hypermetria, hyperesthesia. Recovery is spontaneous.

• passage [pas′ j] introduction followed by recovery of an infectious agent in an experimental animal or culture medium.

  • blind p. passage of an infectious agent through an experimental animal or medium without there being any evidence, clinical or cultural, that the agent is present.
  • serial p. repeated passage through a series of experimental animals or media, often with the objective of altering the virulence of the agent or adapting it to grow better.

• Passalurus a genus of nematodes in the family Oxyuridae.

  • P. ambiguus found in the cecum and colon of rabbits, hares, and other lagomorphs. They appear to be harmless even in very large numbers.

• Passeriformes the largest order of birds including all of the 5500 or more perching birds, including the finches, sparrows, buntings, mynahs, canaries, and serins.

• passerines [pas′ r-ins] birds belonging to the order Passeriformes, includes over half of all bird species.

• Passeromyia a genus of screw-worm flies of birds; parasitizes nestlings.

• Passiflora [pas″ľ-flo′r ] a plant genus of vines in the family Passifloraceae. Includes P. edulis (passion fruit, granadilla) and P. mollissima (babana passion flower) valued for their edible fruits. Most of the plants in the genus that have been tested have high concentrations of cyanogenetic glycosides and are potential causes of cyanide poisoning, and there is good field evidence of poisoning of livestock by some of them. Suspected species are P. aurantia, P. cinnabarina, P. foetida, P. herbertiana, P. suberosa.

  • P. subpeltata contains an unidentified toxin causing clonic seizures and blindness in cattle. Called also P. alba, white or wild passion flower.

• passion flower see Passiflora.

• passivation [pas″ľ-va′sh n] the final stage in instrument manufacture, passing the finished instruments through a bath of nitric acid that removes foreign particles and promotes the formation of a protective coating of chromium oxide.

• passive [pas′iv] neither spontaneous on the part of the patient, nor active response by the patient, the stimulus having been applied externally.

  • p. cutaneous anaphylaxis (PCA) test see passive cutaneous anaphylaxis.
  • p. diffusion passage of electrolytes to all parts of a solution, including through a permeable membrane. Plays some part in intestinal absorption.
  • p. hemagglutination test see hemagglutination test.
  • p. immunization see passive immunization.
  • p. neonatal immunity see passive immunity.
  • p. transfer 1. see passive diffusion (above). 2. the transfer of immunoglobulins from the dam to the neonate; usually refers to colostral transfer. The immunity is passive, the transfer is not, being an energy dependent process. Correct term is transfer of passive immunity.
  • p. venous congestion noninflammatory distention of vessels with blood. Caused by simple accumulation resulting from obstruction or failure of the heart to eject the full volume of blood returned to it.

• paste [pāst] highly viscous or thick, moist preparation in which powder is mixed with a small amount of liquid.

• pastern [pas′t rn] in ungulates the segment of the limb between the fetlock and hoof, supported by proximal and middle phalanges; in dogs the metacarpal region.

  • equine p. dermatitis see greasy heel.
  • congenital p. flexure a common neonatal deformity in all species. If it is the only deformity it commonly corrects itself spontaneously or with minimal interference. Occurs also as part of multiple deformities, e.g., Akabane virus disease.
  • p. folliculitis folliculitis of the posterior pastern in horses from which Staphylococcus hyicus has been isolated.
  • p. joint in ungulates, the articulation between the proximal and middle phalanges. Called also proximal interphalangeal joint.
  • long p. bone first phalanx of ungulates; Called also large pastern bone, os compedale, os suffraginis, P1, proximal phalanx.
  • short p. bone second phalanx of ungulates. Called also small pastern bone, os coronale, middle phalanx, P2.
  • slack p. too much slope in the pastern.

• Pasteur [pahs-toor′] named after Louis Pasteur, French microbiologist and chemist.

  • P.–Chamberland filter see Pasteur–Chamberland filter.
  • P. effect the decrease in the rate of glycolysis and the suppression of lactate accumulation by tissues or microorganisms in the presence of oxygen.

• Pasteur–Chamberland filter [pahs-toor′] a hollow column of unglazed porcelain through which liquids are forced by pressure or by vacuum exhaustion.

• Pasteurella [pas″t r-el′] a genus of gram-negative facultatively anaerobic, rod-shaped bacteria. Commonly exhibit bipolar staining and often susceptible to penicllin G.

  • P. aerogenes found in pigs. A cause of wound infections from pig bites.
  • P. anatipestifer now classified as Riemerella anatipestifer.
  • P. anatis now classified as Gallibacterium anatis.
  • P. avium now classified as Avibacterium avium.
  • P. caballi causes respiratory infections in horses.
  • P. canis commensal in dogs. Can cause bite wound infections and also pneumonia in cattle and sheep.
  • P. dagmatis commensal of dogs and cats. Cause of bite wound infections.
  • P. gallinarum now classified as Avibacterium gallinarum.
  • P. granulomatis now classified as Mannheimia granulomatis.
  • P. haemolytica biotype A now classified as Mannheimia haemolytica and M. glucosida.
  • P. haemolytica biotype T now classified as Bibersteinia trehalosi.
  • P. langaaensis a commensal of birds
  • P. lymphangitidis a cause of lymphangitis in cattle.
  • P. mairii a cause of abortion in sows.
  • P. multocida the cause of hemorrhagic septicemia in cattle, sheep, and pigs, fowl cholera of birds, pasteurellosis of rabbits, and gangrenous mastitis of ewes. It is also commonly found in atrophic rhinitis of pigs. Divided into three subspecies, gallicida, multocida, and septica, but these do not appear to have any host species predilection. Also classified into capsular serotypes types A, B, D, E, and F.
  • P. oralis cause of dog and cat bite wound infections. A commensal of the oral cavity of multiple animal species.
  • P. pestis now classified as Yersinia pestis.
  • P. piscicida now classified as Photobacterium damselae subsp. piscicida.
  • P. pneumotropica now classified as Rodentibacter pneumotropicus.
  • P. salpingitidis now classified as Actinobacillus salpingitidis.
  • P. skyensis cause of mortalities in farmed Atlantic salmon.
  • P. species A now classified as Avibacterium species A. Cause of sinusitis and conjunctivitis in birds.
  • P. species B now classified as P. oralis.
  • P. stomatis commensal in dogs and cats, but can cause bronchitis in dogs and wound infections.
  • P. testudinis associated with respiratory disease in tortoises.
  • P. trehalosi now classified as Bibersteinia trehalosi.
  • P. tularensis now classified as Francisella tularensis.
  • P. volantium now classified as Avibacterium volantium.

• Pasteurellaceae [pas″t r-el-a′se-e] a family of gram-negative, facultatively anaerobic, relatively fastidious rod-shaped bacteria that are mostly commensals of mucosal surfaces but are capable of causing opportunistic infection and disease. Includes the genera Haemophilus, Actinbacillus, Pasteurella (hence sometimes called the HAP group), Aggregatibacter, Avibacterium, Bibersteinia, Gallibacterium, Histophilus, Glaesserella, and Mannheimia.

• pasteurellosis [pas″t r- -lo′sis] infection with organisms of the genera Pasteurella and Mannheimia. In animals, includes septicemic pasteurellosis, pneumonic pasteurellosis, both of cattle, snuffles in rabbits, and pasteurellosis of swine, sheep, and goats. The causative bacteria include P. multocida types A, B, C, and D, and M. haemolytica. Infection in humans often occurs as a result of dog and cat bites.

  • epidemic p. see hemorrhagic septicemia.
  • ovine, porcine and caprine p. the more common pneumonic disease is caused by M. haemolytica and the septicemic disease by P. trehalosi.

• pneumonic p. the common pasteurellosis of cattle caused by Mannheimia haemolytica serotype A1 and A6 (shipping fever) and sometimes Pasteurella multocida type A (enzootic pneumonia calves). Occurs in weaned beef calves recently placed in feedlots (shipping fever) and unweaned dairy calves (enzootic pneumonia). Characterized by acute bronchopneumonia with fever, dyspnea, abnormal breath sounds, weak cough, severe toxaemia, and death in 24–48 hours.

  • septicemic p. see hemorrhagic septicemia.

• pasteurization [pas″ch r-ľ-za′sh n] the process of heating milk to destroy pathogenic microorganisms and delay the development of spoilage organisms. The holding method heats milk to at least 62.8°C (145°F) and holds it at that temperature for not less than 30 minutes. Hightemperature short-time (HTST) pasteurization heats to 71.7°C (161°F) for at least 15 seconds. Ultrapasteurization heats to 88.3°C (191°F) for 1 second or 100°C (212°F) for 0.01 seconds.

• Pasteurized Milk Ordinance (PMO) regulations approved by the Food and Drug Administration (US) governing the design and maintenance of dairy farms and processing and packaging plants to make sanitation and milk quality uniform across state lines. see also Grade A milk.

• Pastinaca sativa the domestic parsnip; causes primary photosensitization, due to furocoumarin produced in response to the fungal or bacterial infection of the plant.

• pastoral emanating from or pertaining to the use of land for pasture.

  • p. rearing raising of young, after weaning, on pasture where they are more susceptible to nutritional deficiencies and parasitic infestation than young reared indoors.

• pasture fields or paddocks carrying a permanent or semipermanent growth of grasses and clovers or other legumes and usually some volunteer herbaceous plants. It is used as a complete or partial diet for herbivores and in some economies for omnivores. It may be permanent or temporary, even annual, irrigated or dry, native or improved.

  • clean p. refers to the status of the pasture as a source of infective helminth larvae and implies relative freedom. The degree of freedom from parasite larvae is important as a factor in prevention of parasitoses.
  • p. ley see ley.
  • p. meter device for measuring the amount of feed remaining; based on a design in which a flat metal plate traverses up a central spindle when the spindle is inserted through the plants so that it reaches the ground, the plate floating on top of the plants; measures in cow days.
  • native p. consists of the plants normally found growing wild in the area. Agriculturally speaking, this usually refers to areas with an annual rainfall of less than 20 in. (500 mm). Areas with larger rainfalls usually carry improved pastures.
  • p. plants plants which occur naturally or are cultivated especially for growing in pasture to provide feed for grazing animals, with excess growth made into hay or ensilage.
  • p. rotation see rotational grazing.

• pasturing the system of management based on the use of pasture as the principal source of dietary energy.

• pasveer process the channel aeration method of sewage disposal in which the effluent is passed along deep channels 3 to 7 ft deep to undergo aeration.

• patagia sheets of skin where the neck, wings, and legs join the body. The main components of the wing patagia are the propatagium between the shoulder and carpus, and the metapatagium between the thorax and wing.

• patagiectomy [p -ta″zhe-ek′t -me] excision of a section of the patagia, the propatagium, or wing membrane. A surgical procedure performed on one side to prevent flight in large captive birds.

• patagium the strip of skin on each side of body that stretches between the front and hind legs of sugar gliders; called also gliding membrane.

• patch [pach] circumscribed flat area of skin changes >1 cm in diameter.

  • p. grafting see patch graft.
  • serosal p. creation of an adhesion between serosal surfaces in order to cover a defect or perforation of bowel, often accomplished by suturing another section of bowel over the area.
  • p. test a test of contact hypersensitivity in the skin. The test substance is applied to the skin, either under a dressing (closed patch test) or without a covering (open patch test). The site is examined at regular intervals for 3–5 days to detect any inflammatory reaction of the skin.

• patching antibody induced clustering of plasma membrane molecules, usually proteins or glycoproteins. Patching can also be induced by lectins.

• patella pl. patellae [L.] a large sesamoid bone at the femorotibial joint. See also Table 9.

  • p. cubiti an anomalous sesamoid over the extensor aspect of the elbow; commonly seen in bats.

• patellar of or pertaining to the patella.

  • p. cartilage a cartilaginous process borne on the medial side of the patella of horses and cattle.
  • p. fossa the depression in the anterior face of the vitreous humor in which the lens sits. Called also hyaloid fossa.
  • p. ligament the continuation of the central portion of the tendon of the quadriceps femoris muscle distal to the patella, extending from the patella to the tuberosity of the tibia; it is single in carnivores, pigs and sheep and trifurcated in horses and cattle, the medial being the largest of the three. Called also patellar tendon.
  • p. ligament desmotomy section of the medial patellar ligament for relief of upward luxation of the patella in horses (and rarely, cattle).
  • p. luxation, p. dislocation a common, congenital, or acquired orthopedic abnormality in dogs, causing mild to severe, continuous, or intermittent lameness. Medial luxation is more common in toy or miniature breeds, often as an inherited defect and frequently associated with structural abnormalities of the distal femur and proximal tibia. Lateral luxation is less frequent, and occurs more often in large breeds associated with genu valgum. Upward luxation and fixation in cattle presents with temporary or permanent stiffness and extension of the affected hindlimb and the animal drags the tip of the toe. More common in Brahman cattle. The cause is not known. Correction is by medial patella desmotomy. Not common in foals and when seen usually in miniature horse foals. May be unilateral or bilateral and intermittent or complete. Most commonly occurs in a lateral direction.

    P-18.

    

    Lateral radiograph of a normal canine stifle

    P-19.

    

    Bilateral congenital patellar luxation

  • p. reflex involuntary contraction of the quadriceps muscle and jerky extension of the stifle when the patellar ligament is sharply tapped. It is often used as a test of nervous system function. Absence of the reflex, together with deficient muscle tone in the limb, suggests paralysis or paresis of the limb due to a lower motor neuron lesion affecting the femoral nerve. Called also quadriceps reflex.
  • p. tendon see patellar ligament (above).

• patellectomy [pat″ -lek′t -me] excision of the patella.

• patelliform [p -tel′ľ-form] shaped like a small plate.

• patellofemoral [p -tel″o-fem′-r l] pertaining to the patella and femur.

• patency [pa′t n-se] the condition of being open.

• patent [pa′t nt] 1. open, unobstructed, or not closed. 2. apparent, evident.

  • p. ductus arteriosus (PDA) abnormal persistence of the left sixth aortic arch after birth leaving an open lumen in the ductus arteriosus, between the descending aorta and the pulmonary artery. The ductus arteriosus is open during prenatal life, allowing most of the blood of the fetus to bypass the lungs, but normally this channel closes shortly before birth. When the ductus arteriosus remains open, it places special burdens on the left ventricle and causes a diminished blood flow in the aorta. May remain open for up to 5 days in foals. One of the most common congenital heart defects in dogs, but less common in cats. Causes a continuous ‘machinery’ murmur that is loud in systole, soft in diastole, and a ‘bounding’ pulse. Correction is commonly carried out in dogs by surgical ligation of the structure or, more recently, transcatheter occlusion using coil embolization or deployment of various self-expanding devices.
  • p. ductus venosus see ductus venosus.
  • p. foramen ovale see foramen ovale (1).
  • p. medicine a drug or remedy protected by a trademark, available without a prescription; often a secret remedy, not considered effective. Called also a nostrum.
  • p. period the period during a disease in which the causative agent can be detected by clinicopathological tests, e.g., for helminth eggs.
  • p. ventricular septum includes several entities characterized by incomplete closure of ventricular wall. Characterized by palpable cardiac thrill and audible pansystolic murmur on both sides of the chest at birth, accompanied by exercise intolerance and developing dyspnea at rest. See also ventricular septal defect.

    P-21.

    

    Patent ductus arteriosus (PDA) in a dog

  P-20.

  

  Testing the patellar reflex

• paternity testing see parentage testing.

• Paterson’s curse Echiumplantagineum.

• path [path] a course for a procedure, especially in statistical matters.

  • p. analysis an analytical method suitable for the study of multiple variables. It has the advantage over the usual stepwise multiple regression analysis in that it allows the epidemiologist to decide the order in which the independent variables enter the regression equations, thus improving the chance that the modeled sequence of events will approximate the pattern in nature.

• pathergasia [path″ r-ga′zhe-] mental malfunction, implying functional or structural damage, marked by abnormal behavior.

• pathergy [path′ r-je] 1. a condition in which the application of a stimulus leaves the organism unduly susceptible to subsequent stimuli of a different kind. 2. a more prominent and extensive tissue response to a noxious stimulus (e.g., hyperreactivity of the skin at sites of minor trauma such as a needle prick).

• pathfinder [path′fīnd- r] 1. an instrument for locating urethral strictures. 2. a dental probe for tracing the course of root canals.

• path(o)- word element. [Gr.] relationship to disease.

• pathoanatomical diagnosis [path″o-an″ -tom′ľ-k l] a diagnosis that defines the type and location of the disease without identifying the cause, e.g., polioencephalomalacia.

• pathobiology [path″o-bi-ol′ -je] pathology.

• pathoclisis [path″o-klis′is] a specific sensitivity to specific toxins, or a specific affinity of certain toxins for certain systems or organs.

• pathogen [path′o-j n] any disease-producing agent or microorganism.

  • p. risk factors risk factors dependent on the characteristics of the pathogen, e.g., virulence or persistence in the environment of a bacterium or virus.

• pathogenesis [path″o-jen′ -sis] the combination of mechanisms that operate at biochemical, cellular, anatomic, and physiologic levels to cause pathoanatomic lesions and clinical disease. Pathogenetic studies aim to elucidate these mechanisms and their interactions.

• pathogenic [path-o-jen′ik] capable of causing disease, e.g., bacteria, fungi, protozoa.

• pathogenicity [path″o-j -nis′ľ-te] the ability of a pathogenic agent to produce disease in a host. See also virulence.

• pathogeny [path-oj′ -ne] pathogenesis.

• pathognomonic [path″og-no-mon′ik] specifically distinctive or characteristic of a disease; denoting a sign or other indicant on which a diagnosis can be made.

• pathological, pathologic [path″o-loj′ľ-k l] pertaining to or emanating from pathology.

  • p. anatomy see morbid anatomy.

• pathologist [p -thol′ -jist] a specialist in pathology.

• pathology [p -thol′ -je] 1. the study of disease, in particular its pathogenesis, and diagnosis by accurate interpretation of the associated biochemical, cellular, and pathoanatomic changes. 2. the structural and functional manifestations of a disease.

  • clinical p. see clinical pathology.
  • comparative p. that which considers human disease processes in comparison with those of animals.
  • experimental p. the study of artificially induced pathological processes.
  • oral p. that which treats of conditions causing or resulting from morbid anatomical or functional changes in the structures of the mouth.
  • surgical p. the pathology of disease processes that are surgically accessible for diagnosis or treatment.

• pathomorphism [path″o-mor′fiz- m] perverted or abnormal morphology.

  P-22.

  

  Pectus excavatum in a dog. The xiphisternum is angled dorsally into the thoracic cavity

• pathonomia [path-o-no′me- ] the science of the laws of disease.

• pathophysiology [path″o-fiz″e-ol′ -je] the physiology of disordered function.

• pathway [path′wā] a course usually followed. In neurology, the nerve structures through which a sensory impression is conducted to the cerebral cortex (afferent pathway), or through which an impulse passes from the brain to the skeletal musculature (efferent pathway). Also used alone to indicate a sequence of reactions that convert one biological material to another (metabolic pathway).

  • biosynthetic p. the sequence of enzymatic steps in the synthesis of a specific end product in a living organism.
  • classical p. one of the two pathways of complement activation, initiated by antigen–antibody complexes and involving C1, C2, and C4. It leads to activation of C3 and the terminal pathway. See also alternate complement pathway.
  • coagulation p’s see coagulation pathways.
  • direct oxidative p. see pentose phosphate pathway (below).
  • Embden–Meyerhof p. see Embden–Meyerhof pathway.
  • final common p. 1. the motor neurons by which nerve impulses from many central sources pass to a muscle or gland in the periphery. 2. any mechanism by which several independent effects ultimately exert a common influence.
  • pentose phosphate p. a pathway of hexose oxidation alternative to glycolysis in which glucose-6-phosphate undergoes two successive oxidations by NADP, each producing NADPH, leading to the formation of a pentose phosphate. Called also the phosphogluconate pathway or hexose monophosphate shunt.
  • properdin p. alternative complement pathway.
  • -pathy word element. [Gr.] a disease or a system for treating a disease.

• patient [pa′sh nt] an animal that is ill or is undergoing treatment for disease.

  • p. data in veterinary records, details of the animal patient with sufficient detail to provide positive identification; as well, owner are necessary as a basis for legal responsibility for the animal and to provide a means of client communications, consent, and recovery of costs.
  • p. monitoring continuous or frequent periodic clinical assessment.

• patrilineal [pat″rľ-lin′e- l] descended through the male line.

• Patterdale terrier a small (12–13 lb) hunting dog with a short, coarse coat in black, red, chocolate, or black and tan. It has a broad head and ears that fold over; the tail is docked to a medium length. Called also Black fell terrier.

• patterns [pat′ rns] the distribution of cases of disease, production maxima, population density or other measurable variable, in time or space. It may be random, or it may be in a pattern that is helpful in suggesting a diagnosis.

  • p. generators populations of neurons that generate a standard pattern of movements, e.g., respiratory basic rate and rhythm, rumination, mastication, eructation; they are not self-initiating but require stimulation from the brain or a sensory input.

• patulin [pat′u-lin] a mycotoxin and antibiotic substance derived from a group of fungi, including Aspergillus, Byssochlamys nivea, and Penicillium spp. While not a particularly potent toxin, it is considered genotoxic, so potentially carcinogenic. It is found on damaged fruit such as apples and in grains such as barley, wheat, and corn.

• patulous [pat′u-l s] spread widely apart; open; distended.

• Paullinia cupana [paw-lin′e- ] a South American plant in the family Sapindaceae; contains caffeine; included are some herbal medicines that have poisoned dogs. Called also guarana.

• paunch [pawnch] see rumen.

• pause [pawz] an interruption, or rest.

• compensatory p. the pause after a premature ventricular systole that occurs as the result of the impulse from the normal pacemaker conducting to the ventricle during its refractory period.

• Pautrier microabscess [po-tre-a′] see Pautrier microabscess.

• PAVE Program for the Assessment of Veterinary Education Equivalence. See American Association of Veterinary State Boards.

• pavetamine the polyamine toxin which causes a myocarditis and sudden death syndrome in livestock in South Africa called gousiekte. See Fadogia homblei, Pachystigma, and Pavetta.

• Pavetta [p -vet′] an African plant genus in the family Rubiaceae; plants contain the polyamine toxin, pavetamine, which causes myocarditis and sudden death (gousiekte). Includes P. harborii, P. schumanniana. Called also pavettabossie, tonnabossie, gousiekte tree, poison bride bush.

• pavilionitis inflammation of the fimbriated end of the oviduct.

• Pavlovian conditioning see conditioning classical.

• Pavo see peafowl.

• paw [paw] foot; especially of carnivores and other digitigrade animals.

  • p. and mouth disease see paw and mouth disease.

• pawing a form of behavior in horses characterized by persistent use of one forelimb to dig in the ground, or to thump it, or to scratch at a fixed object such as a door; stimulated by subacute pain or as a stereotypic behavior in stabled horses. Can be also a sign of colic in horses, usually accompanied by other signs of the disease.

• pawpaw [paw′paw] see Carica papaya.

• PBPharmacopoeia Britannica (British Pharmacopoeia).

• Pb chemical symbol, lead (L. plumbum).

• PBB polybrominated biphenyl.

• PBFD psittacine beak and feather disease.

• PBG-D porphobilinogen diaminase.

• PBI protein-bound iodine.

• PBS phosphate buffered saline.

• PBZ phenylbutazone, a nonsteroidal anti-inflammatory drug.

  • p.c. [L.] post cibum (after meals). Abbreviation used in medical records and nursing notes.

• PCA passive cutaneous anaphylaxis.

• PCB polychlorinated biphenyl.

• PCD primary ciliary dyskinesia.

• PCG phonocardiogram.

• PCNB pentachloronitrobenzene.

• PCP pentachlorophenol.

• PCR¹ polymerase chain reaction. The amplification of a specific DNA sequence, termed target or template sequence, that is present in a complex mixture, by adding two or more short oligonucleotides, also called primers, that are specific for the terminal or outer limits of the template sequence. The template–primers mixture is subjected to repeated cycles of heating to separate (melt) the double-stranded DNA and cooling in the presence of nucleotides and DNA polymerase such that the template sequence is copied at each cycle. Thermostable polymerases such as those obtained from a hot springs bacterium Thermus aquaticus, commonly termed Taq polymerase, are used. At the end of 20–30 such cycles, the amplified target sequence, which may have been present in as few as a single copy in the original mixture, can be readily detected, for example, by electrophoresis and ethidium bromide staining in an agarose gel.

  • multiplex PCR the simultaneous amplification and detection of more than one specific template in a mixture by addition of more than one set of oligonucleotide primers.
  • nested PCR the primers used in the first round of amplification are replaced in a second round of amplification with a second set of primers that hybridize to a region located within the amplified sequence of the first PCR reaction. It can be used to increase the sensitivity and specificity of the reaction.
  • quantitative PCR a means for quantifying the copy numbers of template DNA present in the original mixture. Can be achieved by use of real-time PCR (see below) or by the addition of a known amount of a target sequence that is amplified by the same primer set but can be differentiated, usually by size, at the end of the reaction and that compete for amplification. More amplification of the target sequence indicates relatively fewer template molecules. By running multiple PCR reactions with differing known amounts of the target sequence, the copy number of template molecules can be estimated.
  • real-time PCR a method for the detection and quantitation of an amplified PCR product based on incorporation or unquenching of a fluorescent reporter dye; the fluorescent signal increases in direct proportion to the amount of PCR product produced and is monitored at each cycle, ‘in real time’, such that the cycle number at which a significant increase in the amount of PCR product is first detected inversely correlates with the initial amount of target template.
  • reverse-transcriptase PCR (RT-PCR) a PCR technique applied when the target sequence is RNA, such as viral RNA or messenger RNA. The reverse transcription reaction, in which complementary DNA (cDNA) is synthesized from an RNA template by reverse transcriptase, is performed before the conventional PCR reaction is carried out.

• PCR² protein–calorie ratio.

• PCT prothrombin consumption time.

• PCV packed-cell volume, the volume of packed red cells in milliliters per 100 ml of blood.

• PCV2 porcine circovirus 2.

• PD 1. pregnancy diagnosis. 2. predicted differences.

• Pd chemical symbol, palladium.

• pd potential difference; prism diopter.

• PD₅₀ the median protective dose of antiserum or vaccine; that which protects 50% of the animals challenged.

• PDA patent ductus arteriosus.

• PDGF platelet-derived growth factor; interacting with cell surface receptors and stimulating hydrolysis of inositol 1,4,5-triphosphate (IP₃).

• PDS polydioxanone suture.

• PDNS porcine dermatitis and nephropathy syndrome.

• PDW platelet distribution width.

• PE abbreviation for physical examination; used in medical records.

• PE4 see cyclonite.

• pea [pē] leguminous plants, members of the family Fabaceae. The plants may be used as green feed but are usually too succulent to make into hay. Silage is made from the crop residue after harvesting canning peas but is very subject to fungal infestation. Peas used for livestock feed include canning peas (Pisum sativum), field peas (P. sativum var. arvense), chick peas (Cicer arietinum), and cow peas (Vigna sinensis, syn. V. catjang, V. unguiculata). See also Lathyrus.

  • angular p., slender wild p. Lathyrusangulatus.
  • Austrian p. Pisumsativum var. arvense.
  • bluebush p. Crotalariaeremaea.
  • Brazilian glory p. Sesbaniapunicea.
  • Broughton p. Swainsonaprocumbens.
  • budda p. Aeschynomeneindica.
  • coral p., rosary p. Abrusprecatorius.
  • Darling p. specifically Swainsona greyana but used to refer to any Swainsona spp.
  • everlasting p. Lathyrussylvestris, L. latifolius.
  • flat p. Lathyrussylvestris.
  • flat-pod p. Lathyruscicera.
  • Gambia p. Crotalariagoreensis.
  • garden p. Pisumsativum.
  • grass p., green p., Indian p. Lathyrussativus.
  • gray swainson p. Swainsonacanescens.
  • p. hulls a source of dietary fiber in manufactured pet foods.
  • kaley p., wild winter p. Lathyrushirsutus.
  • perennial p. Lathyruslatifolius.
  • scurf p. Cullen spp.
  • singletary p. Lathyruspusillus, L. hirsutus.
  • p.-struck poisoning by Darling peas. See Swainsona.
  • sweet p. Lathyrusodoratus.
  • Tangier p. Lathyrustingitatus.
  • p. vine ensilage is made from the commercial green pea plants after harvesting and removal of pods. It is now more common to harvest pods from the standing crop, which livestock then graze. Ensilage can be poisonous. Lambs show nervous signs soon after birth, an abnormal gait and intermittent recumbency with exercise, and there are degenerative lesions in the cerebral and cerebellar cortices at autopsy.
  • wild p. Lathyrusincanus, L. sylvestris.

• peach the fruiting tree of the genus Prunus in the family Rosaceae. The leaves and pips of this and other members of the family contain cyanogenetic glycosides and are potentially poisonous. Engorgement on the fruit may cause lactic acidosis and in occasional cases an entire fruit lodges in the esophagus and obstructs it. Called also Prunus persica.

  • poison p. Trematomentosa. Called also peach-leaf poison bush.

• peach-leaf poison bush see Trema.

• peacock see peafowl.

• peafowl three species of the family family Phasianidae, dramatically colored and extremely long-tailed birds. Pavo cristatus, the Indian peafowl or blue peafowl, is native to the Indian subcontinent and introduced to many regions of the world; also known as the common peacock. Pavo muticus, the green peafowl or Java peafowl, is distributed through southeast Asia. The Congo peafowl (Afropavo congensis), native to the Congo Basin, is the other species of peafowl. The male is referred to as a peacock and the female a peahen.

• Péan forceps compression forceps with ratchet handles and long, wide, slightly bowed blades with longitudinal grooves.

• peanut [pē′nut] seed kernels of the plant Arachis hypogaea cultivated as a commercial crop. Made into peanut meal after the oil is extracted. The kernels and meal are subject to fungal growth and may cause aflatoxicosis. Called also groundnut.

  • p. hulls a source of supplementary fiber in manufactured pet foods; it is high in lignin.
  • p. meal residue after the extraction of peanut oil; a high protein (40–50%) feed supplement; low in methionine, lysine, and tryptophan. May be mixed with hulls when it becomes of less value because of the high (30%) of fiber.
  • p. oil a refined fixed oil extracted from peanuts; used as a solvent for drugs.

• pearl 1. a small medicated granule, or a glass globule with a single dose of volatile medicine, as amyl nitrite. 2. a rounded mass of tough sputum, as seen in the early stages of an attack of bronchial asthma.

  • p. disease calcification of the nodular lesions of pleural tuberculosis in cattle.
  • epidermic p’s rounded concentric masses of epithelial cells found in certain papillomas and epitheliomas and as epithelial remnants of the dental lamina in the gingiva and jaws where they may give rise to cysts and tumors. Called also epithelial pearls.
  • epithelial p’s see epidermic pearls (above).
  • keratin p. a concentrically laminated nodule of keratinized squames that occurs often in squamous cell carcinomas as a result of their dysplastic manner of growth. Called also squamous pearl.
  • squamous p. see keratin pearl (above).

• pearled a method of processing grain feeds to increase digestibility; the grain is hulled and broken into small, smooth, pearl-like pieces. A process more suited to human nutrition where the appearance of the grain is more important.

• PEARS porcine epidemic abortion and respiratory syndrome.

• Pearson’s chi-square test [pēr′s n] see chi-square test.

• Pearson saw [pēr′s n] a chain saw used in large animal obstetrics. It is safe in operation but limited to making cuts in a longitudinal direction.

• Pearson square [pēr′s n] a quick, simple method of calculating the amount of a supplement required to achieve the desired composition of a ration. Copies of tables of feed standards and feed compositions are necessary to carry out the sums involved.

• peat, peat moss formed from decayed vegetable matter, particularly sphagnum mosses, in a wetland area or bog. Used as bedding for housed cattle and horses and is very absorbent of water. With pigs, peat bedding is a risk factor for atypical mycobacteriosis.

  • p. scours chronic diarrhea in ruminants grazing pasture on peat-derived soils low in copper and/or high in molybdenum. See also copper (Cu) nutritional deficiency, molybdenum (Mo)

• pebulate a thiocarbamate preemergence herbicide of low toxicity. Heavy doses cause muscular weakness, recumbency, and weight loss. Banned for use in the European Union.

• peccary a small mammal of the genus Pecari, native to the Americas, resembling a miniature wild boar. It has a sacculated stomach. Farmed in some countries and also kept as pets.

  • p. flea Pulex porcinus.

• peck order the order of dominance established in a flock of birds and changed only by fighting. The concept is now transposed to all species and is of major importance where animals are kept in groups and have to compete for feed supplies and shelter.

• pecten [pek′t n] pl. pectines [L.] 1. a comb; comb-like structures. 2. a narrow zone in the anal canal, bounded cranially by the pectinate line (pectineus muscle and pubis).

  • p. oculi a black folded concertina-shaped trapezoidal structure attached to the optic disc of the fowl and other birds; of unknown function.
  • p. ossis pubis cranial edge of the two pubic bones; so named because of the comb-like fringe of the tendon of the rectus abdominis that inserts here.
  • pubic p. cranial edge of the pubis bone; provides attachment to the abdominal muscles; see pectin ossis pubis (above).
  • retinal p. a black pleated outgrowth from the retina to cover the optic papilla in the avian eye.

• Pecten yessoensis original name for Mizuhopecten yessoensis. A farmed scallop in the family Pectinidae; called also Japanese scallop.

• pectenitis [pek″t -ni′tis] inflammation of the pecten of the anus.

• pectenosis [pek″t -no′sis] stenosis of the anal canal due to an inelastic ring of tissue between the anal groove and anal crypts.

• pectin [pek′tin] a homosaccharidic polymer of sugar acids of fruit, which forms gels with sugar at the proper pH; a purified form obtained from the acid extract of the rind of citrus fruits or from apple pomace is used as a protectant and in cooking. Has a gelatinizing capacity and may be important in stabilizing the foam in frothy bloat.

  • p. methyl esterase a plant enzyme thought to have significance in the cause of bloat in cattle because of its role in the digestion of pectin and liberation of frothing agents pectic and galacturonic acids.

• pectinate [pek′tľ-nāt] comb-shaped.

  • imperforate p. ligament a cause of primary glaucoma; considered to be an inherited defect in a number of breeds of dogs. See also pectinate ligament dysplasia (below).
  • p. ligament the comb-like trabeculae spanning the iridocorneal angle and, deep to that, the trabecular meshwork.
  • p. ligament dysplasia goniodysgenesis; anomalous development of the pectinate ligaments such that they fail to rarefy and obstruct the iridocorneal angle. A major contributing factor to closed-angle glaucoma in veterinary species.
  • p. line see pectinate line.

• pectineal [pek-tin′e- l, pek″tľ-ne′ l] pertaining to the pectineus muscle. See pectinotomy.

• pectineus muscle see Table 12.4. See also pectinotomy.

• pectiniform [pek-tľ′ni-form] comb-shaped.

• pectinotomy [pek″t -not′ -me] surgical transection (myotomy) or removal (myectomy) of the pectineus muscle are procedures used to provide symptomatic improvement in the treatment of canine hip dysplasia.

• pectoral [pek′t r- l] 1. of or pertaining to the chest. 2. relieving disorders of the respiratory tract, as an expectorant.

  • p. girdle see pectoral girdle.
  • p. limb the forelimb.
  • p. muscles extrinsic muscles of the forelimb arising from the brisket (ventral chest). See also Table 12. Outbreaks of defective development of these muscles are recorded in cattle.
  • p. myopathy a meat hygiene term for the lesions found in turkey and meat chicken breasts causing rejection of the meat. Called also green muscle disease.

• pectoralis [pek″t -ra′lis] [L.] pertaining to the chest or breast; pectoral.

  P-23.

  

  Septic pedal interphalangeal arthritis

• pectus [L.] breast, chest, thorax.

  • p. carinatum a congenital deformity in which the sternum is angled caudoventrally and protrudes; less common than pectus excavatum (below). Called also pigeon breast.
  • p. excavatum a congenital deformity in which the caudal sternum is angled dorsally, protruding into the thoracic cavity thus compressing the heart and lungs.

• PED porcine epidemic diarrhea.

• pedal [ped′ l] pertaining to the foot or feet.

  • p. arthritis seen most often in cattle with septic arthritis of the distal interphalangeal joint.
  • p. bone the distal phalanx of ungulates, especially the horse where it is called also os ungulare or coffin bone or P3.
  • p. bone rotation ventral rotation of the distal phalanx often progressing to penetration of the sole of the horse’s foot; a characteristic of severe laminitis.
  • p. fracture fractures of the pedal bone occur most commonly in horses. There are multiple described fracture configurations in horses and may involve the body of the bone, a wing or the extensor process. They can be intra- or extra-articular. They are usually transverse in cattle.
  • p. osteitis a rarefying osteitis of the pedal bone in the foot of the horse. Causes local pain and lameness.

• pediatrics [pe″de-at′riks] a branch of human medicine that deals with the diseases of children; the name is also used in describing the medicine of young animals.

• pedicellation [ped″ľ-s -la′sh n] the development of a pedicle.

• Pedicinus a genus of sucking lice that infests monkeys. Members of the family Pediculidae. P. eurygaster (macques), P. mjobergi (howler monkeys), P. obtusus (leaf and green monkeys, and baboons), P. patas (colobus monkeys).

• pedicle [ped′ľ-k l] a footlike, stem-like, or narrow basal part or structure, such as a narrow strip by which a graft of tissue remains attached to the donor site.

  • p. advancement technique a surgical technique, commonly used in the repair of skin defects and defects in eyelids, in which a pedicle of tissue, usually skin, is formed and moved forward to fill a defect, without lateral movement. Various forms include the single or sliding flap, bipedicle flap, and V-Y technique. See also flap (1).
  • p. flap see pedicle graft.
  • omental p. flap a segment of omentum can be mobilized as a flap to aid in the reconstruction of the thoracic or body wall.
  • vertebral p. one of the paired parts of the vertebral arch that connect a lamina to the vertebral body.

• Pedicularis a genus of plants in the family Scrophulariaceae that contain digitalis-like alkaloids and glycosides that are potentially dangerous as poisons for animals. Called also louseworts.

• pediculation [p -dik″u-la′sh n] 1. the process of forming a pedicle. 2. infestation with lice.

• pediculectomy surgical removal of portions of vertebral pedicles at the level of the intervertebral foramen.

• pediculicide [p -dik′u-lľ-sīd] 1. destroying lice. 2. an agent that destroys lice.

• Pediculoides ventricosus the grain itch mite that infests cereal crops and stored hay and grain; parasitizes animals causing a mild dermatitis but a severe pruritus.

• pediculosis [p -dik″u-lo′sis] louse infestation.

• pediculous [p -dik′u-l s] infested with lice.

• pedigree [ped′ľ-gre] a table, chart, diagram, or list of an animal’s an-cestors, used in genetics in the analysis of mendelian inheritance, and in the prediction of productivity and breed quality in the offspring.

  • p. analysis a useful basis for planning a program to eliminate an inherited defect; the analysis determines the probability that each prospective parent is homozygous for the normal gene, i.e., is not a carrier for the anomaly gene; potential parents with a probability of >95% can be used with confidence.
  • p. herds herds or flocks composed of animals whose pedigrees are known. Not necessarily stud herds or registered herd but the terms are usually synonymous.
  • p. index the average of the predicted difference of the sire and the cow index of the dam. The pedigree index is allotted to the offspring.
  • p. selection use of an individual’s pedigree to select breeding animals.
  • p. verification verification via breed societies and production testing agencies, horse stud books, and race records are all used; checks via coat color, labiogram or nasal printing, DNA fingerprinting, and blood cell antigens may assist.

• ped(o)- word element. [L.] relationship to a foot or feet.

• pedogenesis [pe″do-jen′ -sis] production of offspring by a larval or immature stage of an organism; the individuals produced in an intermediate host of a parasite, e.g., the number of trematode cercariae produced in a snail following infection with a single miracidium; the number of protoscoleces of Echinococcus granulosus produced in an intermediate host (sheep) following the ingestion of a single egg.

• pedometer [p -dom′-t r] instrument strapped on a limb and used in dairy cattle to electronically record walking activity as a measure of the occurrence of estrus or lameness.

• peduncle [p -dung′k l] a stemlike connecting part, especially: (1) a collection of nerve fibers coursing between different regions in the central nervous system, or (2) the stalk by which a nonsessile tumor is attached to normal tissue.

  • cerebellar p’s three pairs of thick, white fiber trunks that arise from the midbrain, pons and medulla and pass into the cerebellum on either side of the fourth ventricle.
  • cerebral p. the ventral half of the midbrain, divisible into a dorsal part (tegmentum) and a ventral part (the paired crua cerebri), which are separated by the substantia nigra.
  • olfactory p. caudal continuation of the olfactory bulb of the brain.
  • pineal p. see habenula (2).

• peduncle disease historical name for coldwater disease.

• pedunculated [p -dung′ku-lāt- d] having a peduncle or stalk.

• pedunculus [p -dung′ku-l s] [L.] peduncle.

• PEEP positive-end-expiratory pressure. Used in respiratory therapy and anesthesia to maintain oxygenation in the presence of alveolar collapse (atelectasis).

• peer review evaluation of the merits of work produced by other scientists who work in the same field; includes papers submitted for publication, applications for research funding.

• pefloxacin a third-generation fluoroquinolone antibiotic with a broad range of activity against gram-negative and gram-positive bacteria, including anaerobes.

• peg [peg] a projecting structure; usually a small diameter, pointed piece of wood or metal, driven into a solid object.

  • rete p’s see rete pegs.
  • p. sticking see tent pegging.

• peg-leg osteomalacia. See phosphorus nutritional deficiency.

• Pega ass Brazilian roan or dark gray donkey.

• Peganum [peg′ -n m] a genus of plants in the family Zygophyllaceae. The plants contain β-carboline alkaloids, e.g., harmine, harmalol that cause incoordination and paralysis; includes P. harmala (African rue), P. mexicana (Mexican rue).

• pegleg see osteomalacia.

• PEG polyethylene glycol; percutaneous endoscopic gastrostomy.

• PEI pancreatic exocrine insufficiency.

• Peke-faced a longhaired Persian cat with a very short, flattened face, resembling that of a Pekingese dog.

• Pekin a deep-cream or buff- canary meat duck with bright orange legs, which also has a fair egg output.

• Pekingese a very small, compact dog with a large head, very short nose with undershot jaw, prominent eyes, and pendulous ears. The coat is long, straight, and profuse over the body, particularly around the neck where it forms a ‘mane’, and on the tail, which is carried over the back. Called also Peke, Foo dog, Lion dog. The breed is predisposed to distichiasis, hemivertebrae, intervertebral disc disease, proptosis, central corneal ulceration, facial fold pyoderma, and structural anomalies of the upper respiratory tract.

• pelada A Spanish term to describe a variety of llama characterized by low folicular density on the body and limited fiber growth on the extremities and face. Called k’ara or q’ara in Quechua. Compare to the wooly variety of llama, called lanuda or ch’aku (chaku).

• pelage [pel′ j] [Fr.] the hairy coat of mammals; the hairs, fur, or wool of the body, limb, and head, collectively.

• pelagic living in the middle or near the surface of large bodies of water such as lakes or oceans.

• Pelecitus roemeri filaroid nematode found in subcutaneous tissues, especially around the stifle joints, of wallabies and kangaroos. Formerly also Dirofilaria roemeri.

• Pelger-Huët anomaly [pel′g r] an inherited anomaly of neutrophils and eosinophils in which there is hyposegmentation of the nuclei. Seen rarely in dogs, cats, and Arabian horses with no clinical significance.

  • pseudo-P.-H. a. a transient hyposegmentation in neutrophils and eosinophils seen in cows with inflammation, occasionally in dogs and in cats with FeLV-induced myeloid leukemia. May be mistaken as the congenital anomaly.

  P-24.

  

  Band neutrophil (left) and neutrophilic myelocyte (right) in the blood of a dog with Pelger-Huët anomaly. Wright-Giemsa stain

• peliosis [pel″e-o′sis] purplish discoloration, usually due to vascular dilatation rather than hemorrhage.

  • p. hepatis irregular, blood-filled, cystic spaces in the liver.

• Pelistega europaea a gram-negative bacillus that causes respiratory disease in pigeons.

• pellagra [p -lag′r] a syndrome in humans caused by a diet seriously deficient in niacin (or by failure to convert tryptophan to niacin). In dogs called blacktongue. See also niacin nutritional deficiency.

  • feline p. ulcerative stomatitis, especially of the tongue, and conjunctivitis.

• pellagroid resembling pellagra.

• pellet [pel′ t] a small pill or granule.

  • p. feeding see pelleted feed.

• pellicle [pel′ľ-k l] 1. a thin scum forming on the surface of liquids. 2. a thin, nonliving outer covering.

  • dental p. a thin, acellular membrane of salivary proteins adsorbed to the enamel or cementum.

• pellucid [p -loo′sid] translucent.

• Pelodera a genus of nematodes in the family Rhabditida.

  • P. strongyloides a freeliving worm that invades broken skin, usually from damp and infected bedding. Causes pelodera dermatitis.

• pelt the undressed, raw skin of a wild animal with the fur in place. If from a sheep or goat there is a short growth of wool or mohair on the skin.

• pelves [pel′vēs] plural form of pelvis.

• pelvic [pel′vik] pertaining to the pelvis.

  • p. abscess most common in horses as a result of a rectal tear during a manual examination, or inadvertent penile entry during unsupervised breeding. The tear may only be mucosa deep, and the infection is deposited in the pelvic fascia where an abscess develops. This has the potential to erode into the peritoneal cavity. The syndrome begins as a toxemia and fever caused by the local abscess but a common sequel is the abrupt appearance of severe abdominal pain and toxemic shock. In some cases, the abscess may act as a space limiting structure and obstipation, or constipation may be the only clinical sign.
  • p. bone os coxae, comprising the ilium, ischium, and pubis. See also Table 9.
  • p. canal the canal from the pelvic inlet to the pelvic outlet.
  • p. cavity the space bounded by the bones of the pelvis.
  • p. diaphragm the muscular structure formed by the levator ani and coccygeous muscles, separating the perianal tissues from the peritoneum.
  • p. inlet the cranial opening of the pelvis.
  • p. intestinal hernia see pelvic hernia.
  • p. ligaments include the dorsal, ventral, and interosseous sacroiliac ligaments, the sacrotuberous and broad sacrotuberous ligaments, the sacrosciatic ligament, and the iliolumbar ligaments.
  • p. limb the hindlimb.
  • p. nerve see Table 13.
  • p. organs includes reproductive organs, urinary bladder, ureter, rectum.
  • p. outlet the caudal opening of the pelvis, guarded by the pelvic diaphragm.
  • p. plexus the autonomic plexus that is distributed to the pelvic viscera that consists of the cranial vesical plexus, the middle genital plexus and the caudal hemorrhoidal plexus, located on the ventrolateral surface of the rectum. It innervates the urinary bladder, prostate, ductus deferens and cranial urethra. It is supplied by the hypogastric and pelvic splanchnic nerves.
  • p. splanchnic nerves see nervi erigentes.
  • p. symphysiotomy surgical separation of the symphysis in immature animals as an aid in dystocia due to maternal pelvic inadequacy.
  • p. urethra that part of the urethra that passes through the pelvis.
  • p. viscera includes urinary bladder and pelvic ureters and urethra, rectum, prostate, vesicular glands (seminal vesicles), vas deferens, and ampullae in males, and vagina cervix and uterus, possibly ovaries, in the female.

• pelvicaliceal, pelvicalyceal pertaining to the renal pelves and calices.

• pelvicephalometry [pel″vľ-sef″ -lom′ -tre] measurement of the fetal head in relation to the maternal pelvis.

• pelvifixation [pel″vľ-fik-sa′sh n] surgical fixation of a displaced pelvic organ.

• pelvimeter [pel-vim′ -t r] an instrument for measuring the pelvis.

• pelvimetry [pel-vim′ -tre] measurement of the capacity and diameter of the pelvis, either internally or externally or both, with the hands or with a pelvimeter.

• pelviotomy [pel″ve-ot′ -me] 1. incision or transection of a pelvic (hip) bone. 2. pyelotomy; incision of the renal pelvis.

• pelviperitonitis [pel″ve-per″ľ-to-ni′tis] inflammation of the pelvic peritoneum.

• pelvirectal [pel″vľ-rek′t l] pertaining to the pelvis and rectum.

• pelvis [pel′vis] pl. pelves the caudal portion of the trunk of the body, forming a basin. The ring of bone formed by the sacrum and the first few coccygeal vertebrae as the roof, the pubis, and ischia as the floor and the ilia and the acetabular part of the ischia as the walls. Bounded ventrally and laterally by the hip bones and dorsally by the sacrum and coccygeal vertebrae. Also applied to any basin-like structure, e.g., the renal pelvis.

  • android p. a type of pelvis typically found in the male. It is less easy to distinguish the sexes of domestic animal pelves than it is in humans.
  • extrarenal p. see renal pelvis (below).
  • rachitic p. one distorted as a result of rickets.
  • renal p. the funnel-shaped expansion of the cranial end of the ureter; it is usually within the renal sinus, but under certain conditions, a large part of it may be outside the kidney (extrarenal pelvis).
  • split p. one with a congenital separation at the symphysis pubis.
  • tipped p. a tilted pelvis as occurs in cows and causes the external urinary meatus to be higher than the anterior pelvic floor so that urine accumulates in the vagina. See also urovagina.

• pelviureteral [pel″ve-u-re′t r- l] relating to the renal pelvis and the ureter.

• pelvospondylitis [pel″vo-spon″d -li′tis] inflammation of the pelvic por-tion of the spine.

• Pembroke Welsh corgi see Welsh corgi.

• pemoline [pem′o-lēn] a central nervous system stimulant; sometimes used to treat narcolepsy, it is no longer available in the US.

• pemphigoid [pem′fľ-goid] 1. resembling pemphigus. 2. a group of skin disorders similar to but clearly distinguishable from pemphigus.

  • bullous p. an immune-mediated disease of skin and oral mucosa in which autoantibodies are formed against adhesion molecules of the epidermaldermal junction. The inflammatory response results in subepidermal cleft formation with vesicles and bullae leading to deep ulcerations, mainly in the oral cavity, on lips and pinna. Even minor trauma causes lesions. Occurs rarely in dogs, cats, and humans.

• pemphigus [pem′fľ-g s] [Gr.] pemphix (blister); a group of uncommon immune-mediated diseases of the skin and mucous membranes caused by autoantibodies targeting adhesion molecules within the epidermis andcharacterized histologically by acantholysis and clinically by vesicles, bullae, erosions, and ulcerations; occurs in dogs, cats, goats, and horses. Different forms are distinguished by the different adhesion molecules targeted. The major subsets are pemphigus foliaceus and pemphigus vulgaris; rare variants are pemphigus vegetans, paraneoplastic pemphigus, and pemphigus erythematosus. Drug reactions may also be a cause. See also desmogleins.

  P-25.

  

  Pelodera dermatitis

  P-26.

  

  Hyperkeratosis of the footpads in a dog with pemphigus foliaceous

  • p. erythematosus a form with features of both pemphigus foliaceus and lupus erythematosus; occurs in dogs and cats. There are erythematous, pustular lesions, mainly on the nose, periorbital skin and pinnae, and hypopigmentation of the planum nasale. Believed to be exacerbated by exposure to light; occurs most often in Collies where it is one of the diseases called ‘collie nose’.
  • p. foliaceus results from autoantibodies directed against the desmosomal antigen, desmoglein I, found in the superficial layers of the epidermis, paw pad, and nasal planum. There are pustular, sometimes preceded by papular, eruptions that rupture, leaving a scaling disease, which may be generalized or limited to the face, ears, nasal planum. Pruritus is variable, and there may be systemic signs of illness. Horses present multifocal to generalized crusting, scaling, and alopecia, occasionally painful and/or pruritic, affecting the face, neck, trunk, and extremities. Rare in goats, it results in pustules, crusts, scales, and alopecia, which predominate on the face, ventral abdomen, limbs, perineum, and tail.
  • paraneoplastic p. a rare and severe form of pemphigus associated with neoplasia at some site in the body; characterized by suprabasilar clefting and autoantibodies to periplakin and envoplakin.
  • p. vegetans a rare variant of pemphigus vulgaris in which the bullae are replaced by verrucoid hypertrophic vegetative masses.
  • p. vulgaris an acute and severe form of pemphigus caused by autoantibodies directed against the desmosomal antigen, desmoglein 3, found in the basal levels of the epidermis and mucous membranes. There are vesicobullous eruptions followed by deep ulcerations and crusting, predominantly at mucocutaneous junctions and on oral mucosa; involvement of footpads and nail beds with loss of nails also occurs.

• pen 1. a small enclosure in which animals are housed. 2. female swan.

  P-27.

  

  Erosive dermatitis on the footpads of a dog with pemphigus vulgaris

  • add-on p. in a feedlot, one in which cattle are put together a few head at a time over several days or weeks. Has a risk for health problems.
  • calf rearing p. pens in which dairy calves are reared from birth until they are weaned off milk, commonly around 2 months of age, when they are eating sufficient solid food. The pens are located communally in an area of the dairy. Calves are usually reared in separate pens until weaned when they are penned in groups. Also called simply calf pens, calf hutch.
  • p. check the daily or twice daily examination of cattle in a feedlot to detect any sick animal. More frequent checks are made in the early period of a feeding program.
  • p. checker the specially selected cowboys whose task it is to carry out intensive pen checks.
  • crowding p. situated at the entry to the milking shed. Pen can continually be made smaller so that the entry of cows into the milking parlor is facilitated. Called also push pen.
  • p. deads feedlot term for cattle found dead in the pen as opposed to being found dead in the hospital pen. Suggest inadequate observation of the cattle.
  • p. design includes materials for floor and walls, floor drainage and warmth, disposal of feces and urine, sleep area versus feeding area, troughage and drinking facilities, space and number of occupants proposed.
  • pen-fed fed in small, compatible groups in pens to optimize feed utilization.
  • holding p. a pen, paddock, or yard for holding a group of sheep or cattle temporarily, e.g., before slaughter, after shearing. A pen to which animals are added one by one until a group of sufficient size is accumulated.
  • maternity p. accommodation provided to encourage the establishment of the maternal–neonatal bond, to maximize the chances of survival of both and the return to a breeding status for the dam, and a good start for the growth period in the young animal. Includes maternity box stall, maternity barn.
  • push p. see crowding pen (above).
  • p. space space allocation per head of livestock proposed to be accommodated.
  • p. sweeps wool swept up from pens, shearing board, races.
  • wash p. a corral or pen with a solid floor and permanent sprinklers or other washing devices that jet upwards for cleaning cows collectively prior to milking. Usually associated with a holding pen.

• Penaeus genus of farmed crustaceans in suborder Penaeidae; includes P. chinensis (fleshy or white prawn), P. indicus (Indian white prawn), P. monodon (giant tiger prawn), P. vannamei (whiteleg shrimp), P. merguiensis (banana prawn), P. vannamei (whiteleg shrimp).

• pencil bush Eremophiladeserti.

• pencil caustic Sarcostemmaaustrale.

• pendulous [pen′du-l s] hanging loosely; dependent.

• penectomy [pe-nek′t -me] surgical removal of the penis.

• penetrance [pen′ -tr ns] the frequency with which a particular gene or set of genes is expressed as a phenotype. Called also genetic penetrance.

  • incomplete p. when penetrance is less than 100%.

• penetrating [pen′ -trāt-ing] breaching the tissues of the body.

• penguin completely marine, aquatic flightless bird inhabiting only the southern hemisphere, of the family Spheniscidae. There are six genera, all of them gregarious, monogamous, and piscivorous. Includes King penguin (Aptenodytes patagonicus), Emperor penguin (A. forsteri), Crested penguin (Eudyptes spp.), Fairy penguin (Eudyptula spp.), and Adelie penguin (Pygoscelis adeliae).

  • -penia word element. [Gr.] deficiency.

• penicillamine [pen″ľ-sil′ -mēn] a product of penicillin that chelates copper and other metals; used in the treatment of copper-storage disease and lead poisoning. Called also D-penicillamine.

• penicillic acid [pen″ľ-sil′ik] a mycotoxin with antibiotic and carcinogenic acivity produced by various species of Penicillium and Aspergillus.

• penicillin [pen″ľ-sil′in] any of a large group of natural or semisynthetic antibacterial drugs derived directly or indirectly from strains of fungi of the genus Penicillium and other soil-inhabiting fungi grown on special culture media. Penicillins exert a bactericidal or bacteriostatic effect on susceptible bacteria by interfering with the final stages of peptidoglycan synthesis, a component of the bacterial cell wall. Despite their relatively low toxicity for the host, penicillins are active against many bacteria, especially gram-positive pathogens such as streptococci, some staphylococci and clostridia, as well as certain gram-negative bacteria, spirochetes (Treponema pallidum and T. pertenue), and fungi. Certain strains of some target species, for example, staphylococci, secrete the enzyme penicillinase, which inactivates penicillin and confers resistance to the antibiotic. Some of the staphylococcal penicillins, for example, methicillin, are more effective against penicillinase-producing organisms. An additional class of extended-spectrum penicillins has been approved for use; it includes piperacillin, ticarcillin, and mezlocillin. Penicillins are time-dependent antibiotics; they exert their optimal bactericidal effect when drug concentrations are maintained above the minimum inhibitory concentration (MIC) for the pathogen. A typical target is to maintain drug concentrations 2–4 times the MIC throughout the dosing interval. Unlike the concentration-dependent antibiotics, higher concentrations do not result in greater bactericidal activity, and there is little or no postantibiotic effect (PAE). There are four groups of penicillins: (1) the natural penicillins, penicillin G and penicillin V, have a relatively narrow spectrum of activity, mainly against gram-positive bacteria; (2) the aminopenicillins, including amoxicillin, ampicillin, and hetacillin, are semisynthetic derivatives that have a broad spectrum of activity against gram-positive and many gram-negative organisms, but are susceptible to penicillinase; (3) penicillinase-resistant penicillins, which include cloxacillin, methicillin, nafcillin, and oxacillin; and (4) the extended-spectrum penicillins (azlocillin, carbenicillin, mezlocillin, piperacillin, and ticarcillin), which are effective against gram-positive and gram-negative organisms (aerobes and anaerobes), including Pseudomonas aeruginosa. Allergic reaction to penicillin occurs with repeated exposure in some animals and ranges from urticaria to anaphylaxis, which may be fatal. (An acute systemic response, notably hyperactivity or panic, following inadvertent intravascular injection of procaine penicillin G in horses may occur with the first dose and is caused by procaine toxicity rather than penicillin allergy.)

  • p. allergy degradation products of the penicillins act as haptens, binding to proteins and stimulating an immune response.
  • p. G benzylpenicillin; the most widely used penicillin; used principally in the treatment of infections caused by gram-positive bacteria. Procaine penicillin G is a parenteral preparation—only for intra-muscular injection—that can maintain therapeutic concentrations for 12–24 hours; benzathine penicillin G is a very slow-release, parenteral preparation that maintains blood concentrations for several days but may not achieve therapeutic concentrations (2–4 times MIC for target pathogens) so it is best suited for prophylactic antibiotic therapy in relatively low-risk situations.
  • p.-induced hemolytic anemia rare problem in horses that develop IgG anti-penicillin antibodies.

• phenoxymethyl p. a biosynthetically or semisynthetically produced antibiotic, similar to penicillin G; not affected by gastric acid so it is suitable for oral administration. Its antibacterial spectrum is the same as for penicillin G. Called also penicillin V.

  • p. V see phenoxymethyl penicillin (above).

• penicillinase [pen″ľ-sil′ľ-nās] an enzyme produced by bacteria that inactivates penicillin by hydrolyzing the beta-lactam ring, thus increasing resistance to the antibiotic; a purified form from Bacillus cereus is used in the treatment of reactions to penicillin.

• penicilliosis [pen′ľ-sil″e-o′sis] infection by the blue-green mold, Penicillium; causes a necrotic rhinitis and sinusitis that occasionally extends to the mouth or orbit. The disease is similar to aspergillosis.

• Penicillium [pen″ľ-sil′e- m] a genus of mold-forming fungi in the phylum Ascomycota that grow on stored feed and in growing plants. Some produce antibiotics, some can be opportunistic pathogens and some produce mycotoxins, including patulin.

  • P. chrysogenum, P. notatum cultures of these fungi produce penicillin. Now regarded as a single species, P. chrysogenum.
  • P. citreo-viride produces the neurotoxin citreoviridin that causes paralysis, convulsions, and death in humans eating contaminated yellow rice. Resembles beriberi, thought originally to be due to thiamine deficiency.
  • P. citrinum produces ochratoxin, citrinin, causes growth retardation, hepatic necrosis, and nephropathy.
  • P. claviforme, P. cyclopium, P. divergens, P. equinum, P. expansum, P. griseofulvum, P. lapidosum, P. leucopus, P.melinii, P. novae-zeelandiae, P. patulum (syn. P. urticae) produce the antibiotic patulin.
  • P. crustosum produces tremorgens that cause incoordination and recumbency and was thought at one time to cause ryegrass staggers.
  • P. cyclopium, P. janthinellum, P. nigricans (syn. P. janczewskii), P. palitans, P. piscarum, P. puberulum are soil fungi and produce tremorgens that cause tremor, ataxia, and muscular rigidity in animals grazing infested pasture. The fungi were once thought to be involved in causing ryegrass staggers.
  • P. estinogenum produces tremorgens and causes incoordination and recumbency.
  • P. islandicum causes hepatic necrosis and has carcinogenic properties.
  • P. purpurogenum produces rubratoxin and causes anemia and widespread hemorrhages in chickens.
  • P. roqueforti grows on stored grain and ensilage; suspected of causing bovine abortion and retained placenta via an unidentified toxin. Produces roquefortine that causes tetanic convulsions in dogs.
  • P. rubrum contains rubratoxin that causes abdominal pain, jaundice, convulsions. Now classified as P. purpurogenum.
  • P. simplicissimus fungus that produces tremorgens, causing incoordination and recumbency.
  • P. viridicatum grows on stored grain and produces ochratoxin that causes nephrosis mostly in pigs. Also produces citrinin and viomellin.

• penicilloyl-polylysine [pen″ľ-sil′o- l pol″e-li′sēn] a diagnostic agent prepared from polylysine and a penicillic acid; intradermal reaction elicits a wheal and erythema response in patients sensitive to penicillin.

• penicillus [pen″ľ-sil′ s] pl. penicilli [L.] brushlike in appearance; e.g., groups of arterial branches in the lobules of the spleen.

• penile [pe′nīl] of or pertaining to the penis.

  • p. abscess usually secondary to penile hematoma, causes apparent swelling of the ventral body line of affected bulls. The lesions are moderately painful to touch, are firm and hard and persist for long periods. Associated adhesions make it impossible for the bull to extrude the penis.
  • p. amputation carried out in horses for treatment of extensive neoplasms and granulomas and for paralysis of the penis. Called also phallectomy.
  • p. apical ligament a fibrous band along the dorsal surface of the distal part of the penis of the bull which helps to produce a slight twist (with a left-hand spiral) in the erect state. Abnormality may contribute to the development of deviation of the penis during erection.
  • p. bulb a swelling at the origin of the corpus spongiosum penis. Distinguish from bulbus glandis, or bulb of the glans of the penis.
  • p. crura the origins of the corpus cavernosum penis at the ischial arch.
  • p. deviation a common defect only in bulls in which an abnormality of the apical ligament, present congenitally or caused by trauma, causes a spiral, lateral or ventral deviation of the penis, causing difficulty in mating. See also penile translocation (below), corkscrew penis.
  • p. erection see erection.
  • p. eversion see penile prolapse.
  • p. frenulum see penile preputial frenulum.
  • p. glans see glans penis.
  • p. hair-ring long hairs from the preputial orifice pack up around the penis of the bull and cause pressure necrosis occasionally creating a hypospadias. Can occur in any species carrying preputial hairs.
  • p. hematoma in bulls, in which it is a common event, it is caused by trauma while the bull is mating a cow resulting in rupture of the penile tunica albuginea of the corpus cavernosum and local hemorrhage. It occurs typically laterally or dorso-laterally at the level of implantation of the retractor penis muscle, distal to the distal curve of the sigmoid flexure, resulting in an obvious swelling and an inability to breed cows.
  • p. hypoplasia occurs as a congenital anomaly, as part of an intersex deformity, or as a sequel to prepubertal castration.
  • inadequate p. protrusion due to congenital shortness of the penis, adhesions caused by injury and hematoma, and persistence of the penile frenulum.
  • p. ossification a radiological finding in aged dogs; ossification caudal to os penis.
  • p. paralysis common only in stallions, due to local neurological lesion, or as a rare occurrence after the administration of phenothiazine-derived tranquilizers or severe debility.
  • persistent p. frenulum see penile preputial frenulum.
  • p. protrusion failure caused by persistent frenulum, adhesions to prepuce, fibropapilloma.
  • p. sigmoid flexure the S-shaped bend in the penis of ruminants, camelids, and pigs; effacement of this flexure is the principal means of creating an elongation of the penis during erection; the subsequent detumescence of the penis brings about a return of the S-shape and retraction of the now flaccid organ to its resting position in these species. See Table 12.2 retractor penis.
  • p. tiedown an adhesion of the penis to the prepuce created artificially to prepare the animal as a teaser.
  • p. translocation surgical procedure to prepare teaser bulls or rams; the prepuce and its orifice are displaced laterally in order to eliminate any chance of copulation.
  • p. tunica albuginea the dense connective tissue covering of the corpus cavernosum penis.

• penis [pe′nis] the external male organ of urination and copulation. Its structure varies a great deal between the species. In carnivores and horses, the bulk of the organ is erectile tissue (cavernous penis); in cats and dogs, there is a bone included in the glans. In cats, the penis is directed backward (retromingent). In ruminants and pigs, the bulk of the penis is connective tissue (fibroelastic penis), and the organ is long and firm and has a large sigmoid flexure that disappears when the penis is in the erect state. In rams and goat bucks, the penile urethra is continued beyond the glans as the urethral process. See also penile.

  • broken p. see penile hematoma.
  • corkscrew p. see corkscrew penis.
  • corpus cavernosum p. one of the two bodies that make up the dorsal compartment of erectile tissue of the penis, grooved below to carry the corpus spongiosum penis (syn. corpus cavernosum urethrae). It arises from each side of the ischial arch as the crus penis and at its anterior end is enclosed by the glans, which is an extension of the corpus spongiosum; in many species, the two bodies fuse in the midline, and in carnivores, the bodies are continued cranially as an os penis that supports the surrounding glans penis.
  • corpus spongiosum p. a column of erectile tissue around the urethra of the penis and extending into the glans penis.
  • double p. diphallus.
  • short p. an uncommon, possibly inherited, defect in some breeds of cattle.
  • supernumerary p. a rare deformity, usually ectopic.
  • p. urethral process detached the free end of the penis has a bifid structure.

• penitis [pe-ni′tis] inflammation of the penis. See also balanitis.

• penitrem-A a indole-diterpenoid tremorgen produced by several terrestrial and few marine Penicillium species, but primarily P. crustosum. A potent tremorgen causing nervous signs and renal damage. Intoxication characterized by tremors and seizures is recorded in dogs consuming moldy human food.

• Penn State particle separator stacked series of sieves with different aperture sizes used to determine the particle size distribution in total mixed rations.

• PennHIP a radiographic screening method for measuring hip joint laxity in dogs; requires a series of different projections of the hips taken by veterinarians specially trained in the methodology. See also distraction index.

• penniform [pen′ľ-form] shaped like a feather.

• Pennisetum a genus of grasses in the family Poaceae.

  • P. americanum a large grass used as a fodder crop. Can be poisonous if infested with the fungus Claviceps fusiformis, known to cause agalactia in sows. Called P. glaucum, also bulrush, Indian, horse, or pearl millet.
  • P. ciliare a grass of the family Poaceae; called also Cenchrus ciliaris, buffel grass. Grazing of pure or near-pure swards of this pasture plant by horses can cause nutritional secondary hyperparathyroidism because most of the calcium in the grass is in the form of oxalate crystals and unavailable for absorption. In very lush pasture, it can cause acute oxalate poisoning in sheep and cattle, but only if they are very hungry.
  • P. clandestinum perennial, creeping grass with hairy leaves and inconspicuous flowers. Has a rapid summer growth period; suitable for green chop, silage or grazing. May have a low fiber content and cause depression of fat content of milk. A very valuable grass producing an enormous bulk of feed in suitable climates. It can be poisonous, causing so-called kikuyu poisoning of cattle, a high case-fatality ratio syndrome of salivation, dehydration, sham drinking, ruminal distention and stasis, staggering and a high-stepping gait, kidney dysfunction, rumen microvesication, and nephrosis. Various causes have been suggested, the currently most promising being wortmannin, a viridian-like furanosteroid mycotoxin produced by Fusarium torulosum. Trichothecene mycotoxins from Myrothecium spp. and Phoma herbarum growing on plant debris after a period of lush growth or infestation with army caterpillars is unlikely as the cause. P. clandestinum can also cause oxalate and nitrite poisoning. Called also Kikuyu grass.
  • P. glaucum see Pennisetum americanum (above).
  • P. polystachyonP. purpureum. Called also mission grass.
  • P. purpureum its oxalate content is known and is associated with the occurrence of nutritional secondary hyperparathyroidism in horses. Called also elephant or Napier grass.
  • P. typhoides see Pennisetum americanum (above).

• penny-cress see Thlaspi arvense.

• pennyroyal [pen″e-roi′ l] Mentha pulegium.

  • p. oil an aromatic extract of several mint plants, particularly Mentha pulegium and M. canadensis. Sometimes used as an insecticide or insect repellent on dogs and cats, but can be a cause of hepatotoxicosis, particularly in cats.

• Penrose drain see Penrose drain.

• Penstemon a North American genus of plants in the family Scrophulariaceae which act as facultative selenium converters; the selenocompounds produced by the plant cause alopecia, lameness, laminitis; called also beard tongue.

• pent(a)- word element. [Gr.] five.

• pentachloronaphthalene see chlorinated naphthalenes.

• pentachloronitrobenzene (PCNB) a soil fungicide used extensively in agricultural crops and not known to cause illness, but it is of environmental concern because of its capacity to enter the human food chain and cause tissue residues in all species.

• pentachlorophenol (PCP) [pen″t -klo″ro-fen′ol] principal use is as a wood preservative but also an insecticide and herbicide. Has great capacity to enter the body by any route, including percutaneously; causes weight loss, low milk production, and general debility. PCP can uncouple oxidative phosphorylation in exposed animals, leading to hyperthermia, tremors, and seizures. Now a restricted use chemical in most countries

• pentadactyl [pen″t -dak′t l] having five digits.

• pentadiene isomers compounds used as preemergence herbicides; can cause excitability, incoordination, and prostration.

• pentagastrin a synthetic pentapeptide consisting of β-alanine and C-terminal tetrapeptide of gastrin; once used in a test of gastric secretory function.

• Pentalinon luteum Central American plant in the family Apocynaceae; causes sudden death, generalized haemorrhage, and cardiomyopathy in cattle. Called also Urechites lutea, bejuco marrullero, wild allamanda, yellow nightshade.

• pentamer [pen′t -m r] a polymer formed from five molecules of a monomer.

• pentamidine isethionate [pen-tam′ľ-dēn] a diamidine derivative effective against protozoa. Used in the treatment of Babesia, Leishmania, and Pneumocystis spp.

• pentaploidy [pen′t -ploi″de] the state of having five sets of chromosomes (5n).

• pentasomy [pen″t -so′me] a type of polysomy characterized by the presence of three additional chromosomes of one type in an otherwise diploid cell (2n + 3) (e.g. pentasomy X).

• pentastome [pen′t -stōm] arthropod parasite belonging to the class Pentastomida. Currently claasified as Crustacea. Includes Linguatula, Porocephalus, and Armillifer spp. Usually found in the respiratory system of birds, mammals, and reptiles.

• pentastomiasis [pen″t -sto-mi′ -sis] infection by parasites of the class Pentastomida; found in the respiratory tract of reptiles, mammals, or birds.

• Pentastomida [pen″t -sto′mid-] see pentastome.

• pentastomidiasis [pen″t -sto-mid′i-ā-sis] infection with pentastomes.

• Pentatrichomonas [pen″t -trik″o-mo′n s] a genus of protozoan parasites with five flagella.

  • P. hominis (syn. Trichomonas hominis, T. intestinalis) found in dogs, primates, and humans but appears to be nonpathogenic.

• pentavalent [pen″t -va′l nt] having a valence of five.

  • p. antimony compounds see antimony.
  • p. organic arsenicals includes the pharmaceuticals arsanilic acid, roxarsone, nitarsone. See also organic arsenical.

• pentazocine lactate [pen-taz′o-sēn] a synthetic narcotic agonist (kappa and sigma) /antagonist (mu) used as an analgesic.

• pentetic acid [pen-tet′ik] diethylenetriamine penta-acetic acid, an ironchelating agent.

• pentobarbital [pen″to-bahr′bľ-t l] a short- to intermediate-acting barbiturate; used as a hypnotic and sedative in the form of the sodium salt. Overdoses are administered for euthanasia of animals.

• pentobarbitone [pen″to-bahr′bľ-tōn] British name for pentobarbital.

• pentosan polysulfate [pen′to-san] a polysulfated xylan used in the treatment of osteoarthritis and also in feline lower urinary tract disease.

• pentosans pentose polysaccharides found in fruits and other foods; form pentoses on hydrolysis.

• pentose a monosaccharide containing five carbon atoms in a molecule.

  • p. cycle see pentose phosphate pathway (below).
  • p. phosphate pathway called also pentose cycle; see pentose phosphate pathway.

• pentoside [pen′to-sīd] a compound (glycoside) of pentose with another substance.

• pentosuria [pen″to-su′re- ] high concentration of pentose in the urine.

• pentoxifylline [pen″tok-sif′ -lin] a methylxanthine derivative that causes an increase in microvascular blood flow and has an immunomodulating effect by suppression of proinflammatory cytokines. Used in the treatment of some canine skin diseases, especially vasculitis and dermatomyositis.

• pentylenetetrazol see leptazol.

• penumbra [p -num′br] a blurred edge to an image, a halo effect, in an xray film caused usually by an overlarge focal spot exacerbated by a long object-to-film distance.

• People for the Ethical Treatment of Animals (PETA) an activist animal rights group that is active in garnering political and public support and funding against the mistreatment of animals. It is considered a radical organization by some, and its goal is that animals are not available to humans for food, clothing, entertainment, or medical advancement.

• People’s Dispensary for Sick Animals a charitable organization providing free veterinary care to sick and injured animals in the UK. A branch, now autonomous, with the same name is located in South Africa

• PEP phosphoenolpyruvate.

• PEP-CK phosphoenolpyruvate-carboxykinase.

• peplomer [pep′lo-m r] a glycoprotein structural unit found in the lipoprotein envelope of enveloped viruses, e.g., H and N spikes of influenza virus. Called also spikes.

• peplos [pep′lōs] the outer lipoprotein coat of enveloped viruses.

• pepperina Schinusmolle.

• Peppin famous strain of Australian Merino sheep.

• pepsin [pep′sin] a proteolytic enzyme that is the principal digestive component of gastric juice. It acts as a catalyzt in the chemical breakdown of protein to form a mixture of polypeptides; it is formed from pepsinogen in the presence of acid or, autocatalytically, in the presence of pepsin itself. Pepsin also has milk-clotting action similar to that of rennin and thereby facilitates the digestion of milk protein.

  • p. barrier the gastric mucosal mechanism that prevents rediffusion of hydrochloric acid back into gastric tissues; includes an electrical resistance, mucus, plus bicarbonate ions trapped in the mucus, endogenous prostaglandins.

• pepsinogen [pep-sin′ -j n] a zymogen secreted by the chief cells of the gastric glands and converted into pepsin in the presence of gastric acid or of pepsin itself.

• plasma p. high concentrations are indicative of extensive mucosal damage in the abomasum, as in ostertagiasis in ruminants.

• peptic [pep′tik] pertaining to pepsin or to digestion or to the action of gastric juices.

  • p. ulcer an ulceration of the mucous membrane of the esophagus, stomach or duodenum, caused by the action of the acid gastric juice. There are two kinds of peptic ulcers: gastric ulcers occur in the stomach; duodenal ulcers occur in the duodenum, the part of the small intestine nearest the stomach. See also Zollinger-Ellison syndrome.

• peptidase [pep′tľ-dās] any of a subclass of proteolytic enzymes that catalyze the hydrolysis of peptide linkages.

• peptide [pep′tīd] any of a class of compounds of low molecular weight that yield two or more amino acids on hydrolysis; known as di-, tri-, tetraetc., peptides, depending on the number of amino acids in the molecule. Peptides form the constituent parts of proteins. See also polypeptide.

  • leader p. peptide coded for by a leader sequence in the regulation of transcription by attenuation in bacteria.
  • p. map a pattern of peptide fragments, characteristic of a particular protein. Produced by using either proteolytic enzymes such as trypsin or chemicals such as cyanogen bromide to cut proteins at a relatively small number of particular sites, the peptide fragments are then separated by chromatographic or electrophoretic procedures. Called also fingerprint.
  • p.-para-aminobenzoic acid test see BT-PABA test.
  • signal p. see signal sequence.

• peptidergic [pep″tľ-dur′jīk] of or pertaining to neurons that secrete peptide hormones.

  • p. neurons a group of enteric interneurons that contain peptides; the peptides include enkephalins and somatostatins.

• peptidoglycan [pep″tľ-do-gli′k n] a glycan (polysaccharide) attached to short cross-linked peptides; found in bacterial cell walls and responsible for their structural rigidity.

• peptidolytic [pep″tľ-do-lit′ik] capable of splitting up peptide bonds.

• peptidoma see apudoma.

• peptidyl site see peptidyl-tRNA binding site.

• Peptococcus [pep″to-kok′ s] a genus of non–spore-forming, gram-positive anaerobic cocci that have been recovered from infected dog bite wounds. The type species is P. niger.

• peptogenic [pep″to-jen′ik] 1. producing pepsin or peptones. 2. promoting digestion.

• peptolysis [pep-tol′ľ-sis] the splitting up of peptone.

• peptone [pep′tōn] protein derivative formed by partial hydrolysis of a protein.

• Peptoniphilus indolicus [pep″to-nľ-phil′ s] a coccoid gram-positive anaerobic bacterium implicated in the etiology of mastitis in cattle, especially in summer mastitis. Previously called Peptostreptococcus indolicus.

• Peptostreptococcus [pep″to-strep″to-kok′ s] gram-positive round or oval bacteria occurring singly or in long chains. Found as an normal flora in many species and humans.

  • P. anaerobius isolated from abscesses in dogs and cats.
  • P. heliotrinreducens now called Slackia heliotrinireducens.
  • P. indolicus implicated in the etiology of mastitis in cattle, especially in summer mastitis. Now called Peptoniphilus indolicus.

• per- word element. [L.] 1. throughout, completely, extremely. 2. in chemistry, a large amount, combination of an element in its highest valency.

• per anum [p r a′n m] [L.] through the anus.

• per cloaca [p r klo-ā′k] administration of a product via the cloaca, typical fluid or drugs.

• per oral peroral, through the mouth; as a directive, most often written per os.

• per os [L.] by mouth.

• per primam [L.] by first intention; see also healing.

• per rectum [L.] by way of the rectum.

• per secundam [L.] by second intention; see also healing.

• per tertiam [L.] by third intention; see also healing.

• per tubam [L.] through a tube.

• per vaginam [L.] through the vagina.

• peracetic acid [per″ -se′tik] a potent disinfectant used as a 3% concentration; suitable for the destruction of anthrax spores.

• peracid [per-as′id] an acid containing an -OOH group. Also called peroxy acid.

• peracute [per″ -kūt′] very acute; a duration of a few hours only.

• peramine metabolite of the fungus Epichloë (Neotyphodium, Acremonium) lolii; repellent to insects.

• Perca a genus of freshwater fish in the family Percidae; includes perch and pike-perch.

  • P. pluviatilis European freshwater fish species used extensively as food; introduced into many countries. Variously regarded as a valuable sports species or as a pest. Called also redfin perch.

• Percavirus a genus in the subfamily Gammaherpesvirinae that contains Equid herpesvirus 2, Equid herpesvirus 5, and Mustelid herpesvirus 1.

• percentile [p r-sen′tīl] 1. one of 100 equal parts of a series of mea-surements, each group being of equal size, and arranged in order of their magnitude; the 20th percentile is the value in the series below which 20% of the values fall. 2. the dividing points between such groups.

• perception [p r-sep′sh n] the conscious mental registration of a sensory stimulus. The ability of animals to perceive is apparent from their responses to the application of stimuli but the nature of the perceptivity is only surmised. The difficulty in examining an animal is to decide whether a failure to respond to a stimulus is due to lack of perception, inability to respond or disinclination to do so.

• perch common name given to fish in the genus Perca. Examples of species in this genus include yellow perch and European perch. Sometimes the name is used for fish in other genera as well (i.e., giant sea perch is used to describe barramundi)

  • giant sea p. see Lates calcarifer.
  • redfin p. see P. pluviatilis.

• Percheron a French heavy draft horse, of graceful build and action. Gray, white, or black, 15.2–17 hands high.

• perching characteristic resting posture of birds, for example, on branches; facilitated by anatomical arrangement of the digital flexor tendons—when the bird squats the knee and hock joints are flexed and the digital tendons flex passively, the digits grasping the perch.

• perchlorate ion one of the competing ions that blocks the uptake and transport of iodine ions.

• percolate [pur′ko-lāt] 1. to undergo percolation. 2. a liquid that has been submitted to percolation. 3. to trickle slowly through a substance.

• percolation [pur″k -la′sh n] the extraction of soluble parts of a substance by passing a solvent liquid through it.

• percuss [p r-kus′] to perform percussion.

• percussible [p r-kus′ľ-b l] detectable on percussion.

• percussion [p r-kŭ′sh n] in veterinary diagnosis, striking a part of the body with short, sharp blows of the fingers in order to determine the size, position, and density of the underlying parts by the sound obtained. Percussion is most commonly used on the chest and back for examination of the heart and lungs. For example, since the heart is not resonant and the adjacent lungs are, when the examiner’s fingers strike the chest over the heart the sound waves will change in pitch. This serves as a guide to the precise location and size of the heart. The value of percussion in animals is limited by their haircoat, their reluctance to cooperate, and their anatomy. Radiology and ultrasonographic imaging have pretty much supplanted the percussionist.

  P-28.

  

  Percheron horse

  • auscultatory p. auscultation of the sound produced by percussion. See also auscultation with percussion.
  • immediate p. that in which the blow is struck directly against the body surface.
  • mediate p. that in which a pleximeter is used.
  • palpatory p. a combination of palpation and percussion, affording tactile rather than auditory impressions. See also ballottement.
  • p. therapy see coupage.

• percussor [p r-kus′ r] an instrument for performing percussion.

• percutaneous [pur″ku-ta′ne- s] performed through the skin, e.g., percutaneous cystocentesis.

• Père David’s deer (Elaphurus davidianus) a Chinese deer; apart from small populations reintroduced into the wild, found only in zoos or park reserves. It has a long tail and branched antlers. Also known as the milu or elaphure.

• perencephaly [per″ n-sef′ -le] porencephaly.

• Perendale a dual-purpose, polled, New Zealand sheep, produced by crossing the Romney Marsh and Cheviot breeds; wool 28–32 microns. It has a head clear of wool and a profile and stance like the Cheviot.

• perennial [p -ren′e- l] a plant with a life cycle of more than one year.

• perfect state [pur′f kt] the sexual stage in the life cycle of fungi.

• perfloxacin pefloxacin.

• perforans [pur′f -ranz] [L.] penetrating; a term applied to various muscles and nerves.

• perforating canals canals in bone through which blood vessels pass.

• perforation [pur″f -ra′sh n] a hole or break in the containing walls or membranes of an organ or structure of the body. Perforation occurs when erosion, infection, or other factors create a weak spot in the organ, and internal pressure causes a rupture. It also may result from a deep penetrating wound caused by trauma or as a result of diagnostic or therapeutic interventions, such as rectal perforation during rectal examination.

  • bladder p. usually the result of obstructive urolithiasis with eventual leakage of urine into the peritoneal cavity. See also congenital urinary bladder rupture.
  • eardrum p. occurs when an infectious process erodes the tympanic membrane or leads to increased pressure in the middle ear.
  • esophageal p. causes local cellulitis and obstruction of the esophagus and can cause life-threatening pneumomediastinum, mediastinitis, or pneumothorax.
  • gallbladder p. sometimes occurs as a complication of cholecystitis and gallstones. When the gallbladder is infected, necrosis can progress to the point of destroying the wall so that the bile spills out into the abdominal cavity causing biliary peritonitis.
  • intestinal p. a complication of ulcerative colitis (see colitis), intestinal obstruction, ulceration, and other disorders in which there is inflammation of the intestinal wall or obstruction of the intestinal lumen.
  • ulcer p. a complication of duodenal and gastric ulcers.
  • urethral p. is usually a result of obstructive urolithiasis; urine collects in a ventral subcutaneous site.

• perforin [pur′f -rin] a protein in cytotoxic T lymphocytes that creates transmembrane pores that act as ion channels in the target cell. Structurally and chemically related to C9 protein of complement that performs a similar function.

• performance [p r-for′m ns] in the context of animals, a comprehensive term including productivity, racing performance, reproductive efficiency, and any other form of activity that contributes to the owner’s financial and psychological welfare.

  • p. diet one formulated to be high in energy, fat, and protein, and highly digestible. Used not only for performance animals, but also suitable for other above-maintenance requirements such as reproduction, lactation, growth, stress, and after surgery or trauma.
  • p. testing a widely used technique in agricultural animals. Sample animals are tested in controlled surroundings and on controlled diets and ranked in the order of their productivity, e.g., bull test stations.

• performing animals animals trained to perform unusual acts as an entertainment for humans. The practice could be subject to cruel procedures, and the animals could be brutalized to perform painful movements. Of some importance is the imposition by humans of training in tricks that are demeaning to the animals and hold them up to ridicule.

• perfusate a liquid that has been subjected to perfusion.

• perfusion [p r-fu′zh n] 1. the act of pouring through or over; especially the passage of a fluid through the vessels of a specific organ. 2. a liquid poured through or over an organ or tissue.

  • p. pressure the gradient between arterial blood pressure and venous pressure in a comparable location in the vascular tree.

• pulmonary p. blood flow through the pulmonary capillaries.

  • renal p. the rate of perfusion in the kidney is much higher than in any other organ. The rate of formation of urine depends to a large extent on the perfusion rate.
  • p. scan using pulmonary scintigraphy, radionucleotide agents injected into a peripheral vein can be detected where they are trapped in the pulmonary capillary bed. Used to assess pulmonary blood flow.
  • p. technique maintenance of blood circulation to tissues during cardiopulmonary bypass.
  • p.:ventilation ratio see ventilation: perfusion ratio.

• pergolide [pur′go-līd] a dopamine receptor agonist used in the treatment of equine Cushing’s disease (ECD), also known as equine pituitary pars intermedia dysfunction (PPID) in horses.

• peri- word element. [Gr.] around, near. See also words beginning para-.

• periacinar see acinar, centrilobular.

• periadenitis [per″e-ad″ -ni′tis] inflammation of tissues around a gland.

• periadnexal in dermatology, surrounding or in the vicinity of pilosebaceous units (hair follicles and sweat glands). See also periglandular infiltrates.

• periampullary [per″e-am′pu-lar″e] situated around an ampulla.

• perianal [per″e-a′n l] around the anus.

  • p. abscess under the skin outside the anal canal. Causes sufficient pain to inhibit defecation.
  • p. fistulae a syndrome of inflammation, ulceration, and draining sinuses and fistulae in the perianal region of dogs, particularly German shepherds. The lesions include fistulae of the anal sinuses, anal sac rupture and fistulae, submucous fistulae, and sinuses and fistulae of the rectum. Clinical signs include painful defecation and unpleasant odor. A variety of medical treatments and surgical techniques have been developed, but the condition can be very resistant to treatment. Called also anal furunculosis.
  • p. gland modified sebaceous glands found in skin around the anus of dogs. Other regions also contain modified glands, e.g., the perineum, prepuce, thigh, dorsal lumbosacral area, and tail base. Called also circumanal glands, hepatoid glands.
  • p. gland hyperplasia focal perianal swellings in male dogs are commonly due to hormone-dependent hyperplasia and regress following castration.
  • p. gland tumors nodular hyperplasia, adenomas, and carcinomas are common in older male dogs, occurring occasionally in females.
  • p. pyoderma see perianal fistulae (above).
  • p. sinus see perianal fistulae (above).
  • p. warts papilloma around anus, virus possibly transmitted by veterinarian performing rectal examination.

• periangiitis [per″e-an″je-i′tis] inflammation of the tissue around a blood or lymph vessel.

• periangiocholitis [per″e-an″je-o-ko-li′tis] inflammation of tissues around the bile ducts; pericholangitis.

• periaortitis [per″e-a″or-ti′tis] inflammation of tissues around the aorta.

• periapical [per″e-ap′ľ-k l] surrounding the apex of the root of a tooth.

  • p. abscess acute or chronic inflammation of the periapical tissues characterized by localized accumulation of suppuration.
  • p. cyst odontogenic cyst formed around the apex of a tooth after stimulation and proliferation of epithelial rests in the periodontal ligament (also known as a radicular cyst).

• periaqueductal gray [per″e-ak″wľ-duk′t l] a core of gray matter nervous tissue surrounding the cerebral aqueduct in the midbrain.

• periarterial [per″e-ahr-tēr′e- l] near or around an artery.

• periarteriolar lymphoid sheath [per″e-ahr-tē-re-o′l r] splenic white pulp, containing mainly T lymphocytes, surrounding arteries.

• periarteritis [per″e-ahr″t -ri′tis] inflammation of the outer coat of an artery and of the tissues surrounding it.

  • p. nodosa an inflammatory disease of the coats of small and medium-sized arteries, marked by a variety of systemic signs. Seen sporadically in domestic animals. See also collagen diseases. Called also Kussmaul’s disease, polyarteritis, panarteritis nodosa.

• periarthritis [per″e-ahr-thri′tis] inflammation of the tissues around a joint.

• periarticular [per″e-ahr-tik′u-l r] situated around a joint.

  • p. osteophytes bony excrescences around the periphery of a joint.

  P-29.

  

  Severe perianal fistula in a German shepherd dog. (A) associated with stricture formation and severe constipation (B)

• periauricular cyst [per″e-aw-rik′u-l r] dentigerous cyst.

• periaxial [per″e-ak′se- l] around an axis.

• periaxillary [per″e-ak′sľ-lar″e] around the axilla.

• periblast [per″e-blast′] the portion of the blastoderm of telolecithal eggs, the cells of which lack complete cell membranes.

• peribronchial [per″e-brong′ke- l] around a bronchus or bronchi.

• peribronchiolar [per″e-brong-ki′o-l r] around the bronchioles.

• peribronchiolitis [per″e-brong″ke-o-li′tis] inflammation of the tissues around the bronchioles.

• peribronchitis [per″e-brong-ki′tis] a form of bronchitis consisting of inflammation and thickening of the tissues around the bronchi.

• pericallosal [per″e-k -lo′s l] situated around the corpus callosum.

• pericalyceal, pericaliceal [per″e-kal″ľ-se′ l] situated near or around a renal calyx.

• pericardectomy [per″e-kahr-dek′t -me] pericardiectomy.

• pericardiac [per″e-kahr′de-ak] pertaining to the pericardium; around the heart.

• pericardial [per″e-kahr′de- l] pertaining to the pericardium.

  • p. diaphragmatic hernia see peritoneopericardial hernia.
  • p. effusion accumulation of fluid within the pericardial space; may be due to pericarditis, when much inflammatory exudate accumulates, part of a general edematous state, or neoplasia. In dogs, it is commonly associated with hemangiosarcoma of the right atrium or heart base chemodectoma, but idiopathic pericardial effusion also occurs. Characterized by enlargement of the cardiac silhouette on radiography and outline on percussion, muffling of heart sounds, and congestive heart failure due to compression of the heart by cardiac tamponade.
  • p. fibrosis a chronic change in pericarditis, leading to constriction that limits diastolic ventricular volume. See also constrictive pericarditis.
  • p. friction rub see pericardial rub.
  • p. inflammation see pericarditis.
  • p. knock an early diastolic sound caused by loss of pericardial elasticity accompanying fibrosis that limits ventricular filling.

    P-30.

    

    Thoracic radiograph of a dog with pericardial effusion. There is a large, globoid heart

  • p. paracentesis see pericardiocentesis.
  • p. tamponade see cardiac tamponade.
  • p. window surgical excision of part of the pericardial sac to provide drainage of the pericardium, usually to relieve cardiac tamponade.

• pericardicentesis [per″e-kahr″de-sen-te′sis] pericardiocentesis.

• pericardiectomy [per″e-kahr″de-ek′t -me] excision of a portion of the pericardium. A form of treatment for pericardial effusion and cardiac tamponade. See also pericardiostomy.

• pericardiocentesis [per″e-kahr″de-o-sen-te′sis] surgical puncture of the pericardial cavity with aspiration of fluid, usually for the purpose of obtaining fluid for cytological examination or to relieve cardiac tamponade.

• pericardiolysis [per″e-kahr″de-ol′ľ-sis] the operative freeing of adhesions between the visceral and parietal pericardium.

• pericardiophrenic [per″e-kahr″de-o-fren′ik] pertaining to the pericardium and diaphragm.

• pericardiopleural [per″e-kahr″de-o-ploor′ l] pertaining to the pericardium and pleura.

• pericardiorrhaphy [per″e-kahr″de-or′ -fe] suture of the pericardium.

• pericardiostomy [per″e-kahr″de-os′t -me] creation of an opening into the pericardium, usually for drainage of effusions.

• pericardiotomy [per″e-kahr″de-ot′ -me] incision of pericardium.

  • balloon p. a balloon placed in the pericardial space by percutaneous catheterization is used to create a window in the pericardium. Used in treatment of recurring pericardial effusion and cardiac tamponade.
  • pericarditis [per″e-kahr-di′tis] inflammation of the pericardium. Initially there is an audible friction rub on auscultation. Later as fluid accumulates there is a muffling of the heart sounds and sometimes a washing machine sound on auscultation especially if gas produced by bacteria is present. Congestive heart failure develops terminally. Classified according to exudate produced as fibrinous, fibrinohemorrhagic, hemorrhagic, purulent.
  • bread-and-butter p. see bread and butter pericarditis.
  • constrictive p. adhesions between the epicardium and pericardium may limit filling of the heart sufficiently to cause congestive heart failure. See also cardiac tamponade.
  • niche p. an abattoir finding in normal cattle; small red velvety patches on the outside of the great vessels.
  • traumatic p. occurs in cattle and goats, rarely sheep, when a sharp foreign body is swallowed and lodges in the reticulum, subsequently perforating its wall. The perforation may go as far forward as the pericardial sac, especially if the animal is pregnant. The animal dies of a combination of congestive heart failure and toxemia due to the bacterial infection and restrictive pericarditis. See also traumatic reticulopericarditis.

• pericardium [per″ľ-kahr′de- m] the fibroserous sac enclosing the heart and the roots of the great vessels, composed of external (fibrous) and internal (serous) layers; the serous layer is, in turn, divided into a parietal part that lines the fibrous pericardium, and a visceral part that coats the heart muscle. See also pericardial.

  • adherent p. one abnormally connected with the heart by dense fibrous tissue.
  • congenitally absent p. the heart lies free in the pleural sac; recorded in dogs.
  • fibrous p. the external layer of the pericardium, consisting of dense fibrous tissue.
  • parietal p. the parietal layer of the serous pericardium, which is in contact with the fibrous pericardium.

    P-31.

    

    Purulent traumatic pericarditis

  • serous p. the inner, serous portion of pericardium, consisting of two layers, visceral and parietal; the space between the layers is the pericardial cavity.
  • visceral p. the inner layer of the serous pericardium, which is intimately attached to the heart and roots of the great vessels. Called also epicardium.

• pericecal [per″e-se′k l] around the cecum.

• pericecitis [per″e-se-si′tis] inflammation of the tissues around the cecum.

• pericellular [per″e-sel′u-l r] surrounding a cell.

• pericervical around the cervix, especially the uterine cervix.

  • p. abscess caused by trauma during parturition or laceration during mating. May cause infertility.

• pericholangitis [per″e-ko″lan-ji′tis] inflammation of tissues surrounding the bile ducts; periangiocholitis.

• pericholecystitis [per″e-ko″l -sis-ti′tis] inflammation of tissues around the gallbladder.

• perichondrial, perichondral [per″ľ-kon′dre- l] pertaining to or composed of perichondrium.

  • p. mineralization aberrant deposits of calcium salts in the perichondrium.
  • p. ring surrounds and supports the growth plate at the end of each long bone.

• perichondritis [per″e-kon-dri′tis] inflammation of the perichondrium.

• perichondrium [per″ľ-kon′dre- m] the layer of fibrous connective tissue investing all cartilage except the articular cartilage of synovial joints.

• perichordal [per″e-kor′d l] surrounding the notochord.

• perichoroidal [per″e-kor-oi′d l] surrounding the choroid coat of the eye.

• pericolic [per″e-kol′ik] around the colon.

• pericolitis, pericolonitis [per″e-ko-li′tis] inflammation around the colon, especially of its peritoneal coat.

• pericolpitis [per″e-kol-pi′tis] inflammation of the tissues around the vagina; perivaginitis.

• periconchal [per″e-kong′k l] around the concha; preauricular.

• pericorneal [per″e-kor′ne- l] around the cornea.

• pericoronal [per″e-kor′ -n l] around the crown of a tooth.

• pericoronitis [per″e-kor″o-ni′tis] inflammation of the gums around a crown, usually associated with eruption.

• pericranitis [per″e-kra-ni′tis] inflammation of the pericranium.

• pericranium [per″e-kra′ne- m] the external periosteum of the skull.

• pericystitis [per″e-sis-ti′tis] inflammation of tissues about the bladder.

• pericyte [per′e-sīt] one of the peculiar elongated, contractile cells found wrapped about precapillary arterioles outside the basement membrane.

• pericytial [per″e-si′te- l] around a cell.

• periderm [per′ľ-durm″] the outer layer of the bilaminar fetal epidermis, generally disappearing before birth. Called also epitrichium.

• peridesmitis [per″e-dez-mi′tis] inflammation of the peridesmium.

• peridesmium [per″ľ-dez′me- m] the areolar membrane that covers the ligaments.

• perididymis [per″ľ-ep″ľ-did′ -mis] the tunica vaginalis testis, the membrane covering the front and sides of the testis and epididymis.

• perididymitis [per″ľ-did″ -mi′tis] inflammation of the tunica vaginalis testis.

• peridiverticulitis [per″e-di″v r-tik″u-li′tis] inflammation around an intestinal diverticulum.

• periductal [per″e-duk′t l] around a duct.

• periduodenitis [per″e-doo″o-d -ni′tis] inflammation around the duodenum.

• peridural [per″e-doo′r l] external to the dura mater.

• periencephalitis [per″e-en-sef″ -li′tis] inflammation of the surface of the brain.

• periencephalomeningitis [per″e-en-sef″ -lo-men″in-ji′tis] inflammation of the cerebral cortex and meninges.

• perienteritis [per″e-en″t r-i′tis] inflammation of the peritoneal coat of the intestines.

• periesophageal [per″e- -sof′-je- l] around the esophagus.

  • p. hiatal hernia see paraesophageal hernia.

• periesophagitis [per″e- -sof′ -ji′tis] inflammation of the tissues around the esophagus.

• perifistular [per″e-fis′tu-l r] around a fistula.

• perifollicular [per″e-f -lik′u-l r] surrounding a follicle.

• perifolliculitis [per″e-f -lik″u-li′tis] histologic term for inflammation around the hair shaft and hair bulb.

  • nodular granular p. see Majocchi’s granuloma.

• perigangliitis [per″e-gang″gle-i′tis] inflammation around a ganglion.

• perigastric [per″e-gas′trik] around the stomach; pertaining to the peritoneal coat of the stomach.

• perigastritis [per″e-gas-tri′tis] inflammation of the peritoneal coat of the stomach.

• periglandular infiltrates [per″e-glan′du-l r] in dermatohistopathology, dermal cellular infiltrates around glands. Called also periadnexal.

• perihepatic [per″e-h -pat′ik] around the liver.

• perihepatitis [per″e-hep″ -ti′tis] inflammation of the peritoneal coat of the liver and the surrounding tissue.

• peri-islet [per″e-i′let] situated around the islets of Langerhans.

• perijejunitis [per″e-je″joo-ni′tis] inflammation around the jejunum.

• perikaryon [per″e-kar′e-on] the cell body of a neuron.

• perilabyrinthitis [per″e-lab″ -rin-thi′tis] inflammation of the tissues around the labyrinth.

• perilacunar [per″e-l -ku′n r] around the lacunae.

• perilaryngitis [per″e-lar″in-ji′tis] inflammation of the tissues around the larynx.

• perilenticular [per″e-len-tik′u-l r] around the crystalline lens.

• perilesional [per″e-le′zh n- l] located or occurring around a lesion.

• perilimbic, perilimbal [per″e-lim′bik, per″e-lim′b l] around the limbus of the eye.

• perilipin a protein found on the surface of lipid droplets in adipose tissue; regulates lipid metabolism in adipocytes by protecting the stored lipid from breakdown when inactive and by promoting lipolysis when activated by phosphorylation.

• Perilla frutescens [p -ril′] North American plant, in the family Lamiaceae, containing ipomeanol-like toxins which cause acute bovine pulmonary emphysema (atypical interstitial pneumonia). Called also purple mint plant, beafsteak plant.

• perilla mint ketone [p -ril′] toxic ketone found in Perilla frutescens (perilla mint bush, beafsteak plant) causes atypical interstitial pneumonia in cattle.

• perilymph, perilympha [per′e-limf, per″e-lim′f ] the fluid contained in the space separating the membranous and osseous labyrinths of the ear.

• perilymphangitis [per″e-lim″fan-ji′tis] inflammation around a lymphatic vessel.

• perimeningitis [per″e-men″in-ji′tis] pachymeningitis; inflammation of the dura mater.

• perimetritis [per″ľ-m -tri′tis] a localized inflammation of the tissues around the uterus.

• perimetrium [per″ľ-me′tre- m] the serous membrane enveloping the uterus.

• perimyelitis [per″e-mi″ -li′tis] inflammation of (1) the pia of the spinal cord, or (2) the endosteum.

• perimyositis [per″e-mi″o-si′tis] inflammation of connective tissue around a muscle.

• perimysiitis [per″e-mi″se-i′tis] inflammation of the perimysium; myofibrositis.

• perimysium [per″ľ-mis′e- m] connective tissue demarcating a fascicle of skeletal muscle fibers.

• perinatal [per″e-na′t l] relating to the period shortly before and after birth; the actual time varies between species. The last 5–8% of the pregnancy before parturition to the end of a comparable period after birth would cover present usage of the term.

  • p. mortality the percentage of animals in the danger period that die, as a ratio of the total number exposed.

• perinatologist [per″e-na-tol′ -jist] a specialist in perinatology.

• perinatology [per″e-na-tol′ -je] the branch of veterinary medicine (obstetrics and pediatrics) dealing with the fetus and the newborn during the perinatal period.

• perineal [per″ľ-ne′ l] pertaining to the perineum.

  • p. body central tendon of the perineum. The fibromuscular mass in the median plane between the anus and vulva or anus and bulbus penis of the perineum where the bulbospongiosus, external anal sphincter, the levator ani, and transverse perineal muscles attach. Called also centrum tendineum perinea, perinea, corpus perineale.

    P-32.

    

    Bilateral perineal swelling in a Dachshund diagnosed with perineal hernia

  • p. fistula see perianal fistula.
  • Gelpi p. retractor a small self-retaining tissue retractor. More commonly simplified to Gelpi retractor.
  • p. hernia a defect in the pelvic (perineal) diaphragm that permits deviation of the rectum and protrusion of pelvic fat and abdominal contents, particularly the prostate and urinary bladder. Clinical signs include a uni- or bilateral ventrolateral perianal swelling with constipation or straining. Seen most often in middle-aged, entire male dogs, but occurs rarely in females and in cats.
  • p. laceration laceration of the perineal area such as by the birth of a foal. Three degrees of severity are recognized. First degree laceration is when only the mucosa of the vulva and vagina are involved. Second degree is when the submucosa and muscularis layers of the vulva, the anal sphincter, and the perineal body are involved. Third degree is when there is also tearing through the rectovaginal septum, the muscles of the vagina and rectum, and the perineal body.
  • p. reconstruction various surgical techniques used to repair perineal lacerations. It is necessary to reconstruct the rectal floor and vaginal roof in addition to closing the space (the perineal body) between these structures.

    P-33.

    

    Second-degree perineal laceration showing tearing of the dorsal commissure of the vulva

  • p. reflex stimulation of the perineum causes contraction of the anal sphincter and flexion of the tail. It is a test of the integrity of the caudal spinal segments and the pudendal nerve. Called also the anal reflex.
  • p. sling a surgical technique that uses a fascial strip under the urethra to increase resistance to urine flow in the treatment of urinary incontinence.

• perineocele [per″ľ-ne′o-sēl] a hernia between the rectum and the prostate or between the rectum and the vagina.

• perineomelia [per″ľ-ne′o-mel′e- ] an ectopic limb which projects from the perineum.

• perineoplasty [per″ľ-ne′o-plas″te] plastic repair of the perineum.

• perineorrhaphy [per″ľ-ne-or′ -fe] suture of the perineum.

• perineotomy [per″ľ-ne-ot′ -me] incision of the perineum.

• perineovaginal [per″ľ-ne″o-vaj′ľ-n l] pertaining to or communicating with the perineum and vagina.

• perinephric [per″e-nef′rik] around the kidney.

  • p. pseudocyst see feline perirenal pseudocysts.

• perinephritis [per″e-n -fri′tis] inflammation of the perinephrium.

• perinephrium [per″ľ-nef′re- m] the peritoneal envelope and other tissues around the kidney.

• perineum [per″ľ-ne′ m] the region between the tail and the ischiatic arch, especially the region between the anus and genital organs made up of the pelvic diaphragm and associated structures occupying the pelvic outlet, bounded ventrally by the pelvic symphysis, laterally by the ischial tuberosities, and dorsally by the coccygeal vertebrae. During parturition the perineum may be torn, resulting in possible damage to the anal sphincter and impairment of the vulvar seal, which serves to prevent infection of the more cranial reproductive tract. To avoid a perineal laceration, the veterinarian may cut the perineum just before delivery and suture the incision after delivery. See also episiotomy, perineorrhaphy.

• perineural [per″ľ-noor′ l] around a nerve.

  • p. block see perineural block.

• perineuritis [per″e-n $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -ri′tis] inflammation of the perineurium.

• perineurium [per″e-noor′e- m] the connective tissue sheath surrounding each bundle (fascicle) of nerve fibers in a peripheral nerve.

• perinuclear space [per″e-noo′kle- r] the space between the inner and outer nuclear membranes.

• perioceutics [pēr″e-o-soo′tiks] topical application of medication into the periodontal pockets.

• periocular [per″e-ok′u-l r] around the eye.

  • p. hemorrhage a sign of viral hemorrhagic septicemia, several systemic bacterial infections, and vitamin C deficiency in fish.

• periodic repeated or recurring at intervals. See also cyclical.

• periodicity [pēr″e-o-dis′ľ-te] recurrence at regular intervals of time.

  • circadian p. every 24 hours.
  • diurnal p. twice daily.

• periodontal [per″e-o-don′t l] around a tooth; pertaining to the periodontium.

  • p. abscess a localized, acute infection that may drain into the gingival pocket or directly through the gum. There is often local bone destruction. See also malar abscess.
  • p. charting recording the periodontal indices in dental records.
  • p. disease any disease or disorder of the periodontium. See also gingivitis and periodontitis.
  • p. fibrous hyperplasia see periodontal fibromatous epulis.
  • p. indices indicators of periodontal health; includes amount of plaque and calculus, changes in the gingiva, probing depth, evaluation of attachment, and grade of mobility.
  • p. ligament the connective tissue that occupies the space between each tooth and its socket and that suspends the tooth.
  • p. pocket a deep space between the gingiva and the crown or root of a tooth. It can be the result of hyperplasia of the gingiva (pseudopocket or false pocket) or migration of the epithelial attachment toward the apex (true pocket).
  • p. probe a round or flat instrument with markings on the side to measure the depth in millimeters of the gingival sulcus or periodontal pocket. See also periodontal probing (below).
  • p. probing measuring the depth of a gingival sulcus or periodontal pocket in millimeters, using a periodontal probe. Increased probing depth occurs with attachment loss.
  • p. pseudopocket gingival hyperplasia or swelling causes increase in gingival height and thereby increased sulcus depth, but the periodontal ligament and alveolar bone are normal. Called also false pocket.

• periodontics [per″e-o-don′tiks] the branch of dentistry dealing with the study and treatment of diseases of the periodontium.

• periodontist [per″e-o-don′tist] a dentist who specializes in periodontics.

• periodontitis [per″e-o-don-ti′tis] the more severe form of periodontal disease, resulting in attachment loss, gingival recession, furcation exposure, periodontal pocket formation, loss of alveolar bone, and mobility and loss of the tooth plaque–induced inflammation. The condition is caused by residual food, bacteria, and calcium deposits (tartar) that collect in the spaces between the gum and lower part of the tooth crown. If it continues unchecked, the inflammation will spread to the bone in which the teeth are rooted. The bone then resorbs, and the teeth are slowly detached from their supporting tissues. A common problem in dogs and cats and in sheep, causing premature loss of teeth and in the case of sheep, culling. Called also peridentitis, pyorrhea. See also cara inchada.

  P-34.

  

  A periodontal probe used to evaluate the depth of the periodontal pocket

• periodontium [per″e-o-don′she- m] pl. periodontia [L.] the tissues investing and supporting the teeth, including the periodontal ligament, cementum, alveolar bone, and gingiva.

• periomphalic [per″e-om-fal′ik] situated around the umbilicus.

• perionychia [per″e-o-nik′e- ] see paronychia.

• perionychium [per″e-o-nik′e- m] the epidermis bordering a nail or claw.

• perioophoritis [per″e-o-of″o-ri′tis] inflammation of the tissues around the ovary.

• perioophorosalpingitis [per″e-o-of″o-ro-sal″pin-ji′tis] inflammation of the tissues around the ovary and oviduct.

• perioperative [per″e-op′ r- -tiv] pertaining or relating to the period immediately before and/or after an operation, as perioperative care. Usually relates to immediately before, as in perioperative antibiotics, extending to just after.

• periophthalmic [per″e-of-thal′mik] periocular.

• periople [per′e-o″p l] the layer of soft, light-colored horn that covers the coronary border of the hoof in ungulates and serves as a transition between soft skin and hard hoof wall.

• perioplic [per″e-o′plik] pertaining to or emanating from periople.

• perioral [per″e-or′ l] around the mouth.

• periorbita [per″e-or′bľ-t ] the fascial sheet that encloses the eye and its muscles that is continuous medially with the periosteum of the bones forming the orbit.

• periorbital [per″e-or′bľ-t l] around the eye socket.

  • p. eczema ovine staphylococcal dermatitis.

• periorbitis inflammation of the periorbita.

• periorchitis [per″e-or-ki′tis] inflammation of the tunica vaginalis testis; vaginalitis.

• periorchitis–orchitis [per″e-or-ki′tis] inflammation of the investing membranes, the tunica vaginalis of the testis and the testicular parenchyma.

• periosteal [per″e-os′te- l] pertaining to or emanating from the periosteum.

  • p. bud a stage in the development of bone to replace existing cartilage; periosteal bud formation results in the removal of calcified cartilage.
  • p. elevator a heavy metal instrument, with a broad, flat thin end for prising between periosteum and bone and lifting the periosteum prior to working on the bone. See also Sayre elevator, Matson elevator.
  • p. reaction production of new bone by the periosteum in response to injury or irritation.
  • p. stripping may occur in association with fractures, damaging vascular supply and delaying callus formation.

• periosteitis [per″e-os″te-i′tis] periostitis.

• periosteoma [per″e-os-te-o′m ] a morbid bony growth surrounding a bone.

• periosteomyelitis [per″e-os″te-o-mi″ -li′tis] inflammation of the entire bone, including periosteum and marrow.

• periosteophyte [per″e-os′te-o-fīt″] a bony growth on the periosteum.

• periosteotomy [per″e-os″te-ot′ -me] incision of the periosteum.

• periosteum [per″e-os′te- m] a specialized connective tissue covering all bones of the body, and possessing bone-forming potential. It is made up of an outer tough fibrous layer and a deeper more succulent osteogenic layer. Periosteum also serves as a point of attachment for certain muscles, tendons, and ligaments. The connective tissues fuse with the fibrous layers of periosteum.

• periostitis [per″e-os-ti′tis] inflammation of the periosteum.

  • dental p. periodontitis.
  • diffuse p. widespread periostitis of the long bones.

• periostosis [per″e-os-to′sis] abnormal deposition of periosteal bone; the condition manifested by the growth of periosteomas.

• periotic [per″e-o′tik] 1. situated about the ear, especially the internal ear. 2. the petrous and mastoid portions of the temporal bone, at one stage a distinct bone.

• periovarian around the ovary, e.g., periovarian adhesions, cysts.

• peripachymeningitis inflammation of the substance between the dura mater and the bone of the cranium.

• peripancreatitis [per″e-pan″kre- -ti′tis] inflammation of tissues around the pancreas.

• peripapillary [per″e-pap′ľ-lar″e] around a papilla, such as the optic papilla.

  • p. conus a small zone of tapetal hyper-reflectivity immediately surrounding the optic disc due to normal thinning of the retina at this point. Sometimes abbreviated to conus.

• peripartum [per″e-pahr′t m] occurring during the last 10% of the gestation period or the first few weeks after delivery, with reference to the mother.

• periparturient [per″e-pahr-tu′re- nt] see peripartum.

  • p. rise the phenomenon of increase in number of nematode eggs produced by ewes and sows in the period 4–8 weeks before and after parturition. A reduction in the resistance of the dam permits greater establishment and fecundity of the worms.

• periphacitis inflammation about the capsule of the crystalline lens.

• peripharyngeal [per″e-f -rin′je- l] around the pharynx.

• peripherad [p -rif′r- d] toward the periphery.

• peripheral [p -rif′r- l] pertaining to or situated at or near the periphery.

  • p. circulatory failure see circulatory failure.
  • p. gangrenous ergotism see ergotism.
  • p. giant cell granuloma see giant-cell epulis.
  • p. lymphatics see lymphatic.
  • p. nerve see peripheral nerve.
  • p. nerve degeneration see axonal degeneration, Wallerian degeneration.
  • p. nerve paralysis see peripheral nerve.
  • p. nervous system see peripheral nervous system.
  • p. proteins see membrane proteins.
  • p. sinus the peripheral lymph space just beneath the capsule of a lymph node.

• peripheralization [p -rif′r-l-ľ-za′sh n] colonization of other tissues by T lymphocytes from the thymus that populate specific regions of lymph nodes and the periarteriolar zone of splenic corpuscles.

• periphery [p -rif′ -re] an outward structure or surface; the portion of a system outside the central region.

• periphlebitis [per″e-fl -bi′tis] inflammation of the tissues around a vein, or the external coat of a vein.

• periplasmic [per″e-plas′mik] around the plasma membrane; between the plasma membrane and the cell wall of a gram-positive bacterium and between the cytoplasmic and outer cell membrane in a gram-negative bacterium.

• periportal [per″e-por′t l] hepatic parenchyma immediately adjacent to the portal triads.

  • p. necrosis necrosis of periportal hepatocytes; much less common than periacinar necrosis. Caused by some hepatotoxins.

• periproctitis [per″e-prok-ti′tis] inflammation of tissues around the rectum and anus.

• periprostatic [per″e-pros-tat′ik] around the prostate.

• periprostatitis [per″e-pros″t -ti′tis] inflammation of the tissues around the prostate.

• peripylephlebitis [per″e-pi″le-fl -bi′tis] inflammation of tissues around the portal vein.

• peripyloric [per″e-pi-lor′ik] around the pylorus.

• perirectal [per″e-rek′t l] around the rectum in the tissues of the pelvic cavity.

  • p. abscess caused usually by minor perforation of vagina or rectum.

• perirenal [per″e-re′n l] around the kidney.

  • p. edema an exaggeration around the kidney of generalized subserous edema; seen mostly in pigs and cattle.
  • feline p. pseudocysts uni- or bilateral accumulations of fluid in cyst-like masses between the renal parenchyma and capsule or entirely extracapsular occur in aged, often male, cats, causing a progressive abdominal enlargement. They may be associated with chronic kidney disease. Called also perinephric pseudocyst, renal capsular cyst, capsulogenic renal cyst, perirenal hygroma, perirenal cyst, capsular hydronephrosis, and retroperitoneal perirenal cyst.

• perirhinal [per″e-ri′n l] around the nose.

• perisalpingitis [per″e-sal″pin-ji′tis] inflammation of tissues around the uterine tube.

• periscopic [per″ľ-skop′ik] affording a wide range of vision.

• perisinusitis [per″e-si″n s-i′tis] inflammation of the tissues around a sinus.

• perisinusoidal space [per″e-si″n -soi′d l] the space separating sinusoids from hepatocytes; it is occupied by cells, reticular fibers, and hepatocytic microvilli.

• perisplanchnic [per″ľ-splank′nik] around a viscus or the viscera.

• perisplanchnitis [per″e-splank-ni′tis] inflammation of tissues around the viscera.

• perisplenic [per″e-splen′ik] around the spleen.

• perisplenitis [per″e-spl -ni′tis] inflammation of the peritoneal surface of the spleen.

• perispondylitis [per″e-spon″d -li′tis] inflammation of tissues around a vertebra.

• perissodactyl, perissodactylids [p -ris″o-dak′t l] any member of the order Perissodactyla, animals that have an odd number of toes. Includes the pentadactyls, e.g., elephants, tridactyls, e.g., tapir (but only on the hindlimbs, the front limbs have four digits), and the monodactyls, e.g., horses.

• peristalsis [per″ľ-stawl′sis] the wormlike movement by which the alimentary canal or other tubular organs with both longitudinal and circular muscle fibers propel their contents, consisting of a wave of contraction passing along the tube. Increased peristalsis means faster movement of ingesta through the gut and less absorption of fluid, both tending to diarrhea. Reduced peristalsis means a longer alimentary sojourn, greater inspissation of ingesta and a tendency to constipation. See also peristaltic, paralytic ileus.

  • reverse p. peristalsis directed orally is a result of intestinal obstruction and acute, significant distention of the intestinal lumen; it is a major contributing mechanism in vomiting.

• peristaltic [per″ľ-stawl′tik] pertaining to or emanating from peristalsis.

  • p. reflex onward movement of a bolus of ingesta in the intestine is preceded by a reflex dilation of the intestine.
  • p. rush a rapid movement of intestinal contents that results in diarrhea caused by an absence of peristaltic rhythm and sphincter tone.
  • p. sounds made by the vigorous and rapid mixing of fluid and gas by peristaltic movement in the intestines and forestomachs. Are loudest and evocative in the rumen of the cow and the colon and cecum of the horse.

• perisynovial [per″e-sľ-no-ve′ l] around a synovial structure.

• peritendineum [per″ľ-t n-din′e- m] connective tissue investing larger tendons and extending between the fibers composing them.

• peritendinitis, peritenonitis [per″e-ten″dľ-ni′tis] inflammation of the sheath of a tendon; tenosynovitis.

• peritenon [per″ľ-te′non] the connective tissue structures attached to and surrounding a tendon.

  P-35.

  

  Representation of peristalsis. Muscular contraction within the tube forces the food bolus along. Aspinall, V., Cappello, M. Introduction to Veterinary Anatomy and Physiology Textbook, 3rd ed. Butterworth-Heinemann, 2015

• perithelioma [per″ľ-the″le-o′m ] see hemangiopericytoma.

• perithelium [per″e-the′le- m] the connective tissue layer surrounding the capillaries and smaller vessels.

• perithyroiditis [per″e-thi″roi-di′tis] inflammation of the capsule of the thyroid.

• peritomy [p -rit′ -me] surgical incision into the conjunctiva and subconjunctival tissue about the whole circumference of the cornea as would be performed as part of a transconjunctival enucleation.

• peritoneal [per″ľ-to-ne′ l] pertaining to the peritoneum.

  • continuous ambulatory p. dialysis the use of an indwelling catheter with external tubing that is strapped to the body wall when not being used for infusion and drainage of the dialysate fluid.
  • p. cysts include vestigial remnants of primordial urogenital organs, cestode intermediate stages, inclusion cysts or lymphatic ectasia.
  • p. dialysis the employment of the peritoneum surrounding the abdominal cavity as a dialyzing membrane for the purpose of removing accumulated waste products or toxins. In veterinary medicine, the main indication is acute, reversible renal failure. Certain crystalloids such as urea, creatinine, and electrolytes, and some drugs, such as the salicylates, bromides, and barbiturates, can be removed. Fluid equal in osmolarity and similar in chemical composition to normal body fluid is introduced into the peritoneal cavity via a catheter. After a period of time (‘dwell time’) determined by the molecular weight of the substance being used as the dialyzing solution, the fluid is drained and the cycle repeated.
  • p. implantation attachment and growth of other tissues to the peritoneum, e.g., a fetus escaped from the genital tract, direct metastasis of malignant tumors.
  • p. lavage see abdominal lavage.
  • p. lymph the fluid normally present in very small amount in the peritoneal cavity.
  • p. membrane see peritoneum.

• peritoneocentesis [per″ľ-to″ne-o-sen-te′sis] paracentesis of the abdominal (peritoneal) cavity.

• peritoneoclysis [per″ľ-to″ne-ok′lľ-sis] injection of fluid into the peritoneal cavity.

• peritoneography [per″ľ-to″ne-og′r -fe] imaging of the peritoneal cavity.

• peritoneopathy [per″ľ-to-ne-op′ -the] any disease of the peritoneum.

• peritoneopericardial [per″ľ-to-ne″o-per″ľ-kahr′de- l] pertaining to the peritoneum and pericardium.

  • p. hernia anomalous development of the diaphragm and pleuropericardial membranes that allows herniation of variable amounts of abdominal contents into the pericardial sac. May cause dyspnea, tachypnea, vomiting, diarrhea, cardiac tamponade, and congestive heart failure, but some cases are only detected incidentally at postmortem examination. Seen in dogs and cats.

• perispermatitis [per″e-sper″m -ti′tis] inflammation of tissues around the spermatic cord.

• peritoneoscope [per″ľ-to′ne-o-skōp″] an endoscope for use in peritoneoscopy.

• peritoneoscopy [per″ľ-to″ne-os′k -pe] endoscopic examination of the organs of the abdominal (peritoneal) cavity.

• peritoneotomy [per″ľ-to″ne-ot′ -me] incision into the peritoneum.

• peritoneovenous [per″ľ-to-ne″o-ve′n s] communicating with the peritoneal cavity and the venous system. See also LeVeen shunt.

• peritoneum [per″ľ-to-ne′ m] the serous membrane lining the walls of the abdominal and pelvic cavities (parietal peritoneum) and investing contained viscera (visceral peritoneum), the two layers enclosing a potential space, the peritoneal cavity. The diseases that are important in the peritoneum of animals are peritonitis, including a special group of rectal tear, retroperitoneal abscess, lipomatosis, neoplasia, ascites, and peritoneal effusion.

• peritonitis [per″ľ-to-ni′tis] inflammation of the peritoneum. The cause may be infectious or chemical. Typical signs are rigidity and pain on palpation of the abdominal wall, absence of feces, severe toxaemia, and fever. In horses, there is colic, and in dogs and cats, there is often effusion. Paracentesis may show evidence of inflammation.

  • acute diffuse p. in the early stages pain is evident all over the abdomen. There is soon a disappearance of pain, a profound premortal toxemia develops that may mask the presence of diffuse peritonitis.
  • acute local p. added to the usual signs there is a sharp pain response over the site of the lesion.
  • adhesive p. peritonitis characterized by adhesions between adjacent serous structures.
  • aseptic p. see chemical peritonitis (below).
  • biliary p., bile p. leakage of bile from the common bile duct or gallbladder may occur as a result of trauma, including perforation during percutaneous needle biopsy of the liver, and (rarely) erosion from biliary calculi. A chemical peritonitis results and may be fatal unless surgical repair is accomplished.
  • chemical p. may be caused by leakage of bile, urine, gastric juices, or pancreatic enzymes in acute pancreatitis. Infusion of irritant materials can cause a similar chemical irritation.
  • chronic p. is manifested by chronic toxemia, bouts of colic due to adhesions and an accumulation of exudate which may cause a visible distention of the abdomen. See also retroperitoneal abscess.
  • chylous p. an uncommon result of abdominal trauma or tumors, intestinal obstruction, or lymphangiectasia.
  • egg p. peritonitis in birds or reptiles due to release of an egg into the coelomic cavity with subsequent infection, for example, by Escherichia coli, which have ascended via the oviduct.
  • feline infectious p. (FIP) see feline infectious peritonitis.
  • idiopathic p. one caused by a primary infection of the peritoneal cavity, e.g., feline infectious peritonitis, or hematogenous spread from a noncontiguous site.
  • poststripping p. fatal peritonitis occurring in cultured salmonid fish soon after stripping, sometimes before. Caused by a number of gram-positive cocci and coccobacilli; Carnobacterium piscicola considered to be the most important infection.
  • primary p. see idiopathic peritonitis (above).
  • septic p. secondary to disruption of the abdominal cavity or a hollow viscus, particularly leakage from the gastrointestinal tract.
  • silent p. asymptomatic peritonitis.
  • starch granulomatous p. talcum powder, and to a lesser extent, other powders used on surgical gloves can cause a granulomatous reaction on the peritoneum.
  • traumatic p. perforation of the gut wall or abdominal wall introducing infection into the peritoneal cavity. May result from stake or bite wound, inexpert passing of urinary or insemination catheter, sadistically by a broom handle in the vagina, or stabbing of the rumen as an emergency measure in acute ruminal tympany. See also traumatic reticuloperitonitis.
  • urine p. prolonged exposure of the peritoneum to urine, usually due to leakage from the bladder or a ureter, results in a peritonitis and the development of uremia. Bacterial infection may also be introduced.

• peritonsillar [per″e-ton′sľ-l r] around a tonsil.

  • p. abscess a localized accumulation of pus in peritonsillar tissue subsequent to suppurative inflammation of the tonsil. Called also quinsy.

• peritonsillitis [per″e-ton″sľ-li′tis] inflammation of peritonsillar tissues.

• peritracheal [per″e-tra′ke- l] around the trachea.

• peritrichous [p -rit′rľ-k s] 1. having flagella around the entire surface; said of bacteria. 2. having flagella around the cytostome only; said of Ciliophora.

• peritectomy [per″ľ-tek′t -me] excision of a ring of conjunctiva from behind the corneoscleral limbus followed by cautery of the trench. Not done in veternary medicine.

• peritubular [per″e-too′bu-l r] investing the uriniferous tubules.

  • p. plexus a plexus of capillaries formed by the renal intertubular arterioles around cortical uriniferous tubules.
  • p. space water and electrolytes resorbed by tubular epithelium passes into this space.

• periumbilical [per″e- m-bil′ľ-k l] around the umbilicus.

• periureteral [per″e-u-re′t r- l] around the ureter.

• periureteritis [per″e-u-re″t r-i′tis] inflammation of tissues around the ureter.

• periurethral [per″e-u-re′thr l] around the urethra.

• periuterine [per″e-u′t r-in] around the uterus.

• perivaginal [per″e-vaj′ľ-n l] around the vagina.

  • p. needle see gerlach needle.

• perivaginitis [per″e-vaj″ľ-ni′tis] inflammation of tissues around the vagina; pericolpitis.

• perivascular [per″e-vas′ku-l r] around a vessel.

  • p. cellulitis may be caused by the introduction of infection at the time of an injection or the injection of an irritant substance such as thiacetarsamide into tissues while attempting an intravenous injection.
  • p. cuffing the accumulation of lymphocytes or plasma cells in a dense mass around the vessel. An indication of inflammation or of an immune reaction. In the brain, it is indicative of viral infection.
  • p. dermatitis a classification of inflammatory skin disease in which the reaction is centered around superficial or deep dermal blood vessels.

• perivasculitis [per″e-vas″ku-li′tis] inflammation of a perivascular sheath and surrounding tissue.

• periventricular gray [per″e-ven-trik′u-l r] a diffuse mass of neurons and fiber tracts that surrounds the spinal canal and the ventricular system cranial to the mid-cervical region in the medial part of the reticular formation.

• perivenular [per″e-ven′u-l r] around a vein; in the connective tissue about a vein.

• perivesical [per″e-ves′ľ-k l] around the bladder.

• perivesiculitis [per″e-v -sik″u-li′tis] inflammation of tissues around the vesicular glands (seminal vesicles).

• periwinkle [per′e-wing″k l] see Vinca. Includes bigleaf periwinkle (V. major), Madagascan periwinkle (Catharanthus roseus).

• Perkinsus genus of protozoan parasites of molluscan tissues. Includes P. marinus (a major pathogen of the American oyster), P. olseni (a pathogen of abalone in warm waters). The disease is notifiable to the OIE (see Table 20).

• perlèche [per-lesh′] inflammation with exudation, maceration, and fissuring at the labial commissures.

• perloline alkaloid produced in tall fescue (Festuca arundinacea) and perennial ryegrass (Lolium perenne) infected with fungal endophyte (Neotyphodium spp.)

• permanganate [p r-mang′g -nāt] salts of permanganic acid; the potassium salt is an old-fashioned, out-of-favor, weak disinfectant compound that used to be used topically for a variety of skin conditions; historically, used to disinfect water. The purple crystals were also known as Condy’s crystals.

• permeability [pur″me- -bil′ľ-te] the level or degree of the state of being permeable.

• permeable [pur′me- -b l] not impassable; pervious; permitting passage of a substance.

• permease [pur′me-ās] any of a group of transmembrane proteins involved in transporting substances across cell membranes.

• permeate [pur′me-āt″] 1. to penetrate or pass through, as through a filter. 2. the constituents of a solution or suspension that pass through a filter.

• permethrin [p r-meth′rin] a third-generation synthetic pyrethroid widely used in the control of ectoparasites. Topically applied products are used on dogs, but those with higher concentrations of permethrin are toxic to cats.

• permissible dose see dose equivalent limits.

• permissible medication treatments that are permitted of animals before racing or performing or just appearing at shows, race meetings.

• Perna canaliculus [pur′n ] scientific name for the New Zealand greenlipped mussel.

• pernicious [p r-nish′ s] tending to a fatal issue.

  • p. anemia a form of anemia in humans caused by a genetically determined lack of the intrinsic factor, which normally is produced by the stomach mucosa. The deficiency results in inadequate and abnormal formation of erythrocytes, and failure to absorb vitamin B₁₂. Not reported in animals.

• pero- word element. [Gr.] relationship to deformity.

• perobrachius [pe″ro-bra′ke- s] a fetus with deformed forelimbs.

• perocephalus [pe″ro-sef′ -l s] a fetus with a deformed head.

• perochirus [pe″ro-ki′r s] a fetus with deformed forelimb extremities.

• perocormus [pe″ro-kor′m s] obsolete term for abnormalities in the spine, see Perosomus elumbus.

• perodontium [per″o-don′she- m] periodontium.

• peromelia [pe″ro-me′le- ] congenital deformity of the limbs.

• peromelus [pe-rom′ -l s] a fetus with deformed limbs.

• peroneal [per″o-ne′ l] pertaining to the fibula or to the outer side of the leg or shank; fibular.

  • common p. nerve a nerve originating in the sciatic nerve; innervates parts of the calf and foot. See also Table 13.
  • p. muscles see Table 12.4.
  • p. nerve block see peroneal block.

    P-36.

    

    Peromelia in a newborn lamb. Both hind limbs and the left forelimb are affected. The right forelimb is normal

    P-37.

    

    Cow with peroneal paralysis

  • p. nerve paralysis causes a characteristic inability to flex the hock and extend the digits so the animal bears weight on the dorsum of the foot. There is anesthesia of the cranial leg and dorsal paw or foot. Occurs in recumbent cattle and from trauma to the lateral stifle in dogs.

• Peronia rostrata [pe-ro′ne- ] a tertiary blowfly parasitizing carcasses which are tending to dry out.

• peroral [p r-or′ l] by mouth, per os; performed or administered by way of the mouth.

• perosis [p -ro′sis] a disease of young birds, typically poultry, waterfowl, and ratites, often associated with nutritional deficiencies. Usually seen as gross enlargement of the tibiotarsal joint and deformity above and below the joint, with slipping of the gastrocnemius tendon from the condyles. Called also slipped tendon.

• perosomus elumbus [pe″ro-so′m s] a congenital skeletal defect occurring in most animals but most common in calves and lambs. The vertebral column stops at the caudal thoracic region and the posterior part of the body is joined to the front half by soft tissue only.

• Perostrongylus a subgenus of nematodes in the family Filaroididae. See Aelurostrongylus. Parasites of mustelids and rodents.

• peroxidase [p r-ok′sľ-dās] any of a group of iron–porphyrin enzymes that catalyze the oxidation of some organic substrates in the presence of hydrogen peroxide.

  • p. stain a group of staining techniques that demonstrate peroxidases in tissue sections or smears.

• peroxidation [p r-ok″sľ-da′sh n] conversion of oxides to peroxides.

• peroxide [p r-ok′sīd] that oxide of any element containing more oxygen than any other; more correctly applied to compounds having such linkage as −O−O−.

  • hydrogen p. H₂O₂, used in solution as an antibacterial agent. A 3% solution foams on touching skin or mucous membrane and appears to have a mechanical cleansing action. See also hydrogen peroxide–based teat dip.
  • p. value said of a feed sample; an indication of the degree of rancidity of oils and fats in the feed.

• peroxisome [p r-ok′sľ-sōm] a small membrane-bound body found in vertebrate animal cells, especially kidney and liver cells, which contains enzymes (e.g., urate oxidase, amino acid oxidase, catalase) that are involved in various biochemical pathways, including several in energy metabolism.

• perphenazine [p r-fen′ -zēn] a phenothiazine compound used as a tranquilizer and antiemetic.

• Perralderia coronopifolia North American plant in family Asteracea; causes cyanide poisoning, characterized by dyspnea, in camels. Called also tafes, lahiel el tis.

• Perreyia a genus of South American sawflies whose larvae cause severe liver necrosis when ingested; the toxin is lophyrotomin. Includes P. flavipes and P. lepida.

• Perro de Presa Canario a medium- to large-sized (85–100 lb) mastiff-type farm dog, originally from the Canary Islands. The body is muscular and the head broad and powerful with small ears, usually cropped. The fawn or brindle coat is short. The dog can be aggressive to other dogs and humans. Australia and New Zealand ban importation of the breed. Called also Canary mastiff, Presa Canario.

• Persea americana American fruit tree in the Lauraceae family; all parts of the plant except the seed contains the toxic monoglycide persin that causes cardiomyopathy manifested by sudden death in caged birds and by heart failure and severe edema of the head in horses; some horses develop necrosis of masseter muscles and tongue muscles; also causes sterile mastitis in lactating females. Guatemalan varieties and their hybrids are toxic; Mexican varieties are not. Called also avocado, alligator pear.

• Persian the traditional longhaired cat with a broad head, very short nose, cobby body, and a medium to large size, with short legs. A variety of colors are seen in the coat and eyes. Also known as Angora, although originally that was a type with finer, satiny coat, or simply as longhair.

• Persian insect powder see pyrethrum.

• Persicaria plant genus in the Polygonaceae family; contains an unidentified hepatotoxin that causes hepatitis and photosensitive dermatitis, now classified as Polygonum spp.

• persimmon see Diospyros.

• persin monoglyceride toxin in Persea americana (avocado).

• persistent relative to embryological defects refers to persistence of an entity into external life in such a way as to cause some reduction of efficiency. The common defects are listed under the names of the compromised organs. See also persistent right aortic arch, ductus arteriosus, penile preputial frenulum, imperforate hymen, patent urachus, persistent hyperplastic vitreous, persistent pupillary membrane.

  • p. corpus luteum see corpus luteum.
  • p. ductus arteriosus see patent ductus arteriosus.
  • p. ductus venosus see ductus venosus.
  • p. infection see persistent infection.
  • p. omphalomesenteric duct see omphalomesenteric duct.
  • p. posterior perilenticular vascular tunic the tunic is generated in the embryo but atrophies just before birth. Persistence of some part of the tunic into adult life is common but of no clinical significance.
  • p. recumbency the animal is normal in other respects but does not rise to its hooves for a period exceeding 24 hours.
  • p. right aorta arch see persistent right aortic arch.
  • p. truncus arteriosus may cause neonatal congestive heart failure and cyanosis; the interventricular septum is usually patent. See also truncus arteriosus.

• personality [pur″s -nal′ľ-te] that which constitutes, distinguishes and characterizes an animal as an entity over a period of time; the total reaction of an animal to its environment. Many factors that determine personality are inherited; they are shaped and modified by the animal’s environment.

• perspiration [pur″spľ-ra′sh n] see sweat, sweating (1).

  • insensible p. sweat lost from skin and mucosal surfaces that is not secreted by sweat glands.

• pertechnate ion a competitive agent in the uptake and transport of iodine in the thyroid gland.

• perthane a chlorinated hydrocarbon insecticide.

• Perthes’ disease [per′t z] see Legg–Calvé–Perthes disease.

  P-38.

  

  Persian cat

• Peru balsam see balsam.

• peruke bizarre collection of velveted antlers developed by male caribou and roe deer males castrated as adults. Called also wigged.

• Peruvian bark tree see Alstonia constricta.

• Peruvian guinea pig one of the original varieties of guinea pig, characterized by a very long, flowing coat that covers the face. See guinea pig.

• Peruvian Inca orchid a rare hairless sighthound originating in Peru. There are three varieties: small, medium, and large and, as with other hairless dog breeds, there is also a coated variety. Called also Peruvian hairless dog.

• PERV porcine endogenous retrovirus.

• pes pl. pedes [L.] foot; the terminal organ of the lower limb; any footlike part; the tarsus, metatarsus, and digits (the phalanges and sesamoid bones). See also dipes.

  • p. varus a rare condition in Dachshunds associated with distal tibial physeal closure.

• pessary [pes′ -re] 1. an instrument placed in the vagina to support the uterus or rectum or as a contraceptive device. 2. a medicated vaginal suppository.

• pessulus a wedge-shaped cartilage in the syrinx of the fowl, lying at the bifurcation of the trachea and dividing it into the two bronchi.

• pest [pest] 1. an organism that injures, irritates, or damages livestock or crops. 2. a highly fatal, rapidly spreading disease with an acute course. See also plague, peste des petits ruminants, peste du porc, peste suina.

  • fowl p. see avian influenza. Newcastle disease was at one time known as new fowl pest and as pseudo fowl pest.
  • integrated p. management the use of all suitable methods of pest (insect, weed, rodent, etc.) control to keep populations below the economic injury level. Methods include farming practices and the use of biological, physical, and genetic control agents and selective use of pesticides.

• peste des petits ruminants [pest] [Fr.] a highly infectious and fatal disease of sheep and goats caused by a paramyxovirus in the genus Morbillivirus that is very closely related to the rinderpest virus. Typical signs are purulent nasal discharge, erosive stomatitis, diarrhea, and bronchopneumonia. The spread is rapid and the mortality rate high, and it has spread extensively through the developing world. There are effective vaccines and good diagnostics, and the virus is being targeted for global control and eventual eradication See also rinderpest. A disease notifiable to the OIE (see Table 20). Called also pseudorinderpest. An historical name is contagious pustular stomatitis.

• peste du porc [Fr.] hog cholera; now called classical swine fever.

• peste suina [Span.] hog cholera; now called classical swine fever.

• pesticide [pes′tľ-sīd] a poison used to destroy pests of any sort. See arsenical, carbamates, chlorinated hydrocarbons, organophosphorus compound, pyrethroids.

  • p. poisoning pesticides are selective poisons chosen for use because of their relative safety for humans and animals. It is likely that they will poison these species if they are used in sufficient quantity or in special circumstances.
  • p. resistance continued use of a single agent, or a group of closely allied agents, can cause selective survival of insects with innate tolerance of the agent and lead to the development of a resistant population.
  • p. tissue residues some pesticides have had to be withdrawn from use because of their persistence in the tissues of animals including humans. The passage of the agent in the milk of the animal is a comparable problem.
  • banned p. pesticide for which all uses have been prohibited by final regulatory action, in order to protect human health or the environment.
  • restricted use p. in the US the EPA classifies pesticides as general use pesticides and restricted use pesticides. Restricted use pesticides are not available for purchase or use by the general public as they are deemed to have the potential to cause unreasonable adverse effects to the environment and injury to applicators or bystanders. Their use must be by a licensed applicator. Licensing is managed by the individual states and is achieved by examination and subsequent mandatory continuing education.

• pestilence [pes′tľ-l ns] a virulent contagious epidemic or infectious epidemic disease.

• pestis [pes′tis] see plague.

• pestis equorum [pes′tis] see African horse sickness.

• Pestivirus [pes′tľ-vi″r s] a genus in the family Flaviviridae. Four different species or genotypes have been identified in the genus: bovine virus diarrhea virus (BVDV) types I and II, classical swine fever virus (CSFV), and border disease virus (BDV). Isolates from border disease predominantly fall within the BDV genotype, but sheep and goat isolates also fall in the BVDV genotypes. An atypical pestivirus group includes giraffe, pronghorn antelope, and Bungowannah.

• pestle [pes′ l] a small, heavy, club-shaped instrument with a rounded end, used in a mortar to grind or pulverize solids or produce a homogeneous mixture of crushed solids; for example, a mortar and pestle may be used to crush tablets into a powder to be mixed with food.

• PET positron emission tomography, a nuclear medicine technique that combines computed tomography and radioisotope scanning.

• pet a nonfood animal included in a human household. Called also companion animals. Includes dogs, cats, cage birds, aquarium fish, and exotic species such as monkeys, alligators, tortoises, monkeys, big cats, axolotls, newts, yabbies, seahorses, snakes, gerbils, hamsters, mice, rats, and spiders.

  • p.-assisted therapy, p. facilitated therapy the use of animals in a specific medical program as an adjunct to conventional therapy, especially for seriously ill and recuperating persons and persons with psychological problems. See also animal facilitated therapy.
  • children’s p’s those pets that can be properly cared for by children; usually taken to include the common companion pets, dogs, cats, and cage birds, and the unusual species such as lizards, tortoises, terrapins, hamsters, guinea pigs, mice, rats, gerbils, rabbits, and even snakes and spiders.
  • exotic p’s those other than the conventional dogs, cats, aquarium fish, and cage birds.

• PET CT positron emission tomography and computed tomography.

• PETA People for the Ethical Treatment of Animals.

• peta- (P) [Gr.] five; a prefix used in the metric system of naming units of measurement to designate a quantity 10₁₅ (a thousand-million-million or a quadrillion) times the unit.

• -petal word element. [L.] directed or moving toward.

• petechia [p -te′ke-] pl. petechiae [L.] a small (1–2 mm), nonraised, purplish red spot on serosal, mucosal, or cutaneous surfaces. They are small local hemorrhages and indicate a hemorrhagic disorder such as thrombocytopenia or, less often, a paroxysmal increase in blood pressure such as might be associated with convulsions. See also purpura and diathesis.

• petechial fever [p -te′ke- l] see bovine petechial fever.

• petechiation [p -te″ke-a′shun] a state in which petechiae are present.

• Peterbald a Russian breed of cats with a build similar to oriental shorthairs, but with a distinctive hair coat, which varies widely from hairlessness to normal. In between, there may be coats resembling ‘peach fuzz’ or may be wiry and kinky.

• Peter’s anomaly a range of abnormalities of ocular development in which the cornea, lens, and anterior uvea fail to completely or appropriately cleave to form the anterior chamber.

• Peterson block a method for desensitizing the bovine eye and its associated structures for surgery by depositing local anesthetic near the foramen orbitorotundum and over the auriculopalpebral nerve.

• petfood usually refers to commercially prepared food such as canned, semimoist, dry, kibbled, biscuits, and loaves or butcher’s scraps provided for dogs and cats in various forms.

  • convenience p. commercial pet foods.
  • dry p. the meal or biscuit type dog and cat foods that contain approximately 10% water. Economical, easily transported and stored; in many countries, this is the most commonly used form of mass-produced pet food.
  • expanded p. a form of dry pet food production in which the ingredients are cooked, then forced through a die under pressure, resulting in expansion.
  • generic p. commercially prepared pet foods without a brand name; usually of low cost and possibly of poor quality. High concentrations of calcium in generic dog foods have reportedly been the cause of copper, zinc, and iodine deficiency in a syndrome called generic dog food disease.

• premium p. a commercially prepared dog or cat food, sold through selected outlets and at higher prices than other pet foods, suggesting a superior quality. The formula is generally constant, irrespective of variations in cost and availability of ingredients.

• private label p. a product marketed under the label of the retailer; the house brand.

• puréed p. foods of a gruel-like consistency; designed for enteral feeding.

  • variable formula p. manufactured pet foods in which the ingredients vary according to their availability and cost; the type most commonly marketed.

• pethidine [peth′ľ-din] meperidine.

• petiole [pet′e-ōl] a stem, stalk or pedicle.

  • epiglottic p. the pointed caudal end of the epiglottic cartilage, attached to the thyroid cartilage. Called also petiolus epiglotticus.

• Petit Basset Griffon Vendéen [p -te′] a short-legged, compact scent hound with a slightly elongated body and head, pendulous, narrow ears, and straight tail. The coat is long and harsh and can be any solid color, bicolored, or tricolored. In the UK, called the Basset Griffon Vendeen (Petit). Called also Grand Basset Griffon Vendeen and PBGV.

• petit mal [p -te′ mahl] a relatively mild seizure contrasting with grand mal, a major seizure. Occurs in humans where the patient loses consciousness only momentarily, and there are few motor signs. Petit mal seizures in animals are more correctly referred to as partial, or focal seizures. See also focal seizure.

• petits poussins chickens approximately 1.5 lb (650–700 g) in weight, and fattened on a special diet. A gourmet delicacy.

• Petiveria alliacea South American plant in the family Phytolaccaceae; causes digestive disturbance, muscular atrophy, and glomerulonephritis. Contains an unidentified garlic-odored, carbamate-like toxin. Called also anamu.

• Petri dish [pe′tre] a shallow, circular, glass or disposable plastic dish used to grow bacteria on solid media such as agar.

• Petriellidium boydii see Scedosporium apiospermum.

• pétrissage [pa″trľ-sahzh′] [F.] a technique of deep muscle massage using kneading, rolling or squeezing movements. The purpose is to free adhesions and improve local circulation.

• petrolatum [pet″ro-la′t m] a paraffin-like mixture of purified hydrocarbons obtained from petroleum; in most common usage, it is a nonpolar, hydrophobic, opalescent, soft wax used mostly for its water-repellant and lubricating properties as a base for ointments, protective dressings, and soothing applications to the skin. Also called petroleum jelly. Two types of liquid petrolatum are recognized, light and heavy. See also mineral oil.

  • liquid p. two types of liquid petrolatum are recognized, light and heavy; called ‘mineral oil’ in the US and ‘paraffin oil’ in other countries, it is used topically to soften or protect the skin and orally as a mild laxative or enteric lubricant, particularly in cats with hairballs and horses with colic.
  • white p. best known by its tradename, Vaseline®.

• petroleum jelly [p -tro′le- m] see petrolatum.

• petromastoid [pet″ro-mas′toid] 1. pertaining to the petrous portion of the temporal bone and its mastoid process. 2. otocranium (2).

• petrosal [p -tro′s l] pertaining to the pars petrosa, or petrous portion of the temporal bone.

• Petroselinum crispum cultivated plant in family Apiaceum; contains furanocoumarins that cause primary photosensitization. Called also P. hortense, P. sativum, parsley.

• petrositis [pet″ro-si′tis] inflammation of the pars petrosa or petrous portion of the temporal bone.

• petrosphenoid [pet″ro-sfe′noid] pertaining to the petrous portion of the temporal bone and to the sphenoid bone.

• petrosquamous [pet″ro-skwa′m s] pertaining to the petrous and squamous portions of the temporal bone.

• petrous [pet′r s] resembling rock or stone; stony.

  • p. bone the pars petrosa, or petrous portion of the temporal bone. See also Table 9.

• PETS Act Pets Evacuation and Transportation Standards Act 2006, subsequently codified and strengthened with the Post-Katrina Emergency Management Reform Act, ensures that state and local emergency preparedness operational plans address the needs of individuals with household pets and service animals in order to qualify for Federal funding.

• pexis [pek′sis] 1. the fixation of matter by a tissue. 2. surgical fixation, usually by suturing.

• -pexy word element. [Gr.] relationship to a surgical fixation.

• Peyer’s patches oval, elevated patches of closely packed lymph follicles in mucous and submucous layers of the small intestine. Called also aggregated lymphoid nodules.

  • continuous p. p. found in the terminal ileum in calves, lambs, piglets. Thought to be a primary site for B-cell generation; involute with age.

• peyote [pa-yo′ta] see Lophophora williamsii, hallucinogen.

• Peyronellaea glomerata a fungus isolated from hyperkeratoses on the ears of wild goats.

• Pezzer’s catheter a self-retaining urinary catheter with a bulbous extremity.

• PF-3 platelet factor-3.

• Pfeifferella a bacterial name no longer in use.

  • P. anatipestifer see Riemerella anatipestifer.
  • P. mallei see Burkholderia mallei.

• Pfiesteria [fe-ste′re- ] a genus of dinoflagellates associated with toxic algal blooms which cause death in fish.

• PFK phosphofructokinase.

• PFU plaque-forming unit; in virology, areas of cytopathic effect (CPE) in monolayer cell culture, under overlay conditions, initiated by adsorptionentry with a single infectious virus particle.

• PG prostaglandin.

• pg picogram.

• PGA pteroylglutamic (folic) acid.

• PGF_2α prostaglandin F_2α.

• PGI₂ prostacyclin.

• PGK phosphoglycerate kinase.

• PGM-2 phosphoglucomutase-2.

• pH the negative logarithm of the hydrogen ion concentration [H+]; a measure of the degree to which a solution is acidic or alkaline. An acid is a substance that can give up a hydrogen ion (H+); a base is a substance that can accept H+. The more acidic a solution, the greater the hydrogen ion concentration and the lower the pH; a pH of 7.0 indicates neutrality; a pH of less than 7 indicates acidity, and a pH of more than 7 indicates alkalinity.

  • p.–bicarbonate diagram an aid to the assessment of an acid–base problem; expresses the relationship between bicarbonate ions and the pH of the plasma.
  • blood p. normal blood pH varies a little between species but is of the order of 7.32 to 7.5. See also acid-base balance, acidosis, alkalosis.
  • p. partition the partition that occurs in the degree of ionization of electrolytes, including soluble drugs, about semipermeable membranes depending on the pH of the medium.
  • skin p. in haired mammals, the pH of skin is usually acidic. In dogs it is from 5.5 to 7.2; in cats from 5.6 to 7.4; in cattle from 5.4 to 5.75; and in the horse from 4.8 to 6.8.

• Ph. Eur. European Pharmacopoeia.

• PHA phytohemagglutinin, a plant lectin found primarily in certain beans.

• phacitis [f -si′tis] inflammation of or about the crystalline lens of the eye.

• phac(o)- word element. [Gr.] relationship to the lens.

• phacoanaphylaxis [fak″o-an″ -f -lak′sis] hypersensitivity to protein of the crystalline lens of the eye, induced by escape of lens material through the lens capsule. See lens-induced uveitis.

• phacocele [fak′o-sēl] crystalline lens dislocation or herniation.

• phacocystectomy [fak″o-sis-tek′t -me] excision of part of the lens capsule for cataract; capsulotomy.

• phacocystitis [fak″o-sis-ti′tis] inflammation about the capsule of the crystalline lens.

• phacodonesis [fak″o-do-nes′ s] tremulousness of the lens on movement of the eye, pathognomonic for lens subluxation. See also iridodonesis.

• phacoemulsification [fak″o-e-mul″sľ-fľ-ka′sh n] a technique of cataract extraction, utilizing high-frequency ultrasonic vibrations to fragment the lens combined with controlled irrigation to maintain normal pressure in the anterior chamber, and aspiration of the lens fragments and irrigating fluid. Called also phacofragmentation.

• phacoerysis [fak″o- -re′sis] surgical removal of the cataractous lens by aspiration; largely replaced by phacoemulsification.

• phacofragmentation [fak″o-frag-m n-ta′shun] see phacoemulsification.

• phacoid [fak′oid] shaped like a lens.

• phacoiditis [fak″oi-di′tis] phacitis.

• phacolysis [f -kol′ľ-sis] disruption of the lens as a cataract becomes hypermature.

• phacomalacia [fak″o-m -la′sh] softening of the crystalline lens; a soft cataract, that is, one without a hard nucleus.

• phacometachoresis [fak″o-met″ -ko-re′sis] displacement of the crystalline lens.

• phacosclerosis [fak″o-skl -ro′sis] hardening of the crystalline lens; more commonly called nuclear sclerosis.

• phacoscope [fak′o-skōp] an instrument for viewing accommodative changes of the crystalline lens.

• Phaenicia [fe-nish′ ] see Lucilia.

• phae(o)- for words beginning thus see words beginning phe(o)-.

• phaeochromoblast [fe″o-kro′mo-blast] pheochromoblast.

• phaeochromocytoma [fe″o-kro″mo-si-to′m ] see pheochromocytoma.

• phaeohyphomycosis [fe″o-hi″fo-mi-ko′sis] opportunistic infections caused by the pigmented (dematiaceous) fungi, including Alternaria, Aureobasidium, Bipolaris, Cladophialophora, Curvularia, Drechslera, Exophiala, Exserohilum rostratum, Moniliella, and Phialophora, Wangiella spp. subcutaneous p. subcutaneous nodules containing yellow-brown fungal hyphae, and that may ulcerate and produce a sinus tract. Can cause a mycetoma if the lesions develop to a granuloma.

• phage [fāj] see bacteriophage.

  • p. type a group of bacteria within a species with the same susceptibility to a panel of bacteriophages; called also lysotype and phagotype.
  • p. typing characterization of bacteria, extending to strain differences, by demonstration of susceptibility to one or more (a panel) bacteriophages; widely applied to staphylococci, salmonellae, and some other species for epidemiological purposes.

• phagedena [faj″ -de′n] rapidly spreading and sloughing ulceration.

• phagedenic [faj″ -den′ik] pertaining to or emanating from phagedena.

  P-39.

  

  Phagocytosis

• -phagia, -phagy word element. [Gr.] relationship to eating, swallowing.

• phag(o)- word element. [Gr.] relationship to eating, ingestion.

• phagocyte [fa′go-sīt] any cell that ingests microorganisms or other cells and foreign particles.

• phagocytic [fa″go-sit′ik] pertaining to phagocytes.

  • p. deficiency usually related to a deficiency in opsonization or a failure of intracellular killing.
  • p. system see reticuloendothelial system.
  • p. vacuole see phagosome.

• phagocytin a bactericidal substance from neutrophilic leukocytes.

• phagocytize the act of phagocytosis. Phagocytose.

• phagocytoblast a cell giving rise to phagocytes.

• phagocytolysis destruction of phagocytes.

• phagocytose [fa″go-si′tōs] to envelop and destroy bacteria and other foreign material; phagocytize.

• phagocytosis [fa″go-si-to′sis] the engulfing of microorganisms, other cells or foreign particles by phagocytes.

• phagodynamometer [fa″go-di″n -mom′-t r] an apparatus for measuring the force exerted in chewing food.

• phagokaryosis [fa″go-ka-re-o′sis] phagocytosis affected by the cell nucleus.

• phagolysosome [fag″o-li′so-sōm] a phagocytosed substance is initially engulfed by a phagocytic cell by creating an invagination of a small region of the cell membrane that subsequently is pinched off to form a phagocytic vesicle. This vesicle then fuses with a lysosome to form a phagolysosome within which the lysosomal enzymes are released, and other killing mechanisms are activated, and the phagocytosed material is degraded.

• phagosome [fag′o-sōm] a membrane-bound vesicle in a phagocyte containing the phagocytized material. Called also a phagocytic vacuole.

• phagotype [fag′o-tīp] phage type.

• phak(o)- for words beginning thus see words beginning phac(o)-.

• phacotoxic [fak′o-tok″sik] type of uveitis associated with cataractous degeneration.

• phalangeal [f -lan′je- l] pertaining to a phalanx.

• phalangectomy [fal″ n-jek′t -me] excision of a phalanx.

• phalanger marsupials from the family Phalangeridae; see possum.

• phalanges [f -lan′jēz] plural of phalanx.

  • congenital reduced p. incomplete limbs in newborn animals; they may have an inherited defect or may have been exposed to a noxious environmental influence such as irradiation in early pregnancy.

• Phalangida see harvestmen.

• phalangitis [fal″ n-ji′tis] inflammation of one or more phalanges.

• phalanx [fa′lanks] pl. phalanges [Gr.] any of the principal bones of a digit. Commonly referred to as P1, P2, and P3, being numbered from proximal to distal. Called also proximal, middle, and distal. In horses, called also long pastern, short pastern, and coffin bones. In some aquatic animals (some turtles and Cetacea) the number of phalanges is often increased (hyperphalangy) in some digits. The feet of birds have digits I, II, III, and IV with 2, 3, 4, and 5 phalanges, respectively. See also Table 9.

  • inherited reduced p. a congenital absence of the first two phalanges on all limbs. The hoof and third phalanx are attached by skin. An inherited defect in cattle.

• Phalaris [f -lar′is] a grass genus of the Poaceae family containing some of the best temperate pasture grasses that can, on occasion, be poisonous. Cause two kinds of poisoning: (1) acute heart failure and sudden death in sheep—caused by P. aquatica, P. arundinacea, and Rhompa grass (a hybrid variety), and in horses caused by P. coerulescens (blue canary grass, sonolgrass) and P. paradoxa (paradoxa grass, hood canary grass, paradoxical canary grass, gnawed canary grass), (2) incoordination with tremor and head nodding, finally recumbency, and convulsions (called also phalaris staggers and caused by all species). New cases occur for many weeks after removal from the pasture. There is a characteristic gray-green discoloration of the brainstem and midbrain. Includes P. aquatica (P. tuberosa, Australian phalaris, bulbous canary grass, Toowoomba canary grass), P. arundinacea (reed canary grass), P. minor (littleseed canary grass), P. angusta, P. brachystachys, P. canariensis, P. caroliniana, and Rhompa grass, a hybrid form. Toxins include β-carbolines, tryptamine, and indole alkaloids.

• phalaris [f -lar′is] plants in the genus Phalaris.

  • Australian p.P. aquatica.

• phalaris staggers [f -lar′is] see Phalaris.

• Phalene a small, drop-eared dog, usually included as a variant of the Papillon, but in some countries is regarded as a separate variety.

• phallectomy [f -lek′t -me] amputation of the penis.

• phallic [fal′ik] pertaining to the penis.

  • p. body see phallic body.

• phallitis [f -li′tis] penitis.

• phallocampsis [fal″o-cam′sis] curvature of the penis during erection.

• phallocrypsis [fal″o-krip′sis] retraction of the penis.

• phalloidin [f -loi′dēn] a bicyclic hexapeptide toxin from the mushroom Amanita phalloides, which causes fatal liver necrosis. Although phalloidin can damage liver cells, it is not absorbed and thus is thought to be responsible for damage to enterocytes that causes the initial gastrointestinal tract signs of nausea, vomiting, and diarrhea. The fatal liver damage associated with ingestion of A. phalloides is attributable to the amatoxins it also produces.

• phalloncus [f -long′k s] a pathological swelling of the penis.

• phallopexy [fal″o-pek′se] surgical fixation of the penis, e.g., as performed to create a teaser bull, or to correct a chronically prolapsed penis in a horse or dog.

• phallus [fal′ s] the penis.

• phantom [an′t m] 1. a model of the body or of a specific part thereof. 2. a device for simulating the in vivo effect of radiation on tissues.

  • p. mare a dummy of a mare used to collect semen for artificial insemination. A padded, hollow device about the height and width that would suit the stallion to be used. Excellent for collecting from an insecure or lame stallion.
  • p. parturition see false pregnancy.
  • p. pregnancy see false pregnancy.
  • imaging p. a specifically manufactured object used for testing and tuning the performance of an imaging system.
  • ultrasound p. a homemade or purchased object for practicing ultrasound examinations and interventional procedures such as fine needle aspiration.

• phar., pharm. abbreviations for pharmacy, pharmaceutical, or pharmacopeia.

• Pharaoh hound a medium-sized, lean, graceful dog distinguished by its very short, fine orange-red coat, amber eyes, broad-based, erect ears, and a long, thin tail. The national dog of Malta.

• pharmaceutical [fahr″m -soo′tľ-k l] 1. pertaining to pharmacy or medicinal drugs. 2. a medicinal drug.

  • p. incompatibility substances that react chemically with each other, e.g., acids and alkalis, and cannot both be included in the same formulation.
  • p. industry the industry responsible for the research, development, and manufacture of pharmaceuticals.

• pharmaceutics [fahr″m -soo′tiks] pharmaceutical preparations; medications, medicinal drugs.

• pharmacist [fahr′m -sist] an individual who is licensed to prepare, compound, and dispense drugs upon written order (prescription) from a licensed veterinary, medical, or dental practitioner. A pharmacist is a health care professional who collaborates and consults with and sometimes advises the licensed practitioner concerning drugs.

• pharmac(o)- word element. [Gr.] relationship to a drug or medicine.

• pharmacodiagnosis [fahr″m -ko-di″ g-no′sis] use of drugs in diagnosis, such as phentolamine in the diagnosis of pheochromocytoma; at its most basic is ‘response to treatment’, where a diagnosis is made retrospectively based on the patient’s response to empirical treatment.

• pharmacodynamics [fahr″m -ko-di-nam′iks] the study of the mechanisms of action of drugs, including the primary effect(s) and other biochemical and physiological effects (side effects, whether or not they are considered adverse). Whereas pharmacokinetics is concerned with the movement of a drug through the body (what the body does to the drug), pharmacodynamics is concerned with what the drug does to the body.

• pharmacoepidemiology [fahr″m -ko-ep″ľ-de″me-ol′ -je] the study of the utilization and effects of drugs in patient populations.

• pharmacogenetics [fahr″m -ko-j -net′iks] the study of the relationship between genetic factors and the nature of responses to drugs. An example in dogs is the susceptibility of Collies and related breeds to the adverse effects of ivermectin. See MDR1 gene.

• pharmacognosy [fahr″m -kog′n -se] the branch of pharmacology dealing with natural drugs and their constituents.

• pharmacokinetics [fahr″m -ko-kľ-net′iks] the study of the movement of drugs through the body, including the processes of absorption, distribution, localization in tissues, biotransformation and excretion. Whereas pharmacodynamics is concerned with the mechanism(s) of action, or what the drug does to the body, pharmacokinetics is concerned with what the body does to the drug.

• pharmacologic [fahr″m -k -loj′ik] pharmacological.

• pharmacological [fahr″m -k -loj′ik] pertaining to pharmacology.

  • p. antagonism the relationship between drugs in which an antagonist inhibits the activity of an agonist by reacting with the receptor or other part of the effector mechanism. The antagonist has no other pharmacological function. It may be a competitive or noncompetitive antagonist.

• pharmacologist [fahr″m -kol′ -jist] a specialist in pharmacology.

• pharmacology [fahr″m -kol′ -je] the science that deals with the origin, nature, chemistry, effects, and uses of drugs; it includes pharmacognosy, pharmacokinetics, pharmacodynamics, pharmacotherapeutics, and toxicology.

• pharmacopeia [fahr″m -ko-pe′] an authoritative treatise on drugs and their preparations. Outside the Us, spelled pharmacopoeia. See British Pharmacopoeia, European Pharmacopoeia, International Pharmacopoeia, United States Pharmacopeia.

• pharmacophore [fahr′m -ko-for″] the group of atoms in the molecule of a drug responsible for the drug’s action.

• pharmacopoeia [fahr″m -ko-pe′] British spelling of pharmacopeia.

• pharmacotherapy [fahr″m -ko-ther′ -pe] treatment of disease with pharmaceutical agents or medicines.

• pharmacovigilance [fahr″m -ko-vij′ľ-l ns] the surveillance of a drug’s performance, particularly of adverse drug reactions (ADRs), after it has been released onto the market; also known simply as drug safety.

• pharmacy [fahr′m -se] 1. the branch of the health sciences dealing with the preparation, dispensing, and proper utilization of drugs. 2. a place where drugs are stored, compounded or dispensed.

• pharyngeal [f -rin′je- l] pertaining to the pharynx.

  • p. abscess an abscess in the wall of the pharynx causing painful and difficult swallowing, pain on palpation, cough, and if sufficiently large, the signs of pharyngeal obstruction.
  • p. cyst subepiglottic cysts (remnants of thyroglosssal duct) and cysts on dorsum of pharynx and soft palate (remnants of craniopharyngeal ducts) may cause obstruction of the pharynx in the horse.
  • p. diverticulum a small, 3–4 cm, midline diverticulum dorsal to the pharyngeal opening of the esophagus. Found only in pigs. It can become impacted with dried food and cause dysphagia. It also needs to be circumvented when passing an esophageal-gastric cannula for artificial feeding of neonatal piglets.
  • p. dysphagia see oropharyngeal dysphagia.
  • p. hypophysis cyst a distended remnant of the pharyngeal anlage of the pituitary gland. It may protrude into the nasopharynx and obstruct respiration.
  • p. lymphadenopathy enlargement of the pharyngeal lymph nodes, due to abscess, neoplasia, e.g., bovine viral leukosis, or hyperplasia and granuloma in chronic pharyngitis, is a possible cause of pharyngeal obstruction.
  • p. lymphoid hyperplasia there is hyperplasia of lymphoid follicles evident on the mucosae of the nasopharynx of horses. The lesions can be observed via a fiberoptiscope, are more commonly found in young horses and resolve with age. No clear association with reduced performance or respiratory disease.
  • p. neoplasia a high incidence of squamous cell carcinoma in the mouth, pharynx and rumen is recorded in several countries, some associated with grazing on bracken. Chronic dysphagia and tympany result.
  • p. obstruction characterized by noisy breathing, difficult swallowing, coughing and the coughing up of food. In dogs and cats pawing at the mouth is usual. There is no regurgitation through the nostrils. Manual or endoscopic examination of the interior of the pharynx is necessary. A common cause is foreign body impaction. See also throat abscess (1), pharyngeal cyst and pharyngeal lymphadenopathy (above), pharyngeal polyp (below), and impaction of the pharyngeal diverticulum (above) in pigs.
  • p. paralysis presents a syndrome similar to pharyngeal obstruction with coughing, inability to swallow, but with no signs of pain or respiratory obstruction. See also cud dropping. A feature of acute doxycycline poisoning in calves.
  • p. phlegmon a peracute peripharyngitis, most commonly of cattle, characterized by profound toxemia, respiratory distress, swelling and pain of the throat area, painful cough, and high fever. Fusobacterium necrophorum is usually present in the lesion. Called also intermandibular cellulitis.
  • p. polyp a fibrous or mucoid, usually pedunculated mass that causes intermittent pharyngeal obstruction.
  • p. pouch one of the paired bilateral outpockets of the embryonic pharynx located opposite external branchial clefts and separated from each other by the developing visceral or branchial arches.
  • p. reflex gag reflex.
  • p. swab nasopharyngeal swab.

• pharyngectomy [far″in-jek′t -me] excision of part of the pharynx.

• pharyngemphraxis obstruction of the pharynx.

• pharyngismus [far″in-jiz′m s] muscular spasm of the pharynx.

• pharyngitis [far″in-ji′tis] inflammation of the pharynx, characterized by coughing, painful swallowing, and lack of appetite. The throat is sore on palpation. In severe cases, food and saliva may be regurgitated through the nostrils.

  • chronic equine p. is relatively common after viral infections. There is persistent coughing and moderate dyspnea on exercise. Training cannot be done. Endoscopic examination shows lymphoid infiltration and follicular hyperplasia.
  • equine lymphoreticular p. see chronic equine pharyngitis (above).

• plasma cell p. see feline lymphocytic-plasmacytic gingivitis–stomatitis.

• pharyng(o)- word element. [Gr.] relationship to the pharynx.

• Pharyngobolus a genus of parasitic flies in the family Oestridae. The larval stages resemble those of Oestrus ovis.

  • P. africanus found in the pharynx of African elephants. Called also elephant throat bot fly.

• pharyngocele [f -ring′go-sēl] a herniation or cystic deformity of the pharynx.

• pharyngoesophageal [f -ring″go--sof′-je″ l] pertaining to the pharynx and esophagus.

• pharyngoglossal [f -ring″go-glos′ l] pertaining to the pharynx and tongue.

• pharyngogram a radiograph of the pharynx aided by the administration of contrast agent.

• pharyngokeratosis [f -ring″go-ker″ -to′sis] keratosis of the pharynx.

• pharyngolaryngitis [f -ring″go-lar″in-ji′tis] inflammation of the pharynx and larynx.

• pharyngomycosis [f -ring″go-mi-ko′sis] any fungal infection of the pharynx.

• pharyngonasal [f -ring″go-na′s l] pertaining to the pharynx and nose.

• pharyngoparalysis [f -ring″go-p -ral′ľ-sis] paralysis of the pharyngeal muscles; pharyngoplegia.

• pharyngoperistole see pharyngostenosis.

• pharyngoplasty [f -ring′go-plas″te] plastic repair of the pharynx.

• pharyngoplegia [f -ring″go-ple′j] pharyngoparalysis.

• pharyngorhinitis [f -ring″go-ri-ni′tis] inflammation of the nasopharynx.

• pharyngorrhea [f -ring″go-re′] mucous discharge from the pharynx.

• pharyngoscope [f -ring′go-skōp] an endoscopic instrument for examining the pharynx.

• pharyngoscopy [far″ing-gos′k -pe] direct visual examination of the pharynx, usually with the aid of an endoscope.

• pharyngospasm [f -ring′go-spaz″ m] spasm of the pharyngeal muscles.

• pharyngostenosis [f -ring″go-st -no′sis] narrowing of the pharynx; pharyngoperistole.

• pharyngostomy [far″ing-gos′t -me] creation of an artificial opening into the pharynx.

  • p. intubation an opening created through the skin of the neck or throat can be used to insert (1) an esophagostomy tube for feeding when the oral cavity must be bypassed following injury or surgery or (2) an endotracheal tube.

• pharyngotomy [far″ing-got′ -me] incision of the pharynx.

• pharyngotympanic tube [f -ring″go-tim-pan′ik] the narrow channel that connects the middle ear with the nasopharynx; called also auditory tube, eustachian tube. The tube serves to equalize pressure on either side of the tympanic membrane (eardrum). Called also tuba auditiva.

• pharynx [far′inks] the throat; the musculomembranous crossroads of the digestive and respiratory systems, found behind the nasal cavities and mouth, and rostral to the larynx and esophagus. The pharynx includes many individual structures and may be divided into three parts: the nasopharynx (above), oropharynx (below) and laryngopharynx (behind). The nasopharynx, connected with the nasal cavities, provides a passage for air during breathing; it also contains the openings of the auditory tubes through which air enters the middle ear. The oropharynx and laryngopharynx provide passageways for both air and food. The pharynx also functions as a resonating organ in vocalization. The pharynx is subdivided by the soft palate. In swallowing, the palate lifts up, closing off the nasopharynx as food passes from the mouth to the esophagus.

  P-40.

  

  Examining the pharynx in a dog

• phascogales (Phascogale spp.) small, carnivorous Australian marsupials, consisting of three species. Like their close relatives, the antechinus, almost all males die after their first breeding season.

• phase [fāz] 1. one of the aspects or stages through which a varying entity may pass. 2. In physical chemistry, a component that is homogeneous of itself, bounded by an interface, and mechanically separable from other phases of the system.

  • continuous p. in a heterogeneous system, the component in which the disperse phase is distributed, corresponding to the solvent in a true solution.
  • disperse p. the discontinuous portion of a heterogeneous system, corresponding to the solute in a true solution.
  • p. plate a critical component of a phase microscope.

• phase variation alternate expression of two or more genes in bacteria, effected by a genetic rearrangement or by insertion or deletion of one or more bases. One example occurs in Salmonella enables two alternative forms of the flagellin gene, H¹ and H², are expressed.

• phaseolunatin [fa″se-o-loo′n -tin] a cyanogenetic glycoside found in Phaseolus lunatus, the Java bean.

• Phaseolus [fa″ze-o′l s] a genus of bean plants in the family Fabaceae; contain a number of phytotoxins including phaseolus hemolytic agent, lunatin, a cyanogenetic glycoside, and a hemagglutinating lectin that causes vomiting, diarrhea. Includes garden kidney beans (P. vulgaris—French beans, P. coccineus—scarlet runner climbing bean) and crop beans such as Lima and Java beans (P. lunatus).

• phaseolus hemolytic agent [fa″ze-o′l s] hemolytic agent found in members of the genus Phaseolus.

• Phasianus see pheasant.

• phasmid either of the two caudal chemoreceptors occurring in certain nematodes (Phasmidia or Secernentea).

• Phe phenylalanine.

• pheasant gallinaceous birds that are members of the family Phasianidae, which also includes partridge, quail, and peafowls. They are ground feeders and tree roosters, with profuse, brightly colored plumage and a long tail and are a popular game bird. There are very many species, the best known being Phasianus colchicus, the common ringneck pheasant. Others include blue-eared pheasant (Crossoptilon auritum), golden pheasant (Chrysolophus pictus), Reeves pheasant (Syrmaticus reevesii), silver pheasant (Lophura nycthemera).

• pheasant’s eye Adonisannua, A. microcarpa. Includes red-flowering summer p’s e. A. aestivalis, yellow p’s. e. A. vernalis.

• phemerol [fe′m r-ol] see benzethonium chloride.

• phenacetin [f -nas′ -tin] a para-aminophenol-derivative analgesic, similar to acetanilide. Its toxicity is much higher than that of the salicylates and other analgesics, especially for cats, so it is not used much in veterinary medicine. Called also acetophenetidin.

• phenamidine isethionate an aromatic diamidine used as an antiprotozoal agent, particularly in the treatment of infections by Babesia, Leishmania and Pneumocystis spp.

• phenanthrene [fě-nan′thrēn] a colorless, crystalline hydrocarbon used in industry. Has caused photosensitization.

• phenanthridium, phenanthridine a group of chemotherapeutic agents used in the treatment of trypanosomiasis. Includes isometamidium, homidium, pyrithidium (Prothidium), and quinapyramine.

• phenarsonic acid pharmaceutical aliphatic organic arsenical; see also organic arsenical.

• phenazone [fen′ -zōn] INN (International Nonproprietary Name) and BAN (British Approved Name) for antipyrine, an analgesic and antipyretic agent.

• phenazopyridine [fen″ -zo-pir′ľ-dēn] an azo dye, used as a urinary analgesic and antiseptic in humans. Causes hemolytic anemia and hepatic injury in cats.

• phencyclidine [fen-si′klľ-dēn] an illegal street drug that was previously used as a dissociative agent in nonhuman primates. Known as ‘angel dust’.

• phenelzine [fen′ l-zēn] a monoamine oxidase inhibitor, used as an antidepressant.

• phenethicillin a semisynthetic acid-resistant penicillin, administered orally. It is little used in veterinary practice and is not approved for use in the US.

• phenethylamine [f n-ir′ -mēn] a toxic substance in North American mistletoe, Phoradendron villosum.

• phenidone 1-phenyl-3-pyrazolidone; a developer used with hydroquinone in the development of x-ray film.

• pheniprazine an irreversible monoamine oxidase inhibitors previously used as an antidepressant but withdrawn because of its toxicity.

• pheniramine a histamine type 2 (H₂) receptor antagonist (antihistamine) with anticholinergic and sedative properties.

• phenobarbital [fe″no-bahr′bľ-t l] a long-acting barbiturate; widely used as an anticonvulsant and sedative.

• phenobarbitone [fe″no-bahr′bľ-tōn] phenobarbital.

• phenocopy [fe′no-kop″e] 1. an environmentally induced phenotype mimicking one usually produced by a specific genotype. 2. an individual exhibiting such a phenotype; the simulated trait in a phenocopy. 3. experimentally produced phenocopies have been created in unfertilized rabbit eggs by the microinjection of the nuclei of embryonic rabbit cells.

• phenodeviant [fe″no-de′ve- nt] an individual whose phenotype differs significantly from that of the typical phenotype in the population.

• phenogroup [fe″no-groop] group of red cell antigens in a blood group inherited by offspring from parents as a complex.

• phenol [fe′nol] 1. an extremely poisonous compound obtained by distillation of coal tar or produced synthetically; used as a disinfectant and used extensively as a wood preservative. Called also carbolic acid. 2. any organic compound containing one or more hydroxyl groups attached to an aromatic or carbon ring.

  • chlorinated p. see biphenyl.
  • plant p. includes gossypol, tannins.
  • p. poisoning animals can be exposed to phenol by skin contact with floors and housing that have been treated with the disinfectant, or other phenol-rich substance such as lignite pitch. Causes local tissue necrosis and hepatic injury. Cats are particularly susceptible.
  • p. red see phenolsulfonphthalein.

• phenolphthalein [fe″nol-thal′ēn] 1. an acid–base indicator dye; it is colorless below pH 8.5, but turns red above pH 9.0. 2. in monogastric animals, a cathartic administered orally, usually with a bulk laxative such as agar. When ingested by ruminants causes the urine to change color to red on exposure to air.

• phenolsulfonphthalein (PSP) [fe″nol-sul″fon-thal′ēn] an acid–base indicator dye.

  • p. (PSP) clearance test see phenolsulfonphthalein (PSP) clearance test.

• phenoltetrachlorphthalein a dye once used intravenously as a liver function test.

• phenomenon pl. phenomena [Gr.] any observable occurrence or fact of which the cause is not immediately evident. In veterinary science usually relates to laboratory findings but can relate to clinical signs. Typical examples are Berry–Dedrick phenomenon, CAMP phenomenon, Koch phenomenon, rickettsial interference phenomenon, satellitism, swarming (1).

• phenacemide [f -nas′ -mīd] an anticonvulsant drug.

• phenothiazine the first broad-spectrum veterinary anthelmintic and the market leader in all agricultural animals for many years. Now largely superseded by more efficient compounds. Used now only in horses. Not recommended for use in pregnant mares because of the risk of causing abortion. Its principal use is in mixtures with piperazine and in small daily doses to inhibit egg-laying by resident worms. It must be supported by regular dosing at full dose rates. The name is also used to denote a group of major tranquilizers resembling phenothiazine in molecular structure.

  P-41.

  

  Polypay lamb with the phenotype of Border disease (hairy shaker disease)

• phenotype [fe′no-tīp] 1. the outward appearance of the animal in all of its anatomical, physiological, and behavioral characteristics as dictated by the genetic and environmental influences in its environment; in contradistinction to genotype in which only the inherited factors are taken into account. 2. an individual exhibiting a certain phenotype; a trait expressed in a phenotype.

• phenoxyacids [f -nok″se-as′idz] phenoxy derivatives of fatty acids used as herbicides; are largely innocuous to animals. They may make poisonous plants temporarily more palatable and increase their content of cyanide or nitrate. The common members of the group are 2,4-D, 2,4,5-T, MCPA, 2,4-DB, MCPB, and fenoprop. Myotonia can be seen in dogs poisoned with phenoxy herbicides.

• phenoxybenzamine [f -nok″se-ben′z -mēn] a long-acting α-adrenergic antagonist; used as a vasodilator, as a relaxant in functional urethral obstruction associated with urinary retention (‘reflex’ or ‘upper motor neuron’ bladder), and for relief of urethral spasm in cats with cystitis or mechanical urethral obstruction (‘blocked cat’). Has proved useful in some cases of chronic diarrhea in horses.

• phenoxymethylpenicillin [f -nok″se-meth″ l-pen″ľ-sil′in] see phenoxymethyl penicillin.

• phenpropionate [f n-pro′pe- -nāt″] United States Adopted Name (USAN) contraction for 3-phenylpropionate, an ester used in the manufacture of certain medicinal drugs.

• phensuximide [f n-suk′sľ-mīd] an anticonvulsant. See succinimides.

• phentolacin an indandione derivative once used as an anticoagulant rodenticide.

• phentolamine [f n-tol′ -mēn] a potent α-adrenergic blocking agent; it blocks the hypertensive action of epinephrine (adrenaline) and norepinephrine (noradrenaline) and most responses of smooth muscles that involve α-adrenergic cell receptors. Its hydrochloride and mesylate salts are used in the diagnosis of hypertension due to pheochromocytoma.

• phenyl the monovalent radical, C₆H₅.

  • p. salicylate a salicylic acid ester used as an analgesic and antiseptic.

• phenylalanine (Phe) [fen″ l-al′ -nēn] a naturally occurring amino acid essential for optimal growth in young animals and for nitrogen equilibrium in adults.

  • p. deaminase test a biochemical test used for the identification of bacteria, based on the formation of phenylpyruvic acid and ammonia from phenylalanine.

• phenylbutazone (PBZ) [fen″ l-bu′t -zōn] a nonsteroidal anti-inflammatory drug (NSAID) widely used to treat inflammation involving the musculoskeletal system in horses. In the US its extra-label use is restricted in all food animals and prohibited in dairy cows. Its use in dogs has been superseded by safer NSAIDs such as carprofen, meloxicam, and firocoxib. It is often called by its common name, ‘bute’, and occasionally still by its early tradename, Butazolidin (BTZ).

• phenylephrine [fen″ l-ef′rin] adrenergic agonist or sympathomimetic used as the hydrochloride salt as a nasal decongestant and in ophthalmology to induce mydriasis.

• phenylhydrazine [fen″ l-hi′dr -zēn] a chemical reagent for detection of reducing substances such as sugars, ketones and aldehydes.

• phenylmercuric [fen″ l-m r-ku′rik] denoting a compound containing the radical C₆H₅Hg−, forming various antiseptic, antibacterial, and fungicidal salts; compounds of the acetate and nitrate salts are used as bacteriostats, and the former is also used as a herbicide.

  • p. acetate used as a bacteriostatic preservative in pharmaceutical preparations, as a topical fungistatic agent, and as a herbicide.
  • p. chloride used as a bacteriostat in pharmaceuticals.
  • p. nitrate used as a antibacterial preservative in pharmaceutical preparations, and as a topical antiseptic.

• phenylpropanolamine [fen″ l-pro″p-nol′ -mēn] an α-adrenergic agonist used in the treatment of urethral sphincter incompetence in bitches.

• phenylpyruvic acid [fen″ l-pi-roo′vik] an intermediate product of the metabolism of phenylalanine in the body.

• phenylurea a chemical compound on which relatively nontoxic herbicides are based. Very high intakes of these cause loss of appetite and weight and weakness of the hindquarters.

• phenytoin [fen′ľ-toin″] an anticonvulsant used as the sodium salt. Used infrequently in animals due to its short half-life in dogs and cats but used in humans to control seizures and status epilepticus; also used for the control of cardiac arrhythmias, especially those caused by digitalis intoxication. Formerly called diphenylhydantoin.

• pheo- a word element meaning brown, dun or dusky.

• pheochrome [fe′o-krōm] chromaffin.

• pheochromoblast [fe″o-kro′mo-blast] any of the embryonic structures that develop into chromaffin (pheochrome) cells.

• pheochromocyte [fe″o-kro′mo-sīt] a chromaffin cell.

• pheochromocytoma, phaeochromocytoma [fe″o-kro″mo-si-to′m ] a small chromaffin cell tumor, usually located in the adrenal medulla but occasionally occurring in chromaffin tissue of the sympathetic paraganglia. It occurs most often in dogs and cattle; in bulls it develops concurrently with C-cell tumors of the thyroid gland. Functional tumors secrete catecholamines, causing arteriolar sclerosis and medial hyperplasia and clinical signs of hypertension: tachycardia, edema, and cardiac hypertrophy.

• pheomelanin [fe″o-mel′ -nin] yellow to red-brown pigment produced by melanocytes. See also eumelanin.

• pheomelanosome [fe″o-mel′ -no-som] brown-colored melanosome producing pheomelanin.

• pheresis [f -re′sis] any procedure in which blood is withdrawn from a donor, a portion (plasma, leukocytes, etc.) is separated and retained, and the remainder is retransfused into the donor. It includes plasmapheresis, leukapheresis, etc.

• pheromonatherapy [fer′o-mōn-o-ther′ -pe] the use of pheromones in the treatment of behavioral disorders of dogs and cats. See also pheromone.

• pheromone [fer′o-mōn] a substance secreted to the outside of the body and perceived (as by smell) by other individuals of the same species, releasing specific behavior in the percipient. Feline and canine pheromone products are marketed commercially for the management of inappropriate urination (spraying), anxiety, and aggression.

• phi [fi] the 21st letter of the Greek alphabet, Φ or ϕ.

• phialide [fi′ -līd] an open-ended, tubular or flask-like conidiophore that produces multiple chains of phialoconidia. Seen in Aspergillus and Penicillium spp.

• phialoconidium [fi″ -lo-k-nid′e- m] pl. phialoconidia a conidium that develops from a phialide.

• Phialophora [fi″ -lof′-r] a genus dematiaceous fungi in the phylum Ascomycota that are associated with phaeohyphomycosis and chromoblastomycosis.

• Philadelphia chromosome the result of a translocation between the long arms of chromosomes 9 and 22 and results in the juxtaposition of the sequences of the breakpoint cluster region on chromosome 22 with the c-ABL tyrosine kinase gene on chromosome 9. The 9;22 translocation is found in bone marrow cells of more than 95% of human patients with chronic myelogenous leukemia. Named for the city in which it was discovered.

• Philaemon grandidieri a leech that invades the dorsal lymph sac of New Guinea frogs.

• -philia word element. [Gr.] affinity for.

• Phillips technique a method of teat stripping of dairy cows before commencing milking. Aimed at reducing the rate of new quarter infections. The top of the teat is clamped off with one hand, and the teat is stripped with the other, preventing reflux of infected milk into the udder cistern.

• Philodendron plant genus in the family Araceae and popular house plants. Toxin is insoluble calcium oxalate raphide crystals. Causes stomatitis and suspected to cause renal damage in cats.

• Philometra genus of deep red-colored, large nematodes of the dracunculoid family Philometridae; found in the peritoneal cavity of fish. Numerous species.

• Philophthalmus a genus of flukes (digenetic nematodes) in the family Philophthalmidae.

  • P. gralli found in the conjunctival sacs of birds causing congestion and erosion of the conjunctiva. Called also oriental avian eye fluke.

• philtrum [fil′tr m] the junction between the left and right upper lips; not distinctive in many animal species. In some, such as dogs, the term also applies to the noticeable junction between the two sides of the nose pad.

• Philydrum languinosum Australian plant in the family Philydraceae; contains an unidentified toxin that causes diarrhea; called also woolly water lily.

• phimosis [fi-mo′sis] constriction of the orifice of the prepuce so that it cannot be drawn back over the glans or, conversely, that the penis cannot be extended beyond the prepuce.

• phlebangioma [fleb″an-je-o′m ] a venous aneurysm.

• phlebarteriectasia [fleb″ahr-tēr″e- k-ta′zh] general dilatation of veins and arteries.

• phlebectasia [fleb″ek-ta′zh ] dilatation of a vein or veins; a varicosity.

• phlebectomy [fl -bek′t -me] excision of a vein, or a segment of a vein.

• phlebedema [fleb″ed-e′m ] edema resulting from venous insufficiency.

• phlebemphraxis [fleb″ m-frak′sis] stoppage of a vein by a plug or clot.

• phlebismus [fleb″iz′m s] obstruction and consequent turgescence of veins.

• phlebitis [fl -bi′tis] inflammation of a vein. Phlebitis is not serious when the inflammation is located in a superficial vein since these veins are numerous enough to permit the flow of blood to be rechanneled, so that the inflamed vein is bypassed. When a deep vein is involved, however, phlebitis is potentially more dangerous. It can also have serious consequences if it leads to thromboembolism or metastatic infection. Phlebitis of the jugular vein, as a result of intravenous medication at this site, can lead to endocarditis and pulmonary infarcts. The common causes in animals are omphalophlebitis (inflammation of the umbilical veins) and injection phlebitis caused by the inadvertent injection of irritant substances or the prolonged use of intravenous catheters. The vein is swollen and painful, and the blood flow obstructed.

• phleb(o)- word element. [Gr.] relationship to a vein.

• phleboclysis [fl -bok′lľ-sis] injection of fluid into a vein; venoclysis. See also intravenous infusion.

• phlebogram [fleb′o-gram] 1. a radiograph of a vein filled with contrast medium. 2. a phlebographic or sphygmographic tracing of the venous pulse.

• phlebograph [fleb′o-graf] an instrument for recording the venous pulse.

• phlebography [fl -bog′r -fe] 1. radiography of a vein filled with contrast medium. 2. the graphic recording of the venous pulse. 3. a description of the veins.

• phlebolith [fleb′o-lith] a venous calculus or concretion.

• phlebolithiasis [fleb″o-lľ-thi′ -sis] the development of phleboliths.

• phlebomanometer [fleb″o-m -nom′-t r] an instrument for the direct measurement of venous blood pressure.

• phlebophlebostomy [fleb″o-fl -bos′t -me] operative anastomosis of one vein to another, as of the portal vein and inferior vena cava.

• phleboplasty [fleb′o-plas″te] plastic repair of a vein.

• phleborrhaphy [fl -bor′ -fe] suture of a vein.

• phleborrhexis [fleb″o-rek′sis] rupture of a vein.

• phlebosclerosis [fleb″o-skl -ro′sis] fibrous thickening of the walls of veins.

• phlebostasis [fl -bos′t -sis] 1. retardation of blood flow in veins. 2. temporary sequestration of a portion of blood from the general circulation by compressing the veins of an extremity.

• phlebothrombosis [fleb″o-throm-bo′sis] the development of venous thrombi in the absence of associated inflammation of the vessel wall, as opposed to thrombophlebitis, in which there are inflammatory changes in the vessel wall. See also venous thrombosis.

• Phlebotomus [fl -bot′-m s] a genus of biting flies, called sandflies, the females of which are blood-sucking. They are vectors of various human diseases, including kala-azar (P. argentipes, P. chinensis, P. martini, P. perniciosus), Carrion’s disease (P. noguchi, P. verrucarum, P. columbianum), cutaneous leishmaniasis (P. sergenti, P. papatasi, P. major, P. caucasicus), and phlebotomus or sandfly fever (P. papatasi, P. chinensis, P. mongolensis).

• phlebotomy [fl -bot′ -me] incision of a vein. See venisection.

• Phlebovirus [fleb′o-vi″r s] a genus in the family Bunyaviridae.

• phlegm [flem] viscid mucus excreted in abnormally large quantities from the respiratory tract.

• phlegmasia [fleg-ma′zh ] inflammation.

• phlegmon [fleg′mon] diffuse inflammation of the soft or connective tissue due to infection. See also cellulitis.

• throat p. see pharyngeal phlegmon.

• phlegmonous [fleg′m n- s] pertaining to or emanating from phlegmon.

• Phleum pratense [fle′ m] the old-fashioned but still popular pasture grass in the family Poaceae that can be infested with Claviceps purpurea and cause ergotism. Historically has been claimed to be a good hay for horses. Called also timothy grass.

• phlogistic [flo-jis′tik] inflammatory.

• phlog(o)- word element. [Gr.] relationship to inflammation.

• phlogogenic [flo″go-jen′ik] producing inflammation.

• phloridzin, phlorizin [flo-rid′zin] a dihydrochalcone extracted from the root bark of the apple tree. Thought at one time to be present in cherry, plum, and pear. Blocks the renal tubular reabsorption of glucose hence promoting the development of glycosuria.

• phlyctena [flik-te′n ] 1. a small blister made by a burn. 2. a small vesicle containing lymph seen on the conjunctiva in certain conditions.

• phlyctenoid [flik′t -noid] resembling a phlyctena.

• phlyctenular [flik-ten′u-l r] associated with the formation of phlyctenules, or of vesicle-like prominences.

• phlyctenule [flik′t n-ūl] a minute vesicle; an ulcerated nodule of the cornea or conjunctiva.

• phlyctenulosis [flik″t n-u-lo′sis] a nodular hypersensitive disease of the corneal and conjunctivial epithelium of the eye caused by an endogenous toxin.

• Phoca vitulina see harbor seal.

• Phocanema the former name of a genus of nematodes in the family Anisakidae, now belonging to Pseudoterranova.

  • P. decipiens found in the South American sea lion and fur seals. This species parasitizes pinnipeds (definitive hosts) and codfish (inter-mediate hosts) and may be transmitted to humans who eat the fish.

• phocine pertaining to or emanating from seals.

  • p. distemper see phocine distemper.

• Phocitrema fusiforme a liver fluke found in fur seal, ringed seal, and otter.

• phocomelia [fo″ko-me′le- ] congenital absence of the proximal portion of a limb or limbs, the distal parts being attached to the trunk by a small, irregularly shaped bone.

• phocomelus [fo-kom′ -l s] an animal exhibiting phocomelia.

• Pholcus phalangoides an arachnid of the family Pholcidae, commonly known as daddy-long-legs; crane fly or harvestman. Cosmopolitan.

• pholedrine an adrenergic vasopressor and cardiac stimulant.

• phomopsins [fo-mop′sins] cyclic hexapeptide hepatotoxic mycotoxins produced by the fungus Diaporthe toxica.

• Phomopsis leptostromiformis [fo-mop′sis] see Diaporthe toxica.

• phonal [fo′n l] pertaining to the voice.

• phonasthenia [fo″n s-the′ne-] weakness of the voice; difficult phonation from fatigue.

• phonation [fo-na′sh n] the utterance of vocal sounds.

• phonatory [fo′n -tor″e] subserving or pertaining to phonation.

• phonendoscope [fōn-en′do-skōp] a stethoscopic device that intensifies auscultatory sounds. Consists of a flat chamber closed at its contact with the skin by a thin plastic diaphragm. It is most useful in picking up higher-frequency sounds from the respiratory tract and heart. The classical bell stethoscope is more suited to picking up the lower-pitched heart sounds.

• phonic [fon′ik] pertaining to the voice.

• phon(o)- word element. [Gr.] relationship to sound, voice.

• phonoangiography [fo″no-an″je-og′r -fe] the recording and analysis of arterial bruits to estimate the extent of arterial stenosis.

• phonocardiogram [fo″no-kahr′de-o-gram] the record produced by phonocardiography.

• phonocardiograph [fo″no-kahr′de-o-graf] the instrument used in phonocardiography.

• phonocardiography [fo″no-kahr″de-og′r -fe] the graphic recording of heart sounds and murmurs; by extension, the term includes pulse tracings (carotid, apex, and venous pulse). Phonocardiography involves picking up, through a highly sensitive microphone, sonic vibrations from the heart, which are then converted into electrical energy and fed into a galvanometer, where they are recorded on paper. The procedure is most useful when there is evidence of heart murmurs or unusual heart sounds, such as gallops, that are difficult to discern by the human ear. Most recordings are made through an externally applied microphone but intracardiac recordings, made through a phonocatheter, are possible.

• phonocatheter [fo″no-kath′ -t r] a catheter with a device in its tip for picking up and transmitting sound.

• phonoendoscope [fo″no-en′do-skōp] a stethoscope with a large diameter flat head sealed by a thin plastic or celluloid diaphragm. Most useful for picking up small sounds from lung.

• phonogram [fo′no-gram] a graphic record of a sound.

• phonomyoclonus [fo″no-mi-ok′l -n s] myoclonus in which a sound is heard on auscultation of an affected muscle, indicating fibrillar contractions.

• phonomyogram [fo″no-mi′o-gram] a record produced by phono-myography.

• phonomyography [fo″no-mi-og′r -fe] the recording of sounds produced by muscle contraction.

• phonophoresis [fo″no-fo-re′sis] ultrasonic energy used to facilitate absorption of drugs across the epidermal barrier.

• phonophotography [fo″no-fo-tog′r -fe] photographic recording of the movements of a diaphragm set up by sound waves.

• phonoreceptor [fo″no-re-sep′t r] a receptor for sound stimuli.

• phonorenogram [fo″no-re′no-gram_] a record of the sounds produced by pulsation of the renal artery obtained by a phonocatheter passed through a ureter into the renal pelvis.

• phonostethograph [fo″no-steth′o-graf] an instrument by which chest sounds are amplified, filtered, and recorded.

• Phoradendron a genus of parasitic plants that grow on other trees; known in North America as mistletoes. Contain the toxic substance, phenethylamine. Dogs and cats have been poisoned eating berries, with hypersalivation, vomiting, diarrhea, and increased heart and respiratory rates. See also Viscum album (European mistletoe).

  • P. villosum Pacific mistletoe; contains cardiotoxic amines β-phenylethylamine and tyramine and causes sudden death due to heart failure.

• phorate an organophosphorus compound used as an insecticide and capable of causing poisoning.

• phorazetim a very toxic organophosphorus compound used as a rodenticide.

• -phore word element. [Gr.] a carrier.

• -phoresis word element. [Gr.] transmission.

• phoresy [for′ -se] a method of dispersal, e.g., of insect pests, in which the insect clings to a moving animal or other insect. Includes transmission of a parasite by a parasite, e.g., Histomonas meleagridis by Heterakis gallinarum and transmission of a parasite by free-living organisms, e.g., spread of Oesophagostomum dentatum eggs by flies.

• Phormia [for′me- ] a genus of blowflies. P. regina and P. terra-novae are involved in cutaneous myiasis in North America.

• phosdrin see mevinphos.

• phosmet an organophosphorus insecticide used as a spray or pour-on to control ectoparasites. Called also phthalophos.

• phosphatase [fos′f -tās] any of a group of enzymes capable of catalyzing the hydrolysis of esterified phosphoric acid, with liberation of inorganic phosphate, found in practically all tissues, body fluids, and cells, including erythrocytes and leukocytes.

  • p. inhibitor-1 inhibitor of phosphatase enzymes known to activate glycogen synthesis or inactivate glycogen breakdown. Need to themselves be phosphorylated by cAMP-dependent kinases before they are effective in their inhibitory activity.

• phosphate [fos′fāt] any salt or ester of phosphoric acid. 1. Phosphates are widely distributed in the body, the largest amounts being in the bones and teeth. They are continually excreted in the urine and feces, and must be replaced in the diet. Inorganic phosphates function as buffer salts to maintain the acid–base balance in blood, saliva, urine, and other body fluids. The principal phosphates in this buffer system are monosodium and disodium phosphate. Organic phosphates, in particular adenosine triphosphate (ATP), are used to store the chemical bond energy released during the oxidation of compounds such as glycogen or fatty acids, which may later be expended in muscle contraction. This is thought to occur through the hydrolysis of the so-called high-energy phosphate bond present in ATP, phosphocreatine, and certain other body compounds. See also hypophosphatemia, hyperphosphatemia. 2. used extensively in agricultural industry as fertilizers and organic compounds as cleaning agents.

  • p. binders usually aluminum- or calcium-based exchange compounds, used to bind dietary phosphates and limit their absorption from the intestine. Used in the treatment of the hyperphosphatemia of renal failure.
  • p. buffer important phosphate-containing buffers.
  • p. buffered saline (PBS) a special phosphate-buffered saline used in tissue cultures and for the storage and transport of bovine embryos.
  • p. calculi see struvite urolith.
  • dietary p. supplementation of the diet with phosphate in some form is a very common practice in farm animals. Materials used include rock phosphate (defluorination may be necessary), sodium dihydrogen phosphate produced by the agricultural chemical industry, calcium triphosphate, and bone meal or flour.
  • inorganic p. any salt of phosphoric acid.
  • p. retention a phenomenon resulting from reduced glomerular filtration; contributes to a chronic hypocalcemic state.
  • p. ridge see mineralization front.
  • p. rock see rock phosphate.

• phosphatemia [fos″f -te′me-] hyperphosphatemia.

• phosphatidic acid [fos″f -ti′dik] a precursor of triacylglycerols and some phospholipids. Consists of a glycerol backbone, with fatty acids bonded to carbons 1 and 2, and a phosphate group bonded to carbon-3. A key intermediate in the biosynthesis both of other phosphoglycerides and of triacylglycerols.

• phosphatidyl [fos″f -ti′d l] any of several univalent groups derived from phosphatidic acid; includes phosphatidylcholine, phosphatidyl ethanolamine, phosphatidyl inositol, and phosphatidylserine.

  • p. inositol 4,5-biphosphate (PIP₂) a minor phospholipid found in cell membranes; precursor of the second messengers inositol 1,4,5-triphosphate and diacylglycerol; acts as a docking phospholipid that recruits proteins to the plasma membrane and activates signal transduction pathways.

• phosphatidylcholine [fos″f -ti″d l-ko′lēn] phosphoglyceride with choline as the head group; major phospholipid component of cell membranes. Called also lecithin.

• phosphatidylethanolamine phosphoglyceride with ethanolamine as the head group; an important phospholipid component of cell membranes, found mainly in the inner leaflet of the membrane bilayer.

  • muramyl tripeptide p. a nonspecific immunostimulant; triggers activation of macrophages in the lungs and other tissues and generates production of tumor necrosis factor-α and other innate immune cytokines. Used as adjuvant immunotherapy to prevent metastases from osteosarcoma and hemangiosarcoma.

• phosphatidylinositol phosphoglyceride with inositol as the head group; minor component of the outer leaflet of themembrane bilayer. Phosphorylated forms (inositides) including phosphatidylinositol phosphate (PIP), phosphatidylinositol bisphosphate (PIP2), and phosphatidylinositol trisphosphate (PIP3) have important roles in cell signaling and membrane trafficking, the processes by which cargo such as proteins and other macromolecules are moved within and into and out of cells using membrane bound transport vesicles.

• phosphatidylserine [fos″f -ti″d l-ser′ēn] one of the phospholipids concerned in the structure of cell membranes. Usually found in the inner (cytosolic) half of the lipid bilayer.

• phosphaturia [fos″f -tu′re-] phosphates in the urine.

• phosphine [fos′fēn] a coal tar dye used as a stain; called Philadelphia yellow.

• phosphoamidase [fos″fo-am′ľ-dās] an enzyme that catalyzes the conversion of phosphocreatine to creatine and orthophosphate. Called also creatine phosphatase.

• phosphocreatine [fos″fo-kre′ -tin] a compound of creatine and phosphoric acid occurring in muscle, being an important storage form of chemical bond energy when excess ATP donates a phosphate group to creatine, and an energy source in muscle contraction via the transfer of the phosphate group to ADP to form ATP; both reactions catalyzed by creatine kinase. Called also creatine phosphate.

• phosphodiester group [fos″fo-di-es′t r] the bonds that join the 5′ phosphate of one nucleotide and the 3′-OH group of the adjacent nucleotide, i.e., the phosphate group esterified to both the 3′- and 5′-carbon atoms of the sugar.

• phosphodiesterase [fos″fo-di-es′t r] a group of enzymes that catalyze the hydrolysis of a phosphodiester.

• phosphoenolpyruvate (PEP) [fos″fo-e″nol-pi′roo-vāt] an intermediary metabolite in the Embden–Myerhof glycolytic pathway and in gluconeogenesis.

  P-42.

  

  Icteric mucous membranes in an English springer spaniel dog with a hemolytic crisis associated with PFK deficiency

• phosphoenolpyruvate–carboxykinase (PEP-CK) [fos″fo-e″nol-pi′roo-vāt kahr-bok″se-ki′nās] the rate-controlling enzyme in gluconeogenesis. It catalyzes the conversion of oxaloacetate to phosphoenolpyruvate (PEP) and carbon dioxide.

• 6-phosphofructokinase 1 an enzyme of the glycolytic (Embden–Meyerhof) pathway that catalyzes the conversion of fructose-6-phosphate to fructose-1,6-bisphosphate using ATP as the source of the phosphate. Allosteric enzyme regulating glycolysis.

  • p. (PFK) deficiency an inherited autosomal recessive disorder of glucose metabolism in English springer spaniels and American cocker spaniels. Affected dogs have exercise intolerance and develop a chronic hemolytic anemia. Caused by a point mutation in the M-type phosphofructokinase gene. A DNA test is available. Called also Type 7 glycogen storage disease, glycogenosis type VII, Tarui disease.

• 6-phosphofructokinase 2 enzyme catalyzing the phosphorylation of fructose-6-phosphate to fructose 2,6-bisphosphate using ATP as the source of the phosphate. Fructose 2,6-bisphosphate is a key allosteric influence of the activity of 6-phosphofructokinase 1.

• phosphoglucomutase [fos″fo-gloo″ko-mu′tās] a glycolytic pathway enzyme that catalyzes the conversion of glucose-1-phosphate to glucose-6- phosphate in a reversible reaction.

  • p.-2 a minor histocompatibility system in dogs; genetic polymorphism of this enzyme has been associated with graft-versus-host reactions.

• 6-phosphogluconate pathway see hexose monophosphate shunt, pentose phosphate pathway.

• phosphoglycerate kinase [fos″fo-glis′ r-āt] an enzyme that catalyzes the transfer of high-energy phosphate from 1,3-bisphosphoglycerate to ADP, forming ATP and 3-phosphoglycerate.

• phosphoglyceride [fos″fo-glis′ r-īd] a class of phospholipids, including lecithin and cephalin, consisting of two fatty acids esterified to a glycerol backbone. The third position of the glycerol molecule is esterified to a phosphate group that is bound to a head group e.g., choline, ethanolamine, serine or inositol. They are a major component of cell membranes.

• phosphoglyceromutase [fos″fo-glis″ r-o-mu′tās] an enzyme that converts 3-glycerophosphate to 2-glycerophosphate in one of the steps in the Embden–Meyerhof pathway. A dimeric protein existing as two isoforms, the M (muscle) and B (brain) forms.

• phosphokinase [fos″fo-ki′nās] see kinase.

• phospholipase [fos″fo-lip′ās] any of four enzymes (phospholipase A to D) which catalyze the hydrolysis of a phospholipid.

  • p. A₁, A₂ phospholipases catalyzing the hydrolysis of phospholipids at the sn-1 (A₁) or sn-2 (A₂) position to form free fatty acids and lysophosphatides.
  • p.B also known as lysophospholipase, an enzyme that catalyzes the cleavage of acyl chains from both the sn-1 and sn-2 positions of a phospholipid.
  • p.C a group of enzyme catalyzing the cleavage of the glycerophosphate bond of a phospholipid. Animal forms selectively hydrolyze membrane phosphatidylinositol 4,5-bisphosphate (PIP₂) to inositol 1,4,5-trisphosphate (IP₃) and 1,2-diacylglycerol. IP3 and DAG both have important second messenger functions.
  • p.D enzyme catalyzing the removal of the head group from phospholipids, e.g., phosphatidylcholine is hydrolyzed to choline and phosphatidic acid.

• phospholipid [fos″fo-lip′id] any lipid that contains phosphorus, including those with a glycerol backbone (phosphoglycerides and plasmalogens) or a backbone of sphingosine or a related substance (sphingomyelins). They are the major lipids in cell membranes.

  • p. bilayer a double layer of phospholipid molecules in which the hydrophobic fatty acid tails face the center and the hydrophilic head groups face the aqueous environment; forms the basic structural unit of all biological membranes.

• phospholipidosis [fos″f -lip″ľ-do′sis] a lysosomal storage disorder characterized by the excess accumulation of phospholipids in tissues.

• phosphoprotein [fos″f -pro′tēn] a conjugated protein in which phosphoric acid is esterified with a hydroxy amino acid.

• phosphorated [fos′f -rāt″ d] charged or combined with phosphorus.

• phosphorescence [fos″f -res′ ns] the emission of light without appreciable heat; it is characterized by the emission of absorbed light after a delay and at a considerably longer wavelength than that of the absorbed light. Caused by a number of bacteria, especially in seawater. One of them, Pseudomonas phosphorescens, may infect coldrooms via infected fish but does not constitute decomposition so that phosphorescent meat is still edible.

• phosphoribulokinase an enzyme that catalyzes the conversion of ATP and d-ribulose 5-phosphate to ADP and d-ribulose 1,5-diphosphate. Participates in carbon fixation.

• phosphoric acid [fos-for′ik] a crystalline acid H₃PO₄ formed by oxidation of phosphorus; its salts are called phosphates. Used in dentistry in the acid etch technique.

• phosphorolysis [fos″f -rol′ľ-sis] cleavage of a chemical bond resulting in the formation of a phosphate. Analogous to hydrolysis using inorganic phosphate functions in a manner similar to that of water.

• phosphorus (P) [fos-for′ s] a chemical element, atomic number 15, atomic weight 30.974. Phosphorus is an essential element in the diet. In the form of phosphates, it is a major component of the mineral phase of bone and is involved in almost all metabolic processes. It also plays an important role in cell metabolism. It is obtained by the body from milk products, cereals, meat, and fish, and its use by the body is controlled by vitamin D and calcium.

  • p.-32 (³²P) a radioisotope of phosphorus having a half-life of 14.3 days and emitting only beta rays; used in the form of sodium phosphate P-32 for treatment of polycythemia vera, chronic myelocytic leukemia, and chronic lymphocytic leukemia, and in localizing certain tumors during surgery.
  • calcium:p. ratio see calcium: phosphorus ratio.
  • inorganic p. any phosphorus-containing compound that does not also contain carbon.
  • p. nutritional deficiency causes rickets in the young and osteomalacia in adult ruminants. In less severe deficiency states, there is pica, growth retardation, infertility, and possibly retention of placenta. See also postparturient hemoglobinuria. An unlikely nutritional deficiency in carnivores.
  • p. poisoning is very rare because of the absence of elemental phosphorus from the environment. Causes severe gastroenteritis with vomiting and diarrhea. If the animal survives the gastroenteritis, there is a subsequent acute hepatic insufficiency.
  • p. restriction indicated in the dietary management of chronic renal disease and secondary hyperaparathyroidism; in dogs and cats, usually accomplished by reducing the content of meat.
  • p. supplements supplementing the diets of animals exposed to phosphorus deficient feeds is usually achieved by feeding bone meal, or calcium or sodium phosphates. All are readily assimilable but none are palatable, and special devices are often necessary to get animals to take required amounts. See also dietary phosphate.

• phosphorylase [fos-for′ -lās] a key regulatory enzyme that, in the presence of inorganic phosphate, catalyzes the removal of one glucose unit from glycogen to form glucose-1-phosphate. See also myophosphorylase.

  • citrulline p. see ornithine carbamoyl transferase.
  • p. kinase an enzyme that activates phosphorylase by catalyzing the phosphorylation of serine. See also kinase.

• phosphorylated glycerolipids [fos-for′ -lāt-ed] chief constituents of the lipid bilayer of cell membranes in which apolar acyl chains face each other in the membrane interior. Called also glycerophospholipid.

• phosphorylation [fos-for″ -la′sh n] the process of introducing a phosphate group into an organic molecule.

  • oxidative p. the final common oxidative pathway in which high-energy phosphate bonds are formed by phosphorylation of ADP to ATP; ATP synthase harnesses the proton motive force generated from pumping of protons from the matrix of mitochondria across the inner mitochondrial membrane to the intermembrane space that is coupled with the transfer of electrons along a chain of carrier proteins, with molecular oxygen as the final acceptor.
  • substrate-level p. formulation of high-energy phosphate bonds in a reaction in which the phosphorylation of ADP or GDP to ATP or GTP is directly coupled to the splitting of a high-energy metabolite, e.g., in glycolysis and the tricarboxylic acid cycle.

• phosphosphingolipids a subset of sphingolipids that is characterized by a phosphorylated hydroxyl group at C1 of a sphingoid base and can be additionally modified at the sphingoid base, as well as at the phosphate group. Species with unmodified phosphate group are involved in various cell signaling pathways, those carrying phosphate group modifications are part of biological membranes. Ceramide phosphocholine (sphingomyelin) is the most abundant member of the group found in mammalian tissues.

• phosphotransacetylase an enzyme that catalyzes the transfer of an acetyl group between acetylphosphate and acetylcoenzyme A.

• phosphotransferase [fos″fo-trans′f r-ās] any of a class of enzymes that catalyze the transfer of a phosphate group.

• photic [fo′tik] pertaining to light.

• Photinia genus of garden plants in the family Rosaceae; some species can cause cyanide poisoning; called also Christmas berry, Chinese photinia.

• phot(o)- word element. [Gr.] relationship to light.

• photo timer A timer connected with the output optical detector used to control x-ray exposure time automatically for spot filming or photofluorography.

• photoactivated see photoaggravated.

• photoactive [fo″to-ak′tiv] reacting chemically to sunlight or ultraviolet radiation.

• photoaggravated [fo″to-ag′r -vāt″ d] condition produced when a preexisting condition worsens on being exposed to sunlight. Called also photoactivated.

  • p. dermatoses term used in human medicine when referring to pemphigus, lupus erythematosus, bullus pemphigoid; may be applicable to the same diseases in dogs.
  • p. vasculitis a dermatosis of horses affecting only the white extremities of the limbs.

• photoallergy [fo″to-al′ r-je] a hypersensitivity that develops against the photoproduct of an exogenous chemical.

• Photobacterium damselae subsp. piscicida causes pseudotuberculosis in a range of marine warm water species especially in the Mediterranean and Japan. Previously known as Pasteurella piscicida.

• photobiology [fo″to-bi-ol′ -je] the branch of biology dealing with the effect of light on organisms.

• photobiotic [fo″to-bi-ot′ik] living only in the light.

• photocatalyzis [fo″to-k -tal′ľ-sis] promotion or stimulation of a chemical reaction by light.

• photocatalyzt [fo″to-kat′ -list] a substance, e.g., chlorophyll, that brings about a chemical reaction on exposure to light.

• photochemical [fo″to-kem′ -k l] in laser treatment, the laser light is absorbed and converted into chemical energy.

• photochemistry [fo″to-kem′is-tre] the branch of chemistry that deals with the chemical properties or effects of light rays or other radiation.

• photochemotherapy [fo″to-ke″mo-ther′ -pe] treatment by means of drugs (e.g., methoxsalen) that react to ultraviolet radiation or sunlight.

• photochromogen [fo″to-kro′m -j n] a microorganism in which pigmentation develops as a result of exposure to light. A characteristic of Runyon Group I mycobacteria.

• photocoagulation [fo″to-ko-ag″u-la′sh n] condensation of protein by the controlled use of a laser; used especially in the treatment of retinal detachment (retinopexy), destruction of abnormal retinal vessels (in primates), intraocular tumor masses, or ciliary body epithelium (in glaucoma).

• photodermatitis, photodermatosis [fo″to-dur″m -ti′tis] an abnormal state of the skin in which light is an important causative factor, e.g., actinic dermatitis.

• photodisruptive [fo″to-dis-rup′tiv] in laser treatment, the laser energy is converted to shock waves that disrupt tissues or structures; used in lithotripsy and ophthalmic surgery.

• photodynamic [fo″to-di-nam′ik] activated or made more powerful by light.

  • p. agent a substance that, when activated by light, causes damage to tissue. It may be exogenous and absorbed preformed from the environment, or endogenous in that it is formed within the body as an abnormal metabolite (e.g., porphyrins) or as a normal metabolite (e.g., phylloerythrin) and accumulates in tissues because of faulty excretion, e.g., in hepatic disease.
  • p. therapy the therapeutic use of a photodynamic agent, administered locally or which accumulated in tissues, activated by light to treat certain diseases, in particular skin cancers and other skin conditions.

• photoelectric pertaining to the electrical effects of light or other radiation.

  • p. effect the incoming x-ray photon ejects an electron from an inner shell of a tissue atom and is absorbed by the patient. The major contributor to image contrast in diagnostic radiology. Also called photoelectric absorption

• photofluorography [fo″to-floor-og′r -fe] the photographic recording of fluoroscopic images. Called also fluorography and fluororadiography.

• photogenic [fo″to-jen′ik] 1. produced by light. 2. emitting or producing light.

• photogrammetry [fo″to-gram- -tre] a stereophotographic technique for estimating body weight and parts of the body by three-dimensional measurement.

• photohemolysis [fo″to-he-mol′ -sis] lysis of red cells when the patient is exposed to sunlight. Occurs in erythropoietic protoporphyria.

• photokinetic [fo″to-kľ-net′ik] moving in response to the stimulus of light.

• photolysis [fo-tol′ľ-sis] chemical decomposition by light.

• photolyte [fo′to-līt] a substance decomposed by light.

• photometer [fo-tom′ -t r] a device for measuring the intensity of light.

• photometry [fo-tom′ -tre] an analytic chemistry technique to measure the concentration of substances and the activities of enzymes by measuring the intensity of light passing through it.

• photomicrograph [fo″to-mi′kro-graf] a photograph of an object as seen through an ordinary light microscope.

• photomirex historically used as a pesticide and fire retardant and long banned but now an environmental pollutant capable of causing testicular degeneration in animals ingesting it.

• photomyoclonic [fo″to-mi″o-klon′ik] photomyogenic.

• photomyogenic [fo″to-mi″o-jen′ik] clonic spasm of muscles when the patient is exposed to flashes of light. Requires electroencephalographic recognition of response to be a valid result.

• photon [fo′ton] a particle (quantum) of radiant energy.

  • x-ray p. a particle of x-ray energy.

• photoperiod [fo′to-pēr″e- d] the period of time per day that an organism is exposed to daylight (or to artificial light).

• photoperiodicity [fo″to-pēr″e-o-dis′ľ-te] the rhythm of certain bio-logical phenomena such as hibernation and reproductive activity that are determined by the regularly recurring changes in light and dark caused by the annual passage of the earth about the sun.

• photoperiodism [fo″to-pēr′e- d-iz- m] the physiological and behavioral reactions brought about in organisms by changes in the duration of daylight and darkness, e.g., in reproductive activity, shedding of hair. Birds respond to longer daylight hours by increased sexual activity. Use is made of the phenomenon by using artificial light to stimulate egg production.

• photophilic [fo″to-fil′ik] thriving in light.

• photophobia [fo″to-fo′be- ] abnormal visual intolerance to light. Expressed in animals by excessive closing of the eyelids when exposed to light.

• photophthalmia [fo″tof-thal′me- ] ophthalmia caused by exposure to intense light.

• photopia [fo-to′pe- ] day vision.

• photoreactivation [fo″to-re-ak″tľ-va′sh n] reversal of the biological effects of ultraviolet radiation on cells by subsequent exposure to visible light.

• photoreception [fo″to-re-sep′sh n] perception of light waves that are in the range of visible light.

• photoreceptive [fo″to-re-sep′tiv] sensitive to stimulation by light.

• photoreceptor [fo″to-re-sep′t r] a nerve end organ or receptor sensitive to light. In the retina of the eye, the rods, and cones.

• photorefractoriness [fo″to-re-frak′t r-e-nes] the state of being refractory to the stimulus of light; an important feature of sexual non-receptivity in some species.

• photoretinitis [fo″to-ret″ľ-ni′tis] retinitis due to exposure to intense light.

• photosensitive [fo″to-sen′sľ-tiv] exhibiting abnormally heightened sensitivity to sunlight. See also photosensitive dermatitis.

• photosensitivity [fo″to-sen″sľ-tiv′ľ-te] the state of being photosensitive.

• photosensitization [fo″to-sen″sľ-tľ-za′sh n] the development of abnormally heightened reactivity of the skin to sunlight. In food animals the principal photodynamic agents are porphyrins and phylloerythrin. The principal clinical manifestations are dermatitis, especially of nonpigmented skin, and areas exposed to the sun, such as the lateral aspects of the teats and the ventral aspect of the tongue, exposed when licking the nose, and conjunctivitis. There may be an accompanying hepatic insufficiency or porphyrinuria. See liver dysfunction, photosensitive dermatitis. Called also light sensitization. There is a long list of drugs that can cause photosensitization reactions. Antineoplastics, antimicrobials, diuretics, hypoglycemic agents, and even antihistamines are capable of triggering photosensitivity reactions in certain individuals.

  • corticosteroid-induced p. photosensitive dermatitis of the teats in cows injected with corticosteroids to terminate pregnancy.
  • inherited p. in Corriedale and Southdown sheep is caused by an inherited liver transport defect. The liver is histologically normal but phylloerythrin excretion is impeded. Photosensitive dermatitis appears as soon as the lambs begin to eat grass.
  • primary p. caused by the ingestion of exogenous photosensitizing agents such as dianthrone derivatives (e.g., hypericin, fagopyrin), phomopsins from fungus-infected lupins (lupinosis), muranocoumarins, perloline, phenothiazine, rose bengal.

    P-43a.

    

    Hereford with severe dermatitis from photosensitivity

    P-43b.

    

    Photosensitive dermatitis on the teat of a cow

  • secondary p. secondary to hepatic cell damage, biliary obstruction leading to the accumulation in the body of phylloerythrin, a metabolic end-product of chlorophyll.

• photosensitizing causing photosensitivity.

  • p. plants. some plants contain primary photodynamic agents, e.g., dianthrone derivatives and furanocoumarins. Others are hepatotoxic or carry hepatotoxic mycotoxin-producing fungi and are indirectly photosensitizing by interfering with the excretion of phylloerythrin through the animal’s biliary system.

• photostable unchanged by the influence of light.

• photostimulator [fo″to-stim′u-la″t r] a source of an intense flash of light of very short duration that serves as the light stimulus for electroretinography.

• photosynthesis [fo″to-sin′th -sis] a chemical combination caused by the action of light; specifically the formation of carbohydrates from carbon dioxide and water in the chlorophyll tissue of plants under the influence of light.

• phototaxis [fo″to-tak′sis] the movement of cells and microorganisms toward light.

• phototherapy [fo″to-ther′ -pe] treatment of disease by exposure to light. Malignant tumors are treated by using photosensitizing drugs and laser light.

• photothermal [fo″to-thur′m l] in laser treatment, the laser light is absorbed and converted to heat in the tissues.

• phototoxic [fo′to-tok″sik] having a toxic effect triggered by exposure to light.

• phototoxicity [fo″to-tok-sis′ľ-te] pertaining to phototoxic.

• primary p. see solar dermatitis, sunburn.

• phototrophic [fo″to-tro′fik] capable of deriving energy from light.

• phototropism [fo-tot′r -piz- m] 1. the tendency of an organism to turn or move toward (positive phototropism) or away from (negative phototropism) light. 2. change of color produced in a substance by the action of light.

• photuria [fo-tu′re- ] excretion of urine having a luminous appearance.

• PHPV persistent hyperplastic primary vitreous.

• phrenetic [fren-et′ik] maniacal.

• phrenic [fren′ik] pertaining to the diaphragm.

  • p. nerve one of the paired nerves to the diaphragm that arises from the caudal cervical nerves (4–7, the specific branches varying with species), passes through the thoracic inlet and in the mediastinum and adjacent structures to the diaphragm.

• phrenicectomy [fren″ľ-sek′t -me] resection of the phrenic nerve.

• phrenicoexeresis [fren″ľ-ko-ek-ser′ -sis] extraction of a portion of the phrenic nerve, producing one-sided paralysis of the diaphragm and partial collapse of the corresponding lung.

• phrenicotomy [fren″ľ-kot′ -me] surgical division of the phrenic nerve.

• phrenicotripsy [fren″ľ-ko-trip′se] phrenemphraxis.

• phrenitis [fr -ni′tis] 1. delirium or frenzy. 2. diaphragmitis.

• phren(o)- word element. [Gr.] referring to diaphragm, phrenic nerve or mind.

• phrenocolic [fren″o-kol′ik] pertaining to the diaphragm and colon.

• phrenogastric [fren″o-gas′trik] pertaining to the diaphragm and stomach.

  P-44.

  

  Fungating phycomycosis lesions on the chest of a horse

• phrenohepatic [fren″o-h -pat′ik] pertaining to the diaphragm and liver.

• phrenoplegia [fren″o-ple′j ] paralysis of the diaphragm.

• phrenosin [fren′o-sin] a cerebroside containing cerebronic acid attached to the sphingosine.

• phthalamic acid [thal′ m-ik] an organic herbicide with low toxicity for animals.

  • alpha-pthalic-acid esters, o-phthalic acid plasticizers in polyvinyl products and also used in paints, varnishes, personal cares, cosmetics, paper coatings, and adhesives; act as endocrine disrupting agents and are linked to neural, reproductive, and developmental toxicity.

• phthalofyne an anthelmintic, a derivative of benzenedicarboxylic acid, used specifically for the treatment of whipworm (Trichuris vulpis) in dogs.

• phthalophos see phosmet.

• phthalylsulfacetamide a sulfonamide antibacterial agent with high solubility; used for topical application to the skin and the conjunctiva.

• phthalylsulfathiazole the phthyl form of sulfathiazole; it is poorly absorbed from the gastrointestinal tract. When administered orally it is hydrolyzed to sulfathiazole, which is the effective antibacterial agent.

• phthisis [thi′sis; ti′sis] 1. a wasting of the body. See also myelophthisis. 2. tuberculosis.

  • p. bulbi shrinkage and disorganization of the eye due to scar formation following severe or chronic uveitis or more commonly chronic glaucoma.

• phyco- word element. [Gr.] relationship to seaweed, algae.

• phycology the scientific study of algae.

• phycomycetes [fi″ko-mi-se′tēz] previously used to describe fungi that produce nonseptate hyphae. The fungi that were once classified within this group are now within the Zygomycetes, Chytridiomycetes, Plasmodiophoromycetes, Hyphochytridiomycetes, Trichomycetes, and Oomycetes.

• phycomycosis [fi″ko-mi-ko′sis] any of a group of acute fungal diseases caused by members of the Phycomycetes. See pythiosis, lagenidiosis, and zygomycosis.

  • equine p. infectious fungal disease of the skin or mucosae (nasal or conjunctiva) of horses associated with infection by Pythium insidiosum (syn Hyphomyces destruens), Basidiobolus haptosporus, Conidiobolus coronatus (syn. Entomophthora coronatus), Rhinosporidium spp., Pseudallescheria boydii, Alternatira alternata, Scedosporium proliferans, and others. Occurs predominantly but not exclusively in tropics and subtropics. Grossly similar lesions caused by infection by the parasite Habronema megastoma, amyloidosis, or aspergillosis.

• Phyllanthus [f -lan′th s] a genus in the plant family of Euphorbiaceae.

  • P. abnormis North American plant; contains an unidentified toxin that causes liver and kidney damage manifested by compulsive walking, tenesmus, rectal prolapse, petechiation, and death. Called also spurge.
  • P. gasstroemii may cause cyanide poisoning.
  • P. lacunarius causes gastroenteritis.

• phylloerythrin [fil″o-er′ľ-thrin] an end-product of chlorophyll metabolism normally excreted in the bile. It is a photodynamic agent and its accumulation in the tissues in animals on a diet of green feed and with liver insufficiency leads to the development of photosensitization.

• phylloquinone [fil″o-kwin′ōn] see phytomenadione.

• phylogeny [fi-loj′ -ne] the evolutionary history of a race or group of organisms.

• phylum [fi′l m] pl. phyla [L., Gr.] a primary division of the plant or animal kingdom, including organisms that are assumed to have a common ancestry.

• phyma [fi′m ] pl. phymata [Gr.] a skin tumor or tubercle.

• Physalia physalis [fi-sa′le- ] see Portuguese man-of-war.

• Physalis [fis′ -lis] genus of plants in the family Solanaceae; suspected of poisoning livestock. Includes P. minima, P. peruviana. Called also wild or ground cherry.

• Physaloptera [fis″ -lop′tr-] a genus of spirurid worms in the family Physalopteridae found in the stomachs of their hosts. The gastric mucosa may become eroded, inflamed, and produce much mucus. Clinically there may be vomiting, melena, anorexia, and weight loss.

  • P. alata found in the gizzard and intestines of doves and other birds.
  • P. canis found in the stomach of cats and dogs.
  • P. caucasica found in the esophagus, stomach, and intestines of simian primates.
  • P. clausa, P. dispar, P. erinacea found in hedgehogs.
  • P. dilitata found in the stomach of simian primates.
  • P. felidis found in the stomach and intestines of cats.
  • P. gemina found in fowl and cat.
  • P. maxillaris found in skunks and Procyon and Mustela spp.
  • P. poicilometra found in simian primates.
  • P. praeputialis found in the stomach of cats and wild cats.
  • P. pseudopraeputialis found in the stomach and larynx of cats and coyotes.
  • P. rara found in the stomach and duodenum of dogs and wild dogs and cats.
  • P. tumefasciens found in the stomach of simian primates.

• Physconelloides zenaidurae a biting louse of the family Philopteridae, found on pigeons.

• physeal [fiz′e- l] pertaining to growth or to that part of a bone that is responsible for lengthening—the physis.

  • p. delayed closure occurs when there is inadequate growth hormone, as in hypopituitarism.
  • p. dysplasia essentially a disease of horses that consists of a self-limiting disturbance of endochondral ossification affecting the metaphyseal physes of young horses; called also physitis, epiphysitis.
  • p. focal closure occurs as a result of damage to or displacement of the growth plate; bony bridges develop uniting the epiphysis and the metaphysis, many leading to bone deformities.
  • p. premature closure usually the result of injury and seen most often in dogs. Causes abnormal development of the bone, the type and severity of which depends on the age of the animal and the particular location. The most vulnerable are the radius and ulna, mainly because closure of one physis results in unequal growth of the two parallel bones, often resulting in an angular deformity.
  • p. scar on imaging, the faintly radiopaque line seen in bones of mature animals representing the closed physis

• physic [fiz′ľk] 1. the art of medicine and therapeutics. 2. a medicine, especially a cathartic. See also purging ball.

  • p. nut Jatrophacurcas, J. multifida.

• physic ball see purging ball.

• physical [fiz′ľ-k l] pertaining to the body, to material things, or to physics.

  • p. findings results of a physical examination. Observations made visually, by auscultation, palpation, smell, percussion, succussion, and ballottement.
  • p. map in genetics, determination of the array of genes within a DNA segment of a chromosome.
  • p. therapist one who is skilled in the physical and therapeutic techniques of helping to alleviate suffering from muscle, nerve, joint and bone diseases and from injuries and to overcome or prevent disabilities. Among the procedures used by the physical therapist are exercise to increase strength, endurance, coordination, and range of motion; electrical stimulation to activate paralyzed muscles; massage, vibrators and many other patented devices to try to improve the circulation and condition of a part. Called also physiotherapist.

• physician [fľ-zish′ n] in human medicine, a licensed medical graduate who practices medicine as distinct from surgery; a term not used in veterinary medicine.

• physicochemical [fiz″ľ-ko-kem′ľ-k l] pertaining to both physics and chemistry.

• physics [fiz′ik] the study of the laws and phenomena of nature, especially of forces and general properties of matter and energy.

• physi(o)- word element. [Gr.] pertaining to nature.

• physiochemical [fiz″e-o-kem′ľ-k l] pertaining to both physiology and chemistry.

• physiologic, physiological [fiz″e-o-loj′ik] 1. pertaining to physiology; 2. normal; not pathological. Conforming to the normal function of an organ or the body as a whole.

  • p. saline 0.9% solution of sodium chloride. See also normal saline.

• physiologist [fiz″e-ol′ -jist] a specialist in physiology.

• physiology [fiz″e-ol′ -je] 1. the science that deals with the functions of the living organism and its parts, and of the physical and chemical factors and processes involved. 2. the basic processes underlying the functioning of a species or class of organism, or any of its parts or processes.

  • cell p. the scientific study of phenomena involved in cell growth and maintenance, self-regulation and division of cells, interactions between nucleus and cytoplasm, and general behavior of protoplasm.
  • morbid p., pathological p. the study of disordered functions or of function in diseased tissues.

• physiopathological pertaining to the physiology, or derangement of normal physiology, underlying disease states.

• physiotherapist [fiz″e-o-ther′ -pist] physical therapist.

• physiotherapy [fiz″e-o-ther′ -pe] use of physical therapy employing mechanical force and movements, manual therapy, exercise therapy, and electrotherapy, to promote and restore mobility and function.

• physique [fľ-zēk′] the body organization, development, and structure. In animals it is more customary to speak of conformation.

• physis [fi′sis] the segment of a bone that is responsible for lengthening. There are four zones within the physis, the resting cartilage zone, the proliferating cartilage zone, the zone of hypertrophy, and the zone of calcification. Called also the growth plate. See also physeal.

• -physis [fi′sis] word element. [Gr.] to grow, growth. See physis.

• physitis [fis-ī′tis] see physeal dysplasia.

• phys(o)- word element. [Gr.] relationship to air, gas.

• Physocephalus [fi″so-sef′ -l s] a spirurid nematode in the family Spirocercidae. Causes gastritis manifested by anorexia, increased thirst, loss of weight, and rarely death. Includes P. cristatus (dromedary) and P. sexalatus (pig).

• physohematometra [fi″so-hem″ -to-me′tr] gas and blood in the uterine cavity.

• physohydrometra [fi″so-hi″dro-me′tr ] gas and serum in the uterine cavity.

• physometra [fi″so-me′tr ] gas in the uterine cavity.

• Physopsis [fi-sop′sis] water snail, a subgenus of Bulinus; an intermediate host for several blood flukes, Schistosoma spp., in sub-Saharan Africa including S. haematobium.

• physopyosalpinx [fi″so-pi″o-sal′pinks] gas and pus in the oviduct.

• physostigmine [fi″zo-stig′mēn] an alkaloid usually obtained from the dried ripe seed of Physostigma venenosum; it is used in the treatment of myasthenia gravis and in treating overdosage of atropine, scopolamine and other anticholinergics; used also as a topical miotic in the form of the base and of the salicylate and sulfate salts.

  • p. challenge test a test for the diagnosis of cataplexy; after increasing doses of physostigmine, affected dogs show a dose-related severity of reactions when offered food.

• phytase [fi′tās] a hydrolase enzyme found in plants; catalyzes the hydrolysis of phytic acid to inositol and phosphoric acid.

• phytate [fi′tāt] inositolhexaphosphoric acid; a source of phosphorus for ruminants and horses but indigestible to carnivores. Present in large amounts in plants.

• phytate-phosphorus relatively unavailable phosphorus combined with phytic acid, in feeds with a high fiber content. See also phytate.

• phytic acid [fi′tik] used synonymously with phytate. See also phytin.

• phytin the calcium and magnesium salt of phytic acid.

• phyt(o)- word element. [Gr.] relating to plant or vegetation.

• phytoagglutinin an agglutinin of plant origin.

• phytoalexins [fi″to- -lek′sins] defense chemicals produced by plants in response to tissue damage by microbes (fungi, bacteria) or herbivores, usually insects. Such chemicals may be toxic to vertebrate animals that eat the affected plants, e.g., furanocoumarins in fungus-infected parsnips may cause primary photosensitization in pigs.

• phytobezoar [fi″to-be′zor] a bezoar composed of vegetable fibers. Common in cattle as abomasal inclusions. Important as a cause of pyloric or intestinal obstruction. See intestinal obstruction, Romulea, bovine colic.

• phytoestrogens [fi″to-es′tro-j ns] substances with activity as estrogens produced in plants. Includes isoflavones and coumestans. Most of these agents undergo major changes in the rumen, the agents becoming much more potent as a result of the change, e.g., formononetin, which has very little activity is converted to a potent estrogen.

• phytogenous [fi-toj′ -n s] derived from plants, or caused by a vegetable growth.

• phytohemagglutinin [fi″to-hēm″ -gloo′tľ-nin] a lectin found in beans that agglutinates both red and white blood cells and exhibits mitogenic activity.

• phytoid [fi′toid] resembling a plant.

• Phytolacca [fi″to-lak′ ] genus of plants in the family Phytolaccaceae; suspected to contain a toxic saponin that causes enteritis with vomiting, abdominal pain, and diarrhea. The illness may be fatal. Includes P. americana (P. dodecandra poke or pokeweed), P. dioica, P. octandra (ink weed),

• phytomedicine [fi″to-med′ľ-sin] see herbal medicine.

• phytomenadione [fi″to-men″ -di′ōn] vitamin K1; the major form of vitamin K found in plants; used as an antidote in poisoning by warfarin and other anticoagulant rodenticides. Called also phylloquinone and phytonadione.

• phytonadione [fi-to″n -di′ōn] vitamin K.

• phytoparasite [fi″to-par′ -sīt] any plant parasitic organism.

• phytophagous [fi-tof′ -g s] plant-eating.

• phytophotocontact dermatitis [fi″to-fo″to-kon′takt dur″m -ti′tis] photosensitization following skin contact with plants that leads to absorption of psoralens.

• phytophotodermatitis [fi″to-fo″to-dur″m -ti′tis] phototoxic dermatitis due to contact with certain plants and subsequent exposure to sunlight.

• phytoplankton [fi″to-plank′ton] see plankton.

• phytoprecipitin [fi″to-pre-sip′ľ-tin] a precipitin formed in response to vegetable antigen.

• phytosis [fi-to′sis] any disease caused by a phytoparasite.

• phytosterol [fi-tos′t r-ol″] a sterol of vegetable origin.

• phytotherapy [fi″to-ther′ -pe] see herbal medicine.

• phytotoxic [fi′to-tok″sik] 1. pertaining to phytotoxin. 2. poisonous to plants.

• phytotoxin [fi′to-tok″sin] an exotoxin produced by certain species of higher plants; any toxin of plant origin.

• phytotrichobezoars [fi″to-tri″ko-be′zors] fiber balls found in the intestines. They are light compared with enteroliths, being composed of plant or animal fiber cemented by some phosphate salt. They are smooth and usually have a hairy surface. They are usually innocuous.

• P_i inorganic orthophosphate.

• pI isoelectric point.

• pi the 16th letter of the Greek alphabet, Π or π.

• PI-3 virus parainfluenzavirus 3.

• Pi lines thin, black lines running longitudinally across the x-ray film caused by chemical deposits on the rollers in the automatic developer tank.

• pia mater [pi′ , pe′] [L.] the innermost of the three meninges covering the brain and spinal cord.

• pia-arachnitis [pi″ -ar″ak-ni′tis] leptomeningitis; inflammation of the leptomeninges, or pia mater, and arachnoid.

• pia-arachnoid [pi″ - -rak′noid] the pia mater and arachnoid considered together as one functional unit; the leptomeninges.

• piaffe [Fr.] a strut; a horse dressage gait in which the horse moves actively but stays in place. The action is high.

• pial [pi′ l, pe′ l] pertaining to the pia mater.

• piarachnitis [pi″ar″ak-ni′tis] leptomeningitis; pia-arachnitis.

• piarachnoid [pi″ -rak′noid] pia-arachnoid.

• pica [pi′k ] craving for, and ingestion of, nonfood items. Pica may be a clinical sign associated with various medical causes, such as maldigestion/malabsorptive conditions (exocrine pancreatic insufficiency, inflammatory bowel disease), intestinal parasitism, malnutrition, and disorders that lead to polyphagia. Alternatively, pica may be primarily behavioral in nature and linked to conditions such as separation anxiety. Often caused by a nutritional deficiency of bulk, fiber or a specific nutrient, e.g., phosphorus, salt, or copper. May lead to botulism, foreign body lodgment in mouth, pharynx, esophagus, in the reticulum to cause reticuloperitonitis, at the pylorus and, in the horse, in the small colon. Called also allotriophagia.

• Picardy shepherd see Berger picard.

• Pichia ohmeri [pich′e- ] a yeast that has caused bovine mastitis.

• pick [pik] a sharp-pointed instrument, of varying size and function, e.g., tooth pick, hoof pick.

  • hoof p. consists of a palm grip and a stem with a sharp point. Used for picking out debris, especially stones, from between the bars and the frog of horses’ hooves.

• picking out removing the accumulated dirt, manure, and stones from the sole of the horse’s feet with a hoof pick.

• pickling [pik′ling] a form of curing in which the meat is immersed in a solution of the curing agents instead of being rubbed with and packed in the dry agent (bacon curing). The method is faster but does not provide the mouth-watering, smoky dryness of a York or Virginian ham.

• Pick’s cell see Pick’s cell, sphingomyelinosis.

• pickwickian syndrome [pik-wik′e- n] alveolar hypoventilation, somnolence and disordered breathing during sleep associated with extreme obesity as seen in Charles Dickens’ fat boy in the Pickwick Papers. A similar syndrome is observed rarely in dogs. Called also obesity hypoventilation syndrome.

• picloram a picolinic acid derivative used as a herbicide; of low toxicity to animals but run off can cause problems to fish.

• pico- (p) [It.] small; prefix used in the metric system of measurements to designate 10⁻¹² (one-million-millionth) part of the unit, picogram.

• picobirnaviruses a name provisionally applied to small (35 nm) double segment, double-stranded RNA viruses. commonly found in feces of numerous species; a putative cause of diarrhea and respiratory disease.

• picogram (pg) [pi′ko-gram] one million-millionth (10⁻¹²) gram.

• picolinic acid a base compound from which a number of derivatives are produced and used as herbicides.

• picometer, picometre (pm) [pi′ko-me′t r] a unit of length, 10−12 meter.

• Picornaviridae [pľ-kor″n -vir′ľ-de] a family of small (25 nm diameter), nonenveloped single-stranded, plus sense RNA viruses, the members of which cause a variety of diseases including poliomyelitis of humans (Enterovirus), respiratory disease in cattle (Rhinovirus), encephalomyocarditis in pigs (Cardiovirus), foot-and-mouth disease and equine rhinitis A (Aphthovirus), porcine encephalomyelitis (Teschovirus), avian encephalomyelitis and hepatitis A of humans (Hepatovirus), and equine rhinitis B viruses (Erbovirus), bovine and porcine kobuviruses (Kobuvirus).

• picornavirus [pi-kor′n -vi″r s] a member of the virus family Picornaviridae.

• picrate [pik′rāt] any salt of picric acid.

  • p. test a field test for cyanogenetic compounds in plants and gut contents. Based on the conversion of yellow sodium picrate to a brick red color in contact with hydrocyanic acid. Called also Henrici test.
  • alkaline p. test a method of creatinine assay based on the orange-red color produced by creatinine reacting with alkaline picrate (Jaffe reaction).

• picric acid [pik′rik] a substance used as a dye, tissue fixative, antiseptic, astringent, and stimulant of epithelialization. Caution: it can be ignited on percussion or by heating to above 570°F (300°C). Also called trinitrophenol.

• picrocarmine [pik″ro-kahr′min] a histological stain consisting of a mixture of carmine, ammonia, distilled water, and aqueous solution of picric acid.

• picrotoxin [pik′ro-tok″sin] a central nervous system and respiratory stimulant formerly used in barbiturate and other anesthetic poisonings; extracted from the seeds of the plant Anamirta cocculus.

• Pictou disease Canadian term for pyrrolizidine alkaloidosis in cattle eating Senecio jacobaea.

• picture frame theory a theory of wound healing and contraction stating that mitotically active cells migrate inward from the margin of the wound, pulling on the material within the margins of the defect. See also pull theory.

• PIE syndrome pulmonary infiltrates with eosinophils; see eosinophilic bronchopneumopathy.

• piebald [pi′bawld] a horse coat color of large, distinct patches of black and white. The patches are irregular in shape.

• piebaldism [pi′bawld-iz- m] a condition in which the skin is partly brown and partly white, as in partial albinism and vitiligo. See also Waardenburg’s syndrome.

• piecemeal patchy, e.g., necrosis of the liver in which individual hepatocytes are attacked by small groups of inflammatory cells and fine, fibrous septa follow extension of the inflammatory process beyond the limiting plate.

• pieces a wool-classer’s term; when classing fleece wool preparatory to sale, these are the inferior pieces of wool, including skirtings from around the edge and broken wool.

• pied [pīd] coloring of haircoat or feathers that consists of uneven patches or spots of color on a white or cream background.

• Piedmont, Piedmontese a breed of dual-purpose cattle, white or pale gray, with black points. They have short horns and a deep forehead, like other brachyceros-type cattle.

• piedra [pya′dr ] asymptomatic superficial fungal disease of the extrafollicular hair shaft caused by Piedraia hortae (black piedra) or Trichosporon beigelii (white piedra)

• Pieris¹ temperate zone garden plant genus in the family Ericaceae. Contains grayanotoxin (andromedotoxin). Includes P. formosanum, P. japonicum (Andromeda japonica, Japanese pieris), P. ovalifolia.

• Pieris² an insect genus in the order Lepidoptera.

  • P. brassicae the cabbage butterfly of which the caterpillars are cryptoxic, causing colic, stomatitis, and paraplegia.

• -piesis word element. [Gr.] pressure.

• Pietrain semi—lop-eared pig with white color body and black or red spots around which are rings of lighter pigmentation.

  • P. creeper pigs inherited myopathy with atrophy of type-1 myofibers in the Pietrain breed of pigs; characterized by progressive muscular weakness in young pigs, progressing to recumbency. An autosomal recessive trait. Called also creeper pigs.

• piezoelectric [pi-e″zo-e-lek′trik or pē″zo-e-lek′trik] the generation of electricity in response to mechanical stimulation. See ultrasonography.

  P-45.

  

  Pietrain pig

• PIF prolactin inhibitory factor.

• pig [pig] an even-toed nonruminant ungulate with a simple stomach. A member of the suborder Suiformes of the order Artiodactyla. Includes domestic pigs, which are very prolific, heavy, ponderous, rapid-growing, grunting creatures bred predominantly for meat, leather, and hair (for brushes) but increasingly kept as pets, especially domesticated miniature breeds. Also used in medical research. There are many breeds and colors, the ears may be erect or lop, there are a large number of mammary glands, and they have a characteristic snout, thin skin, and heavy bristles. They are descendants of the wild boar, Sus scrofa. Called also hog. There are many indigenous domesticated breeds. Popular commercial breeds include Berkshire, Chester white, Duroc (Duroc Jersey), Gloucester old spot, Hampshire, Lacombe, Landrace, Large white, Pietrain, Poland China, Tamworth, Wessex saddleback, Yorkshire. Wild genera include wild boar, wild pigs (both Sus spp.), bush pigs (Potamochoerus spp.), wart hog (Phacochoerus aethiopicus), forest hog (Hylochoerus meinertzhageni), babirussa (Babirussa babyrussa). Pigs are becoming popular as companion animals, especially miniature pig breeds.

  • bearded p. (Sus barbatus) a medium-sized, wild pig of Southeast Asia; it has distinctive hairs on the face that form the beard. A meat source for indigenous people.
  • p. ears dried ears (pinnae) marketed as a chew toy for dogs; have been a source of Salmonella infection in humans handling them.
  • miniature p. developed in the early 1960s as research animals by interbreeding local American feral pigs with natural dwarf pigs of Yucatan, Vietnamese, Taiwanese breed origin. Pet pigs called ‘miniature pet pigs’ may be purebred Vietnamese pot-bellied pigs (black, shortnosed, heavy-jowled, pot-bellied, with straight wagging tail), or Yucatan type (straight-bellied, long-snouted, coarse-haired and coarse-coated, without a pot belly and weighing 120–250 lb when mature—called also Mexican hairless), or African Pygmy—called also Guinea hog (with straight back, no pot belly, short- to medium-length hair, kinky tail, black, sometimes with white markings).

• pot-bellied p. not a specific breed; originate from dwarf, pot-bellied indigenous Chinese and South East Asian pigs.

  • p. pox see swinepox.
  • p. typhoid see salmonellosis.

• pig’s ear Cotyledonorbiculata.

• pig-sticking the so-called sport of hunting wild pigs on horseback and stabbing them to death with spears.

• pigCHAMP commercial swine database program produced by University of Minnesota.

• pigeon [pij′ n] a member of the family Columbidae that includes the doves. The domestic pigeons are generally gray, medium-sized, short-legged birds that exist in a large number of breeds and races including Romans, Jacobins, tumblers, fantails, pouters, racing pigeons, and turtle-doves.

  • p.-breeder’s lung see bird-fancier’s lung.

    P-46.

    

    Pot-bellied pig

  • carrier p. pigeon with strong homing instincts used to carry messages over relatively long distances. Produced by breeding and selection between races of domestic pigeons. See also homing pigeon and racing pigeon (below).
  • domestic p. subspecies of pigeon domesticated over 10,000 years ago, known as Columba livia domestica.
  • p. circovirus the cause of lethargy, respiratory, and gastrointestinal signs and poor racing performance in young pigeons.
  • p. fever deep-seated abscesses in the pectoral muscles of horses. See pectoral abscess.
  • p. herpesvirus the cause of respiratory disease (coryza) in domestic pigeons.
  • homing p. pigeon with strong homing instincts used in racing and as a carrier pigeon (above). Produced by breeding and selection between races of domestic pigeon.
  • p. pox see pigeonpox.
  • p. toed a condition in which the toes are turned inward.
  • racing p. breed of domestic pigeon use in pigeon racing.

• pigeonberryDuranta erecta.

• pigeonpox a disease caused by a poxvirus in the genus Avipoxvirus; characterized by the presence of pox lesions in the mouth and serious involvement of the eyes that may be sufficiently serious as to cause blindness.

• pigeonwood see Hedycarya arborea.

• piggery condensate the liquid or dried condensate that collects on walls of piggeries in very cold climates; may be toxic because of its high nitrate content.

• piglet baby pig from birth to conventional weaning age, usually 8 weeks but now more commonly 3 weeks.

  • p. anemia see iron nutritional deficiency.
  • hysterectomy-derived p. see HYPAR.

• pigment [pig′m nt] 1. any coloring matter of the body. 2. a stain or dyestuff. 3. a paint-like medicinal preparation applied to the skin.

  • abnutzen p. see lipofuscin.
  • age p. lipofuscin.
  • bile p. any one of the coloring matters of the bile, derived from heme, including bilirubin, biliverdin, etc.
  • blood p. any one of the pigments derived from hemoglobin, including heme, hematoidin, hermosiderin, etc.
  • p. cells see melanocyte.
  • p. genes genes for each of the coat colors, e.g., white gene, black gene, orange gene.
  • respiratory p’s substances, e.g., hemoglobin, myoglobin, or cytochromes, which take part in the oxidative processes of the animal body.

• pigmentary [pig′m n-tar″e] pertaining to or emanating from pigment.

  • p. incontinence a histopathological lesion in which melanin granules are free in the dermis and within dermal macrophages; it is associated with damage to the stratum basale and basement membrane of the epidermis.

• pigmentation [pig″m n-ta′sh n] the deposition of coloring matter; the coloration or discoloration of a part by a pigment. See also hyperpigmentation, hypopigmentation, melanosis.

  • bacterial p. production of pigment is a characteristic of some bacteria that may be useful in identification. Examples are Pseudomonas aeruginosa, Chromobacterium violaceum and Serratia marcescens.
  • p. disorders see hyperpigmentation, leukoderma, leukotrichia, hypopigmentation.
  • hematogenous p. pigmentation produced by accumulation of hemoglobin derivatives, such as hematoidin or hemosiderin.

• pigmented [pig′m n-t d] colored by deposit of pigment.

• pigmentolysin a lysin that destroys pigment.

• pigmentophage any pigment-destroying cell, especially such a cell of the hair.

• pigweed Amaranthus spp., Portulaca oleracea (inland pigweed), Trianthema portulacastrum (black or giant pigweed).

• PIH prolactin-inhibitory hormone.

• piitis [pi-i′tis] inflammation of the pia mater.

• pika (Ochotona spp.) small lagomorphs in the family Ochotonidae, native to Asia and North America, normally found in mountainous regions. They are herbivorous with short tails and dense fur. Also called rock rabbits or mouse hares.

• pike a freshwater fish in the genus Esox. Includes northern pike (E. lucius).

  • p. fry rhabdovirus an RNA rhabdovirus that is pathogenic to pike and some other fish species

• pike-perch important food fish in Europe and the USSR, including Lucioperca, Perca, and Sander (formerly Stizostedion) spp. See also walleye (4).

• pila [pi′l ] pillar, e.g., pila coronaris dorsalis—one of the several pillars in the rumen that divides it into semiseparate sacs.

• pilar, pilary [pi′l r] pertaining to the hair or to bacterial flagella, as in pilar antigens.

  • p. cyst trichilemmal cyst.

• pilary canal [pil′ -re] lumen of the hair follicle.

• pili [pi′li] plural of pilus.

  • p. torti curvature of the hair follicle results in twisted, flattened hairs; may be caused by systemic disease or inflammation of the hair follicle. Reported in dogs and cats.

• pill [pil] a small globular or oval medicated mass to be swallowed; a tablet.

  • enteric-coated p. one enclosed in a substance that dissolves only when it has reached the intestine.

• pillar [pil′ r] a supporting column.

• p’s of the fauces two paired folds of mucous membrane–coated muscle at the sides of the throat; the palatoglossal arches (the anterior pillar) and the palatopharyngeal arches (the posterior pillar).

  • p. reins short reins attached to each side of a horse’s headstall and fixed to a pillar on each side of the horse, the ties at 5 ft above the ground and the pillars 3 ft apart; method of restraint while grooming or saddling a horse.
  • ruminal p. fleshy ridges that circle the rumen dividing it into dorsal and ventral sacs; lesser coronary pillars demarcate the caudal sacs. Called also pila longitudinalis dextra, pila longitudinalis sinistra, pila accessoria dextra, pila accessoria sinistra, pila coronaria dorsalis, pila coronaria ventralis, pila cranialis pila caudalis.

• pillory [pil′ r-e] a contrivance of pipe or wood that fits around the neck of the cow and stops the head from getting loose, but allows it to move up and down. Called also yokebail.

• pil(o)- word element. [L.] relationship to hair, composed of hair.

• Pilobolus a fungus that grows prolifically on cow feces and facilitates the spread of lungworm larvae by projecting them up to 10 ft when the fungal sporangia explode, as they do when they ripen.

• pilocarpine [pi″lo-kahr′pēn] a cholinergic alkaloid from leaves of Pilocarpus jaborandi and P. microphyllus; used topically as an ophthalmic miotic to treat open-angle glaucoma, and as a lacrimostimulant in the treatment of keratoconjunctivitis sicca.

• pilocystic [pi″lo-sis′tik] hollow or cyst-like, and containing hair; said of dermoid tumors.

• piloerection [pi″lo-e-rek′sh n] erection of hair by arrector pili muscles; functions in thermoregulation, emptying of sebaceous glands and providing social signals. In some species, most noticeable on the neck and along the back (see hackles).

• pilojection introduction of one or more hairs into an aneurysmal sac, to promote formation of a blood clot.

• pilomatricoma [pi″lo-ma″trľ-ko′m ] pilomatrixoma.

• pilomatrixoma [pi″lo-ma″trik-so′m ] a benign, circumscribed, calcifying epithelial neoplasm derived from hair matrix cells, manifested as a small firm, partly calcified intracutaneous spheroidal mass. Kerry blue terriers are predisposed to develop these. Called also epithelioma of Malherbe, calcifying epithelioma.

• pilomotor [pi″lo-mo′t r] causing movement of the hairs, piloerection; pertaining to the arrector pili muscles.

  • p. nerves the nerves supplying the arrector muscles of the hair.

• pilonidal [pi″lo-ni′d l] having a nidus of hairs.

  • p. sinus see dermoid cyst.

• pilose [pi′lōs] hairy; covered with hair.

• pilosebaceous [pi″lo-s -ba′sh s] pertaining to the hair follicles and sebaceous glands.

  • p. follicle sebaceous glands empty into the pilary canal.

• pilot trials preliminary trial using a small number of animals to obtain general information without necessarily achieving statistical significance.

• pilus pl. pili [L.] 1. a hair. 2. fine, filamentous appendage found on the surface of both gram-negative and gram-positive bacteria, shorter and thinner than a flagellum. May play roles in bacterial conjugation, in secretion of bacterial proteins involved in virulence and in adherence of bacterial cells to epithelial surfaces. Composed of polymerized pilin proteins. Adherence is mediated by a separate adhesin protein on the tip of the pilus. Antipilus antibody can provide protection against disease. Called also fimbriae. See also secretion.

  • p. cuniculatus burrowing hair.
  • p. incarnatus ingrown hair.
  • p. lanei wool fiber.
  • p. tacti tactile hairs about the lips, nostrils, and eyes.
  • p. tortus twisted hair; see also pili torti.

• pimecrolimus an immunosuppressive agent similar to tacrolimus.

• Pimelea Australian genus of poisonous annual herbs and perennial shrubs in the family Thymelaeaceae; contain irritant diterpenoids; cause two major syndromes: (1) Pimelea poisoning of cattle, called also St. George disease or Marree disease, caused only in cattle only by a diterpenoid ester, simplexin; the syndrome is one of chronic, right-sided heart failure leading to hydrothorax, massive anasarca and jugular vein distention plus profound anemia and persistent diarrhea; (2) in species other than cattle the only sign is severe diarrhea and a fatal outcome. All species are considered toxic; those with most impact on animal health include P. decora (Flinders poppy), P. elongata, P. haematostachya (pimelea or red poppy), P. latifolia (P. altior), P. microcephala, P. neo-anglica, P. pauciflora, P. prostrata (Strathmore weed), P. simplex, P. trichostachya. Called also many common names, mostly some variation on riceflower, flaxweed.

• pimelea plants in the genus Pimelea. Includes poison pimelea (P. pauciflora).

• pimelitis [pim″ -li′tis] inflammation of the adipose tissue.

• pimelosis [pim″ -lo′sis] 1. conversion into fat. 2. obesity. 3. accumulation or proliferation of fatty tissue.

• pimobendan phosphodiesterase inhibitor used in dogs for its positive inotropic effect and vasodilation in the management of preclinical myxomatous mitral valve disease, clinical congestive heart failure, and dilated cardiomyopathy. See inodilator.

• pimozide butyrophenone tranquilizer in humans; has been used for its long-acting central antiemetic effect in dogs.

• Pimpinella [pim″pľ-nel′ ] genus of plants in family Apiaceae; includes P. anisum. See anise.

• pimple [pim′p l] slang term for pustule.

• pimply gut see esophagostomiasis.

• pin [pin] a slender, elongated piece of metal used for securing fixation of parts.

  • p. bone the triangular ischial tuber; a term used almost exclusively in cattle.
  • p. cutter a sophisticated, surgical version of a bolt-cutter, usually with multiple scissor joints.
  • p. drill a sterilizable drill chuck can be fitted to a surgical power drill and fitted with a surgical bit to match plating screws or orthopedic pins.
  • intramedullary p. see internal skeletal fixation.
  • Steinmann p. a metal rod for the internal fixation of fractures. See also Steinmann pin.
  • p. teat inverted nipple, seen mostly in sows.
  • p. toes toes turned inward. Called also pigeon toes.
  • transarticular p. a pin placed across the articular surfaces of a joint. Most commonly used to stablize hip luxation in dogs and cats.
  • p. vise a device for attaching to the end of an intramedullary pin to provide a grip for placement in bone. See also chuck.

• pin cherry Prunuspennsylvanica.

• pincement [Fr.] pinching of the flesh in massage.

• Pincer emasculatome [pin′s r] see Burdizzo emasculatome.

• pinch biopsy [pinch] a method for gastrointestinal biopsy using forceps, introduced by endoscopy, to grasp and cut small specimens of mucosa and lamina propria.

• pinch method [pinch] a method of correcting entropion in which forceps are used to crush enough skin of the lower lid to correct the abnormal position; it is then cut away and the defect sutured. Largely replaced now by the more controlled Hotz-Celsus procedure pindan poison Velleia panduriformis.

• pindborg tumor [pind′borg] see calcifying epithelial odontogenic tumor.

• pindolol [pin′d -lol] a partial β-agonist used to treat aggression in dogs.

• pindone [pin′dōn] one of a series of 2-aryl-1,3-indandiones that have potent anticoagulant activity. Can cause fatal hemorrhage in animals.

• pine [pīn] 1. unthriftiness of calves due to nutritional deficiency of copper. There is a stiff gait, painful joints, graying of the haircoat, and diarrhea in some. May also be used to describe the unthriftiness caused by nutritional deficiency of cobalt. 2. trees in the genus Pinus. Many other trees are also called pine incorrectly, e.g., cypress pine, milky pine. Includes loblolly pine (P. taeda), ponderosa, western yellow or yellow pine (P. ponderosa), radiata pine (P. radiata).

  • p. needle abortion see pine needle abortion.
  • p. oil an extract from pine trees that is used as an astringent, antiseptic, antitussive, and in cattle, as an antifoaming agent to treat bloat.

• pineal [pin′e- l] 1. shaped like a pine cone. 2. pertaining to the pineal body.

  • p. body, p. gland a small, conical endocrine gland attached by a stalk to the dorsal wall of the third ventricle of the cerebrum. In certain amphibians and reptiles, the gland functions as a light receptor. In most mammals, including humans, it appears to be the major or unique site of melatonin biosynthesis. The effect of melatonin on the body and the exact function of the pineal body remain uncertain. There is an increasing body of evidence that the pineal body is inhibitory to the gonads and that it is the principal mechanism in the known effect of environmental illumination on estrous cycles. It is proposed that the retina perceives the changes in light intensity and stimulates the pineal gland via the sympathetic nervous system.
  • p. extract see melatonin.
  • p. eye in nonmammalian vertebrates, the pineal body is a third or pineal eye.
  • p. gland see pineal body (above).

• pinealism [pin′e- l-iz- m] the condition due to deranged secretion of the pineal body.

• pinealoblastoma [pin″e- -lo′blas-to′m] pinealoma in which the pineal cells are not well differentiated.

• pinealocyte [pin′e- -lo-sīt″] an epithelioid cell of the pineal body.

• pinealoma [pin″e- -lo′m] a rare tumor of the pineal body composed of neoplastic nests of large epithelial cells; it may cause hydrocephalus, precocious puberty, and gait disturbances.

• pinene [pi′nēn] the principal component of turpentine oil.

• ping clear, sharp, high-pitched, metallic, musical note created by a flicking percussion stroke over a viscus containing gas under moderate pressure and a small amount of fluid; used extensively in the physical examination of the abdomen in cattle and horses.

• pingue [ping-gwě] Hymenoxys richardsonii; called also Colorado rubberweed.

• piniform [pin′ľ-form] conical or cone-shaped.

• pining [pīn′ing] the state of having pine (1).

• pinion rear section of a bird’s wing; holds the flight feathers.

• pinioning a permanent alteration of a bird to prevent its flying. The standard operation is amputation of the distal wing including the carpal, metacarpal, and phalangeal bones of one wing. Alternative procedures are tenotomy and ankylosis of a joint. Pinioning is restricted in some countries.

• pink disease [pink] pink color of tissues in broiler chickens dying of fatty liver and kidney disease that responds to dietary supplementation with biotin. Called also fatty liver kidney syndrome.

• pink-eyed coat color series the p allele series causes dilution mainly of dark colors, loss of retinal pigmentation, and sometimes male sterility.

• pink nose [pink] Lantana poisoning.

• pink rot [pink] see fleece rot.

• pink rot fungus of celery Sclerotinia spp.; of parsnip Ceratocystis spp.

• pink slime disparaging slang term for lean finely textured beef with fat removed a treated with ammonium-hydroxide or citric acid and used as an additive to ground beef and processed meats.

• pink tooth [pink] see pink teeth.

• pinkeye [pink′i] see infectious bovine keratoconjunctivitis, contagious ophthalmia (sheep and goats).

• pinky syndrome vitiligo. See also Arabian fading syndrome.

• pinna [pin′ ] the projecting part of the ear lying outside the head; auricle.

• pinnal [pin′ l] pertaining to or emanating from the pinna, e.g., pinnal alopecia. See also auricular, ear.

  • p. cartilage see auricular cartilage.
  • p. fissure see ear fissure.
  • p. pedal reflex see pinnal pedal reflex.

• pinnate [pin′ t or pin′āt] featherlike; said of a muscle in which the fibers lie at angles to its tendon. The fibers may be unipinnate, bipinnate, etc.

• pinnation in a pinnate muscle, the way in which the muscle fibers are attached to its tendon.

• pinning a method of bone fixation, usually for treatment of fractures, in which metal pins are placed within the medullary cavity or anchored in bone. Two types of pin in common use are Steinmann and Rush. See also internal skeletal fixation.

• pinniped member of the mammal superfamily of Pinnipedia, the seals, sea lions, walruses. They are semi-aquatic with sleek, fishlike bodies covered with fur and four limbs modified to flippers. Seals in the family Phocidae do not have external ears, while sea lions and fur seals in the family Otariidae have external ears, and their rear flippers turn forward allowing better movement on land.

• pinocyte [pin′o-, pi′no-sīt] a cell that exhibits pinocytosis.

• pinocytosis [pin″o-, i″no-si-to′sis] a mechanism by which cells ingest extracellular fluid and its contents; it involves the formation of invaginations by the cell membrane, which close and break off to form fluid-filled vacuoles in the cytoplasm. Occasionally also referred to as fluid-phase endocytosis.

• pinosome [pin′o-, pi′no-sōm] the small, fluid-filled intracellular vacuole formed in the process of pinocytosis.

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  Pinto horse

• pinscher a general term that could refer to any of several breeds, including Affenpinscher, Doberman pinscher, German pinscher, or Miniature pinscher.

• pint [pīnt] a unit of liquid measure in the apothecaries’ system, 16 fluid ounces. The Imperial pint is 568.26 ml and the American liquid pint is 473.17 ml.

• Pinta fever [pēn′tah] see Rocky Mountain spotted fever.

• pinto a broken-colored or paint horse used for riding. See also piebald, skewbald. See also American Paint horse.

• Pinus [pi′n s] a genus of coniferous trees in the family Pinaceae.

  • P. ponderosa, P. contorta, P. radiata the leaves of the trees P. ponderosa (ponderosa pine), P. jeffreyi (jeffery pine). P. contorta (lodgepole pine), and P. radiata (monterey pine) contain isocupressic acid and are abortifacient when fed to cows. See pine needle abortion.
  • P. taeda the leaves are reported to cause fatal indigestion in cows. Called also loblolly pine.

• pinworm [pin′werm] any oxyurid, especially Oxyuris equi and Probstmayria vivipara both in horses, Passalurus ambiguus in rabbits, Syphacia obvelata in hamster and mouse.

• Pinzgau a multipurpose breed of central European cattle, red-brown color, colorsided, colored head. Called also Pinzgauer.

• Pinzgauer 1. Pinzgau cattle. 2. Noric horse.

• Piophila casei the cheese or ham fly. The larvae are the skippers of neglected food. They leap around when they are looking for a dry spot to pupate.

• pipecurium pipecuronium.

• pipecuronium bromide [pip″ -ku-ro′ne- m] a long-acting, non-depolarizing neuromuscular blocking agent similar to tubocurarine.

• pipemidic acid a quinolone antibiotic, similar to nalidixic acid, being effective primarily against gram-negative bacteria.

• piperacetazine a phenothiazine tranquilizer used as a sedative and antipruritic (antihistaminic) agent.

• piperacillin [pi-per′ -sil″in] an extended-spectrum semisynthetic penicillin active against a wide variety of gram-negative, gram-positive, aerobic and anaerobic bacteria, including Pseudomonas aeruginosa.

• piperazine [pi-per- -zēn] an anthelmintic; several of its salts are used, especially in horses and dogs. A useful agent especially against ascarids. Combined with a benzimidazole is effective against Parascaris equorum and benzimidazole-resistant small strongyles. Piperazine is a very safe medicament but poisoning occurs in doses that are several times normal. Signs include incoordination, pupillary dilatation, hyperesthesia, somnolence, tremor, swaying at rest, and recumbency. Spontaneous recovery usual.

• piperidine alkaloids include coniine, cynapine, lobeline, nicotine.

• piperocaine [pi′p r-o-kān″] a local anesthetic, used as the hydrochloride salt.

• piperonyl butoxide [pi-pur′o-n l] a synergist used with, and as an enhancer for, pyrethrum and rotenone in the control of ectoparasites.

  P-48.

  

  Pinzgau dual-purpose cow

• pipestem long, thin, firm and rounded like the stem of a pipe.

  • p. feces loose feces passed as long tube-like stools through a stenotic or undilated sphincter.
  • p. liver bovine liver with the calcified, fibrosed bile ducts of chronic fascioliasis.

• pipet [pi-pet′] pipette.

• pipette [pi-pet′] [Fr.] 1. a volumetrically accurate glass or transparent plastic tube used in measuring or transferring small quantities of liquid or gas. 2. to dispense by means of a pipette.

• Pipturus argenteus toxic plant in the family Urticaceae; an unidentified toxin causes diarrhea, dyspnea, recumbency.

• pirbuterol [pir-bu′t r-ol] a synthetic β-receptor agonist, used as the acetate or hydrochloride salt in the treatment of bronchospasm (e.g., asthma, equine recurrent airway obstruction).

• pirenzepine [pir″ n-zě′pēn] a selective M₁ cholinergic antagonist; used in treatment of gastric ulcers in dogs.

• piriform [pir′ľ-form] pear-shaped.

• pirimiphos an heterocyclic organophosphate compound used in ear tags for control of horn flies and face flies on cattle.

• piritrexin see tetroxoprim.

• pirlimycin a lincosamide antibiotic active against gram-positive bacteria. Used as an intramammary infusion for clinical and subclinical mastitis in cattle.

• Piroplasma [pi″ro-plaz′m ] an invalid generic name; see Babesia, Theileria.

• piroplasmosis [pi″ro-plaz-mo′sis] see babesiosis.

  • equine p. caused by Babesia caballi and B. equi affecting horses, donkeys, mules, and zebras; transmitted from carrier animals via tick bites or through mechanical transmission by improperly disinfected needles or surgical instruments. Infection may be inapparent or manifest with signs including fever, anemia, hemoglobinuria, jaundice, dyspnea, and colic. Infection is present in most regions including, recently, North America.

• piroxicam [pir-ok′sľ-kam] a nonsteroidal anti-inflammatory agent with antineoplastic activity, as well as being an effective analgesic; used in the treatment of transitional cell carcinoma in dogs.

• Piry virus a rhabdovirus in the genus Vesiculovirus, a possible human pathogen.

• Piscinoodinium see Oodinium.

• Piscirickettsia salmonis obligately intracellular gram-negative bacterial pathogen of fish. A member of the class Thiotrichales in the class Gammaproteobacteria.

• piscirickettsiosis name of a disease caused by Piscirickettsia an intracellular bacteria. In salmonids, Piscirickettsia salmonis has been associated with severe losses in the aquaculture industry in Chile. See also rickettsial fish disease.

• piscivorous [pi-siv′ -r s] fisheating; said of birds.

• pisiform [piz′ľ-form] 1. resembling a pea in size and shape. 2. the accessory carpal bone.

• Pistacia spp ingestion of leaves suspected to cause acute hemolytic anemia characterized by red urine, jaundice, anemia, and methemoglobinemia in horses. Called also mastic tree, pistache.

• pistol a weapon for delivery of a missile, usually a weapon to fire a bullet, used in euthanasia see captive bolt pistol.

  • balling p. a device shaped like a pistol but loaded with a medicinal bolus that is fired into the pharynx of a horse by the operation of a spring loaded piston.

• Pisum [pi′s m] a genus of plants in the legume family Fabaceae; an unidentified toxin causes lameness, incoordination, recumbency; deranged behavior has occurred in cattle grazing field peas; includes P. sativum (garden pea), P. sativum var. arvense (field pea or Austrian pea).

• pit [pit] 1. a hollow fovea or indentation. 2. a pockmark. 3. to indent, or to become and remain for a few minutes indented, by pressure. 4. seed of a fruit, e.g., cherry. Strictly refers to the hard woody coating that surrounds the seed.

  • anal p. the proctodeum of the embryo.
  • auditory p. a distinct depression in each auditory placode, marking the beginning of the embryonic development of the internal ear.
  • lens p. a pit-like depression in the fetal head where the lens develops.
  • nasal p. a depression appearing in the olfactory placodes in the early stages of development of the nose. Called also olfactory pit.
  • occlusal p. indentation on the occlusal surface of a tooth, such as a molar.
  • olfactory p. see nasal pit (above).
  • otic p. early stage in the development of the embryonic inner ear.
  • p. of stomach the epigastric fossa or epigastric region.

• pit bull a common term describing a type of small- to medium-sized, short-haired muscular dog with a powerful head and jaws. Usually associated with aggression toward other dogs and humans. Breeds commonly included in this stereotype are American pit bull and Staffordshire bull terrier.

• pitch [pich] 1. a dark, more or less viscous residue from distillation of tar and other substances. 2. natural asphalt of various kinds. 3. the quality of sound dependent on the frequency of vibration of the waves producing it.

  • coal tar p. see coal tar pitch.

• pitchblend a black mineral containing uranium oxide; from it are obtained radium, polonium, and uranium.

• pitchery Duboisiahopwoodii.

• pith [pith] soft, spongy, plant tissue.

• pithecoid [pith′ -koid] apelike.

• pithing [pith′ing] 1. destruction of the brain and spinal cord by thrusting a blunt needle into the vertebral canal and cranium, done on animals to destroy sensibility preparatory to experimenting on their living tissue. 2. an abattoir method of euthanasia; the animal is stunned by a captive bolt pistol, and a cane or coiled wire passed into the cranium through the hole. The brain is destroyed by moving the cane about.

• Pithomyces chartarum [pith″o-mi′sēz] previously called Sporidesmium bakeri. Produces the mycotoxin sporidesmin, which causes facial eczema.

• pithomycotoxicosis [pith″o-mi″ko-tok″sľ-ko′sis] liver damage caused by the toxins of Pithomyces chartarum. See also facial eczema.

• pitis pitis see Sarcolobus globosus.

• Pitressin [pľ-tres′in] trademark and commonly used name for a preparation of vasopressin.

  • P. tannate test see antidiuretic hormone response test.

• pitting [pit′ing] 1. the formation, usually by scarring, of a small depression. 2. the removal from erythrocytes, by the spleen, of such structures as iron granules, without destruction of the cells. 3. remaining indented for a few minutes after removal of firm finger pressure.

• pituicyte [pľ-too′ľ-sīt] any of the distinctive fusiform cells comprising most of the neurohypophysis.

• pituicytoma [pľ-too′ľ-sīt-o″m ] a neoplasm of the neurohypophysis.

• pituitary [pľ-too′ľ-tar″e] 1. a neuroepithelial endocrine gland of dual origin at the base of the brain in the sella turcica, attached by a stalk to the hypothalamus; called also hypophysis. It is composed of two main lobes, the anterior lobe (anterior pituitary, adenohypophysis), secreting several important hormones that regulate the proper functioning of the thyroids, gonads, adrenal cortex, and other endocrine glands, and the posterior lobe (posterior pituitary, neurohypophysis) whose cells serve as a reservoir for hormones having antidiuretic and oxytocic action, releasing them as needed, and in response to signals from the hypothalamus, itself responding to incoming signals from the nervous system received by the thalamus. Called also hypophysis. See also pituitrin, vasopressin, oxytocin, antidiuretic hormone, thyrotropin releasing hormone, adrenocorticotropic hormone, follicle-stimulating hormone, luteinizing hormone, melanocyte-stimulating hormone, prolactin, and growth hormone. 2. pertaining to the pituitary gland. 3. a preparation of the pituitary glands of animals, used therapeutically.

  • p. abscess abscess in the rete mirabile of the pituitary is recognizable clinically in cattle. The syndrome begins with a characteristic inability to close the mouth. Saliva drools, the tongue is prolapsed slightly, and there may be blindness, opisthotonos, loss of balance, and recumbency.
  • p.–adrenal axis the interactions between hypothalamus, pituitary, and adrenal cortex, involving releasing factors, tropic hormones, and negative feedback mechanisms.
  • p. alopecia see alopecia X.

    P-49.

    

    Lobes of the pituitary gland

  • p. cachexia see pituitary cachexia.
  • p. dwarfism congenital dwarfism with all parts properly proportioned. Affected animals are miniatures of normals. There is delayed bone development and epiphyseal fusion is retarded. It is inherited in cattle and several breeds of dogs. See also German shepherd dog dwarfism.
  • p. giantism acromegaly.
  • p. gonadotropins follicle-stimulating hormone, luteinizing hormone.
  • fetal p. hormones in sheep, cows, and goats fetal pituitary ACTH stimulates fetal adrenal cortisol production, inducing in turn placental estrogen secretion. Hence fetal placental hormone is important in the induction of parturition.
  • p. hypoplasia congenital absence (aplasia) or incomplete growth (hypoplasia) of gland. Occurs in one form of inherited prolonged gestation in cattle and in poisoning by the weed Salsola tuberculata var. tomentosa. It is an inherited trait in German shepherd dogs.
  • posterior p. 1. the posterior lobe of the pituitary gland; the neurohypophysis. 2. a preparation of animal posterior pituitary having the pharmacological actions of its hormones, oxytocin, and vasopressin; used mainly as an antidiuretic in the treatment of diabetes insipidus and as a vasoconstrictor.
  • p. rete mirabile abscess see pituitary abscess.
  • p. tumor includes adenoma, carcinoma, and craniopharyngioma. All cause pressure on surrounding tissue and some cause endocrinological disturbances.
  • p. pars intermedia dysfunction see equine pituitary pars intermedia dysfunction.

• Pituitrin proprietary name of an extract of bovine pituitary gland containing oxytocin and vasopressin, now displaced by synthetic preparations containing only one of these hormones.

• Pituranthos triradiatus see Deverra triradiata.

• pituri, pitury Duboisiahopwoodii.

• pityriasis rosea [pit″ľ-ri′ -sis] a disease of pigs, most commonly white breeds such as Landrace, up to 3 months old characterized by circular lesions 1 in. (2–3 cm) diameter that often coalesce to produce large irregular lesions. The central area of the lesion is an area of comparatively normal skin, covered by thin brown scales and surrounded by a very narrow, 1- to 2-mm raised zone of erythema. There is no irritation or no bristle loss and spontaneous recovery is usual. The etiology is unknown. Called also porcine juvenile pustular psoriasiform dermatitis, pseudoringworm.

• pityroid [pit′ľ-roid] furfuraceous; branny; resembling pityriasis.

• Pityrosporon [pit″ľ-ros′p -ron] see Malassezia.

• pivalate [piv′ -lāt] USAN contraction for trimethylacetate, an ester used in the manufacture of certain drugs.

• pivamdinocillin [piv-am″pľ-sil′in] an ester of amdinocillin. Called also pivmecillinam.

  P-50.

  

  Pityriasis rosea

• pivampicillin an ester of ampicillin with the same broad spectrum of antibiotic activity.

• PIVKA proteins induced by vitamin K deficiency or antagonists; nonfunctional precursor forms of vitamin K–dependent coagulation factors, lacking carboxylation of glutamic acid residues, found in animals treated or poisoned with anticoagulants. The inactive precursors that accumulate in the circulation are called Proteins Induced by Vitamin K Antagonism or Absence (PIVKA).

• pivmecillinam [piv″m -sil′ľ-n m] pivamdinocillin, an antibacterial drug in the β-lactam group.

• pivoters a term used in the meat industry for animals that walk in circles.

• pivoting said of the exercise demanded of a horse when testing a limb for weakness or lameness; the horse is forced to turn very tightly so that it actually pivots on the limb being examined.

• pixel [pik′sel] a picture element such as a dot on a video or computer display screen. The greater the concentration of pixels the clearer the image. The total number of pixels elements is specified in megapixels (1 megapixel=1 million pixels). A computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET) scan image is composed of an array of pixels each of which is colored a uniform shade of gray or another color representing the data from a voxel.

• Pixiebob a medium to large cat developed in northwestern US. With a long or short, thick, wooly coat with tabby markings and a bobtail, they resemble the wild bobcat in the area. Polydactyl.

• pizzle [piz′ l] 1. prepuce. 2. penis.

  • p. dropping a farm procedure used in male sheep to reduce local wetting of the wool as a prevention against pizzle rot. The anterior attachment of the prepuce to the abdominal wall is severed.
  • p. rot see enzootic balanoposthitis.
  • p. stain wool stained by urine; in belly wool from male sheep.

• PK pyruvate kinase.

• pK the negative logarithm of the ionization constant (K) of an acid, the pH of a solution in which half of the acid molecules are ionized.

• PKU phenylketonuria.

• placebo [pl -se′bo] [L.] a substance given to a patient as medicine or a procedure performed on a patient that has no intrinsic therapeutic value but meets the owner’s expectation that some form of treatment is being given. A placebo may be administered in the form of a sugar pill or an injection of sterile water. Placebos are also used in randomized, placebo-controlled clinical trials (RPCCTs or RCTs) of new drugs. While some patients selected at random are given the new drug, others are given an identical appearing placebo. In double-blinded RCTs, neither the owners nor the researchers know which patients are receiving the study drug. The patients taking the study drug must show significantly greater relief of clinical signs than the control group taking the placebo for the new drug to be considered effective. Placebos can produce an effect that is positive, with improvement of signs; neutral, with no change in clinical signs; or negative, with worsening of signs or the appearance of adverse side effects.

• placenta [pl -sen′t] pl. placentae, placentas [L.] an organ characteristic of true mammals during pregnancy, joining mother and offspring, providing endocrine secretion and selective exchange of soluble bloodborne substances through apposition of uterine and trophoblasticvascularized parts. Called also afterbirth. See also fetal membranes, placentation. Domestic animals have a chorioallantoic placenta in which the outer layer of the allantois is fused with the chorion, and the fetal umbilical vessels are distributed in the connective tissue between the two. Placentae are classified in several ways; based on the tissues of the dam and the fetus that contact each other; based on the proportion of the surface area of the fetal membranes that is in fact placentacious; based on loss of tissue at birth, etc., Thus, the bovine placenta is epitheliochorial, cotyledonary, and nondeciduate. The major function of the placenta is to allow diffusion of nutrients from the dam’s blood into the fetus’s blood and diffusion of waste products from the fetus back to the dam. This two-way exchange takes place across the placental membrane, which is semipermeable. The placenta also produces hormones such as progesterone and estrogen.

  P-51.

  

  Placenta types based on distribution of contact areas between fetal and maternal components

  P-52.

  

  Retained placenta (fetal membranes)

  • adeciduate p. see epitheliochorial placenta (below).
  • choriovitelline p. a placentation in which the yolk sac becomes involved in the fetal–maternal union.
  • cotyledonary p. distribution of the villi on the fetal chorion is localized in multiple circumscribed areas—the cotyledons.
  • diffuse p. the villi on the fetal chorion is diffuse over the entire placenta as in mares and sows.
  • discoid p. a placenta in which the chorionic villi are arranged in a circular plate as in human and rodent placentae.
  • endotheliochorial p. the maternal vessels in the endometrium are bared to their endothelium, and these are in contact with the chorion of the fetal membranes. This occurs in the bitch and queen.
  • epitheliochorial p. the uterine epithelium and the chorion are in contact, and there is no erosion of the epithelium. Characteristic of cows, sows, and mares. Called also adeciduate placenta.
  • hemochorial p. a type of placenta in which all maternal layers are lost so that fetal tissue is in contact with frank maternal blood, as occurs in insectivores, rodents, rabbits, and most primates.
  • nondeciduate p. no maternal tissue is lost when the pregnancy terminates.
  • retained p. the placenta has not been passed within a certain time (cow 12 hours, sheep and goat 6 hours, mare 8 hours, camelid 3 hours) after the fetus has been delivered. Represents a potential beginning for metritis and infertility. Often difficult to assess in carnivores as they rapidly eat the placenta, but of less concern than in other species. Called also retained fetal membranes.
  • syndesmochorial p. a type of placentation characterized by an endometrial attachment to the chorion with a limited amount of destruction of the endometrial epithelium. Formerly thought to be characteristic of the ewe and goat doe, these species are now known to have epitheliochorial placentae.
  • zonary p. a placenta in which the chorionic villi are restricted to an equatorial girdle, as in the bitch and queen.

• placental [pl -sen′t l] pertaining to or emanating from placenta.

  • p. barrier the placental separation of maternal and fetal blood that varies in its structure and permeability between the species. In general, the more layers of cells between the two circulations, the less permeable the membrane. In none of the domestic animals are significant amounts of immune globulins or erythrocyte antigens passed through the membranes unless the epithelium is damaged. See also placenta.
  • p. calcification accumulations of mineral deposit especially around the vessels and in the allantois, a normal occurrence in most species.
  • p. cavities the allantoic and amniotic cavities; called also amniotic and allantoic sac.
  • p. edema edema of the placenta, without necessarily any involvement of the fetus.
  • p. hormones the placenta in all species produces estrogens and progesterone. In the cow it also produces lactogen, a hormone that influences structural and functional aspects of milk production. In the mare, the endometrial cups produce PMSG (now called eCG) that assists in the maintenance of pregnancy. The canine, equine, feline, and primate placentae also produce relaxin that has a similar action.
  • p. implantation the placenta of a viable fetus, escaped from the genital tract, can implant successfully to the peritoneum in some species.
  • p. inflammation see placentitis.
  • p. lactogen a placental hormone present in the cow’s peripheral circulation at about 160 days of pregnancy; thought to have prolactin and growth-hormone capabilities. Used for pregnancy diagnosis in some species. Called also placenta associated glycoprotein (PAG), chorionic somatomammotropin.
  • p. mole see mole.
  • p. plaques are normal structures on the amnion in most species. They are foci of squamous epithelium.
  • p. transfer of immunoglobulins see placental barrier (above) and passive immunity.

• placentation [pla″s n-ta′sh n] 1. the series of events following implantation of the embryo and leading to development of the placenta. 2. the nature of the implantation. See also placenta.

  • adventitial p. developmental of additional areas outside the normal areas, e.g., intercotyledonary in cattle.
  • cotyledonary p. the areas of placentation are limited to caruncles, approximately circular masses scattered over the placenta. Characteristic of the cow, ewe, and goat doe.
  • diffuse p. the whole of the surface of the chorion is placental.
  • intercotyledonary p. abnormal placental attachments between the cotyledons, in cows.
  • zonal p. only some zones of the placenta have a vascular area involved in placentation. Characteristic of the bitch and the queen.

• placentitis [pla″s n-ti′tis] inflammation of the placenta; causes abortion or, by adhesions, retention of the placenta. Infection is hematogenous in most species, but ascending infections are common in mares resulting in inflammation and detachment of the chorioallantois at the level of the cervical star.

  • ascendant p. infection ascends from the vagina through the cervix. Common in mares with abnormal vulvar and vaginal conformation.
  • hematogenous p. infection of the placenta after septicemia.
  • nocardioform p. distinct type of chronic placentitis in mares with the lesion on the chorionic surface of the placenta; caused by Crossiella equi. A proportion of infections result in late-term abortion, stillbirth, or premature birth. Reported only in Kentucky.

• placentography [pla″s n-tog′r -fe] radiological visualization of the placenta after injection of a contrast medium.

• placentoid [pl -sen′toid] resembling the placenta.

• placentome the cotyledon plus the caruncle.

  P-53.

  

  Ascending placentitis viewed from the allantoic surface; note the thickening and discoloration around the cervical star

• placentopathy [pla″s n-top′ -the] any placental disease.

• placentophagia act of ingesting the placenta of their young at parturition; common behavior in carnivores.

• placing the way in which an animal places its feet when moving.

  • p. reflex a postural reaction tested by supporting the animal and approaching a surface such as a table to see how the animal positions its feet; performed with and without a blindfold to test its tactile and visual responses.

• Placobdella freshwater leeches from the family Glossiphoniidae, parasitizing birds, mammals, amphibians, and reptiles, usually feeding on the blood of their host. They generally have a flattened appearance with a small anterior sucker, and some species exhibit parental nurturing. Recorded species include P. rugosa, P. parasitica.

• placode [plak′ōd] a plate-like structure, especially a thickening of the ectoderm marking the site of future development in the early embryo of an organ of special sense, e.g., the auditory placode (ear), lens placode (eye), and olfactory placode (nose).

  • lens p. the ectodermal thickening that develops into the lens vesicle and later the lens.
  • nasal p. one of a pair of ectodermal thickenings that are the forerunners of the external nares and nasopharyngeal epithelium.
  • olfactory p. an ectodermal thickening of the embryo which ultimately provides the sensory nerves for the olfactory region of the nasal mucosa.
  • otic p. one of the pair of ectodermal thickenings in the vertebrate embryo that invaginates and is a major contributor to the internal ear.

• placoid [plak′oid] plate-like or plaque-like.

• Plagiobothrys genus of plants in family Boraginaceae; causes nitrate–nitrite poisoning; called also popcorn flower.

• plagiocephaly [pla″je-o-sef′ -le] bizarre oblique distortion of the shape of the skull resulting from irregular, asymmetrical closure of the cranial sutures.

• Plagiorchis a genus of flukes (digenetic trematodes) in the family Plagiorchiidae.

  • P. arcuatus found in, and causes inflammation of, the oviduct of fowls.
  • P. lutrae found in otters.
  • P. megalorchis (syn. P. laricola) found in turkey poults and in wild birds.

• Plagiorhynchus formosus see Prosthorhyncus formosus.

• plague [plāg] 1. an epidemic of disease attended by great mortality. 2. an acute febrile, infectious, highly fatal disease caused by the bacillus Yersinia pestis. It is primarily a disease of rats and other rodents, dogs, and cats, and is usually spread to humans by fleas. The more common form of plague is the bubonic. There is also a pneumonic type in humans, which can be spread directly from person to person by droplet infection. The clinical signs in all species are fever, vomiting, and enlargement of lymph nodes, the buboes that give the disease its name. See also septicemic plague (below).

  • bubonic p. a highly contagious and severe disease caused by the bacillus Yersinia pestis carried in infected rats and transmitted to humans by fleas. See also plague.
  • cattle p. see rinderpest.
  • duck p. an acute infectious disease of ducks caused by a herpesvirus and characterized by tissue hemorrhages and blood free in body cavities, eruptions on the mucosae of the digestive tract, degeneration of parenchymatous organs and lesions in lymph nodes. Called also duck virus enteritis.
  • equine p. see African horse sickness.
  • fowl p. see avian influenza.
  • septicemic p. hematogenous spread of infection to many organs may occur without the formation of buboes; occurs in the cat with pulmonary involvement, disseminated intravascular coagulopathy, and death.
  • swine p. see swine plague.
  • sylvatic p. bubonic plague in wild animals in uninhabited areas, including wild rats, ground squirrels, mice, marmots, owls, gophers, badgers, rabbits, prairie dogs, and chipmunks that serves as a reservoir for urban rats that are the origin, via the oriental rat flea (Xenopsylla cheopis), of bubonic plague in humans. Caused by Yersinia pestis, plain bodied said of a wool sheep with very few skin wrinkles.

• plainhead in canaries, one with plain feathering on the head instead of a crest. The Australian plainhead, the only canary breed created in Australia, was developed from the Norwich canary.

• plane [plān] 1. a flat surface determined by the position of three points in space. 2. a specified level, as the plane of anesthesia. 3. to rub away or abrade. See also planing and plastic surgery. 4. a superficial incision in the wall of a cavity or between tissue layers, especially in plastic surgery, made so that the precise point of entry into the cavity or between the layers can be determined.

  • coronal p. a plane that passes through the coronal suture (i.e., between the frontal and parietal bones); an ambigulous term that cannot be applied to both quadrupeds and bipeds to denote similar planes of reference. Sometimes called ‘frontal plant’. Fundamentally there are three planes of reference in quadrupeds: the safittal, dorsal, and transverse.

    P-54.

    

    The canine muzzle. 1. Nasal plane; 2. philtrum

  • dorsal p. any plane passing longitudinally through the body from side to side, at right angles to the median plane and dividing the body into dorsal and ventral parts. Also, erroneously called coronal plane, frontal plane.
  • horizontal p. one passing through the body at right angles to the median plane, and dividing the body into upper and lower parts. In quadrupeds, synonymous with dorsal plane; in bipeds, with transverse plane.
  • inclined p. an intraoral acrylic or metal appliance used in orthodontics to guide a tooth into a new position by using pressure applied when the mouth is closed normally. Commonest use is to move canines laterally.
  • median p. one passing longitudinally through the body from front to back and dividing it into right and left halves. See also sagittal plane (below).
  • nasal p. the zone of hairless and nonglandular, usually pigmented (in dogs) skin around the nostrils and around the tip of the nose in carnivores. Called also the planum nasale.
  • nasolabial p. the hairless glandular extension of the nasal plane between the nostrils into the upper lip in cattle. Called also planum nasolabiale.
  • nuchal p. the flat surface at the back of the occipital bone below the nuchal crest.
  • rostral p. the bare glandular area on the snout disc of the pig. Called also planum rostrale.
  • sagittal p. any vertical plane through the body parallel to the median plane (or to the sagittal suture) and dividing the body into left and right portions.
  • transverse p. one passing through the body, at right angles to the sagittal and dorsal planes, and dividing the body into cranial and caudal portions.
  • vertical p. one perpendicular to a horizontal plane, dividing the body into left and right, or front and back portions.

• planigraphy [pl -nig′r -fe] a method of body-section radiography that shows in detail structures lying in a predetermined plane of the body while blurring structures in other planes, produced by movement of the film and x-ray tube in certain specified directions. See also tomography.

• planing [plān′ing] abrasion of disfigured skin to promote re-epithelization with minimal scarring; done by mechanical means (dermabrasion) or by application of a caustic (chemabrasion). See also plastic surgery.

  • root p. smoothing and cleaning surfaces of a tooth root in the treatment of advanced periodontal disease.

• plank method common term for Schaffer method, also called plank-inthe-flank; a method of relieving uterine torsion in cows and occasionally in mares. The patient is cast and laid on her side (direction of the torsion). A plank with a person standing on it is used to put pressure on the abdomen (stabilizing the uterus) while the patient is rolled.

• plankton [plank′ton] a collective name for small animal and plant (phytoplankton) organisms that drift passively in all natural bodies of water. The starting point of the aquatic food chain. Called also microalgae.

• planktonophagous eating or subsisting solely on plankton.

• planned animal health/production program regular visits to farms by a veterinarian to monitor biosecurity and health parameters, especially fertility, cow comfort, lameness, nutrition, and mastitis in dairy herds, and check productivity indexes, e.g., weight gains in beef cattle, followed by reports on achievement relative to targets and the application or recommendation about treatment or preventive measures.

• planoconcave [pla″no-kon′kāv] flat on one side and concave on the other.

• planoconvex [pla″no-kon′veks] flat on one side and convex on the other.

• planography planigraphy.

• Planorbis [pl -nor′bis] a genus of water snail, intermediate hosts to paramphistomes.

• plant [plant] a member of the vegetable kingdom (Kingdom Plantae); living things characterized by cellulose in cell walls, absence of locomotion, absence of special senses, and feeding only on inorganic substances; most are autotrophs using photosynthesis through chlorophyll to acquire energy.

  • abortigenic p. plants that cause abortion include Pinus, Cupressus, and Astragalus spp.
  • p. alkaloids see alkaloid.
  • annual p. one that completes its life cycle within 1 year. A winter annual plant germinates in the fall (autumn), overwinters as a seedling and flowers and seeds in spring. The dominant grazing species in the early spring. Examples would be many mustard weeds of disturbed places incriminated in the congenital hypothyroid dysmaturity syndrome in foals.
  • p. awns sharp, long processes attached to seed casings of plants, mostly grasses; important causes of skin and oral lesions in grazing animals, and to housed animals when fed hay containing the plants.
  • biennial p. one that completes its life cycle in 2 years, generally germinating and growing in the first year and flowering, fruiting, and subsequently dying in the second year.
  • p. eating both dogs and cats may eat grass; indoor animals sometimes eat ornamental plants, some of which are poisonous.
  • p. hormones organic substances produced by plants that are extracted and used as herbicides or plant growth stimulants. Some of them cause long-term ill health in animals if drunk in large quantities.
  • perennial p. one that completes its life cycle over more than 2 years.
  • p. poisoning the list of poison plants is very large, and it is necessary to know the suspect plant’s botanical name to begin an effective search for information about it. In order to exert an effect on an animal, the plant has, in most cases, to be eaten. There are a few plants that exert a toxic effect by inhalation or by skin contact.
  • p. protein the proteins in plants. Common, protein-rich plants include alfalfa, the oilseed meals, e.g., soyabean, cottonseed, and linseed meals, clover, the legume seeds, e.g., peas, beans.
  • teratogenic p. plants that cause congenital defects include Lupinus, Lathyrus, Leucaena, Nicotiana, Conium, Astragalus, Oxytropis, Veratrum, Vicia, Salsola spp.
  • p. toxins phytotoxins, elaborated by plants, in some cases incorporating an inorganic element, e.g., selenocompounds, and in some cases present in the plant in nontoxic state, requiring metabolism to activate it.

• Plantago [plan-ta′go] a large genus of plants in the family Plantaginaceae.

  • P. psyllium a plant whose seeds resemble fleas. Used at one time as a flea repellent. See also psyllium.
  • P. varia a common weed of native pastures providing scant feed. Called also plaintain and sometimes lamb’s tongue.

• plantain two plant species are called by this common name. See Plantago varia.

• plantar [plan′t r] pertaining to the sole or caudal aspect of the digit.

  • p. cushion see digital cushion.
  • p. ligament strong ligaments running down the backs of the hind paws, or the plantar surface of the hock in ungulates. Strain of this ligament results in the condition known as ‘curb’. Called also ligamenta tarsi plantaria, which includes the long plantar ligament, ligamentum plantare longum, and the calcaneocuboid ligament, ligamentum calcaneocuboideum.

    P-55.

    

    Plantigrade posture in a cat with diabetes mellitus and exocrine pancreatic insufficiency

  • p. nerve block see plantar block.
  • plantaris [plan-ta′ris] [L.] 1. plantar. 2. the superficial digital flexor muscle of the hindlimb.

• plantation walk [plan-ta′sh n] the four-beat, running walk gait characteristic of the Tennessee walking horse.

• plant growth regulator chemicals that depress plant growth. May be used as herbicides singly or in combination with other herbicides. Also used for growth suppression, for example, of grass, for suppression of sprouting of vegetables and stored food crops, control of sucker growth on tobacco plants, retardation of flowering, and prolongation of dormancy period.

• plantigrade [plan′ti-grad] a method of locomotion seen in bears, monkeys and humans, in which the animal walks on the phalanges, metacarpal and carpal or tarsal bones, as distinct from digitigrade and unguligrade.

  • p. stance seen in dogs and cats with various neuropathies and myopathies, particularly in diabetic neuropathy and hypokalemic polymyopathy.

• planum pl. plana [L.] plane.

  • p. nasale see nasal plane.
  • p. nasolabiale the plate of moist, highly cornified epidermis, completely hairless, containing tubular merocrine glands around the nostrils and upper lip, which is characteristic of the muzzle of cattle.
  • p. rostrale the front plate of the snout of pigs; highly cornified epithelium, contains many tubular merocrine glands and a few fine hairs.

• plaque [plak] 1. any patch or flat area; in the skin, a flat-topped, elevated lesion. 2. a clear area of cell lysis caused by viral replication on a cell monolayer.

  • amniotic p. small, 2 to 4 mm diameter, epithelial proliferations on the inside (fetal side) of the amnion. Normal structure on the bovine amnion during the middle trimester.
  • annular p. seen in equine lupus erythematosus panniculitis.
  • p. assay a method of quantifying the number of infectious units by inoculating serial dilutions of a viral suspension on a cell culture monolayer, overlaying with a medium containing agarose and after several days incubation, counting the number of plaques formed; recorded as plaque forming units/ml.
  • atheromatous p. a deposit of predominantly fatty material in the lining of blood vessels occurring in atherosclerosis.
  • cutaneous p. an elevated, solid structure without a necrotic center, up to 1–2 in. diameter with an unbroken surface.
  • dental p. a biofilm adhering to the enamel surface of a tooth, composed of a mixed colony of bacteria in an intercellular matrix of bacterial and salivary polymers and remnants of epithelial cells and leukocytes. It is important in the development of caries, dental calculi, and periodontal disease.
  • drug p. cutaneous, subcutaneous or subconjunctival deposits formed as a result of injection of some drugs, particularly repository steroid preparations. May be unsightly and a cause of conjunctivitis.
  • ear p. see ear plaque.
  • eosinophilic p. see eosinophilic plaque.
  • p.-forming units the number of plaques formed in the plaque assay; expressed as pfu/ml.
  • p. index an assessment used in dental charting to record the extent of plaque on the buccal surface of the tooth.
  • pigmented epidermal p. heavily pigmented hyperplastic epidermis seen in dogs and associated with papillomavirus infection. Intranuclear inclusion bodies are seen in lesions that may occur as multiple macules, papules, and plaques. Comparisons have been made with epidermodysplasia verruciformis, a condition in humans.
  • senile p. described in the brain of old dogs.
  • siderotic p. nodules observed as waxy, gray-yellow encrustations on the splenic capsule of old dogs.

• plasm [plaz′ m] 1. plasma. 2. formative substance (cytoplasm, hyaloplasm, etc.).

• plasma [plaz′m ] the fluid portion of the blood in which corpuscles are suspended. Plasma is to be distinguished from serum, which is plasma from which the fibrinogen has been separated in the process of clotting.

  • p. bound many electrolytes exist in plasma in a form in which they are bound to protein that reduces their lability and liability to loss in the urine, e.g., protein-bound iodine.
  • p. cell gingivitis–pharyngitis see feline lymphocytic-plasmacytic gingivitis–stomatitis.
  • p. cell myeloma see multiple myeloma.
  • p. clearing factor a lipoprotein lipase that lipolyzes the triglyceride in the chylomicrons of the plasma and hence clears it of cloudiness.
  • p. exchange the removal of plasma from withdrawn blood (plasmapheresis) and retransfusion of the formed elements and type-specific fresh-frozen plasma into the donor; done for removal of circulating antibodies or abnormal plasma components.
  • p. expanders see plasma volume expander.
  • fresh-frozen p. prepared from whole blood; a source of coagulation factors.
  • p. protein the heterologous group of proteins in circulating blood that includes albumin, lipoproteins, glycoproteins, transcortin, haptoglobin, ceruloplasmin, cholinesterase, α₂-macroglobulin, erythropoietin, transferrin, hemopexin, fibrinogen, plasminogen, and the immunoglobulins (γ-globulins).
  • p. substitute a fluid suitable for use as a replacement for plasma in the animal body. Usually a solution of gelatin or dextran.
  • therapeutic p. concentration a therapy–response relationship determined only by experiment; the plasma concentration that is matched by the desired therapeutic response.
  • p. turbidity test a qualitative test for fat absorption, performed by comparing the turbidity of plasma before and 2, 3, and 4 hours after the oral administration of fats, usually vegetable oil. Results are greatly influenced by delays in gastric emptying, so normally this test can only be relied upon to rule out malabsorption or maldigestion when evidence of absorption is found.
  • p. volume the estimation of plasma volume is essential to a complete knowledge of a patient’s fluid status. The common technique is by the intravenous injection of a known amount of a dye such as Evans blue and the subsequent measurement of the dilution that it has undergone in a set time period.

• plasmablast [plaz″m -blast′ik] the immature precursor of a plasmacyte, or plasma cell.

• plasmacyte, plasmocyte [plaz′m -sīt] see plasma cell.

• plasmacytic [plaz″m -sit′ik] of the nature of or pertaining to plasma cells.

  • p. stomatitis see feline lymphocytic-plasmacytic gingivitis–stomatitis.

• plasmacytic–lymphocytic see lymphocytic–plasmacytic.

• plasmacytoma [plaz″m -si-to′m] any focal neoplasm of plasmacytes, including those of multiple myeloma (plasma cell myeloma). Isolated plasmacytomas may occur outside the bone marrow (extramedullary plasmacytomas), affecting such tissues as the nasal, oral, pharyngeal and gastrointestinal mucosa, and the skin; called also plasma cell tumor. oral p. an unusual benign oral neoplasm of older dogs; appears as a red, lobulated, raised mass on the gingiva.

• plasmacytosis [plaz″m -si-to′sis] 1. an excess of plasma cells in the blood. 2. a synonym for Aleutian mink disease.

• plasmalemma [plaz″m -lem′] plasma membrane.

• plasmalogen [plaz-mal′ -j n] a member of one of three groups of glycerophospholipids found in lipid bilayer membranes, which is characterized by a vinyl ether linkage at the sn-1 position. Called also plasmenyl glycerophospholipid.

• plasmapheresis [plaz″m -f -re′sis] the removal of plasma from withdrawn blood, with retransfusion of the formed elements into the donor; generally, type-specific fresh frozen plasma or albumin is used to replace the withdrawn plasma. The procedure may be done for purposes of collecting plasma components or for therapeutic purposes. See also plasma exchange.

• plasmatic [plaz-mat′ik] pertaining to plasma; of the nature of plasma.

  • p. imbibition the process by which fluid from the recipient tissue bed provided nourishment for the donor tissue to maintain the viability of a skin graft in the initial 48–72 hours of grafting.

• plasmatorrhexis bursting of a cell from internal pressure.

• plasmic [plaz′mik] plasmatic; pertaining to or of the nature of plasma.

• plasmid [plaz′mid] an extrachromosomal self-replicating genetic element of a cell. In bacteria, plasmids are circular or sometimes linear DNA molecules that replicate independently from the chromosomes and are conserved through successive cell divisions. They can also be transmitted from one bacterium to another through conjugation; they include the F factor and R factor (resistance plasmid, contains antimicrobial resistance genes).

  • high copy number p. occurs in tens to several hundred copies per bacterium and are dependent solely on host enzymes for replication.
  • R factor p. see R factor.
  • relaxed p. a conformation in which the typical negative supercoiling of plasmid DNA has been enzymatically relaxed.

• plasmin [plaz′min] the active principle of the fibrinolytic or clot-lysing system, a proteolytic enzyme formed from plasminogen that hydrolyzes fibrin, fibrinogen, factor V, and other proteins. It has the particular ability to dissolve formed fibrin clots. Called also fibrinolysin.

  • p. inhibitors include α₂-macroglobulin, α₁-antitrypsin, C1-inactivator, antithrombin III.

• plasminogen [plaz-min′ -j n] the inactive precursor of plasmin, occur-ring in plasma and converted to plasmin by activators present in most tissues, blood, vessel walls, and body fluids; called also profibrinolysin.

  • p. activator inhibitor can protect the fibrin clot from premature lysis; called also PA inhibitor.
  • p. activator serine proteases that catalyze the activation of plasmin via proteolytic cleavage of plasminogen.

• plasmocyte [plaz′mo-sīt] plasmacyte.

• plasmocytoma [plaz″mo-si-to′m ] plasmacytoma.

• plasmodesma [plaz″mo-des′m ] pl. plasmodesmata a small, membranelined channel that connects the cytoplasm of adjacent plant cells and acts as an intercellular bridge to allow exchange of molecules between cells.

• plasmodicidal [plaz″mo-dľ-si′d l] destructive to plasmodia; malariacidal, antimalarial.

• Plasmodium [plaz-mo′de- m] a genus of apicomplexan protozoa in the family Plasmodiidae parasitic in the blood cells of animals and humans; malarial parasites. See also avian malaria.

  • P. berghei occurs naturally in tree rats; transmissible experimentally to other rodents.
  • P. brasilianum occurs in several monkey species, transmissible experimentally to humans and marmosets.
  • P. cathemerium occurs in passerine birds including sparrows, blackbirds.
  • P. chabaudi occurs in tree rats, transmissible to mice.
  • P. circumflexum parasitizes a wide range of birds including passerines and Canada goose.
  • P. coatneyi occurs in cynomolgus monkey; transmissible to other monkeys.
  • P. cynomolgi occurs in a wide range of monkeys; transmissible to humans causing tertian type malaria.
  • P. durae occurs in turkeys, transmissible to ducks.
  • P. elongatum transmissible experimentally to sparrows, canaries, and ducks.
  • P. eylesi found in gibbon monkeys.
  • P. falciparum, P. malariae, P. ovale, P. vivax the causes of the four specific types of human malaria. They are transmitted to the bloodstream of humans by the bite of anopheline mosquitoes. The sporozoites migrate and are transported via the blood streamto the liver, where they develop andmultiply within the parenchymal cells as merozoites, which then burst the liver cells and invade erythrocytes. Some of the merozoites develop into gametocytes, which are ingested by mosquitoes, beginning the sexual stage, which ends with the development of sporozoites.
  • P. fallax occurs in guinea fowl; transmissible to other birds.
  • P. gallinaceum occurs in fowls and transmissible to some other birds; many are resistant.
  • P. gonderi occurs in mandrills, mangabeys, rhesus monkeys.
  • P. griffithsi occurs in turkeys.
  • P. hexamerium found in passerine birds.
  • P. inui found in several species of monkeys.
  • P. juxtanucleare occurs in fowls; transmitted experimentally to turkeys.
  • P. knowlesi occurs in several species of monkeys and transmissible to humans in some countries.
  • P. lophurae occurs in pheasants; experimentally transmitted to chickens and ducklings.
  • P. reichenowi occurs in chimpanzee and gorilla.
  • P. relictum occurs in a variety of bird species.
  • P. rouxi found in sparrows and finches.
  • P. schwetzi occurs in chimpanzee and gorilla; transmissible experimentally to humans.
  • P. simium occurs in howler monkeys and humans.
  • P. vaughani found in many bird species.
  • P. vinckei occurs in a variety of rat species; transmissible to mice.

• plasmodium [plaz-mo′de- m] pl. plasmodia [Gr.] 1. an ampicomplexan protozoan parasite of the genus Plasmodium; including species that infect mammals, the causative agents of malaria, and birds. 2. a multinucleate continuous mass of protoplasm.

• plasmogen [plaz′mo-jen] the more vital or essential part of the cytoplasm; called also bioplasm.

• plasmolysis [plaz-mol′ľ-sis] contraction of cell protoplasm due to loss of water by osmosis.

• plasmoma [plaz-mo′m ] plasmacytoma.

• plasmon [plaz′mon] all of the cytoplasmic or extranuclear genetic material in an organism.

• plasmoschisis [plaz″mo-ske′sis] the splitting up of cell protoplasm.

• plasmotropism [plaz″mo-tro′piz- m] destruction of erythrocytes in the liver, spleen or marrow, as contrasted with their destruction in the circulation.

• plaster [plas′t r] 1. a mixture of materials that hardens; used for immobilizing or making impressions of body parts. 2. an adhesive substance spread on fabric or other suitable backing material, for application to the skin, often containing some medication, such as an anodyne or rubefacient.

  • p. cast see cast (5).
  • p. of Paris calcium sulfate dihydrate, reduced to a fine powder; the addition of water produces a porous mass used in making casts and bandages to support or immobilize body parts.
  • p. rolls the dry material for constructing plaster casts is packaged as rolls of impregnated gauze that is thoroughly soaked in water before being applied by unrolling around the site of the fracture.
  • p. shears special shears to cut plaster of Paris casts. Designed to cut upward away from the tissues to avoid injury. Called also plaster scissors, Esmarch plaster shears.
  • p. spreader a reverse pincer device with flat blades that are fitted down into a cut made in a plaster cast that is to be removed. Opening the handles forces the plaster apart.

• plastic [plas′tik] 1. tending to build up tissues to restore a lost part, as in reconstructive surgery. 2. capable of being molded. 3. a substance produced by chemical condensation or by polymerization.

  • p. dish dermatitis an inflammatory skin reaction on the muzzle of dogs caused by a hypersensitivity to plastic feeding dishes.
  • p. toy poisoning nervous signs including ataxia, hyperexcitability, and muscle twitching sometimes occur in cats after eating chidren’s plastic toys made of rubber and polythene.
  • p. vinyl sheeting a surgical drape made of synthetic material with the advantage of not being capillary and not abrasive to exposed tissue.

• plasticity [plas-tis′ľ-te] the quality of being plastic, or capable of being molded.

  • nervous system p. the ability of the nervous system to change its capabilities by experience; plays a major role in compensating for the loss of neurons with age and in recovery following neuronal damage.

• plasticizers [plas′tľ-si″z rs] mostly triaryl phosphates, such as tricresyl, triphenyl phosphates, which are poisonous. See also triorthocresyl phosphate.

• plastid [plas′tid] 1. double-membrane bound organelle of plant and algal cells, as well as some other eukaryotic organisms. They include photosynthetic organelles (e.g., chloroplast) and nonphotosynthetic organelles that are derived from them (e.g., remnant plastid of Apicomplexa). 2. plastination a process of preserving tissues, organs, and whole bodies in which water and fats are extracted and replaced with polymers. Used to prepare anatomical specimens for teaching and controversially in exhibits as works of art.

• plastron [plas′tron] skeletal and epidermal structure protecting the ventral surface of turtles and other chelonians.

• -plasty word element. [Gr.] formation, molding, shaping, plastic repair of.

• plate [plāt] 1. a flat structure or layer, as a flat layer of bone. 2. used as a fracture repair medium, including compression and locking plates. 3. to apply a culture medium to a glass plate. 4. to cultivate bacteria on such plates.

  • axial p. the primitive streak of the embryo.
  • basal p. primordial ventral horn of the spinal cord.
  • p. bender (2) a strong crimping device for manually bending a plate for a tricky bit of orthopedic repair.
  • buttress p. (2) a metal plate used in fracture repair to bridge and support a diaphyseal gap filled with a cancellous bone graft.
  • cloacal p. blind ending of the hindgut in the embryo.
  • cribriform p. a sieve-like partition between the cranial and nasal cavities. The posterior surface is divided by the vertical ethmoidal crest into two concave surfaces that contain the olfactory bulbs. It contains many small perforations through which the filaments of the olfactory nerves pass.

    P-56.

    

    Plastron of the tortoise

    P-57.

    

    Metacarpalphalangeal radiograph demonstrating trandphyseal bridging with a ’plate and screw’ technique

  • deck p. see roof plate (below).
  • dorsal p. see roof plate (below).
  • equatorial p. the collection of chromosomes at the equator of the spindle in mitosis.
  • floor p. the unpaired ventral longitudinal zone of the neural tube; called also ventral plate.
  • foot p. the flat portion of the stapes.
  • growth p. the epiphyseal cartilage at which new bone formation occurs to lengthen long bones during their growth phase. Called also physis. See also epiphyseal plate.
  • medullary p. neural plate.
  • muscle p. myotome (2).
  • nasal p. region of modified skin around the nostrils in the embryonic carnivore or small ruminant.
  • nasolabial p. region of modified skin around the nostrils in the embryo of cattle.
  • neural p. a thickened band of ectoderm in the midbody region of the developing embryo, which develops into the neural tube; called also medullary plate.
  • neutralization p. (2) a bone plate placed to protect against the forces acting on the fracture site.
  • oral p. separates the stomodeum from the pharyngeal cavity; subsequently breaks down to become the palatoglossal arch; called also oropharyngeal membrane.
  • orthopedic bone p. (2) a metal plate screwed to the two fragments of a fractured bone to provide fixation and permit healing in correct alignment.
  • roof p. the unpaired dorsal longitudinal zone of the neural tube; called also dorsal plate and deck plate.
  • rostral p. region of modified skin around the nostrils in the porcine embryo.
  • sole p. a mass of protoplasm in which a motor nerve ending is embedded.
  • spinal p. metal or plastic plates may be used to stabilize thoracolumbar or lumbar spinal fractures. With one plate on each side of a row of dorsal spinal processes, they are bolted together in the spaces between processes.
  • tarsal p. one of the plates of connective tissue forming the framework of either (upper or lower) eyelid.
  • tectorial p. the roof of the ethmoidal labyrinth of the internal ear.
  • tension band p. (2) a bone plate placed on the tension side of a fracture that counteracts tensile forces, converting them into compression forces at the fracture site.
  • ventral p. floor plate.

• platelet [plāt′l t] a small disc or plate-like structure, the smallest of the formed elements in blood. Blood platelets (called also thrombocytes) are disk-shaped, nonnucleated blood elements with a very fragile membrane; they tend to adhere to uneven or damaged surfaces. They average about 250,000 per cubic millimeter of blood and are formed in the red bone marrow by fragmentation of megakaryocytes, the largest of the bone marrow cells. Platelet production is controlled by a hormone, thrombopoietin, and regulatory lymphocytes acting at the stem cell level. At any given time, about one-third of the total blood platelets can be found in the spleen; the remaining two-thirds are in the circulating blood. The functions of platelets are related to the clotting of blood. Because of their adhesion and aggregation capabilities, platelets can occlude small breaks in blood vessels and prevent the escape of blood. Platelets that have adhered to exposed collagen in damaged vessels release ADP in milliseconds, which in turn initiates the synthesis of thromboxane A₂, a very potent prostaglandin that causes platelet aggregation and localized vasoconstriction. Fibrinogen, factors V and VIII, calcium ions, platelet phospholipid (PF-3), associated with the platelet membrane are also released. Substances contained within the platelet granules such as thromboglobulin, heparin neutralizing activity (PF-4) mitogens such as platelet derived growth factor, thrombospondin, ADP, serotonin, and calcium ions are also released by aggregated platelets.

  • p.-activating factor (PAF) see platelet-activating factor.
  • p. adhesion the adherence of platelets to exposed subendothelium; the first step in component of hemostasis.
  • p. aggregation the progressive accumulation of platelets, attracted by other platelets once adhesion begins. Thromboxane A₂ causes irreversible platelet aggregation.
  • p. aggregation test a known platelet aggregating factor such as collagen, ADP or thrombin is added to a suspension of the platelets under test and the degree of aggregation measured by decrease in turbidity of the suspension.
  • p. count platelet numbers are assessed by counting the platelets in a counting chamber, a hematology analyzer, or by estimating the number on a stained blood smear and reported as cells/μl. Counts less than 10,000–50,000 are likely to be associated with spontaneous hemorrhage. See also thrombocytopenia.
  • p.-derived growth factor one of three growth factors released by platelets that undergo the release reaction; the growth factors stimulate endothelial cell proliferation.
  • p. distribution width (PDW) an indication of variation in platelet size (anisocytosis), which can be a sign of active platelet release.
  • p. factor 3 (PF-3) test, p. release test test the antiplatelet activity of serum; used to detect circulating antiplatelet antibodies. Antibody–antigen reactions involving platelets cause the release of PF-3 from platelets which in turn shortens the contact-activated clotting time of platelet-rich plasma (PRP).
  • p. factors factors important in hemostasis that are contained in or attached to the platelets: platelet factor 1 is adsorbed clotting factor V from the plasma; platelet factor 2 is an accelerator of the thrombin–fibrinogen reaction; platelet factor 3 is a phospholipid with potent procoagulant activity; platelet factor 4 is capable of inhibiting the activity of heparin (heparin neutralizing activity).
  • mean p. volume (MPV) the average size of circulating platelets, reported as fL (μm³). Greater size is an indication of increased megakaryocyte shedding of platelets.
  • p. plug formation see platelet aggregation (above).
  • p. release reaction measured by the degree of secondary ADP-mediated aggregation that occurs. This is assessed by the amount of PF-4, PF-3 or serotonin, etc., released.
  • p. retention tested by testing the adhesiveness of a suspension of the subject platelets to a glass bead column or standard size filter.
  • p. rich plasma plasma prepared by centrifugation to separate out red blood cells but not platelets for transfusion.
  • p. storage-pool disease inherited autosomal thrombopathias characterized by deficiency of platelet storage granules; includes Chediak-Higashi syndrome of Persian cats, cyclic hematopoiesis of gray collies, and ADP deficiency in a family of American cocker spaniels.
  • p. transfusion transfusion of fresh, nonchilled whole blood is the usual method of transfusing platelets to an animal with thrombocytopenia.

• platelet-rich plasma therapy a form of regenerative medicine in which preparations of concentrated autologous plasma, providing platelets and growth factors, is injected into the area of tissue injury. These act to enhance access of healthy inflammatory cells, the formation of new blood vessels and connective tissue, and regeneration of skin. Used particularly in musculoskeletal and tendon injuries in horses and osteoarthritis in dogs. Often shortened to PrP.

• plateletpheresis [plāt″l t-f -re′sis] thrombocytapheresis. Removal of platelets from a collected blood sample and return of the remaining blood components to the donor.

• platform scales [plat′form] a weighing machine that has a platform on which animals can stand to be weighed.

• plating [plāt′ing] 1. the process of using a plate as in orthopedic surgery. 2. in bacteriology, the process of inoculating bacteria onto agar media for cultivation.

  • bone p. a method of fracture stabilization in which one or more metal plates are applied across the fracture and anchored, usually by screws, in the fragments.
  • replication p. the transfer of cells from bacterial colonies on one plate to another plate, with a colony growing in the same position as in the original plate.

• platinum (Pt) [plat′ľ-n m] a chemical element, atomic number 78, atomic weight 195.09.

  • p. chemotherapy see platinum complexes (below).
  • p. complexes inhibit DNA synthesis and have some alkylating activity. They are used in cancer chemotherapy, but they can have marked side effects of nausea, vomiting, nephrotoxicity, and bone marrow suppression. See also cisplatin, carboplatin.

• platy- word element. [Gr.] broad, flat.

• platybasia [plat″ľ-ba′se- ] malformation of the base of the skull, with forward displacement of the upper cervical vertebrae and bony impingement on the brainstem. It is accompanied by neurological signs referable to the medulla oblongata, cervical spinal cord, and cranial nerves. Called also basilar impression.

• Platycobboldia loxodontis a stomach bot of the African elephant. The fly lays eggs around the nostrils and the larvae migrate to the stomach through the tissues.

• platycoelous [plat″ľ-se′l s] having one surface flat and the other concave, referring to vertebrae.

• platyfishes popular and colorful aquarium fish (Xiphophorus spp.) They give birth to live young. Includes the common platy (X. maculatus) and many variations.

• platyhelminth [plat″ľ-hel′minth] a member of the phylum Platyhelminthes; the flatworms. Includes cestodes and trematodes, the tapeworms, and the flukes.

• platyhieric [plat″e-hi-er′ik] having a wide sacrum.

• Platymyarian an arrangement of the longitudinal somatic muscles of nematodes in which the contractile part is wide and shallow and lies close to the epidermis.

• platynosomiasis [plat″ľ-no-so-mī′ -sis] infection with trematodes in the genus Platynosomum.

• Platynosomum [plat″ľ-no-so′mum] a genus of digenetic trematodes in the family Dicrocoeliidae.

  • P. ariestis a nonpathogenic fluke found in the intestine of sheep.
  • P. fastosum occurs in the liver and bile ducts of domestic cats in tropical and subtropical regions; causes a mild to severe disease, called lizard poisoning, characterized by vomiting, diarrhea, and jaundice. Cats become infested by eating infected lizards. Called also P. concinnum.

• platyonychia increased curvature of the claws in the long axis.

• platypellic, platypelloid [plat″ľ-pel′ik] having a broad pelvis.

• platypus pl. platypuses a semiaquatic, carnivorous monotreme (Ornithorhynchus anatinus), found only in Australia. It resembles a beaver, covered with fine red-brown to gray fur, with a broad, dorsally flattened tail, webbed and clawed feet, and a broad flat, duck-like beak. Adult males have a prominent tarsal spur, which is used defensively and can emit a venom. This semiaquatic animal lives in a burrow with an underwater entrance. Like the echidnas, the only other members of the order Monotremata, it lays eggs, hatches them, and feeds the young from milk that is discharged through the skin in a skinfold. Called also duck-billed platypus. pl. Platypuses or Platypus

• platyrrhine [plat′ľ-rīn] 1. having a broad nose. 2. member of the parvorder Platyrrhini of primates.

• platys short name for platyfishes.

• platysma [pl -tiz′m] the superficial sheet of cutaneous muscle over the face and neck.

• Play-Doh a child’s modeling medium useful in obliterating air spaces in superficial sites, e.g., clefts in the sole of the normal horse hoof, to improve the quality of the resultant image.

• PLE protein losing enteropathy.

• pledget [plej′ t] a small compress or tuft, usually of cotton, used to apply disinfectant or medicament to the skin.

• -plegia word element. [Gr.] paralysis.

• pleiotropism, pleiotropy [pli-ot′r -piz- m] the production by a single gene of two or more seemingly unrelated phenotypic effects.

• Pleistophora [plīs-tof′ -r] a genus of microsporidian parasites, mostly of fish.

  • P. anguillarum occurs in the muscles of eels and causes body deformities when muscles atrophy.
  • P. cepedianae produces large cysts that protrude from the body wall of affected fish.
  • P. hyphessobryconis found in the skeletal muscles of aquarium fish causing ‘neon fish disease’. The muscles are patchily transparent, and the fish lose their balance, and the fins degenerate.
  • P. macrozoarcidis causes the development of cysts and tumors in the muscles of marine fish.
  • P. ovariae infects the ovaries of minnows causing infertility.
  • P. salmonae infects the gills of trout causing clubbing and fusion.

• pleocytosis [ple″o-si-to′sis] the presence of a greater than normal number of cells in cerebrospinal fluid.

• pleomastia [ple″o-mas′te- ] the presence of supernumerary mammary glands or nipples; polymastia.

• pleomorphism [ple″o-mor′fiz- m] having more than one shape or form.

• pleonasm [ple′o-naz- m] an excess of parts; see polymeria.

• pleonectic [ple″o-nek′tik] characterized by having a higher than normal O₂ content at a given Po₂; said of blood.

• pleonosteosis [ple″on-os″te-o′sis] abnormally increased ossification.

• plerocercoid [ple″ro-sur′koid] the second larval stage of a bothriocephalidean or diphyllobothriidean (=pseudophyllidean) cestode that follows the procercoid. This larva infects a wide range of vertebrate hosts including fish, amphibia, reptiles, mammals, birds. They are elongated, have a solid body, and carry an adult scolex. As a migrating larva of a tapeworm, this is an infectious stage of importance in predation; the definitive host becomes infected by eating the tissues of the second intermediate host.

• Plesiomonas [ple″se-o-mo′n s] facultatively anaerobic gram-negative rods which are mainly found in fish and reptiles. The only species is P. shigelloides.

• plesiotherapy [ple″se-o-ther′ -pe] a form of very superficial radiotherapy; ⁹⁰Sr probes are used. Called also surface brachytherapy.

• plessesthesia [ples″es-the′zh ] use of percussion as a diagnostic aid.

• platycoria [plat″ľ-kor′e- ] a dilated condition of the pupil of the eye.

• plessimeter [ples-im′ -t r] pleximeter.

• plessor [ples′or] plexor.

• PLET agar a selective medium containing polymyxin, lysozyme, EDTA, and thallous acetate used for isolation of Bacillis anthracis from samples likely to be contaminated with other bacteria.

• plethora [pleth′ -r] a general term denoting an overabundance, or specifically, an excessive amount of blood.

• plethysmograph [plě-thiz′mo-graf] any device for measuring and recording variations in the volume of an organ, part or limb.

  • body p. a device used in pulmonary function tests to measure parameters such as functional residual capacity (FRC) and lung–thorax compliance (C_LT). It consists of a large box in which the subject can be sealed so that volume of the thorax can be determined from pressure changes in the box while the lung volume and gas pressure in the lungs are measured by spirometry.

• plethysmography [plě″thiz-mog′r -fe] the determination of changes in volume by means of a plethysmograph.

  P-58.

  

  Lateral radiograph of a cat with pleural effusion due to pyothorax. The fluid obscures the cardiac silhouette and cranial margin of the diaphragm

• pleura [ploor′ ] pl. pleurae [Gr.] the serous membrane investing the lungs (pulmonary pleura) and lining the walls of the thoracic cavity (parietal pleura), the two layers enclosing a potential space, the pleural cavity.

• pleuracotomy [ploor″ -kot′ -me] incision into the pleural cavity.

• pleural [ploor′ l] emanating from or pertaining to the pleura.

  • p. effusion accumulation of fluid in the space between the membrane encasing the lung and that lining the thoracic cavity. The normal pleural space contains only a small amount of fluid to prevent friction as the lung expands and deflates. If, however, there is a disturbance in either the production of this fluid or its removal, the fluid accumulates and threatens collapse of the lung. In extreme cases there is total collapse of the lung and mediastinal shift.
  • p. friction rub the abrasive sound made by the rubbing together of two acutely inflamed serous surfaces, as in acute pleurisy. Later separation of the surfaces by accumulated exudate marks the disappearance of the rub. The sound is synchronous with the respiratory movements.
  • p. gas may be produced by gas-forming bacteria or be caused by leakage from thoracentesis or lesions of the airways.
  • p. hemorrhage see hemothorax.
  • p. infection see pyothorax.
  • p. inflammation see pleuritis.
  • p. paracentesis see thoracentesis.
  • p. peel heavy fibrinous deposits on the pleura.
  • p. stripping 1. removal of the pleura at an abattoir when the tissue is discolored or superficially diseased, and the remainder of the carcass is suitable for human consumption. 2. surgical removal of excessive pleural fibrin deposits via thoracotomy.

• pleurapophysis [ploor″ -pof′ľ-sis] a rib, or a vertebral process corresponding to a rib.

• pleurectomy [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-rek′t -me] excision of a portion of the pleura.

• pleuritic [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -rit′ik] pertaining to or emanating from pleurisy. See also pleural.

  • p. ridge thoracic immobility with the chest expanded combined with abdominal respiration causes the costochondral arches to be more visible than usual. Called pleuritic ridge because of its occurrence in pleurisy as a response to pain on chest movement.
  • p. thrill palpable counterpart of the pleural friction rub.

• pleuritis, pleurisy [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -ri′tis ploor′ľ-se] inflammation of the pleura; it can be caused by infection, injury, or tumor. It can be a sequela of lung diseases, particularly of pneumonia or lung abscess. Typical signs of acute pleurisy include painful respiratory movements causing grunting and rapid shallow breathing. Chronic pleurisy includes empyema with collapse of lung and dyspnea with toxemia, or interference with respiratory movements by adhesions.

  • bile p. inflammation of the pleura resulting from perforating thoracic trauma with hepatodiaphragmatic fistula or iatrogenically from percutaneous liver biopsy techniques.
  • constrictive p. adhesions between the parietal and visceral pleura restrict movement of the lungs and the chest wall.
  • dry p. inflammation of the pleura without effusion. Painful, the cause of dry cough, shallow, rapid respiration, and sounds of friction rubbing. Can be a stage in the development or healing of serous or purulent pleuritis.
  • restrictive p. development of fibrous tissue on pleura may restrict expansion of lungs.

• pleur(o)- word element. [Gr.] pleura, rib, side.

• pleurocele [ploor′o-sēl] hernia of lung tissue or of pleura.

• pleurocentesis [ploor″o-sen-te′sis] thoracentesis; paracentesis of the pleural cavity.

• pleuroclysis [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-rok′l -sis] injection of fluids into the pleural cavity.

• pleurodesis [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-rod′ -sis] the production of adhesions between the visceral and parietal pleurae. May be produced intentionally by the instillation of irritating drugs into the pleural cavity or by abrading the visceral and parietal pleural surfaces to achieve adhesions. Called also pleural symphysis, pleural sclerosis.

  P-59.

  

  Fibrinous pleuritis in a horse at necropsy

• pleurodont [ploor′o-dont] teeth with no roots or alveoli that are ankylosed to the jaw bones; seen in snakes and lizards.

• pleurodynia [ploor″o-din′e- ] paroxysmal pain in the intercostal muscles due to muscular disease or irritation of the pleural surface.

• pleurogenic, pleurogenous [ploor″o-jen′ik] originating in the pleura.

• pleurography [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-rog′r -fe] radiography or computed tomography (CT) of the pleural cavity by coating the parietal and visceral pleura with a contrast agent.

• pleurohepatitis [ploor″o-hep″ -ti′tis] hepatitis with inflammation of a portion of the pleura near the liver.

• pleurolith [ploor′o-lith] a concretion in the pleura.

• pleurolysis [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -rol′ľ-sis] surgical separation of the pleura from its attachments.

• pleuromutilins a class of antimicrobials that inhibit bacterial protein synthesis; includes tiamulin and valnemulin; used to treat respiratory infections in pigs and poultry, and they are important in the treatment of swine dysentery.

• pleuroparietopexy [ploor″o-p -ri′ -to-pek″se] the operation of fixing the visceral pleura to the parietal pleura, thus binding the lung to the chest wall.

• pleuropericardial [ploor″o-per″ľ-kahr′de- l] pertaining to the pleura and pericardium.

  • p. celom, p. coelom that part of the original body cavity in the fetus that subsequently divides into the pericardial and pleural cavities.
  • p. fold the beginnings of the pleuropericardial septum in the developing embryo.
  • p. septum the septum produced by the fusion of the two pleuropericardial folds; it divides the original pleuropericardial coelom into the pleural and pericardial coeloms, later the cavities of the same names.

• pleuropericarditis [ploor″o-per″ľ-kahr-di′tis] inflammation involving the pleura and the pericardium.

• pleuroperitoneal [ploor″o-per″ľ-to-ne′ l] pertaining to the pleura and peritoneum.

  • p. canal an embryonic, transient canal venting pleural and peritoneal cavities.
  • p. hernia herniation of abdominal viscera through a pleuroperitoneal hiatus defect.
  • p. hiatus defect faulty closure of the pleuroperitoneal canals by the embryonic diaphragm.
  • p. membrane folds of tissue that extend into the peritoneal cavity of the developing embryo and participate in the separation of the pleural and peritoneal cavities.

• pleuropneumonia [ploor″o-n $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-mo′ne-] pneumonia accompanied by pleurisy.

  • contagious bovine p. see contagious bovine pleuropneumonia.
  • contagious caprine p. see contagious caprine/ovine pleuropneumonia.

• porcine p. a highly contagious disease of growing pigs caused by Actinobacillus (Haemophilus) pleuropneumoniae (parahaemolyticus) with several serotypes with differing geographical distribution and virulence. Characterized by severe dyspnea, and a short course, and high mortality rates. A flood-stained frothy discharge from the nose and mouth is characteristic. Disease follows a stressor such as transport or movement to another pen or building.

• pleuropneumonia-like organisms (PPLO) a term applied to the mycoplasmas because of their similarity to Mycoplasma mycoides subspecies mycoides, the cause of contagious bovine pleuropneumonia in cattle.

• pleuroscopy [ploor-os′k -pe] visual examination of the pleural cavity and its contents via a rigid, or flexible, endoscope introduced through an incision in the chest wall.

• pleurothotonos [ploor″o-thot′ -n s] tetanic bending of the body to one side.

• pleurothotonus [ploor″o-thot′ -n s] pleurothotonos.

• pleurotomy [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-rot′ -me] incision of the pleura.

• pleurovisceral [ploor″o-vis′ r- l] pertaining to the pleura and viscera.

• plexiform [plek′sľ-form] resembling a plexus or network.

• pleximeter [plek-sim′ -t r] a plate to be struck in mediate percussion; preferably with a percussion hammer.

• plexitis [plek-si′tis] inflammation of a nerve plexus.

• plexogenic [plek′so-jen″ik] giving rise to a plexus or plexiform growth.

  • p. pulmonary arteriopathy pulmonary vascular lesions caused by pulmonary hypertension and hyperfusion in congenital cardiac defects such as patent ductus arteriosus.

• plexopathy [plek-sop′ -the] any disorder of a plexus, especially of nerves.

  • lumbar p. neuropathy of the lumbar plexus.

• plexor [plek′sor] a hammer used in diagnostic percussion; plessor. See also pleximeter.

• plexus [plek′s s] pl. plexus, plexuses [L.] a network or tangle, chiefly of veins or nerves.

  • brachial p. see brachial plexus.
  • cardiac p. the plexus around the base of the heart, chiefly in the epicardium, formed by cardiac branches from the vagus nerves and the sympathetic trunks and ganglia, and made up of sympathetic, parasympathetic, and visceral afferent fibers that innervate the heart.
  • capsular p. terminal branches of the renal interlobular arteries that continue to the surface and terminate beneath the capsule of the kidney in the form of a plexus.
  • carotid p’s nerve plexuses surrounding the common, external, and internal carotid arteries.
  • celiac p. a plexus of autonomic fibers and sympathetic nerve ganglia that surround the origin of the celiac artery, and supply the abdominal viscera.
  • celiacomesenteric p. a plexus of autonomic nerve fibers and sympathetic ganglia around the origin of the celiac and cranial mesenteric arteries; called also solar plexus.
  • cervical p. a network of nerve fibers formed by the first four cervical nerves and supplying the structures in the region of the neck.
  • choroid p. infoldings of blood vessels of the pia mater covered by a thin coat of ependymal cells that form tufted projections into the third, fourth, and lateral ventricles of the brain; they secrete the cerebrospinal fluid.
  • coccygeal p. a nerve plexus formed by the ventral branches of the coccygeal and last sacral nerves.
  • coronary p. a venous plexus within the coronet of the hoof.
  • cutaneous p’s superficial, middle, and deep, inter-communicating plexuses of blood vessels are identified as supplying blood to haired skin.
  • cystic p. a nerve plexus near the gallbladder.
  • dental p. either of two plexuses (inferior and superior) of nerve fibers, one from the inferior alveolar nerve, situated around the roots of the lower teeth, and the other from the superior alveolar nerve, situated around the roots of the upper teeth.
  • gonadal p. the collection of parasympathetic and sympathetic nerves to the gonads.
  • hoof p. plexus of veins draining the hoof region in the horse.
  • lumbar p. see lumbar plexus.
  • lumbosacral p. see lumbosacral plexus.
  • mesenteric p. parasympathetic and sympathetic nerve supply to the abdominal organs.
  • myenteric p. see Auerbach plexus.
  • nerve p. a plexus composed of intermingled nerve fibers.

• pampiniform p. 1. a plexus of veins from the testis and the epididymis, constituting part of the spermatic cord. 2. a plexus of ovarian veins in the broad ligament of the uterus.

  • p. papilloma see plexus papilloma.

• parametrial p. the venous plexus within the broad ligament providing venous drainage to the uterus and vagina.

• pulmonary p. the array of autonomic nerves that supply the lungs.

  • renal p. autonomic nerve supply to the kidney.
  • sacral p. a plexus arising from the ventral branches of the last few lumbar and first few sacral spinal nerves.
  • solar p. see celiacomesenteric plexus (above).
  • subpapillary p. a superficial plexus, one of three, of blood vessels in haired skin.
  • tympanic p. a network of nerve fibers supplying the mucous lining of the tympanum and auditory tube.

• PLH pharyngeal lymphoid hyperplasia.

• PLI pancreatic lipase immunoreactivity.

• plica [pli′k ] pl. plicae [L.] a ridge or fold.

  • p. abomasi permanent folds in the abomasal mucosa.
  • p. circulares permanent folds in the mucosa of the small intestine.
  • p. glossoepiglottica a median fold in the pharyngeal mucosa that passes from the root of the tongue to the base of the epiglottis.
  • pterygomandibular p. passes from the lower jaw to the upper behind the last molar teeth on both sides of the mouth.
  • p. rumenoreticularis the fold that partly separates the rumen from the reticulum.
  • p. semilunaris conjunctivae the fold of conjunctiva that encloses the substance of the third eyelid.
  • p. venae cavae the pleural fold that extends from the mediastinum to the caudal vena cava.

• plicamycin an antineoplastic antibiotic produced by Streptomyces argillaceus and S. tanashiensis; particularly effective in treating the hypercalcemia associated with canine lymphosarcoma. Called also mithramycin.

• plicate [pli′kāt] plaited or folded.

• plication [pli-ka′sh n] the operation of taking tucks in a structure to shorten it.

  • bowel p. suturing of one bowel segment to another; done to prevent recurrence of intussusception.

• plicotomy [pli-kot′ -me] surgical incision of the posterior fold of the tympanic membrane.

• Pliohippus the last three-toed horse in the evolution of Equidae; existed during the Pliocene era. The lateral toes were small and finally disappeared in this stage. The connecting link from the primitive horse to the modern day Equus.

• plombage [plom-bahzh′] [Fr.] the filling of a space or cavity in the body with inert material; once a treatment for tuberculosis in humans.

• Plott a medium-sized (40–60 lb), sturdy scent hound with large, pendulous ears. The distinctive black and brindle coat is short, and the tail is long and tapered. Developed in the US, the breed is used in packs for hunting bear, wild boar, wolves, and mountain lions, traditionally in the Great Smoky Mountains. Called also Plott hound. Mucopolysaccharidosis I, an inherited metabolic storage disease, occurs in the breed. The official state dog of North Carolina.

• plow harness a harness that consists of a collar and hames, a backstrap, and chains that run from the hames through the back strap to the swinglebar of the plow.

• plowshare bone see pygostyle, vomer.

• PLP pyridoxal phosphate.

• PLR pupillary light reflex.

• PLTpsittacosis-lymphogranuloma venereum-trachoma (group); the Chlamydiales.

• pluck 1. an abattoir term for the thoracic viscera plus the liver, after separation from the esophagus and the diaphragm. Includes the larynx, trachea, lungs, heart, and liver, plus the spleen in sheep. 2. removal of the feathers from birds during the preparation of the carcass for meat. Scalding for 2 minutes in water plus detergent at 134°F is a great aid. 3. removal of wool from the carcass of a sheep dead long enough for the wool to become loose.

• plucking box restraint box used for feather harvesting of ostriches.

• plug [plug] an obstructing mass.

  • epithelial p. mass of ectodermal cells that temporarily closes the external naris of the fetus.
  • mucous p. a plug formed by secretions of mucous glands, of the cervix uteri and closing the cervical canal during pregnancy.

• plum Prunusdomestica.

  • yellow plum see Ximenia americana.

• plum pudding dog see Dalmatian.

• ‘plum pudding’ liver see telangiectasia.

• plumage the feather coat of a bird for one molt.

  • nuptial p. the brightly colored feathers that are present on drakes and many male birds prior to and during the breeding season; this plumage is replaced during the eclipse molt.

• plumbic [plum′bik] pertaining to lead.

• plumbism [plum′biz- m] see lead¹ poisoning.

• plumbum (Pb) [L.] lead.

• plumping absorption of fluid of the egg in the hen’s oviduct before investing it with the shell.

• pluri- word element. [L.] several or more.

• pluriglandular pertaining to several glands or their secretions.

• plurigravida [ploor″ľ-grav′ľ-d ] multigravida; a female pregnant for the third (or more) time.

• plurilocular [ploor″ľ-lok′u-l r] multilocular; having many cells or compartments.

• pluripara [ploo-rip′ -r] multipara; a female that has had two or more pregnancies that resulted in viable offspring.

• pluriparity [ploor″ľ-par′ľ-te] multiparity; the condition of being a pluripara (multipara).

• pluripotent [pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-rip′-t nt] (a cell with) the potential to differentiate into any cell type of the three embryonic germ cell layers (i.e., endoderm, mesoderm, ectoderm).

  • p. stem cell. see stem cell.

• pluripotential [ploor″ľ-po-ten′shal] characterized by pluripotentiality; the potential of giving rise to several different cell types.

• pluripotentiality [ploor″ľ-po-ten″she-al′ľ-te] having the ability to develop in any one of several different ways, or to affect more than one organ or tissue.

• pluronic detergent [plur-on′ik] used as an oral prophylactic against bloat in ruminants; overdosing can have toxic effects.

• plus sense in RNAviruses, the genomic RNA is of the same polarity 3′ to 5′ as messenger RNA so that after adsorption, penetration, uncoating, and release of the viral RNA into the cytoplasm of the cell the viral RNA acts immediately as a messenger RNA for the synthesis of viral proteins, some of which are essential for the replication of the virus.

• plutonium (Pu) [ploo-to′ne- m] a chemical element, atomic number 94, atomic weight 242.

• Plymouth Rock a black-and-white barred-colored fowl, with distinctive crossbands of black and white across the feathers, giving the bird a spangled look. A heavyweight meat bird with a single comb.

• Pm chemical symbol, promethium.

• PM abbreviation for post mortem.

• pm picometer.

• PMI point of maximal intensity.

• PMN polymorphonuclear neutrophil.

• PMO Pasteurized Milk Ordinance.

• PMS pregnant mare serum.

• PMSG pregnant mare serum gonadotropin. Now equine chorionic gonadotropin (eCG).

• PMSY pigs marketed per sow per year. A major determinant of profitability in farrow-to-finish swine units. 20 is a minimal target.

• PMWS postweaning multisystemic wasting syndrome.

• PN parenteral nutrition.

• -pnea word element. [Gr.] respiration, breathing.

• pne(o)- word element. [Gr.] relationship to breath, breathing.

• pneogram spirogram.

• pneograph spirograph.

• pneometer spirometer.

• pneoscope pneograph.

• pneumarthrograph [noo″mahr′thro-graf] a radiograph obtained by pneumarthrography.

• pneumarthrography [noo″mahr-throg′r -fe] radiography of a joint after it has been injected with a gas as a contrast medium; called also pneumoarthrography.

• pneumarthrosis [noo″mahr-thro′sis] gas or air in a joint.

• pneumatic [noo-mat′ik] pertaining to air or respiration.

• pneumatization [noo″m -tľ-za′sh n] the formation of air cavities in tissue, especially such formation in the temporal bone.

• pneumat(o)- word element. [Gr.] related to air, gas or respiration.

• pneumatocele [noo-mat′o-sēl] 1. hernia of lung tissue. 2. a usually benign, thin-walled, air-containing cyst of the lung. 3. a tumor or sac containing gas, especially a gaseous swelling of the scrotum.

• pneumatogram [noo-mat′o-gram] spirogram.

• pneumatograph [noo-mat′o-graf″] spirograph.

• pneumatometer [noo″m -tom′-t r] spirometer.

• pneumatometry [noo″m -tom′ -tre] measurement of the air inspired and expired.

• pneumatonograph [noo″m -to′mo-graf] a pneumatic applanation tonometer or tonographer that measures intraocular pressure via a gassuspended plunger.

• pneumatorrhachis [noo″m -to-rak′is] the presence of gas in the vertebral canal.

• pneumatosis [noo″m -to′sis] air or gas in an abnormal location in the body.

  • p. coli gas or air dissecting the tissues in the wall of the large intestine.
  • p. cystoides intestinalis a condition characterized by the presence of thin-walled, gas-containing cysts in the wall of the intestines in humans, a condition similar to intestinal emphysema in pigs.

• pneumaturia [noo″m -tu′re-] gas or air in the urine.

• pneumectomy [noo-mek′t -me] pneumonectomy.

• pneum(o)- word element. [Gr.] related to air, gas, lung, or respiration.

• pneumoacupuncture acupuncture in which air is injected into the subcutaneous space to stimulate an acupuncture point; used to treat muscle atrophy.

• pneumoangiography [noo″mo-an″je-og′r -fe] contrast radiography of the blood vessels of the lungs.

• pneumoarthrography [noo″mo-ahr-throg′r -fe] pneumarthrography

• pneumobilia [noo″mo-bil′e- ] gas in the biliary tree.

• pneumocephalus [noo″mo-sef′ -l s] air in the intracranial cavity.

• pneumococcus [noo″mo-kok′ s] see Streptococcus pneumoniae.

• pneumocolon [noo″mo-ko′l n] air in the colon; it may be placed there as an aid to endoscopic or radiological diagnosis.

• pneumocolonography [noo″mo-ko″l n-og′r -fe] radiography of the colon after air or gas has been introduced to aid in contrast.

• pneumoconiosis [noo″mo-ko″ne-o′sis] any of a group of lung diseases resulting from inhalation of particles of industrial substances, such as the dust of iron ore or coal, and permanent deposition of substantial amounts of such particles in the lungs. The disease is rare in animals unless there is an unusual exposure to a dusty environment. Silicosis in horses is a form. Exercise intolerance and chronic cough are the cardinal signs.

• Pneumocystis [noo″mo-sis′tis] opportunistic fungal pathogens that cause severe pneumonia in immunocompromised hosts, now considered as part of an early-diverging lineage of Ascomycetes.

  • P. carinii the causative agent of interstitial plasma cell pneumonia in humans and immunocompromised dogs and Arabian foals.

• pneumocystogram [noo″mo-sis′to-gram] an image obtained by pneumocystography.

• pneumocystography [noo″mo-sis-tog′r -fe] radiography of the urinary bladder after injection of air or gas.

• pneumocystosis [noo″mo-sis-to′sis] 1. pneumonia characterized by interstitial accumulation of plasma cells. 2. pneumonia caused by Pneumocystis carinii infection; usually latent or subclinical except in immunocompromised humans, dogs, cats, pigs, horses, goats, primates, rabbits.

• pneumocyte [noo-mo-sīt′] includes granular and alveolar pneumocytes; see alveolar² cell.

• pneumoderma [noo″mo-dur′m ] subcutaneous emphysema; air or gas in subcutaneous tissues.

• pneumodynamics [noo″mo-di-nam′iks] the dynamics of the respiratory process.

• pneumoencephalitis [noo″mo- n-sef″ -li′tis] see Newcastle disease.

• pneumoencephalogram [noo″mo- n-sef′ -lo-gram] the radiograph produced by pneumoencephalography. Replaced by magnetic resonance imaging (MRI).

• pneumoencephalography [noo″mo- n-sef″-log′r -fe] radiographic visualization of the fluid-containing structures of the brain after cerebrospinal fluid is withdrawn and replaced by air, oxygen, or helium. Replaced by magnetic resonance imaging (MRI).

• pneumoenteritis [noo″mo-en″t r-i′tis] inflammation of the lungs and intestine as in stomatitis pneumoenteritis. See peste des petits ruminants.

• pneumoextraperitoneography [noo″mo-eks″tr -per′ľ-to-ne-o-og′r -fe] infiltration of the subperitoneal tissues with nitrogen or carbon dioxide to give a better visualization of the kidney.

• pneumogastric nerve [noo″mo-gas′trik] vagus nerve. See Table 13.

• pneumogastrogram [noo″mo-gas′tro-gram] radiograph of an air-filled stomach, used to screen for gastric foreign bodies and assessment of stomach position, size, and shape. Not useful for defining details of the mucosa.

• pneumogastrography [noo″mo-gas-trog′r -fe] a radiographic technique which utilizes a gas-filled stomach to visualize the organ. See also gastrography.

• pneumography 1. imaging of the respiratory movements. 2. radiography of a part after injection of a gas.

• pneumohemopericardium [noo″mo-he″mo-per″ľ-kahr′de- m] air or gas and blood in the pericardium.

• pneumohemothorax [noo″mo-he″mo-thor′aks] gas or air and blood in the pleural cavity.

• pneumohyd rometra [noo″mo-hi″dro-me′tr ] gas and fluid in the uterus.

• pneumohydropericardium [noo″mo-hi″dro-per″ľ-kahr′de- m] air or gas with fluid in the pericardium.

• pneumohydrothorax [noo″mo-hi″dro-thor′aks] air or gas with fluid in the thoracic cavity.

• pneumolith [noo′mo-lith] a pulmonary concretion.

• pneumolithiasis [noo″mo-lľ-thi′ -sis] the presence of concretions in the lungs.

• pneumolobectomy [noo″mo-lo-bek′t -me] excision of lung tissue, usually of a single lobe (lobectomy).

• pneumomediastinum [noo″mo-me″de- s-ti′n m] the presence of air or gas in tissues of the mediastinum, occurring as part of a disease or introduced intentionally.

• pneumometer [noo″mom′ -t r] spirometer.

• pneumometra physometra; air or gas in the uterus; occurs in mares with incompetent perineum and vestibulovaginal junction.

• pneumomycosis [noo″mo-mi-ko′sis] any fungal disease of the lungs.

• pneumomyelography [noo″mo-mi″ -log′r -fe] a generally unused technique of radiography of the spinal canal after withdrawal of cerebrospinal fluid and injection of air or gas.

• pneumonectomy [noo″mo-nek′t -me] excision of lung tissue, of an entire lung (total pneumonectomy) or less (partial pneumonectomy), or of a single lobe (lobectomy).

• pneumonia [noo-mo′ne- ] inflammation of the parenchyma of the lung. It is often accompanied by inflammation of the airways and sometimes of the adjoining pleura. Clinically it is manifested by an increase in the rate and depth of respiration at all degrees of severity up to dyspnea. There is also moist cough, and abnormality of the breath sounds on auscultation. In bacterial pneumonia, there is usually a severe toxaemia; in viral pneumonia, it is usually minor. See also bronchopneumonia, pleuropneumonia.

  • Arabian foal p. an inexorably progressive pneumonia of certain Arabian foals born with primary severe combined immunodeficiency in which adenovirus plays a dominant role but is complicated by other microorganisms, particularly Pneumocystis carinii.
  • aspiration p. see aspiration pneumonia.
  • atypical p. histologically the pneumonia is atypical in that there are no signs of acute inflammation, and it is characterized by an exudation of eosinophilic, protein-rich fluid in the alveoli that may become organized to form a hyaline membrane. In animals that survive for several days there is epithelialization of the alveolar walls. In humans there is a primary atypical pneumonia caused by Mycoplasma pneumoniae. In animals, the best known example is atypical interstitial pneumonia of cattle.
  • bronchointerstitial p. the lesions are centered on the bronchioles, and a prominent feature is the accumulation of lymphocytes in interstitial tissue; typical of pneumonias caused by aerogenous virus infections, especially myxoviruses.
  • brooder p. see brooder pneumonia.
  • chronic undifferentiated p. of sheep see enzootic pneumonia.
  • corynebacterial p. see Rhodococcus equi pneumonia.
  • cuffing p. chronic undifferentiated pneumonia of sheep in which lymphofollicular sheaths around the bronchioles are a feature.
  • equine cryptococcal p. see epizootic lymphangitis.
  • desquamative p. a chronic pneumonia associated with Mycoplasma spp. and characterized by organization of the exudate within bronchioles and bronchi, and proliferation of the interstitial tissue and epithelium.
  • desquamative interstitial p. chronic pneumonia with desquamation of large alveolar cells and thickening of the walls of distal air passages; marked by dyspnea and nonproductive cough.
  • embolic p. results from hematogenous spread from an intravascular lesion elsewhere in the body. The best known example is caudal vena caval thrombosis.
  • endogenous-lipid p. focal alveolar accumulations of foamy, lipid-filled macrophages that may impede alveolar clearance. Usually an incidental postmortem finding in laboratory rodents, fur-bearing animals, and uncommonly cats and dogs.
  • enzootic p. see enzootic pneumonia.
  • fibrinous p. an acute fulminating pneumonia, often lobar in distribution, characterized by a fibrinous exudate. Fibrinous describes the exudate, not the anatomical distribution so that the term fibrinous pneumonia should not be used interchangeably with lobar pneumonia.
  • foreign body p. see aspiration pneumonia.
  • gangrenous p. usually an sequela of aspiration pneumonia.
  • giant-cell p. a secondary lesion in dermatosis vegetans in pigs; lesions marked by the presence of a proliferative giant-cell type of diffuse interstitial pneumonia.
  • granulomatous p. has a slow course characterized by granulomatous, not exudative, inflammation. Sporadic cases occur in immunodeficient animals. It is a characteristic of tuberculosis and systemic fungal infections, e.g., coccidioidomycosis.
  • hypostatic p. caused by pooling of blood and some decrease in viability of the dependent lung in an old, sick, or debilitated animal that is in lateral recumbency for a long period. The infection is secondary to hypostasis.
  • inhalation p. see aspiration pneumonia.
  • interstitial p. pneumonia in which there is diffuse or patchy damage to alveolar septa widely distributed through the lung lobes. There is an early intra-alveolar exudative phase followed by significant proliferation and enlargement of the alveolar epithelial cells and a thickening of the interstitial tissue. Most interstitial pneumonias in animals are infectious including viral, bacterial, fungal, and protozoal causes, but may be caused by chemical injury, acute pancreatitis, or shock, as in acute respiratory distress syndrome.
  • lipid p. a specific type of aspiration pneumonia caused by the inhalation of oil droplets; most commonly associated with the forced administration of paraffin oil or cod-liver oil to cats. Called also medication pneumonia, lipoid pneumonia. See also aspiration pneumonia.
  • lobar p. a fulminating bronchopneumonia in which entire pulmonary lobes are diffusively inflamed and then consolidated. Pneumonic pasteurellosis in cattle is the type disease. The animal is critically ill with anoxia and toxemia.

    P-60.

    

    Pneumonyssoides (Pneumonyssus) caninum.

    P-61.

    

    Pneumopericardiogram in a dog

  • lobular p. an oldfashioned term for bronchopneumonia.
  • lymphoid interstitial p. see maedi.
  • ovine progressive p. see maedi.
  • parasitic p. see lungworm disease.
  • rhodococcal p. of foals see Rhodococcus equi pneumonia.
  • stable p. see equine influenza.
  • suppurative p. of foals see Rhodococcus equi pneumonia.

• pneumonic [noo-mon′ik] pertaining to the lung or to pneumonia.

• pneumonitis [noo″mo-ni′tis] inflammation of lung tissue. See also pneumonia.

  • feline p. infection by Chlamydia felis causes a chronic, often recurrent, conjunctivitis and infrequently lower respiratory disease. See also feline viral respiratory disease complex.
  • eosinophilic p. most often associated with occult heartworm infection in dogs, where microfilariae trapped in the pulmonary circulation provoke an eosinophilic inflammatory response and chronic cough.
  • hypersensitivity p. a local type III hypersensitivity reaction resulting from inhalation of antigens, seen in cattle fed moldy hay and the group of diseases in humans that includes farmer’s lung and bird-fancier’s lung.
  • chemical p. results from aspiration of gastric acids.
  • uremic p. occurs in dogs with terminal uremia; acute lung injury causes pulmonary edema and respiratory distress.

• pneumon(o)- word element. [Gr.] related to the lung.

• pneumonocentesis [noo-mo″no-sen-te′sis] surgical puncture of a lung for aspiration.

• pneumonocyte [noo-mon′o-sīt] collective term for the alveolar epithelial cells (great alveolar cells and squamous alveolar cells) and alveolar phagocytes of the lungs.

• pneumonolysis [noo″mo-nol′ľ-sis] division of tissues attaching the lung to the wall of the chest cavity, to permit collapse of the lung.

• pneumonomycosis [noo-mo″no-mi-ko′sis] pneumomycosis.

• pneumonopathy [noo″mo-nop′ -the] any lung disease.

• pneumonopexy [noo-mo′no-pek″se] fixation of the lung to the thoracic wall.

• pneumonorrhaphy [noo″mo-nor′ -fe] suture of the lung.

• pneumonosis [noo″mo-no′sis] any lung disease.

• pneumonotomy [noo″mo-not′ -me] incision of the lung.

• Pneumonyssoides [noo″mo-nis-oi′dēz] syn. Pneumonyssus; a genus of mites in the family Dermanyssidae.

  • P. caninum found in the nasal passages and sinuses of dogs causing irritation manifested by sneezing, and rubbing of the nose.

• Pneumonyssus [noo″mo-nis′ s] a genus of mites in the family Dermanyssidae.

  • P. caninum see Pneumonyssoides caninum.
  • P. simicola found in the bronchi of the rhesus monkey where it may cause irritation with sneezing and coughing.
  • P. stammeri a mite found in the lungs of New World primates.

• pneumopericardiography [noo″mo-per″e-kahr″de-og′r -fe] injection of air or carbon dioxide into the pericardial sac, usually after a comparable amount of fluid has been withdrawn.

• pneumopericardium [noo″mo-per″ľ-kahr′de- m] the presence of air or gas in the pericardial cavity.

• pneumoperitoneography [noo″mo-per″ľ-to″ne-og′r -fe] a radiograph taken of the abdomen after the intraperitoneal infusion of air or carbon dioxide to give better contrast.

• pneumoperitoneoscopy [noo″mo-per″ľ-to″ne-os′k -pe] a procedure in which air is infused into the peritoneal cavity in order to improve the view obtained through a laparoscope.

• pneumoperitoneum [noo″mo-per″ľ-to-ne′ m] the presence of air or gas in the peritoneal cavity, occurring as part of a disease or introduced intentionally.

• pneumoperitonitis [noo″mo-per″ľ-to-ni′tis] peritonitis with accumulation of air or gas in the peritoneal cavity.

• pneumopleuritis [noo″mo-pl $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -ri′tis] inflammation of the lungs and pleura.

  P-62.

  

  Lateral radiograph of a cat with pneumoperitoneum secondary to gastric perforation

  P-63.

  

  Lateral radiograph of a dog with pneumothorax after being hit by a car

• pneumopyopericardium [noo″mo-pi″o-per″ľ-kahr′de- m] air or gas and pus in the pericardium.

• pneumopyothorax [noo″mo-pi″o-thor′aks] air or gas and pus in the pleural cavity.

• pneumoradiography [noo″mo-ra″de-og′r -fe] radiography of a part after injection of air or other gas as contrast material.

• pneumoretroperitoneum [noo″mo-ret″ro-per″ľ-to-ne′ m] the presence of air or gas in the retroperitoneal space.

• pneumorrhagia [noo″mo-ra′j ] hemorrhage from the lungs; severe hemoptysis.

• Pneumospirura a genus of spiruroid nematodes in the family Pneumospiruridae.

  • P. bassarisci found in the bronchioles of the ringtail.
  • P. capsulata found in the common badger.
  • P. rodentium found in the lungs of gerbils and birds.
  • P. ratti found in the Norway rat.

• Pneumostrongylus a genus of nematodes in the family Protostrongylidae. Parasites of the lungs of wild ruminants.

• pneumotachograph [noo″mo-tak′o-graf] an instrument for recording the velocity of respired air.

• pneumotachography [noo″mo-tak-og′ra-fe] the science of using a pneumotachograph.

• pneumotachometer [noo″mo-t -kom′-t r] a transducer for measuring expired air flow.

• pneumotaxic [noo″mo-tak′sik] regulating the respiratory rate.

  • p. center one of the four respiratory centers; located in the upper, rostral part of the pons; rhythmically inhibits inspiration.

• pneumotherapy [noo″mo-ther′ -pe] treatment of disease of the lungs.

• pneumothorax [noo″mo-thor′aks] entry of air into the pleural cavity in sufficient quantity to cause collapse of the lung and consequent decreased ventilation of the lung. If it is unilateral, there is a mediastinal shift with displacement of the heart to the other side of the chest. Breath sounds are absent from the affected side.

  • closed p. air leaks from a discontinuity in the lung into the pleural cavity.
  • iatrogenic p. may occur following intrathoracic surgery or in association with procedures that involve entry into the pleural cavity, such as thoracentesis or placement of a chest drain.
  • open p. caused by an open wound in the chest wall.
  • pseudo p. artifactual increased radiolucency of the thorax resembling free air in the pleural cavity. Also known as false pneumothorax.
  • spontaneous p. due to an unknown cause.
  • tension p. a particularly dangerous form of pneumothorax that occurs when air escapes into the pleural cavity from a bronchus but cannot regain entry into the bronchus. As a result, continuously increasing air pressure in the pleural cavity causes progressive collapse of the lung tissue. If not relieved, it can lead to lung collapse and mediastinal shift.

• pneumotomy [noo-mot′ -me] pneumonotomy.

• pneumotoscopy [noo″mo-tos′k -pe] a means of assessing compliance of the tympanic membrane and determining whether there is fluid in the middle ear. The tympanic membrane is visualized through an otoscope, watching for movement when air is moved in and out of the external ear canal using a pneumatic bulb attached to the otoscope.

• pneumouterus [noo″mo-u′t r- s] see pneumometra, physometra.

• pneumovagina [noo″mo-v -ji′n] involuntary aspiration of air into the vagina so that the vagina is chronically distended. Usually incompatible with fertility. See also rectovaginal fistula.

• pneumoventriculogram [noo″mo-ven-trik′u-lo-gram] the radiograph produced by the use of ventriculography (1).

• pneumoventriculography [noo″mo-v n-trik″u-log′r -fe] pneumoencephalography.

• Pneumovirinae [noo″mo-vir-i′ne] a subfamily of viruses in the family Paramyxoviridae. See Pneumovirus.

• Pneumovirus [noo′mo-vi″r s] a genus in the subfamily Paramyxovirinae that includes respiratory syncytial virus of humans, cattle, sheep, goats, dogs, and cats.

• -pnoea see -pnea.

• PNS peripheral nervous system.

• PO, p.o. [L.] per os (by mouth; orally).

• Po chemical symbol, polonium.

• Poa [po′ ] genus of grasses in family Poaceae. Contains many very productive fodder grasses including the bluegrasses.

  • P. aquatica Glyceriamaxima.
  • P. hueca South American grass; contains an indole alkaloid that causes incoordination and convulsions.
  • P. pratensis Kentucky bluegrass, a popular pasture grass.

• poach damage caused to sodden pasture by the hooves of cattle and sheep. In clay soils and when the ground is sufficiently wet the damage caused by a heavy stocking rate of sheep may be very high. Said also of the take-off in front of a jump in an equitation course or a race. Called also pugging.

• poaching 1. illegal, secret trapping or killing of game. 2. excessive traffic by animals, especially ungulates, on wet pasture fields causing rupture of pasture mat and loss of grass and clover carrying capacity.

• pock, pockmark [pok] specifically, a depressed scar typically left by the cutaneous lesions of poxviruses in humans, but used generically to describe lesions of similar appearance in any species, of any cause, and whether on the skin or other surfaces.

• pocket pet [pok′ t] a general term, used to describe very small animals kept as pets; usually includes hamsters, guinea pigs, gerbils, rats, and mice.

• pod a small herd or school of cetaceans, such as whales, dolphins, or porpoises.

• podarthritis [pod″ahr-thri′tis] inflammation of the joints of the feet.

• poddy 1. the act of artificial rearing. 2. an animal being reared in this way, e.g., a poddy calf.

• poddying technique for artificial rearing of young, e.g., on a bottle, with an eyedropper, from a bucket. See also artificial rearing.

• podencephalus [pod″ n-sef′-l s] a fetus without a cranium, the brain hanging by a pedicle.

• podium pl. podia [L.] a foot-like process, such as an extension of the protoplasm of a cell.

• pod(o)- word element. [Gr.] relationship to the foot.

• podocyte [pod′o-sīt] an epithelial cell of the visceral layer of a renal glomerulus, having a number of footlike radiating processes (pedicles).

• pododemodicosis [po″do-dem″ -dľ-ko′sis] pododermatitis caused by Demodex spp. See also demodicosis.

• pododerm [pod′o-d rm] the specially adapted part of the skin that provides nourishment to the hooves or claws. See also corium.

  P-64.

  

  Pododemodecosis

  P-65.

  

  Plasma cell pododermatitis. The central footpad is swollen with a doughy texture when palpated. Mild hyperkeratosis is also present

• pododermatitis [po″do-dur″m -ti′tis] term used to describe inflammation of a paw (dog or cat), hoof (ruminant or horse), or feet, talons, webbing birds). Most common use is with reference to cattle where it is used synonymously with footrot, but also used increasingly to describe dermatitis or pyoderma of the feet in dogs. In poultry associated with high litter pH and high litter moisture. See also interdigital pyoderma.

  • p. circumscripta bruising and necrosis of the sole in the angle between the bar and the wall of the hoof in horses. See also corn (2).
  • demodectic p. see pododemodicosis.
  • plasma cell p. a nonpainful swelling, sometimes with ulceration and exuberant granulation tissue, on the footpads of cats. The cause is unknown but believed to be immunological.
  • suppurative p. underrun sole with pus formation.
  • ulcerative p. a disease of rabbits, guinea pigs, and other caged small mammals, caused by pressure from a cage floor on the backs of the metatarsal bones; it may progress to arthritis. Wet conditions and restricted movement also contribute. Staphylococcus aureus is most commonly recovered. Called also sore hocks in rabbits, and bumblefoot in guinea pigs.

• pododynamometer [pod″o-di″n -mom′-t r] a device for determining the strength of the leg muscles.

• podophyllin [pod″o-fil′in] the pharmacologically active resin extracted from podophyllum.

• podophyllotoxin [pod″o-fil′o-tok″sin] main active constituent of podophyllin resin, which has been used for its caustic properties as a topical treatment for warts; etoposide and teniposide are less toxic derivatives with antineoplastic activities.

• podophyllum [pod″o-fil′ m] the dried rhizome and roots of Podophyllum peltatum.

  • p. resin a mixture of resins from podophyllum, used as a topical caustic in the treatment of certain papillomas. Was used at one time as a purgative but was capable of causing fatal superpurgation.

• podoplasty [pod″o-plas′te] plastic repair of the paw

  • fusion p. surgery of the paw that excises interdigital skin between digital and metacarpal or metatarsal pads and sutures pads together. A radical treatment for severe pododermatitis.
  • separation p. complete surgical removal of interdigital skin as a treatment for interdigital cysts.

• podotrochlear apparatus [pod″o-trok′le- r] the navicular bone, navi-cular bursa, navicular suspensory ligament, distal sesamoidean impar ligament, deep digital flexor tendon, and the distal digital annular ligament.

• podotrochleitis [po″do-trok-le-ī′tis] see navicular disease.

• podotrochlosis [po″do-trok-lo′sis] podotrochlitis.

• Poecilia [pe-sil′e- ] a genus of brackish water fish that bear live offspring; known generally as mollies. Includes guppies.

• pogonion [po-go′ne-on] the craniometric point located at the anterior midpoint of the chin.

• -poiesis word element. [Gr.] formation.

• poikil(o)- word element. [Gr.] irregular, variable, mottled.

• poikiloblast [poi′kľ-lo-blast″] an abnormally shaped erythroblast.

• poikilocyte [poi′kľ-lo-sīt″] an abnormally shaped erythrocyte; includes acanthocyte, codocyte, dacryocyte, eccentrocyte, echinocyte, elliptocyte, keratocyte, leptocyte, ovalocyte, pyknocyte, schizocyte, spherocyte, stomatocyte.

• poikilocytosis [poi″kľ-lo-si-to′sis] the presence of poikilocytes in the blood.

• poikiloderma [poi″kľ-lo-dur′m ] a condition characterized by pigmentary and atrophic changes in the skin, giving it a mottled appearance.

• poikilospherocyte [poi″kľ-lo-sfēr′o-sīt] small spheroidal erythrocytes caused by fragmentation.

• poikilotherm [poi-kil′o-therm″] an animal that exhibits poikilothermy; a cold-blooded animal.

• poikilothermic [poi-kil′o-therm″ik] characterized by poikilothermy.

• poikilothermism [poi″kľ-lo-thur′miz- m] the state induced by poikilothermy.

• poikilothermy [poi″kľ-lo-thur′me] the physiological state of having body temperature that varies with that of the environment.

• poinsettia see Euphorbia pulcherrima.

• point [point] 1. a small area or spot; the sharp end of an object. 2. to approach the surface, like the pus of an abscess, at a definite spot or place. 3. a single tine of an antler. 4. extremities of a sheep fleece that has been removed from the sheep and laid out on a classing table. 5. in acupuncture, specific locations usually along meridians where needles or other methods of treatment are applied. Called also acupoints.

  • auricular p. the craniometric point marked by the center of the opening of the external acoustic meatus.
  • boiling p. the temperature at which a liquid will boil: at sea level, 212°F (100°C).
  • dew p. the temperature at which moisture in the atmosphere is deposited as dew.
  • electrical p. finding identification of acupuncture points by the use of an electrical point finder; this measures the resistance of the skin to the flow of electricity; it is much lower over acupuncture points.
  • freezing p. the temperature at which a liquid begins to freeze; for water, 32°F (0°C).
  • ice p. the temperature of equilibrium between ice and air-saturated water under one atmosphere pressure.
  • isobestic p. the wavelength at which two substances have the same absorptivity.
  • isoelectric p. (pI) the pH of a solution in which molecules of a specific substance, such as a protein, have equal numbers of positively and negatively charged groups and therefore do not migrate in an electric field lacrimal p. lacrimal puncta.
  • p. of lay the age of sexual maturity in female fowls.
  • p. of maximal impulse (PMI) the point on the chest where the impulse of the left ventricle is felt most strongly. It is usually on the left chest wall, around the area of the fifth costochondral junction.
  • melting p. the minimum temperature at which a solid begins to liquefy.
  • nodal p’s two points on the axis of an optical system situated so that a ray falling on one will produce a parallel ray emerging through the other.
  • p. outbreak see point epidemic.
  • paper p. very fine, tapered swabs used in endodontics to dry up the root canal.
  • p. prescriptions details of the exact needle procedures and locations of insertions for the treatment of specific diseases.
  • p. selection can be based on a table of prescriptions for specific diseases, or on the basis of which acupoints are tender, or on the basis of the innervation of the area of the lesion, and so on for a series of 11, and possibly more, strategies.
  • special action p’s. acupoints used only to influence specific organs or tissues.
  • trigger p. a spot on the body at which pressure or other stimulus gives rise to specific sensations or clinical signs.
  • triple p. the temperature and pressure at which the solid, liquid, and gas phases of a substance are in equilibrium.

• point finder an electronic device used to detect the exact location of points in acupuncture, based on variations in electrical impedance of the skin.

• Pointer [point′ r] a medium to large (55–65 lb), lean gun dog with long neck, pendulous ears, and long pointed tail. The coat is short and fine in solid color or white with lemon, black, liver, or orange patches or ticks. Called also English pointer to distinguish it from several other breeds with pointer in their name. See also pointing (2).

  • Hungarian p. see Vizsla.
  • Italian p. see Spinoni Italiani.

• pointer [point′ r] an injury such as a contusion or avulsion of muscle attachments at a bony prominence.

• pointillage [Fr.] massage with the points of the fingers.

• pointing 1. the posture adopted by a horse with one lame limb, lame with a weight-bearing lameness. The toe of the affected limb is rested on the ground in front of its normal position, and less weight is taken on it than normal. 2. the posture adopted by a pointer-type hunting dog when it detects the presence of a bird—looking straight at the location of the bird, perfectly still with the tail straight out behind and one front limb flexed with the carpus at right angles. 3. the coming to a head or maturation of an abscess.

• point-of-care test various clinicopathologic testing procedures which may be carried out in the veterinary hospital or clinic, rather than sending the samples out to a distant commercial laboratory. Called also cage-side test.

• points 1. specific parts of the conformation. 2. restricted areas of color. In dogs this refers to contrasting coloring over the eyes, on the face, legs, and feet. In cats it is the face, ears, feet, and tail and is used to describe the pigmentation pattern seen in Siamese, e.g., seal-point, blue-point, tabby-point, etc.

  • p. of the horse a list of the outstanding anatomical landmarks of the animal that are used as guiding points when judging the quality of the animal’s conformation. This is used mostly in show judging. The list is usually expressed in lay terms such as muzzle, pastern, hock.

• Poiretia punctata causes neurological disease in sheep and cattle in Brazil, appears caused by an unidentified toxin.

• poise [poiz, pwahz] the unit of viscosity of a liquid; the number of grams per centimeter per second. Centipoise, 0.01 poise, is the standard unit used.

• Poiseuille’s law, Poiseuille’s equation [pwah-swēz′] the law that expresses the relationship between the rate of flow of a liquid in a tube and the pressure gradient in the tube, the radius of the tube, the length of the tube, and the viscosity of the liquid.

• poison [poi′z n] a substance that, on ingestion, inhalation, absorption, application, injection, or development within the body may cause structural damage or functional disturbance. Called also a toxicant. Corrosives are poisons that destroy tissues directly. They include the mineral acids, such as nitric acid, sulfuric acid, and hydrochloric acid, and the caustic alkalis, such as ammonia, sodium hydroxide (lye), sodium carbonate, and sodium hypochlorite; and carbolic acid (phenol). Irritants are poisons that inflame the mucous membranes by direct action. These include copper sulfate, salts of lead, cantharidin, oxalate raphides, and many plant and insect poisons. Nerve poisonss act on the nerves or affect some of the basic cell processes. This large group includes the narcotics, such as opium, heroin, and cocaine, and the barbiturates, anesthetics, and alcohols. Blood poisons act on the blood and deprive it of oxygen. They include carbon monoxide, carbon dioxide, nitrite, and the gases used in chemical warfare. Some blood poisons destroy the blood cells or the platelets. See also poisoning and names of individual poisons.

  • berry p. Gastrolobiumparvifolium.
  • box p. Gastrolobiumparviflorum.
  • bullock p. Gastrolobiumtrilobum.
  • p. bush Thesiumnamaquense.
  • p. bride bush Pavettaschumanniana.
  • bushman’s p. Acokanthera spp.
  • camel p. Erythrophleumchlorostachys.
  • candyup p. Stypandra glauca.
  • Champion Bay p. Gastrolobiumoxyloboides.
  • clover-leaf p. Goodialotifolia.
  • cluster p. Gastrolobiumbennettsianum.
  • crinkle-leaf p. Gastrolobiumvillosum.
  • desert p. bush Gastrolobiumgrandiflorum.
  • Gilbernene p. Gastrolobiumrotundifolium.
  • granite p. Gastrolobiumgraniticum.
  • heart-leaf p. bush Gastrolobiumbilobum or G. grandiflorum.
  • Hill River p. Gastrolobiumpolystachyum.
  • hook-point p. Gastrolobiumhamulosum.
  • horned p. Gastrolobiumpolystachyum.
  • Hutt River p. Gastrolobiumpropinquum.
  • insect p. see bee sting, epicauta vittata, tick paralysis.
  • p. ivy Toxicodendronradicans.
  • kite-leaf p. Gastrolobiumlaytonii.
  • lamb p. Isotropiscuneifolia.
  • p. leaf Dichapetalumcymosum.
  • mallet p. Gastrolobiumdensifolium.
  • marlock p. Gastrolobiumparviflorum.
  • narrow-leaf p. Gastrolobiumstenophyllum.
  • net-leaf p. Gastrolobiumracemosum.
  • pea-blossom p. Isotropis spp.
  • prickly p. Gastrolobiumspinosum.
  • rigid-leaf p. Gastrolobiumrigidum.
  • river p. Gastrolobiumforrestii.
  • river p. tree Excoecariadallachyana.
  • rock p. Gastrolobiumcallistachys.
  • Roe’s p. Gastrolobiumspectabile.
  • round-leaf p. Gastrolobiumpycnostachyum.
  • runner p. Gastrolobiumovalifolium.
  • sandplain p. Gastrolobiummicrocarpum.
  • scale-leaf p. Gastrolobiumappressum.
  • p. sedge Schoenusasperocarpus.
  • slender p. Gastrolobiumheterophyllum.
  • slender lamb p. Isotropisjuncea.
  • spike p. Gastrolobiumglaucum.
  • Stirling Range p. Gastrolobiumvelutinum.
  • p. suckleya Suckleya suckleyana.
  • thick-leaf p. Gastrolobiumcrassifolium.
  • wallflower p. Gastrolobiumgrandiflorum.
  • p. walnut Cryptocarya pleurosperma.
  • wodjil p. Gastrolobiumfloribundum.
  • woolly p. Gastrolobiumtomentosum.
  • York Road p. Gastrolobiumcalycinum.

• Poison Control Center public facility set up to provide information around the clock to provide information on toxicity of substances and current information of correct first aid methods and antidotes for poisoning emergencies. See Animal Poison Control Center.

• poisoning [poi′z n-ing] the morbid condition produced by a poison. The poison may be swallowed, inhaled (as in carbon monoxide poisoning), injected by a stinging insect as in a bee sting, or spilled or otherwise brought into contact with the skin.

  • blood p. septicemia.
  • food p. a group of acute illnesses due to ingestion of contaminated food. See also food poisoning.poisoning by foods that are perfectly suitable for human consumption but that can be toxic to dogs and cats. These include grapes, raisins, currants, sultanas; onion, garlic, leek, and chives, chocolate, macadamia nuts, unbaked bread dough, xylitol, alcohol.
  • malicious p. laying a bait to poison an animal without the owner’s consent.

• poisonous [poi′z n- s] having the properties of a poison.

  • p. plants plants that contain specific chemical poisons, although they may not have been identified. They are a different group from plants that cause illness if eaten in very large amounts or have physical qualities that cause illness, e.g., clover in bloat, tree loppings in omasal impaction, thorns, or spines. There is a third group of plants, those that are only intermittently poisonous. These form a very large group known to have caused nitrite, cyanide, or oxalate poisoning but are valuable plants and are safe if used appropriately. See also under the names of individual plants or the toxins that they contain.
  • p. animals animals that secrete or contain a substance that is toxic when ingested by another animal. Examples include the monarch butterfly, poisonous dart frogs, Japanese blowfish.

• Poisson distribution [pwah-saw′] a statistical distribution that often describes the sampling frequency of individual, isolated counts in time and space.

• Poitou ass a French, longhaired, black or dark brown donkey.

• pokeroot [pōk′root] Phytolacca americana.

• pokeweed [pōk′wēd] Phytolacca americana.

  • p. mitogen (PWM) see pokeweed mitogen.

• pol gene a gene found in the retroviral genome that encodes reverse transcriptase.

• Poland China a large black pig with white points; produced in the USA.

• polar [po′l r] 1. emanating from or pertaining to a pole. 2. being at opposite ends of a spectrum of values.

  P-66.

  

  Poitou ass

• polarimeter [po″l -rim′-t r] a device for measuring the rotation of plane polarized light.

• polarimetry [po″l -rim′ -tre] measurement and interpretation of the rotation of the plane polarized light.

• polarine a glycoalkaloid found in plants of the family Solanaceae and thought to contribute to poisoning by them.

• polariscope [po-lar′ľ-skōp] an instrument used to measure polarized light.

• polarity [po-lar′ľ-te] the condition of having poles or of exhibiting opposite effects at the two extremities.

  • cell p. a feature of epithelial cells which defines an apical surface facing the outside which is separated by a tight junction from the basolateral surface.

• polarization [po″l r-ľ-za′sh n] the action or process of affecting radiation and especially light so that the wave travels in one direction

• polarizer [po′l r-īz″ r] an appliance for polarizing light.

• polarography [po″l r-og′r -fe] an electrochemical technique for identifying and estimating the concentration of reducible elements in an electrochemical cell by means of the dual measurement of the current flowing through the cell and the electrical potential at which each element is reduced.

• pole [pōl] 1. either extremity of any axis, as of a body organ. 2. either one of two points that have opposite physical qualities (electric or other).

  • control p. a pole with a loop at one end for capturing wild or dangerous small animals. The loop is put over the animal’s head and pulled tight. Good poles have a nonslip device so that the animal cannot slip free because of relaxation on the cord by the operator.
  • frontal p. the most prominent part of the anterior end of each hemisphere of the brain.
  • occipital p. the posterior end of the occipital lobe of the brain.
  • temporal p. the prominent anterior end of the temporal lobe of the human brain.

• poleaxe a long-handled hammer, about 9–10 lb, originally with an axe blade at the front, used at one time for stunning cattle prior to bleeding out at slaughter.

• polecat (Mustela putorius), or European polecat, a member of the Mustelidae family of Carnivora, it has a long body, short legs, and short furry tail; the coat is dark brown with a dark raccoon-like mask. Native to Eurasia and northern Africa, it can eject a foul-smelling material from its anal (musk) glands when attacked. Called also fitch, black, or forest polecat. Domestication has resulted in the domestic ferret.

• poley 1. a polled animal; one without horns. 2. knee pad on an Australian stock saddle.

• poliglecaprone 25 a monofilament synthetic absorbable suture material characterized by low tissue reactivity and high tensile strength.

• poli(o)- [po′le-o] word element. [Gr.] relationship to gray matter.

• polioclastic [po″le-o-klas′tik] destroying the gray matter of the nervous system.

• poliodystrophia [po″le-o-dis-tro′fe- ] poliodystrophy.

• poliodystrophy [po″le-o-dis′tr -fe] atrophy of the cerebral gray matter.

• polioencephalitis [po″le-o- n-sef″ -li′tis] inflammation of the gray matter of the brain.

• polioencephalomalacia [po″le-o-en-sef″ -lo-m-la′sh] softening of the cerebrocortical gray matter distributed in a laminar pattern. Called also laminar cortical necrosis, cortical necrosis.

• periventricular p. degenerative changes in periventricular nuclei in carnivores in thiamine deficiency. See thiamine nutritional deficiency.

  • ruminant p. a sporadic disease, occurring in cattle and sheep, that has several different causes, including the ingestion of excess amount of sulfates in feed and water, thiamine inadequacy caused by ingestion of preformed thiaminases in certain plants or production of thiaminase by ruminal microbes. Characterized by a sudden onset of blindness, head-pressing, nystagmus, opisthotonos, and clonic-tonic convulsions and death in 24–48 hours. Mild cases may remain standing, walk aimlessly, and head press. At autopsy, there is cerebral edema and laminar necrosis of the gray matter of the brain. Called also cerebrocortical necrosis. May also be seen in some cases of acute lead poisoning in cattle.
  • sulfur-associated p. diets with more than 0.4% sulfur can induce polioencephalomalacia in cattle; forage content of the diet will influence this threshold; major sulfur sources include elemental sulfur, molasses, sulfates in drinking water, plants in the family Brassicaceae, manure gas (hydrogen sulfide). Called also ‘blind staggers’ and previously attributed erroneously to selenium poisoning.

• polioencephalomeningomyelitis [po″le-o- n-sef″-lo-m-ning″go-mi″ -li′tis] inflammation of the gray matter of the brain and spinal cord and of the meninges.

• polioencephalomyelitis [po″le-o-en-sef″ -lo-mi″ -li′tis] inflammation of the gray matter of the brain and spinal cord.

  • feline p. a slowly progressive disease of unknown etiology in cats, including large Felidae; clinical signs include ataxia, paresis, and hyperesthesia.

• polioencephalomyelopathy a degeneration of gray matter of the brain and spinal cord.

  • hereditary p. an autosomal recessive disorder in Australian cattle dogs. Starting at a young age, there are psychomotor seizures, weakness, and thoracic limb stiffness progressing to spastic tetraparesis.

• polioencephalopathy [po″le-o- n-sef″-lop′ -the] any disease of the gray matter of the brain.

• poliomalacia [po″le-o-m -la′sh] softening of the gray matter of the central nervous system.

  • focal symmetrical spinal p. a disease of young sheep and of unknown etiology observed only in Kenya and characterized by focal softening of the gray matter of the spinal cord, especially the cervical cord, and paralysis especially of the forelimbs. Similar lesions and clinical signs are also observed in pigs, except that the paralysis is posterior. It is associated with selenium toxicosis.

• poliomyelitis [po″le-o-mi″ -li′tis] inflammation of the gray matter of the spinal cord; also the name applied to the viral disease of humans and also known as polio.

  • feline p. see feline polioencephalomyelitis.
  • p. suum see porcine viral encephalomyelitis.

• poliomyelopathy [po″le-o-mi″ -lop′ -the] any disease of the gray matter of the spinal cord.

• poliosis [po″le-o′sis] loss of pigment in the hair; graying.

• poliovirus [po′le-o-vi″r s] the human poliomyelitis virus capable of infecting nonhuman primates. Causes paralysis due to encephalomyelitis in which motor neurons are selectively destroyed.

• Polish lowland sheepdog a medium-sized, cobby dog with a long, thick, shaggy coat that covers the eyes. The tail is very short or may be docked.

• Polish rabbit a small, compact breed of rabbits with short ears and a glossy coat in black, blue, chocolate, or white with ruby or blue eyes. In the UK, the name refers to a breed of small, fine-boned rabbits with a sleek, silky coat which are known in the US as Britannia Petite.

• polishing [pol′ish-ing] the final step in dental prophylaxis, performed after scaling to smooth the tooth surface and delay the rate of new plaque adhesion; carried out with a power-driven polisher, prophy cup, and prophy paste, which smooths the tooth surface and delays the rate of new plaque adhesion. Carried out with a mechanical polisher, prophy cup, and paste.

  • air p. blasting with particles, usually bicarbonate of soda, to polish the supragingival surfaces of the teeth.

• polishings byproduct of the rice industry; the material removed from the rice grain. Its quality varies depending on whether hulls are included; without them it is a high-protein supplement. With them it is largely fiber.

  P-67.

  

  Poll evil in horse

• poll [pōl] top of the head; the occiput.

  • p. evil a condition of horses involving inflammation of the supra-atlantal bursa commonly with infection with Brucella abortus, occasionally Brucella suis or Actinomyces spp. The bursa is swollen and painful initially and may rupture to discharge through a sinus.
  • p. gland steroid dependent glands in the male camel located in the neck (poll) region; secrete a substance (pheromone) used by the male for marking.
  • p. Hereford cattle see Hereford.
  • p. pad worn on top of the bridle to protect a horse’s poll while traveling.
  • p. presentation see poll presentation.
  • p. Shorthorn cattle see Shorthorn.

• Poll Dorset an Australian meat sheep produced by crossing the Dorset Horn with the Corriedale or Ryeland. A Downs sheep with all of their characteristics.

• pollakiuria [pol″ -ke-u′re-] abnormally frequent passage of urine.

• pollard fine protein-rich feed supplement for farm animals; a byproduct from the milling of wheat for flour. Called also shorts.

• polled [pōld] an individual animal of a normally horned breed, or a breed of a normally horned species, that does not grow horns. Selection for polledness amongst horned breeds has produced some remarkable breeds, e.g., polled Dorset, polled Hereford.

• polledness the hornless characteristic.

• pollen [pol′ n] the male fertilizing element of flowering plants.

  • p. allergy see canine atopy.

• Pollenia a genus of flies in the family Calliphoridae. Larvae occur in earthworms.

  • P. rudis a nuisance in animal accommodation because of their habit of clustering in roof spaces. Called also cluster fly. Other species are P. pediculata and P. pseudorudis.

• pollenosis [pol″ -no′sis] pollinosis.

• pollex [pol′ ks] [L.] thumb.

• pollinosis [pol″ľ-no′sis] an allergic reaction to pollen; hay fever.

• pollutants see environmental pollution.

• pollution [p -loo′sh n] defiling or making impure, especially contamination by noxious substances. See also environmental pollution.

  • anesthetic p. escape of inhalant anesthetic agents into the surgery environment has been implicated as a potential factor in increased rates of spontaneous abortion, birth defects, cancer, liver disease, loss of cognitive and motor skills, and drug dependence in operating room personnel. See also anesthetic scavenging.

• polo a game played between two teams of four mounted riders armed with polo sticks, consisting of wooden mallets on long sticks, and contesting the driving of a ball through a set of goals at either end of the ground which is 300 yd (274 m) long and 160 yd (146 m) wide. A match consists of six chukkas (eight in Argentina) each of 7 minutes.

• polo pony not a breed but a type of horse adapted for playing polo. The majority are Argentine thoroughbreds, and well over 15 hands high. They have a typical wiry quality, like Australian Stock horses and American and Canadian cutting horses.

• polocrosse a combination of polo and lacrosse played on horseback by teams of three players armed with polo-type sticks with nets attached on a field 146 m×54 m. The ponies used must not be taller than 15 hands.

• polonium (Po) [p -lo′ne- m] a chemical element, atomic number 84, atomic weight 210.

• poloxalene [pol-ok′s -lēn] a block polymer of ethylene and propylene oxides; it is a surfactant and given daily in the feed or as a drench. An effective preventer of ruminal tympany.

• Polwarth an Australian medium-woolled (22–25 microns) Merino (75%) crossed with a Lincoln (25%) sheep with at least five generations of inbreeding within the foundation stock.

• poly- word element. [Gr.] many, much.

• poly I:C polyinosinic acid–polycytidilic acid.

• poly(A) polyadenylate.

• poly(A) synthesis see polyadenylation.

• poly(A) tail see polyadenylation.

• polyadenitis [pol″e-ad″ -ni′tis] inflammation of several glands.

• polyadenosis [pol″e-ad″ -no′sis] disorder of several glands, particularly endocrine glands.

• polyadenylation [pol″e- -den″-la′sh n] the addition of up to 250 adenylate residues to the 3′ end of eukaryotic mRNAs to form a so-called poly(A) tail. The primary transcript is cleaved by a specific endonuclease that recognizes the sequence AAUAAAwhich is also referred to as a polyadenylation signal sequence. The poly(A) tail protects the mRNA from digestion with nuclease and greatly increases the efficiency of translation.

• polyamide [pol″e-am′īd] material used in the creation of nonabsorbable, synthetic, Nylon sutures.

• polyamines [pol″e-am′ēns] widely distributed cationic cell components especially abundant in rapidly proliferating cells. Major polyamines are spermidine and spermine but the diamine, putrescine is often grouped in this category. Multiple role in stabilizing intracellular negatively charged nucleic acids and membranes.

• polyandry [pol″e-an′dre] the mating of a female animal with more than one male.

• polyanethol sulfonate an anticoagulant and inhibitor of complement and lysozymes, included in bacterial culture media.

• polyangiitis [pol″e-an″je-i′tis] inflammation involving multiple blood or lymph vessels.

• polyarteritis [pol″e-ahr″t -ri′tis] inflammatory and degenerative lesions of the arterial walls in a number of isolated locations.

  • p. nodosa See periarteritis nodosa.

• polyarthric [pol″e-ahr′thrik] polyarticular.

• polyarthritis [pol″e-ahr-thri′tis] inflammation of several joints. More common in very young animals because of the frequency of navel infection and bacteremia and the immaturity of the arthrodial tissues. See also arthritis.

  • chlamydial p. caused by Chlamydia pecorum and characterized by joint enlargement, lameness, stiff gait, fever, conjunctivitis, a high morbidity, and mortality in young animals. There are also lesions and signs of involvement of other organs, e.g., pneumonia, encephalomyelitis, and interstitial focal nephritis. An important disease of feedlot lambs.
  • chronic villous p. chronic inflammation of the synovial membrane of several joints.
  • crystal-induced p. see gout, pseudogout.
  • feline chronic progressive p. see periosteal proliferative polyarthritis (below).
  • Greyhound p. an erosive joint disease of unknown etiology occurring in young Greyhounds. See greyhound polyarthritis.
  • immune-mediated p. see immune-mediated arthritis.
  • inherited p. a rare disease of young Akita dogs traced back to a single common ancestor, in which there is systemic illness with fever, lethargy, and peripheral lymphadenopathy, as well as severe polyarthritis.
  • p.–meningitis syndrome an immune-mediated, nonerosive polyarthritis and steroid-responsive meningitis-arteritis (SRMA) seen in Weimaraners and several other dog breeds. There is fever and spinal pain due to meningeal and intervertebral joint inflammation. Appendicular joint effusion may be subtle.
  • mycoplasmal p.Mycoplasma hyorhinis and M. hyosynoviae cause polyarthritis in pigs, the first in suckling pigs in which there may also be a serositis, the latter more common in older growing pigs. M. agalactiae bovis causes polyarthritis in feedlot cattle, M. mycoides var. capri causes polyarthritis and serositis in goats, and M. capricolum causes polyarthritis in goats and sheep. M. felis and M. spumans have been isolated from polyarthritis in cats and dogs, respectively.

    P-68.

    

    Periosteal proliferative polyarthritis of cats. There is active periosteal reaction, which spreads away from the epiphyses (arrows)

  • periosteal proliferative p. occurs in young, adult male cats as an acute, febrile illness accompanied by severe joint pain and stiffness, mainly in the hocks and carpi, followed by generalized stiffness, swollen joints, and ankylosis. Characterized by marked periosteal new bone formation. The disease is believed to be immune-mediated and associated with infection by feline leukemia virus and feline syncytium-forming virus. In a variant form, the onset is insidious, and the joint changes are erosive and deforming. Called also Reiter’s disease.
  • p.-polymyositis an immune-mediated, nonerosive polyarthritis, and chronic myositis seen most often in spaniel breeds. Affected dogs show waxing and waning stiffness, joint effusion, and poor exercise tolerance. There is progressive symmetric muscle atrophy.

• polyarticular [pol″e-ahr-tik′u-l r] affecting many joints; polyarthric.

• polyatomic [pol″e- -tom′ik] made up of several atoms.

• polybasic [pol″e-ba′sik] having several replaceable hydrogen atoms.

• polybrominated biphenyls see biphenyl.

• polybutester [pol″e-bū′tes-t r] a synthetic material used in suture materials. It has the advantage of being flexible, very strong, and forms knots well.

• polycarbophil [pol″e-kahr′bo-fil] see calcium polycarbophil.

• polychemotherapy [pol″e-ke″mo-ther′ -pe] simultaneous administration of several chemotherapeutic agents.

• polychlorinated biphenyls see biphenyl.

• polycholia [pol″e-ko′le- ] excessive flow or secretion of bile.

• polychondritis [pol″e-kon-dri′tis] inflammation of many cartilages of the body.

  • relapsing p. see auricular chondritis.

• polychromasia [pol″e-kro-ma′zh ] 1. variation in the hemoglobin con-tent of erythrocytes. 2. polychromatophilia.

• polychromatic [pol″e-kro-mat′ik] many-colored.

• polychromatocyte [pol″e-kro-mat′o-sīt] a cell stainable with various kinds of stains.

• polychromatophil [pol″e-kro-mat′o-fil] 1. a structure stainable with many kinds of stains. 2. a polychromatophilic erythrocyte.

• polychromatophilia [pol″e-kro″m -to-fil′e-] 1. the property of being stainable with various stains; affinity for all sorts of stains. 2. a condition in which the erythrocytes (usually immature), on staining, show various shades of blue (cytoplasmic RNA) combined with tinges of pink (hemoglobin); characterisitic of reticulocytes.

• polychromatophilic [pol″e-kro″m -to-fil′ik] having the property of polychromatophilia.

  • p. erythrocyte reticulocyte. An erythrocyte with blue-purple color.

• polychrome methylene blue [pol″e-krom] the preferred stain for a smear when the presence of anthrax bacilli is suspected. A positive result is a McFadyean reaction of a pink capsule around a blue bacillus.

• polychromemia [pol″e-kro-me′me- ] increase in the coloring matter of the blood; hyperhemaglobinemia.

• polycistronic [pol″e-sis-tron′ik] a single mRNA encoding several different polypeptide chains; typical of prokaryotes.

  • p. mRNAs a mRNA found in prokaryotes that encodes more than one protein. See also monocistronic mRNAs.

• polyclinic a veterinary clinic or hospital where a wide range of services are available, often with provision for after hours care; a term not commonly applied to veterinary premises, except in India.

• polyclonal [pol″e-klo′n l] derived from different cells; pertaining to several clones.

  • p. antiserum see polyclonal antibody.
  • p. gammopathy see polyclonal gammopathy.

• polyclonia [pol″e-klo′ne- ] a disease marked by many clonic spasms; called also polymyoclonus.

• polycloning site a short, engineered segment of DNA in a plasmid of phage vector that contains multiple cleavage sites for different restriction enzymes enabling a choice of the most appropriate restriction enzyme for cloning. Called also restriction site bank or polylinker site.

• polycoria [pol″e-kor′e- ] more than one pupil in an eye. Differentiated from pseudopolycoria in which the supernumerary “pupils” do not have a sphincter muscle on their border.

• polycrotism [pol-ik′r -tiz- m] the quality of having several secondary waves to each beat of the pulse.

• polycyclic [pol″e-sik′lik] having two or more usually fused chemical ring structures in their molecule.

• polycyesis [pol″e-si-e′sis] multiple pregnancy.

• polycystic [pol″e-sis′tik] containing many cysts.

  • p. kidney disease see polycystic kidney disease.
  • p. liver congenital anomaly in which cystic remnants of the bile duct occur in the liver; the bile duct is patent; seen in kittens, pups, piglets.
  • p. ovarian disease multiple thin-walled cysts in one or both ovaries of the mature bitch; may cause hyperestrogenism.
  • p. pancreas cystic pancreatic and bile ducts and polycystic kidneys may occur in the same patient.
  • p. renal disease see polycystic kidney disease.

• polycythemia [pol″e-si-the′me- ] an increase in the circulating red blood cell mass; may be used synonymously with erythrocytosis or reserved for neoplastic proliferation of marrow cell precursors.

  • absolute p. an increase in total hemoglobin and red cell mass with a normal plasma volume. Called also true polycythemia.
  • compensatory p. a physiological condition resulting from a decreased oxygen supply to the tissues, caused by living at high altitudes, heart disease, circulatory insufficiency or severe pulmonary disease, or the production of erythropoietin or erythropoietin-like compounds, as in polycystic kidney disease, hydronephrosis or renal neoplasms.
  • familial p. occurs as an autosomal recessive trait in Jersey cattle, and also in Japanese Black cattle.
  • primary p. see polycythemia vera (below).
  • pseudo-p. relative polycythemia.
  • relative p. apparent polycythemia resulting from loss of plasma and the hemoconcentration that follows or from splenic contraction. Called also spurious polycythemia, pseudo-polycythemia.
  • secondary p. see compensatory polycythemia (above).
  • spurious p. relative polycythemia.
  • p. vera a myeloproliferative disorder of unknown etiology. It occurs as an inherited defect in cattle and is a rare disease in dogs and cats. There is hyperplasia of the cell-forming tissues of the bone marrow, with resultant elevation of the erythrocyte count and hemoglobin concentration, and an increase in the number of leukocytes and platelets. Called also primary polycythemia, primary erythrocytosis.

• polydactylia [pol″e-dak-til′e- ] polydactyly.

• polydactylism [pol″e-dak′t l-iz- m] the presence of supernumerary digits; occurs as an inherited defect in cattle, cats, and some breeds of dogs; occurs not uncommonly also in horses.

• polydactyly [pol″e-dak′t -le] polydactylism.

• Polydelphis a genus of ascaridoid nematodes parasitic in the esophagus, stomach, and small intestine of pythons.

• polydioxanone a polymer of paradioxanone, used in a monofilament absorbable suture material.

• polydipsia [pol″e-dip′se- ] excessive thirst manifested by excessive water intake. The histories that accompany animal patients are often inaccurate on this point and should be qualified quantitatively.

  • compensatory p. one caused by an obligatory polyuria.
  • drug-induced p. diuretics, corticosteroids, salt, vitamin D, and megestrol acetate may cause a polyuria and, secondarily, a polydipsia.

    P-69.

    

    Polydactylism with the extra digit located at the level of the metacarpo-phalangeal joint

  • primary p. excessive water drinking in hyperactive, stressed dogs. See also psychogenic diabetes insipidus.
  • psychogenic p. horses confined in a stall and having little or no exercise may drink excessively from boredom, up to three times normal amounts. It may also occur in dogs, apparently from psychological causes, with large amounts of water a day being consumed and a corresponding polyuria with a large volume of dilute urine produced. Yet, when water intake is restricted, normal tubular function with concentration of urine is possible. See also psychogenic diabetes insipidus.

• polydysplasia [pol″e-dis-pla′zh ] faulty development of several tissues, organs, or systems.

• polyembryony [pol″e-em-bri′o-ne] the production of two or more embryos from one ovum, e.g., monozygotic twins. Armadillos are the only consistently polyembryonic mammals. It is a phenomenon in some helminths, e.g., Gyrodactylus spp., in which viviparous adults produce trematodes that are identical with themselves, and as larvae they carry larvae within their uteri that contain larvae in their uteri. The rate of reproduction can be very high. Also occurs in some insects in which fertilized eggs give rise to a number of larvae.

• polyemia excessive blood in the body.

• polyendocrine [pol″e-en′do-krin] pertaining to several endocrine glands.

  • p. gland failure see polyglandular syndrome.

• polyene [pol′e-ēn] chemical compound characterized by the presence of several conjugated double bonds.

  • p. antibiotics a group of agents, synthesized by Streptomyces spp., with antifungal activity; includes amphotericin B, nystatin, and candicidin.

• polyester [pol″e-es′t r] a multifilament strand of synthetic polymer.

  • p. base the plastic base on which the photographic emulsion is added to make an x-ray film.

• polyestrus [pol″e-es′tr s] having two or more estral cycles in each breeding season.

  • seasonally p. having estrous cycles only during part of the year. Increasing daylight hours stimulates cycling in spring and summer in mares and cats, but decreasing hours of daylight stimulates cyclicity in ewes and does in autumn.

• polyethylene [pol″e-eth′ -lēn] polymerized ethylene (CH−CH₂)_n, a synthetic plastic material, forms of which have been used in reparative surgery.

  • p. glycol (PEG) a polymer of ethylene oxide and water, available in liquid form (polyethylene glycol 300 or 400) or as waxy solids (polyethylene glycol 1540 or 4000), used in various pharmaceutical preparations as a water-soluble ointment base.
  • p. glycol electrolyte solution an osmotic solution used as a cathartic to empty the bowel in preparation for endoscopy and surgical procedures. Called also GoLytely.
  • p. suture one of the better monofilament fibers because of its good handling, low capillarity, high tensile strength, and longevity in tissue. It has only moderate knot-holding capacity.

• Polygala klotzchii [po-lig′ -l] South American plant in the family Polygalaceae; an unidentified toxin causes heavy mortality in cattle. Manifested by diarrhea, tremor, and incoordination. Called also jaranjinha.

• polygalactia [pol″e-g -lak′she-] excessive secretion of milk.

• polygamous [p -lig′-m s] as a male or female, having more than one mate.

• polygene [pol′e-jēn] .a gene member of a group of nonepistatic genes that act together additively to produce observable variation of a phenotypic trait; the individual gene’s effect on a phenotype is often too small to observe.

• polygenic [pol″e-jen′ik] pertaining to or determined by the interaction of several different genes.

• polyglactin 910 [pol″e-glak′tin] a synthetic absorbable multifilament surgical suture material, an alternative to catgut.

• polyglandular [pol″e-glan′du-l r] pertaining to or affecting several glands.

  • p. syndrome immune-mediated disease of more than one organ or endocrine gland in the animal, associated with the presence of autoantibodies. A heritable disorder in humans. In dogs, hypothyroidism and hypoadrenocorticism (Addison’s disease) are the most frequent findings. Called also Schmidt’s syndrome.

• polyglycolic acid (PGA) [pol″e-gli-kol′ik] a polymer of glycolic acid used as an absorbable suture material. Does not swell when wet and is nonantigenic. Is available coated in tissue lubricant, which improves passage through tissue. See also polyglactin 910.

• polyglyconate [pol″e-glik′ -nāt] a monofilament synthetic absorbable suture material with good tensile strength.

• Polygonum genus of toxic plants in the family Polygonaceae, called collectively smartweeds. Some cause nitrate–nitrite poisoning, some cause photosensitization; includes P. aviculare (wireweed), P. convolvulus (Fallopia convolvulus), P. hydropiper (water pepper), P. lapathifolium (Persicaria lapathifolium), P. orientale (Persicaria orientalis), P. pennsylvanicum (willow weed), P. persicaria (spotted persicaria).

• polygyny [p -lij′ľ-ne] 1. union of two or more female pronuclei with one male pronucleus, resulting in polyploidy of the zygote. 2. as a male, having more than one female mate.

• polygyria [pol″e-ji′re- ] a condition in which there is more than the normal number of convolutions on the external surface of the brain.

• polyhedral [pol″e-he′dr l] having many sides or surfaces.

• polyhidrosis [pol″e-hľ-dro′sis] hyperhidrosis.

• polyhydramnios [pol″e-hi-dram′ne-os] hydramnios.

• polyhydric [pol″e-hi′drik] a molecule containing more than two hydroxyl groups.

• polyhydroxydine an iodine-containing skin and wound disinfectant.

• polyinfection [pol″e-in-fek′sh n] infection with more than one organism at the one time.

• polyinosinic acid–polycytidylic acid synthetic double-stranded RNA polynucleotides, once considered for use as antiviral agents that act by inducing host interferon production. Abbreviated poly I–poly C; poly I:C.

• polyionic [pol″e-i-on′ik] containing a number of different ions, e.g., sodium, potassium, chloride, bicarbonate.

  • p. replacement solutions used in the treatment of animals with fluid and electrolyte deficit, the choice of solution to be used depending on the exact nature of the deficit.

• polyisobutene used as an additive in lubricating oil. When caught up in seabird feathers as a result of spills, it glues them together Responsible for some mass die-offs of seabirds

• polyleptic [pol″e-lep′tik] having many remissions and exacerbations.

• polylinker site see polycloning site.

• polymastia [pol″e-mas′te- ] the presence of supernumerary mammary glands or nipples; pleomastia.

• polymelia [pol″e-me′le- ] the presence of supernumerary limbs.

• polymelus [p -lim′-l s] an animal with supernumerary limbs.

• polymer [pol′ľ-m r] a compound, usually of high molecular weight, formed by combination of simpler molecules (monomers).

  • p.-fume fever see polytetrafluoroethylene.

• polymerase [p -lim′ r-ās] an enzyme that catalyzes polymerization, particularly of nucleic acids.

  • p. chain reaction see PCR¹.
  • RNA p. 1. an enzyme that synthesizes an RNA copy of the sequence in a limited region of DNA in a process known as DNA transcription. Called also DNA-dependent RNA polymerase. 2. a viral enzyme that synthesizes RNA from an RNA template during viral replication. Called also RNA-dependent RNA polymerase.
  • RNA-dependent RNA p. see RNA polymerase (above).
  • Taq p. a DNA polymerase that functions at high temperature; derived from the bacterium Thermus aquaticus and used in the polymerase chain reaction.

• polymeria [pol″e-mēr′e- ] a developmental anomaly in which there are supernumerary parts or organs of the body.

• polymeric [pol″e-mer′ik] exhibiting the character of a polymer.

  • p. biguanide see biguanides.
  • p. diet see polymeric diet.

• polymerization [p -lim″r-ľ-za′sh n] the combining of several simpler compounds to form a polymer.

• polymerized caprolactam a braided synthetic fiber used as a nonabsorbable suture material but only in animals. It has high tensile strength, modest knot-holding capacity, reduced capillarity because of a coating over the twisted fibers, and low tissue reactivity.

• polymicrobial, polymicrobic marked by the presence of several species of microorganisms.

• polymicrogyria [pol″e-mi″kro-ji′re- ] a congenital brain malformation caused by an abnormality in neuronal migration which results in the development of numerous small gyri. Reported as a congenital condition in standard poodles and cattle.

• polymorph [pol′e-morf] a colloquial term for a polymorphonuclear leukocyte.

• polymorphic [pol″e-mor′fik] occurring in several or many forms; appearing in different forms in different developmental stages.

• polymorphism [pol″e-mor′fiz- m] the quality of existing in several different forms. In genetics, the presence of genetic variation within a population.

  • balanced p. an equilibrium mixture of homozygotes and heterozygotes maintained by natural selection against both homozygotes.

• polymorphocellular [pol″e-mor″fo-sel′u-l r] having cells of many forms.

• polymorphonuclear [pol″e-mor″fo-noo′kle- r] 1. having a nucleus so deeply lobed or so divided as to appear to be multiple. 2. a polymorphonuclear leukocyte.

  • p. neutrophil (PMN) see neutrophil.

• polymorphous [pol″e-mor′f s] polymorphic.

• Polymorphus a genus of thorny-headed worms in the phylum Acanthocephala.

  • P. boschadis found in the posterior part of the small intestine of many domesticated and wild birds including ducks and fowls. Causes anemia, wasting, and enteritis, and heavy infestations cause death losses in colonies of aquatic birds.
  • P. botulus causes death losses in eider duck colonies.
  • P. magnus found in the intestines of wild anseriform birds.

• polymyarian the distinctive somatic musculature of Ascaris, Dracunculus, Filaria, and other related nematode genera in which there are more than five longitudinal muscle cells in each of the four quadrants of the body.

• polymyoclonus [pol″e-mi-ok′l -n s] 1. a fine or minute muscular tremor. 2. polyclonia.

• polymyopathy [pol″e-mi-op′ -the] any disease affecting a number of muscles simultaneously.

  • endocrine p. occurs in association with hypothyroidism or hyperadrenocorticism in dogs; they may present with muscle weakness or stiffness and pain.
  • hypokalemic p. see hypokalemic polymyopathy.
  • idiopathic p. a cause of acute pain, muscle weakness, and lameness or, in a chronic form, muscle atrophy, in dogs. May be generalized or affecting only certain muscle groups, particularly of the head.

• polymyositis [pol″e-mi″o-si′tis] inflammation of more than one muscle at once. See also polymyopathy.

  • equine p. see rhabdomyolysis.

• polymyxin [pol″e-mik′sin] a generic term for antibiotics derived from various strains of Bacillus polymyxa, several closely related compounds being designated by letters.

  • p. B a bacteriostatic and bactericidal antibiotic, effective mainly against gram-negative organisms. It is used as the sulfate salt, and is especially effective against Pseudomonas aeruginosa and Acinetobacter spp. It is used mostly in combinations with other antibiotics as a topical dressing including ophthalmic and aural preparations. It is not absorbed from the alimentary tract; systemic use is limited because of its nephrotoxicity and neurotoxicity.
  • p. E see colistin.

• polynesic [pol″e-ne′sik] occurring in many foci.

• polyneural [pol″e-noor′ l] pertaining to or supplied by many nerves.

• polyneuralgia [pol″e-n $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-ral′j] neuralgia of several nerves.

• polyneuritis [pol″e-n $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -ri′tis] inflammation of many nerves simultaneously.

  • p. equi see cauda equina neuritis.
  • idiopathic p. see Guillain–Barré syndrome, idiopathic polyradiculoneuritis.

• postinfectious p. see Guillain–Barré syndrome.

• polyneuromyositis [pol″e-noor″o-mi″o-si′tis] inflammation involving the muscles and peripheral nerves, with loss of reflexes, sensory loss, and paresthesias.

• polyneuropathy [pol″e-n $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$-rop′ -the] a disease involving several nerves. See also neuropathy.

  • acute idiopathic p. see idiopathic polyradiculoneuritis.
  • Alaskan malamute p. a hereditary neuromuscular disease that causes gait abnormalities and exercise intolerance, commencing from an early age, leading to paraparesis, and, in severe cases, tetraparesis. Involvement of the larynx may affect breathing. Caused by mutation in the NDRG1 gene; DNA testing is available.
  • familial p. see Boxer progressive axonopathy, hereditary neuronal abiotrophy of Swedish Lapland dogs, giant axonal neuropathy.
  • hypoglycemic p. associated with hyperinsulinism of β-cell insulinomas; immune-mediated mechanisms may also contribute. There is generalized muscle weakness, paraparesis, and tetraparesis.
  • hypothyroid p. a progressive lower motor neuron disease associated with hypothyroidism.
  • idiopathic p. see polyradiculoneuritis.
  • immune-mediated p. may occur in association with systemic lupus erythematosus in dogs; acute polyradiculoneuritis, chronic inflammatory demyelinating polyneuropathy, and paraneoplastic polyneuropathy are also thought to be immune-mediated.

• polyneuroradiculitis [pol″e-noor″o-r -dik″u-li′tis] inflammation of spinal ganglia, nerve roots, and peripheral nerves.

• polynomial [pol″e-no′me- l] a relationship between two variables such that y = a + bx + cx² + … qxⁿ. A straight line is y = a + bx. Any curve can be approximated with a polynomial formula.

• polynuclear [pol″e-noo′kle- r] 1. polynucleate. 2. polymorphonuclear.

• polynucleate [pol″e-noo′kle-āt] having many nuclei.

• polynucleosomes [pol″e-noo′kle-o-sōmz] a level of organization of nucleoprotein consisting of numerous nucleosomes joined by ‘linker’ DNA.

• polynucleotide [pol″e-noo′kle-o-tīd] any polymer of mononucleotides.

• polyodontia [pol″e-o-don′sh ] the presence of supernumerary teeth; called also hyperdontia. See also pseudopolyodontia.

  • heterotopic p. see ear cyst.

• polyol dehydrogenase [pol′e-ol de-hi′dro-j n-ās] see l-iditol dehydrogenase.

• polyolefin [pol″e-o′l -fin] synthetic material used for surgical sutures, e.g., in polyethylene and polypropylene sutures.

• Polyomaviridae a family of viruses, formerly part of the Papovaviridae.

• Polyomavirus [pol″e-o′m -vi″r s] the sole genus in the family Polyomaviridae. Polyomaviruses are nonenveloped, icosahedral in shape, 40–50 nm in diameter with a double-stranded DNA, ~5000 base pairs, circular genome. They are potentially oncogenic, but often persist as latent infections in a host without causing disease, but may produce tumors in a host of a different species or a host that is immunocompromised. The name polyoma derives fromthe observation that the viruses produce multiple (poly-) tumors (-oma).

• polyomavirus [pol′e-o-m -vi″r s] a member of the genus Polyomavirus.

  • avian p. the cause of highly fatal, acute, or chronic inflammatory diseases in several bird species and includes budgerigar fledgling disease; in contrast to polyomaviruses of other species, tumors are not seen in infected birds.

• polyonychia [pol″e-o-nik′e- ] the presence of supernumerary nails or claws.

• polyorchidism, polyorchism [pol″e-or′kľ-diz- m] the presence of more than two testes.

• polyosteomyelitis [ol″e-os″te-o-mi″ -li′tis] osteomyelitis at a number of sites in the one patient.

• polyostotic [pol″e-os-tot′ik] affecting several bones.

• polyotia [pol″e-o′sh ] the presence of more than two ears.

• polyovular [pol″e-ov′u-l r] pertaining to or produced from more than one oocyte, as polyovular twins.

• polyovulatory [pol″e-ov′u-l -tor″e] discharging several ova in one ovarian cycle.

• polyoxyethylenes [pol″e-oks″e-eth′ -lēns] alcohols used as emulsifiers in pharmaceuticals. They have low toxicity but may reduce growth rate.

• polyp [pol′ip] any growth or mass protruding from a mucous membrane. Polyps may be attached to a membrane by a thin stalk, in which case they are known as pedunculated polyps, or may have a broad base (sessile polyps). They are usually an overgrowth of normal tissue, but sometimes polyps are true tumors or masses of new tissue separate from the supporting membrane. Usually benign, they may lead to complications or eventually become malignant. Polyps may occur wherever there is mucous membrane: in the nose, ears, mouth, lungs, heart, stomach, intestines, urinary bladder, uterus, and cervix. Terminology includes location and/or contents, e.g., adenomatous, fibrous, gastric, tracheal.

  • nasal p. causes nasal obstruction in sporadic cases. Mycotic nasal granuloma of cattle is manifested by respiratory obstruction and polyps in the anterior part of the nasal cavity. They are eosinophilic granulomas containing spores and hyphae of the fungus Drechslera halodes (Setosphaeria rostrata). Also caused by nasal schistosomiasis. In cats, inflammatory polyps arise from mucosa of the nasal cavity or auditory canal.
  • nasopharyngeal p. occur in cats of any age; composed of inflammatory and fibrous tissue, originating most commonly in the auditory canal and extending variably into the middle ear, nasopharynx, and occasionally the external ear. They may cause sneezing, stridor, dyspnea, gagging, and difficulty eating or swallowing; signs of middle or external ear involvement can also predominate.
  • pharyngeal p. cause difficult swallowing and breathing. In cattle, they are pedunculated and capable of much movement and erratic clinical signs.

• polypathia [pol″e-path′e- ] the presence of several diseases at one time.

• Polypay a relatively new American breed of sheep developed as a multipurpose breed from four existing breeds using Finnish-Landrace for prolificacy and early puberty, Rambouillet and Targhee for fleece quality and long breeding season, and Dorset for mothering ability, carcass quality, early puberty, and long breeding season.

• polypectomy [pol″ľ-pek′t -me] excision of a polyp.

• polypeptide [pol″e-pep′tīd] a compound containing two or more amino acids linked by a peptide bond; called dipeptide, tripeptide, etc., depending on the number of amino acids present.

• polypeptide-oma see apudoma.

• polypeptidemia [pol″e-pep″tľ-de′me- ] the presence of polypeptides in the blood.

• polyphagia [pol″e-fa′j ] excessive ingestion of food. Polyphagia is a permanent objective with food animals in which carbohydrate engorgement and gastric dilatation are constant threats to health. In companion animals, it may be a sign of metabolic disease in which the nutritional requirements of the subject are greater than normal. See also diabetes mellitus, hyperthyroidism, Cushing’s syndrome.

• psychogenic p. in dogs and cats, may be related to stress or the introduction of a new, more palatable diet.

• polyphalangia [pol″e-f -lan′je-] excess of phalanges in a digit.

• polypharmacy [pol″e-fahr′m -se] 1. the administration of many drugs together. Called also shotgun pharmacy. 2. administration of excessive medication.

• polyphosphate a chemical preservative used as a 2–4% solution in the treatment of meat.

• polyphyodonty [pol″e-fi′o-don-te] teeth lost are replaced; there is an endless succession of teeth; seen in sharks, crocodilians, and snakes.

• polyplastic [pol″e-plas′tik] 1. containing many structural or constituent elements. 2. undergoing many changes of form.

• Polyplax [pol′e-plaks] a genus of sucking lice in the family Hoplopleuridae.

  • P. serrata common louse of laboratory mice. Transmits Mycoplasma spp. and Francisella spp.
  • P. spinulosa the common louse of the laboratory rat. Transmits Mycoplasma spp.

• polyplegia [pol″e-ple′j ] paralysis of several muscles.

• polyploid [pol′e-ploid] 1. characterized by polyploidy. 2. an individual or cell characterized by polyploidy.

• polyploidy [pol′e-ploi″de] the state of having more than two sets of homologous chromosomes; that is a multiple of the normal diploid number. Results from replication within a nucleus without nuclear division.

• polypnea [pol″ip-ne′ ] increased rate of respiration. See also hyperpnea.

• polypnoea see polypnea.

• polypodia [pol″e-po′de- ] the presence of supernumerary feet.

• Polypogon monspeliensis Australian grass in family Poaceae; causes poisoning when the grass seed head is infested with Anguina agrostis nematodes carrying Rathayibacter toxicus producing corynetoxins; causes incoordination, tremor, convulsions, sudden death, called Stewart’s Range syndrome. Called also annual beard grass.

• polypoid [pol′ľ-poid] resembling a polyp.

• polyporous [pol′e-por″ s] having many pores.

• polyposia [pol″e-po′zh ] ingestion of abnormally increased amounts of fluids for long periods.

• polyposis [pol″ľ-po′sis] the formation of numerous polyps.

• polypous [pol′ľ-p s] polyp-like.

• polypropylene [pol″e-pro′p -lēn″] a polyolefin available in monofilament form and used as a nonabsorbable surgical suture. Very popular as a vascular suture material as it does not incite a thrombotic reaction. Like most synthetics it has poor knot security, but it causes little tissue reaction and has very long life. It is also available in mesh form.

• polyptychial [pol″e-ti′ke- l] arranged in several layers; said of glands.

• polypus [pol′ľ-p s] pl. polypi [L.] polyp.

• polyradiculitis [pol″e-r -dik″u-li′tis] inflammation of the nerve roots.

• polyradiculoneuritis [pol″e-r -dik″u-lo-n$\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -ri′tis] an acute, idiopathic inflammation in dogs that predominantly affects the spinal nerve roots and to a lesser extent the peripheral nerves. The disease is acute in onset and produces signs of generalized lower motor neuron weakness with sensation largely spared. Recovery is usual but may take weeks or months. The cause is unknown but thought to be autoimmune in nature and the disease resembles Guillain-Barré syndrome in humans. In Australia a risk factor for developing the condition is the consumption of raw chicken, and an immune response triggered by exposure to Campylobacter bacterial species has been proposed. In the US, the disease is more common in Coonhounds, and one proposed theory for its etiology is that a component in raccoon saliva initiates the autoimmune response. Called also Coonhound paralysis.

  • protozoan p. canine neosporosis.

• polyribonucleotide [pol″e-ri″bo-noo′kle-o-tīd] a RNA molecule.

• polyribosome [pol″e-ri′bo-sōm] a string of individual ribosomes attached to a single messenger RNA molecule; they are formed for the translation of mRNA to proteins. Called also polysome. See also ribosome.

• polysaccharide [pol″e-sak′ -rīd] a complex carbohydrate that, on acid hydrolysis, yields many monosaccharides.

• polyscelia [pol″e-se′le- ] the presence of more than two hindlimbs.

• polyserositis [pol″e-se-ro-si′tis] general inflammation of serous membranes, with effusion.

  • porcine p. see Glässer’s disease, mycoplasmal polyarthritis.

• polysinusitis [pol″e-si″n s-i′tis] inflammation of several sinuses.

• polysome [pol′e-sōm] polyribosome. See also ribosome.

• polysomia [pol″e-so′me- ] doubling or tripling of the fetal body.

• polysomus [pol″e-so′m s] a fetus exhibiting polysomia.

• polysomy [pol″e-so′me] a state in which the cell nucleus contains at least one extra chromosome than in the normal diploid state.

• polyspermia [pol″e-spur′me- ] excessive secretion of semen. Distinguish from polyspermy polyspermy [pol″e-spur′me] fertilization of an ovum by more than one spermatozoon; occurring normally in certain species (physiological polyspermy) and sometimes abnormally in others (pathological polyspermy).

• polystichia [pol″e-stik′e- ] two or more rows of eyelashes on an eyelid.

• polystyrene [pol″e-sti′rēn] the resin produced by polymerization of styrol, a clear resin of the thermoplastic type.

  • sodium p. sulfonate a potassium exchange resin that may be administered orally or rectally in the treatment of hyperkalemia.

• polysulfated glycosaminoglycan (PSGAG) see glycosaminoglycan polysulfate.

• polysynaptic [pol″e-sľ-nap′tik] pertaining to or relayed through many synapses.

• polysyndactyly [pol″e-sin-dak′t -le] association of polydactyly and syndactyly.

• polysynovitis [pol″e-sin″o-vi′tis] synovitis at a number of sites in the one patient.

• polytef [pol′ľ-tef] the pharmaceutical name for Teflon, a polymer of polytetrafluoroethylene; used as a surgical implant material for many prostheses, such as artificial vessels and orbital floor implants, and for many applications in skeletal augmentation and skeletal fixation.

• polytenosynovitis [pol″e-ten″o-sin″o-vi′tis] inflammation of several or many tendon sheaths at the same time.

• polytetrafluoroethylene (PTFE) [pol″e-tet″r -floor″o-ro-eth′ -lēn] a synthetic material commonly used as a nonstick lining in domestic cooking utensils (frypans); called also Teflon. Overheating produces toxic fumes that cause an acute hemorrhagic pneumonitis and death in small caged birds, which are particularly susceptible. Called also polymer-fume fever, kitchen deaths. See also polytef.

• polythelia [pol″e-the′le- ] the presence of supernumerary nipples.

• polythiazide [pol″ľ-thi′ -zīd] a diuretic and antihypertensive agent.

• polytocous [po-lit′ -k s] giving birth to several offspring at one time.

• polytomogram [pol″e-to′mo-gram] the images produced by polytomography.

• polytomography [pol″e-to-mog′r -fe] tomography of tissue at several predetermined planes.

• polytrichia [pol″e-trik′e- ] hypertrichosis; excessive hairiness.

• polyunsaturated [pol″e- n-sach′r-āt″ d] denoting a fatty acid, e.g., linoleic acid, having more than one double bond in its hydrocarbon chain.

  • p. fatty acids see fatty acids.

• polyurethane [pol″e-u′r -thān] a synthetic material used for wound dressings and nonwoven vascular grafts.

• polyuria [pol″e-u′re- ] the formation and excretion of a large volume of urine, which may physiologic, pharmacologic, or pathologic. A history of polyuria in an animal is as unreliable as a history of polydipsia. A quantitative assurance that polydipsia is present suggests an error of renal tubular efficiency either as a result of toxic damage or an absence of the pituitary gland’s antidiuretic hormone.

  • compensatory p. see physiological polyuria (below).
  • pathological p. that caused by a disease of the kidney or disorder elsewhere in the body, e.g., diabetes mellitus or liver failure.
  • pharmacological p. is caused by administered fluids or medication, such as glucocorticoids or diuretics.
  • physiological p. the result of increased fluid intake; called also compensatory polyuria (above) and secondary polyuria.

• polyvalent [pol″e-va′l nt] multivalent; having more than one valence.

  • p. vaccine see polyvalent vaccine.

• polyvinyl [pol″e-vi′n l] a polymer of a normally monomeric compound, e.g., vinyl chloride.

  • p. alcohol technique a method of fixation and preservation of feces for later examination.

• polyvinylpyrrolidone (PVP) [pol″e-vi″n l-pľ-rōl′ľ-dōn] see povidone.

• POM prescription-only medicine; requires prescription by a licensed practitioner, such as a veterinarian.

• pomace the residue of fruits after juice is extracted and contains skins, pips and stalks; refers usually to grapes. Used as animal feed but useful only if dried. Called also pulp, marc.

• Pomax umbellata Australian plant of the family Rubiaceae; causes cyanide poisoning.

• Pomeranian a very small (3–7 lb), spitz-type dog with prominent eyes, a fox-like expression, erect ears, and a tail carried over the back. The long, straight coat is profuse and covers the body. The breed is predisposed to patent ductus arteriosus, patellar luxation, and tracheal collapse.

• pommel the high part at the front of the seat of the riding saddle.

• Pompe’s disease [pom′p ] see glycogenosis.

• Pomphorhynchus an acanthocephalan or thorny-headed genus of worms.

• P. laevis found in the intestine of freshwater and marine fish.

• POMR Problem-Oriented Medical Record.

• ponazuril a triazine anticoccidial with activity against Sarcocystis neurona, the cause of equine protozoal myeloencephalitis; approved as an oral paste for treating horses. Also used to treat protozoal and coccidial infections in kittens and puppies.

• Pongamia glabra Asian oil tree in plant legume family Fabaceae; toxicity is in cake made by expressing oil from seeds; contains an unidentified toxin, possibly the flavonoid karanjin, which causes hepatitis and nephrosis; called also Pongamia pinnata, poonga oil tree, karanja, Indian beech.

• pons [ponz] 1. that part of the metencephalon lying between the medulla oblongata and the midbrain, ventral to the cerebellum. See also brainstem. 2. slip of tissue connecting two parts of an organ.

  • p. varolii pons (1).

• pontine [pon′tīn, pon′tēn] pertaining to the pons.

• pontobulbar [pon″to-bul′b r] pertaining to the pons and the adjacent region of the medulla oblongata.

• pontocerebellar [pon″to-ser″ -bel′ r] pertaining to the pons and cerebellum.

• pontomedullary [pon″to-med′u-lar″e] pertaining to the pons and the medulla oblongata.

  • p. syndrome lesions in this area cause spastic, uni- or bilateral weakness to paralysis, depression of ipsilateral postural reactions, cranial nerve deficits, and sometimes alterations in consciousness.

• pontomesencephalic [pon″to-mes″ n-s -fal′ik] pertaining to or involving the pons and the mesencephalon.

• pony an adult equine animal of about 14 hands high. Breed definitions vary from 14 to 14.2 hands. The term is also used regardless of height, e.g., polo pony. The only safe procedure when writing a certificate for a pony, e.g., for sale, is to state the animal’s actual height, preferably in cm.

  • p. hypertriglyceridemia see equine hyperlipemia.
  • pit p. pony used in mines to haul mined rock. Breed varies as long as it is small, e.g., Shetland pony.

• Poodle a dog characterized by its thick curly coat and the intriguing, yet standardized, patterns created by clipping and grooming that usually leave isolated patches of profuse coat separated by areas that are closely clipped. Originally a retriever, these patterns are believed to have been intended to insulate joints and vital organs from cold water. Three size varieties are recognized as separate breeds: Standard, over 15 in. tall; Miniature, 10–15 in. tall; and Toy, which is less than 10 inches. The breeds are predisposed to otitis externa, progressive retinal atrophy, epilepsy, patent ductus arteriosus, cystinuria, patellar luxation, cataracts, distichiasis, and atlanto-axial luxation.

  • P. cat see Rex (1).

• Poole suction tube a tube with multiple holes at the end, which reduces plugging with fat and omentum.

• pooper-scooper a flat-bottomed shovel and separate spatula of corresponding size and shape, each on a long handle; used to collect dog feces from the ground, usually for disposal.

• poor performance syndrome a reduction in performance, especially of racehorses or sport horses, usually manifest over several occasions. Not to be confused with unjustified performance expectation syndrome of horse owners and trainers or lack of intrinsic athletic ability in which the horse consistently performs poorly or below expectations. Called also loss-of-form.

• poorness a state of agricultural animals of being thin or emaciated.

• popcorning playful jumping and running of a guinea pig.

• popliteal [pop-lit′e- l] pertaining to the area behind the stifle joint.

  • p. lymph node one of the palpable superficial lymph nodes; found behind the stifle joint, between the semimembranosus and semitendinous muscles; deep and superficial groups may occur, the latter being less frequent.
  • p. tendon transposition a surgical technique for reconstruction of the caudal cruciate ligament.

• popped knee see carpitis. A term usually reserved for diseases of horses.

• poppy [pop′e] member of the plant family Papaveraceae. Includes the genera Papaver, Chelidonium , Eschscholtzia , and Argemone.

• population [pop″u-la′sh n] all of the animals in a specifically defined area considered as a whole. The population may also be defined in modes other than geography, e.g., the cow population, a species specification, the nocturnal bird population.

  • binomial p. see binomial population.
  • p. cartogram a map of populations.
  • case p. see case population.
  • closed p. e.g., closed herd or flock; a population into which no introductions are permitted, including artificial insemination or embryo transfer; the population is genetically and/or hygienically isolated.
  • comparison p. see comparison population.
  • contiguous p’s the populations are separated but have a common border. Some diseases are very difficult to restrain from spreading from one population to the next.
  • control p. see control population.
  • p. density see population density.
  • experimental p. the population in which the experiment, or trial, is being conducted.
  • finite p. one capable of total examination by census.
  • general p. includes all classes and levels of animals (or plants) without any attempt to categorize them.
  • genetic p. see deme.
  • genetically defined p. one in which the ancestry of the animals in it is known.
  • p. genetics deals with the frequency of occurrence of inherited characteristics in a population.
  • infinite p. cannot be examined as a total population because they may never actually exist but are capable of statistical importance.
  • p. limitation restricting the growth of an animal population by desexing, by culling or by managemental means of interfering with reproduction.
  • p. mean the mean of the population.
  • p. numbers see population size (below).
  • open p. one in which immigration in and out is unrestrained.
  • parent p. the original population about which it is hoped to make some inferences by examination of a sample of its constituent members.
  • p. proportion the percentage of the population that has the subject characteristics.
  • p. pyramid a graphic presentation of the composition of a population with the largest group forming the baseline, the smallest at the apex.
  • p. at risk see risk population (below).
  • risk p. the population that is composed of animals that are exposed to the pathogenic agent under discussion and are inherently susceptible to it. Called also population at risk. High- or special-risk groups are those that have had more than average exposure to the pathogenic agent.
  • p. size actual counting of a total population, the census method, is not often possible in large animal populations. Alternatives are by various sampling techniques including area trapping, the trapping of all animals in an area, the capture–release–recapture method, the nearest neighbor, and line transect methods, The population size is expressed as the population present at a particular instant. Alternatively, it can be expressed as an animal-duration expression when the population is a shifting one, and it is desired to express the population size over a period (e.g., cow-day).
  • special-risk p. a population of animals that is especially likely to contract a disease because of some peculiarity of genetics or husbandry or because of geographic or climatic factors.
  • stable p. a population that has constant mortality and fertility rates, and no migration, therefore a fixed age distribution and constant growth rate.
  • standard p. a population not yet divided into classes; the population against which each of its constituent classes can be compared.
  • target p. in epidemiological terms the population from which an experimenter wishes to draw an unbiased sample and make inferences about it.

• poradenitis [por-ad″ -ni′tis] inflammation of lymph nodes with formation of small abscesses.

• porcine [por′sīn] pertaining to pig. See also hog¹, swine.

  • p. circovirus 1 a nonpathogenic virus.
  • p. circovirus 2 cause of postweaning multisystem wasting syndrome (PMWS) and porcine dermatitis and neuropathy syndrome (below).
  • p. congenital progressive ataxia and spastic paresis inherited autosomal recessive disease of swine manifest shortly after birth as a severe lethal neuropathy.
  • p. contagious pleuropneumonia see porcine pleuropneumonia.
  • p. deltacoronavirus disease first reported in 2014 in swine in the Midwestern US with rapid spread to the rest of the nation and Canada. Manifest with profuse watery diarrhea, vomiting, and dehydration associated with epithelial necrosis in the gastric pits and small intestine, and severe villous atrophy. High case fatality in neonatal piglets.
  • p. dermatitis and nephropathy syndrome (PDNS) caused by porcine circovirus type 2 (PCV2) and characterized by systemic vasculitis and glomerulonephritis. Occurs principally in grower/finisher pigs; clinical signs may include extensive purplish red, slightly raised lesions of various sizes and shapes over the thorax, abdomen, thighs, and forelegs. Case fatality is usually high. At postmortem, the kidneys are swollen, pale, and mottled with many small hemorrhages showing through the surface. There are enlarged lymph nodes and hemorrhages at multiple sites. The symptoms and postmortem findings are very similar to classical swine fever.
  • p. epidemic abortion and respiratory syndrome (PEARS) see porcine reproductive and respiratory syndrome (below).
  • p. epidemic diarrhea an important disease occurring in Europe and Asia and recently (2013) in North America, caused by an alphacoronavirus, porcine epidemic diarrhea virus (PEDV). Clinical syndrome is similar to Transmissible Gastroenteritis, the main clinical signs are watery diarrhea, vomiting, fast dehydration, and high piglet mortality.
  • p. epizootic diarrhea see porcine epidemic diarrhea, above.
  • p. hemagglutinating encephalomyelitis see hemagglutinating encephalomyelitis virus disease of pigs.
  • p. hepatitis E virus an enteric virus of pigs related to human hepatitis E that is not known to be pathogenic.
  • p. herpesvirus-1 see Aujeszky’s disease.
  • p. idiopathic chronic recurrent dermatitis a dermatitis observed only in sows and only in specific farrowing houses; affected sows recovered when moved from the houses; lesions consisted of annular macules and patches of erythema.
  • p. inclusion body rhinitis see inclusion body rhinitis.
  • p. intestinal adenomatosis see porcine proliferative enteropathy.
  • p. juvenile pustular psoriasiform dermatitis see pityriasis rosea.
  • p. lymphosarcoma a rare tumor in pigs but a high proportion of all porcine tumors. Caused by an oncovirus.
  • p. malignant hyperthermia see porcine stress syndrome (below).
  • p. myocarditis described in Australia affecting late-term and neonatal pigs and characterized with stillbirth, mummification, and preweaning deaths associated with a multifocal nonsuppurative myocarditis with myonecrosis. Believed associated with Bungowannah virus, a recently recognized pestivirus.
  • p. necrotic ear syndrome see necrotic ear syndrome.
  • p. parvoviral abortion see porcine parvovirus.
  • p. polioencephalomyelitis see porcine viral encephalomyelitis.
  • p. poliomyelitis see porcine viral encephalomyelitis.
  • p. proliferative enteritis complex see proliferative hemorrhagic enteropathy.
  • p. reproductive and respiratory syndrome (PRRS) an arterivirus disease of pigs first recognized in the US in 1987 and subsequently in many other countries; characterized by severe reproductive failure in sows and respiratory disease in young pigs and an influenza-like syndrome in grower finisher pigs. Acute phases of the disease typically last 2–3 months after which reproductive parameters often return to normal or exhibit decreases in the farrowing rate and irregular returns to estrus. Numerous strains of the virus are reported in the US and Europe with differences in pathogenicity. A disease notifiable to the OIE (see Table 20). Prior to a consensus, called also mystery swine disease, swine infertility respiratory syndrome (SIRS), porcine epidemic abortion and respiratory syndrome (PEARS), blue ear disease, and Heko-Heko.
  • p. respiratory coronavirus closely related but distinct from transmissible gastroenteritis (TGE) virus. Causes a mild, sometimes inapparent, respiratory infection, but no gastrointestinal disease
  • p. rubulavirus a paramyxovirus in the genus Rubulavirus. See blue eye disease.
  • p. SMEDI viruses enteroviruses or parvoviruses causing stillbirths, mummification, embryonic deaths, and infertility in sows.
  • p. streptococcal meningitis see streptococcal meningitis.
  • p. stress syndrome (PSS) is an acute death syndrome in pigs occurring usually after transportation, fighting, exercise or even high environmental temperature. If signs are observed they include increasing dyspnea, tremor, and stiffness, severe hyperthermia, and a rapid onset of rigor mortis after death. A genetic disorder, more common in breeds where there has been selection for muscling. Homozygous recessive (Hal gene) pigs are susceptible to develop the syndrome following stress. Heterozygous pigs are at risk to develop pale soft exudative pork (PSE) at slaughter. Halothane testing or genotyping can be used to determine the genotype of pigs for breeding. Called also herztod, pale soft exudative pork, malignant hyperthermia, transport death, acute back muscle necrosis.
  • p. ulcerative spirochetosis see ulcerative granuloma of swine.

• porcupine two families of rodents, the New World (Erethizontidae) and Old World (Hystricidae) porcupines have long, erectile spines or quills. All are nocturnal, some are arboreal, some live in burrows. The quills are a cause of major injury to predators.

  • p. fishDiodon spp. in the family Diodontidae. They have sharp spines and, like their relatives the pufferfish, can defensively inflate their body to a large size. Some species contain tetrodotoxin, a potent neurotoxin that causes hypotension, hypothermia, emesis, paralysis, and death. Called also balloonfish.

• pore [por] a small opening or empty space.

  • nuclear p. a group of proteins with a central hole through which molecules pass through a nuclear membrane.
  • dilated p. of Winer a benign follicular tumor that occurs on the head and neck of older cats; they resemble epidermal cysts with a keratin-filled, wide opening (pore).

• porencephalia [por″en-s -fal′e-] porencephaly.

• porencephalitis [por″en-sef″ -li′tis] porencephaly with inflammation of the brain.

• porencephalous [por″en-sef′ -l s] characterized by porencephaly.

• porencephaly [por″en-sef′ -le] development or presence of a fluid-filled cysts or cleft in the cerebral hemispheres, usually communicating with the subarachnoid space; may also communicate with the lateral ventricle.

• porging the process of removing all blood vessels from meat to be sold for consumption in Jewish households. This is a religious requirement.

• pork the fresh, uncured meat of the pig.

  • p. measles Taeniasolium and Cysticercus cellulosae.

• pale soft exudative p. see porcine stress syndrome.

• porker the class of pig judged to be most suitable for conversion to pork. The target age and weight vary too much between localities to make a general statement worthwhile.

• Porocephalus [por″o-sef′ -l s] internal parasites in the class Pentastomida and the family Porocephalidae.

  • P. clavatus, P. crotali, P. subulifer the adults of these wormlike arthropods are found in the respiratory passages of large snakes. Heavy infestations may kill the snakes.

• poroconidia conidia produced through a pore in the conidiophores. Seen in Alternaria spp.

• poroporo Solanumaviculare.

• porosis [p -ro′sis] a porous condition, usually rarefaction of bone.

• porosity [p -ros′ľ-te] the condition of being porous; a pore.

• porotomy [p -ro′t -me] meatotomy.

• porous [por′ s] penetrated by pores and open spaces.

• porphin [por′fin] the fundamental ring structure of four linked pyrrole nuclei around which porphyrins, hemin, cytochromes, and chlorophyll are built.

• porphobilinogen [por″fo-bľ-lin′ -j n] an intermediary product in the biosynthesis of heme. Not detectable in normal animals.

  • p. deaminase an enzyme involved in the condensation of porphobilinogen. Now called uroporphyrinogen I synthetase.

• porphobilinogen synthase [por″fo-bľ-lin′o-j n sin′thās] see aminolevulinate dehydratase.

• porphynuria [por″fin-u′re- ] see bovine congenital erythropoietic porphyria.

• porphyria [por-fēr′e- ] a group of inherited or acquired diseases in which there are abnormalities of porphyrin metabolism, with accumulation in the tissues and increased excretion of porphyrins.

  • bovine congenital erythropoietic p. inherited as an autosomal recessive trait in cattle; from birth, affected animals have varying degrees of reddish-brown discoloration of bones, teeth, and urine, anemia, and photosensitization, associated with a deficiency of the enzyme uroporphyrinogen III cosynthetase.
  • erythropoietic p. porphyria of genetic origin; a manifestation of involvement of erythropoietic tissue.
  • feline p. inherited as an autosomal dominant trait; affected cats have red-brown discolored teeth, urine, and tissues, severe anemia, and photosensitivity associated with a deficiency of uroporphyrinogen III cosynthetase. Called also feline congenital erythropoietic porphyria.
  • inherited p. the disease is inherited in cattle, swine, and cats and is similar to erythropoietic porphyria of humans. There are excessive amounts of porphyrins in urine and deposits in the bones and teeth causing a dark red-brown discoloration. The animals are very photosensitive and cannot live outside. See also hematoporphyrinuria, osteohematochromatosis.
  • pig p. an erythropoietic porphyria, similar to bovine congenital erythropoietic porphoryia, but inherited as a dominant trait. Discoloration of the teeth, bones, and tissues occurs, but not of the urine, except in severely affected cases. Photosensitization is not a feature. The enzymatic defect is unknown.

• porphyrin [por′f -rin] any of a group of iron- or magnesium-free cyclic tetrapyrrole derivatives that forms the basis of the respiratory pigments of animals and plants. Porphyrins, in combination with iron, form hemes.

  • p. test the presence of porphyrin in cultures of Haemophilus, Glaesserella, Histophilus or Taylorella spp. indicates that hemin is not required for growth.

• porphyrinogen [por″f -rin′-j n] partly reduced precursor form of porphyrin rings that can then have metals such as iron introduced to produce heme or other porphyrin structures.

• porphyrinuria [por″f -rľ-nu′re-] an excess of porphyrin in the urine. The urine is of normal color on voiding but darkens to a red-brown after exposure to light.

• Porphyromonas [por″fľ-ro-mo′n s] a genus of gram-negative, obligately anaerobic bacteria. Shot rods or coccobacilli, non–spore-forming, and nonmotile. Previously grouped in the genus Bacteroides. Members of the family Porphyromonadaceae. Involved in periodontal disease and gingivitis and a cause of dog and cat bite wound infections.

  • P. katsikii a cause of pygranulomatous pneumonia in goats.
  • P. levii associated with summer mastitis and pyometra in cattle.
  • P. macacae causes subcutaneous abscesses in cats.
  • P. salivosa now classified as P. macacae.

• porphyropsin [por″fľ-rop′sin] a visual pigment found in freshwater fish and some frogs.

• porpoise the smallest cetaceans, family Phocoenidae; related to whales and dolphins. Black on top, white belly, piscivorous, and an excellent swimmer. Includes the harbor porpoise (Phocoena phocoena), sometimes also known as the common porpoise, and the showy Dall’s porpoise (Phocoenoides dalli) that resembles the orca or killer whale.

• Porrocaecum a genus of roundworms in the family Ascarididae.

  • P. angusticolle found in birds of prey.
  • P. aridae found in the heron.
  • P. crassum found in the intestine of ducks; causes nasal discharge, diarrhea, anemia, and loss of weight.
  • P. decipiens found in the small intestine of the walrus.
  • P. depressum found in birds of prey.

• port [port] 1. a term given to an endoscopic sheath used for the passage of endoscopic equipment into the body. 2. the upward curve in a bar bit on a horse’s bridle.

• porta [por′t ] pl. portae [L.] an entrance or gateway, especially the site where blood vessels and other supplying or draining structures enter an organ.

  • p. hepatis the fissure on the visceral surface of the liver, where the portal vein and hepatic artery enter and the bile duct leaves. Called also portal fissure and transverse fissure.

• portacaval [por″t -ka′v l] pertaining to or connecting the portal vein and caudal vena cava.

  • p. anastomosis surgical, traumatic, or congenital defect resulting in an anastomosis between the portal vein and the caudal vena cava including a portal–azygos anastomosis, or the portal vein, and the hepatic artery resulting in portal hypertension. More commonly provides the physical basis for a portosystemic shunt.

• portal [por′t l] 1. an avenue of entrance; porta. 2. pertaining to an entrance or avenue of entrance; porta, especially the porta hepatis.

  • p.–azygos anastomosis a form of portacaval shunt with the portal vein bypassing the liver and emptying directly into the azygos vein.
  • p. biliary bacterial circulation a continuous normal circulation of bacteria brought to the liver in the portal vein from the gut and excreted back into the gut via the biliary system.
  • p. canal tissue space situated between three or more hepatic lobules; carries the blood and lymphatic vessels and connective tissue.
  • p. circulation circulation of blood from the capillaries of one organ to those of another; applied especially to the passage of blood from the gastrointestinal tract and spleen through the portal vein to the liver. See also circulatory system.
  • p. of entry the pathway by which bacteria or other pathogenic agents gain entry to the body.
  • p. fibrosis the formation of excess fibrous tissue (fibroplasia) in and around the hepatic portal triads usually as the result of chronic inflammation/irritation of the associated bile ducts. See also biliary fibrosis.
  • p. hypertension see portal obstruction.
  • p. obstruction obstruction of portal venous blood flow through external pressure on the portal vein, by abscess or tumor or by hepatic fibrosis constricting the hepatic vascular bed, causes interference with digestion and absorption and eventually venous return so that ascites and diarrhea develop.
  • p. system an arrangement by which blood collected from one set of capillaries passes through a large vessel or vessels and another set of capillaries before returning to the systemic circulation, as in the pituitary gland and liver. Includes the hepatic portal system consisting of portal vein and its tributaries from the stomach, intestine, pancreas, and spleen, the vessels into which the portal vein divides in the liver. See also renal portal system in birds.
  • p. systemic shunt see portosystemic shunt.
  • p. triad anatomically close association of interlobular bile duct, branches of hepatic artery, and portal vein.
  • p. vascular anomalies see portacaval anastomosis.
  • p. vein a short, thick trunk formed by the union of the caudal mesenteric and splenic veins; at the porta hepatis, it divides into successively smaller branches, following branches of the hepatic artery, until it forms a capillary system of sinusoids that permeates the entire substance of the liver. See Table 14.
  • p. vein hypoplasia congenital microscopic liver vascular abnormalities including small portal veins, most often affecting small dog breeds and rarely cats; hereditary in Cairn terriers. Can cause clinical signs similar to, but generally less severe than, those of portosystemic shunts, and usually presents later in life unless accompanied by a gross shunt. There is elevation of serum bile acids, and there may be poor growth, vomiting, diarrhea, and neurologic signs of hepatic encephalopathy. Called also primary hypoplasia of the portal vein (PVH) without portal hypertension; previously known as hepatic microvascular dysplasia.
  • p. vein obstruction acute, complete obstruction causes a syndrome similar to that of intestinal obstruction without signs suggesting liver involvement; partial occlusion causes shrinkage and eventual atrophy of the relevant section of the liver.
  • p. vein rupture rare complication of epiploic foraminal herniation; sudden death from internal hemorrhage results.
  • p. venule absence a congenital defect resulting in the development of multiple shunts within the liver, hepatoportal fibrosis, and ascites, general immaturity and hepatic encephalopathy.

• portio [por′she-o] pl. portiones [L.] a part, division or portion.

  • p. intermedia intermediate nerve, a root of the facial nerve.
  • p. vaginalis the portion of the uterus that projects into the vagina; the vaginal formix winds around it.

• portocaval [por″t -ka′v l] portacaval.

• portoenterostomy [por″to-en″t r-os′t -me] surgical anastomosis of the jejunum to a decapsulated area of liver in the porta hepatis region, and to the duodenum; done to establish a conduit from the intrahepatic bile ducts to the intestine in biliary atresia.

• portogram [por′to-gram] the image obtained by portography.

• portography [por-tog′r -fe] radiography or computed tomography (CT) of the portal vein after injection of contrast material.

  • jejunal p. contrast material is injected into a jejunal vein.
  • portal p. contrast material is injected into the into the cranial mesenteric vein or one of its branches, through a laparotomy.
  • splenic p. see splenoportography.

• portosystemic [por″to-sis-tem′ik] pertaining to the portal vein and the systemic circulation.

  • p. anastomosis see portacaval anastomosis.
  • p. shunt (PSS) a vascular communication between the portal and systemic vascular systems that permits circulation to bypass the liver. Congenital shunts may be intrahepatic, when there is failure of the fetal ductus venosus to close so that blood flow persists between the portal vein and the caudal vena cava; these are most common in large-breed dogs and may be inherited as in Irish wolfhounds; or extraheptic, in which there is communication, sometimes with multiple vessels, between the portal venous system and the systemic venous system, usually the abdominal vena cava. These are more common in cats and small-breed dogs, especially Maltese and Yorkshire terriers in which they are inherited. Clinical signs include poor growth from a young age, and combinations of gastrointestinal, lower urinary tract, and central nervous system signs. The latter include behavioral changes, blindness, head pressing, somnolence, postprandial seizures, and coma. Serum bile acid concentrations are greatly increased. Ammonium biurate crystals may be found in the urine.
  • p. vascular anomaly see portosystemic shunt (above) and portal vein hypoplasia.

• portosystemic vascular malformations [por″to-vas′ku-l r dis-pla′zh] circulatory malformations of the liver that include hepatic microvascular dysplasia and portosystemic vascular anomalies (portosystemic or portocaval shunts).

• Portuguese fishing dog [por′ch -gēs] see Portuguese water dog.

• Portuguese man-of-war, man-o’-war [por′ch -gēs] a floating colony of hydrozoa (Physalia physalis) with stinging filaments trailing from a central medusa that resembles its relatives the jellyfishes. Found in tropical and sub-tropical waters, it is known for its very painful stings, both in and out of the water. Records of poisoning in animals are very rare, but deaths do occur in infested colonies of farmed fish. Called also bluebottle.

• Portuguese podengo [por′ch -gēs] a sight and scent hound from Portugual. There are small (Pequeno), medium (Medio), and large (Grande) varieties and smooth or wire coat varieties. In the US, the Podengo Pequeno is recognized as a separate breed. A cerebellar cortical abiotrophy has been described in the breed. Called also Warren hound.

• Portuguese pointer [por′ch -gēs] a medium size, compact hunting dog with a square head, well-defined stop, and triangular ears. The coat is short and yellow or light brown. The tail may be docked.

• Portuguese sheepdog [por′ch -gēs] a medium-sized working dog with a long body, drop ears, long tail, and a long haircoat with goat-like texture.

• Portuguese water dog [por′ch -gēs] a medium-sized (35–60 lb), wellmuscled dog with characteristic swimming and fishing traits. The coat is profuse and may be either long, loosely waved, or short, harsh, and curled. In addition, the dog may be shown with a lion clip or a working-retriever clip. The breed gained celebrity status while living in the White House as the family dog of the Obamas. The breed is predisposed to distichiasis, GM1 gangliosidosis (storage disease), cardiomyopathy, and cataracts. Called also Portuguese fishing dog.

• Portulaca plant genus in the family Portulacaceae. Contains high concentrations of oxalic acid and sometimes nitrate, either of which can cause fatal poisoning in hungry ruminants. Manifested by recumbency and high mortality in sheep. Includes P. australis, P. filifolia, P. elatior, P. oleracea (pigweed, purslane), P. sp.aff. oleracea (munyeroo, inland pigweed).

• porus [por′ s] pl. pori [L.] an opening or pore.

  • p. acusticus externus the outer end of the external acoustic meatus.
  • p. acusticus internus the opening of the internal acoustic meatus in the cranial cavity.
  • p. opticus the opening in the sclera for passage of the optic nerve; better referred to as area cribrosa sclerae.

• posaconazole a triazole antifungal drug, structurally related to itraconazole. It has potent activity against Aspergillus spp, Candida spp. and molds.

• -posia word element. [Gr.] relationship to intake of fluids.

• position [p -zish′ n] a bodily posture adopted by an animal to facilitate breathing or a distended viscus or cavity, or to relieve pain by moving pressure from an organ. Used in obstetrics to describe the presentation of the fetus during birth.

• positional pertaining to position or posture.

  • p. nystagmus see positional nystagmus.

• positioning passive arrangement of the head, trunk or limbs in order to obtain the optimum x-ray image or to make a physical clinical examination, e.g., palpation of the abdomen.

  • p. equipment devices to hold limbs or head and neck in a predetermined position for radiographic or other examination.

• positive [poz′ľ-tiv] having a value greater than zero; indicating existence or presence, as chromatin-positive or coagulase-positive; characterized by affirmation or cooperation.

  • p. end-expiratory pressure (PEEP) in ventilation, the maintenance of a positive pressure in the airway at the end of the expiratory phase. A PEEP higher than the critical closing pressure holds alveoli open and can markedly improve the arterial Po₂ in patients with a lowered functional residual capacity (FRC), as in acute respiratory failure.

• positron [poz′ľ-tron] the antiparticle of the electron. When a positron is emitted by a radionuclide it combines with an electron and both undergo annihilation, producing two 511-keV gamma rays traveling in opposite directions. This effect is used in positron emission tomography (PET).

• posological [po-so-loj′ik- l] pertaining to posology.

  • p. table one listing drugs and their dosages.

• posology [po-sol′ -je] the study of doses of medicine or a system of dosage.

• possum [pos′ m] members of the large suborder Phalangeriformes, found in Australia, New Guinea, and Sulawesi, they were introduced to New Zealand where they are now considered pests, and can act as a reservoir for bovine tuberculosis. They are nocturnal, and most are arboreal. In urban settings, the common ringtail (Pseudocheirus peregrinus) and the common brushtail (Trichosurus vulpecula) possums forage ornamental garden plants and invade roof spaces. The American marsupial opossums, although sometimes called possums, are members of the separate order Didelphimorphia.

  • wobbly p. disease a fatal neurological disease of captive and free-living Australian brushtail possum populations in New Zealand; caused by an arterivirus.

• post- [pōst] word element. [L.] after, behind.

• postanesthetic occurring after general anesthesia

  • p. compartment syndrome a disease state caused by pressure-induced changes that result in decreased blood flow to muscle leading to ischemia, loss of function and sensation, and eventually necrosis; pressure changes can result from external forces during recumbency or from intrinsic muscle swelling due to overexertion as seen in humans. see also downer cow syndrome. See also postanesthetic myopathy (below), and myopathy.
  • p. morbidity disadvantageous events or disease states recognized in the postanesthetic period resulting from the patient being anesthetized. examples include prolonged recumbency, fracture, facial paralysis, pneumonia.
  • p. myonecrosis see postanesthetic myopathy (below).
  • p. myopathy muscle dysfunction associated with hypoperfusion resulting from anesthesia and prolonged recumbency. See also myopathy, postsurgical myopathy.

• postantibiotic effect (PAE) the continued suppression of antibacterial growth after the administration of antibiotic has ceased, and serum concentrations have fallen below the minimum inhibitory concentration.

• postdipping lameness lameness in sheep due to laminitis caused by infection with Erysipelothrix rhusiopathiae after dipping in insecticidal solutions that do not contain a bactericidal agent.

• postmilking teat disinfection see teat dip.

• post mortem postmortem.

• posttranscriptional RNA processing a series of enzymatic reactions that convert the primary transcript to a mature functional molecule. Processing includes: base modification, sugar modification, pyrimidine ring rearrangements, formation of helices, and tertiary conformations, additions to the 5′- and 3′-termini, specific exonucleolytic and endonucleolytic cleavages, complex cleavages with splicing, and the formation of RNA–protein complexes. The number, type, and order of the processing events varies with the RNA species.

• posttraumatic occurring as a sequel to trauma.

• posttraumatic sarcoma see feline posttraumatic sarcoma.

• postweaning pertaining to the period of about 2 weeks after weaning. Relates to the dam or the offspring.

  • p. anestrus a problem in sows, particularly those that have lost significant weight during lactation. See anestrus.
  • p. diarrhea a cause of serious losses in young pigs during the first 2 weeks after weaning, associated with viral and bacterial infection of the intestine following the loss of lactogenic immunity; a form of coliform gastroenteritis.
  • p. Escherichia coli diarrhea see coliform gastroenteritis.
  • p. growth check the sudden slowing of weight gain in piglets when they change from sow’s milk to prepared grain rations.

• postalbumin [pōst″al-bu′min] a peak on the electrophoresis pattern of serum proteins producing a shoulder on the cathodal side of the albumin peak.

• postauricular [pōst″aw-rik′u-l r] located or performed behind the auricle of the ear.

• postaxial [pōst-ak′se- l] behind or caudal to an axis; the ulnar aspect of the forelimb, and the fibular aspect of the hindlimb.

• postbrachial [pōst-bra′ke- l] on the caudal part of the upper forelimb.

• postcapillary [pōst-kap′ľ-lar′e] a venous capillary.

  • p. venule located in lymphoid tissue these are the site of recirculation of the lymphocytes from the blood to the lymphoid tissue.

• postcardiotomy [pōst″kahr-de-ot′ -me] occurring after open-heart surgery.

• postcava [pōst-ka′v ] the caudal vena cava.

• postcibal [pōst-si′b l] after a meal; postprandial.

• postcoital [post-koi′t l] after coitus.

• postcordial dorsal to the heart.

• postcornu the posterior horn of the lateral ventricle of the brain.

• postdiastolic [pōst″di- s-tol′ik] after diastole.

• postdicrotic [pōst″di-krot′ik] after the dicrotic elevation of the sphygmogram.

• postdistemper after an attack of canine distemper.

  • p. convulsions seizures due to encephalitis caused by the distemper virus.
  • p. encephalitis see old dog encephalitis.

• postduplication phase termination of DNA replication; histone and RNA synthesis occurs during this phase: called also postsynthesis or G₂ phase.

• postencephalitic [pōst″en″s -fal′ik] occurring after or as a consequence of encephalitis.

• postepileptic [pōst″ep″ľ-lep′tik] following an epileptic attack.

• posterior [pos-tēr′e- r] directed toward or situated at the back; opposite of anterior. In quadrupeds, applied only the eyeball, eyelids, lips, and inner ear.

  • p.–anterior with the x-ray beam passing from the back to the front, especially to the limbs. Term no longer in use, replaced by dorsal-ventral or cranial-palmar/plantar, as appropriate.
  • p. functional stenosis failure of pyloric outflow from the abomasum, as part of the syndrome of vagus indigestion in cattle.
  • p. limiting membrane of the cornea see Descemet’s membrane.
  • p. segment collective term for those parts of the eye posterior to the lens, including the vitreous body, retina, choroid, optic nerve, and sclera. Compare with anterior segment.
  • p. station trypanosomes one of the two types of development of trypanosomes. In this form, the metacyclic trypomastigotes accumulate in the hindgut of an arthropod vector and are passed out with the feces. Infection of the definitive vertebrate host occurs via the skin or skin wound. Called also Stercoraria. See also anterior station.

• postero- word element. [L.] relationship to the back, posterior to.

• posteroanterior [pos″t r-o-an-tēr′e- r] directed from the back toward the front (caudo-cranial).

• posteroexternal [pos″t r-o-ek-stur′n l] situated on the outside of a caudal aspect.

• posteroinferior [pos″t r-o-in-fēr′e- r] behind and below.

• posterolateral [pos″t r-o-lat′r- l] situated on the side and toward the caudal aspect.

• posteromedian [pos″t r-o-me′de- n] situated on the middle of a caudal aspect.

• posterosuperior [pos″t r-o-soo-pēr′e- r] situated behind and above.

• postganglionic [pōst″gang-gle-on′ik] distal to a ganglion.

  • p. axon an axon arising from a cell body within an autonomic ganglion, and distal to it.
  • p. fibers nerve fibers arising from cell bodies within an autonomic ganglion, and distal to it.

• postgraduate after completion of the first degree.

  • p. professional education continuing education, usually structured to provide a continuum of training in a particular segment of professional work, e.g., companion animal medicine and surgery.
  • p. studies include diplomas, certificates, and research higher degrees (master’s and PhDs), all in various disciplines and specialties.

• Postharmastomum a genus of intestinal flukes (digenetic trematodes) in the family Brachylaemidae.

  • P. commutatus (syn. P. gallinarum) found in the ceca of fowl and other birds and may cause typhlitis.
  • P. gallinum a parasite of chickens.
  • P. suis occurs in the small intestine of pigs but causes little apparent injury.

• posthepatitic [pōst″h -pat′ik] occurring after or as a consequence of hepatitis.

• posthetomy [pos-thet′ -me] circumcision.

• posthioplasty [pos′the-o-plas″te] plastic repair of the prepuce.

• posthitis [pos-thi′tis] inflammation of the prepuce.

  • enzootic p. of sheep see enzootic balanoposthitis.

• Posthodiplostomum a genus of flukes (digenetic trematodes) in the family Diplostomatidae. Numerous species.

  • P. cuticula the adults are found in the intestine of herons and kingfishers, but it is the second intermediate stage, the metacercariae, which occur in the skin, fin, cornea, and superficial muscles of fish that are pathogenic. They cause black spot disease of cyprinid fish, especially carp, and may cause some deaths.
  • P. minimum the metacercaria cause 1 mm diameter white cysts in most internal organs of many freshwater fish. Called also white grub. Herons are the definitive host.

• postholith [pos′tho-lith] a preputial concretion or calculus. See also preputial urolith.

• postsurgery starvation starving of horses after surgery can have the unfortunate sequel that the patient, intellectually incompetent, will gorge on bedding if not muzzled and develop gastric impaction.

• postholithiasis [pos′tho-lith-i′a-sis] see preputial urolithiasis.

• postictal [pōst-ik′t l] following a seizure.

• postiness the thickness and heaviness of the lower limbs of bulls and horses. The animal with thick, heavy legs is said to be posty.

• posting the rising of the rider to the trot.

• postmaturity [pōst″m -chōōr′ľ-te] the condition of a neonate after a prolonged gestation period.

• postmitotic [pōst″mi-tot′ik] occurring after or pertaining to the time following mitosis.

• postmortem [pōst mor′t m] performed or occurring after death.

  • p. decomposition the changes that occur after death of an animal. They include autolytic effects mediated by endogenous tissue enzymes, as well as the putrefactive effects of saprophytic microbes, and the destructive activity of insect larvae.
  • p. examination a careful dissection of a cadaver with the objective of deciding the cause of death. Called also autopsy or necropsy examination.
  • p. inspection that part of a meat inspection or food inspection process at an abattoir that is conducted after the animal has been killed and dressed. Supplements the antemortem examination.
  • p. report a detailed report of a postmortem examination of a cadaver, including a complete identification of the animal, the body condition, age, sex, species, breed, parity, and the changes observed.

• postnatal [pōst-na′t l] relates to the newborn in the period immediately after birth. A suitable subdivision is: early postnatal—within 48 hours of birth; delayed postnatal—2–7 days; late postnatal—1–4 weeks. See also perinatal, parturient disease.

  • p. diseases diseases that are more prevalent at this time in the animal’s life because of its small size, its immunological inadequacy, and its dependence on the dam for nourishment, protection from predators, and from inclement weather, especially protection from the cold.

• postnecrotic scarring [pōst″ n -krot′ik] a reaction to primary parenchymal injury in organs such as liver and pancreas; after the primary injury the resulting connective tissue undergoes condensation and scarification.

• postobstruction subsequent to relief of a uni- or bilateral obstruction of the urinary tract.

  • p. diuresis diuresis occurring after relief of the obstruction. Caused by the retention of natriuretic substances and extracellular fluid during the obstruction.

• postOp postoperative.

• postoperative [pōst-op′ r- -tive] after a surgical operation.

  • p. care care of the patient following a surgical procedure. Includes correct positioning relative to the surgery performed and the application of minimum pressure and strain on the operation site, maintenance of an open airway, maintenance of body temperature, moving from side to side if the recovery period is prolonged, maintenance of fluid and electrolyte balance, and monitoring for signs of developing shock.

• postoral [pōst-or′ l] in the back part of the mouth or somewhere in the digestive tract beyond the mouth.

• postparalytic [pōst-par″ -lit′ik] following an attack of paralysis.

• postpartum [pōst pahr′t m] [L.] after parturition; see also postparturient.

  • p. metritis in the cow, Trueperella pyogenes, Fusobacterium necrophorum, and Prevotella melaninogenica are major causative agents. Results in diminished fertility and milk yield and predisposes to chronic endometritis.
  • p. septic metritis commonly associated with retained placenta and poor uterine involution. Escherichia coli, Staphylococcus aureus, Trueperella pyogenes, Streptococcus spp., Pseudomonas aeruginosa, Proteus spp., rarely Clostridium spp. are common infections responsible for the putrid smell of the exudate and severe toxemia.

• postparturient [pōst-pahr-tu′re- nt] relates to the dam, in the period immediately after parturition.

  • p. debilitation the effects of pregnancy, parturition, and the onset of heavy lactation especially in animals with multiple offspring, coupled with the high incidence of metabolic diseases and disease of the uterus and the mammary gland at this time can cause serious debilitation which requires intensive management to correct.
  • p. endometritis inflammation of the endometrium as a result of infection introduced usually at parturition; one of the principal causes of infertility.
  • p. fever of sows see mastitis–metritis–agalactia.
  • p. hemoglobinuria a disease of high-producing dairy cows in the period of about a month after calving characterized by acute intravascular hemolysis, hemoglobinuria, pallor of mucosae, and a heavy mortality rate. Predisposed by a nutritional deficiency of phosphorus or copper.
  • p. hemolytic anemia see postparturient hemoglobinuria (above).
  • p. hypocalcemia see parturient hypocalcemia.
  • p. immunosuppression drain of antibodies in colostrum depletes maternal resources and reduces immune status.
  • p. paresis see parturient hypocalcemia.

• postprandial [pōst-pran′de- l] after eating. Called also postcibal.

  • p. alkaline tide see postprandial alkaline tide.

• postpuberal, postpubertal [pōst-pu′b r- l] after puberty.

• postpubescent [pōst″pu-bes′ nt] after puberty.

• postradiation [pōst-ra″de-a′sh n] following exposure to radiation.

• postrenal [pōst-re′n l] pertaining to those parts of the urinary system that, anatomically and physiologically, are distal to the kidney. Includes ureters, bladder, and urethra.

• postrotatory [pōst-ro″t -tor′e] occurring after the patient has been spun around passively.

  • p. nystagmus see postrotatory nystagmus.

• postshearing sheep in a state of susceptibility to cold stress immediately after shearing.

  • p. mortality death of sheep due to hypothermia, especially if they are thin and poorly fed, in the period immediately after shearing.

• postsphygmic after the pulse wave.

  • p. interval, p. period the short period of ventricular diastole, after the sphygmic period, and lasting until the atrioventricular valves open.

• poststenotic [pōst″st -not′ik] located or occurring distal to or beyond a stenosed segment.

• postsynaptic [pōst″sľ-nap′tik] distal to or occurring beyond a synapse.

• postsynthesis phase [pōst″sin′th -sis] see postduplication phase.

• postulate [pos′tu-lāt] anything assumed or taken for granted as a basis for reasoning.

• Koch’s p’s see Koch’s postulates.

• postural [pos′ch r- l] pertaining to posture or position.

  • p. reflexes, p. reactions reflexes that respond to changes of position of the body or head to maintain the eyes looking straight ahead and the poll–nose axis pointing similarly, e.g., hanging the animal by its hindlimbs should provoke a lifting of the nose, and if this is obstructed an upward rotation of the eye.

• posture [pos′choor] an attitude of the body. Good posture cannot be defined by any rigid formula. It is usually considered to be the natural and comfortable bearing of the body in normal, healthy animals. This generally means that in a standing position the body is naturally, but not rigidly, straight with the four legs evenly placed below the body, the back straight and the head held up so that the eyes look directly ahead. The position of the ears varies with the mental state of the animal. Continuous or frequent departure from this norm may indicate the need to look further for overt signs of disease. See also stance.

  • p. abnormality includes sternal or lateral recumbency, head deviation or rotation, head-pressing, dog-sitting, arched back.
  • kangaroo p. one which mimics the characteristic pose of kangaroos, sitting upright on the hindquarters with front legs held against the chest. Adopted by some cats affected by the spinal exostoses of hypervitaminosis A.
  • praying p. one in which the forequarters are close to the ground while the hindquarters are elevated by extension of the hindlegs. Assumed in dogs and cats, often because of abdominal pain.
  • sawhorse p. one in which the feet are placed wider apart than would normally be required to remain standing. Seen in tetanus and neurological diseases in which there are proprioceptive deficits.
  • submissive p. manifestation of appeasement behavior, for example with dogs, tail tucked, body lowered, head down, gaze averted, or rolling over and exposing the belly.

• postvaccinal [pōst-vak′sľ-n l] occurring after vaccination. Usually used in reference to an adverse reaction to the vaccine or occurrence of disease caused by the infectious agent contained in the vaccine because of an altered immune status in the recipient or a fault in the vaccine manufacture.

  • p. anaphylaxis see anaphylaxis.
  • p. hepatitis is most common after vaccination of horses against equine encephalomyelitis but also occurs after other vaccinations and in some cases at times unrelated to any vaccination. Clinically there is intense jaundice, gut stasis, oliguria, and stupor or mania.
  • p. sarcoma see feline vaccine-associated sarcoma.

    P-70.

    

    Praying posture in a dog with acute abdominal pain

• potable [po′t -b l] fit to drink.

• potash, potassa [pot′ash] chemically speaking, potassium hydrate, a strong caustic. In farming terms, potassium carbonate as it is mixed into fertilizers to redress a deficiency of potassium in the soil.

• potassa see potash.

• potassemia [pot″ -se′me-] kalemia.

• potassium (K) [po-tas′e- m] a chemical element, atomic number 19, atomic weight 39.102. The major intracellular cation. In combination with other minerals, potassium forms alkaline salts that are important in body processes and play an essential role in maintenance of its acid–base and water balance. All body cells, especially muscle tissue, require a high content of potassium. A proper balance between sodium, calcium, and potassium in the blood plasma is necessary for proper cardiac function. Alfalfa meal, molasses, and soyabean meal are good sources for herbivores. Causes of increased serum concentration (hyperkalemia) include renal failure, urinary tract obstruction, or rupture or hypoadrenocorticism.

  • p. acetate, bicarbonate, bitartrate, citrate, gluconate electrolyte replenishers, weak diuretics, and urinary alkalinizers. Some are also used as expectorants.
  • p. arsenite see Fowler’s solution.
  • p. bromide an antiepileptic drug used in dogs and cats, although cats have more adverse effects. Often used in conjunction with phenobarbital or where phenobarbital has been ineffective.
  • p. carbonate used commercially as a fertilizer.
  • p. channel see channel.
  • p. chloride a compound used orally or intravenously as an electrolyte replenisher.
  • p. cyanide may be present in industrial effluents. A potent cause of cyanide poisoning.
  • p. exchange resins an oral preparation administered to limit the amount of potassium available for absorption; used in the management of hyperkalemia. See also ion-exchange resin; sodiumpolystyrene sulfonate.
  • p. guaiacolsulfonate an organic potassium salt, used as an expectorant.
  • p. hydroxide (syn. potassium hydrate) used commercially as a caustic. In veterinary medicine used mostly for clearing skin scrapings in the diagnosis of ectoparasite infestation.
  • p. iodate used as a constituent of salt blocks and mixes to supplement the diet with iodine. Overdosing will cause iodism. It has also been used in the treatment of hyperthyroidism in cats.
  • p. iodide used as an iodide supplement as an expectorant and as an antithyroid agent. It has some antibacterial properties and has been used in the treatment of fungal granulomatous disease.
  • p. nitrate used commercially as a fertilizer and a meat preservative. Can cause nitrate poisoning or nitrite poisoning in ruminants.
  • p. nitrite a compound sometimes used in place of potassium nitrate. Overdosing causes methemoglobin formation and severe, sometimes fatal hypoxia.
  • p. nutritional deficiency extremely rare; causes poor growth, anemia, and diarrhea in pigs and calves. Electrocardiographic changes are also recorded. See also hypokalemia.
  • p. permanganate see permanganate.
  • p. phosphate a phosphorous supplement and a urinary acidifier.
  • p. sodium tartrate a compound used as a saline cathartic and also in combination with sodium bicarbonate and tartaric acid (historically, known as Seidlitz powders).

• potato Solanumtuberosum.

  • p. bushSolanum esuriale.
  • p. dermatitis scabby dermatitis on the lower limbs in cattle or water buffaloes on a diet heavily supplemented with potatoes over a period of some weeks.
  • p. poisoning see carbohydrate engorgement.
  • sweet p. Ipomoeabatatas.
  • p. weed Heliotropumeuropaeum.

• potbellied abnormal relative enlargement of the abdomen. Can be caused by increased size of viscera and contents, or diminution in volume of skeletal muscle, fat, and fascia due to malnutrition or wastage due to parasitism.

• potency [po′t n-se] power; especially (1) the ability of the male to perform coitus; (2) the power of a medicinal agent to produce the desired effects; (3) the ability of an embryonic part to develop and complete its destiny.

  • centesimal p. see centesimal scale.
  • decimal p. see decimal scale.

• potential [po-ten′sh l] 1. existing and ready for action, but not active. 2. electric tension or pressure.

  • action p. see action potential.
  • after-p. the period following termination of the spike potential.
  • membrane p. see membrane potential.
  • resting p. the potential difference across the membrane of a normal cell at rest.
  • spike p. the initial, very large change in potential of an excitable cell membrane during excitation.
  • zeta p. a net negative charge.

• potentiation [po-ten″she-a′sh n] enhancement of one agent by another so that the combined effect is greater than the sum of the effects of each one alone.

• postextrasystolic p. occurs in mammalian ventricular muscle after a premature contraction that is weaker than preceding beats; for several regular beats after the premature beats, the contractions are greater than normal.

• postsynaptic p. increased rate of discharge of a nerve cell that has been subjected to intensive stimulation. Appears to be related to the appearance of a greater number of dendritic spines.

• premature activation p. see postextrasystolic potentiation (above).

• potentization an expression of the number of dilution and succussion stages undertaken in the preparation of homeopathic medicines.

• Poteriostomum a genus of strongylid roundworms in the subfamily of Cyathostominae. Found in the large intestine of horses.

• Poth-Gold suture pattern a simple interrupted suture pattern used in intestinal anastomosis that is tied very tightly so that it cuts through the serosa, mucosa, and muscularis and remains holding the submucosa in apposition.

• potion [pō′sh n] a mixture of liquid medicines.

• Potomac horse fever see equine neorickettsiosis.

• potoroo member of the genus Potorous, small marsupial macropods native to Australia, known as rat kangaroo or kangaroo rat. All three living species are threatened, with Potorous gilbertii, Gilbert’s potoroo, critically endangered.

• Pott’s technique a surgical technique for management of tetralogy of Fallot involving a side-to-side anastomosis of the aorta and pulmonary artery.

• Potter–Bucky see Potter–Bucky grid, diaphragm, Bucky tray.

• potteries possible source of fluorine, used in glazes and art work, causing poisoning of livestock grazing on surrounding contaminated pasture.

• potto (Perodicticus potto) very small, nocturnal, arboreal, short-tailed primates, with long, slender bodies and limbs, in the family Lorisidae, They are native to equatorial Africa and primarily frugivorous. They are sometimes hunted for meat and have been found in the pet trade.

• Potts anastomosis a method of joining the aorta and the pulmonary artery, side-by-side, in the surgical management of tetralogy of Fallot.

• Potts-Smith scissors [pots] fine pointed scissors with various blade angles.

• Potts–Smith forceps long, fine-pointed, serrated jaw, tissue forceps useful for cardiovascular work.

• pouch [pouch] a pocket-like space, cavity or sac, e.g., one formed by bending back of the peritoneum on the surfaces of adjoining organs. See also bursa, pharyngeal pouch, marsupium.

  • abdominovesical p. the pouch-like reflection of the peritoneum from the abdominal wall to the ventral surface of the bladder.
  • adenohypophyseal p. see Rathke’s pouch (below).
  • cutaneous p. an invagination of the skin, especially a glandular invagination such as the infraorbital, inguinal, or interdigital pouch of sheep (see below).
  • guttural p. see guttural pouch.
  • infraorbital p. a cutaneous pouch rostral to the medial canthus of the eye, 0.5–1 in. deep, in sheep and many other ungulates. Called also lacrimal pouch.
  • inguinal p. an extensive cutaneous pouch in the inguinal region of male and female sheep. Called also mammary pouch.
  • interdigital p. a tubular invagination of the skin between the toes in sheep and some other cloven footed animals that anoints the hooves with its waxy secretion.
  • lacrimal p. see infraorbital pouch (above).
  • mammary p. see inguinal pouch (above).
  • pubovesical p. formed by a reflection of the peritoneum from the floor of the pelvis onto the neck of the bladder.
  • Rathke’s p. a diverticulum from the embryonic buccal cavity from which the anterior lobe of the pituitary gland is developed.
  • rectogenital p. the pouch contained by the extension of the peritoneal cavity into the pelvic cavity between the rectum and the uterus or the uterus masculinus in the male.
  • rectouterine p. the pouch formed by the extension of the peritoneal cavity into the pelvic cavity between the uterus (or the uterus masculinus in the male) and the bladder.
  • Seesel’s p. an outpouching of the embryonic pharynx rostrad to the pharyngeal membrane and caudal to Rathke’s pouch.
  • vesicogenital p. the peritoneal pouch between the bladder and the genital fold in the male, or the uterus in the female.

• poudrage [poo-drahzh′] [Fr.] surgical application of an irritating powder between serous membranes (e.g., pericardium or pleura) to promote their adhesion.

• poult a young turkey, from hatching until the time they can survive at ambient temperature.

• poultice [pōl′tis] from the Latin puls or pultes meaning ‘porridge’; a soft, moist mass of material, often hyperosmotic, that is applied to the skin or hoof to stimulate drainage of purulent material; a ‘drawing’ agent, typically applied warm in order to increase local blood flow and soften or macerate the skin/hoof.

• poultry [pōl′tre] farmed, domestic birds including fowls, turkeys, ducks, geese. For other words relating to domestic birds, see under avian.

  • p. hemorrhagic syndrome see hemorrhagic syndrome.
  • p. waste spilled feed, dried litter, and fecal residues from chicken houses can be used to provide a high-protein supplement feed for livestock. There are hazards, especially botulism, salmonellosis, and poisoning by feed additives such as copper and phosphorus. The material may also contain an unidentified hepatotoxin. Regardless of protein content, or potential hazards, esthetically it is not desirable for use as livestock food and, in the face of consumer concerns for food wholesomeness, is a remarkably stupid choice for use as a livestock feed. Called also dried poultry waste.

• pound [pound] 1. a unit of weight in the avoirdupois (453.6 g, or 16 ounces) or apothecaries’ (373.2 g, or 12 ounces) system. 2. said of the gait of a horse that strikes the ground hard with the front feet at the canter. 3. an enclosure or building maintained by a local government authority in which stray animals are kept until claimed by their owners. See also animal shelter.

  P-71.

  

  Infraorbital pouch (arrow) of the sheep

• Poupart’s ligament [poo-pahr′] inguinal ligament.

• pour-on a technique for the application of insecticides, in which a small amount of liquid is poured onto the animal’s back without any attempt to spread it over the surface. It is suited to systemic insecticides that are absorbed percutaneously or spread within the dermis.

• Pouret technique a surgical procedure for the correction of pneumovagina and urovagina in mares.

• pouters varieties of pigeon that can inflate their large crop; descended from the rock dove.

• povidone (PVP) [po′vľ-dōn] polyvinylpyrrolidone, a synthetic polymer used as a dispersing and suspending agent. It has also been used as a plasma volume expander.

• povidone–iodine (PVP-I) [po′vľ-dōn] a complex of iodine and povidone; used as a topical disinfectant. A common tradename is Betadine®.

• Powassan virus [po-wah′s n] see Flaviviridae.

• powder [pou′d r] a loose aggregation of very small particles obtained by finely grinding a solid.

  • dusting p. a fine powder used topically as a desiccant, dry lubricant, or vehicle for a topical insecticide.
  • glove p. sterile dusting powder used on surgical gloves to facilitate their application.

• powderpuff a Chinese crested dog with a full haircoat.

• powered driven by explosive or electrical power.

  • p. missiles used in euthanasia of animals. Includes conventional weapons such as revolvers, rifles, and shotguns, Greenough humane killers, and captive bolt pistols.
  • p. surgical instruments include saws, drills.

• pox [poks] a group of diseases caused by poxviruses and affecting primarily the skin and manifested by a characteristic progression of lesions from erythema to papule to vesicle to pustule to a round, reddish, raised scab about 0.5 in. diameter to a pock mark that remains at the site of lesions after healing. Includes buffalopox, camelpox, canarypox, cowpox, ectromelia (2), elephantpox, feline cowpox, fowlpox, goatpox, horsepox, monkeypox, parrotpox, pseudocowpox, rabbitpox, sealpox, sheeppox, swinepox.

• Poxvirales an order of viruses that contains poxviruses that are classified in the subfamilies Chordopoxvirinae, family Poxviridae, which includes viruses that infect animals, and Entomopoxvirinae, family Entomopoxviridae, which includes viruses that infect insects.

• Poxviridae [poks″vir′ľ-de] a family of viruses, the members of which are large, brick- or oval-shaped particles containing a double-strand DNA genome that replicate in the cytoplasm of cells. Divided into two subfamilies: Chordopoxvirinae (poxviruses that infect vertebrates) and Entomopoxvirinae (poxviruses that infect insects). There are 11 genera in the subfamily Chordopoxvirinae of which eight contain viruses of significant importance: (1) Orthopoxvirus, which includes, buffalopox, camelpox, cowpox, ectromelia (mousepox), horsepox, monkeypox, volepox, racoonpox, skunkpox, rabbitpox, vaccinia, variola; (2) Avipoxvirus, closely related viruses that include canarypox, fowlpox, juncopox, lovebirdpox, pigeonpox, quailpox, sparrowpox, starlingpox, turkeypox, and others; (3) Capripoxvirus, which includes goatpox, lumpy skin disease, and sheeppox viruses; (4) Leporipoxvirus, which includes squirrel, hare, and rabbit (Shope) fibroma viruses and myxoma viruses; (5) Suipoxvirus, which includes swinepox virus; (6) Parapoxvirus, which includes contagious ecthyma, bovine popular stomatitis, sealionpox, and pseudocowpox viruses; (7) Cervidpoxvirus, which contains deerpox virus; (8) Molluscipoxvirus that contains the Molluscum contagiosum virus. There are also unclassified poxviruses isolated from cats, elephants, lions, raccoons, and gerbils.

• poxvirus [poks′vi-r s] a virus in the family Poxviridae.

• PPD purified protein derivative; used for tuberculin testing.

• PP_i inorganic pyrophosphate.

• PPID see equine pituitary pars intermedia dysfunction (PPID).

• PPLO pleuropneumonia-like organisms. See also Mycoplasma.

• ppm abbreviation for parts per million; a weight-for-weight (w/w) concentration equal to 1 mg/kg or 1 g/tonne. Used most commonly to express the concentration of toxicants or trace elements in water, feeds, solvents, and tissues.

• PPN partial parenteral nutrition.

• PPR peste des petitis ruminants.

• PPV porcine parvovirus.

• P–R in electrocardiography, refers to the P and R waves.

  • P–R interval time period between the onset of the P wave and onset of the Q wave or, in the absence of a detectable Q wave, the beginning of the R wave.
  • P–R segment PR segment is the isoelectric tracing measured from the immediate end of the P wave to the beginning of the Q wave

• Pr chemical symbol, praseodymium.

• PRA progressive retinal atrophy.

• practice [prak′tis] the exercise of a profession.

  • advisory p. practice limited to giving advice, usually to farmers on the subjects of breeding, feeding, and housing in relation to maximum health maintenance and optimum production. Usually called a consultation practice.
  • association p. a group of individual practices contract to use common facilities, possibly franchised by a central practice. Similar to a group practice, having the benefits of a large group of veterinarians but maintaining independence of the individual practitioner.
  • branch p. the term has two meanings. 1. a separate enterprise connected to the parent practice only by having a common ownership. 2. a subsidiary practice utilizing the resources and staff of the parent practice. Usually attended only at specified, limited hours, with the opportunity for a client to go to the parent practice in an emergency. This is really a branch premises.
  • consultant p. practice as a specialist providing consultations and carrying out referrals for other veterinarians. Commonly used to refer to advisory practices (see above).
  • contract p. contracts are made with individual clients for work to be done for a flat fee or a sliding scale based on time spent, or per head in the risk population or a percentage of the profit.
  • corporate p. see company practice (above).
  • domiciliary p. house calls; a practice that is mostly domiciliary in that the veterinarian visits the patient in its own surroundings.
  • emergency p. a practice set up specifically to attend to emergencies that arise at times when most other surgeries are not available, e.g., nights, weekends, public holidays.
  • group p. individual veterinarians use the same facilities and provide mutual support, but each has his/her own clients and receives their fees after central costs are deducted.
  • illegal p. includes practice by veterinarians who are not licensed and practice by persons who are not veterinarians.
  • partnership p. partners are co-owners of a practice, not necessarily by equal shares, and have consequential proportional entitlement to the profits.
  • preceptor p. see preceptor.
  • primary accession p. a veterinary practice that does most of its work with primary accession cases—not a specialty practice.
  • private p. practice by a self-employed veterinarian who is obliged by convention to be available to the public, although it is accepted that such a veterinarian is entitled to limit the practice to a particular class of work, or to a geographical area or to a particular list of clients.
  • single enterprise p. a veterinary practice in which the veterinarian has only one client, usually a large industrial enterprise such as a feedlot.
  • special interest p. a practice in which the veterinarian limits the species or the kind of work that will be done, e.g., ‘practice limited to cagebirds’.
  • specialist p. see consultant practice (above).
  • subsidized practice a system of private practice in which some organization, local government, cooperative dairy company, a farmers’ club, etc., subsidizes the veterinarian. The method of subsidy varies from a salary with the right to private practice to a guaranteed total income with the subsidy making up any shortfall. A novel and successful method has been to provide the professional premises for the veterinarian at a minuscule rental.

• practicum a period of practical work, usually a defined requirement in a course of study, designed to supplement the classroom studies. Called also work placement.

• practitioner [prak-tish′ n- r] a person who practices a profession. This may be in one of the many forms of practice.

• private p. a veterinarian who conducts a private practice.

• public p. veterinarians employed in local, state, and federal government agencies.

• pradofloxacin a third-generation fluoroquinolone antibacterial drug. Increased effectiveness against Escherichia coli, Staphylococccus, and anaerobes. Similar to moxifloxacin.

• prae- for words beginning thus, see those beginning pre-.

• Prague ratter originally from Bohemia but now a popular breed in the Czech Republic, this very small dog (3.5–6.5 lb) with a very short coat in black and tan, yellow, and brown with yellow spots resembles a Miniature Pinscher. It has a keen sense of smell and, as the name suggests, was used for killing rats.

• prairie dog (Cynomys spp.) small, 12–in., 2-lb, gray-brown, herbivorous, diurnal rodent, living in burrows, in colonies or towns. Found in the US, Canada, and Mexico. In 2003, the prairie dog was associated with the first outbreak of monkeypox in humans in the US. Prairie dogs are very susceptible to bubonic plague (Yersinia pestis).

  P-72.

  

  Prairie dog

• pralidoxime (2-PAM) [pral″ľ-doks′ēm] 2-pyridine aldoxime methylchloride, a cholinesterase reactivator, effective against the nicotinic cholinergic effects of organophosphorus compounds such as organophosphate insecticides; it also has limited value in counteracting carbamate-type cholinesterase inhibitors.

• prallethrin a fourth-generation pyrethroid insecticide and repellent; used in combination with other chemicals.

• pramoxine, pramocaine [pră-mok′sēn] a topical anesthetic; acts by membrane stabilization and subsequent conduction blockade.

• prandial [pran′de- l] pertaining to a meal.

• praseodymium (Pr) [pra″ze-o-dim′e- m] a chemical element, atomic number 59, atomic weight 140.907.

• Prausnitz–Küstner (PK) reaction [prous′nits kēst′ner] a local hypersensitivity reaction induced by intradermal injection into a healthy person of serum from a hypersensitive individual. Subsequent injection of the antigen to which the donor is allergic results in a wheal-and-flare response.

• prawn common name for aquatic fresh or brackish water crustaceans.

  • fleshy p. Penaeuschinensis.
  • g. tiger prawn Penaeus monodon.

• praying posture see praying posture.

• prazepam [praz′ -pam] a benzodiazepine tranquilizer, similar to diazepam.

• praziquantel [pra″zľ-kwahn′t l] a widely used cestocide in dogs and cats. Has a very high efficiency against Echinococcus granulosus, removing all of the worms with a single dose.

• prazosin [pra′zo-sin] a postsynaptic α-adrenergic receptor blocker that acts as a peripheral vasodilator; used in the treatment of urethral spasm. Rarely used in the treatment of congestive heart failure.

• PRD progressive retinal degeneration.

• pre- word element. [L.] before (in time or space).

• pre-ejection period the interval from the onset of ventricular depolarization (not contraction) to the beginning of left ventricular ejection. Calculated by measuring the interval from the first deflection of the QRS complex to the aortic valve opening on cardiac ultrasound.

• pre-excitation premature excitation of a portion of the ventricle caused by stimuli passing along one of the auxiliary pathways of cardiac stimulation that are not subject to the same physiological delays as the A-V node. Characterized electrocardiographically by a short P–R interval and a wide QRS interval. See also accessory tract atrioventricular conduction, Wolff–Parkinson–White syndrome, Lown–Ganong–Levine syndrome.

• pre-mRNA precursor mRNA.

• preagonal [pre-ag′ -n l] immediately before the death agony.

• prealbumin [pre″al-bu′min] see transthyretin.

• preanesthetic [pre″an- s-thet′ik] 1. pertaining to preanesthesia. 2. an agent that produces a physiologic condition that facilitates induction of anesthesia. Acepromazine, atropine, diazepam are examples. 3. occurring before the administration of an anesthetic.

• preauricular [pre″aw-rik′u-l r] in front of the auricle of the ear.

  • p. alopecia an area of sparse haircoat located between the eyes and base of the ears in cats; a normal variation, but sometimes incorrectly interpreted as alopecia.

• preaxial [pre-ak′se- l] situated before an axis; the lateral radial aspect of the forelimb, and the tibial aspect of the hindlimb.

• prebetalipoprotein [pre-ba′t -li″po-pro′tēn] very low-density lipoprotein.

• prebetalipoproteinemia [pre-ba″t -lip″o-pro″te-ne′me-] hyperprebetalipoproteinemia.

• prebiotic [pre″bi-ot′ik] dietary fiber supplements, consisting of complex oligosaccharides, primarily fructooligosaccharides, mannooligosaccharides, xylooligsaccharides, and arabinooligosaccharides. Oligosaccharides are resistant to mammalian enzymatic digestion, but are readily fermented by enteric bacteria. Their inclusion in feeds is believed to promote nonpathogenic colonic bacterial growth, primarily of bifidobacteria and lactobacilli, and to maintain colonic health by production of beneficial short chain fatty acids with a decrease in intestinal pH, thus adversely altering the environment for pathogenic bacteria and reducing of colostridial numbers.

• prebloom the last stage of a plant’s growth, just before it blooms. It is at maximum bulk and the nutriment is still largely in the foliage. Subsequently, the nutritional mass moves out of the foliage and into the seeds and fruits.

• precancer [pre′kan-s r] a condition that tends to become malignant but does not necessarily do so, e.g., precancerous eye lesions in cancer-eye of cattle. See squamous cell carcinoma, neoplasia.

• precapillary [pre-kap′ľ-lar″e] a vessel intermediate between an arteriole and a capillary.

  • p. sphincters capillaries with a muscle layer that controls the flow of blood from the arterioles into the capillary bed.

• precardial [pre-kahr′de- l] pertaining to the precardium.

• precardium [pre-kahr′de- m] the area of the chest wall ventral to the heart.

• precava [pre-ka′v ] the cranial vena cava.

• preceptor [pre′sep-t r] an instructor or a private practice approved by a veterinary college to provide clinical training to veterinary students during externship blocks; see also preceptorship.

• preceptorship programs in which an approved veterinarian or credentialed technician (the preceptor) supervises students in a clinical setting, external to the veterinary school. Called also externship, practicum.

• prechordal [pre-kor′d l] situated in front of the notochord in the developing embryo.

• precipitant [pre-sip′ľ-t nt] a substance that causes precipitation.

• precipitate [pre-sip′ľ-tāt] 1. to cause settling of a soluble substance in solution. 2. a deposit of solid particles settled out of a solution. 3. occurring with undue rapidity, as precipitate labor.

• practolol [prak′to-lol] a β-adrenergic blocking agent with the same actions as propranolol.

• precipitation [pre-sip″ľ-ta′sh n] the act or process of precipitating.

  • p. test see precipitin reaction.

• precipitin [pre-sip′ľ-tin] an antibody to soluble antigen that specifically aggregates the antigen in vivo or in vitro to give a visible precipitate.

  • p. curve a plot showing the amount of antibody precipitated with increasing amounts of antigen added in a precipitin reaction.
  • double diffusion p. test see immunodiffusion.
  • p. reaction, p. test a reaction involving the specific precipitation of an antigen in solution by mixing with a specific antiserum in the presence of electrolytes. See also lattice theory.

• precipitinogen a soluble antigen that stimulates the formation of and reacts with a precipitin.

• precision [pre-sizh′ n] the quality of being sharply defined by virtue of exact detail, an important criteria of a diagnostic test. A precise test is free from random error and is a test where multiple analysis of a sample gives the same result. Precision is a requirement of accuracy but is not the same as accuracy.

• preclinical [pre-klin′ľ-k l] before a disease becomes clinically recognizable.

• precocial [pre-ko′sh l] said of some species of birds and mammals that give birth to young that are relatively well developed with open eyes, good covering of feathers or hair, and are independently mobile. This is usually associated with a longer gestation period. Seen in most ungulates and in guinea pigs. The opposite of altricial.

• precocity [pre-kos′ľ-te] unusually early development of physical and sexual traits.

• preconditioning [pre″k n-dish′ n-ing] preparation of 6–8 months old range-reared, recently weaned beef calves for entry into a feedlot and an intensive fattening program. Includes castration, dehorning, and branding 3 weeks before and all vaccinations 2 weeks before weaning, and weaning 3–4 weeks before sale or entry to the feedlot. During this postweaning period, the calf should become accustomed to feedlot feeds and conditions.

• precordial [pre-kor′de- l] pertaining to the precordium.

  • p. electric shock see cardioversion.
  • p. thump a sharp blow to the sternum to revive heart action is used in cardiac arrest in humans. It has not been of proven benefit in animals.

• precordium [pre-kor′de- m] area of the chest wall over which the heart contractions can be palpated and auscultated; typically it is found on the ventral third of the left chest wall caudal and medial to the elbow, which may be advanced cranially for better access.

• precorneal anterior to or external to the cornea.

  • p. tear film the thin layer of secretions from the conjunctival goblet cells and lacrimal, tarsal, and nictitans glands that covers the outer surface of the cornea and conjunctiva. Typically abbreviated to tear film or tears.

• precostal [pre-kos′t l] ventral or cranial to the ribs.

• precuneus [pre-ku′ne- s] pl. precunei [L.] a small convolution on the medial surface of the parietal lobe of the cerebrum.

• precursor [pre′k r-s r] something that precedes. In biological processes, a substance from which another, usually more active or mature substance is formed. In clinical medicine, a clinical sign or syndrome that heralds another.

  • p. fragments see Okazaki fragments.

• predation [pre-da′sh n] the characteristic of preying on other animals as a source of food. Can be a big cause of loss in animal flocks and herds, especially lambs. See also predatory.

• predator [prě′d -t r] an animal that derives its life support by predation.

• predatory [prě′d -to″re] pertaining to predator.

  • p. lesions dog attacks cause massive hemorrhages, much tissue disruption, broken bones; attack mostly thighs, flanks, lambs have crushed skulls; foxes attack tongue, lower jaw, tail area, thigh; coyotes eat a part of the carcass, crushing and tearing of larynx, fang marks in skin, and in lambs a crushed head and neck; crows attack eyes, tongue, anus, umbilicus of already immobilized victim.

• predentin [pre-den′tin] immature, uncalcified matrix of dentin produced by odontoblasts.

• prediabetes [pre-di″ -be′tēz] a state of latent impairment of carbohydrate metabolism in which the criteria for diabetes mellitus are not all satisfied; it is associated with a risk of progression to overt diabetes mellitus.

• prediastole [pre″di-as′t -le] the interval immediately preceding diastole.

• predicrotic [pre″di-krot′ik] occurring before the dicrotic wave of the sphygmogram.

• predicted difference predicting the improvement in production of the offspring as compared with that of the dam’s, which will result with the use of a particular sire. The estimate is based on the actual performance of the male in this regard, as measured on a sample of his offspring. Incorporates adjustments for environmental and management group effects and genetic trend. Called also expected progeny difference (EPD).

• predictive value a measure used by clinicians to interpret diagnostic test results. the diagnostic value of a test is defined by its sensitivity, specificity, predictive value, and efficiency. See also sensitivity, specificity, test efficiency.

  • positive p. v. 1. the probability that a patient with a positive test result really does have the condition for which the test was conducted. 2. the proportion of true positives to the total number of positives in the population. The higher the disease prevalence the greater the probability that a positive result will be truly correct.
  • negative p. v. 1. the probability that a patient with a negative test result really is free of the condition for which the test was conducted. 2. the proportion of the true negatives to the total number of negatives in the population.

• predigestion [pre″di-jes′ch n] partial artificial digestion of food before its ingestion into the body.

• predisposition [pre″dis-p -zish′ n] a latent susceptibility to disease which can be activated under certain conditions.

• prediverticular [pre-di″v r-tik′u-l r] denoting a condition of thickening of the muscular wall of the colon and increased intraluminal pressure without evidence of diverticulosis.

• prednisolone [pred-nis′ -lōn″] a synthetic glucocorticoid; an analog of hydrocortisone with three to five times the potency. Used as the crystalline form for oral administration, as the acetate or butylacetate for soft tissue injection or the sodium phosphate or sodium succinate for intravenous administration.

• prednisone [pred′nľ-sōn] a synthetic glucocorticoid; a prodrug converted into prednisolone.

• preen gland see uropygial gland.

• preformation theory [pre″for-ma′sh n] a defunct theory that each germ cell contains a complete microscopic replica of the organism.

• prefrontal [pre-fron′t l] situated in the anterior part of the frontal region or lobe of the brain.

• preganglionic [pre″gang-gle-on′ik] nerve fibers, usually autonomic ones located proximal to a ganglion.

• pregnable [preg′n -b l] capable of becoming pregnant.

• pregnancy [preg′n n-se] the condition of having a developing embryo or fetus in the body, after union of an ovum and spermatozoon. The duration of pregnancy in each animal species varies widely. See also gestation.

  • abdominal p. ectopic pregnancy within the peritoneal cavity.
  • p. associated glycoprotein (PAG) specific proteins, usually of placental origin, of value in laboratory diagnosis of pregnancy, especially in cattle.
  • p. diagnosis see pregnancy tests (below).
  • double p. see superfetation.
  • p. duration see gestation period.
  • early p. hormone (factor) identified in mice and several other species including sheep, cattle, pigs, humans; appears in the blood within a few hours of conception and persists for several weeks; identifiable by laboratory test. Known also as early conception factor (ECF). Commercial kits are available for pregnancy diagnosis based on detection of ECG, but their accuracy has been challenged.
  • ectopic p., extrauterine p. development of the fertilized ovum outside the cavity of the uterus. The site of implantation usually is one of the uterine tubes. Not recorded as occurring in animals.
  • p. edema see udder edema.
  • p. failure includes fetal resorption, fetal mummification, abortion, miscarriage.
  • false p. development of all the signs of pregnancy without the presence of an embryo. Commonly seen in bitches, 40–60 days after estrus, associated with the persistence of corpora lutea. There may be all the signs of impending parturition with mammary development, lactation, and behavior changes, including nest building and aggression. Tends to recur in the same bitch. Sometimes pyometra is a sequel. Called also pseudopregnancy, pseudocyesis.
  • hormonal p. diagnosis the use of any specific hormone to determine a state of pregnancy; can use chorionic gonadotropin (equine), pregnancy-specific proteins or pregnancy associated proteins (ruminants), progesterone (camelids), relaxin (canine).
  • multiple p’s. twins, triplets, and more in usually uniparous species.
  • phantom p. see false pregnancy (above).
  • p. prolonged see prolonged gestation.
  • p. rate (overall) the percentage of all services given to a group of females during a defined period which result in pregnancies (diagnosed at 42 days or more after service), or percentage of all females that become pregnant during a specified (usually seasonal) breeding period.
  • secondary p. toxemia pregnancy toxemia secondary to another condition which reduces the ewe’s or cow’s feed intake.
  • p-specific protein B a pregnancy diagnosis test available commercially; based on detection of a protein (PSPB) secreted by the trophoblastic ectoderm and present in the cow’s peripheral circulation at day 24 of gestation; persists in the circulation for 90 days after parturition. The test is used in all ruminants (domestic and wild) at various stages of pregnancy.
  • p. termination in the early stages of pregnancy prostaglandins are used; in the later stages corticosteroids are used. The efficacy of the various treatments varies between the species. See also parturition induction.
  • p. tests cover a wide range with different diagnostic techniques being most satisfactory in different species. Mare—ultrasound at 14–16 days, transrectal palpation of the uterus 30–35 days, serum gonadotropin concentrations at day 40–100. Cow—ultrasound at 27 days, transrectal palpation from 35 days onward; progesterone assay in milk at day 24 after breeding, pregnancy-specific protein B (PSPB). Ewes—ultrasound transrectal at 25 days, transabdominal after 40 days, rectal probe after 70 days, PSPB after 24 days. Sow—estrone sulfate content of the urine at 25 days, rectal examination at 30 days, ultrasound at 28 days. Bitch, queen—palpation through the abdominal wall in a cooperative patient at 21 days, radiographic examination at day 45, ultrasound at 35 days, (dogs) relaxin at 4 weeks.
  • tubal p. see ectopic pregnancy (above).
  • p. toxemia is recorded in ruminants. 1. Ewes. Pregnancy toxemia occurs only in the last month of pregnancy, most commonly in fat ewes carrying twin lambs, and in circumstances in which the feed supply is declining. Sheep have encephalopathy with blindness, muscle tremor, convulsions, metabolic acidosis, and a clinical course of 2–8 days, usually terminating fatally unless treated early. See also fat ewe pregnancy toxemia. 2. Cows. Fat cows in the last 6 weeks of pregnancy that suffer a sharp decrease in feed are subject. Dairy cows that calve in an excessively fat state and then are stressed nutritionally develop a syndrome very similar to pregnancy toxemia but called more commonly fat cow syndrome. In all of the diseases, there is blindness, recumbency, and severe ketosis. In early cases, there may be some excitation, even convulsions. 3. in guinea pig sows, particularly obese ones, uteroplacental ischemia caused by aortic compression and iliac arterial hypoplasia occurs in late pregnancy, causing lethargy, anorexia, and rapid death.

    P-73.

    

    Ewe with drought-induced pregnancy toxemia. The ewe is separated from other sheep in the flock, she can hear the approach of a person but cannot see and usually can be easily caught

• pregnane [preg′nān] one of the two major types of steroid hormone involved in female reproductive processes; includes progesterone.

• pregnane glycosides [preg′nān gli′ko-sīdz] neurotoxins isolated from plants in the family Asclepiadaceae such as Cynanchum, Sarcostemma, Marsdenia; cause muscle tremor, hypersensitivity, tetanic, and clonic seizures. Include cynafosides, sarcovimosides. Syndrome called cynanchosis (South Africa).

• pregnanediol [preg″nān-di′ol] a crystalline, biologically inactive dihydroxy derivative of pregnane, formed by reduction of progesterone and found especially in urine of pregnant women.

• pregnanediol-3-glucuronide a common urinary metabolite of progesterone used in assays of the hormone.

• pregnanetriol [preg″nān-tri′ol] a metabolite of 17-hydroxyprogesterone and a precursor in the biosynthesis of cortisol.

• pregnant [preg′n nt] having one or more developing embryo or fetus within the uterus; gravid; in calf, in lamb, in pig, in foal, in pup.

  • p. mare serum gonadotropin (PMSG) originates in the endometrial cups and present in the blood during the period 40 to 140 days of pregnancy. Used pharmaceutically to stimulate growth of follicles in inactive ovaries in adult animals, and in combination with prostaglandin to induce superovulation in cows that are acting as donors for embryo transfers. Now called equine chorionic gonadotropin (eCG).

• pregnenolone [preg-nēn′ -lōn] first intermediate in the synthesis of steroid hormones from cholesterol.

• prehemiplegic [pre-hem″ľ-ple′jik] preceding hemiplegia.

• prehensile [pre-hen′sil] adapted for grasping or seizing; usually said of tails (as in certain reptiles, New World primates opossum, and kinkajou), hands or feet, or nose (as in elephants).

• prehension [pre-hen′sh n] the act of grasping. Common usage is gras-ping food with the mouth or lips.

  • difficult p. needs to be classified into difficulty in approaching food, paralysis of the tongue or jaws, malapposition of incisor teeth, pain in the mouth, foreign body in the mouth, and defective development of the lips or tongue.

• prehormone [pre-hor′mōn] prohormone.

• prehypophysis [pre″hi-pof′ľ-sis] the anterior lobe of the hypophysis, or pituitary gland.

• preictal [pre-ik′t l] occurring before a seizure.

• preicteric [pre-ik-ter′ik] preceding the appearance of jaundice.

• preimmunization [pre-im″u-nľ-za′sh n] vaccination well in advance of the expected threat, e.g., 4 weeks before cattle go into a feedlot rather than the day of entry.

• preinvasive [pre″in-va′siv] not yet invading tissues outside the site of origin.

• Preisz–Nocard bacillus [prīs no-kahr′] see Corynebacterium pseudotuberculosis.

• prekallikrein [pre″kal-ľ-kre′in] Fletcher factor in blood coagulation. Precursor of plasma kallikrein that circulates in the blood. Acts in the initiation of the intrinsic component of coagulation.

• prekeratin [pre″ker′ -tin] a fibrous protein precursor of keratin synthesized by basal cells of the epidermis.

• prekeratocyte an abnormal erythrocyte form in which there is a cytoplasmic clear space caused by a hole; an intermediate form of a keratocyte. Called also blister cell.

• preleukemia [pre-loo-ke′me- ] a stage of bone marrow dysfunction that may progress to the development of granulocytic (myeloid) leukemia. Neoplastic cells are present in the bone marrow, but not in peripheral blood. It occurs in dogs and in cats, where it may be associated with feline leukemia virus infection. The disease is also called myelodysplastic syndrome with excess blasts.

• prelimbic [pre-lim′bik] in front of a limbus; refers usually to the limbus fossae ovalis (the margin of the fossa between the two atria).

• preload [pre′lōd] see cardiac preload.

• premalignant [pre″m -lig′n nt] a growth that is not yet malignant, but may or is likely to become malignant. Also called precancerous.

• premating uterus disinfection in some herd health programs; includes uterine infusion in all or selected cows with antibiotic or other antibacterial material. Previously practiced, but no longer recommended.

• premature [pre-m -chōōr′] born or interrupted before the state of maturity; occurring before the proper time.

  • p. heartbeats arise from foci from within the myocardium in either the atrium or ventricle or close to the A-V node (junctional premature beats). They may cause irregularity of the heartbeat but they can be accurately identified only by the use of an electrocardiograph. The clinical importance of intermittent premature heart beats is difficult to ascertain, but persistent occurrence could be indicative of heart disease.
  • p. ventricular complexes see premature heartbeats (above).
  • p. ventricular contraction (PVC) see premature heartbeats (above).
  • p. young a newborn animal born before the full term of its pregnancy but capable of maintaining an independent existence.

• prematurity [pre″m -chōōr′ľ-te] underdevelopment; the condition of being born prematurely.

  • p. and dysmaturity in foals term used for foals that show signs of prematurity and may be born prematurely, full-term, or even after a prolonged gestation, that may be small in size, slow to rise and suck, have a fine silky hair coat with soft ears and lips, incomplete ossification of the carpal and tarsal bones, a domed forehead, a red tongue, and increased susceptibility to hypothermia and failure of passive transfer of immunoglobulins.

• premaxilla [pre″mak-sil′ ] the incisive bone, the bone that bears the upper incisor teeth.

  • cleft p. see cleft lip. Cleft palate.

• premaxillary [pre-mak′sľ-lar′e] 1. situated in front of the maxilla proper. 2. incisive bone. 3. pertaining to the premaxilla.

• premaxillectomy [pre-mak″sľ-lek′t -me] surgical removal of a premaxilla, usually performed for radical excision of an oral neoplasm.

• premedication [pre″med-ľ-ka′sh n] preliminary medication, particularly medications to produce sedation, narcosis, or analgesia prior to the induction of general anesthesia, e.g., acepromazine, diazepam, morphine. See also preanesthetic.

• premilking 1. in the period immediately before commencing to milk the cow, ewe, or doe goat. 2. the act of milking the cow prior to parturition to reduce the severity of udder edema or to reduce the risk of parturient hypocalcemia (milk fever). Better methods of prevention are available. This practice will result in a decreased concentration of colostral immunoglobulins at parturition and a higher risk for neonatal calf disease.

  • p. udder preparation includes cleaning of the teats and udder so as to provide milk of good quality, massage to encourage let-down and fast milking, and physical examination and rejection of the first few streams of milk that are most likely to contain transient bacterial infections.

• premises a building or part of a building, including land and other appurtenances, especially mechanical services.

  • veterinary p. does not define whether the accommodation is classified as a hospital, or a clinic, or is less than those and does not fit any special criteria. Does indicate that the premises are used for veterinary purposes, e.g., branch premises indicates that the premises are used for veterinary work but is serviced from a main clinic at a distance and is not manned for sufficiently long periods each day to qualify as a branch practice.

• premix a finite mixture of nutritional supplements such as minerals and vitamins, usually combined with a carrier and ready for mixing with a total ration.

• premolar [pre-mo′l r] in front of (mesial or proximal to) the molar teeth, yet still behind (distal to) the canines. See also teeth.

• premorbid [pre-mor′bid] occurring before the development of disease.

• premucin [pre-mu′sin] mucin prior to its discharge from its goblet cell; gives the cell a foamy appearance.

• premunition [pre″mu-nish′ n] resistance to infection by the same or closely related pathogen established after an acute infection has become chronic, and lasting as long as the infecting organisms are in the body.

• premyeloblast [pre-mi′ -lo-blast″] a precursor of a myeloblast.

• premyelocyte [pre-mi′ -lo-sīt″] promyelocyte; progranulocyte.

• prenatal [pre-na′t l] preceding birth.

  • p. care care of the pregnant female before delivery of the neonate.
  • p. cytogenetic studies cytogenetic studies carried out on amniotic fluid cultures, the fluid being collected by amniocentesis, is not much used in veterinary medicine because of lack of knowledge of congenital disease linked to chromosomal abnormality. Could be used as a means of early sex determination.
  • p. infection infection of the fetus via an intact placenta, in the case of viruses, or via a placentitis in the case of bacterial or metazoan infections.
  • p. loss see abortion, stillbirth, early embryonic mortality, mummification.

• preneoplastic [pre″ne-o-plas′tik] before the formation of a tumor. See also precancerous.

• preOp preoperative.

• preoperative [pre-op′ r- -tiv] preceding an operation.

  • p. care the preparation of a patient before operation. The preoperative period may be extremely short, as with an emergency operation, or it may encompass several days during which diagnostic tests, specific medications and treatments, and measures to improve the patient’s general well-being are employed in preparation for surgery.
  • p. cleansing preparation of the patient and surgical personnel to minimize contamination of the wound. See also scrub (2).
  • p. scrub-up see surgical scrub.

• preoptic nuclei [pre-op′tik] nuclei in the anterior part of the hypothalamus.

• preoral [pre-or′ l] situated rostral to the mouth; in front of the mouth.

• preoxygenation [pre-ok″sľ-j n-a′sh n] administration of oxygen before the induction of anesthesia in order to increase oxygen tension in the upper airway in order to maintain oxygenation if apnea occurs.

• prep abbreviated form of ‘preparation’; most commonly used in reference to antiseptic skin preparation for surgery.

• preparalytic [pre-par″ -lit′ik] preceding paralysis.

• prepartum [pre-pahr′t m] just before parturition.

• prepatellar [pre″p -tel′ r] in front of (cranial to) the patella.

• prepatent [pre-pa′t nt] before it becomes manifest. Used with reference to infection with bacteria, viruses, and particularly helminth parasites.

  • p. period the period between infection of the host and the earliest time at which the causative agent can be recovered from the patient or, in the case of parasites, eggs, or larvae can be recovered from feces, urine, or blood. It is usually shorter than the incubation period but may be longer in some parasitic infestations, e.g., hookworm infestation in puppies.

• prepotent having great power; of the two parents, the one with greater power to transmit heritable characteristics to the offspring.

• preprandial [pre-pran′de- l] before meals. Abbreviation used in medical records and nursing notes.

• prepriming complex in DNA replication, an assembly of proteins that include dnaB–dnaC complex and proteins n, n′, n′′, and i, formed at an intermediate time during DNA replication.

• prepriming protein in the initiation of prokaryotic DNA replication, a group of proteins that bind to tetranucleotide motifs (T7 phage) prior to the synthesis of oligonucleotide primers by primase.

• preprocessing controls on an ultrasound machine, controls that alter the character of the incident sound beam, thus optimzing the resultant image.

• preprocollagen chain [pre″pro-kol′ -j n] primary translational product in the production of collagen.

• preproinsulin [pre″pro-in′su-lin] the precursor of proinsulin, containing an additional polypeptide sequence at the N terminus.

• preproparathyroid hormone [pre″pro-par″ -thi′roid hor′mōn] a precursor of proparathyroid hormone, synthesized on the ribosomes of chief cells; abbreviated pre-proPTH.

• preproprotein [pre″pro-pro′tēn] any precursor of a proprotein.

• prepuberal, prepubertal [pre-pu′b r- l] before puberty; pertaining to the period preceding gonadal maturity.

• prepubescent [pre″pu-bes′ nt] prepuberal.

• prepubic [pre-pu′bik] in front of the pubis.

  • p. tendon rupture occurs in late pregnancy in mares and cows. In horses, it is in inactive or older mares, especially of the draft breeds. The onset is usually acute and presents with painful ventral edema, followed by a pendulous “dropped” abdomen. Diagnosis is facilitated by transcutaneous ultrasonography.

    P-74.

    

    Mare with rupture of the prepubic tendon

• prepuce [pre′pūs] an invagination of skin that covers the free portion of the penis in the nonerect state. In horses, the invagination is a double one. In sheep and goats, and sometimes bulls, also called pizzle.

• preputial [pre-pu′sh l] emanating from or pertaining to the prepuce.

  • p. anastomosis a treatment for preputial prolapse in pigs involving resection of the prolapsed portion and joining of the skin and mucosal surfaces at the margin of the prolapsed tissue.
  • p. anulus the fibrous ring contained in the skin around the external orifice of the prepuce.
  • p. calculus top-shaped mass; may act as valve and obstruct preputial orifice.
  • p. diverticulitis inflammation of the preputial diverticulum in the pig.
  • p. diverticulum an evagination of the prepuce such as of the dorsal wall of the preputial cavity of the boar just inside the external preputial orifice. Called also preputial sac.
  • p. eversion because of injury or infection the skin lining the preputial cavity becomes swollen and edematous and prolapses through the preputial orifice where it is likely to undergo more injury. Most common in cattle and among them in polled animals that are likely to have a higher incidence of weak preputial muscles and therefore the most dependent pizzles. Called also preputial prolapse.
  • p. hypoplasia with concurrent smallness of other genitalia occurs with early castration and in intersex specimens.
  • p. inflammation posthitis.
  • p. prolapse seen in pigs and may be treated by replacement and use of a purse-string suture, or in more severe cases by preputial anastomosis (above).
  • ring method of p. amputation a surgical method of treating prepucial prolapse in bulls, using a rigid plastic ring as a framework for ligation.
  • p. sac see preputial diverticulum (above).
  • p. stenosis see phimosis and paraphimosis.
  • p. varicosities distended veins that often cause local distention of the prepuce in stallions but do not appear to interfere with breeding.

• preputiotomy [pre-pu″she-ot′ -me] incision of the prepuce of the penis frequently used to relieve phimosis.

• preputium [pre-pu′she- m] prepuce.

• prepyloric [pre″pi-lor′ik] just oral to the pylorus.

• prerace testing a procedure for testing a horse’s urine or saliva for drugs before the race is run with the objective of excluding the horse if the result is positive. This does not achieve the real objective of avoiding fraudulent betting coups, and because the logistics are difficult and expensive, and because postrace testing is still necessary in the same animal, prerace testing is not a common strategy.

• prerenal [pre-re′n l] in front of the kidney, used usually in a physiological sense rather than an anatomical one. The most important prerenal mechanism is severe reduction in renal blood flow and therefore glomerular filtration in shock, dehydration, and severe hemorrhage.

  • p. failure diminished or absent kidney function due to inadequate perfusion of the kidney.

• Presa Canario see Perro de Presa Canario.

• presacral [pre-sa′kr l] cranial to the sacrum.

• presby- word element. [Gr.] relationship to old age.

• presbyacusia [pres″be- -ku′zh] see presbycusis.

• presbyatrics [pres-be-at′riks] geriatrics.

• presbycardia [pres″be-kahr′de- ] impairment of cardiac function attributed to aging, with senescent changes in the body and no evidence of other cause of heart disease.

  P-75.

  

  Partial preputial eversion in a bull

• presbycusis, presbyacusia [pres″bľ-ku′sis] progressive, bilateral loss of hearing with advancing age; occurs in several animal species, especially old dogs.

• presbyopia [pres″be-o′pe- ] hyperopia; (diminution of near visual acuity) caused by reduced accommodation resulting from decreased elasticity of the lens, which occurs as a normal aging change.

• prescription [prě-skrip′sh n] a written directive, as for the compounding or dispensing and administration of drugs, or for other service to a particular patient. Any prescription for veterinary use relating to restricted drugs must be filled by a licensed pharmacist and can be authorized only by a licensed practitioner such as a veterinarian. There are four parts to a drug prescription. The first part, the ‘superscription’, is the symbol from the Latin recipe, meaning “take” or “take thou.” The second part is the ‘inscription’, which specifies the ingredients and their quantities. The third part is the ‘subscription’, which tells the pharmacist in which form to compound or dispense the medicine. The ‘signature’ is the last part, and it is usually preceded by an S or sig. to represent the Latin signa, meaning “mark.” The signature is where the veterinarian indicates what instructions are to be written on the outside of the package, in plain language, to tell the patient’s owner when and how to administer the medicine and in what doses. With medications a patient may require for prolonged periods without a change in dosage, the prescribing veterinarian may authorize a certain number of medication refills without further prescription; in such cases the number of refills is also specified on the prescription and on the medicine label. The pharmacist keeps a file of all the prescriptions he/she fills.

  • p. drugs drugs limited in their availability by law so that a prescription is needed to obtain them. Also called restricted substances.

• presentation [pre″z n-ta′sh n] lie; the relationship of the long axis of the fetus to that of the dam. In foals and ruminants, the normal presentation of a fetus during parturition is with the forelimbs extended forward so that the hooves are presented first, followed by the head between the forelimbs, followed by the trunk, abdomen, and lastly the hindlimbs extended backward, i.e., anterior presentation. In piglets, the usual presentation is the nose first followed by the shoulders with the forelimbs beside the trunk, followed by the hindlimbs extended backward. The nose of puppies and kittens is presented first with the front paws forward under the neck and chin.

  • anterior p. presentation of the front feet and limbs followed by the fetal head in labor.
  • breech p. presentation of the fetal buttocks and tail in labor.
  • funic p. presentation of the umbilical cord in labor.
  • poll p. the fetus is presented with the forelimbs retained and the neck flexed so that the poll is presented in the cervix.
  • posterior p. the hindfeet are presented followed by the hindlimbs and hindquarters and tail; a normal variation in dogs and pigs.
  • transverse p. at birth the fetus is presented at the pelvic inlet with its long axis running across the long axis of the pelvic canal in the dorsotransverse position. It is the back of the fetus that can be palpated. There are no fetal parts with which to effect a correction.
  • ventral head p. the fetus presents with the head and neck flexed beneath the body. Called also neck flexion.

• preservation 1. of food by any means which will inhibit the growth of microorganisms. Includes salting, wet pickling, drying, cold storage, smoking, vacuum packing, heating, gamma-radiation. 2. preservation of specimens for teaching purposes.

• preservative [pr -zur′v -tiv] a substance added to a product to destroy or inhibit multiplication of microorganisms.

  • food p. substances added to food for humans; hence they are not poisonous.
  • wood p. chrome–copper–arsenic, chlorinated naphthalene, creosote; poisonous to most animals. See also wood preservative.

• preslaughter tenderizing proposes the intravenous injection of a tenderizing agent, usually a proteolytic enzyme, a few minutes before slaughter. The concept is a repugnant one to most people, some consider that the effects are dubious, and some animals die of anaphylaxis immediately after the injection.

• presomite [pre-so′mīt] referring to embryos before the appearance of somites.

• presphenoid [pre-sfe′noid] the anterior portion of the body of the sphenoid bone (os presphenoidale).

• presphygmic preceding the pulse wave.

  • p. interval, p. period the first phase of ventricular systole, being the period immediately after closure of the atrioventricular valves and lasting until the semilunar valves open.

• pressor [pres′or] acting to increase blood pressure.

• pressor receptor [pres′or re-sep′t r] pressoreceptor.

• pressoreceptive [pres″o-re-sep′tiv] sensitive to stimuli due to vasomotor activity; pressosensitive.

• pressoreceptor [pres″o-re-sep′t r] a receptor or nerve ending sensitive to stimuli of vasomotor activity.

• pressosensitive [pres″o-sen′sľ-tiv] pressoreceptive.

• pressure [presh′ r] stress or strain, by compression, expansion, pull, thrust or shear.

  • arterial p. the blood pressure in the arteries. Usually measured in large arteries (e.g., aorta, carotid) or mid-sized arteries (radial, tibial, facial). See also wedge pressure below.
  • atmospheric p. the pressure exerted by the atmosphere, about 15 lb per square in. (2.17 kPa) at sea level.
  • capillary p. the blood pressure in the capillaries.
  • central venous p. (CVP) see central venous pressure. Usually measured in the cranial vena cava. Right atrial mean pressure is an indicator of central venous pressure.
  • cerebrospinal p. the pressure of the cerebrospinal fluid.
  • diastolic p. the lowest pressure recorded in the arterial blood pressure cycle. Represents the minimal pressure in the left ventricle that can maintain its ejection phase. See also blood pressure.
  • p. gauge a device attached to the outlet of gas cylinders to measure pressure inside the cylinder.
  • p. gradient the rate of increase (or decrease) in the magnitude of the pressure being measured.
  • intracranial p. (ICP) see intracranial pressure.
  • intraocular p. (IOP) the pressure exerted against the outer coats of the eye by its contents; typically reduced in uveitis and elevated in glaucoma.
  • p. load see flowload.
  • mean circulatory filling p. a measure of the average (arterial and venous) pressure necessary to cause filling of the circulation with blood; it varies with blood volume and is directly proportional to the rate of venous return and thus to cardiac output.
  • p. natriuresis thought to participate in regulating the volume of extracellular fluid levels when the normal neurohumoral mediators are impaired; the increase in water and sodium ion excretions that occurs when blood pressure is elevated because of an increase in the circulating blood volume.
  • p. necrosis necrosis of tissue caused by exclusion of circulation by external compression, e.g., in prolonged recumbency, or due to too-tight bandage, collar, harness.
  • negative p. pressure less than that of the atmosphere.
  • oncotic p. the osmotic pressure of a colloid, including proteins in solution. Usually acts to pull water into the blood; low oncotic pressure can result in fluid accumulation in the tissues (edema).
  • osmotic p. the potential pressure of a solution directly related to its solute osmolar concentration; it is the maximum pressure developed by osmosis in a solution separated from another by a semipermeable membrane, i.e., the pressure that will just prevent osmosis between two such solutions.

    P-76.

    

    Pressure necrosis. Pressure sore over the lateral hock of a dog. Bassert, J.M., McCurnin, D.M., McCurnin’s Clinical Textbook for Veterinary Technicians, 7th ed, Saunders, 2010

  • partial p. the pressure exerted by a specific gas in a mixture of gases. Because the amount of the gas dissolved in a liquid is proportional to the pressure of the gas on the fluid, the concentration of a gas in a fluid is expressed as its partial pressure.
  • positive p. pressure greater than that of the atmosphere.
  • pulse p. difference between systolic and diastolic pressures in arteries.
  • p. receptors e.g., the blood pressure receptors in the aortic arch and the carotid sinus.
  • p. sore see decubital ulcer.
  • systolic p. the highest reading in the arterial blood pressure cycle. A reflection of the ejection pressure of left ventricular systole, and the elasticity of the arterial system.
  • venous p. the blood pressure in the veins. See also central venous pressure.
  • wedge p. pressure in a small pulmonary artery vessel measured by wedging a catheter with an inflated balloon tip, such as a Swan–Ganz catheter, and providing an indirect measure of mean left atrial pressure.
  • p. wrap bandages which apply pressure to underlying tissues; used after trauma to limit the development of edema, and in the management of lymphedema.

• pressure points parts of the body subject to pressure when the animal is recumbent, wearing harness or saddlery, or during restraint. Usually bony prominences such as the point of the hock, hip, shoulder, elbow, and lateral aspects of limbs. These are predisposed to callus formation, ulceration, development of pressure sores, pyoderma, and granulomas.

• presternal [pre-ster′n l] ventral, or rarely, cranial to the sternum.

  • p. calcification calcification of originally fat necrotic lesions in the brisket of cattle resulting from repeated trauma caused by lying down or by pressure by feed trough. Called also putty brisket.

• presternum [pre-stur′n m] the manubrium; the cranial part of the sternum.

• presuppurative [pre-sup′u-ra″tiv] preceding suppuration.

• presuturing [pre-soo′ch r-ing] the placement of large sutures in the skin over a lesion 12–24 hours before it is to be surgically removed. This allows for stretching of skin that assists in closure of the defect at the time of surgery.

• presymptomatic [pre″simp-to-mat′ik] existing before the appearance of clinical signs.

• presynaptic [pre″sľ-nap′tik] situated or occurring proximal to a synapse.

• presystole [pre-sis′to-le] the interval in the cardiac cycle just before systole.

• presystolic [pre″sis-tol′ik] pertaining to presystole.

• pretarsal [pre-tahr′s l] dorsal to the tarsus.

• pretibial [pre-tib′e- l] cranial to the tibia.

• prevalence [prev′ -l ns] the total number of cases of a specific disease in existence in a given population at a certain time, i.e., prevalence. In a herd, disease prevalence is a function of incidence, duration of disease and rate of loss or removal of affected animals. See also cross-sectional study.

  • instantaneous p. the prevalence at a particular moment. Called also spot prevalence.
  • period p. the number of cases of a disease which occur during a specified period, e.g., annual, lifetime, as a percentage of the total or average total number of animals at risk during the same period.
  • point p. as for period prevalence (above) except that the assessment is made at a specific point in time rather than over a period, a rather impractical exercise.
  • point p. rate the proportion of the animals in a population at a point in time which are affected by the subject disease at that point. Called also instantaneous prevalence.
  • p. rate the number of patients who have the disease at a particular time, divided by the population at risk of having the disease at that time.
  • spot p. see instantaneous prevalence (above).

• prevalent [prev′ -l nt] widespread occurrence.

• prevention [pre-ven′sh n] in disease control terms includes measures designed to prevent the introduction of a disease into areas where it does not already exist, and improve the resistance of the population and reduce the chances of the infection spreading, when the disease already exists in the population.

• preventive [pre-ven′tiv] serving to avert the occurrence of; prophylactic.

  • veterinary p. medicine science aimed at preventing disease in animals. Preventive medicine has been a large part of general practices for many years and is currently expanding the sorts of services that it provides by the inclusion of such items as herd health programs, nutrition programs, biosecurity, cytogenetic surveillance, embryo transfer.
  • veterinary p. screening see screening test.
  • veterinary p. therapeutics the positive aspects of repair of nutritional deficiencies; the provision of therapeutic agents as part of a preventive medicine program. Daily administration of small doses of anthelmintics, treatment of the trypanosomiases are examples.

• prevertebral [pre-vur′t -br l] ventral to a vertebra.

• prevesical [pre-ves′ľ-k l] ventral to the bladder.

• previable [pre-vi′ -b l] before the time at which the fetus is capable of maintaining a separate existence.

  • p. period the period of fetal life just prior to the time at which the fetus is capable of being viable.

• Prevotella [pre″vo-tel′ ] a genus of gram-negative anaerobic bacteria in the family Prevotellaceae. Previously grouped in the genus Bacteroides. Involved in periodontal disease and a cause of dog and cat bite wound infections. P. oralis been isolated from meningitis in a dog.

  • P. melaninogenica isolated from footrot and foot abscesses of cattle. Previously called Bacteroides melaninogenicus.
  • P. ruminicola one of the predominant anaerobic gram-negative bacterial species in ruminal contents.

• preweaning [pre-wēn′ing] the period just before the young animal is weaned. This includes the neonatal period and is the period during which most deaths occur.

• prezygotic [pre-zi-got′ik] before a zygote is formed; occurring before completion of fertilization.

• priapism [pri′ -piz″ m] persistent abnormal erection of the penis in the absence of sexual stimulation, accompanied by pain and tenderness. It is seen in diseases and injuries of the spinal cord, and may be caused by vesical calculus and certain injuries to the penis.

• Pribnow box the sequence of five to 10 bases in the promotor region of Escherichia coli genes. It is a variant of a basic sequence TATAATG. Called also the Pribnow-Schaller box. See also TATA box.

  • Pricetrema zalophi a liver fluke found in fur seals in large numbers without causing apparent clinical illness.

• prick-eared [prik] in dogs, used to describe upright ears, usually with a pointed tip.

• pricket a male deer with his first set of horns at 2 years of age.

• prickly many sharp spines protrude.

  • p. black rolypoly Sclerolaenamuricata.
  • p. jack Emex australis.
  • p. paddymelon Cucumismyriocarpus.
  • p. pear Opuntia spp.
  • p. rolypoly Sclerolaenamuricata.

• prickly heat miliaria of humans; not a term used in veterinary dermatology.

• PRID progesterone releasing intravaginal device.

• pride of California Lathyrussplendens.

• prilocaine [pril′o-kān] a local anesthetic, used as the hydrochloride salt.

• primaquine an antiprotozoal agent used as the phosphate in the treatment of theileriosis, babesiosis, leishmaniasis, and trypanosomiasis.

• primary [pri′mar-e] first; basic.

  • p. accession the first contact with the veterinarian by an animal for the particular condition or disease incident that is the cause of the visit.
  • p. ruminant gastrointestinal dysfunction dysfunction intrinsic to the gastrointestinal tract of the ruminant; not secondary to dysfunction in some other organ.

• primase [pri′mās] a specialized RNA polymerase that synthesizes short stretches of RNA used as primers in DNA replication.

• primate [pri′māt] an animal belonging to the highest order of mammals, Primates, which includes humans and the nonhuman primates, the apes, monkeys, lemurs, tree-shrews, lorises, aye-ayes, pottos, bush babies, and tarsiers. They are characterized by being plantigrade, pentadactyl, by having clavicles, a complete dentition without specialized molars, a voluminous and complicated brain, and a supple hand with a thumb that can be approximated to any of the fingers. They have excellent sight and are highly adapted to an arboreal existence, including the possession by some of a prehensile tail.

  • catarrhine p. member of the parvorder Catarrhini (OldWorld monkeys).
  • platyrrhine p. member of the parvorder Platyrrhini (New World monkeys).

• prime first grade or best quality.

• primer [prīm′ r] oligonucleotide that is hydrogen-bonded to the template strand of DNA; required for the replication of DNA by polymerase.

  • random p. method a method of labeling DNA in vitro by use of short oligonucleotides (often hexanucleotides) with random sequence that anneal to and prime the denatured target DNA at multiple sites. Called also random-primed oligo-labeling.
  • p. walking an orderly method for sequencing DNA that involves obtaining some sequence, then making an oligonucleotide primer to the end of the sequence obtained and using it as a primer for the next sequencing reaction and repeating this until the whole sequence is determined.

• primidone [prim′ľ-dōn] an anticonvulsant related to phenobarbital. Primidone is metabolized to phenobarbitone by the liver, the activity of which accounts for 85% of its anticonvulsant effects. Used in dogs to control seizures although it has been reported to be more commonly associated with the development of hepatic failure than phenobarbital itself.

• primigravida [pri″mľ-grav′ľ-d ] an animal pregnant for the first time; gravida I.

• primipara [pri-mip′ -r] unipara; a female that has had one pregnancy that resulted in viable offspring, para I.

• primiparity [pri″mľ-par′ľ-te] the state of being a primipara.

• primitive [prim′ľ-tiv] first in point of time; existing in a simple or early form; showing little evolution.

• primordial [pri-mor′de- l] original or primitive; of the simplest and most undeveloped character.

  • p. germ cell cells that provide the origins of the spermatozoa and the ovum; they originate from the yolk sac endoderm and migrate to the developing gonad.

• primordium [pri-mor′de- m] the first beginnings of an organ or part in the developing embryo. Called also anlage.

• Prince’s plume see Stanleya pinnata.

• Prince of Wales feather Amaranthusreflexus.

• principle [prin′sľ-p l] 1. a chemical component. 2. a substance on which certain of the properties of a drug depend.

  • active p. any constituent of a drug that helps to confer upon it a medicinal property.

• print identifying mark left by part of an animal’s anatomy. The print left by the nasolabial or nasal plane is used for identification. See also nasolabiogram.

• prion [pri′on, pre′on] a small protein that infects cells causing itself to be replicated resulting in the accumulation, in the central nervous system and other tissues, of a protease-resistant, disease-associated isoform of the prion protein (called PrPSc). There are a number of prion diseases or transmissible spongiform encephalopathies (TSEs), and all are fatal protein-misfolding neurodegenerative diseases. All TSEs share pathologic features, and most have infectious mechanisms, but they also have distinct differences in transmission and epidemiology due to host factors and strain differences encoded within the structure of the misfolded prion protein. Prions can be detected in tissues by infective bioassay, animal inoculation, or by Western blot or immunochemistry. Prions cause spongiform encephalopathies of humans and animals, such as Creutzfeldt–Jakob disease (CJD), kuru, scrapie, transmissible mink encephalopathy, feline spongiform encephalopathy, and bovine spongiform encephalopathy.

• prism needle [priz′ m] has a prism-like or triangular head used for drawing blood.

• pritchel a metal tool used to punch nail holes in horseshoes.

• privet see Ligustrum.

• privileged information that is legally protected from being made public, available only to those having special rights or advantages.

  • p. information information about a client’s animals or business to which the veterinarian has access because of his/her professional activities; it is a convention that such information is regarded as confidential.
  • p. sites areas of the body that escape immune surveillance, e.g., cornea.

• prn as required; used in medical records.

• p.r.n. [L.] pro re nata (according to circumstances). Abbreviation used in medical records and nursing notes.

• Pro proline.

• pro- word element. [L., Gr.] before, in front of, favoring.

• pro-climax [pro″kli′maks] in ecological terms the stage reached in an ecosystem when humans intervene to prevent the natural climax or balance in the ecosystem from developing, e.g., vaccination of a large part of a canine population against distemper achieves a different climax serologically than the natural climax achieved by allowing the disease to develop unrestrained.

• pro-drug a compound that, on administration, must undergo chemical conversion by metabolic processes before becoming an active pharmacological agent; a precursor of a drug.

• pro-oestrus [pro-es′tr s] see proestrus.

• pro re nata (p.r.n.) [L.] according to circumstances.

• pro-time see prothrombin time test.

• proaccelerin [pro″ak-sel′ r-in] clotting factor V.

• proacrosomal granules [pro″ak-ro-so′m l] precursors of the acrosomal vesicle in the Golgi complex of the spermatid.

• proactinomyces see Actinomyces.

• proactivator [pro-ak′tľ-va″t r] a precursor of an activator; a factor that reacts with an enzyme to form an activator.

• proatlas [pro-at′l s] a rudimentary vertebra that in some animals lies cranial to the atlas; sometimes seen as an anomaly.

• probability [prob″ -bil′ľ-te] the basis of statistics. The relative frequency of occurrence of a specific event as the outcome of an experiment when the experiment is conducted randomly on very many occasions. The probability of the event occurring is the number of times it did occur divided by the number of times that it could have occurred. Defined as:

  p = x(x + y)

  where p=probability, x=positive outcomes, y=negative outcomes.

  • conditional p. the probability that event A occurs, given that event B has occurred. Written P(AB).
  • prior p. estimation of the probability that a particular phenomenon or character will appear before putting the patient to the test, e.g., testing the probable productivity of a patient by testing its forebears.
  • subjective p. the measure of the assessor’s belief in the probability of a proposition being correct.

• proband [pro′band] propositus.

• probang [pro′bang] a flexible rod with a ball, tuft, or sponge at the end; used to apply medications to or remove matter or biopsy from the esophagus, pharynx, or larynx. Instruments used in large animals consist of flexible tubes containing a flexible stilette.

  • p. gag a wooden rod that is placed across the mouth in cattle, and jammed between the molars and above the tongue. It has a hole transfixing its center through which the probang is passed.

• probatocephaly [pro-bat-o-sef′ -le] an inherited, congenital deformity of the head in a calf giving the appearance of a sheep head. Called also sheepshead.

• probe [prōb] 1. a long, slender instrument for exploring wounds or body cavities or passages. 2. a labeled (e.g., with a radioactive isotope or an enzyme) DNA molecule used in hybridization to detect DNA homologous to the fragment.

  • cryosurgical p. see cryoprobe.
  • electroejaculation p. a probe containing electrodes that is inserted in the rectum of the male animal and connected to an electrical power source to stimulate the nerves controlling emission and ejaculation of the semen.
  • freezing p. see cryosurgery.

• probenecid [pro-ben′ -sid] a human drug used to promote excretion of uric acid in the treatment of gout in humans; also used in snakes. Competitively inhibits tubular excretion of penicillins; used with certain antibiotics such as penicillin G and ampicillin to prolong their plasma half-life.

• probiotic [pro″bi-ot′ik] defined by the World Health Organization (WHO) as “… living microorganisms, which when administered in adequate amounts, confer a health benefit on the host.” A form of complementary or alternative medicine, the organisms typically include Lactobacilli, Bifidobacteria, and enterococci, which when administered orally are believed to be act by excluding or reducing the growth of potential pathogenic bacteria by competitive inhibition and production of inhibitory substances. Used in dogs and cats in the treatment and prevention of diarrhea and as growth promoters in livestock. See also prebiotic.

• problem a question to which there is no obvious, immediate answer; a question that requires some work done on it before a solution can be available.

  • p. knowledge coupler system computer-assisted diagnosis system designed for use in human medicine; based on a special matching algorithm known as pattern recognition.
  • p. list the list of problems to be overcome in a particular patient; in hospitals using a problem-oriented case management system.
  • p. name a generally accepted, preferred name for a clinical sign, syndrome or other indicant such as a positive laboratory test, poor work or production performance or poor reproductive result.
  • p.-oriented case management a system of managing patients based on the recognition of the patient’s problems as targets for correction, planning the treatment program to achieve that, and assessing performance in terms of results with each of the problems and with the case overall. It is an excellent teaching procedure but is also helpful in maintaining the correct perspective in the patient’s program.
  • p.-oriented diagnosis a system of diagnosis that starts off with the cardinal sign presented by the patient and proceeds in steps to identify the body system involved, the part of the system affected, the nature of the lesion and the cause of the lesion.
  • p.-oriented medical record see problem-oriented medical record.
  • p. solving the basis of clinical veterinary (and most other) education; learning diagnosis by practicing resolving clinical problems—the essential problem being ‘which disease is most likely to be the cause of the syndrome presented by this patient’.

• proboscis [pro-bos′kis] elongated, flexible feeding apparatus, formed of the fused mouthparts, in some insects; the eversible hooked attachment organ of acanthocephalans.

• Probstmayria a genus of roundworms in the family Kathlaniidae.

  • P. vivipara a minute worm found in the colon of horses, often in enormous numbers but without apparent pathogenic effect.

• procainamide [pro-kān′ -mīd] a class 1a antiarrhythmic agent, similar to quinidine, used as the hydrochloride salt in the treatment of cardiac arrhythmias.

• procaine [pro′kān] a local anesthetic; the hydrochloride salt is used in solution for infiltration, nerve block and spinal anesthesia.

  • p. penicillin see penicillin G.

• Procambarus clarkii farmed crustacean; called also red swamp crayfish or crawfish; Louisiana crayfish or crawfish.

• procarbazine [pro-kahr′b -zēn] an antineoplastic agent that acts by inhibiting the synthesis of DNA, RNA, and protein. Used in the MOPP protocol.

• procarboxypeptidase [pro″kahr-bok″se-pep′tľ-dās] the inactive precursor (zymogen) of carboxypeptidase, which is converted to the active enzyme by the action of trypsin.

• procarcinogen [pro″kahr-sin′ -j n] a chemical substance that becomes carcinogenic only after it is altered by metabolic processes.

• procaryote [pro-kar′e-ōt] prokaryote.

• procentriole [pro-sen′tre-ōl] the immediate precursor of centrioles and ciliary basal bodies.

• procercoid [pro-sur′koid] the first larval stage in the life cycle of a bothriocephalidean or diphyllobothriidean (=pseudophyllidean) cestode, e.g., Spirocerca erinacei. The procercoid is a solid bodied stage with oncospheral hooks carried on the cercomer in the posterior region.

• process [pros′es; pro′ses] 1. a prominence or projection, as from a bone. 2. a series of operations or events leading to achievement of a specific result; also, to subject to such a series to produce desired changes.

  • accessory vertebral p. a process that protrudes caudally from the vertebral arch of the thoracic and lumbar vertebrae between the transverse and caudal articular processes that overlaps the succeeding vertebra in dogs and some other species. Called also processus accessorius.
  • acromial p. acromion.
  • alveolar p. see alveolar¹ process.
  • articular p. one of the pair of processes at each end of a typical vertebrae born on the vertebral arch that articulates with a complementary articular process of an adjacent vertebra. Called also processus articularis cranialis, processus articularis caudalis.
  • arytenoid cartilage corniculate p. a horn-like process that extends dorsomedially and forms one side of the caudal margin of the entrance to the larynx.
  • basihyoid lingual p. a median process that projects rostrally from the basihyoid bone into the root of the tongue in the horse and cow.
  • basilar p. the basilar part of the occipital bone projecting rostrally from the foramen magnum.
  • caudate p. the elongated right projection of the two processes on the visceral surface of the caudate lobe of the liver.
  • clinoid p. any of the two paired (anterior and posterior) processes of the sphenoid bone; they suspend the diaphragma sellae (like a four-poster bed) that partially separates the underlying pituitary from the brain above. (The human skull occasionally has, in addition, a pair of medial clinoid processes—small elevations on the floor of the hypophyseal fossa.) condylar p. the articular surface of the mandible with which the lower jaw articulates with the temporal bone at the temporomandibular joint; it consists of a head (caput mandibulae) born on a neck (collum mandibulae).
  • distal phalangeal extensor p. the process on the dorsal border of the distal phalanx to which the common digital extensor tendon is attached. Called also processus extensorius.
  • ethmoid p. a bony projection above and behind the maxillary process of the inferior nasal concha of some species.
  • frontal p. 1. of the zygomatic bone; the part of the zygomatic bone that extends upward to contribute to the lateral margin of the orbit and that forms a suture with the zygomatic process of the frontal bone (sutura frontozygomatica); conspicuous in species with a postorbital bar, such as most ungulates. 2. a cone-shaped mass of red vascular tissue that lies across the base of the turkey’s beak. Called also snood, nasal comb.
  • frontal bone cornual p. the bony core of the horn that projects from the frontal bone; the process is usually pneumatic because the frontal sinus extends into it.
  • frontonasal p. an expansive facial process in the embryo that develops into the forehead and upper part of the nose.
  • lateral nasal p. a process that borders the nasal pit, eventually the nostril, and that is derived from the embryo’s frontonasal mesenchyme.
  • malar p. see zygomatic process of the maxilla (below).
  • mammillary p. a conspicuous quadrilateral tubercle between the transverse and cranial articular processes on the thoracic and lumbar vertebrae. Most conspicuous in carnivores.
  • mandibular angular p. a process that protrudes from the ventral caudal angle of the mandible and is conspicuous in carnivores and acts as the attachment for the digastric muscle.
  • mastoid p. a conical projection at the base of mastoid portion of temporal bone.
  • medial nasal p. one of the frontal processes derived from frontonasal mesenchyme and forming part of the border of the nasal pits, the future nostrils.
  • odontoid p. a toothlike cranial projection of the axis that articulates with the atlas and that is the embryologic homologue of the body of the atlas. See also dens.
  • palatine p. medial and lateral palatine processes contribute to the development of the palate and the separation of the oral and nasal cavities.
  • paracondylar p. a prominent process lateral to the occipital condyle at the caudal extremity of the skull.
  • pterygoid p. one of the wing-shaped processes of the sphenoid bone.
  • retroarticular p. a flange of bone that protrudes ventrally from the caudal end of the zygomatic arch; it carries part of the articular surface of the temporomandibular joint on its rostral edge.
  • spinous p. of vertebra a dorsal median process of a vertebra giving attachment to muscles of the back.
  • suprahamate p. a flat, caudally directed process on the acromion of the scapular spine of cats and some other species.
  • tail vertebral hemal p. paired ventral processes of the more cranial tail vertebrae; the coccygeal vessels run between them.
  • uncinate p. any hook-like process, such as occurs on the cervical vertebrae of some animals, on the lacrimal bone, or on the pancreas of cattle.
  • urethral p. an extension of the urethra beyond the end of the glans penis in several species. In the horse it is buried in a deep recess (fossa glandis). in the small ruminants it is a thin, loose, wormlike appendage.
  • xiphoid p. the caudal sternebra, consisting of a rod of bone that typically supports a xiphoid cartilage. Called also xiphoid, ensiform.

• processing [pros′es-ing] exposure to a set of processes.

  • digital image p. see digital image processing.
  • feed p. includes mechanical (crushing, crimping) thermal (boiling, exploding), chemical (acid or alkali treatment), and combinations of these.
  • feedlot p. procedures conducted shortly after introduction of cattle to feedyards that include tagging or branding, deworming, and delousing, vaccination and implantation with growth promotants, and examination and treatment of any sick animals.
  • meat p. meat being exposed to any one of a series of curing or preserving processes such as salting, wet pickling, drying, cooking and canning, sausage manufacture, ham curing.
  • x-ray film p. developing and fixing an exposed x-ray film. May be performed manually using tanks of chemicals or using automatic machines at higher temperatures to give shorter processing times and requiring less labor.

• processus [pro-ses′ s] pl. processus [L.] process.

• prochlorperazine [pro″klor-per′ -zēn] a phenothiazine derivative; used as a tranquilizer and antiemetic.

• prochondral [pro-kon′dr l] occurring before the formation of cartilage in embryological development.

• procidentia [pro″sľ-den′sh ] a state of prolapse, especially prolapse of the uterus.

• procoagulant [pro″ko-ag′u-l nt] 1. tending to promote coagulation. 2. a precursor of a natural substance necessary to coagulation of the blood.

• procoelous having the cranial surface concave; said of certain vertebrae such as on the centrum of cervical vertebrae of horses and cattle.

• procollagen [pro-kol′ -j n] the precursor of collagen, synthesized in osteoblasts and fibroblasts and subsequently converted to form collagen by procollagen peptidase.

  • p. N-peptidase one of the enzymes involved in the conversion of procollagen to collagen. There is inadequate activity of this enzyme in osteogenesis imperfecta, dermatosparaxis.

• proconvertin [pro″k n-vur′tin] clotting factor VII. Also known as stable factor.

  • p. deficiency an autosomal recessive trait that occurs in Beagles, Airedales, Alaskan malamutes, giant Schnauzers, Scottish deerhounds, and cats, and causes mild to moderate bleeding. Affected dogs may show mild bleeding and/or easy bruising. A DNA test is available. Called also hypoproconvertinemia.

• procreation [pro″kre-a′sh n] the act of begetting or generating.

• proctatresia [prok″t -tre′zh] imperforate anus.

• proctectasia [prok″tek-ta′zh ] dilatation of the rectum or anus.

• proctectomy [prok-tek′t -me] excision of the rectum.

• proctitis [prok-ti′tis] inflammation of the rectum.

  • ulcerative p. an early stage in the development of rectal stricture in pigs. See also rectal stricture.

• proct(o)- word element. [Gr.] relationship to the rectum; see also words beginning rect(o)-.

• proctocele [prok′to-sēl] hernial protrusion of part of the rectum into the vagina; rectocele.

• proctoclysis [prok-tok′li-s s] slow introduction of large quantities of liquid into the rectum.

• proctocolonoscopy [prok″to-ko″l n-os′k -pe] endoscopic examination of the lumen of the rectum and distal colon.

• proctocystotomy [prok″to-sis-tot′ -me] removal of a bladder calculus through the rectum.

• proctodeum [prok″to-de′ m] 1. the ectodermal depression of the caudal end of the embryo, which becomes the anal canal; called also anal pit. 2. the smallest compartment of the avian cloaca. It contains the bursa of Fabricius.

• proctolitis [prok″to-li′tis] proctitis.

• proctology [prok-tol′ -je] the study of disorders of the rectum and anus.

• proctoparalysis [prok″to-p -ral′ľ-sis] paralysis of the anal and rectal muscles; proctoplegia.

• proctopexy [prok′to-pek″se] fixation of the rectum to adjacent tissue.

• proctoplasty [prok′to-plas″te] plastic repair of the rectum and anus.

• proctoplegia [prok″to-ple′j ] proctoparalysis.

• proctoptosis [prok″top-to′sis, prok″to-to′sis] prolapse of the rectum.

• proctorrhaphy [prok-tor′ -fe] suture of the rectum.

• proctorrhea [prok″to-re′ ] a mucous discharge from the anus.

• proctoscope [prok′to-skōp] a speculum or tubular instrument with illumination, inserted through the anus, for examining the lumen of the rectum.

• proctoscopy [prok-tos′k -pe] endoscopic examination of the lumen of the rectum.

• proctospasm [prok′to-spaz″ m] spasm of the rectum.

• proctostenosis [prok″to-st -no′sis] stricture of the rectum.

• proctostomy [prok-tos′t -me] surgical creation of a permanent artificial opening from the body surface into the rectum.

• proctotomy [prok-tot′ -me] incision of the rectum, usually for anal or rectal stricture.

• proctovalvotomy [prok″to-val-vot′ -me] incision of the rectal valves.

• procumbent [pro-kum′b nt] prone; lying on the abdomen. Called also ventral recumbency.

• procyonid a member of the canid family Procyonidae.

• Procyonidae a family of animals comprising the ring-tailed cat, cacomistle, raccoon, coati, kinkajou, olingo.

• prod a prod to make animals move or move faster. Ranges from a pointed stick to an electric instrument. The electrically powered units may be battery-powered or operate off mains power, most suited to use in a fixed location such as an abattoir, or a portable model with a small generator that is operated by opening and clenching the hand. Invaluable when loading or encouraging downer animals to rise but are brutalizing and cruel if used unnecessarily.

• prodromal [pro-dro′m l] the stage of premonitory signs presaging the onset of disease or of specific clinical signs such as seizures.

• prodrome [pro′drōm] a premonitory clinical sign; a clinical sign indicating the onset of a disease.

• product endorsement [prod′ kt] a public statement declaring the virtues and recommending the use of a product. Discouraged by codes of veterinary ethics other than by the publication of research results.

• production [pro-duk′sh n] 1. the act of producing. 2. the total of things produced.

  • animal p. see animal production.
  • p. diseases diseases caused by systems of management, especially feeding and the breeding of high-producing strains of animals and birds, in which production exceeds dietary and thermal input. Includes the group of diseases known in veterinary literature as ‘metabolic diseases’. They differ from nutritional deficiencies in which it is the nutritional supply that falls short of normal production.
  • p. efficiency the efficiency of conversion of feedstuffs to animal product. The basis of the cost-efficiency of any animal production undertaking.
  • p. function the relationship between the input of a single variable and the output of the product.
  • p. indices specific indices such as live pigs produced per sow per year, intercalving interval, rate of gain of body weight per day in beef cattle, used as benchmarks of productivity.
  • p. ketosis ketosis as a production disease, one which is produced by animal management; failure of the dietary input to satisfy the demands of the energy output in milk.
  • p. losses product that is produced but not harvested or sold, e.g., mastitic milk from cows with mastitis.
  • p. medicine see production diseases (above).
  • p. program a schedule of activities relating to feeding, breeding, and health maintenance aimed at maximizing the profitability of an animal enterprise. Includes the establishment of targets of production in the areas of specific indices of productivity and the monitoring of production. The programs may be computerized so that the entry of data is simplified and analysis of the data automatic and regularly periodic. The establishment of programs and their maintenance by way of modification of practices and strategies to match changes of production efficiency require the participation of species specialists. See also management factors.

• productive [pro-duk′tiv] producing or forming. Said especially of (1) an inflammation that produces new tissue or of a cough that brings forth sputum or mucus, and (2) an animal or animal enterprise that has a net excess production that is available to the farmer and produced in a costeffective operation.

  • p. life that part of an animal’s life during which it is productive.

• productivity the amount or quality or value of the output of a food animal. Best measured in terms of the percentage productivity compared with a target based on productivity of peers. It is customary nowadays to state productivity in terms of return on capital invested, or per head of livestock or per acre or per unit of workforce, and may be for a period, e.g., annual, lifetime, or for a specific unit, e.g., farm, the dairy herd on a mixed farm.

  • p. index includes such items as wool yield per hectare, wins per race starts.
  • p. marginal value see marginal revenue.

• proelastase [pro″e-las′tās] the inactive (zymogen) precursor of elastase, secreted by the pancreas and activated by trypsin in the small intestine.

• proencephalus [pro″ n-sef′-l s] a fetus with a protrusion of the brain through a frontal fissure.

• proenzyme [pro-en′zīm] zymogen; an inactive precursor of an enzyme.

• proerythroblast [pro″ -rith′ro-blast] the earliest erythrocyte precursor. A large round cell with a large nucleus and small amount of deeply basophilic staining cytoplasm. Called also pronormoblast, rubriblast.

• proestrogen [pro-es′tro-j n] a substance without estrogenic activity but which is metabolized in the body to active estrogen.

• proestrus [pro-es′tr s] the period of heightened follicular activity preceding estrus.

• profession [pro-fe′sh n] a calling or vocation requiring specialized knowledge, methods, and skills, as well as preparation in an institution of higher learning, in the scholarly, scientific, and historical principles underlying such methods and skills. A profession continuously enlarges its body of knowledge, functions autonomously in formulation of policy, and maintains by force of organization or concerted opinion high standards of achievement and conduct. Specifically in this regard it maintains and polices a code of ethics and conducts a professional organization of which a large majority of the profession are members. Members of a profession are committed to continuing study, placing service above personal gain, and are committed to providing practical services vital to human and social welfare.

• professional [pro-fesh′ -n l] 1. pertaining to one’s profession or occupation. 2. one whose income is derived from the practice of his/her profession.

• professionalism [pro-fesh′ -nl-iz- m] the upholding by individuals of the principles, laws, ethics, and conventions of their profession.

• profilaggrin a structural protein synthesized by cells of the stratum granulosum and a precursor of filaggrin.

• profile [pro′fīl] a simple outline, as of the side view of the body or head; by extension, a graph representing quantitatively a set of characteristics determined by tests. In animals the same purpose may be served by photographing it against a grid background. Profiles are used to determine an animal’s conformational similarity to a standard set by a breed society and, especially in ruminants, as an aid to the diagnosis of diseases of the abdomen.

  • biochemical p. a panel of tests, usually selected for their ability in the particular species to evaluate the functional capacity of several critical organ systems and general health, but sometimes customized to particular clinical presentations, such as liver profile, renal profile, geriatric profile and others. The ‘profile’ may literally be the results plotted on individual, parallel numerical scales, producing a pattern similar to a bar graph.
  • cost–benefit p. a written or graphic description of the costs and production returns of an animal enterprise, set out according to a set of standard indices and parameters so that inter-herd comparisons are facilitated. A standard feature in modern animal health and production programs.

• Profilicollis minutus see Polymorphus boschadis.

• profilometer [pro″fīl-om′ -t r] a device for measuring the shape of a facial profile and expressing the results mathematically. Such an instrument was used extensively at one time as a means of detecting the heterozygotes for inherited achondroplastic dwarfism.

• profilometry [pro″fīl-om′ -tre] a system for studying disorders of micturition using electromyography and measurement of intraurethral pressures. See also urethral pressure profile.

• profit the amount by which income exceeds expenditure.

  • p. sharing profit sharing between a professional and a lay person is illegal in most countries because it is considered to be improper for a nonveterinarian to have any authority over the quality and style of the work of a professional person. in the US, the legality of a lay person to own a veterinary practice varies between states.

• proflavine a constituent of acriflavine, C₁₃H₁₁N₃, used as a topical, and previously as a urinary, antiseptic in the form of the hemisulfate salt.

• proctocolpoplasty [prok″to-sis′to-plas″te] repair of a rectovaginal fistula.

• profundus [pro-fun′d s] [L.] deep.

• Progamotaenia anoplocephalid cestodes found in the bile ducts and intestines of kangaroos, wallabies, wombats.

• progastrin [pro-gas′trin] an inactive precursor of gastrin.

• progenesis [pro-jen′ľ-s s] the maturation of gametes within an organism before it has reached physical and sexual maturity.

• progenitor [pro-jen′ľ-t r] ancestor, including parent.

  • p. cell a biological cell with a tendency to differentiate into a specific type of cell, but is already more specific than a stem cell and is pushed to differentiate into its ‘target’ cell; see stem cell.

• progeny [proj′ -ne] offspring; descendants.

  • expected p. difference (EPD) the difference in performance to be expected from future progeny of a sire, compared with that expected from future progeny of the average sire in the same population. EPDs are generally expressed either as a plus or minus difference from the population average, reported in the units of measure of the trait. Incorporates adjustment for environmental and management group effects and genetic trend.
  • p. testing the evaluation of the value of an individual’s genotype using the performance records of it’s progeny.

• progestagens [pro-jes′t -j ns] progestogens

• progestational [pro″j s-ta′shn- l] preceding gestation; referring to changes in the endometrium preparatory to implantation of the developing ovum should fertilization occur.

  • p. agent (hormone) a group of hormones secreted by the corpus luteum and placenta and, in small amounts, by the adrenal cortex, including progesterone, Δ⁴-3-ketopregnen-20(α)-ol, and Δ⁴-3-ketopregnene-20(β)-ol; agents having progestational activity are also produced synthetically.

• progesterone [pro-jes′t -rōn] a steroid sex hormone that is the principal progestational hormone. Used therapeutically in the treatment of threatened abortion in some species, in estrus control in dogs, cats, and horses, and occasionally in treatment of some types of skin diseases. During the maturation of the ovum, estrogen, the principal female sex hormone, is produced at a high rate. At ovulation estrogen production is sharply reduced, and the follicle is replaced by the corpus luteum of which the main function is to produce progesterone. Unless fertilization takes place, the corpus luteum regresses. The progesterone produced by the corpus luteum is promptly carried by the blood to the uterus, as was the estrogen that preceded it. Both hormones now work to prepare the uterus for possible conception. In pregnancy, progesterone acts in a way that protects the embryo and fosters growth of the placenta. By decreasing the frequency of uterine contractions it helps to prevent expulsion of the implanted ovum. It also promotes secretory changes in the mucosa of the uterine tubes, thereby helping to provide nutrition for the fertilized ovum as it travels through the tube on its way to the uterus. Another function of progesterone is promotion of the development of the mammary glands in preparation for lactation. Prolactin, from the anterior lobe of the pituitary gland, stimulates production of the milk, and progesterone prepares the glands for secretion.

  • p. assay the estimation of progesterone in milk or blood is used as a pregnancy test.
  • blood p. the concentration of progesterone in the blood (progesteronemia); used as a means of early pregnancy diagnosis in cows and ewes. See also progesterone, pregnancy tests.
  • p.-induced lactation see lactation induction.
  • p. milk test assay of progesterone in milk used as a pregnancy test.
  • p. plasma test the original pregnancy test that survives as the milk progesterone test; used in dogs as a guide in predicting the time of ovulation.
  • p. releasing intravaginal device (PRID) used as a means of synchronizing estrus in cows and sheep as an aid to structured artificial insemination programs.

• progestin [pro-jes′tin] originally, the crude hormone of the corpus luteum; it has since been isolated in pure form and is now known as progesterone. Certain synthetic and natural progestational agents are called progestins.

• progestogen [pro-jes′to-j n] hormones with progesterone-like activity. Called also progestagens, progestins, gestagens.

• proglossis [pro-glos′is] the tip of the tongue.

• proglottid, proglottis [pro-glot′id] one of the segments making up the strobila of a tapeworm.

• prognathism, prognathia, prognathous [prog′n -thiz- m] abnormal protrusion of one or both jaws.

• prognose [prog-nōs′] to give a prognosis.

• prognosis [prog-no′sis] a forecast of the probable course and outcome of disease and the prospects of recovery as indicated by the nature of the disease and the clinical signs of the case.

• progoitrin an antithyroid substance in the seeds, and to a lesser extent the foliage, of rape and other plants in the family Brassicae. It is a glycoside that is converted to an active oxazolidone by an enzyme also resident in the plant. This substance 1,5-vinyl-2-thiooxazolidone is goitrogenic and inhibits growth.

• program, programme a planned course of action, e.g., herd health program, production program.

  • linear p. a management program used to determine the best mix of ingredients or services to be used in a particular situation to maintain the highest level of productivity or profitability or other similar parameter.
  • public p. a disease control program available to all members of the public, e.g., rabies control, tuberculosis eradication.
  • whole farm p. one that takes into account all of the enterprises on a farm and presents a financial accounting of the farm as a whole.

• Program for the Assessment of Veterinary Education Equivalence (PAVE) see American Association of Veterinary State Boards.

• programmed cell death see apoptosis.

• progranulocyte [pro-gran′u-lo-sīt″] promyelocyte.

• progravid [pro-grav′id] denoting the phase of the endometrium in which it is prepared for pregnancy.

• progress notes narrative records kept on changes in the animal’s condition and treatment administered. In the problem-oriented medical record, it is written in the SOAP format.

• progressive [pro-gres′iv] advancing, increasing in scope and severity.

  • p. interstitial pneumonia in sheep see maedi.
  • porcine congenital p. ataxia and spastic paresis inherited autosomal recessive disease of swine manifest shortly after birth as a severe lethal neuropathy.

• prohemistomiasis [pro-he-mis′to-mi′ -sis] disease caused by intestinal infection with the Cyathocotylid trematode Prohemistomum vivax; occurs in humans, dogs, and cats in Egypt and Israel.

• Prohemistomum vivax a digenetic trematode found in the intestines of cats and dogs in North America. Metacercariae occur in catfish.

• prohormone [pro-hor′mōn] a precursor of a hormone, such as a polypeptide that is cleaved to form a shorter polypeptide hormone, or a steroid that is converted to an active hormone by metabolism.

• proinsulin [pro-in′su-lin] a precursor of insulin, having low biological activity.

• projection [pro-jek′sh n] throwing forward.

  • central p. law the laws of physics applied to the primary x-ray beam of photons, e.g., the closer the object being x-rayed is to the image receptor the sharper will be its definition.
  • radiographic p. the name of a radiograph describing direction the x-ray beam passed through the patient. For example, for a ventrodorsal projection of the thorax, the x-ray beam passes from ventrally to dorsally through the patient.
  • somatotopical p. an arrangement by which a picture of the body is represented on a surface, such as arrangement of the neurons on the surface of cerebral cortex in the same layout as the topography of the body from which the efferent nerve impulses depart or to which afferent impulses come.

• prokaryocyte [pro-kar′e-ō-sīt] prokaryote.

• prokaryon [pro″kar′e-on] 1. nuclear material scattered in the cytoplasm of the cell, rather than bounded by a nuclear membrane; found in some unicellular organisms, such as bacteria. 2. prokaryote.

• prokaryote [pro-kar′e-ōt] a single-celled organism lacking a true nucleus and nuclear membrane, as well as other membrane-bound organelles.

• prokinetic [pro″kľ-net′iks] a drug that enhances gastrointestinal motility, and thus the passage of digesta through the gastrointestinal tract, by increasing the frequency and/or intensity of peristaltic contractions.

• prolactin [pro-lak′tin] a hormone secreted by the anterior pituitary that promotes the growth of mammary tissue and stimulates and sustains milk production in postpartum mammals, and shows luteotropic activity in certain mammals. Promotes the secretion of milk in the crop of pigeons and doves. Called also lactogenic hormone, luteotropic hormone, LTH, and mammotropin. It is identical with luteotropin.

  • p. inhibitory factor (PIF) probably the catecholamine dopamine, released in the hypothalamus, carried to the anterior pituitary via the hypophysial portal system, and inhibits the secretion of prolactin.
  • p. releasing factor (PRF) appears to be released from the hypothalamus in a pulsatile fashion, and it is the fluctuation in PRF that regulates the circulating concentration of prolactin.

• prolamine a globular protein, e.g., zein in corn grain.

• prolan an outdated name for chorionic gonadotropin, LH, and FSH. Thought originally to be the hormone responsible for the uterine enlargement seen in the Ascheim–Zondek test.

• prolapse [pro-laps′] 1. literally the falling down, or downward displacement, of a part or viscus. In many instances in animals, the prolapse is lateral or even dorsal, e.g., in intervertebral disc prolapse. 2. to undergo such displacement.

  • anal p. the protrusion of a small amount of mucosa through the anus. Seen especially in puppies and kittens.
  • cloacal p. occurs in companion birds due to straining caused by endoparasitism, abdominal tumors, egg laying, and displaced sexual behavior, typically directed to human companions. Also occurs in reptiles.
  • fat p. see perivaginal fat prolapse.
  • ocular p. anterior displacement of the globe from the orbit; proptosis.
  • oviduct p. a minor prolapse of oviductal mucosa may stimulate cannibalism in others and the entire oviduct be removed via the cloaca.
  • parturient bladder p. may follow rupture of the floor of the vagina during parturition in the mare; it can protrude from the vulva.

    P-77.

    

    Prolapsed uterus, following prolonged dystocia in a mare

    P-78a.

    

    Vaginal fold prolapse in a bitch

  • perivaginal fat p. during a difficult parturition in a fat cow or heifer perivaginal fat is pushed caudally and bursts through the vaginal wall into the vagina.
  • preputial p. see preputial eversion.
  • penile p. inability to withdraw the penis into the prepuce, other than a paraphimosis. Not to be confused with phimosis; paralysis does occur in disease of the spinal cord, e.g., in some cases of rabies.
  • rectal p., p. of rectum protrusion through the anus of the mucosa only or the complete wall of the rectum. Uncommon in most species but commonplace in the pig because of anatomical weakness in the area, especially in some breeds. The feeding of estrogens exacerbates the tendency as may the occurrence of diarrheal disease.
  • p. retainer 1. a frame made of strong wire or thin metal rod and shaped like a lattice with obvious apertures for defecation and urination; strapped to the rear end of the cow so that the perineum will not bulge when the animal strains. 2. a bottle-shaped appliance sewn in to the vagina to prevent prolapse of the vagina.
  • third eyelid gland p. see cherry eye.
  • urethral p. protrusion of urethral mucosa at the end of the penis. Occurs in male dogs, especially English bulldogs.
  • urinary bladder–vaginal prolapse occurs occasionally in the cow as a complication of vaginal prolapse. The bladder is retrodeviated, and the urethra kinked so that urine flow is obstructed.
  • uterine p. displacement of the uterus so that the cervix is within the vaginal orifice (first-degree prolapse), the cervix is outside the orifice (second-degree prolapse), or the entire uterus is outside the orifice (third-degree prolapse). May be related causally to hypocalcemia in cattle.

    P-78b.

    

    Vaginal prolapse in a cow

  • vaginal p. 1. in bitches, edematous swelling of vaginal tissue during estrus occasionally results in a protrusion of vaginal mucosa, usually from the ventral vaginal wall but occasionally the entire circumference, at the vulval opening, where it may be subject to licking and abrasion until it regresses with the conclusion of estrus. Uncommonly, the urethral opening may be compromised. Properly referred to as a prolapse of vaginal mucosa or vaginal fold prolapse, but frequently and incorrectly called vaginal prolapse or vaginal hypertrophy. Called also estral eversion. 2. in cattle, goats, sheep, and rarely bitches, prolapse of the vaginal wall may also contain the urinary bladder or the cervix. Usually occurs during or shortly after parturition.

• prolapsus [pro-lap′s s] [L.] prolapse.

• prolepsis [pro-lep′sis] recurrence of a paroxysm before the expected time.

• prolidase [pro′lľ-dās] an enzyme that catalyzes the hydrolysis of the imide bond between the amino acids in any dipeptide with proline or hydroxyproline in the C-terminal position. Called also proline dipeptidase.

• proliferation [pro-lif″ -ra′sh n] the reproduction or multiplication of similar forms, especially of cells.

• proliferative [pro-lif′ r- -tiv] pertaining to or emanating from proliferation.

  • p. dermatitis see strawberry footrot.
  • p. bowel disease a disease of young ferrets caused by Lawsonia intracellularis and characterized by gross thickening of the small intestine and colon. There is acute or chronic diarrhea, weight loss, and sometimes neurologic signs of ataxia and muscle tremors. Similar to porcine proliferative enteropathy.
  • equine p. enteropathy see equine proliferative enteropathy.
  • p. exudative pneumonia of lambs see enzootic pneumonia.
  • p. hemorrhagic enteropathy see porcine proliferative enteropathy.
  • p. ileitis see porcine proliferative enteropathy.
  • p. interstitial pneumonia see enzootic pneumonia.
  • p. kidney disease important disease of salmonids; caused by the myxozoan Tetracapsuloides bryosalmonae.
  • p. optic neuropathy see equine proliferative optic neuropathy.
  • p. phase in uterine activity; called also follicular phase (of estrous or menstrual cycle). The lining epithelium of the uterus hypertrophies and becomes congested and edematous.
  • porcine p. enteropathy see porcine proliferative enteropathy.
  • p. urethritis see granulomatous urethritis.

• proligerous producing offspring.

• proligestone a long-acting progestin used in estrus control in bitches.

• prolinase [pro′lľ-nās] an enzyme that catalyzes the hydrolysis of dipeptides containing proline or hydroxyproline as N-terminal groups. Called also prolyl dipeptidase.

• proline (Pro) part of headword. [pro′lēn] a cyclic amino acid occurring in proteins; it is a major constituent of collagen.

• prolonged gestation may be inherited, caused by plant toxins or occur sporadically. Commonly, there is absence or developmental abnormality of the fetal adrenal or pituitary glands.

  • inherited p. g. occurs in several forms in cattle. Pregnancy is prolonged for 3 weeks to 3 months; in one form, the fetus is normal except that it is of very great size and can only be delivered by cesarean section. In another, the fetus does not develop beyond the 6-month stage and is a cyclops monster with only one eye. In a third, there are multiple skeletal deformities and cleft palate.
  • phytogenous p. g. poisoning by Veratrum californicum or Salsola tuberculata, fescue ergot alkaloids, some Brassica spp. cause prolonged gestation.

• prolotherapy a form of regenerative injection therapy for the treatment of musculoskeletal disorders in which mildly irritating solutions are injected into ligaments, tendons, or joint capsules to cause a mild inflammatory response that stimulates healing.

• prolymphocyte [pro-lim′fo-sīt] a cell of the lymphocytic series inter-mediate between the lymphoblast and lymphocyte.

• promastigote [pro-mas′tľ-gōt] one of the morphological stages in the development of certain protozoa, characterized by a free anterior flagellum and the kinetoplast and axoneme at the anterior end of the body. There is no undulating membrane. They are usually found in arthropods and plants.

• promazine [pro′m -zēn] a phenothiazine tranquilizer.

• promegakaryocyte [pro-meg″ -kar′e-o-sīt] a precursor in the thrombocytic series that is a developmental form intermediate between the megakaryoblast and the megakaryocyte.

• promegaloblast [pro-meg′ -lo-blast] the earliest form in the abnormal erythrocyte maturation sequence occurring in vitamin B₁₂ and folic acid deficiencies in humans; it corresponds to the proerythroblast or rubriblast, and develops into a megaloblast.

• promethazine [pro-meth′ -zēn] a phenothiazine derivative used as an antihistamine, antiemetic, and tranquilizer.

• promethestrol see methestrol.

• promethium (Pm) [pro-me′the- m] a chemical element, atomic number 61, atomic weight 147.

• prometon, prometone a plant hormone herbicide; one of the triazine compounds and capable of causing anorexia, poor weight gain, and muscle weakness if there is excessive contact with animals.

• prometryne see prometon.

• prominence [prom′ľ-n ns] a protrusion or projection.

• promonocyte [pro-mon′o-sīt] a cell of the monocytic series intermediate between the monoblast and monocyte, with an undulating nucleus and coarse chromatin structure.

• promontory [prom′ n-tor″e] a projecting process or eminence.

  • middle ear p. a bulge in the medial wall of the middle ear overhanging the cochlea.
  • sacral p. an obvious prominence in the midline of the ventral surface of the lumbosacral junction, located at the junction of the cranial extremity of the sacrum with its ventral surface.

• promotants includes all agents used to increase the rate of body weight gain. Used principally in food animals but also in horses with a view to increasing muscle mass and physical performance. These uses are now largely illegal. Used in any species to hasten recuperation in animals debilitated by illness. Pharmaceutical preparations are principally anabolic steroids. Husbandry procedures include estrogen and zearalenone implants and dietary supplementation with antibiotics, monensin and, in the case of pigs, copper.

• promoter [pro-mo′t r] a specific DNA sequence immediately adjacent to the transcription start site to which RNA polymerase and other factors bind and signal where RNA synthesis (transcription) should begin.

  • internal p. a class of enhancers that are gene-specific sequences that increase transcription.
  • p. region the non-coding nucleotide sequence at the transcription start region that contains the binding site for RNA polymerase, the transcription start site, and sites where other factors regulating gene expression can bind to.

• prompting a stimulus that gets an animal to perform a desired behavior.

• promyelocyte [pro-mi′ -lo-sīt] a precursor in the granulocytic series, intermediate between myeloblast and myelocyte, containing a few, as yet undifferentiated, cytoplasmic granules. Called also progranulocyte.

• pronate [pro′nāt] 1. in humans, to turn the palm downward or from the body to face the ground; the homologous action in animals; not easily achieved in ungulates, although carried out with facility in most primates, dogs, cats, and many animals that can grasp, such as rodents, kangaroos; compare with supination. 2. eversion and abduction of the foot, raising the lateral margin, only easily achieved in primates.

• pronation [pro-na′sh n] the act of pronating; the plantar surface of the paw is turned to face backward, the customary position in animals other than primates.

• pronator [pro-na′t r] a muscle that pronates an extremity.

• prone [prōn] 1. lying on the ventral surface. 2. predisposed to; tendency toward.

• pronephric [pro-nef′rik] see pronephros.

  • p. duct a duct reaching from the pronephros to the cloaca.
  • p. tubules transient tubules of the primitive kidney that are produced in embryos of the lower vertebrates but in the domestic animals are found only in the sheep; they are nonfunctional in other mammals. Connect the pronephros to the pronephric duct.

• pronephros [pro-nef′ros] pl. pronephroi [Gr.] the primordial kidney; nonfunctional in mammals; functional only in amphioxuses and lampreys; an excretory structure or its rudiments developing in the embryo before the mesonephros; its duct is later used by the mesonephros, which arises caudal to it.

• pronograde walking with the body horizontal, as in quadrupeds; cf. orthograde.

• pronormoblast [pro-nor′mo-blast] rubriblast, proerythroblast.

• pronucleus [pro-noo′kle- s] pl. pronuclei; the haploid nucleus of a sex cell.

  • female p. the haploid nucleus of the fully mature ovum that loses its nuclear envelope and liberates its chromosomes to meet the synapsis with those from the male pronucleus.
  • male p. the nuclear material of the head of a spermatozoon, after it has penetrated the ovum and acquired a pronuclear membrane.

• proof reading 3′→5′ exonuclease activity of DNA polymerase that results in the removal of erroneously incorporated nucleotides during DNA replication; responsible for the very high fidelity (>10⁶) of DNA polymerase.

  • p. r. site a distinct site of aminoacyl-tRNA synthetases that preferentially recognizes and hydrolyzes mis-acylated tRNA.

• pro-otic preauricular.

• propagation [prop″ -ga′sh n] reproduction. spreading, as in propagation of nerve impulses.

• propagule [prop′ -gool] an ecological term; the minimum number of individuals of a species required to colonize an island.

• propanediol see propylene glycol.

• propantheline [pro-pan′th -lēn] an anticholinergic smooth muscle relaxant, used particularly in treating urethral spasm and irritable bowel syndrome. Where available by injection, it is used to facilitate examination per rectum in horses.

• proparacaine [(pro-par′ -kān] the preferred topical anesthetic for ophthalmic use. Called also proxymetacaine hydrochloride.

• proparathyroid hormone (proPTH) [pro-par″ -thi′roid hor′mōn] an intermediate precursor of parathyroid hormone, formed from pre-proparathyroid hormone in the rough endoplasmic reticulum of chief cells.

• propatagiectomy [pro-p -ta″zhe-ek′t -me] surgical removal of part of one of the wing membranes (propatagium) of a bird to prevent it from flying. See also deflighting. Also know as patagiectomy.

• propatagium [pro-p -ta′zhe- m] the web of skin that makes up the wing membrane of birds in front of the elbow and that stretches from shoulder to carpus.

• propazine a triazine broad leaf herbicide. Sprayed pastures may cause poisoning of livestock up to 7 days later. Causes anorexia, weight loss, and muscle weakness.

• propedeutics [pro-p -du′tiks] preliminary instruction; preparatory teaching.

• propentofylline a xanthine derivative glial cell modulator used to improve cognitive function in aged dogs. It acts to improve cerebral blood flow by inhibiting platelet aggregation and thrombus formation.

• propepsin pepsinogen; the inactive precursor of pepsin.

• proper ligament a fold of peritoneum that unites the ovary to the uterus or the testis to the epididymis.

• properdin [pro′p r-din] a normal, relatively heat-labile, nonantibody serum protein (a euglobulin) that, in the presence of complement component C3 and magnesium ions, is involved in the alternative complement pathway, and acts nonspecifically against gram-negative bacteria and viruses and plays a role in lysis of erythrocytes. It may act in conjunction with complement-fixing antibody.

  • p. pathway alternative complement pathway.

• prophage [pro′fāj] the latent stage of a bacteriophage in a lysogenized bacterium, in which the viral genome is inserted within the bacterial host chromosome, usually at a specific location and is replicated with the chromosome. Genes on the prophage may be expressed and contribute to bacterial virulence.

• propham a herbicide and fungicide used as a seed dressing; has little if any toxicity.

• prophase [pro′fāz] the first stage of cell replication in either meiosis or mitosis.

• prophy [pro′fe] in dental terms, prophylaxis; scaling (supragingival and subgingival plaque and calculus removal) and polishing of the teeth with power/hand instrumentation performed by a trained veterinary health care provider under general anesthesia.

  • p. cup a deformable rubber cup that flares when applied to a tooth being polished.
  • p. paste the material used to polish teeth; typically contains an ingredient with abrasive properties (e.g., pumice or silica compounds) of various grades.

• prophylactic [pro″f -lak′tik] to ‘guard before’; a preventive action or agent, e.g., an action or agent that is intended to prevent disease.

  • p. antibiotic therapy treatment with antibiotics, beginning in advance of likely bacterial infection, e.g., just before a surgical procedure (preoperative), to limit or prevent development of infection. See also perioperative.

• prophylaxis [pro″f -lak′sis] prevention of disease; preventive treatment.

  • dental p. a program of calculus and plaque removal, scaling, and polishing teeth, diagnostic studies, oral irrigation, charting, and home care instruction carried out regularly to prevent and control periodontal disease. See also prophy.

• propiocortin [pro″pe-o-kor′t n] precursor protein to ACTH found in the adenohypophyseal pars distalis.

• propiolactone [pro″pe-o-lak′tōn] also known as beta-propriolactone. A disinfectant with bactericidal, sporicidal, fungicidal, and virucidal activities used as a vapor for sterilizing large enclosed spaces. Of limited usefulness because of toxicity and carcinogenic properties. Commonly used as a inactivating agent in the production of viral vaccines.

• propiomazine [pro″pe-o-ma′zēn] a phenothiazine derivative used as a tranquilizer or premedication for general anesthesia, with actions and adverse effects similar to acepromazine; also has antiemetic and antihistaminic actions.

• propionanilide a hormone weedkiller that is likely to be toxic only if massive doses are administered.

• propionate [pro′pe-o-nāt] any salt of propionic acid. A precursor for glucose in the ruminant.

  • sodium p. used as a prophylactic against primary ketosis in cows.

• Propionibacterium [pro″pe-on″ľ-bak-tēr′e- m] gram-positive pleomorphic rods which are common skin residents, found also in dairy products and the alimentary tract.

  • P. acnes activates macrophages, increases proliferation of lymphoblasts, and stimulates resistance to bacterial infection. Used as a bacterial immunostimulant.

• propionic acid [pro″pe-on′ik] CH₃CH₂COOH, found in chyme and sweat, and one of the products of bacterial fermentation of wood pulp waste; also an important gluconeogenic volatile fatty acid synthesized by the ruminal microflora. Its salts (calcium and sodium propionate) are used as mold inhibitors in stock feeds and pharmaceuticals, and in topical antifungal preparations.

• propionyl CoA [pro′pe- -n l] activated intermediate in the utilization of the volatile fatty acid, propionic acid; or end product of the beta-oxidation of odd-carbon chain fatty acids.

• propionylpromazine [pro′pe- -nl-pro′m -zēn] a phenothiazine derivative used as a tranquilizer, usually in combination with methadonea phenothiazine derivative used as a tranquilizer or premedication for general anesthesia, with actions and adverse effects similar to acepromazine; also has antiemetic and antihistaminic actions.

• propiopromazine [pro′pe- -pro′m -zēn] propionylpromazine.

• proplatelets [pro″plāt′l ts] elongated strands of megakaryocyte cytoplasm that extend into the bone marrow sinuses; fragmentation produces platelets.

• proplexus [pro″plek′s s] the choroid plexus of the lateral ventricle of the brain. Called formally: plexus choroideus ventriculi lateralis.

• propofol [pro′po-fol] a rapidly acting, short duration, intravenous hypnotic anesthetic induction agent. The active ingredient is 2,6-di-isopropylphenol.

• proportion [pr -por′sh n] percentage or fraction of a whole. Often expressed also as a rate or ratio by comparison to a total or other population.

  • p. differences estimating the significance of differences between two proportional morbidities or mortalities.

• proportional values expressed as a proportion of the total number of values in a series.

  • p. morbidity a percentage estimate of the morbidity of a disease in a group. See also proportional morbidity.
  • p. mortality the mortality rate due to a specific disease in a group expressed as a proportion of all of the causes of death in the group. See also mortality rate.

• propositus [pro-poz′ľ-t s] pl. propositi [L.] the original animal presenting a disease or disorder that serves as the basis for a hereditary or genetic study; called also proband.

• propoxur a carbamate insecticide used widely on companion animals to control ectoparasites. Also used to control mosquitoes and ants and as a molluscicide.

• propoxycaine [pro-pok′sľ-kān] a local anesthetic with longer action than procaine. Removed from the US market in 1996.

• propoxyphene [pro-pok′sľ-fēn] a weak opioid analgesic, used as the hydrochloride and napsylate salts. Also called dextropropoxyphene.

• proppy a gait in which the animal’s movements are stilted with a lack of flexion of the knees and pasterns; usually used in describing horses.

• propranolol [pro-pran′ -lol] a non-selective β-adrenoceptor blocking agent, useful in the treatment of cardiac dysrhythmias including paroxysmal tachycardia, atrial flutter, and fibrillation.

• proprietary medicine [pro-pri′ -tar-e] any chemical, drug, or similar preparation used in the treatment of diseases, if such article is protected against free competition as to name, product, composition, or process of manufacture by secrecy, patent, trademark, or copyright, or by other means.

• proprioception [pro″pre-o-sep′sh n] awareness (by the brain) of the position of body parts in three-dimensional space, mediated by proprioceptors or proprioceptive tissues. Often divided into conscious proprioception (also referred to as kinesthesia in people) and unconscious proprioception. Conscious proprioception is thought to be mediated by the cerebral cortex, while unconscious proprioception is mediated by the cerebellum. Proprioception is assessed in the neurological examination by means of proprioceptive function tests, such as paw position, and hopping tests.

• proprioceptive [pro″pre-o-sep′tiv] pertaining to or emanating from proprioceptor.

  • p. deficit a defect of proprioception in which the animal acts as though it does not know where its feet are (in contrast to a cerebellar defect when the feet do not end up where the animal appears to intend that they should go).
  • p. positioning positioning of the limbs or head and neck in response to proprioceptive inputs. The basis of postural reflexes.
  • p. reflex a reflex that is initiated by stimuli arising from some function of the reflex mechanism itself.

• proprioceptor [pro″pre-o-sep′t r] any of the sensory nerve endings that give information concerning movements and position of the body; they occur chiefly in muscles, tendons, and the labyrinth.

• proprotein [pro-pro′tēn] a protein that is cleaved to form a smaller protein, e.g., proinsulin, the precursor of insulin.

• proPTH proparathyroid hormone.

• proptosis [prop-to′sis] marked exophthalmos (forward displacement of the eye) so that the eyelids are behind the globe equator. An ocular emergency.

• propyl [pro′p l] the univalent radical CH₃CH₂CH₂, from propane.

  • p. disulfide the toxic principle in Allium spp. Called also n-propyl disulfide.

• propylene glycol [pro′p -lēn] a chemical used industrially as an antifreeze, a solvent stabilizer, a preservative in liquid livestock feeds, and pharmaceutically as a vehicle or solvent for medicinal preparations. It is also used orally in food animal medicine to elevate the blood glucose concentration in ruminants with ketosis (hyperketonemia). Doses that are innocuous to cows can cause ataxia, depression, and death in horses. Also called propanediol.

• propylene oxide [pro′p -lēn] a gas used to disinfect animal feeds.

• propyliodone [pro″p l-i′o-dōn] a radiopaque medium used in bronchography.

• propylparaben [pro″p l-par′-b n] an antifungal agent used as a preservative in pharmaceuticals.

• propylthiouracil [pro″p l-thi″o-u′r -sil] a thyroid inhibitor used in the treatment of feline hyperthyroidism, but because of hepatopathy and severe hematologic toxicity in cats, other drugs are preferred.

• prorennin [pro′re-nin] the zymogen (proenzyme) in the gastric glands that is converted to chymosin.

• prorubricyte [pro-roo′brľ-sīt] in the maturation of erythrocytes, the cell that follows the rubriblast. Called also basophilic normoblast.

• Prosarcoptes a genus of mange mites in the family Sarcoptidae.

  • P. faini, P. pitheci, P. scanloni found on monkeys.

• prosecretin [pro″se-kre′tin] the precursor of secretin.

• prosection [pro-sek′sh n] carefully programmed dissection for demonstration of structure.

• prosector [pro-sek′t r] one who performs prosection.

  • p’s wart infection of the skin of humans by Mycobacterium tuberculosis picked up while dissecting infected tissue.

• prosencephalic [pros″ n-sef-al′ik] pertaining to or emanating from prosencephalon.

  • p. hypoplasia a congenital malformation in calves; there is a small opening on the surface of the calvaria; the hole connects with a deformed diencephalon that may discharge cerebrospinal fluid.

• prosencephalon [pros″ n-sef′ -lon] the telencephalon and diencephalon; known also as the forebrain.

• prosencephaly [pros″ n-sef′ -le] fusion of the cerebral hemispheres with a single lateral ventricle.

• prosimian member of the order Primate, other than simians (monkeys and apes); includes aye-ayes, bush babies, lemurs, tarsiers, and lorises. Native to Africa, Asia, and Madagascar.

• pros(o)- word element. [Gr.] forward, anterior.

• prosodemic [pros″o-dem′ik] passing directly from one animal to another instead of reaching a large number at once, through such means as water supply; said of a disease progressing in that way.

• Prosopis [pro-so′pis] American plant genus in the legume family Fabaceae, including P. juliflora (mesquite), P. glandulosa (honey mesquite), algarroba, and kiawe; can cause chronic liver damage in cattle, sheep, and goats.

• prosoplasia [pros″o-pla′sh ] 1. abnormal differentiation of tissue. 2. development into a higher state of organization or function.

• prosop(o)- word element. [Gr.] relationship to the face.

• prosopoplegia [pros″o-po-ple′j ] facial paralysis.

• prosoposchisis [pros″o-pos′kľ-sis] congenital fissure of the face.

• prosopospasm [pros″o-po-spaz′ m] spasm of the facial muscles.

• prosoposternodymia [pros″o-po-st r-no-dī′-me-] conjoined twins joined face to face and sternum to sternum.

• prosopothoracopagus [pros″o-po-thor″ -cop′-g s] twin fetuses fused from the face to the thorax.

• prospective [pr -spek′tiv] not yet done; in the future.

  • p. history maintaining a surveillance over a patient in order to accumulate a history of an illness after the initial attack.
  • p. study see prospective study.
  • p. surveillance an epidemiological strategy of maintaining a watch over a suspected population after an event.
  • p. trial in a field trial of a preventive or therapeutic regimen the trial can be conducted in a series of consequential or contingent steps with each step contingent on the results in the one preceding it.

• prostacyclin (PGI₂) [pros″t -si′klin] an eicosanoid metabolite of arachidonic acid formed by cyclo-oxygenases in the walls of arteries and veins; it is a potent vasodilator and an inhibitor of platelet aggregation. The exogenous form is called epoprostenol.

• prostaglandin [pros″t -glan′din] a group of naturally occurring, chemically related, long-chain hydroxy fatty acids (eicosanoids) belonging to the prostanoid class of fatty acid derivatives; they stimulate contractility of the uterine and other smooth muscle and may cause constriction or dilation of vascular smooth muscle, they have the ability to lower blood pressure, regulate acid secretion of the stomach, regulate body temperature and platelet aggregation, and control inflammation and vascular permeability. They also affect the action of certain hormones. First found in semen, they have since been found in cells throughout the body. There are six types, A, B, C, D, E, and F, the degree of saturation of the side chain of each being designated by subscripts 1, 2, and 3. The main use of prostaglandins in veterinary medicine is in the treatment and regulation of activity of the female reproductive tract. The F series promotes myometrial activity and luteolysis. Precise effects of E series are mediated by specific receptor activated; receptors in the reproductive tract are regulated by steroid hormones.

  • p. F_1α promotes platelet aggregation; actively removed from the circulation by the vascular endothelium.
  • p. I₂ see prostacyclin.
  • p. synthase complex see cyclo-oxygenase.

• prostanoid [pros′t -noid] having the form of a prostaglandin; a class of eicosanoids that includes prostaglandins, thromboxanes, and prostacyclins.

• prostate [pros′tāt] a gland in the male that surrounds the neck of the bladder and the urethra. It is a diffuse gland in rams and goat bucks, a lobed gland in stallions and dogs, and a combination of lobed and diffuse in bulls and boars. The prostate consists of glandular tissue, the ducts from which empty into the prostatic portion of the urethra, and partly of muscular fibers that encircle the urethra. It contributes to the seminal fluid a secretion containing acid phosphatase, citric acid, and proteolytic enzymes, which account for the liquefaction of the coagulated semen. The rate of secretion increases greatly during sexual stimulation.

• prostatectomy [pros″t -tek′t -me] surgical removal of the prostate.

• prostatic [pros-tat′ik] pertaining to or emanating from the prostate.

  • p. abscess occurs in dogs, often as a complication of prostatitis, benign prostatic hypertrophy, and squamous metaplasia. Clinical signs are variable, sometimes resembling those of acute prostatitis with fever and systemic illness, or they can be similar to those of chronic prostatitis with straining, dysuria, and hematuria.
  • benign p. hyperplasia diffuse glandular and stromal hyperplasia and hypertrophy of the prostate commonly seen in dogs from middle age, increasing in frequency and degree with advancing age. Castration usually reverses it. Clinical effects include constipation and less often dysuria. Infection can be a complication, causing acute or chronic prostatitis.
  • p. calculi occur uncommonly in dogs. May originate in the urinary tract, becoming lodged in the prostate, or form within prostatic tissue.
  • p. cyst may occur within the prostate in association with benign prostatic hyperplasia or as a separate entity (paraprostatic cysts), developing from vestiges of müllerian ducts. Large cysts may cause difficulty with urination or defecation.
  • p. fluid the liquid secretion of the prostate, which contributes to semen formation; the third, sperm-free, fraction in a dog semen collection.
  • p. inflammation see prostatitis.
  • p. massage firm digital pressure and massage of the prostate, applied per rectum, may be performed to increase the amount of cellular material and secretions collected in a urine or prostatic wash sample.
  • p. neoplasms adenocarcinomas occur infrequently in older dogs, invading locally and metastasizing to sublumbar lymph nodes and lumbar vertebrae.
  • p. wash placement of a urinary catheter in the prostatic urethra and a saline flush followed by aspiration of fluid is used to obtain samples for culture and cytology in the diagnosis of prostatic disease in dogs.

• prostatitis [pros″t -ti′tis] inflammation of the prostate. Occurs mostly in dogs where it may be chronic, causing dysuria, hematuria, and tenesmus; or acute, causing fever, leukocytosis, pain, and gait abnormalities in addition. Constipation may accompany some chronic cases.

• prostatocystitis [pros″t -to-sis-ti′tis] inflammation of the neck of the bladder (prostatic urethra) and the bladder cavity. The clinical syndrome is a combination of those of cystitis and prostatitis.

• prostatocystotomy [pros″t -to-sis-tot′ -me] incision of the bladder and prostate.

• prostatolith [pros-tat′o-lith] see prostatic calculi.

• prostatolithotomy [pros″t -to-lľ-thot′ -me] incision of the prostate for removal of a calculus.

• prostatomegaly [pros″t -to-meg′ -le] enlargement of the prostate.

• prostatorrhea [pros″t -to-re′] catarrhal discharge from the prostate.

• prostatotomy [pros″t -tot′ -me] surgical incision of the prostate.

• prostatovesiculitis [pros″t -to-v -sik″u-li′tis] inflammation of the prostate and seminal vesicles.

• Prosthenorchis a genus of parasites in the phylum Acanthocephala or thorny-headed worms.

  • P. elegans, P. spirula (syn. P. sigmoides) found in the terminal small intestine, colon, and cecum of monkeys. Heavy infestations cause diarrhea, dehydration, and death. There are yellow nodules on the serosal surface of the intestine that is swollen. There may be obstruction of the ileocecal valve and perforation of the intestinal wall.

• prosthesis [pros-the′sis] pl. prostheses [Gr.] 1. the replacement of a body part by an artificial substitute. 2. a substitute for a missing part, such as an eye, leg, or tooth, used for functional or cosmetic reasons, or both.

  • femoral p. see total hip replacement.
  • joint p. the principal example in veterinary surgery is total hip replacement.
  • ocular p. cosmetic but nonfunctional replacement for an eye. May be fitted within the orbit after enucleation (intraorbital), within the sclera after evisceration of the defective ocular structures (intrascleral), or over the surface of a deformed eye (extrascleral).
  • skeletal p. not commonly used in animals, largely because of the great variability in the sizes required and the relatively small demand. Prosthetic limbs are occasionally used in horses following amputation.
  • urethral p. metal or synthetic conduits may be implanted in the treatment of urethral stricture and obstruction in male cats.

• prosthetic [pros-thet′ik] serving as a substitute; pertaining to prostheses or to prosthetics.

  • p. implants see prosthesis, carbon fiber implants.

• prosthetics [pros-thet′iks] the field of knowledge relating to prostheses, their design, use, etc.

• prosthetist [pros′th -tist] a person skilled in prosthetics and practicing its application.

• proptometer [prop-tom′ -t r] an instrument for measuring the degree of exophthalmos.

• prosthodontics [pros″tho-don′tiks] a speciality in dentistry and oral surgery that is concerned with the provision of suitable substitutes for the clinical crown of teeth or for one or more missing or lost teeth and their associated parts. Maxillofacial prosthetics is considered a subspecialty of prosthodontics, involving palatal obturators, and maxillofacial prostheses to replace resected or lost tissues. Called also dental prosthetics, prosthetic dentistry.

• Prosthogonimus [pros″tho-gon′ľ-m s] a genus of flukes (digenetic trematodes) in the family Prosthogonimidae which parasitize birds but are found occasionally in mammals.

  • P. anatinus found in domestic ducks.
  • P. cuneatus found in swans.
  • P. macrorchis, P. ovatus found in the bursa of Fabricius and oviduct of domestic poultry and wild birds.
  • P. oviformis found in ducks.
  • P. pellucidus occurs in the bursa of Fabricius, oviduct, and posterior intestine of fowl, ducks, and wild birds.

• prosthokeratoplasty [pros″tho-ker′ -to-plas″te] surgical replacement of a damaged section of cornea by an inert graft.

• Prosthorhyncus formosus an acanthocephalan parasite found in the small intestine of domestic fowl and some wild bird species. Has doubtful pathogenicity.

• prostration [pros-tra′sh n] extreme exhaustion, or lack of energy or power.

• protactinium (Pa) [pro″tak-tin′e- m] a chemical element, atomic number 91, atomic weight 231.

• protamine [pro′t -mēn] any of a class of basic proteins, soluble in water, not coagulated by heat, and precipitated from aqueous solution by addition of alcohol, found combined with nucleic acids in the sperm of certain fish, and having the property of neutralizing heparin. Protamine sulfate is used as an antidote to heparin overdosage.

  • p. zinc insulin (PZI) see insulin.

• protandry, protogyny in sequential hermaphroditism, which occurs in certain species of fish, the individual changes sex during its life; in protandry the change is from male to female, protogyny is the reverse.

• protean [pro′te- n] changing form or assuming different shapes; versatile.

• protease [pro′te-ās] any proteolytic enzyme.

  • p.–antiprotease imbalance thought to play a part in the pathogenesis of emphysema by permitting excessive proteolysis, especially of elastin.
  • fecal p’s. originate from the pancreas and include trypsin, chymotrypsin, and carboxypeptidases. Proteolytic activity of the feces may be evaluated by tests that measure digestion of gelatin or caseinbased substrates.
  • α₁-p. inhibitor (α₁-PI) a plasma protein normally lost into the gastrointestinal tract; because it is a protease inhibitor, it is resistant to degradation. Measurement in feces by immunoassay is used in dogs and cats to assess abnormalities of gastrointestinal protein loss as occurs in inflammatory gastroenteropathies, protein-losing enteropathies, small intestinal bacterial overgrowth, and neoplasia.

• proteasome large protein complex responsible for the degradation of unneeded, misfolded or damaged proteins; functions in concert with ubiquitin, which tags proteins for breakdown.

• protectant, protective [pro-tek′t nt] 1. affording defense or immunity. 2. an agent affording defense against harmful influence.

  • intestinal p. a preparation that given orally provides a protective coating for the intestinal mucosa, and absorbs bacteria and toxins. Kaolin, pectin, and activated charcoal are commonly used for this purpose.

• protection prevention against injury.

  • radiation p. limiting the exposure of personnel and patients to radiation. This includes performing radiography, CT, and scintigraphy only in designated areas, limiting access to areas where this is performed, the use of portable warning signs when radiography is done in the field, the wearing of personal protective equipment by staff working with radiation. Personnel working with radiation should wear dosimeter badges that are checked periodically.
  • p. tests neutralization tests using serial dilutions of antiserum to protect animals against challenge by a standard dose of microorganism. Also used to describe tests performed to assess the efficacy of a vaccine to prevent disease after experimental challenge with a pathogen.

• protective [pro-tek′tiv] 1. providing protection. 2. substances used to provide protection to tissues.

  • p. clothing varies with the risk prevailing, e.g., radiation (see x-ray protection), waterproof gear for highly infectious diseases, coveralls for normal large animal practice, metal studded gloves for catching aggressive companion animals.
  • p. substances finely ground, absorbent, insoluble, inert substances that absorb toxins, cover sensitive and damaged tissues with a fine film. Includes starch, kaolin, talc, zinc oxide, zinc stearate. See also intestinal protectant.

• protein [pro′tēn] any large organic compound made from one or more polypeptides, which are chains of amino acids joined in a genetically determined order by peptide linkages between the carboxyl group of one amino acid and the amino group of the next. They contain carbon, hydrogen, oxygen, and nitrogen and usually sulfur, occasionally phosphorus. Proteins form a large and essential part of the body mass, comprising especially cell membranes, connective tissue, muscles, enzymes, hormones, blood proteins. To maintain this mass, the diet must contain a high proportion of protein, especially in growing animals and those recovering from debilitating diseases.

  • p. A a surface protein of Staphylococus aureus that binds to the Fc region of some IgG molecules. Fluorochrome-labeled protein A is used in an indirect immunofluorescence test for detecting bound immunoglobulins.
  • acid detergent fiber insoluble p. see unavailable protein (below).
  • authentic p. a recombinant protein with all its naturally occurring properties.
  • available p. the portion of dietary protein that can be used by the animal.
  • p. binding a property of many drugs that limits their distribution and availability in the blood, as well as affecting elimination from the body.
  • p. bumps see bumps.
  • bypass p. see protected protein and escape protein (below).
  • p. C a vitamin K–dependent plasma protein with anticoagulant effects, synthesized by the liver and involved in regulation of fibrin clot formation. Decreased plasma concentration may be caused by decreased hepatic or hepatoportal function, vitamin K deficiency, or increased consumption in disseminated intravascular coagulation or sepsis.
  • p.-calories calories derived from proteins in the diet.
  • p. calorie malnutrition inadequate protein in the diet leads to impaired cell-mediated immunity, delayed wound healing, and loss of lean body mass.
  • p.–calorie ratio the number of calories provided from protein sources, compared with the total caloric intake; an indication of the level of protein intake.
  • carrier p. one that, when coupled to a hapten, renders it capable of eliciting an immune response.
  • chimeric p. see fusion protein.
  • competitive p. binding (CPB) binding proteins occur naturally and have affinity for other substances, for example, sex hormone steroid-binding globulin. The property is made use of in the assay of such substances in body fluids and tissues.
  • complete p. one containing the essential amino acids in the proportion required in the diet.
  • p. concentrates feeds containing a high concentration of protein, e.g., legume grains and forages, meat meal, fish meal, oil cakes, milling residues including bran, shorts, middlings, brewer’s grains.
  • conjugated p’s those in which the protein molecule is united with nonprotein molecules or prosthetic groups, e.g., glycoproteins, lipoproteins, and metalloproteins.
  • urine p.–creatinine ratio (UPC) a quantitative test for urinary excretion of protein. Creatinine, which is excreted as a constant in healthy individuals or those with stable renal disease, is used as a marker to compensate for the wide variation in urine specificy gravity that normally occurs.
  • crude p. the total nitrogen content of a feed multiplied by 6.25. Includes several obvious errors but is still a close approximation of the protein content.
  • dietary p. is usually the most expensive part of the diet, except for animals at pasture, and the constituent most likely to be deficient. An excess of protein in the diet in ruminants can cause a sharp rise in alkalinity, due to the release of ammonia, of the ruminal contents causing ruminal atony and indigestion.
  • digestible p. the crude protein ingested less the protein excreted in the feces. The estimation requires a digestibility trial involving animals, but in feed analysis reports is generated using some percentage of the crude protein value, such as 70% or 72%.
  • p. equivalent said of a feed. The total nitrogen content expressed as protein if it were all in that form. That is the percentage nitrogen in the feed multiplied by the average percentage of nitrogen in plant protein (6.25%).
  • escape p. the proportion of dietary crude protein that is not digested in the rumen, but escapes intact to the lower tract.
  • p. excretion t. one that uses ⁵¹Cr-labeled protein that measures protein excretion in the feces in cases of protein-losing enteropathy.
  • external p. see membrane proteins.
  • p.–fibrinogen ratio an indicator of significant changes in fibrinogen concentrations, taking into account dehydration.
  • fibrous p’s characterized by shape, structure, and low water solu-bility; they have a structural role. Examples are collagen, keratin, and tropomyosin.
  • fusion p. a protein consisting of at least two genes, or portions thereof, that have been joined so that they result in the production of a single polypeptide. For example, when a foreign gene is inserted into a plasmid vector to interrupt a gene, such as lacZ, the mRNA transcript of the recombinant plasmid contains the lacZ Shine–Dalgarno sequence and codons of the 5′ end of the lacZ gene protein followed by the codons of the foreign gene; the protein expressed is a fusion protein containing a few N-terminal lacZ amino acids and the contiguous foreign protein.
  • p. hydrolysates pharmaceutical preparations used in the treatment of severe, acute protein loss. Available for use orally or parenterally. They are partly digested proteins and contain a mixture of polypeptides, amino acids, and other breakdown products. Also included in commercial petfood products specifically forumulated for dogs and cats with food allergies.
  • link p’s. stabilize the aggregates of proteoglycans and hyaluronan in ground substance in supportive tissues forming large bottle-brush-like configurations.
  • p. microarray an ordered set of small samples of proteins immobilized on a microscope slide or other solid surface that is used to determine protein–protein interactions.
  • myeloma p. see multiple myeloma.
  • p. nutritional deficiency causes lack of muscle development, and slow growth rate and maturation. In adults, there is a low milk production and evidence of poor weight gain. In severe states, tissue and blood concentrations fall, hypoproteinemic edema may occur, and a degree of immunosuppression could be expected.
  • omega p. topoisomerase I of Escherichia coli.
  • partial p. one having a content of essential amino acids inadequate for the maintenance of good health. Called also incomplete protein.
  • peripheral p. any protein located in the membrane but not essential to the reconstitution of that membrane. As opposed to integral membrane proteins.
  • plasma p’s all the proteins present in the blood plasma, including the immunoglobulins. See plasma protein.
  • polyhedrin matrix p. a protein that comprises the major component of occlusion bodies produced by nuclear polyhedrosis virus and cytoplasmic polyhedrosis virus; the strong polyhedrin promoter is utilized in the expression of recombinant proteins in baculovirus expression systems.
  • protected p. feedstuffs high in protein that are treated to reduce their amount of digestion by rumen microbes. Treatments include formaldehyde, sodium hydroxide, heating with sulfiteliquor and xylose.
  • rec A p. a multifunctional enzyme that binds to DNA and plays an important role in genetic recombination and DNA repair.
  • p. S a circulating vitamin K–dependent protein with anticoagulant effects.
  • serum p. proteins in the blood serum, including immunoglobulins, albumin, complement, and enzymes.
  • p. shock anaphylaxis occurring after the intravenous injection of protein.
  • p.-sparing in times of energy deficiency the animal body may raid protein stores for glucogenic amino acids, thus depleting body stores of proteins. Substances such as acetic acid that can fill the energy deficiency and avoid the protein loss are known as protein-sparing.
  • p. supplements feeds that contain more than 20% protein.
  • total p. albumin and all globulins in the blood if measurements are done on plasma. When done on serum, they do not include those consumed in clot formation, mainly fibrinogen. Increased concentration occurs in dehydration, inflammation, lymphoid neoplasia, and multiple myeloma. Decreased concentration occurs with protein loss or hemodilution.
  • unavailable p. the insoluble protein fraction, which is unavailable to the animal due to heat damage. Also called acid detergent fiber insoluble crude protein, bound protein, insoluble protein.
  • urine p. see proteinuria.
  • viral p. proteins encoded by the viral genome.

• protein-bound said of a chemical bonding of calcium, iodine, iron, copper, and other electrolyte ions in the blood to plasma proteins. The bound electrolyte is not immediately available biologically nor is it as vulnerable to sudden loss.

  • p.-bound iodine (PBI) test determination of thyroid function by measuring the amount of iodine contained in compounds bound to plasma proteins. It has been largely replaced by radioimmunoassay for the thyroid hormones thyroxine (T₄) and tri-iodothyronine (T₃).

• proteinaceous [pro″tēn-a′sh s] pertaining to or of the nature of protein.

• proteinase [pro′tēn-ās] any enzyme that catalyzes the splitting of interior peptide bonds in a protein; an endopeptidase.

  • p. resistant protein (prp) a protein that resists digestion by proteinases; the amyloid fibrils in brain tissue of sheep affected with scrapie contain such a prp. Called also protease resistant protein.

• proteinemia [pro″tēn-e′me- ] hyperproteinemia.

• proteinosis [pro″tēn-o′sis] the accumulation of excess protein in the tissues.

  • pulmonary alveolar p. an alveolar filling disorder reported in dogs.

• proteinuria [pro″te-nu′re- ] an excess of serum proteins in the urine; an important indicator of renal disease. It is a constant finding in glomerulonephritis, renal infarction, amyloidosis, and nephrosis, but is also common in congestive heart failure and renal ischemia of all kinds. The significance of proteinuria as an indicator of renal disease is greatly enhanced by the presence of renal casts in the urine.

  • Bence Jones p. see Bence Jones protein.
  • glomerular p. results from increased permeability of the glomerular membrane.
  • hemorrhagic p. plasma proteins or hemoglobin enter the urine because of inflammation or hemorrhage in the genitourinary tract. Called also inflammatory or postrenal proteinuria.
  • neonatal p. occurs transiently during the period of intestinal absorption of proteins, some of which are small enough to pass through the glomerular membrane. Called also postcolostral proteinuria.
  • postrenal p. see hemorrhagic proteinuria (above).
  • prerenal p. when plasma concentration of small proteins that pass glomerular filtration is high, the amounts may exceed the capacity of tubules to resorb completely, resulting in proteinuria. Called also overflow and overload proteinuria.
  • tubular p. caused by defective renal tubules that do not resorb proteins filtered by the glomerulus.

• Proteobacteria a phylum of gram-negative bacteria. Divided into five classes, the Alphaproteobacteria (which includes the families Anaplasmataceae, Bartonellaceae, Brucellaceae, and Rickettsiaceae, among others), Betaproteobacteria (which includes the orders Burkholderiales and Neisseriales, among others), Gammaproteobacteria (which includes the families Aeromanadaceae, Coxiellaceae, Enterobacteriaceae, Francisellaceae, Legionellaceae, Moraxellaceae, Pasteurellaceae, Pseudomonadaceae, and Vibrionaceae, among others), Deltaproteobacteria (which includes the pathogenic species Lawsonia intracellularis, among others), and Epsilonproteobacteria (which contains the families Helicobacteraceae and Campylobacteraceae).

• Proteocephalus a genus of tapeworms in the order Proteocephalidea, primarily as intestinal parasites of fresh-water fish.

  • P. ambloplitis found in cultured fish, especially bass. The parasite affects the gonads and causes sterility. Called also bass tapeworm.

• proteoglycan [pro″te-o-gli′kan] any of a group of heavily glycosylated glycoproteins found primarily in connective tissue and formed of subunits of glycosaminoglycans (long polysaccharide chains containing amino sugars) linked to a protein core like bristles on a bottle brush. Hydrated proteoglycans form the highly viscous fluid of mucus and the matrix of the intercellular ground substance of connective tissue. Called also mucopolysaccharide.

• proteolipid [pro″te-o-lip′id] a combination of a peptide or protein with a lipid, having the solubility characteristics of lipids.

• proteolysis [pro″te-ol′ľ-sis] the splitting of proteins by hydrolysis of the peptide bonds, with formation of smaller polypeptides.

• proteolytic [pro″te-o-lit′ik] 1. pertaining to, characterized by, or promoting proteolysis. 2. a proteolytic enzyme.

  • p. enzyme any protease; includes pepsin from the stomach; trypsin, chymotrypsin, elastase, carboxypeptidase A and B, all from the exocrine pancreas; enteropeptidase, aminopeptidase, dipeptidase, all from the intestinal mucosa; collagenase; cathepsins; proteins of the blood clotting cascade, complement system, and apoptosis pathway.

• proteome [pro′te-ōm] the entire complement of proteins made by a single organism; includes splice variants and post-translational modifications such as glycosylation and phosphorylation.

• proteometabolism [pro″te-o-m -tab′-liz- m] the metabolism of protein.

• proteomics [pro″te-o′miks] the comprehensive analysis of the identity, interactions, and locations of proteins within a cell.

• proteopeptic [pro″te-o-pep′tik] digesting protein.

• proteoses [pro′te-ōs- s] a mixture of split products formed by the hydrolysis of protein molecules short of the amino acid stage.

• proteroglypha [pro″t r-og′lif-] members of the proteroglyphous group of elapid snakes, which have short, hollow fangs to deliver their potent venom. Typically strike their prey and continue with bite until the venom has taken effect. See Elapidae Proteromonas flagellate protozoa found in the intestines of all lizards; not thought to be pathogenic.

• Proteus [pro′te- s] a genus of gram-negative, motile bacteria, members of the family Enterobacteriaceae, usually found in fecal and other putrefying matter. Also found associated with infections of the external ear and skin and in pyometra and pyelonephritis.

  • P. mirabilis a common inhabitant of animal fecal material found particularly in infections of the eye, skin, urinary, and respiratory tracts.
  • P. morganii a common inhabitant of animal fecal material and a common opportunistic pathogen. Called also Morganella morganii.
  • P. vulgaris found in canine epididymo-orchitis, prostatitis, and cystitis.

• prothrombin [pro-throm′bin] a glycoprotein present in the plasma that is converted into thrombin by extrinsic thromboplastin during the second stage of blood clotting; called also clotting factor II.

  • p. consumption test determines thromboplastin generating capacity, which provides information about the first stage of coagulation. When clotting of a normal blood sample occurs, prothrombin is converted to thrombin, thus there should be little or no prothrombin in the serum after the clot is formed. If, however, there is deficiency of blood coagulation, some of the prothrombin will not be utilized (consumed). Abnormal results of the test are found in deficiencies of the first-stage factors of coagulation (factors VIII and IX), and in the presence of circulating anticoagulants, thrombocytopenia, and any other condition leading to inadequate generation of thromboplastin. Called also serum clot time.
  • p. converting activity the step in blood coagulation in which factor Xa, together with factor Va react with phospholipid in the presence of calcium, activates prothrombin to form thrombin.
  • p. deficiency see hypoprothrombinemia.
  • p. time (PT) test a functional test that measures the extrinsic and common coagulation pathways. A sensitive indicator of poisoning with anticoagulant rodenticides. The one-stage (OSPT) test is performed by measuring the time required for clot formation after tissue extract and calcium are added to citrated plasma. Called also Quick’s prothrombin test. A two-stage test determines plasma concentrations of prothrombin by finding the dilution of plasma that clots a standard fibrinogen reagent in a set period of time.

• prothrombinase [pro-throm′bin-āse] thromboplastin; tissue factor, factor III.

• prothrombinogenic [pro-throm″bľ-no-jen′ik] promoting the production of prothrombin.

• protirelin [pro-ti′r -lin] thyrotropin releasing hormone.

• protist [pro′tist] any member of the Protista.

• Protista [pro-tis′t ] a kingdom comprising bacteria, algae, slime molds, fungi, and protozoa; it includes all single-celled prokaryotic organisms.

• protium [pro′te- m] themass 1 isotope of hydrogen, symbol ¹H; ordinary, or light, hydrogen.

• prot(o)- word element. [Gr.] first.

• protoanemonin [pro″to- -nem′o-nin] pentadienoic lactone in all members of the plant family Ranunculaceae. In the living plant, it is present as an inert glycoside ranunculin. When it is released enzymatically it is irritant, causing erythema and blistering of the skin and mucosae. See also Ranunculus.

• protoblast [pro′to-blast] 1. a cell with no cell wall; an embryonic cell. 2. a blastomere from which a particular organ or part develops.

• protocol [pro′to-kol] 1. the original notes made on a necropsy, an experiment, or on a case of disease. 2. a detailed plan for an experiment, a course of treatment, a procedure. Used to describe complex treatment plans for chemotherapy. See CDP (2), CHOP, COAP, COP, DMAC, MOPP, UW-M.

  • special p. (1) a hospital case chart created specially to record observations in cases of a disease that is under examination by members of the staff.
  • rescue p. (2) chemotherapy protocols used to reinstate remission when a relapse has occurred after a previously successful course of treatment.

• protocollagen [pro″to-kol′ -j n] an abnormal form of collagen when the hydroxylation stage of its formation is interrupted.

• protodiastole [pro″to-di-as′to-le] the beginning of ventricular relaxation, terminating when the semilunar valves close.

• protodiastolic [pro″to-di″ -stol′ik] pertaining to early diastole, i.e., immediately following the second heart sound.

• protoduodenum [pro″to-doo″o-de′n m] the first or proximal portion of the duodenum, extending from the pylorus to the duodenal papilla.

• protofibril [pro″to-fi′bril] the first elongated unit appearing in formation of any type of fiber.

• protofilament [pro″to-fil′ -m nt] a filament formed by the aggregation of tubulin in the form of microtubules; a stage in the development of the cytoplasmic skeleton.

• protogaster [pro′to-gas″t r] archenteron.

• protogyny [pro-toj′ľ-ne] see protandry.

• protokylol a sympathomimetic agent with activity similar to isoproterenol. Used as a bronchodilator.

• Protolepsis tesselata a species of leech that commonly parasitizes the nasal cavity of aquatic birds.

• proton [pro′ton] 1. an elementary particle of mass number 1, with a positive charge equal to the negative charge of the electron; a constituent particle of every nucleus, the number of protons in the nucleus of each atom of a chemical element being indicated by its atomic number. 2. common synonym for the hydrogen ion, H⁺, which consists of only one proton.

  • p. pump see H⁺,K⁺-ATPase.
  • p. pump inhibitors (PPI) benzimidazoles, a class of drugs that act by irreversibly inhibiting the hydrogen/potassium ATPase enzyme system in gastric parietal cells, thereby reducing gastric acidity. Used to prevent and treat gastrointestinal ulcers in dogs, cats horses, and exotic species. Includes omeprazole.
  • p. density weighted scan in magnetic resonance imaging (MRI), displays the relative proton density between tissues. A longer time delay is used between excitation radiofrequency pulses and the time set to receive the peak echo signal is shorter than for other MRI scans. Fat and fluid are bright, soft tissues and are displayed as various shades of gray, and tendons, ligaments, air and cortical bone are dark.

• protoneuron the first neuron in a peripheral reflex arc.

• proto-oncogene a gene that can mutate to become an oncogene.

• protopathic see protopathic sensibility, protopathic itch.

• Protophormia terraenovae one of the primary flies in cutaneous myiasis.

• protoplasm [pro′to-plaz- m] the viscid, translucent colloid material, the essential constituent of the living cell, including cytoplasm and nucleoplasm.

• protoplast [pro′to-plast] a bacterial or plant cell deprived of its rigid wall but with its plasma membrane intact; the cell is dependent for its integrity on an isotonic or hypertonic medium. In bacteria, specifically refers to gram-positive organisms. See also spheroplast.

• protoplatelet [pro′to-plāt′l t] a stage in the maturation and release of platelets by megakaryocytes consisting of a strip of platelets in the peripheral circulation, which will eventually separate into individual platelets. See also proplatelet.

• protoporphyrin [pro″to-por′f -rin] a porphyrin whose iron complex united with protein occurs in hemoglobin, myoglobin, and certain respiratory pigments.

  • p. III combines with 4 moles of iron to form the heme moiety of hemoglobin.

• protoporphyrinogen III [pro″to-por″f -rin′-j n] a two carboxyl porphyrinogen, precursor of protoporphyrin III.

• protoporphyrinogen oxidase the enzyme catalyzing the oxidative O2-dependent aromatization of protoporphyrinogen IX to the highly conjugated protoporphyrin IX, which constitutes the final reaction of the common branch of the heme as well as the chlorophyll biosynthesis pathway. It is the target of diphenyl ether-type herbicides.

• protoporphyrinuria [pro″to-por″f -rľ-nu′re-] protoporphyrin in the urine.

• Protospirura [pro″to-spi-roo′r ] a genus of spirurid nematodes in the family Spiruridae.

  • P. muris, P. muricola, P. numidia found in the stomach of various felids and rodents.

• Protostrongylus [pro″to-stron′j -l s] a genus of hair-like lungworms found in the bronchioles, alveoli, and parenchyma of the lungs of some mammals.

  • P. boughtoni, P. sylvilagi in cottontail rabbits and hares.
  • P. brevispiculum, P. davtiani, P. hobmaieri, P. rushi, P. stilesi in bighorn sheep.
  • P. kochi, P. skrajabini in sheep and goats.
  • P. oryctolagi in rabbits.
  • P. pulmonalis in rabbit and hare.
  • P. rufescens found in sheep, goats, and deer.
  • P. tauricus found in hares.

• Prototheca [pro″to-the′k ] a genus of achloric algae, possibly a mutant form of Chlorella. They are saprophytic organisms that usually occupy freeliving niches in a great variety of places. Very rarely infection may occur in canine and feline skin, bovine mammary gland, canine eye, and the canine colon. Systemic infections also occur. Species involved include P. stagnora, P. trispora, P. wickerhami, and P. zopfii. See also protothecal enterocolitis.

• protothecosis [pro″to-the-ko′sis] granulomatous panuveitis, enterocolitis, mastitis, dermatitis or a systemic spread of infection with the achlorophyllous algae Prototheca. Prototheca zopfii is typically associated with gastrointestinal and disseminated disease in young dogs, and Prototheca wickerhamii with cutaneous infections in dogs and cats.

• prototroph [pro′to-trōf] an organism with the same growth factor requirements as the ancestral strain; said of microbial mutants.

• prototype [pro′to-tīp] the original type or form that is typical of later individuals or species.

• protoveratrine [pro″to-ver′ -trēn] one of the poisons found in the members of the plant genus Veratrum. Causes salivation, purgation, vomiting, diuresis, excitement, prostration, convulsions, and cardiac arrhythmia.

• Protozoa [pro″to-zo′ ] a phylum comprising the unicellular eukaryotic organisms; most are freeliving, but some lead commensalistic, mutualistic, saprophytic or parasitic existences. Groups of veterinary interest include apicomplexans, flagellates, and amebae. Pathogenic protozoa of animals include: Acanthamoeba, Babesia, Balantidium, Besnoitia, Chilomastix, Cochlosoma, Cryptobia, Cryptosporidium, Cystoisospora, Dientamoeba, Eimeria, Encephalitozoon, Endolimax, Entamoeba, Frenkelia, Giardia, Haemoproteus, Hammondia, Hartmannella, Hepatozoon, Hexamita, Histomonas, Iodamoeba, Isospora, Klossiella, Leishmania, Leucocytozoon, Naegleria, Parahistomonas, Pentatrichomonas, Plasmodium, Sarcocystis, Theileria, Toxoplasma, Trichomonas, Tritrichomonas, Trypanosoma, Tyzzeria, and Wenyonella spp.

• protozoacide [pro″to-zo′ -sīd] destructive to protozoa; an agent destructive to protozoa.

• protozoal [pro″to-zo′ l] pertaining to or caused by protozoa.

  • p. myeloencephalitis see equine protozoal myeloencephalitis.
  • p. hepatitis caused usually by Toxoplasma, Neospora, Leishmania. Rare cases of hepatic coccidiosis are observed but the causative organisms are not identified.

• protozoan [pro″to-zo′ n] 1. of or pertaining to protozoa. 2. an organism belonging to the Protozoa.

• protozoology [pro″to-zo-ol′ -je] the scientific study of protozoa.

• protozoon [pro″to-zo′on] pl. protozoa [Gr.] any member of the Protozoa.

• protozoophage [pro″to-zo′o-fāj] a cell having the ability to phagocytose protozoa; also known as a cytophage.

• protractor [pro-trak′t r] an instrument for extracting foreign bodies from wounds.

• protransglutaminase [pro-tranz″gloo-tam′ľ-nās] the inactive precursor (zymogen) of transglutaminase; called also coagulation factor XIII (fibrin stabilizing factor) in the blood coagulation system.

• protriptyline a tricyclic antidepressant.

• protrusion [pro-troo′zh n] extension beyond the usual limits, or above a plane surface.

• protuberance [pro-too′b r- ns] a projecting part, or prominence.

• external occipital p. on the occipital surface of the occipital bone, above the foramen magnum. The ligamentum nuchae is attached to it.

• intercornual p. the prominence between the horns of cows.

• protuberantia [pro-too″b r-an′sh] pl. protuberantiae [L.] protuberance.

• protyrosinase [pro-ti-ro′sin-ās] precursor of tyrosinase, an enzyme critical in the formation of melanin.

• proud exuberant.

  • p. cut see cut proud.
  • p. flesh see proud flesh.

• proven sire a sire whose genetic credentials have been established by the production performances of his offspring in a properly conducted progeny test.

• proventricular [pro″v n-trik′u-l r] pertaining to or emanating from the proventriculus.

  • p. dilatation disease a progressive weight loss associated with atony of the crop and proventriculus and atrophy of the gizzard, a nonsuppurative encephalitis, and visceral ganglioneuritis; caused by avian bornavirus. Called also macaw wasting disease, infiltrative splanchnic neuropathy, and avian ganglioneuritis.

• proventriculitis [pro″v n-trik″u-li′tis] inflammation of the proventriculus, generally referring to the avian.

• proventriculotomy [pro″v n-trik″u-lot′ -me] incision of the proventriculus; usually for the removal of ingested foreign bodies.

• proventriculus [pro″v n-trik′u-l s] the elongated, spindle-shaped, glandular stomach of birds. Supplemented by the muscular stomach just distal (aboral) to it.

• Providencia [prov″ľ-den′sh ] a genus of gram-negative, non–lactosefermenting, urease producing rod-shaped bacteria within the family Enterobacteriaceae. Occasionally isolated from diseased animals. May cause diarrhea and opportunistic infections in dogs and a relatively common cause of disease in reptiles.

  • P. stuartii once suspected as a cause of severe enteritis in newborn calves.

• provings [prōōv′ings] in homeopathy, the testing of repeated doses of plants substances in healthy individuals.

• provirus [pro-vi′r s] the genome of a retrovirus integrated into the chromosome of the host cell, and thus replicated to all of its progeny cells.

• provitamin [pro-vi′t -min] a substance, e.g., ergosterol, from which the animal organism can form a vitamin.

  • p. A see carotene.

• proximad [prok′sľ-mad] in a proximal direction; proximally.

• proximal [prok′sľ-m l] nearest to a point of reference, as to a center or median line or to the point of attachment or origin.

• proximalis [prok″sľ-ma′lis] [L.] proximal.

• proximate [prok′sľ-m t] immediate; nearest.

• proximobuccal [prok″sľ-mo-buk′ l] pertaining to the proximal and buccal surfaces of a posterior tooth.

• proxymetacaine see proparacaine.

• prozone [pro′zōn] the phenomenon exhibited by some sera, in which agglutination or precipitation occurs at higher dilution ranges, but is inhibited and not visible at lower dilutions or when undiluted.

• PRPP phosphoribosylpyrophosphate.

• PRRS porcine reproductive and respiratory syndrome.

• PRSL protein renal solute load.

• prucalopride a highly selective 5-hydroxytryptamine (5-HT4) agonist; stimulates gastric contractions in dogs and colonic motility in dogs and cats. Not currently approved for use in the US. See also metoclopramide, cisapride.

• prulaurasin a cyanogenetic glycoside found in the seeds, and to a less extent foliage, of plants in the family Rosaceae.

• prunasin a cyanogenetic glycoside found in the seeds, and to a less extent in the foliage, of plants of the Rosaceae family.

• Prunus [proo′n s] a genus of trees in the family Rosaceae. The leaves and seeds of these trees contain cyanogenetic glycosides that are potentially poisonous. The fruit pulp appears to quite safe. The glycosides are amygdalin, prunasin, prulaurasin. The following are the known toxic plants—P. amygdalus var. amara seeds (bitter almond), P. armeniaca (apricot), P. brachybotrya, P. caroliniana, P. laurocerasus (cherry laurel), P. cerasus (cherry), P. domestica (plum), P. padus (bird cherry), P. pennsylvanica (pincherry), P. persica (peach), P. sellowii, P. serotina (wild black cherry), P. sphaerocarpa, P. virginiana (chokecherry), P. virginiana var. demissa (western chokecherry), P. virginiana var. melanocarpa (western chokecherry).

  P-79.

  

  Przewalski’s horse

• pruritogenic [proo″rit-o-jen′ik] causing pruritus or itching.

• pruritus [proo-ri′t s] medical term for ‘itch’; behaviors in animals that are compatible with ‘itch’ are rubbing, licking, rolling, headshaking (ear pruritus), and/or scratching. Pruritus is epidermal in origin and does not occur in deep ulcerations, although they may be painful. It is most intense at mucocutaneous junctions. See also paresthesia, hyperesthesia.

  • p. ani pruritus of the perianal area; in dogs and cats the most common causes are due to allergic skin disease and anal sac disease.
  • cholinergic p. caused by stimulation of afferent cholinergic fibers at the neuroglandular junction of the sweat gland with release of acetylcholine and sweat. There is mast cell degranulation. Called also heat reflex urticaria.

• Prussian blue ferric ferrocyanide; a dark blue dye, used to demonstrate ferric iron in tissue sections and in the treatment of chronic thallium poisoning.

• prussic acid [prus′ik] see cyanide.

• PRV pseudorabies virus.

• Przevalskiana a parasitic fly of the family Oestridae with a life cycle resembling that of Hypoderma spp. Parasitizes goats, sheep, gazelle.

• Przewalski’s horse a primitive dun-colored pony with a dark dorsal stripe and zebra markings on the legs, 12.1–14 hands high. Equus ferus przewalski, an endangered species. Called also Mongolian wild horse.

• psammoma bodies laminated round aggregates of calcium that resemble sand. Seen in the meninges, choroid plexus, and some tumors. See corpora arenacea.

• psammomas [sam-o′m s] bodies that occur in meningiomas. They are calcified material within the center of a laminated whorl of elongated fibroblastic cells. See also acervuli, corpora arenacea, and psammoma bodies.

• psammomatous [sam-o′m -t s] pertaining to a psammoma.

  • p. meningioma a meningioma in which psammoma bodies occur.

• psammosarcoma a sarcoma containing granular material.

• Psathyrotes annua North American plant in the family Asteraceae; a highly poisonous plant causing acute or chronic hepatic injury caused by an unidentified hepatotoxin. Death may occur in as little as 24 hours. Chronic cases develop jaundice. Called also psathyrotes desert velvet, mealy rosettes.

• PSCID primary severe combined immunodeficiency disease. See com-bined immune deficiency syndrome.

• PSE 1. pale soft exudative pork. 2. portosystemic encephalopathy.

• Pseudallescheria boydii [sōōd″al- s-kēr′e-] now classified as Scedosporium apiospermum or S. boydii.

• pseudallescheriosis [sōōd″ l-es-k -ri′o-sis] infection with Pseudallescheriaboydii (syn. Petriellidium boydii, Allescheria boydii). See eumycotic mycetoma.

• Pseudamphistomum [sōōd″am-fis′to-m m] a digenetic trematode, parasitic in the liver, of the family Opisthorchiidae.

  • P. truncatum occurs in carnivores and humans and has a life cycle and pathogenicity similar to those of Opisthorchis spp.

• pseudarthrosis, pseudoarthrosis [sōōd″ahr-thro′sis] a pathological entity characterized by a nonosseous union of bone fragments of a fractured bone due to inadequate immobilization leading to existence of the ‘false joint’ that gives the condition its name.

• Pseudaspidodera a genus of roundworms in the family Heterakidae.

  • P. jnanendre, P. pavonis found in the cecum of peafowl. Do not appear to be pathogenic.

• pseud(o)- word element. [Gr.] false; deceptive resemblance.

• pseudoachondrodysplasia a congenital skeletal disorder; inherited as an autosomal recessive trait in Miniature poodles and Scottish deerhounds, evident from a very early age. There are short limbs and a normal size head,

• pseudoachondroplastic dysplasia [sōō″do-a-kon″dro-plas′tik dis-pla′ zh ] see epiphyseal dysplasia.

• pseudoalbinism [sōō″do-al′bľ-niz- m] a defect of pigmentation similar to albinism. Most suspected cases of albinism in animals are of pseudoalbinism with pigment in some places, e.g., the eyes. Many equine pseudoalbinos die in utero or have a congenital absence of a gut segment. See also Chediak–Higashi syndrome.

  • flatfish p. abnormal pigmentation in juvenile flatfish. The etiology of this condition has not been confirmed but is thought to occur during metamorphosis.

• pseudoalbino see albino.

• pseudoallele [soo″do- -lēl′] two or more genes with similar functions that are genetically linked; located so close to one another on a chromosome that the two (or more) genes are nearly always inherited together. Since their functions are related, the genes may appear to act as a single gene; however, the genes can rarely be separated, during recombination.

• pseudoanemia [soo″do- -ne′me-] marked pallor with no evidence of anemia.

• pseudoaneurysm [soo″do-an′u-riz- m] false aneurysm; differs from a true aneurysm in that its wall does not contain the components of an artery, but consists of fibrous tissue, which usually continues to enlarge, creating a pulsating hematoma.

• pseudoankylosis [soo″do-ang″k -lo′sis] a false ankylosis.

• pseudoanodontia [soo″do-an″o-don′sh ] failed eruption rather than absence of teeth. Occurs in gray lethal mice and in Lhasa apso and Shih tzu dogs. See also anodontia.

• Pseudobilharziella a genus of blood flukes in the family Schistosomatidae. Found in the blood vessels of some anatid birds.

• pseudoblackleg [soo″do-blak′leg] a disease of cattle caused by Clostridium septicum and resembling blackleg clinically but occurring only when precipitated by trauma such as shearing wounds. The disease occurs also in pigs but is a systemic infection by C. septicum with a primary lesion in the stomach.

• pseudobulbar [soo″do-bul′b r] apparently, but not really, due to a lesion of the medulla oblongata.

• Pseudocalymma elegans South American plant in the family Bignoniaceae; contains monofluoroacetate that causes staggering, tremor and convulsions followed by death in ruminants and horses, all within a few hours. Called also Arrabidaea elegans.

• Pseudocaranx a genus offinfish in the familyCarangidae. IncludesP. dentex, commonly called white trevally and P. georgianus (silver trevally).

• pseudocarcinomatous hyperplasia [soo″do-kahr″sľ-nom′ -ts hi″pr-pla ′zh] adnexal epithelial hyperplasia in the skin whose deep epidermal down-growths resembles a squamous cell carcinoma. Usually secondary to chronic dermal inflammation or irritation.

• pseudocartilaginous [soo″do-kahr″tľ-laj′ľ-n s] resembling cartilage.

• pseudocast [soo′do-kast] an accidental formation of urinary sediment resembling a true cast.

• pseudocervix [soo′do-sur′viks] false or phantom cervix created during examination of the canine reproductive tract, when the dorsomedial fold of the vagina and the lateral walls of the vagina cause a temporary obstruction.

• pseudocholinesterase [soo″do-ko″lin-es′t r-ās] see butyrylcholinesterase.

• pseudochorea [soo″do-k -re′] a state of general incoordination resembling chorea.

• pseudochylothorax [soo″do-ki″lo-tho′raks] see chyloid effusion.

• pseudochylous effusion [soo″do-ki′l s] see chyloid effusion.

• pseudocoarctation [soo″do-ko″ahrk-ta′sh n] a condition radiographically resembling coarctation but without compromise of the aortic lumen, as occurs in a congenital anomaly of the aortic arch.

• pseudocolloid [soo″do-kol′oid] a mucoid substance sometimes found in ovarian cysts.

• pseudocoloboma [soo″do-kol″o-bo′m ] a line or scar on the iris resembling a coloboma.

• pseudocontinuity [soo″do-kon″tľ-nu′ľ-te] abnormal healing and regeneration of severed nerve fibers; the space between the cut ends becomes filled with fibrous tissues rather than nerve fibers.

• pseudocoprostasis [soo″do-kop-ros′t -sis] constipation caused by matting of haircoat around the anus that impedes passage of feces. Seen in longhaired dogs and cats.

• pseudocowpox [soo″do-kou′poks] an infectious disease of the skin of teats of cows caused by a paravaccinia virus. Typical lesions commence as erythema, progress to a vesicle, pustule, or scab that is shed leaving a horseshoe-shaped ring of small scabs. Persons milking the cows may develop lesions on their hands. Called also milker’s nodule.

• pseudocoxalgia [soo″do-kok-sal′j ] 1. osteochondrosis of the capitular epiphysis of the femur. 2. Legg–Calvé–Perthes disease.

• pseudocrisis [soo′do-kri″sis] sudden but temporary abatement of febrile signs.

• pseudo-Cushing’s syndrome see alopecia X.

• pseudocyesis [soo″do-si-e′sis] see false pregnancy.

• pseudocylindroid [soo″do-s -lin′droid] a shred of mucin in the urine resembling a cylindroid.

• pseudocyst [soo′do-sist] an abnormal dilated space resembling a cyst but not lined with epithelium, e.g., a retroperitoneal accumulation of urine from a leaking ureter.

  • pancreatic p. accumulation of pancreatic secretions and cellular debris may occur with recurring episodes of pancreatitis, most commonly in dogs.
  • perirenal p., perinephritic p. see feline perirenal cysts.
  • salivary p. see salivary mucocele.

• pseudodiabetes old term used to describe early or transient diabetes mellitus, including hyperglycemia due to insulin resistance from concurrent disease. See also prediabetes.

  • azotemic p. a glucose intolerance seen in association with azotemia, thought to be due to a peripheral resistance to insulin-mediated uptake of glucose by tissues. Severe hyperglycemia, glucosuria, ketonemia, ketonuria, and metabolic acidosis are not features.

• Pseudodiscus a genus of intestinal flukes (digenetic trematodes) in the family Paramphistomatidae.

  • P. collinsi found in the colon of horses.

• pseudodistemper [soo″do-dis-tem′p r] tyrosinemia in mink.

• pseudodominant [soo″do-dom′ľ-n nt] the phenotypic expression of a recessive allele as the result of losing the dominant allele, either via deletion or genetic imprinting, or only having one allele, as in the case of genes carried on the single X chromosome in mammalian males.

• pseudoedema [soo″do- -de′m] a puffy state resembling edema.

• pseudoemphysema [soo″do-em″fľ-ze′m ] a condition resembling emphysema, but due to temporary obstruction of the bronchi.

• pseudoenophthalmos [soo″do-en″of-thal′mos] apparent enophthalmos, resulting from a small globe (phthisis or microphthalmos) or swollen eyelids.

• pseudo-eosinophil [soo″do-e″o-sin′o-fil] the heterophil of rabbits and guinea pigs with prominent granules.

• pseudoephedrine [soo″do- -fed′rin] one of the isomers of ephedrine.

• pseudoepitheliomatous hyperplasia [soo″do-ep″ľ-the″le-o′m -ts hi″ pr-pla′zh] hyperkeratosis resembling an epithelioma.

• pseudoexstrophy [soo″do-ek′str -fe] a developmental anomaly marked by the characteristic musculoskeletal defects of exstrophy of the bladder, but with no major defect of the urinary tract.

• pseudofarcy [soo′do-fahr″se] see epizootic lymphangitis.

• pseudofilling defects [soo′do-fil′ing] the false impression of a filling defect within an organ on imaging. May be seen for example within the heart on CT angiography due to vascular stasis.

• pseudo-fowl pest see Newcastle disease.

• pseudofracture [soo″do-frak′ch r] radiological appearance of a thickened periosteum and new bone formation over what looks like an incomplete fracture. Seen in osteomalacia.

• Pseudogaltonia clavata South African plant in the family Liliaceae; contains a cardiac glycoside thought to cause cardiac irregularity, sudden death; called also P. pechuelli, P. subspicata, Lidneria clavata, cape hyacinth, Southwest African slangkop.

• pseudoganglion [soo″do-gan˙gli˙on] an enlargement on a nerve resembling a ganglion.

• pseudogene [soo″do-jēn] a gene copy that carries a mutation in the coding sequence that renders it non-functional (e.g., frameshift, premature stop codon) but that resembles a functional gene.

• pseudoglanders [soo″do-glan′d rz] see epizootic lymphangitis. See also melioidosis.

• pseudoglandular [soo″do-glan′du-l r] with some of the characteristics of a gland.

• pseudoglottis [soo″do-glot′is] the aperture between the false vocal cords.

• pseudogout [soo′do-gout] synovial deposition of calcium phosphate crystals has been described as a rare cause of arthritis in dogs.

• pseudohematuria [soo″do-he″m -tu′re-] the presence in the urine of pigments that impart a pink or red color, but with no detectable hemoglobin or blood cells.

• pseudohemophilia [soo″do-he″mo-fil′e- ] von Willebrand disease.

• pseudohepatorenal syndrome [soo″do-hep″ -to-re′n l] many disease states in which there are clinical indications of renal and hepatic disease but there is no relationship between the two, e.g., a systemic disease in which the agent causes both hepatic and renal damage.

• pseudohermaphrodite [soo″do-h r-maf′ro-dīt] an individual exhibiting pseudohermaphroditism.

• pseudohermaphroditism [soo″do-h r-maf′ro-dit-iz″ m] a state in which the gonads are of one sex but one or more contradictions exist in the morphological criteria of sex. In female pseudohermaphroditism, the individual is a genetic and gonadal female with partial masculinization; in male pseudohermaphroditism, the individual is a genetic and gonadal male with incomplete masculinization. Pseudohermaphroditism is not to be confused with hermaphroditism, in which the individual possesses both ovarian and testicular tissue.

• pseudohernia [soo″do-hur′ne- ] an inflamed sac or gland simulating strangulated hernia.

  • p. inguinalis a mass of cod fat that distends the scrotum and dilates the inguinal canal.

• pseudohyperkalemia [soo″do-hi″p r-k-le′me-] artifactual elevations of serum potassium concentration can be caused by an increased release from platelets during clotting of the sample, delayed separation of serum and cells, hemolysis (especially in horses, cattle, and pigs), extreme leucocytosis, or use of potassium EDTA.

• pseudohyperparathyroidism [soo″do-hi″p r-par″-thi′roid-iz- m] persistent hypercalcemia and hypophosphatemia, due to ectopic secretion of parathyroid hormone (-like) polypeptides or other bone resorbing substances by neoplasms. Lymphosarcoma and apocrine adenocarcinoma of the anal sac in dogs are common source. Nephrocalcinosis can also occur. The clinical and biochemical abnormalities are reversed if the tumor is removed. See also hyperparathyroidism.

• pseudohypertrophy [soo″do-hi-pur′tr -fe] increase in size without true hypertrophy.

• pseudohypha [soo″do-hi′f ] pl. pseudohyphae a chain of blastoconidia.

• pseudohypoaldosteronism [soo″do-hi″po-al-dos′t r-ōn-iz- m] lack of responsiveness of end organs to aldosterone. In humans two forms recognized: renal form with autosomal dominant inheritance exhibiting salt loss mainly from the kidneys, and multi-system form with autosomal recessive form exhibiting salt loss from kidney, lung, and sweat and salivary glands.

• pseudohyponatremia [soo″do-hi″po-n -tre′me-] a condition in which marked increases in concentration of proteins or lipids in plasma or serum decrease the concentration of sodium measured in plasma or serum. Sodium is dissolved in plasma water but not in protein or lipid, and the concentration of sodium can be normal in plasma water but low when expressed per unit of plasma or serum, which is composed of the volume of water plus the volumes of protein and/or lipid.

• pseudohypoparathyroidism [soo″do-hi″po-par″ -thi′roi-diz- m] a condition in which there are changes characteristic of hypoparathyroidism (hypocalcemia and hyperphosphatemia) in association with hyperactive parathyroid glands and increased blood concentrations of parathyroid hormone. It is the result of nonresponsive target cells in bone and kidneys. Not reported in animals.

• pseudojaundice [soo″do-jawn′dis] yellowness of the skin not caused by liver disease.

• pseudojervine one of the toxic alkaloids in Veratrum spp. Causes vomiting, purgation, salivation, diuresis, convulsions, and death.

• pseudokidney [soo″do-kid′ne] in ultrasonography, a contracted stomach or an intussuscepted bowel can be mistaken as a kidney.

• Pseudoletia separata caterpillars that appear in massive waves and completely devour crops and pasture. Plants such as kikuyu grass are reputed to be more toxic when they regrow after such decimation. Called also army caterpillars.

• pseudoleukemia [soo″do-loo-ke′me- ] the condition in which there are excessive numbers of lymphocytes in tissues but not in blood. See also leukosis. Called also aleukemic leukemia.

• pseudolipidosis [soo″do-lip″ľ-do′sis] the original name for mannosidosis. Called also pseudolipidosis with neuronopathy.

• pseudolymphoma [soo″do-lim-fo′m ] lesions likely to be mistaken for lymphoma. Can include nodular lymphocytic–plasmacytic lesions of panniculitis, vasculitis, perifolliculitis, nodules created by vaccinations, arthropod stings.

• Pseudolynchia [soo″do-linch′e- ] a genus of biting flies in the family Hippoboscidae, parasites of birds.

  • P. canariensis pigeon louse fly, found on domestic pigeons and some wild pigeons and doves. Dark brown flies resembling a sheep ked. Intermediate host for Haemoproteus columbae, pigeon malaria organism.

• pseudomalleus [soo″do-mal′e- s] see melioidosis.

• pseudomelanosis [soo″do-mel″ -no′sis] grey to black discoloration of tissues post-mortem due to the breakdown of hemoglobin to form iron sulfide. A common post-mortem artifact.

• pseudomembrane [soo″do-mem′brān] a layer of coagulated fibrin, leukocytes, and bacteria overlying an ulcerated mucous membrane and giving the appearance of being a viable tissue. Called also false membrane.

• pseudomembranous [soo″do-mem′br -n s] pertaining to or emanating from pseudomembrane.

  • p. colitis see pseudomembranous colitis.

• Pseudomicrodochium suttonii a mold in the phylum Ascomycota associated with phaeohyphomycosis in dogs.

• Pseudomonas [soo″do-mo′n s] a genus of gram-negative, strictly aerobic bacteria in the family Pseudomonadaceae; some species in the genus are pathogenic for plants or vertebrates.

  • P. aeruginosa a common isolate from wounds, burns, and urinary tract infections, and from many other accumulations of pus in all species. Also commonly found in otitis externa, fleece rot in sheep, and some cases of bovine mastitis. Its presence may be indicated by a distinctive blue or green color of the pus or infected site, a result of the pigment pyocyanin produced by this organism.
  • P. fluorescens a common cause of food spoilage and a frequent isolate from wounds and other contaminated sites in animals.
  • P. mallei now classified as Burkholderia mallei.
  • P. pseudomallei now classified as Burkholderia pseudomallei.
  • P. putida causes septicemia in aquarium fish.

• pseudomucin [soo″do-mu′sin] a mucin-like substance found in ovarian cysts.

• pseudomucinous [soo″do-mu′sľ-n s] pertaining to pseudomucin.

  • p. cystadenoma an ovarian tumor originating from the celomic epithelium of the ovary. Most often seen in aged nulliparous bitches.

• pseudomycetoma [soo″do-mi″s -to′m] a granulomatous reaction in which dermatophilic fungi form hyphae in the dermal and subcutaneous tissues.

  • bacterial p. see botryomycosis.

• pseudomyotonia [soo″do-mi″o-to′ne- ] abnormal muscle contraction, stiffness, and pain rarely accompanying canine Cushing’s syndrome and some primary muscle disorders that can resemble myotonia, clinically and on electromyography.

• pseudomyxoma [soo″do-mik-so′m ] a mass of epithelial mucus resembling a myxoma.

  • p. peritonei the presence in the peritoneal cavity of mucoid material from a ruptured ovarian cyst or a ruptured mucocele.

• pseudoneoplasm [soo″do-ne′o-plaz- m] cutaneous lumps and masses that are not neoplastic; includes cysts, nevi, keratoses, granulomas, and pyogranulomas.

• pseudoneutropenia [soo″do-noo″tro-pe′ne- ] a large proportion of neutrophils are in the marginal pool.

• pseudo-odontoma tooth root hyperplasia. Seen in Prairie dogs.

• pseudo-oligodontia [soo″do-ol″ľ-go-don′sh ] the appearance of having less than the correct number of teeth erupted; due to failure of eruption of formed teeth. See also oligodontia.

• pseudopapilledema [soo″do-pap″il- -de′m] large optic disc mimicking papilledema but typically due to abundant myelination in the dog.

• pseudoparalysis [soo″do-p -ral′i-sis] apparent loss of muscular power without real paralysis.

• Pseudopezzia medicaginis a leaf-spotting organism that causes a manifold increase in the concentration of coumestrol in the leaves of alfalfa (lucerne).

• pseudophyllidean [soo″do-fi-lid′e- n] pertaining to tapeworms (cestodes) of the order Pseudophyllidea. Now replaced by two orders: Diphyllobothriidea and Bothriocephalidea. Members within this order usually have a three-host aquatic life cycle. Adult tapeworms are parasitic in the intestines of fish-eating mammals, birds, fish, and humans. Lengths of the adults range from 10 to 100 feet.

• pseudoplague [soo″do-plāg] see Newcastle disease.

• pseudopocket see periodontal pseudopocket.

• pseudopodium [soo″do-po′de- m] a temporary protrusion of the cytoplasm of an ameba or other motile simple cell, serving for purposes of locomotion or to engulf food.

• pseudopolycoria [soo″do-pol″e-kor′e- ] full-thickness holes in the iris giving the appearance of multiple pupils but lacking a sphincter muscle. See polycoria.

• pseudopolyodontia [soo″do-pol″e-o-don′sh ] retention of the deciduous teeth until the permanent teeth have erupted, giving the impression of more than the normal number of teeth. See also polyodontia.

• pseudopolyp [soo″do-pol′ip] a hypertrophied tab of mucous membrane resembling a polyp, but caused by ulceration surrounding intact mucosa.

• pseudopolyposis [soo″do-pol″ľ-po′sis] numerous pseudopolyps in the colon and rectum, due to longstanding inflammation.

• pseudopregnancy [soo″do-preg′n n-se] see false pregnancy.

• pseudoproptosis [soo″do-prop-to′sis] apparent exophthalmos due to buphthalmos or marked retraction of the eyelids.

• pseudoglioma [soo″do-gli-o′m ] any condition mimicking retinoblastoma, e.g., retrolental fibroplasia or exudative retinopathy. Not reported in domestic species.

• pseudopseudohypoparathyroidism [soo″do-soo″do-hi″po-par″ -thi′roidiz- m] an incomplete form of pseudohypoparathyroidism, marked by the same constitutional features but by normal concentrations of calcium and phosphorus in the blood serum.

• pseudopterygium [soo″do-t r-ij′e- m] 1. an adhesion of the conjunctiva to the cornea following inflammation or injury. 2. a term applied to a condition unique to rabbits in which there is a progressive ingrowth of bulbar conjunctival over, but not adherent to, the corneal surface. Acollagen dysplasia has been proposed as the cause. Surgical correction using a modified Arlt procedure is possible. Called also corneal occlusion syndrome, conjunctival centripetalization, and epicorneal membrane.

• pseudoptosis [soo″dop-to′sis, soo″do-to′sis] decrease in the size of the palpebral aperture but not resulting from ptosis.

• pseudoptyalism [soo″do-ti′ -liz- m] the dribbling of saliva caused by a difficulty in swallowing or paralysis of the lips.

• pseudorabies [soo″do-ra′bēz] see Aujeszky’s disease.

• pseudoreaction [soo″do-re-ak′sh n] a false or deceptive reaction; in intradermal skin tests, a reaction not due to the specific test substance but to protein or other substance in the medium employed in producing the material injected.

• pseudorickets [soo″do-rik′ ts] see renal secondary hyperparathyroidism.

• pseudorinderpest [soo″do-rin′d r-pest] see peste des petits ruminants.

• pseudoscorpion see scorpion.

• Pseudostertagia bullosa a nematode in the family Trichostrongylidae found in the abomasum of sheep, bighorn and Barbary sheep, and pronghorn antelope.

• Pseudoterranova a genus of nematodes belonging to the family Anisakidae. All hosts are marine with marine mammals as definitive hosts and teleost fishes as intermediate hosts. Includes the former genus Phocanema.

  • P. decipiens, formerly called Phocanema decipiens, the ‘cod-worm’. Adults occur in the stomachs of seals and sea-lions with intermediated stages primarily in cod. Can cause disease in humans in the larval stages are ingested in raw or undercooked fish.

• pseudotetanus [soo″do-tet′ -n s] persistent muscular contractions resembling tetanus but not associated with infection and intoxication by Clostridium tetani.

• pseudotrismus [soo″do-tris′m s] inability to completely open the mouth due to causes other than muscular spasm, e.g., in masticatory myositis of dogs.

• pseudotruncus arteriosus [soo″do-trung′k s ahr-tēr″e-o′s s] the most severe form of tetralogy of Fallot with specific pulmonary valve and/or pulmonary arterial hypoplasia or atresia.

• pseudotuberculosis [soo″do-too-bur″ku-lo′sis] resembles tuberculosis. See also yersiniosis.

  • avian p. contagious disease of birds, both domestic and wild, caused by Yersinia pseudotuberculosis and characterized by an initial, brief septicemia, followed by a bacteremic phase in which there is the development of multiple abscesses and granulomas as in avian tuberculosis. The disease causes major epornithics in populations of canaries, finches, cockatoos, parakeets. Called also canary cholera.
  • bovine p. see Johne’s disease.

• pseudotumor [soo″do-too′m r] phantom tumor.

  • p. cerebri cerebral edema and raised intracranial pressure without neurological signs except occasional sixth cranial nerve palsy.

• pseudotype phenotypic mixing within a virus family (retroviruses), or between virus family (retrovirus and rhabdoviridae) results in a genome from a parent with a defective envelope, contained within the envelope capsid from a helper virus.

• pseudoulcer ulcer-shaped defects seen in the mucosa of the small intestine due to the presence of lymphoid tissue. Seen on radiographs of dogs following contrast studies. A change of no significance. Not seen in cats.

• pseudouremia [soo″do-u-re′me- ] see azotemia.

• pseudourticaria [soo″do-ur″tľ-kar′e- ] see lumpy skin disease.

• PSGAG polysulfated glycosaminoglycan.

• psi 1. the 23rd letter of the Greek alphabet, Ψ or ψ. 2. pounds per square inch, equivalent to one-seventh of a kilopascal (kPa), the metric measure of pressure.

• Psilocaulon genus of South African plants in the family Aizoaceae; have high content of soluble oxalates; cause oxalate poisoning manifested by nephrosis, uremia, and urolithiasis. Also contain toxin psilocauline; includes P. absimile, P. rogersiae. Called also asbos, loogbos, prena vygie, asbosvygie.

• Psilocybe [si″lo-si′be] genus of toxic mushrooms in the phylum Basidiomycota; contain an indole alkaloid that causes incoordination, tremor, stumbling, recumbency, and hypersensitivity. Includes P. cubensis and P. semilanceata. Called also mad or magic mushrooms.

• psilocybin [si″lo-si′bin] a water soluble alkaloid and hallucinogen, isolated from the mushroom Psilocybe mexicana.

• psilostomatid a member of the digenetic trematode family Psilostomatidae, small, globose flukes.

• Psilostrophe NorthAmerican plant genus in the family Asteraceae; contains an unidentified toxin that causes incoordination, coughing, vomiting, emaciation, and death. Includes P. gnaphalodes, P. sparsiflora, P. tagetina. Called also paper flowers.

• psittaciform [sit′ -si-form] a bird member of the order Psittaciformes, the parrots and parakeets.

• psittacine [sit′ -sīn] said of birds that are members of the order Psittaciformes, the parrots and parakeets.

  • p. beak and feather disease occurs predominantly in young birds with their first contour feathers, but sometimes adults with previously normal feathers. There is a loss of contour and down feathers over most of the body, often progressing to complete baldness. The upper and lower beak may also be involved with inflammation, abnormal elongation, uneven wearing, and transverse fracture lines. The disease is caused by Circovirus.

• psittacosis [sit″ -ko′sis] chlamidiosis. A disease of birds caused by Chlamydia psittaci and also the zoonotic disease caused by infection with this species; first seen in parrots and later found in other birds and domestic fowl, in which it is called ornithosis. It is transmissible to humans. In birds, psittacosis is a systemic infection and signs include diarrhea and ocular and nasal discharge. Avian chlamydiosis is a disease notifiable to the OIE (see Table 20).

  P-80.

  

  Psittacine beak and feather disease in a sulfur crested cockatoo

  • p.–lymphogranuloma venereum group the family Chlamydiaceae of organisms.

• psoas [so′as] a sublumbar muscle. See Table 12.

  • p. tubercle a knob on the ventral border of the shaft of the ilium that serves as the insertion for the psoas minor muscle.

• psocid a member of the order Psocoptera of booklice.

• Psocoptera see booklice.

• psoitis [so-i′tis] inflammation of a psoas muscle or its sheath.

• Psoralea [so-ra′le- ] a genus of plants in the legume family Fabaceae; may cause primary photosensitization. Includes P. argophylla, P. tenuiflora. Called also scurf pea. See also Cullen, psoralen.

• psoralen [sor′ -l n] a furocoumarin, one of the constituents of certain plants (e.g., Psoralea corylifolia) that have the ability to produce primary photosensitization; certain perfumes and drugs (e.g., methoxsalen) contain psoralens. See also Cullen.

• Psorergates [sor″ r-ga′tēz] a genus of parasitic mites in the family Cheyletidae. Called also Psorobia spp.

  • P. bos found on cattle but there is no lesion.
  • P. oettlei (syn. P. simplex) found on laboratory mice and rats.
  • P. ovis (syn. Psorobia ovis) causes a mild pruritus and scaly dermatitis on the body of sheep with some damage to the wool. Called also itch mite.
  • P. rattus found in rats, specifically Rattus norvegicus.
  • P. simplex see P. oettlei (above).

• psorergatic mange see Psorergates ovis.

• pseudoneuritis [soo″do-n $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ -ri′tis] a congenital hyperemic condition of the optic papilla in humans.

• psoriasiform [so″re-as′ľ-form] a dermatosis resembling the human skin condition, psoriasis.

  • p.-lichenoid dermatosis multiple lichenoid, hyperkeratotic papules and plaques begin to appear in young adult English springer spaniel dogs, first on the pinnae, ear canal, and inguinal skin and later other areas.

• psoriasis [s -ri′ -sis] a usually chronic, recurrent skin disease in humans marked by discrete macules, papules, or patches covered with lamellated silvery scales resulting from an increased turnover of epidermal cells. The cause is multifactorial and poorly understood. There is no equivalent disease in animals, although the term is sometimes used for purposes of comparison, e.g., psoriasiform lichenoid dermatosis, psoriasiform epidermal hyperplasia, porcine juvenile pustular psoriasiform dermatitis (pityriasis rosea).

• Psorobia ovis [so-ro′be- ] see Psorergates ovis.

• Psorophora [s -rof′o-r] a genus of mosquitoes; a cause of severe insect worry when in large numbers and may cause deaths of poultry.

• Psoroptes [s -rop′tēz] a genus of mange mites in the family Psoroptidae. See psoroptic mange.

  • P. cervinus found on bighorn sheep, wapiti.
  • P. communis see Psoroptes ovis (below).
  • P. cuniculi found on the ears of rabbit, goat, horse, donkey, and mule.
  • P. equi found on horses. Found also on the donkey and mule.
  • P. hippotis see P. cuniculi (above).
  • P. natalensis found on the body of cattle (Bos taurus, B. indicus), Indian water buffalo.
  • P. ovis causes sheep-scab; found also on cattle and goats.

• psoroptic mange [s -rop′tik mānj] a parasitic dermatitis of many species caused by Psoroptes spp. mites. They are P. cervinus (deer), P. equi, P. natalensis (cattle and water buffalo), and P. ovis (sheep, goats, and cattle). The common ear mange mites are P. cuniculi. The disease in sheep is serious with much damage to fleece and some deaths. Goats and horses show mostly ear mange with much head shaking but lesions can occur anywhere on the body. In cattle, the lesions are widespread, and itching is severe. Called also sheep-scab, body mange, ear mange.

  P-81.

  

  Psoroptes cuniculi mites

  P-82.

  

  Psoroptic manged in the ear of a rabbit showing the typical heavy encrustations

• PSP phenolsulfonphthalein.

• PSP toxins paralytic shellfish poisoning toxins.

• PSPB pregnancy specific protein B.

• PSS 1. porcine stress syndrome. 2. portosystemic shunt.

• psychic [si′kik] pertaining to the mind or psyche. See also psychogenic.

• psych(o)- word element. [Gr.] relationship to the mind.

• psychodid a member of the family Psychodidae. The sandflies or owl midges. Includes Phlebotomus.

• psychogenic [si″ko-jen′ik] having an emotional or psychological origin; there is debate about whether it can or should be applied to animals. Nevertheless, some diseases of animals are considered by some to have a psychogenic origin, e.g., esophagogastric ulcer of pigs, despite our limited knowledge of their psychological makeup. See also psychogenic polyphagia, psychogenic polydipsia.

  • p. alopecia anxiety and excessive grooming in cats can cause loss of hair from barbering and pulling. In a more severe form, injury to the skin occurs and eosinophilic plaques may appear.
  • p. dermatitis see acral lick dermatitis, idiopathic hyperesthesia syndrome, tail biting, tail sucking, flank sucking.

• psychomotor [si″ko-mo′t r] pertaining to motor effects of cerebral or psychic activity.

  • p. epilepsy see psychomotor seizure.

• psychopathology [si″ko-p -thol′ -je] the pathology of mental disease. Currently this is not a subject dealt with in veterinary medicine.

• psychosis [si-ko′sis] pl. psychoses any major mental disorder of organic or emotional origin, marked by derangement of the personality and loss of contact with reality, often with delusions, hallucinations, or illusions. There is no scientific study of animal psychiatry and no specific psychoses but some well-identified and traumatic vices, e.g., cribbiting, weaving, tail chasing, and flank sucking in dogs, are often classified as such. Farrowing hysteria in sows seems to be the animal disease with the closest approximation to a derangement of personality.

  • parturient p. of sows see farrowing hysteria.
  • puerperal p. 1. whelping bitches sometimes display frenzied, destructive behavior and aggression. 2. sows. See farrowing hysteria.

• psychosomatic [si″ko-so-mat′ik] pertaining to the interrelations of mind and body; having bodily clinical signs of psychic, emotional or mental origin.

• psychosurgery [si″ko-sur′j r-e] neurosurgery for the purpose of altering behavior. See olfactory tractotomy.

• Psychotria a South American plant genus of the family Rubiaceae whose root contains emetine, a powerful emetic isoquinoline alkaloid, which is the active ingredient of syrup of ipecac. Poisoning may occur and is manifested by persistent, violent vomiting. Includes P. ipecacuanha (Cephaelis ipecacuanha), P. acuminata (Cephaelis acuminata). Called also ipecac, ipecacuanha.

• psychotropic [si″ko-tro′pik] capable of modifying mental activity, and thus behavior.

  • p. drugs the important groups in veterinary medicine are the phenothiazine, butyrophenone, and benzodiazepine derivatives.

• psychr(o)- word element. [Gr.] relationship to cold.

• psychrophile [si′kro-fīl] a psychrophilic organism.

• psychrophilic [si″kro-fil′ik] fond of cold; said of bacteria that grow best in the cold (40–68°F; 5–20°C).

• psychrophore [si′kro-for] a double catheter for applying cold, per medium of cold water, to a cavity.

• psychrotherapy [si″kro-ther′ -pe] treatment of disease by applying cold. See also cryosurgery.

• psyllium [sil′e- m] a fecal softener made from the seeds of the plants Plantago psyllium, P. indica, and P. ovata. The mucilloid portion of the seeds of P. ovata is used to make psyllium hydrophilic mucilloid, which is a bulk laxative to relieve constipation caused by a low residue diet. Psyllium mucilloid is also used to treat and prevent sand colic in horses, where sand is ingested during grazing or feeding on sandy soil causing colonic irritation, altered motility, and in some cases impaction.

• PT prothrombin time.

• Pt chemical symbol, platinum.

• pt pint.

• PTA plasma thromboplastin antecedent, clotting factor XI.

• ptaquiloside a norsesquiterpene glucoside of the illudane type; also called aquilide A; a major toxic principle of brackens (Pteridium spp.) and rock fern (Cheilanthes sieberi); occurs in other ferns including Histiopteris incisa, Onychium contiguum, Pteris cretica; causes neutropenia and thrombocytopenia leading to generalized hemorrhages and septicemia in osteomyelotoxic ptaquiloside poisoning, the so-called ‘acute’ poisoning of cattle, carcinogenic ptaquiloside poisoning (bovine enzootic hematuria), and bright blindness of sheep.

  • carcinogenic p. poisoning ptaquiloside ingestion in small doses over a long period (years) causes proliferative lesions and neoplasms in and bleeding from the urinary bladder mucosa in cattle, but no effects on bone marrow. Called also bovine enzootic hematuria. There is also a relationship between access to bracken and a higher than normal occurrence of alimentary tract carcinoma in ruminants.
  • osteomyelotoxic p. poisoning ptaquiloside ingestion in large doses by cattle over a short period (weeks) causes depression of bone marrow activity, leading to pancytopenia, evidenced principally as ecchymotic hemorrhages in mucosae and serosae, and terminal septicemia. Severe diarrhea and dysentery or pharyngeal edema may be terminal events. Erroneously called ‘acute’ bracken poisoning.
  • retinotoxic p. poisoning ptaquiloside ingestion over a long period (years) by sheep in Britain causes retinal degeneration and blindness. Called also bright blindness.

• ptarmic [tahr′mik] causing sneezing.

• ptarmus [tahr′m s] spasmodic sneezing.

• PTC plasma thromboplastin component, clotting factor IX, Christmas factor.

  P-83:

  

  Pteridium aquilinum.

• Pteridium [t -rid′e- m] a fern genus in the family Dennstadiaceae. The fern is classified by some authorities as more than one species including: P. aquilinum, P. esculentum (austral bracken), P. revolutum (hairy bracken), and the hybrid P. esculentum × P. revolutum (P. yarrabense northern bracken). Called also Pteris aquilinum, bracken. It contains ptaquiloside and a thiaminase that both poison domestic animals, and a cyanogenic glycoside that does not. Manifestations of ptaquiloside poisoning of cattle (rarely sheep) vary with dose and duration of intake; see ptaquiloside. A thiaminase in bracken causes a clinical syndrome of thiamine deficiency in horses. Signs are muscle tremor, incoordination, frequent falling, and bradycardia and cardiac irregularity.

  • pteridophyte a member of the ferns and their allies.

• Pteris aquilina Pteridiumaquilinum.

• Pteroglossus a genus of bird in the family Ramphastidae. One genera of the toucan family.

• Pterolichus a genus of mites in the family Dermoglyphidae.

  • P. bicaudatus found on the feathers of the South African ostrich.
  • P. obtusus found on the feathers of fowls.

• Pteronia pallens South African plant in the family Asteraceae; contains an unidentified toxin that damages liver and kidneys. Called also Scholtz bush, witbossie, P. geigeroides.

• Pteronyssus striatus a feather mite found on sparrow, linnet, and chaffinch.

• Pterophagus a genus of astigmatid mites in the family Falculiferdae.

  • P. strictus found on the feathers of pigeons.

• Pterophyllum the genus of small, highly colored, laterally compressed aquarium fish with thin, trailing fins. Commonly referred to as angelfish in the aquarium trade industry.

• Pteropus the genus of fruit bats or flying foxes; see also bats.

• pteroside a glycoside of pterosins.

• pterosin a sesquiterpenoid found in bracken (Pteridium aquilinum).

• pteroylglutamic acid see folic acid.

• pterygium [t -rij′e- m] a wing-like structure, especially an abnormal triangular fold of conjunctival membrane extending over the cornea in the interpalpebral fissue. Seen in primates as a result of excessive sunlight exposure.

• pterygoid [ter′ľ-goid] shaped like a wing.

  • p. bone see pterygoid bone. See also Table 9.
  • p. process see pterygoid process.

• pterygomandibular [ter″ľ-go-man-dib′u-l r] pertaining to the pterygoid process and the mandible.

• pterygomaxillary [ter″ľ-go-mak′sľ-lar-e] pertaining to a pterygoid process and the maxilla.

• pterygopalatine [ter″ľ-go-pal′ -tīn] pertaining to a pterygoid process and the palatine bone.

• pterylae [ter″ľ -le′] tracts on the skin of birds into which feathers are implanted and that establish the pattern of the plumage of that bird for that molt.

• pterylosis [ter″ľ -lo′sis] the distribution of feathers in the pterylae.

• PTFE polytetrafluoroethylene.

• PTH parathyroid hormone.

• PTH-rP parathyroid hormone-related protein.

• ptilopody [ti-lip′ -de] feathering of the foot and toes of birds.

• ptilosis [ti-lo′sis] 1. falling out of the eyelashes. 2. the feather coat, total feather covering, of birds.

• ptomaine [to′mān] any of an indefinite class of toxic bases, usually considered to be formed by the action of bacterial metabolism on proteins.

  • p. poisoning a term commonly misapplied to food poisoning. Contrary to popular belief, ptomaines are not injurious to the carnivorous or omnivorous digestive systems, which are quite capable of reducing them to harmless substances. Decomposed foods are often responsible for food poisoning, however, because they may harbor certain forms of poisonproducing bacteria, especially Clostridium botulinum.

• ptosed [tōst] affected with ptosis.

• ptosis [to′sis] 1. prolapse of an organ or part. 2. paralytic drooping of the upper eyelid. Can be a normal anatomic feature in some dog breeds with abundant facial folds.

• -ptosis word element. [Gr.] downward displacement.

• PTS put to sleep; a common euphemism for euthanasia, but can be misinterpreted as going to sleep under general anesthesia.

• PTT partial thromboplastin time.

• PTU propylthiouracil.

• ptyalagogue [ti-al′ -gog] sialagogue.

• ptyalectasis [ti″ -lek′t -sis] 1. a state of dilatation of a salivary duct. 2. surgical dilatation of a salivary duct.

• ptyalin [ti′ -lin] see amylase.

• ptyalism [ti′ -liz- m] excessive secretion of saliva; seen in rabbits, guinea pigs with malocclusion or heat stress, ruminants poisoned by Rhizoctonia leguminicola. See also hypersalivation, salivation.

• ptyal(o)- word element. [Gr.] relationship to saliva.

• ptyalocele [ti-al′o-sēl] a cystic tumor containing saliva.

• ptyalogenic [ti″ -lo-jen′ik] formed from or by the action of saliva.

• ptyalorrhea [ti″ -lo-re′] ptyalism.

• Pu chemical symbol, plutonium.

• pubertal [pu′b r-t l] pertaining to or emanating from puberty.

  • p. period the period approaching puberty when gonadal function, accessory sex gland function, and behavior develop to the point where reproduction is possible.

• puberty [pu′b r-te] the time at which reproduction by an individual animal becomes possible for the first time; a term used infrequently in veterinary medicine but there is no other word which can substitute for it.

  • delayed p. varies widely between species and between breeds; negatively influenced by undernutrition and obesity.

• pubescent [pu-bes′ nt] 1. arriving at the age of puberty. 2. covered with down or lanugo.

• pubic [pu′bik] pertaining to or lying near the pubis.

  • p. ligament see Table 11.
  • p. region the middle portion of the most caudal region of the abdomen, located caudal to the umbilical region and between the inguinal regions.
  • p. tubercle a prominent tubercle at the lateral end of the pubic crest.

• pubiotomy [pu″be-ot′ -me] surgical separation of the pubis lateral to the symphysis.

• pubis [pu′bis] pl. pubes [L.] the smallest of the three pelvic bones, forming the cranial portion of the pelvic floor. See also Table 9. Called also pubic bone.

• public health the field of human medicine that is concerned with safeguarding and improving the physical, mental, and social well-being of the community as a whole. The role for veterinarians in this service rests especially in the areas of control of zoonotic agents at the level of the farm, food safety, and food-borne diseases; see also one health.

  • veterinary p. health the part played by veterinarians in human public health, relating chiefly to the recognition and control of zoonotic disease and in food safety.

• public programs see public program.

• PubMed® a free electronic search engine for accessing the MEDLINE® database of publications in the National Library of Medicine.

• pubocaudal muscles [pu″bo-kaw′d l] the more caudal of the two parts of the levator ani muscles; origin at the dorsal surface of the pubis; insertion at the ventral surface of the caudal vertebrae.

• pubofemoral [pu″bo-fem′ -r l] pertaining to the pubis and femur.

• pubovesical [pu″bo-ves′ľ-k l] pertaining to the pubis and bladder.

• Puccinia graminis a toxic fungus in the phylum Basidiomycota that contains an unidentified toxin that causes salivation and stomatitis and, in severe cases, death of horses.

• Pudelpointer a combination of pointer and poodle, this German hunting breed has a short, rough coat of dark liver to black. The tail is docked.

• pudendal [pu-den′d l] pertaining to the pudendum.

  • p. fissure see rima pudendi.

• pudendum [pu-den′d m] pl. pudenda [L.] the external genitalia, especially of the human female (pudendum femininum).

• pudic [pu′dik] pudendal.

• Pueraria lobata a coarse, perennial leguminous vine. Has woody stems but very palatable and nutritious foliage equal in value to alfalfa. Called also kudzu.

  P-84.

  

  Pug

  P-85.

  

  Puli

• puerperal [pu-ur′p r- l] pertaining to a puerpera or to the puerperium.

  • p. fever see mastitis–metritis–agalactia.
  • p. laminitis see laminitis.
  • p. metritis infection of the uterus in a puerperal female.
  • p. tetanus see tetanus.
  • p. tetany see puerperal tetany.

• puerperalism a morbid condition incident to parturition.

• puerperium [pu″ r-pēr′e- m] the postpartum period or period between parturition and uterine involution.

• PUFA polyunsaturated fatty acids.

• puff disease [puf] see anhidrosis.

• puffer [puf′ r] highly venomous fish in the family Tetraodontidae. Called also toadfish, balloonfish.

  • p. fish poison see tetrodotoxin.

• puffin fish eating, diving sea birds in the genus Fratercula, found in northern subarctic regions, typically in colonies on cliff faces. They are black and white with large, brightly colored beaks and feet. There are three species, the Atland puffin (F. arctica), horned puffin (F. corniculata), and tufted, or crested, puffin (F. cirrhata). Hunted in some countries.

• Puffin dog see Norwegian Lundehund.

• Pug a small (14–18 lb), cobby dog with a large rounded head, prominent eyes, very short nose, and large, deep wrinkles on the forehead and face. The small ears fold over, the tail is curled over the back, and the coat is fine and very short in black, silver, apricot, or fawn with a black mask. Called also Mopshond. The breed is predisposed to pigmentary keratitis and proptosis.

• pugging see poach.

• puggle 1. a young monotreme before weaning. 2. a crossbreed dog from Pug and a Beagle parents; one of the designer dogs.

• pukatea see Laurelia novae-zealandiae.

• pulegone a toxic ketone found in pennyroyal oil. It causes hepatotoxicity in dogs and cats.

• Pulex [pu′leks] a genus of fleas, several species of which transmit the microorganism causing bubonic plague in humans.

  • P. irritans a widely distributed species, known as the human flea, which infests domestic animals as well as humans, and may act as an intermediate host of certain helminths.
  • P. porcinus the peccary flea.

• Puli a medium-sized dog distinguished by its long, wiry haircoat, usually black, gray, or white, that forms long, tightly coiled cords, similar to dreadlocks, in adults, which obscure the body features. In the US, dogs may be shown either corded or brushed. The breed was developed for guarding and driving sheep. Called also Hungarian Puli.

• pulicicide an agent destructive to fleas.

• pull [p $\stackrel{⌣}{o}$ $\stackrel{⌣}{o}$ l] to remove a sick animal from a pen in a feedlot for treatment. See also daily pull and dead records.

• pull rate a daily percentage of the cattle in a feedlot that are pulled out of the feeding pens and relegated to the hospital yards or sent for emergency slaughter.

• pull-out suture pattern removable, nonabsorbable, interrupted sutures for apposition of deep tissues. The suture starts on one side of a wound, crosses it at right angles at the deep tissues. Having taken a bite of these tissues, it returns to the entry side and emerges at the skin close to the entry. Individual sutures are inserted on both sides in an alternating pattern.

• pull-through [pool′throo] the term given to a surgical technique for abdominoperineal resection of the rectum. After removal of a segment, the rectum is sutured to the perineal skin, forming a new mucocutaneous junction. Used in the treatment of rectal neoplasms and anal furunculosis.

• pullet young, female fowl from end of brooding period at about 4 weeks of age, up to point of lay at about 5 months. In some circles the first laying season is referred to as the pullet year.

  • p. disease see visceral gout.

• pullorum disease a disease of birds caused by infection with Salmonella pullorum and characterized by moribund and dead birds at hatching time, sometimes by dyspnea and diarrhea in older birds and a reduction in egg yield, and reduction in fertility of the eggs in adults. The disease, which has been largely eradicated, is notifiable to the OIE (see Table 20).

• pullulation [pul″u-la′sh n] development by sprouting, or budding.

• pulmo [pool′mo] pl. pulmones [L.] lung.

• pulm(o)- word element. [L.] lung. See also words beginning pulmon(o)-.

• pulmoaortic [pool″mo-a-or′tik] pertaining to the lungs and aorta.

• pulmonary [pool′mo-nar″e] pertaining to the lungs, or to the pulmonary artery. See also lung.

  • p. abscess an abscess within the lung; due either to hematogenous or aerogenous bacterial infection. May cause a syndrome of chronic toxemia, cough, loss of body weight. Careful auscultation may elicit squeaky rales around the lesions. See also vena caval thrombosis, aspiration pneumonia.
  • p. acinus basic structural unit of the lung parenchyma; the gas exchange unit, supplied by a single terminal bronchiole and includes branches of the terminal bronchiole, alveolar ducts, alveolar sacs, alveoli, and associated blood vessels. A pulmonary lobule consists of many acini.
  • p. agenesis incompatible with life; found only in fetal or neonatal necropsy specimens.
  • p. alveolar microlithiasis see microlithiasis alveolaris pulmonum.
  • p. alveolar parenchyma include epithelial cells (pneumonocytes or pneumocytes), alveolar capillary endothelial cells, and interstitial cells (fibroblasts) and alveolar macrophages.
  • p. alveolar proteinosis a disease of unknown etiology marked by chronic filling of the alveoli with a proteinaceous, lipid-rich, granular material consisting of surfactant and the debris of necrotic cells.
  • p. arteriopathy pulmonary arterial and arteriolar medial smooth muscle hypertrophy and hyperplasia and intimal proliferation leads to pulmonary hypertension; commonly secondary to parasitic infection in cats, particularly Aelurostrongylus abstrusus and Dirofilaria immitis.
  • p. artery wedge pressure see wedge pressure.
  • p. atelectasis see atelectasis.
  • p. bed the network of capillaries in lung tissue.
  • p. calcinosis see microlithiasis alveolaris pulmonum.
  • p. calculus see bronchial calculus.
  • p. carcinomatosis see ovine pulmonary adenomatosis (below).
  • chronic obstructive p. disease (COPD) a disease of mature horses characterized by bronchoconstriction, airway wall thickening, and mucus overproduction, due to exposure to dust, fungal spores, and an endotoxinladen barn environment. Occurs in horses with a significant genetic linkage of seven chromosomal regions. It is a well-identified and common syndrome of chronic respiratory disease. Clinical signs include chronic cough, loud abnormal breath sounds, a double expiratory effort, and abundant mucopurulent material in the trachea on endoscopic examination. Called also asthma, heaves broken wind.
  • p. circulation the circulation of blood to and from the lungs. Deoxygenated blood from the right ventricle flows through the right and left pulmonary arteries to the right and left lung. After entering the lungs, the branches subdivide, finally emerging as capillaries that surround the alveoli and release the carbon dioxide in exchange for oxygen. The capillaries unite gradually and assume the characteristics of veins. These veins join to form the pulmonary veins, which return the oxygenated blood to the left atrium. See also circulatory system.
  • p. compliance a measure of the ability of the lung to distend in response to pressure without disruption. Expressed as the unit volume of change in the lung per unit of pressure. Compliance or distensibility of the lung is increased in conditions such as emphysema in which the lung distends more readily, and is decreased in fibrotic conditions in which the lung distends with difficulty. See also compliance.
  • p. congestion caused by engorgement of the pulmonary vascular bed, and it may precede pulmonary edema when the intravascular fluid escapes into the parenchyma and the alveoli. There is a loss of air space and the development of respiratory embarrassment.
  • p. cysts may be congenital or acquired, caused by trauma, parasites (Paragonimus spp.), or associated with bronchiectasis. Rarely, metastatic tumors cavitate forming cysts.
  • p. defense mechanisms include aerodynamic filtration in nasal cavities, sneezing, local nasal antibody, laryngeal and cough reflexes, mucociliary transport mechanisms, alveolar macrophages, and systemic and local antibody systems.

    P-86.

    

    Intrapulmonary hemorrhage attributable to erosion of the pulmonary artery by a lung abscess in a cow with caudal vena caval thrombosis. Immediately adjacent to this, purulent material is seen exiting a lung abscess that has been cut open

  • p. embolus obstruction of the pulmonary artery or one of its branches by an embolus. The embolus usually is a blood clot swept into circulation from a large peripheral vein. Signs vary greatly, depending on the extent to which the lung is involved. Simple, uncomplicated embolism produces such cardiopulmonary signs as dyspnea, tachypnea, persistent cough, pleuritic pain, and hemoptysis. On rare occasions, the cardiopulmonary signs may be acute, occurring suddenly and quickly producing cyanosis and shock. A septic embolus can lead to local pulmonary abscess or an extension to pneumonia as in caudal vena caval syndrome. See also vena caval thrombosis, pulmonary abscess (above).
  • p. eosinophilic granulomatosis a lesion common in canine heartworm disease; eosinophils and neutrophils surround trapped microfilariae in the lungs causing nodules as large as 3 in. diameter. May be preceded by lesions of allergic (eosinophilic) pneumonitis.
  • exercise-induced p. hemorrhage traces of blood can be found in about 60% of horses after racing. Less than 1% of these bleed from the nostrils, but the syndrome is a cause for poor performance as well as potential premature athletic retirement. A public concern is its visual occurrence, and the routine use of medications, such as furosemide, to prevent it. See also epistaxis.
  • idiopathic p. fibrosis recognized in West Highland white terriers. Affected dogs develop breathing difficulties, cough, cyanosis, and exercise intolerance due to fibrosis throughout the lung interstitium and secondary pulmonary hypertension. The cause is unknown but a genetic predisposition is suspected.
  • p. function tests tests used to evaluate lung mechanics, gas exchange, pulmonary blood flow, and blood acid–base balance. Pulmonary function testing is used to detect emphysema and chronic obstructive bronchitis at an early stage.
  • p. hemorrhage as distinct from hemothorax, is recognized because of a syndrome of dyspnea, increased lung density radiographically, and hemorrhagic anemia. If a large vessel ruptures into an abscess cavity there is usually a massive hemoptysis and instant death. Frothy blood-stained nasal discharge is an indication of pulmonary edema rather than of pulmonary hemorrhage. See also exercise-induced pulmonary hemorrhage (above).
  • p. horse sickness the predominantly pulmonary form of African horse sickness.
  • p. hypertrophic osteoarthropathy see hypertrophic osteopathy.
  • p. hypoplasia a congenital defect resulting in decreased lung development.
  • p. hypoplasia with anasarca lethal autosomal recessive disorder to Shorthorn, Chianina, Dexter, and Maine-Anjou cattle manifest with mid-pregnancy fetal loss or dystocia, profound anasarca, and death of the full-term calf, and post dystocial sickness or death of the dam.
  • p. infarction see pulmonary infarction, pulmonary embolus (above).
  • p. infiltrates with eosinophils (PIE) see eosinophilic bronchopneumopathy.
  • p. malformation includes accessory lungs, pulmonary hypoplasia, pulmonary agenesis, congenital pulmonary cysts, endodermal heteroplasia, respiratory distress syndrome, neonatal maladjustment syndrome, immotile cilia syndrome.
  • p. mycoses includes aspergillosis, mortierellosis, blastomycosis, cryptococcosis, coccidioidomycosis.
  • p. neoplasm many types are recorded in all species, but the prevalence is very low in food animals. A common site for metastases in companion animals. Characterized clinically by decreased exercise tolerance, progressive dyspnea, chronic cough, and emaciation. Most diagnoses result from radiographic examination of the thorax for secondary growths.
  • overriding p. artery see overriding pulmonary artery.
  • ovine p. adenomatosis chronic progressive pneumonia of mature sheep caused by a retrovirus transmitted by the respiratory route. Sporadic occurrence with geographic clustering. Progressive dyspnea, emaciation, and a profuse nasal discharge are the cardinal signs, but coughing is not a feature. The disease is always fatal. It is of great importance if it occurs in flocks that are housed for long periods. Characteristically, the extensive lung involvement includes large areas of neoplastic tissue. Called also jaagsiekte, pulmonary adenomatosis.
  • p. patterns see alveolar, interstitial, bronchial pattern.
  • re-expansion p. edema edema, emphysematous bullae, and serosanguinous fluid in the airways with generalized pulmonary capillary endothelial damage; associated with chronic pulmonary collapse and removal of pleural effusions or pneumothorax with rapid re-expansion.
  • p. rupture traumatic, especially when there is rib fracture, or spontaneous due to coughing and a weak parenchyma. The most common cause of pneumothorax.
  • summer pasture-associated obstructive p. disease a disease of mature horses characterized by recurrent airway obstruction and so named because it affects grazing horses during the summer months. Pathophysiological characteristics of the disease include airway inflammation, increased airway mucus production and bronchoconstriction.
  • p. thromboembolic disease thromboembolism causing blockage of large sections of the pulmonary vascular bed will result in at least temporary severe dyspnea. It may also lead to right heart congestive failure, i.e., cor pulmonale.
  • p. thrombosis see thromboembolism.
  • p. valve any one of the three semilunar cusps or valvulae that individually form the pocket-like structure that guard the orifice between the right ventricle and the pulmonary artery or, similarly, between the left ventricle and aorta.
  • p. valve stenosis causes right ventricular hypertrophy and a poststenotic dilatation of the pulmonary artery. There is a systolic murmur and thrill on the left side of the chest. A common congenital defect in dogs.
  • p. vascular resistance resistance to blood flow in the pulmonary circulation. See also systemic vascular resistance.
  • p. vein the large vein (right and left branches) that carries oxygenated blood from the lungs to the left atrium of the heart.
  • p. wedge pressure see wedge pressure.

• pulmonic [p l-mon′ik] pulmonary.

  • p. stenosis a common congenital anomaly in dogs, but rare in other species. Inherited in Beagles, probably in Chihuahuas, English bulldog, and terrier breeds. It may occur in supravalvular, valvular (most common), or subvalvular (infundibular) locations. Characterized by a loud systolic ejection murmur at the left heart base; accompanied by right ventricular hypertophy. Severity of the condition can be assessed by Doppler echoderived pressure gradient across the pulmonic valve. Correction is accomplished by several surgical techniques and by balloon valvuloplasty.

• pulmonitis [pool″mo-ni′tis] inflammation of the lung; pneumonitis; pneumonia.

  • eosinophilic p. an allergic reaction to dying microfilaria in pulmonary capillaries of dogs with heartworm disease.

• pulmon(o)- word element. [L.] lung. See also words beginning pulm(o)-.

• pulmotor historically, the first artificial respiration device that could automatically deliver gas and/or air at specific volumes.

• pulp [pulp] any soft, juicy animal or vegetable tissues, e.g., citrus pulp.

  • p. canal root canal.

    P-87.

    

    Pulmonic stenosis in a dog

    P-88.

    

    Pulpitis of the left mandibular canine tooth

  • p. cap pulp of the feather produced inside the calamus by the follicular tissue. The pulp protrudes through the aperture in the wall of the shaft and forms the external pulp caps. Internal pulp caps are formed within the calamus.
  • p. cavity the pulp chamber and the root canal in a tooth. In the young, it is wide, but with age it gradually becomes narrower with deposition of secondary dentin.
  • p. chamber space within the crown of the tooth that contains most of the pulp.
  • dental p. the sensitive content of the cavity of the tooth carrying its nerve and blood supply.
  • p. polyp superficial hyperplasia of dental pulp, usually after exposure due to injury such as fracture of a tooth.
  • red p., splenic p. the dark reddish brown substance filling the interspaces of the splenic sinuses.
  • tooth p. dental pulp.
  • white p. sheaths of lymphatic tissue surrounding the arteries of the spleen.

• pulpa [pul′p ] pl. pulpae [L.] pulp.

• pulpal [pul′p l] pertaining to pulp, usually dental.

  • p. stones small calcified deposits in the pulp cavity.

• pulpectomy [p l-pek′t -me] complete removal of dental pulp.

  • partial p. partial excision of the pulp in a vital tooth.

• pulpefaction conversion into pulp.

• pulpitis [p l-pi′tis] pl. pulpitides [L.] inflammation of dental pulp.

• pulpy [pul′pe] soft; having the consistency of pulp.

  • p. kidney diseaseClostridium perfringens (type D) enterotoxemia.

• pulsatile [pul′s -tīl] characterized by a rhythmic pulsation.

• Pulsatilla vulgaris Anemonepulsatilla.

• pulsation chamber [p l-sa′sh n] space between the teat cup shell and the liner of a milking machine teat cup.

• pulsator [pul′sa-t r] mechanism in a milking machine that governs the cyclic pressure changes necessary to the function of the machine.

• pulse [puls] 1. a rhythmic wave. 2. any leguminous seed used in animal feed or human food. Contain about 20% protein.

  • abdominal p. that over the abdominal aorta.
  • p. abnormality includes irregularity of timing, character, and amplitude, examples are large or small amplitude, waterhammer pulse, Corrigan’s pulse, dropped pulse, pulse deficit, alternating pulse, and many others, a strong indication of cardiac disease.
  • alternating p. pulsus alternans; one with regular alteration of weak and strong beats without changes in cycle length.
  • p. amplitude indicative of arterial blood pressure; estimated on the difference of pressure exerted by the fingers to occlude and then reopen the arterial pulse.
  • anacrotic p. one in which the ascending limb of the tracing shows a transient drop in amplitude, or a notch.
  • anadicrotic p. one in which the ascending limb of the tracing shows two small additional waves or notches.
  • anatricrotic p. one in which the ascending limb of the tracing shows three small additional waves or notches.
  • arterial p. the wave of pressure generated by the ejection of blood from the left ventricle into the aorta. Although the size (amplitude) of the pulse depends on the volume ejected it is not the blood passing the finger that is palpated, it is only the pressure wave. The pulse is a good indicator of the heart’s activity with respect to amplitude, rate, and regularity. It may also provide information on the state of the vessel walls and the efficiency of the aortic semilunar valves. It may be palpated in the median, facial, femoral, or coccygeal arteries, the preferred site varying with the species and the occasion.
  • atrial venous p. atriovenous pulse, a cervical pulse having an accentuated ‘a’ wave during atrial systole, owing to increased force of contraction of the right atrium; a characteristic of atrial hypertrophy and tricuspid stenosis.
  • B-B shot p. see water-hammer pulse (below).
  • bigeminal p. one in which two beats occur in rapid succession, the groups of two being separated by a longer interval, usually caused by ventricular bigeminy.
  • catadicrotic p. see catadicrotism.
  • catatricrotic p. see catatricrotism.
  • p.-chase experiment to study the movement of molecules, cells are incubated with a labeled precursor (pulse) and then replaced with unlabeled precursor (chase). The label can be followed as it is incorporated into newly synthesized compounds and through different cellular compartments. Radioactivity is commonly used as the label.
  • Corrigan’s p. see Corrigan’s pulse.
  • p. deficit the difference between the apical pulse (apex beat) and the radial pulse. Obtained by counting apical beats as heard through a stethoscope over the heart and counting the arterial pulse at the same time. A characteristic of several arrhythmias.
  • dicrotic p. a pulse characterized by two peaks, the second peak occurring in diastole and being an exaggeration of the dicrotic wave.
  • p. dosing the administration of drugs, usually antibiotics or corticosteroids, in a single, large dose that might be repeated after an interval of days. Thought to have the advantage of high tissue concentrations and fewer of the undesirable side–effects associated with more frequent dosing.
  • dropped p. a specific pulse deficit characterized by the absence of a palpable pulse when one is expected. Occurs with a variety of cardiac arrhythmias.
  • femoral p. that which is located at the site where the femoral artery passes through the groin in the femoral triangle; the usual site for palpating the pulse in dogs and cats.
  • fetal p. detector an ultrasound detector based on the Doppler principle used to detect the presence of a living fetus in utero.
  • funic p. the arterial tide in the umbilical cord.
  • p. generator the power source for a cardiac pacemaker system, usually powered by a lithium battery. It supplies electrical impulses to the implanted electrodes. See also pacemaker.
  • hard p. one characterized by high tension.
  • irregular p. caused by cardiac arrhythmia or inadequate ventricular contractions failing to open aortic semilunar valves.
  • jerky p. see water-hammer pulse (below).
  • jugular p. 1. in the normal animal, consists of three positive waves in each cardiac cycle, commonly called ‘a’, ‘c’, and ‘v’, with ‘a’ produced by right atrial contraction, ‘c’ by the bulging of the tricuspid valve into the right atrium during early ventricular contraction, and ‘v’ by the increase in blood volume in the venae cavae and the right atrium during ventricular systole when the triscuspid valve is closed. Commonly visible in horses and cattle. 2. a large pulse that goes high up the neck when the head is in the normal position and that is synchronous with the heart cycle and is systolic in time, indicates insufficiency of the right atrioventricular valve.
  • p. monitor a pulse detector which uses the Doppler principle.
  • paradoxical p. one that markedly decreases in amplitude during inspiration. Associated with cardiac tamponade.
  • peripheral p. that palpable in the extremities, e.g., legs, neck, and head; the usual sites for measuring the pulse rate.
  • pistol-shot p. 1. one in which a sharp cracking sound associated with the pulse can be heard through a stethoscope placed over the artery. Occurs where the arteries are subject to sudden distention and collapse as with a water-hammer pulse. 2. sound that can be auscultated over the jugular vein in association with tricuspid insufficiency in cattle that have high mountain altitude sickness.
  • p. pressure the difference between the systolic and diastolic pressures.
  • radial p. that felt over the radial artery.
  • p. rate the number of pulsations per minute palpable in an artery, usually of a limb. The normal rates per minute for the common domestic animal species are: horses, 30–40; young horses up to 1 year of age, 70–80; cattle, 60–80; young calves, 100–120; sheep and goats, 70–120; pigs (heart rate), 60–70; llama, alpaca 60–90; dogs, 100–130; cats, 110–240; adult fowls 250–300.
  • p. rhythm regularity of the pulse in time and amplitude.
  • thready p. one that is very fine and barely perceptible.
  • p. tracing see sphygmogram.
  • trigeminal p. one with a pause after every third beat.
  • undulating p. one giving the sensation of successive waves.
  • vagus p. a slow pulse.
  • venous p. the pulsation over a vein.
  • water-hammer p. one in which the artery is suddenly and markedly distended and relaxed. Characteristic of patent ductus arteriosus. Called also Corrigan’s, jerky, and B-B shot pulse.
  • wiry p. a small, tense pulse.
  • irregular p. caused by cardiac arrhythmia or inadequate ventricular contractions failing to open aortic semilunar valves.

• PulseNet a national surveillance system in the US coordinated by the Centers for Disease Control and Prevention that allows state and local public health epidemiologists to compare pulsed-field gel electrophoresis profiles of foodborne disease-causing bacteria such as Salmonella, Shigella, Listeria, Campylobacter, and Escherichia coli O157:H7 from all US regions.

• pulsed electromagnetic field magnet see magnetic field therapy.

• pulsion [pul′sh n] a pushing outward.

• pulsus [pul′s s] [L.] pulse.

  • p. alternans see alternating pulse.
  • p. bigeminus bigeminal pulse.
  • p. bisferiens a pulse characterized by two systolic peaks separated by a midsystolic dip. Most commonly occurring in aortic regurgitation.
  • p. celer a rapidly rising and rapidly falling pulse. Also called waterhammer pulse, as can be felt in the femoral arteries of small animals with patent ductus arteriosus.
  • p. differens inequality of the pulse observable at corresponding sites on either side of the body.
  • p. paradoxus see paradoxical pulse.
  • p. parvus et tardus a hypokinetic pulse
  • p. tardus an abnormally slow pulse.

• pultaceous [p l-ta′sh s] pulpy’ like a poultice.

• pulverization [pul″v r-ľ-za′sh n] in dentistry, high-speed burs may be used to remove root fragments that cannot be extracted or are ankylosed.

• pulverulent [p l-ver′u-l nt] powdery; dusty.

• pulvinar [p l-vi′n r] the posterior medial part of the posterior end of the thalamus.

• pulvinus [p l-vi′n s] cushion, pad.

  • p. dentalis the dental pad that replaces the upper incisors in the mouth of ruminants.
  • p. digitalis the digital cushion, a pad of fat, white fibrous, and elastic tissue located between the distal phalanx and the sole and frog of the hoof of the horse.

• puma see cougar.

• Pumi a medium-sized Hungarian herding dog with a black, white, gray, or fawn coat that forms corkscrews or curls all over the body. Similar to the Puli. Called also Hungarian herding terrier.

• pumice [pum′is] a substance consisting of silicates of aluminum, potassium, and sodium; used in dentistry as an abrasive during polishing of teeth.

  • p.-stone lung microlithiasis alveolaris pulmonum.

• pumiced hoof a rough, porous appearance of the hoof in a horse with chronic coronitis.

• pump [pump] 1. an apparatus for drawing or forcing liquid or gas. 2. to draw or force liquids or gases. 3. a mechanism or structure that mediates active transport of ions or molecules across a biological membrane.

  • blood p. a machine used to propel blood through the tubing of extracorporeal circulation devices.
  • calcium p. the mechanism of active transport of calcium (Ca²⁺) across a membrane, as of the sarcoplasmic reticulum of muscle cells, against a concentration gradient; the mechanism is driven by hydrolysis of ATP.
  • chloride p. an active secretory process at a barrier membrane that facilitates the transfer of chloride ions across the membrane.
  • Gomco p. standard suction kit including electric motor, pump, and collecting jar.
  • infusion p. an electronic device used to control the administration of intravenous fluids in very small amounts and at a carefully regulated rate over long periods.
  • insulin p. a computerized device containing a reservoir filled with a predetermined amount of short-acting insulin worn outside the body, a plastic cannula and a needle inserted under the skin, and a pump that periodically delivers the desired amount of insulin. Sometimes used in humans, but of limited application in animals.
  • ion p. see Ca²⁺-ATPase, Na,⁺, K⁺-ATPase.
  • p. oxygenator heart–lung machine. See extracorporeal circulatory support unit.
  • proton p. inhibitors see proton pump inhibitor.
  • stomach p. an apparatus used to remove material from the stomach. It consists of a rubber stomach tube to which a bulb syringe is attached. The tube is inserted into the mouth or nose and passed down the esophagus into the stomach. Suction from the syringe brings the contents of the stomach up through the tube. For cattle and horses, a reversible metal pump adapted from a yachting bilge pump is most suitable. In small animals, gravity is the usual method of moving fluid into and out of the stomach during lavage.

• pumpkin [pump′kin] large edible fruit, used as cattle feed and for human consumption, Cucurbita maxima.

• punch [punch] a metal, rod-like instrument with one pointed or cavitied end and one propulsion end to be pushed hard with the palm of the hand or driven with a hammer in order to drive a hole or to excise a small round piece of tissue.

  • p. biopsy a circular piece of skin excised by a hand driven biopsy punch.
  • dental p. has a slight cavity at the end so that the tooth to be driven will seat into the end and not slip off.

• puncta [punk′t ] plural form of punctum.

  • p. maxima points on the chest wall where heart sounds are heard best.

• punctate [punk′tāt] spotted; marked with points or punctures.

• punctiform [punk′tľ-form] like a point.

• punctum [pungk′t m] pl. puncta [L.] a point or small spot.

  • imperforate lacrimal p. congenital absence of the lacrimal punctum, usually the inferior punctum. Instead the proximal end of the lacrimal canaliculus is covered by a conjunctival membrane. Occurs most often in dogs, especially Cocker spaniels and a number of toy or miniature breeds where it is manifest as epiphora.
  • lacrimal p. see lacrimal punctum.
  • nasolacrimal p. see lacrimal punctum.

    P-89.

    

    (A) Slit form of constricted feline pupil. (B) Round form of dilated feline pupil

  • obstructed p. acquired blockage of a congenitally patent lacrimal punctum; may result from foreign bodies, accumulation of debris or inflammation, or cicatrization of the canaliculus or associated conjunctival or eyelid tissues.

• puncture [pungk′ch r] 1. the act of piercing or penetrating with a pointed object or instrument; a wound so made. Wounds of special interest because of their potential seriousness are to the cornea, the sole of the horse’s foot and the synovial cavity. 2. surgical puncture of an anatomical tissue to obtain material for clinicopathological examination. Includes cisternal puncture, lumbar puncture, spinal puncture, sternal puncture.

• puncture vine see Tribulus terrestris.

• punishment the use of an undesirable stimulus to modify or prevent an undesirable behavior.

• punkies see biting midge.

• puntilla a short, double-edged, stabbing knife that is plunged into the occipitoatlantal space to sever the medulla oblongata in the evernazione method of slaughter.

• Puntius [pun′te- s] a genus of fish in the family Cyprinidae, often called spotted barbs. Many are brightly colored and patterned; they are popular as aquarium fish.

• PUO pyrexia of unknown origin. See FUO.

• pupa [pu′p ] pl. pupae [L.] the second stage in the development of an insect, between the larva and the imago. Usually an inactive stage such as a coccoon.

• puparium the hard pupal case of the insect pupa.

• pupate to proceed to the stage of pupa in an insect life cycle.

• pu/pd polyuria/polydipsia.

• pull theory a theory of wound healing and contraction stating that material within the healing wound contracts and pulls the margins of the wound together.

• pupil [pu′pil] the aperture in the center of the iris that regulates the amount of light that reaches the retina.

  • Adie’s (tonic) p. see tonic pupil (below).
  • dilated p. syndrome see dysautonomia.
  • fixed p. a pupil that does not change size on exposure to changes in illumination or (in primates) on convergence or during accommodation.
  • multiple p’s polycoria.
  • occluded p. a congenital or acquired membrane (usually fibrovascular) that obstructs the pupil.
  • secluded p. a complete posterior synechia that separates the anterior and posterior chambers of the eye.
  • spastic p. syndrome anisocoria in cats infected with feline leukemia virus. The degree of anisocoria and even which pupil is smaller can vary greatly over short periods of time. The virus has been observed in the short ciliary nerves and ciliary ganglia of some affected cats.
  • tonic p. see pupilloplegia.

• pupilla [pu-pil′ ] [L.] pupil.

• pupillary [pu′pľ-lar-e] pertaining to or emanating from the pupil.

  • p. aperture the pupil.
  • p. block an obstruction to the flow of aqueous between the pupillary border of the iris and the anterior lens capsule. Can cause glaucoma.
  • consensual p. light reflex the reflex constriction of the pupil of a non illuminated eye when light is directed into the fellow eye.
  • p. constriction see miosis.

    P-90.

    

    Iris-iris persistent pupillary membrane in a dog

  • p. dilation see mydriasis.
  • p. light reflex constriction of a pupil in response to an increase in light intensity. Used to assess in a coarse manner function of the retina, optic nerve, radiation, and tract, as well as the oculomotor nerve and the musculature of the iris. Does not verify visual cortical function.
  • p. membranectomy a surgical technique for resection of a fibro-vascular adhesion between the iris and lens capsule formed as a sequela to cataract surgery.
  • persistent p. membrane (PPM) a congenital and sometimes inherited embryological defect in which remnants of the anterior tunica vasculosa lentis persist beyond birth. Considered pathologic when they persist beyond a few months of age. These are pigmented and sometimes vascular elements that arise from the iris collarette and extend to another region of the collarette (iris-to-iris PPMs) to the cornea (iris-to-cornea PPMs) or to the lens (iris-to-lens PPMs). The latter two forms typically produce an adherent leukoma or cataract, respectively, that can affect vision, while iris-to-iris PPMs are typically of no clinical relevance. Seen most commonly in dogs, particularly Basenjis.
  • p. zone one of the three regions of the iris. the pupillary zone comprises the innermost region of the iris near the pupillary border. See also ciliary zone and iris collarette.

• pupillatonia [pu″pil- -to′ne-] dilated pupil due to parasympathetic denervation.

• pupillodilator 1. a mechanism responsible for dilation of the pupil. 2. a substance having the effect of dilating the pupil.

• pupillometer [pu″pľ-lom′ -t r] an instrument for measuring the diameter of the pupil.

• pupillometry [pu″pľ-lom′ -tre] measurement of the diameter of the pupil of the eye.

• pupillomotor [pu″pľ-lo-mo′t r] pertaining to the movement of the pupil. Includes pupilloconstrictor, pupillodilator.

  • p. pathways the nerves and mediators involved in regulating the size of the pupil.

• pupilloplegia [pu″pľ-lo-ple′j ] a dilated or “tonic” pupil that responds slowly or incompletely to a bright source.

• pupilloscopy [pu″pľ-los′k -pe] skiametry; retinoscopy.

• pupillostatometer [pu-pil″o-st -tom′-t r] an instrument for measuring the distance between the pupils.

• puppy the young of the canine species; usually used up to the age of 12 months.

  • fading p. syndrome see fading kitten/puppy syndrome.
  • p. pyoderma see impetigo.
  • p. strangles see juvenile pyoderma.

• puppy mill the term applied to intensive canine breeding establishments where breeding stock are maintained expressly to produce puppies for profit in a commercial marketplace, most often pet stores. They are frequently criticized by animal welfare authorities for their inhumane conditions, poor husbandry and disease control, and lack of socialization for the puppies. The federal Animal Welfare Act (1966), and regulations in many jurisdictions are aimed at controlling these practices. Called also puppy farms.

• purebred progeny derived from at least several generations of animals of the same breed, achieved through the process of selective breeding.

  • p. herds herds (or flocks) composed of purebred animals. Not necessarily registered animals. Distinct from crossbred herds.
  • p. pedigree pedigree of a purebred animal.

• purgation [p r-ga′sh n] the effect of a purge; catharsis; purging effected by a cathartic medicine.

• purgative [pur′g -tiv] 1. an agent that causes purging or bowel evacuation; a cathartic agent, particularly one that stimulates peristaltic activity. 2. a cathartic, particularly one stimulating peristaltic action. See also laxative.

• purge [purj] 1. a purgative medicine or dose. 2. to cause free evacuation of feces. 3. a cathartic.

  • p. nutJatropha curcas.

• purging pertaining to purge.

  • p. ball a bolus given periodically to horses by owners and trainers in the belief that a good clean-out is good for a horse, especially if it is racing poorly. Usually contains aloes; 7–14 g (2–4 drachms) is the usual dose. Anthraquinone purgatives are more reliable in their action but the procedure is basically empirical and is not recommended by veterinarians. Called also physic ball.
  • p. nut Jatrophacurcas.

• purified protein derivative see purified protein derivative of tuberculin.

• purine [pu′rēn] a heterocyclic compound that is the nucleus of the purine bases (or purines) such as adenine and guanine, which occur in DNA and RNA, and xanthine and hypoxanthine. All living cells contain purines as purine nucleotides. They can be synthesized using amino acids, or by salvage of dietary or endogenous nucleotides derived from cell wastage.

  • low p. diet one with a low content of organ meats, seafood, beans, lentils, peas, and spinach; used in the dietary management of xanthine or urate uroliths in dogs.
  • p. nucleoside phosphorylase a transferase enzyme that acts in the degradation of nucleotides and nucleic acids.

• Purkinje [p r-kin′je] named after J.E. Purkinje, Bohemian anatomist (1787–1869).

  • P. cell neuronal cell bodies in the middle layer of the cerebellar cortex; characterized by a large, globose body and massive, branching dendrites but a single, slender axon.
  • P. fiber modified cardiac muscle fibers in the subendothelial tissue, concerned with conducting impulses through the heart.
  • P’s image, P.–Sanson images in a normal eye, reflections of light off the surface of the cornea, anterior lens capsule, and posterior lens capsule. When viewed from different angles, can be used to judge depth of lesions within the eye.
  • P. network a reticulum of modified muscle fibers in the subendocardial tissue of the cardiac ventricles.
  • P. neuron see Purkinje cell (above).

• puromycin [pūr″o-mi′sin] an antibiotic that inhibits protein synthesis. Used in the treatment of protozoal infections (trypanosomiasis) and as an anti-neoplastic agent

• purple cudweed [pur′p l] Gnaphalium purpureum.

• purple top Verbenabonariensis,Brassicarapa.

• purpura [pur′pu-r ] a hemorrhagic disease characterized by extravasation of blood into the tissues, under the skin and through the mucous membranes, and producing spontaneous ecchymoses and petechiae on the skin. Similar lesions are produced in many specific diseases, e.g., epizootic hemorrhagic disease, bracken poisoning in cattle, and leptospirosis in calves. In immune-mediated purpura, there is a defect in the integrity of the vessel wall due to immunological mechanisms, which may also cause a thrombocytopenia.

  • anaphylactoid p. immune-mediated purpura; see also purpura.
  • fibrinolytic p. purpura associated with increased fibrinolytic activity of the blood.
  • p. hemorrhagica a well-defined disease of horses, occurring sporadically, usually associated with a respiratory tract infection and the result of the deposition of immune complexes in the walls of capillaries resulting in vasculitis and extravasation of blood and plasma. Clinical signs include cold, subcutaneous, edematous swellings, usually about the head and not always symmetrical, mucosal petechiation, and high heart rate; affected horses commonly die within a few days. Nonthrombocytopenic.

    P-91a.

    

    Purpura hemorrhagica, side view

    P-91b.

    

    Purpura hemorrhagica, front view

  • neonatal p. a severe bleeding disease in piglets a few days old that have drunk colostrum containing antiplatelet antibody from their alloimmune dam. Occurs also in foals for unknown causes and in calves associated with type II bovine viral diarrhea virus infection. See also alloimmune thrombocytopenia, alloimmune hemolytic anemia of the newborn.
  • nonthrombocytopenic p. purpura without any decrease in the platelet count of the blood. In such cases the cause of purpura is either abnormal capillary fragility or a clotting factor deficiency.
  • thrombocytopenic p. purpura associated with a decrease in the number of platelets in the blood. See also immune-mediated thrombocytopenia.
  • vascular p. that caused by loss of vascular integrity or function, as seen in vitamin C deficiency (scurvy), vasculitis, diabetes mellitus, and hyperadrenocorticism.

• purring [pur′ing] a physiologically very complicated, semi-automatic, cyclic, controlled respiration involving alternating activity of the diaphragm and intrinsic laryngeal muscles in cats. The frequency of the alternation is about 25 times per second. Each cycle includes three phases of glottal closing, glottal opening with sound produced, further glottal opening with rapid airflow, and low resistance at the glottis. Purring occurs when cats are contented, sick, or sleeping. It also provides the equivalent of complementary breaths during periods of shallow breathing.

• purse-string suture a suture pattern adapted to closing of the end of a hollow viscus or fixing tissue around a tube such as a catheter. Stitches are made into the wall completely surrounding the orifice but without entering the lumen of the viscus. The suture is tightened and tied with the free end of the viscus returned back inside the purse-string.

• purslane Portulacaoleracea.

  P-92.

  

  Thrombocytopenic purpura in a piglet

• pursley Portulacaoleracea.

• pursuit space the amount of space in a wild animal enclosure that is necessary to provide sufficient space for pursued animals to avoid their aggressors. The amount of space will vary widely depending on the species and on the individuals.

• purulence [pu′roo-l ns] the formation or presence of pus.

• purulent [pu′roo-l nt] containing or forming pus.

  • poultry p. synovitis swellings on the feet and in the limb joints causing lameness and spondylitis in fowls and turkeys. Caused by Staphylococcus aureus.

• puruloid [pu′roo-loid] resembling pus.

• pus [pus] a thick white-yellow or pale green, opaque exudate that is produced in infected tissues that contains cell debris, dead leukocytes (usually neutrophils), and protein rich fluid (liquor puris).

  • blue p. pus with a bluish tint, seen in certain suppurative infections, the color occurring as a result of the presence of an antibiotic pigment (pyocyanin) produced by Pseudomonas aeruginosa.
  • p. in milk indicates complete destruction of the mammary secretory tissue.

• push up term applied to that part of the total mixed ration that gets pushed too far for the animal to reach when being floor fed in a feeding alley through the stanchion system. Periodically, this is pushed up for access or is removed and fed to heifers.

• puss term of endearment addressed to a cat. Called also moggy.

• pushing disease a syndrome of compulsive walking and head pressing in cattle in southern Africa, caused by a number of hepatotoxic agents, especially Matricaria nigellaefolia. Called also stootsiekte.

• pustula [pus′tu-l ] pl. pustulae [L.] pustule.

• pustular [pus′tu-l r] pertaining to or of the nature of a pustule; consisting of pustules.

  • contagious viral p. dermatitis see contagious ecthyma.
  • infantile p. dermatosis see infantile pustular dermatosis.
  • ovine p. dermatitis see contagious ecthyma.
  • subcorneal p. dermatosis see subcorneal pustular dermatosis.
  • superficial p. dermatitis see superficial pustular dermatitis.
  • p. vulvovaginitis see infectious pustular vulvovaginitis.

• pustulation [pus″tu-la′sh n] the formation of pustules.

• pustule [pus′tūl] a small, elevated, circumscribed, pus-containing lesion of the skin or cornea; usually thin-walled and ruptures easily. Cutaneous pustules may be epidermal, intraepidermal, or subepidermal. The corneal lesions may be superficial or subcorneal.

• pustulosis [pus″tu-lo′sis] a condition marked by an eruption of pustules.

  • sterile eosinophilic p. a rare, pruritic pustular dermatitis of dogs characterized by numerous eosinophils found in the sterile lesions; there is often a peripheral eosinophilia. The cause is unknown.

• put down see euthanasia.

• put-to-sleep see euthanasia. Not recommended for use because of possible confusion with anesthetizing an animal.

• putamen [pu-ta′m n] the larger and more lateral part of the lenticular nucleus.

• putrefaction [pu″tr -fak′sh n] enzymatic decomposition of dead tissue by putrefactive bacteria (often saprophytic) with the production of foul-smelling compounds, such as hydrogen sulfide, ammonia, and mercaptans. Called also decomposition, rot.

• punctograph [punk′to-graf] an instrument for radiographic localization of foreign bodies.

• putrefy [pu′tr -fi] to undergo putrefaction.

• putrescence [pu-tres′ ns] the condition of undergoing putrefaction.

• putrescine [pu-tres′in] a polyamine first found in decaying meat; small quantities occur in most cells.

• putrid [pu′trid] rotten; putrified.

• Putti rasp a bone rasp with a curved, pointed rasp surface at both ends of this handheld metal instrument.

• putty a malleable carpenter’s material consisting of white lead and linseed oil. It is palatable to cattle and causes lead poisoning.

  • p. brisket see presternal calcification.

• PVA polyvinyl alcohol.

• PVC premature ventricular contraction or premature ventricular complex.

• PVCT posterior vena caval thrombosis.

• PVNT predictive value of a negative test.

• PVP polyvinylpyrrolidone. Called also povidone.

• PVP–I polyvinylpyrrolidone-iodone, or povidone–iodine.

• PVPT predictive value of a positive test; the proportion of disease-positive animals among those that test positive.

• Px abbreviation for prognosis; used in medical records.

• pyarthrosis [pi″ahr-thro′sis] suppuration within a joint cavity; suppurative arthritis.

• pycn(o)- see pykn(o)-.

• Pycnomonas a subgenus of trypanosomes. Includes Trypanosoma suis.

• Pycnosorus chrysanthus see Craspedia chrysantha.

• pye-dog mongrel dog.

• pyelectasis [pi″ -lek′t -sis] dilatation of the renal pelvis.

• pyelitis [pi″ -li′tis] inflammation of the renal pelvis, the outer basin-like portion of the kidney at the attachment of the ureter.

  • cystic p. pyelitis with formation of multiple submucosal cysts.
  • p. glandularis the pelvic mucosa is modified to cylindrical epithelium and the formation of glandular acini.

• pyel(o)- word element. [Gr.] relationship to the renal pelvis.

• pyelocaliectases [pi″ -lo-kal″e-ek′t -ses] dilatation of the renal pelvis and calices.

• pyelocentesis [pi″ -lo-sen-te′sis] aspiration of fluid from the renal pelvis, usually for diagnostic purposes.

• pyelocystitis [pi″ -lo-sis-ti′tis] inflammation of the renal pelvis and bladder.

• pyelogram [pi′ -lo-gram] the images produced by pyelography. Commonly radiography or CT pyelography.

• pyelography [pi″ -log′r -fe] imaging of the kidney and ureter after injection of a contrast medium, introduced by the intravenous, antegrade or retrograde method. Called also intravenous pyelography (IVP) or exretory urogram if the contrast is injected intravenously.

  • antegrade p. imaging of the renal pelvis and ureter following introduction of contrast to the renal pelvis via ultrasound guidance.
  • retrograde p. imaging of the ureter and renal pelvis after introduction of contrast medium through the ureter and bladder.

• pyelointerstitial [pi″ -lo-in″tr-stish′ l] pertaining to the interstitial tissue of the renal pelvis.

• pyelolithotomy [pi″ -lo-lľ-thot′ -me] incision of the renal pelvis for re-moval of calculi.

• pyelonephritis [pi″ -lo-n -fri′tis] inflammation of the kidney and renal pelvis usually as a result of bacterial infection ascending from the lower urinary tract. Typically, the resulting inflammation produces irregularlydistributed segmental wedges of inflammation radiating out to the cortex from the inflamed pelvis. These foci tend to be more numerous at the poles of the kidney. See also pyelitis and nephritis.

  • contagious bovine p. see contagious bovine pyelonephritis.
  • porcine p. see cystitis-pyelonephritis of sows.

• pyelonephrosis [pi″ -lo-n -fro′sis] any disease of the kidney and its pelvis.

• pyelopathy [pi″ -lop′ -the] any disease of the renal pelvis.

• pyeloplasty [pi′ -lo-plas″te] plastic repair of the renal pelvis.

• pyeloplication [pi″ -lop″li-ka′sh n] reduction in size of a dilated renal pelvis by surgical infolding of its walls.

• pyelostomy [pi″ -los′t -me] the operation of forming an opening in the renal pelvis for the purpose of temporarily diverting the urine from the ureter.

• pyelotomy [pi″ -lot′ -me] incision of the renal pelvis.

• pyelovenous [pi″ -lo-ve′n s] pertaining to the renal pelvis and renal veins.

• pyemesis [pi-em′ -sis] the vomiting of pus.

• pyemia [pi-e′me- ] septicemia in which secondary foci of suppuration occur and multiple abscesses are formed.

  • arterial p. a form due to the dissemination of septic emboli from the heart.
  • cryptogenic p. that in which the source of infection is in an unidentified tissue.

• pyemic [pi-e′mik] pertaining to or emanating from pyemia.

  • p. hepatitis disease caused by Yersinia pseudotuberculosis in sheep. Characterized by septicaemia and necrotic foci in liver, spleen, and lymph nodes and fibrinohemorrhagic enteritis.

• Pyemotes a genus of mites; P. tritici (straw-itch mite) and P. ventricosus (harvest mite) can cause transitory dermatitis on animals eating infested feeds.

• pyencephalus [pi″en-s f′-l s] abscess of the brain.

• pygal [pi′g l] pertaining to the buttocks.

• pygoamorphus [pi″go- -mor′f s] asymmetrical conjoined twins, in which the parasite is an amorphous mass attached to the sacral region of the autosite.

• pygodidymus [pi″go-did′ľ-m s] a fetus with double hips and pelvis.

• pygomelus [pi-gom′ -l s] a fetus with a supernumerary limb or limbs attached to or near the buttocks.

• pygopagus [pi-gop′ -g s] conjoined twins fused in the sacral region.

• pygostyle [pi′go-stīl] a bony termination of the vertebral column in birds formed by fusion of the last four to eight vertebrae. The tail feathers are attached to its fascia so that it is very important in flight. Called also plowshare bone or rump post.

• pyknic [pik′nik] having a short, thick, stocky build.

• pykn(o)- word element. [Gr.] thick, compact, frequent.

• pyknocyte [pik″no-sīt] a distorted and contracted, occasionally spiculed erythrocyte.

• pyknocytosis [pik″no-si-to′sis] conspicuous increase in the number of pyknocytes.

• pyknometer [pik-nom′ -t r] an instrument for determining the specific gravity of fluids.

• pyknomorphous [pik″no-mor′f s] a cell that stains deeply due to the compact arrangement of its stainable contents.

• pyknosis [pik-no′sis] the process of nuclear shrinkage and chromatin condensation occurring in cells undergoing apoptosis or necrosis.

• pyle- [pīl] word element. [Gr.] portal vein.

• pylephlebectasis [pi″le-fl -bek-ta′sis] dilatation of the portal vein.

• pylephlebitis [pi″le-fl -bi′tis] inflammation of the portal vein.

• pylethrombophlebitis [pi″le-throm″bo-fl -bi′tis] thrombosis and inflammation of the portal vein.

• pylethrombosis [pi″le-throm-bo′sis] thrombosis of the portal vein.

• pylorectomy [pi″lo-rek′t -me] excision of the pylorus.

• pyloric [pi-lor′ik] pertaining to the pylorus or to the pyloric part of the stomach.

  • antral p. hypertrophy syndrome acquired narrowing of the pyloric antrum caused by hypertrophy of the circular smooth muscle and mucosa; occurs most commonly in mature dogs of small breeds. Obstruction to gastric emptying causes chronic vomiting. Called also chronic hypertrophic pyloric gastropathy.
  • p. antrum the part of the stomach cavity just cranial (oral) to the pylorus.
  • p. dysfunction the usual effect is to delay gastric emptying. See pyloric achalasia, pyloric obstruction (below).
  • p. gastropathy chronic hypertrophic pyloric gastropathy.
  • p. gland situated in the pyloric region of the stomach and secreting gastrin and mucus. The secretion is slightly alkaline.
  • p. obstruction may be functional due to spasm or achalasia, or physical due to foreign body, e.g., phytobezoar, or external compression by, e.g., lipoma or fat necrosis or tumor or cicatrical contraction. Clinical signs are vomiting, distress due to gastric dilatation, possibly visible abdominal enlargement. In ruminants, gross distention of abdomen, rumen contents running from nose, scant feces. In dogs and cats, delayed gastric emptying usually causes vomiting, sometimes characteristically projectile, of undigested food. In foals as a consequence of gastric ulceration and cicatricial scarring of the pylorus, with signs of excessive salivation, bruxism, and failure to thrive.
  • p. outflow failure achalasia of the pylorus with obstruction to the flow of ingesta into the intestine; impaction of material in the abomasum follows; pyloric ulcer a common sequel.
  • p. spasm see pyloric achalasia (above).
  • p. stenosis, congenital p. hypertrophy usually a congenital lesion in dogs, particularly the brachycephalic breeds, that causes vomiting and poor growth from weaning age. Occasionally hypertrophy of the pyloric sphincter may be acquired.

• pylor(o)- word element. [Gr.] relationship to the pylorus.

• pylorodiosis dilatation of a pyloric stricture with the fingers during a surgical operation.

• pyloroduodenitis [pi-lor″o-du″o-de-ni′tis] inflammation of the pyloric and duodenal mucosa.

• pylorogastrectomy [pi-lo″ro-gas-trek′t -me] excision of the pylorus and adjacent portion of the stomach.

• pyloromyotomy [pi-lor″o-mi-ot′ -me] incision of the longitudinal and circular muscles of the pylorus in order to treat congenital pyloric stenosis.

  • Fredet–Ramstedt p. see Ramstedt operation.

• pyloroplasty [pi-lor′o-plas″te] plastic surgery of the pylorus, especially for pyloric stricture, to provide a larger communication between the stomach and duodenum.

  • Finney p. enlargement of the pyloric canal by establishment of an inverted U-shaped anastomosis between the stomach and duodenum after longitudinal incision.
  • Fredet–Ramstedt p. see Ramstedt operation.
  • Heineke–Mikulicz p. enlargement of a pyloric stricture by incising the pylorus longitudinally and suturing the incision transversely.
  • Y-U antral advancement flap p. an antral flap is created and advanced over the incision through the pylorus.

    P-93.

    

    Chin pyoderma in a dog

• pyloroscopy [pi″lor-os′k -pe] endoscopic examination of the pylorus and pyloric sphincter, typically during gastroscopy.

• pylorospasm [pi-lor′o-spaz″ m] spasm of the pylorus or of the pyloric portion of the stomach.

• pylorostenosis [pi-lor″o-st -no′sis] pyloric stenosis.

• pylorostomy [pi″lor-os′t -me] surgical formation of an opening through the abdominal wall into the stomach near the pylorus.

• pylorotomy [pi″lor-ot′o-me] incision of the pylorus.

• pylorus [pi-lor′ s] the distal aperture of the stomach or abomasum, opening into the duodenum. The term pylorus is variously used to mean the pyloric part of the stomach, and the pyloric antrum, canal, opening or sphincter. A ring of muscles, the pyloric sphincter, serves as a ‘gate’, closing the opening from the stomach to the intestine. It opens periodically, allowing the contents of the stomach to move into the duodenum. See also pyloric.

• py(o)- word element. [Gr.] relationship to pus.

• pyoarthritis pyarthrosis.

• pyocele [pi′o-sēl] a collection of pus, as in the scrotum.

• pyocephalus [pi″o-sef′ -l s] the presence of purulent fluid in the cerebral ventricles.

• pyochezia [pi″o-ke′ze- ] the presence of pus in the feces.

• pyococcus [pi″o-kok′ s] a pus-forming coccus.

• pyocolpocele [pi″o-kol′po-sēl] a vaginal tumor or cyst containing pus.

• pyocolpos [pi″o-kol′pos] pus in the vagina.

• pyocyanic [pi″o-si-an′ik] pertaining to blue pus, or to Pseudomonas aeruginosa.

• pyocyanin [pi″o-si′ -nin] a blue-green antibiotic pigment produced by Pseudomonas aeruginosa; it gives the color to ‘blue pus’.

• pyocyins [pi″o-si′ ns] antibacterial proteins produced by strains of Pseudomonas aeruginosa; used in strain typing.

• pyocyst [pi′o-sist] a cyst containing pus.

• pyoderma [pi″o-dur′m ] any purulent skin disease. Includes pustule, pimple, acne, impetigo, and furunculosis.

  P-94.

  

  Juvenile pyoderma in a German shorthaired pointer puppy

  P-95.

  

  Mucocutaneous pyoderma

  • callus p. see callus pyoderma.
  • chin p. varying degrees of folliculitis and furunculosis of the chin and adjacent muzzle and lips; often seen as comedones, papules, and pustules and referred to as canine acne in young adults of short-haired breeds. Some cases may be precipitated by local trauma from chew toys or pressure when recumbent. See also canine acne.
  • contagious porcine p. see contagious porcine pyoderma.
  • deep p. bacterial infections involving the dermis and often subcutaneous tissues. There may be systemic illness.
  • dry p. see zinc-responsive dermatosis.
  • fold p. see fold dermatitis.
  • p. gangrenosum a rare skin disease in dogs of unknown etiology characterized by multiple necrotic, draining crateriform ulcers predominantly over the trunk.
  • interdigital p. infection of the interdigital skin in dogs; may be associated with trauma, Demodex canis infestation, or foreign bodies such as grass seeds.
  • juvenile p. a sterile, pustular skin disease on the face and head and sometimes ears, anus, and prepuce, in one or more puppies of a litter, usually around weaning age. Dachshunds, Golden retrievers, and Gordon setters appear to be predisposed. There is often fever, anorexia, and lymphadenopathy, particularly of submandibular lymph nodes that may form abscesses and drain, hence the alternative name of puppy strangles.
  • Staphylococcus spp. are frequently cultured from affected skin, but the etiology of the disease is unclear. Called also juvenile cellulitis, and juvenile sterile granulomatous dermatitis and lymphadenitis.
  • mucocutaneous p. erythema and crusting that can progress to erosions, ulcerations and fissures on the lip margins and perioral skin of dogs; German shepherd dogs are predisposed. Nares, eyelids, vulva, prepuce, and anus are also sometimes involved.
  • nasal p. a deep bacterial folliculitis and furunculosis on the dorsum of the nose in dogs, particularly German shepherd dogs, Bull terriers, Collies, and Pointers. Trauma (rubbing, digging) may be a factor in the etiology.

    P-96.

    

    Nasal pyoderma

  • perianal p. see perianal fistula.
  • pressure point p. see pressure points.
  • skin-fold p. see fold dermatitis.
  • superficial pustular p. see impetigo.
  • surface p. see acute moist dermatitis.
  • tail fold p. see fold dermatitis.

• pyodermatitis [pi″o-dur-me-ti′tis] pyoderma.

• pyodermia [pi″o-dur′me- ] pyoderma.

• pyogenesis [pi″o-jen′ -sis] the formation of pus.

• pyogenic [pi″o-jen′ik] producing pus.

  • p. dermatitis pyoderma.
  • p. gingival granuloma a bright red or blue mass on the gum, caused by chronic inflammation. Composed of vascular granulation tissue.
  • p. spondylitis vertebral osteomyelitis.

• pyogranuloma [pi″o-gran″u-lo′m ] an inflammatory process in which there is infiltration of polymorphonuclear cells into a more chronic area of inflammation characterized by mononuclear cells, macrophages, lymphocytes, and possibly plasma cells.

  • sterile p. syndrome see idiopathic sterile granuloma syndrome.

• pyohemia [pi″o-he′me- ] pyemia.

• pyohemothorax [pi″o-he″mo-thor′aks] pus and blood in the pleural cavity.

• pyohydronephrosis [pi″o-hi″dro-n -fro′sis] the accumulation of pus and urine in the kidney.

• pyoid [pi′oid] resembling or like pus.

• pyolabyrinthitis [pi″o-lab″ -rin-thi′tis] inflammation with suppuration of the labyrinth of the ear.

• pyometra [pi″o-me′tr ] an accumulation of pus within the uterus. In the bitch, it is a distinct disease syndrome associated with cystic endometrial hyperplasia and usually infection by a variety of bacteria, especially Escherichia coli, occurring during diestrus. Clinical signs may include abdominal enlargement, purulent vaginal discharge if the cervix is open, polyuria, polydipsia, and a systemic response, which is more severe if the cervix is closed. An immune-mediated glomerulonephritis may also occur. In cattle, pyometra is part of the complex of puerperal metritis, clinical endometritis, and subclinical endometritis, the most common forms of genital diseases in dairy cows that delay the complete regeneration of endometrium and impair reproductive performance. Pyometra is an inflammatory disease, which develops after the first ovulation in the presence of an active luteal tissue. As a result of luteal progesterone production, the cervix is closed, and mucopurulent or purulent exudate accumulates in the uterine cavity. Diagnosis is by per-rectal palpation and/or transrectal ultrasonography. post-coital p. Tritrichomonas foetus veneral infection in cattle is characterized by embryonic and early fetal death and post-coital pyometra.

  • stump p. infection in the remaining portion of uterus after ovariohysterectomy.

• pyometritis [pi″o-m -tri′tis] purulent inflammation of the uterus. See also pyometra.

  P-97.

  

  Lateral abdominal radiograph of a dog with pyometra. Note the enlarged uterus in the caudoventral abdomen displacing viscera cranially and dorsally

• pyomyositis [pi″o-mi″o-si′tis] purulent myositis characterized by suppurating masses in the muscle.

• pyonephritis [pi″o-n -fri′tis] purulent inflammation of the kidney.

• pyonephrolithiasis [pi″o-nef″ro-lľ-thi′ -sis] pus and calculi in the kidney.

• pyonephrosis [pi″o-n -fro′sis] suppurative destruction of the renal parenchyma, with total or almost complete loss of kidney function.

• pyo-ovarium [pi″o-o-va′re- m] an abscess of the ovary.

• pyopericarditis [pi″o-per″ľ-kahr-di′tis] purulent pericarditis.

• pyopericardium [pi″o-per″ľ-kahr′de- m] pus in the pericardium.

• pyoperitoneum [pi″o-per″ľ-to-ne′ m] pus in the peritoneal cavity.

• pyoperitonitis [pi″o-per″ľ-to-ni′tis] purulent inflammation of the peritoneum.

• pyophthalmitis [pi″of-th l-mi′tis] purulent inflammation of the eye.

• pyophysometra [pi″o-fi″so-me′tr ] pus and gas in the uterus.

• pyopneumocholecystitis [pi″o-noo″mo-ko″l -sis-ti′tis] distention of the gallbladder, with the presence of pus and gas.

• pyopneumohepatitis [pi″o-noo″mo-hep″ -ti′tis] abscess of the liver with pus and gas in the abscess cavity.

• pyopneumopericardium [pi″o-noo″mo-per″ľ-kahr′de- m] pus and gas in the pericardium.

• pyopneumoperitonitis [pi″o-noo″mo-per″ľ-to-ni′tis] peritonitis with the presence of pus and gas.

• pyopneumothorax [pi″o-noo″mo-thor′aks] pus and air or gas within the pleural cavity.

• pyopyelectasis [pi″o-pi″ -lek′t -sis] dilatation of the renal pelvis with pus.

• pyorrhea [pi″o-re′ ] an obsolete term describing discharge of pus from the periodontium.

• pyosalpingitis [pi″o-sal″pin-ji′tis] purulent salpingitis.

• pyosalpingo-oophoritis [pi″o-sal-ping″go-o″of- -ri′tis] purulent inflammation of the uterine tube and ovary.

• pyosalpinx [pi″o-sal′pinks] an accumulation of pus in a uterine tube.

• pyosepticemia [pi″o-sep″tľ-se′me- ] pyemia and septicemia in the one animal.

• pyostatic [pi″o-stat′ik] arresting suppuration (formation or discharge of pus); an agent that arrests suppuration.

• pyothorax [pi″o-tho′raks] an accumulation of pus in the thorax. Commonly seen in cats, caused by a variety of bacteria, especially Pasteurella, Staphylococcus, Nocardia, Porphyromonas, Prevotella, and Bacteroides spp. Large amounts of pleural fluid accumulate. Affected cats frequently show a rapid development of dyspnea and cyanosis, and often die suddenly. See also empyema.

• pyotraumatic dermatitis [pi″o-tr -mat′ik dur″m -ti′tis] a focal, superficial bacterial infection of the skin, usually caused by self-trauma, i.e., scratching, rubbing, biting. In dogs, ectoparasites, otitis, anal sacculitis, and pruritic skin diseases are common precipitating causes. Affected skin is moist with a covering of matted haircoat and dried exudate. Staphylococcus spp. are usually present. Called also acute moist dermatitis, ‘hot spots’.

• pyoureter [pi″o-u-re′t r] pus in the ureter.

• Pyramicocephalus phocarum a cestode parasite belonging to the family Diphyllobothriidae, found in seals.

• pyramid [pir′ -mid] a pointed or cone-shaped structure or part.

  • p. breed structure a standard format for a multiple herd system comprising a breed structure; headed by an open or closed nucleus, a second tier of multiplier herds, and a terminal tier of commercial herds which produce the end-product to be marketed. The nucleus, perhaps one herd, produces all of the basic genetic material and supplies breeding stock to the multiplier herds which have the prime role of multiplying the progeny for supply to commercial herds who produce the end product. The entire system is under the control of one organization. Ideally suited to the pig industry.
  • p. of cerebellum pyramid of vermis.
  • p. of light a triangular reflection seen upon the tympanic membrane.
  • malpighian p’s renal pyramids.
  • p’s of the medulla oblongata either of two rounded masses, one on either side of the median fissure of the medulla oblongata containing the pyramidal tracts.
  • renal p’s the conical masses constituting the medulla of certain kidneys, the base toward the cortex and culminating at the summit in the renal papilla.

• pyramidal [pľ-ram′ľ-d l] shaped like a pyramid.

  • p. disease abnormal growth of the wall of the hoof in the horse in which the vertical midline of the front of the hoof bulges, causing lameness. Caused by fracture of the extensor process of the third phalanx or by low ringbone.
  • p. nervous system pyramidal-shaped nerve cells in the cerebral cortex and their efferent neurons to skeletal muscles.
  • p. tracts collections of motor nerve fibers arising in the brain and passing down through the spinal cord to motor cells in the ventral horns.

• pyramiding in the shell of captive raised tortoises, the scutes raise up over time and take on a pyramid or tent-like appearance. Generally attributed to secondary nutritional hyperparathyroidism, but excessive dietary protein and low environmental humidity are also believed to cause the condition,

• pyramis [pir′ -mis] pl. pyramides [Gr.] pyramid.

• pyran [pi′ran] a cyclic compound in which the ring consists of five carbon atoms and one oxygen atom and contains two double bonds.

• pyranose [pir′ -nōs] a six-membered ring structure formed by the reaction of the carbonyl group and a hydroxy group of a sugar to form a hemiacetal.

• pyrantel [pľ-ran′t l] a broad-spectrum anthelmintic of low toxicity, used as the pamoate and tartrate salts; has been used extensively in dogs and cats; used to a lesser extent in horses.

• pyrazines [pľ′r -zēn] volatile compounds with a strong odor; contribute part of the odor of meat.

• pyrazinecarboxamide pyrazinamide.

• pyrazolone derivatives [pir-az′o-lōn] a group of agents that have analgesic and antipyretic actions. They include phenylbutazone and dipyrone.

• pyrectic [pi-rek′tik] 1. pertaining to fever; feverish. 2. a fever-inducing agent.

• Pyrenean associated with the Pyrenean region in northern Spain.

  • P. goat France and Spain, dark brown or black with pale belly and feet, dual-purpose goat, longhaired, horned, or polled.
  • P. mastiff a very large (180 lb) mastiff-type dog with a heavy, long white coat with colored patches.
  • P. mountain dog see Great Pyrenees.
  • P. shepherd, sheepdog a herding dog from the Pyrenees Mountains, smaller (18–32 lb) than others from that region. The thick, long or medium coat is coarse to woolly and most commonly fawn. There are rough-faced and smooth-faced varieties. The tail is docked, naturally very short, or long. Called also ‘Pyr shep’, Pyrenees sheepdog.

• pyrethrins [pi-reth′rinz] the active insecticidal agents in pyrethrum from plant sources (Chrysanthemum sp.); synthetic pyrethrins are widely used in commercial insecticides. Natural and synthetic pyrethrins can cause systemic or cutaneous hypersensitivity reactions.

• pyrethroids [pi-reth′roid] synthetic substances with activity similar to the naturally occurring pyrethrins. They include cypermethrin, cyhalothrin, deltamethrin, flumethrin, permethrin, fenvalerate.

• pyrethrolone a natural pyrethrin, obtained by the hydrolysis of pyrethrin, used as an insecticidal agents; pyrethrin.

• pyrethrum [pi-re′thr m] common name for plants formerly in the genus Pyrethrum and now classified as either Chrysanthemum or Tanacetum; also the name of a natural insecticide derived from the dried flower heads of Chrysanthemum sp. Called also Dalmatian or Persian insect powder. See also pyrethrins.

• pyretic [pi-ret′ik] pertaining to fever.

• pyretogenesis [pi″r -to-jen′ -sis] the origin and causation of fever.

• pyretogenous [pi″r -toj′-n s] 1. caused by high fever. 2. pyrogenic.

• pyretotherapy [pi″r -to-ther′ -pe] 1. treatment by artificially increasing the animal’s body temperature. 2. the treatment of fever.

• pyrexia [pi-rek′se- ] a fever, or febrile condition. Can be said to be present if body temperature exceeds the normal range for the particular age and species: horse 102.0°F (39.0°C), cattle 103.0°F (39.5°C), pig 103.5°F (40.0°C), sheep 104.0°F (40.0°C), goat 105.0°F (40.5°C), llama, alpaca 102.0°F (39.0°C), dog and cat 102.0°F (39.0°C). Called also fever. See also hyperthermia.

  • p.–pruritus–hemorrhage syndrome a silage-associated syndrome in dairy cattle thought to be due to use of a chemical aid in the making of ensilage, possibly via the intervention of a mycotoxin, possibly citrinin. Clinically characterized by widespread pruritic dermatitis, fever, and mucosal petechiation.

• pyridine [pir′ľ-dēn] 1. a substance derived from coal tar and also from tobacco and various organic materials. Used in industry as a solvent and in the synthesis of organic compounds. 2. any of a group of substances homologous with normal pyridine. The pyridines are serious poisons causing damage to most organs especially nervous and respiratory systems and skin.

• pyridostigmine [pir″ľ-do-stig′mēn] a cholinesterase inhibitor; used in the treatment of myasthenia gravis and as an antidote to nondepolarizing muscle relaxants, such as tubocurarine.

• pyridoxal, pyridoxaldehyde [pir″ľ-dok′s l] a natural form of vitamin B₆ found in green plants.

  • p. phosphate form of vitamin B₆ that is active in the body; a major coenzyme involved in amino acid metabolism; also required for the synthesis of heme and the neurotransmitters dopamine and γ- aminobutyric acid (GABA).

• pyridoxamine [pir″ľ-doks′ -mēn] one of the three natural forms of vitamin B₆.

  • p. phosphate cofactor involved in the metabolism of amino acids and other related compounds via interconversion with pyridoxal 5’ phosphate (PLP).

• pyridoxine one of the forms of vitamin B_6; the other forms of vitamin B6 are pyridoxal and pyridoxamine. Nutritional deficiency is not known to occur under natural conditions in animals.

  • p. shampoos marketed for use in treating seborrheic skin conditions in dogs.

• pyriform [pir′ľ-form] pear-shaped.

  • p. apparatus pair of triangular structures in the eggs of anoplocephalid tapeworms surrounding the oncosphere.
  • p. lobe a swelling on the ventral surface of the brain, made up of the combined lateral olfactory gyrus and the hippocampal gyrus.

• pyrilamine [p -ril′ -mēn] an ethylenediamine histamine type 1 (H₁)-receptor antagonist, used topically and systemically in the treatment of allergic disorders. Called also mepyramine.

• pyrimethamine [pir″ľ-meth′ -mēn] a folic acid antagonist used in combination with sulfonamides in the treatment of toxoplasmosis and avian coccidiosis.

• pyrimidine [p -rim′ľ-dēn] an organic compound that is the fundamental form of the pyrimidine bases, including uracil, cytosine, and thymine.

• pyriminil see Vacor.

• pyriprole an analog of fipronil; approved in the EU for use as a spot-on treatment in the control of flea and tick infestation in dogs.

• pyriproxyfen an ovicidal and larvicidal carbamate used topically and as a spot-on treatment in the control of fleas on dogs and cats. Mimics the juvenile growth hormone of insects and disrupts development.

• pyr(o)- word element. [Gr.] fire, heat; (in chemistry) produced by heating.

• pyrocatechol [pi″ro-kat′ -kol] see catechol.

• pyrogen [pi′ro-j n] an agent that causes fever.

  • endogenous p. (EP) the mediator of fever, produced by polymorphonuclear leukocytes, monocytes, and macrophages.
  • exogenous p. lipopolysaccharide and other substances produced by pathogenic microorganisms.

• pyrogenic reaction [pi″ro-jen′ik] one causing fever.

• pyroglobulinemia [pi″ro-glob″u-lin-e′me- ] the presence in the blood of an abnormal globulin constituent that is precipitated by heat.

• pyroglutamic acid [pi″ro-gloo-tam′ik] see 5-oxoproline.

• pyrolysis [pi-rol′ľ-sis] decomposition by heating; said of organic materials.

• pyrometer [pi-rom′ -t r] instrument for measuring the intensity of heat when this is beyond the range of the mercury thermometer.

• pyronine [pi′ro-nēn] a red aniline histological stain.

• pyroninophilic [pi″ro-nin″o-fil′ik] having an affinity for pyronine.

  • p. cell contains large quantities of RNA stainable with pyronine. Called also immunoblast.

• pyrophosphatase [pi″ro-fos′f -tās] any enzyme that catalyzes the hydrolysis of pyrophosphate linkages, so that one phosphoryl group remains on each of the two products.

  • inorganic p. an enzyme that splits pyrophosphate into two phosphate ions.

• pyrophosphate [pi″ro-fos′fāt] any salt of pyrophosphoric (diphosphoric) acid.

• pyrophosphoric acid [pi″ro-fos-for′ik] a dimer of phosphoric acid, H₄P₂O₇. Called also diphosphoric acid.

• pyrotic [pi-rot′ik] caustic; burning.

• pyroxylin [pi-rok′s -lin] a product of the action of a mixture of nitric and sulfuric acids on cotton, consisting chiefly of cellulose tetranitrate; a necessary ingredient of collodion.

• pyrrole [pēr′ol] a basic, heterocyclic substance with a nitrogen-containing 5-membered ring, obtained by destructive distillation of various animal substances. Critical components in the synthesis of porphyrins.

• pyrrolic metabolites [pľ-rol′ľk m -tab′o-līts] highly reactive products of hepatic enzymic metabolism of ingested pyrrolizidine alkaloids from plants that bind to cell macromolecules and lead to cell damage. These metabolites persist for long periods in liver and have been used as the basis for diganosis of pyrrolizidine alkaloidosis.

• pyrrolidine [pľ-rol′ľ-din] a simple base obtained from tobacco or prepared from pyrrole. Called also tetrahydropyrrole.

• pyrrolizidine [pľ-ro-liz′ľ-dēn] a specific chemical configuration that is common to a number of naturally occurring compounds called the pyrrolizidine alkaloids. Common plant sources are in the genera Crotalaria, Echium, Heliotropium, Senecio.

  • p. alkaloidosis the disease caused by poisoning with pyrrolizidine alkaloids. The hepatic lesion tends to be chronic and is characterized by necrosis, megalocytosis of hepatocytes due to inhibition of mitosis, biliary ductular, proliferation, vasculitis, and perivenous fibrosis. Lesions are most severe in the liver and result in various clinical signs including jaundice, photosensitization, and hepatic encephalopathy, and sometimes hemolysis. Some alkaloids cause lung damage characterized by edema, fibrosis, alveolar epithelialization, and emphysema, e.g., jaagsiekte. Megalocytosis also occurs in the kidney, and there may be extensive nephrosis. Carcinogenesis is a feature in laboratory animals. An incidental pathogenesis is a concurrent chronic copper poisoning causing the disease toxemic jaundice.
  • p. alkaloids alkaloids produced by plants, about half of which are toxic. Toxic alkaloids are usually esters of retronecine or heliotridine and have known specific structural features. Toxic examples include senecionine, jacobine, monocrotaline, spectabiline, heliotrine and lasiocarpine. They often occur in plants as the less toxic N-oxide forms. These can be converted to the toxic free bases by intestinal microbes or liver enzymes. Cause pyrrolizidine alkaloidosis (see above). Common plant sources are in the genera Crotalaria, Echium, Heliotropium, Senecio. See also pyrrolic metabolites.

• Pyrus malus see Malus sylvestris.

• pyruvate [pi′roo-vāt] a salt, ester or anion of pyruvic acid. The term is used interchangeably with pyruvic acid. Pyruvate is the end product of glycolysis and may be metabolized in the body anerobically to lactate or after transport into mitochondria to acetyl CoA. In yeast it is metabolized to ethanol.

  • p. carboxylase an enzyme that catalyzes the conversion of pyruvate to oxaloacetic acid and has a regulatory role in gluconeogenesis.
  • p. dehydrogenase an enzyme actively concerned in the decarboxylation of pyruvate to acetyl CoA and CO₂. A component enzyme of the pyruvate dehydrogenase complex.
  • p. dehydrogenase complex complex consisting of three enzymes responsible for the conversion of pyruate into acetyl CoA in a decarboxylation reaction. Requires the co-factors thiamine pyrophosphate (TPP), lipoic acid, NAD⁺, and FAD.
  • p. dehydrogenase phosphatase deficiency an inherited autosomal recessive trait in Clumber and Sussex spaniel dogs; one of the mitochondrial myopathies. A null mutation in pyruvate dehydrogenase phosphatase 1 results in exercise intolerance and post-exercise collapse in affected dogs.
  • p. kinase (PK) a glycolytic pathway enzyme that catalyzes the formation of pyruvate and one molecule of ATP by the transfer of a phosphate group from phosphoenolpyruvate (PEP) to ADP. A deficiency of the enzyme is inherited as an autosomal recessive trait in humans and occurs also in Beagles, Basenjis, andWest Highland white terriers and causes a nonspherocytic anemia. It also occurs as an autosomal recessive trait in Abyssinian, Somali, and some domestic shorthair cats.
  • p. transaminase see alanine aminotransferase.

• pyruvic acid [pi-roo′vik] a compound formed in the body in metabolism of carbohydrate; also formed by dry distillation of tartaric acid. Used synonymously with pyruvate.

• pyruvic kinase see pyruvate kinase.

• pythiosis [pith″e-o′sis] infection by Pythium insidiosum; an uncommon disease of cattle, horses, companion animals, and humans. Occurs most often in the southern US, but has been reported from many other countries in regions with similar climatic conditions and opportunities for exposure to standing water. Usually ulcerative and granulomatous cutaneous lesions that do not invade adjacent muscular tissues, but occasionally occurs as systemic disease. Called also equine espundia in Colombia.

  • canine p. most often occurs in large breed dogs as either a gastrointestinal or cutaneous infection, depending on the method of exposure. In the gastrointestinal form, there is a severe, segmental granulomatous enteritis and lymphadenopathy with chronic diarrhea, vomiting, weight loss, and depression. In cutaneous and subcutaneous pythiosis, there are single or multiple ulcerated and draining nodules and masses.
  • equine p. see swamp cancer.

• Pythium insidiosum [pith′e- m] previously called Hyphomyces destruens, obsolete synonym P. destruens; the cause of pythiosis in dogs, cattle, and horses. Previously classified as fungus, but now regarded as one of the oomycetes, members of a separate kingdom, either Stramenopila or Chromista. Disease in horses is also referred to as swamp cancer.

• python non venomous snakes of the family Pythonidae, native to Africa, Australia, and Asia. Most are large, with a distinct neck. Common as pets.

  • ball p. constricting snake (Python regius), ranging from 4 to 6 ft long; popular as pets because of their manageable size and docile nature. Curling up into a ball with the head buried in the middle is typical defensive behavior and the source of the name. Called also royal python.
  • Burmese p. a very large snake (averaging 10–12 ft in length), popular in the pet trade. Has escaped in Florida and is becoming a major pest
  • carpet p. (Morelia spp.) a medium-sized, non-venomous, arboreal snake native to Australia and New Guinea; very popular as pets. Various subspecies exist, inlcuding the diamond python (M. spilota spilota).
  • children’s p. (Antaresia childreni) a small, non-venomous python native to northern Australia; adaptable to captivity, they generally have a placid nature, and their small size makes them popular as pets. A nocturnal species, named after zoologist John Children, not because they are kept by children.
  • diamond p. (Morela spilota spilota) a medium-sized snake, native to Australia and New Guinea, with distinctive yellow and black, diamondshaped markings. Called also diamond snake.
  • royal p. see ball python (above).

• pyuria [pi-u′re- ] white blood cells (pus) in the urine.

• PZI protamine zinc insulin.

• pyrazinamide [pir″ -zin′ -mīd] an antibacterial agent used for the oral treatment of tuberculosis in humans. Also used in a biochemical test for the identification of mycobacteria.