Pharmaceutical control of endoparasitic helminth infections in sheep.

Sheep are hosts to numerous genera and species of helminth parasites, which are an important cause of production-limiting diseases. Their proper treatment and control requires knowledge of the epidemiology of these parasites in the region where the farm is located, including knowledge of the important species and their pathogenic effects, the role of immunity and resilience of the sheep, survival of L(3) on pasture under different conditions, and farm management practices. Use of anthelmintics must be combined with this knowledge to reduce risk of development of anthelmintic resistance, particularly with the control of gastrointestinal nematode parasites. Copyright Â