Abstract
Three cows of the Swedish Red and White Breed (SRB) were used in the experiment. Cow no. 1 pregnant for 247 days, was given 20 mg dexamethasone twice with an interval of 48 hrs. Cows nos. 2 and 3, each pregnant for 254 days, received 20 mg of dexamethasone twice with an interval of 24 hrs. The cows delivered normal living calves 153, 138 and 137 hrs., respectively, after the second injection of dexamethasone. Blood samples were drawn from the jugular vein every third hour during the experimental period and the samples were analyzed for estrone, progesterone and 15-keto-13,14-dihydroprostaglandin F2α. Following the dexamethasone injections there was a continuous increase in the blood plasma levels of estrone followed by a sharp decrease in conjunction with parturition. The blood plasma level of progesterone showed a slow but continuous decrease until about 24 hrs. before delivery when a marked drop occurred. The levels of the prostaglandin metabolite increased gradually until about 24 hrs. prior to delivery. This was followed by an abrupt rise, and high levels of the prostaglandin metabolite were recorded for up to four days following parturition. It is concluded that the estrone increase preceded that of the prostaglandin metabolite and that the final drop in the progesterone was synchronous with the final rise of the prostaglandin metabolite level.
Keywords: prostaglandin release, estrone, progesterone, dexamethasone induced parturition, bovine
Sammanfattning
Tre dräktiga kor av SRB-ras ingick i försöket. Ko nr. 1, dräktig 247 dagar, gavs 20 mg dexamethason i.m. med 48 timmars intervall. Ko nr. 2 och 3 gavs samma dos i.m. men med 24 timmars intervall. Behandlingen resulterade i prematur förlossning 153, 138 och 137 timmar efter sista Injektionen. Under försöksperioden uttogs blod- prover var 3:e tirnma. Blodproverna analyserades med avseende påöstron, progesteron samt huvudmetaboliten till prostaglandin F2α hos ko, 15-keto-l3,14-dihydroprostaglandin F2α. Den perifera blodplasma- koncentrationen av östron ökade efter dexametasonbehandlingen från cirka 0.5 ng/ml till maximalt 3–5 ng/ml som uppmättes under 24-tim- marsperioden närmast före förlossningen. Efter partus sjönk perifera blodplasmanivån av Östron snabbt till värden under 0.5 ng/ml. Perifera blodplasmanivån av progesteron sjönk långsamt och gradvis från cirka 5–8 ng/ml till cirka 3 ng/ml vilket uppmättes ungefär 24 timmar före förlossningen. Därefter sjönk progesteronnivån kraftigt och värden nära noli registrerades strax före och i samband med förlossningen. Koncentrationen av 15-keto-l 3,14-dihydroprostaglandin F2α ökade långsamt fram till ungefär 24 timmar före förlossningen då en snabb ökning av koncentrationen noterades samtidigt med den kraf- tiga progesteronsänkningen. Sammanfattningsvis kan konkluderas att östronuppgången föregick ökningen av prostaglandinmetaboliten och att den slutliga progesteronsänkningen inträffade samtidigt med att koncentrationen av prostaglandinmetaboliten ökade kraftigt. Den höga nivån av prostaglandinmetaboliten kvarstod i upp til fyra dygn efter förlossningen.
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References
- Adams W M, Wagner W C. The role of corticoids in parturition. Riol. Reprod. 1970;3:223–228. doi: 10.1093/biolreprod/3.2.223. [DOI] [PubMed] [Google Scholar]
- Anderson A B, Flint A P F, Turnbull A C. Mechanism of action of glucocorticoids in induction of ovine parturition: Effect of placental steroid metabolism. J. Endocr. 1975;66:01–70. doi: 10.1677/joe.0.0660061. [DOI] [PubMed] [Google Scholar]
- Bailey L F, McLennan M W, McLean D M, Hartford P R, Munroe G L. The use of dexamethasone trim ethyl acetate to advance parturition in dairy cows. Austr. vet. J. 1973;49:507–673. doi: 10.1111/j.1751-0813.1973.tb06735.x. [DOI] [PubMed] [Google Scholar]
- Comline R S, Hall L W, Lovelle R B, Nathanielz P W, Silver M. Parturition in the cow: Endocrine changes in animals with chronically implanted catheters in the foetal and maternal circulations. J. Endocr. 1974;63:451–1472. doi: 10.1677/joe.0.0630451. [DOI] [PubMed] [Google Scholar]
- Donaldson L E, Bassett J M, Thorburn G D. Peripheral plasma progesterone concentration of cows during puberty, oestrus cycle, pregnancy and lactation, and the effects of undernutrition or exogenous oxytocin on progesterone concentration. J. Endocr. 1970;48:599–614. doi: 10.1677/joe.0.0480599. [DOI] [PubMed] [Google Scholar]
- Edqvist L-E, Johansson E D B. Radioimmunoassay of oestrone and oestradiol in human and bovine peripheral plasma. Acta endocr. (Kbh.) 1972;71:716–730. doi: 10.1530/acta.0.0710716. [DOI] [PubMed] [Google Scholar]
- Edqvist L-E, Lindell J-O. Proc. 12th Nord, vet. Congr. 1974. The effect of prostaglandin on gonadal hormones and the course of pregnancy in the cow; p. 2715. [Google Scholar]
- Edqvist L-E, Ekman L, Gustafsson B, Åström G. Progesterone levels in the bovine peripheral plasma measured by the competitive protein binding technique. Zbl. Vet.-Med. 1970;A17:899–908. doi: 10.1111/j.1439-0442.1970.tb00783.x. [DOI] [PubMed] [Google Scholar]
- Edqvist L-E, Ekman L, Gustafsson B, Jacobsson S-O, Johansson E D B, Lindell J-O. Peripheral plasma levels of oestrone and progesterone in pregnant cows treated with dexamethasone. Acta endocr. (Kbh.) 1972;71:731–742. doi: 10.1530/acta.0.0710731. [DOI] [PubMed] [Google Scholar]
- Edqvist L-E, Ekman L, Gustafsson B, Johansson E D B. Peripheral plasma levels of oestrogens and progesterone during late bovine pregnancy. Acta endocr. (Kbh.) 1973;72:81–88. doi: 10.1530/acta.0.0720081. [DOI] [PubMed] [Google Scholar]
- Edqvist L-E, Kindahl H, Stabenfeldt G H. Proc. 8th Int. Congr. Anim. Rep rod. Comm. Abstracts, Krakow. 1976. On the role of prostaglandins in bovine parturition; p. 76. [Google Scholar]
- Evans L, Wagner W C. Bovine plasma oestrogens, progesterone and glucocorticoids during dexamethasone induced parturition. Acta endocr. (Kbh.) 1976;81:385–397. doi: 10.1530/acta.0.0810385. [DOI] [PubMed] [Google Scholar]
- Fairclough R J, Hunter J T, Welch R A S. Peripheral plasma progesterone and utero-ovarian prostaglandin F concentrations in the cow around parturition. Prostaglandins. 1975;9:901–914. doi: 10.1016/0090-6980(75)90078-7. [DOI] [PubMed] [Google Scholar]
- Flint A P F, Anderson A B, Steele P A, Turnbull A C. The mechanism by which foetal Cortisol controls the onset of parturition in the sheep. Bioehem. Soc. Trans. 1975;3:1189–1194. doi: 10.1042/bst0031189. [DOI] [Google Scholar]
- Granström E, Kindahl H. Radioimmunoassay for prostaglandin metabolites. Advances in Prostaglandin and Thromboxane Research. 1976;1:81–92. [PubMed] [Google Scholar]
- Hoffman B, Schams D, Gimenez T, Ender M L, Herrman C, Karg H. Changes of progesterone, total oestrogens, corticoids, prolactin and LH in bovine peripheral plasma around parturition with special reference to the effects of exogenous corticoids and a prolactin inhibitor, respectively. Acta endocr. (Kbh.) 1973;73:385–395. doi: 10.1530/acta.0.0730385. [DOI] [PubMed] [Google Scholar]
- Kindahl H, Edqvist L-E, Bane A, Granström E. Blood levels of progesterone and 15-keto-13,14-dihydro-prostaglandin F2a during the normal oestrous cycle and early pregnancy in heifers. Acta endocr. (Kbh.) 1976;82:134–149. doi: 10.1530/acta.0.0820134. [DOI] [PubMed] [Google Scholar]
- Lamond D R, Tomlinson R V, Drost M, Henricks D M, Jochie W. Studies of prostaglandin F2a in the cow. Prostaglandins. 1973;4:269–2184. doi: 10.1016/0090-6980(73)90045-2. [DOI] [PubMed] [Google Scholar]
- Lauderdale J W. Effects of PGF2a on pregnancy and estrous cycle of cattle. J. Anim. Sei. 1972;35:246. [Google Scholar]
- Louis T M, Stellflug J N, Tucker H A, Hafs H D. Plasma prolactin, growth hormone, luteinizing hormone and glucocorticoids after prostaglandin F2a in heifers (38295). Proc. Soc. exp. Biol. (N.Y.) 1974;147:128–133. doi: 10.3181/00379727-147-38295. [DOI] [PubMed] [Google Scholar]
- Pope G S, Gupta S K, Munro I B. Progesterone levels in the systemic plasma of pregnant, cycling and ovariectomized cows. J. Reprod. Fertil. 1969;20:369–381. doi: 10.1530/jrf.0.0200369. [DOI] [PubMed] [Google Scholar]
- Robertson H A. Sequential changes in plasma progesterone in the cow during the oestrous cycle, pregnancy, at parturition and post-partum. Canad. J. Anim. Sei. 1972;52:645–658. doi: 10.4141/cjas72-076. [DOI] [Google Scholar]
- Robertson H A. Changes in the concentration of unconjugated oestrone, oestradiol-17a and oestradiol-17ß in the maternal plasma of the pregnant cow in relation to the initiation of parturition and lactation. J. Reprod. Fertil. 1974;36:1–7. doi: 10.1530/jrf.0.0360001. [DOI] [PubMed] [Google Scholar]
- Smith V G, Edgerton L A, Hafs H D, Convey E M. Bovine serum oestrogens, progestins and glucocorticoids during late gestation. J. Anim. Sci. 1973;36:391–395. doi: 10.2527/jas1973.362391x. [DOI] [PubMed] [Google Scholar]
- Stabenfeldt G H, Osburn B I, Ewing L L. Peripheral plasma progesterone levels in the cow during pregnancy and parturition. Amer. J. Physiol. 1970;218:571–575. doi: 10.1152/ajplegacy.1970.218.2.571. [DOI] [PubMed] [Google Scholar]
- Steele P A, Flint A P, Turnbull A C. Activity of steroid C-17,20-lyase in the ovine placenta: Effect of exposure to fetal glucocorticoid. J. Endocr. 1976;69:239–246. doi: 10.1677/joe.0.0690239. [DOI] [PubMed] [Google Scholar]
- Wagner W C, Willham R L, Evans L E. Controlled parturition in cattle. J. Anim. Sci. 1974;38:485–489. doi: 10.2527/jas1974.383485x. [DOI] [PubMed] [Google Scholar]