Total anthelmintic failure to control nematode parasites of small ruminants on government breeding farms in Sabah, East Malaysia

Government-owned small-ruminant breeding farms in Malaysia provide the source of sheep and goats to smallholder farmers in the country. In the eastern Malaysian state of Sabah, high-level stock losses have been recorded on these farms for several years, frequently accompanied by clinical signs indicating pathogenic levels of infections with the nematode parasite Haemonchus contortus. This suggests that their dependence on chemotherapy to control parasite infections had failed. Accordingly, tests for anthelmintic efficacy using the faecal egg count reduction test (FECRT) on the range of drugs used to control nematode parasites were carried out on the five government small-ruminant breeding farms in Sabah. These tests showed a total failure of the benzimidazole, imidothiazole, macrocyclic lactone and salicylanilide groups of anthelmintics to control H. contortus infections of sheep and goats on all farms. Drastic changes in animal management need to be made in an attempt to deal with this situation, for which suggestions are made.