Goat Nematodes Overview

Nematodes of Goats

Species

• Goats are particularly susceptible to the Ostertagia, Haemonchus and Nematodirus species found in sheep

Epidemiology

• Goats mount a weaker immune response to gastrointestinal worms, c.f. sheep, although at the same time appear more tolerant of similar sized worm burdens
• More species contribute to the periparturient rise in worm egg output (Mainly Ostertagia in sheep; Ostertagia and Trichostrongylus in goats)
• Susceptible to Nematodirus battus (often accompanied by coccidia) and Haemonchus

Drug Susceptibility

• Anthelmintics are, in general, metabolised more quickly by goats therefore a higher dose is required
  • Levamisole needs 1.5x sheep dose rate
  • Benzimidazoles needs 1.3x sheep dose rate
• Anthelmintic resistance occurs much more quickly in goats than sheep. As many nematode species are common to both hosts, sheep should not be grazed on pastures previously used by goats

Approaches to Control

• Use sheep PGE control measures, especially pasture management. Use of silage aftermath to minimise anthelmintic usage and the risk of anthelmintic resistance developing
• Unfortunately, many goat rearers use anthelmintics excessively for example every 4-6 weeks; one treatment per grazing coupled with pasture management should be adequate
• Zero grazing recommended (minimise risk of resistance developing).

Test yourself with the Small Ruminant Nematodes Flashcards

Small Ruminant Nematodes Flashcards