Use of anthelmintics in cattle

THE parasites of cattle can be broadly categorised into endoparasites, which include helminths, protozoa and some larval stages of arthropods, and ectoparasites, which include ticks, mites, lice and flies. Anthelmintics are used primarily for the treatment of helminth (nematode, trematode and cestode) infections although some broad‐spectrum anthelmintics are also active against endoparasitic and ectoparasitic arthropod species. This article describes the range of activity of the major groups of anthelmintics available for use in cattle, and outlines how these drugs may be used in the strategic control of parasitic bronchitis and, in particular, parasitic gastroenteritis.