PA12-15: Nematodes

Question 1

What are the trichostrongyles of ruminants?

Answer 1

Dictycaulus spp.
Ostertagia spp.
Teladorsagia spp.
Haemonchus spp.
Trichostrongylus spp.
Coopeiria spp.
Nematodirus spp.

Question 2

Which nematodes affect sheep & goat in the UK & which part of the animal do they affect?

Answer 2

Teladorsagia circumcinata & Haemonchus contortus affect abomasum.
Trichostrongylus vitrinus, Trichostrongylus colubriformis & Nematodirus battus affect the small intestine.

Question 3

Which nematodes affect cattle in the UK & what part of the animal do they affect?

Answer 3

Ostertagia ostertagi affects abomasum.
Cooperia spp. affects the small intestine.
Dictyocaulus viviparus affects lungs.

Question 4

Characteristics of Cooperia ancophora & Nematodirus hibernatus

Answer 4

Mildly pathogenic
Associated with poor weight gain & inappetence
Macrocyclic lactones are not very efficient against it
Lifecycle is similar to O. ostertagi

Question 5

How does nematode parasitism cause production loss?

Answer 5

Nematodes affect feed intake & utilisation by the host = weight loss.
Parasites have direct effects & can trigger an immune response that can be harmful to the host.

Question 6

In which types of sheep is parasitic gastroenteritis a problem?

Answer 6

Lambs in their first grazing season.
Naïve ewes
Rams
Sheep with poor immunity

Question 7

Average pre-patent period for nematodes

Answer 7

18 days