Table 1.
Morphological characteristics, pre-patent periods and locations in the host of key genera and species of gastrointestinal nematodes infecting sheep in Australia[6,7,15,92]
| Family | Species |
Morphometrics/morphology |
Prepatent period |
Location in the host | |
|---|---|---|---|---|---|
| Length (mm) | Features | (days) | |||
| Trichostrongylidae |
Haemonchus contortus |
♂ 10-20 |
Red pseudocoelomic fluid and white coiled ovaries giving the appearance of a barber's pole. |
18-21 |
Abomasum |
| ♀ 18-30 | |||||
| Presence of vulvar flap depends on strain. | |||||
|
Teladorsagia circumcincta |
♂ 7-8 |
Small head and buccal cavity. |
15-21 |
Abomasum |
|
| ♀ 10-12 |
In females, a vulvar flap can be present. |
||||
|
Trichostrongylus axei |
♂ 2-6 |
Dissimilar spicules of unequal length. |
15-23 |
Abomasum |
|
| ♀ 3-8 |
or stomach |
||||
|
T. colubriformis |
♂ 4-8 |
Equal length spicules with triangular tip. |
15-23 |
Anterior small intestine |
|
| ♀ 5-9 |
|
||||
|
T. vitrinus |
♂ 4-7 |
Equal length spicules with sharp tips. |
15-23 |
Anterior small intestine |
|
| ♀ 5-8 |
|
||||
|
T. rugatus |
♂ 4-7 |
Dissimilar spicules with foot-like appearance. |
15-23 |
Small intestine |
|
| ♀ 6-7 |
|
||||
|
Cooperia curticei |
♂ 4-5 |
Transverse striation of cuticle in all species. |
14-15 |
Small intestine |
|
| ♀ 5-6 |
Watch-spring-like body posture and presence |
||||
| a small cephalic vesicle are characteristic. | |||||
| Molineidae |
Nematodirus spathiger |
♂ 10-19 |
Small but distinct cephalic vesicle. |
18 |
Small intestine |
| ♀ 15-29 |
Very long spicules ending in a |
||||
| spoon-shaped terminal piece. | |||||
|
N. filicollis |
♂ 10-15 |
Small but distinct cephalic vesicle. |
18 |
Small intestine |
|
| ♀ 15-20 |
Long and slender spicules with a |
||||
| narrow, lanceolate membrane. | |||||
| Ancylostomatidae |
Bunostomum trigonocephalum |
♂ 12-17 |
Anterior end is bend dorsally, |
40-70 |
Small intestine |
| ♀ 19-26 |
Buccal capsule with two cutting plates. |
||||
| Chabertiidae |
Oesophagostomum columbianum |
♂ 12-16 |
Have two leaf crowns and a shallow |
40-45 |
Large Intestine |
| ♀ 14-18 |
buccal capsule. Position of cervical papillae |
||||
| used for species differentiation. | |||||
|
O. venulosum |
♂ 11-16 |
Cervical papillae are situated |
40-45 |
Large intestine |
|
| ♀ 13-24 |
posterior to the oesophagus. |
||||
|
Chabertia ovina |
♂ 13-14 |
Mouth is directed antero-ventrally. |
42-50 |
Large intestine |
|
| ♀ 17-20 |
Buccal capsule is subglobular |
||||
| without teeth. | |||||