Anthelmintic Resistant Worms of Cattle - A Common Problem?

Using a new sensitive egg count test, FLOTAC, it has been shown that macrocyclic lactones (MLs) had reduced efficacy against gastrointestinal nematodes including Cooperia specie; and Ostertagia ostertagi on the majority of cattle farms investigated. Product failure was also found to levamisole injection against gastrointestinal nematodes, to albendazole in Dictyocaulus viviparus and MLs plus albendazole against Nematodirus helvetianus. In the light of these finding it is suggested that veterinary surgeons should play an important role in the planning of worm control in cattle herds and ensuring that products used are fully effective.