Prevalence and Anthelmintic Resistance in Gastrointestinal Nematodes of Sheep in Iran: A Systematic Review and How Overcome it

Abstract

Gastrointestinal nematodes (GIN) are an important cause of production losses in young grazing sheep, particularly<br>in intensive production systems. The prevention of GIN infections and parasitic gastroenteritis relies on broad<br>spectrum anthelmintic drugs. At present, the major classes of anthelmintics available for sheep belong to the<br>families of the benzimidazoles (albendazole, febendazole, and oxfendazole) ,imidazothiazoles (levamisole) and<br>macrocyclic lactones (avermectins).Anthelmintic resistance has been recognized in small ruminants worldwide, and<br>this phenomenon has increased to become a major worldwide problem to livestock industry.<br>A systematic review was conducted with the aim to measure the prevalence of sheep gastrointestinal nematodes<br>(GIN) in Iran and potential management factors associated with development of anthelmintic resistance.<br>Modern strategy for nematode control should not rely on sole use of anthelmintics.Targeted selective treatments<br>attract the interest of parasitologists towards maintaining parasites in refugia, seems to be a key point in controlling<br>and delaying the development of resistance. Therefore, it is needed to use novel non-chemical approaches that<br>decrease the need for treatment.