Efficacy of anthelmintics against cattle nematodes.

The efficacies of fenbendazole and thiabendazole against artifically acquired cattle nematodes and the efficacies of fenbendazole, prabendazole and levamisole against naturally acquired cattle nematodes were studied in western Victoria. Fenbendazole significantly (P less than 0.05) reduced numbers of late and early fourth stage larvae (greater than 96%), artificially acquired Cooperla spp (100%) and naturally acquired adult Ostertagia ostertagi (98%) and Trichostrongylus axei (90%). Thiabendazole significantly reduced numbers of artificially acquired late fourth stage larvae (83%) and parbendazole significantly reduced numbers of adult O. ostertagi (72%) in one group of cattle. Fenbendazole was the most effective anthelmintic.