摘要: A number of anthelmintics are available for the control gastrointestinal nematodes in cattle. In North America, O. ostertagi, Cooperia spp., lung worm, and F. hepatica probably cause greatest losses production. The older often deficient their action against some these parasites. Recently, Paratect morantel tartrate slow-release bolus has provided a mechanism prevention infections with to extent, this been shown produce considerable economic benefits. Fenbendazole removes arrested ostertagi larvae; thus, its availability is an important step type-2 ostertagiasis. It also very broad spectrum activity that includes most other tapeworms safe anthelmintic. Ivermectin highly effective almost all cattle great value arthropod ectoparasites. addition, it levamisole only anti-nematode drugs can be administered by injection. Clorsulon new, anthelmintic provides good liver fluke and, fills gap helminths America. efficient use association management based on knowledge parasite epidemiology ensure do not rapidly become re-infected. way, benefits from far greater than costs control.