| Nematode Larvae |
Head |
Tail of Sheath |
Other |
Overall Length |
| Strongyloides |
|
no sheath |
oesophagus > a third of larval length; tail often truncated |
|
| sheep |
|
|
|
574-710 µm |
| cattle |
|
|
|
524-678µm |
| Trichostrongylus |
tapered |
short |
tuberosities sometimes present |
|
| sheep |
|
21-40µm |
|
622-796µm |
| cattle |
|
25-39µm |
|
619-762µm |
| Haemonchus |
round |
medium |
tail often appears to be kinked or offset |
|
| sheep |
|
65-78µm |
|
650-751µm |
| cattle |
|
87-119µm |
|
749-866µm |
| Teladorsagia |
square |
short/medium |
|
|
| sheep |
|
30-60µm |
shorter tail sheath in sheep |
797-910µm |
| cattle |
|
55-75µm |
|
784-928µm |
| Cooperia |
square |
medium |
two refractile bodies near mouth opening; can look like a horizontal bar |
|
| sheep |
|
35-82µm |
|
711-924µm |
| cattle |
|
47-111µm |
|
726-857µm |
| Oesophagostomum |
round |
long |
16-24 triangular intestinal cells |
|
| sheep |
|
125-160µm |
|
771-923µm |
| cattle |
|
134-182µm |
|
726-857µm |
| Chabertia |
round |
long |
24-32 rectangular intestinal cells |
|
| sheep |
|
110-150µm |
|
710-789µm |
| cattle |
|
|
|
|
| Bunostomum |
round |
long |
short stout larvae; 16 intestinal cells |
|
| sheep |
|
85-115µm |
|
514-678µm |
| cattle |
|
59-83µm |
|
500-583µm |
| Nematodirus |
round |
extra long |
often not encountered as require >20 days in culture; tail notched |
|
| sheep |
|
250-290µm |
|
922-1118µm |
| cattle |
|
207-266µm |
|
1095-1142µm |