Development of methods to study Haemonchus contortus and anthelmintic resistance to monepantel

Abstract

Major economic losses in sheep production are caused by gastrointestinal nematode parasites, mainly by Haemonchus contortus, e by resistance to the anthelmintics used in their control. Therefore, this study was designed to increase knowledge in monepantel anthelmintic resistance and for H. contortus control in sheep. Firstly, polymorphisms detected in a genome-wide study will be validated as molecular markers of H. contortus resistance to monepantel, to be used for early diagnosis and monitoring of resistance in parasite populations. Furthermore, an in vitro technique for culture of H. contortus from eggs and infective larvae to fertile adults producing viable descendants will be developed, aiming to replace methods that involve sheep hosts for crossing parasites resulting in the introgression of resistance genes, and also to make available the adult stage of this nematode for in vitro assays of new compounds or for alternative methods for parasite control, as gene edition and vaccine development. Thus, considering the worldwide problem of anthelmintic resistance, the results obtained in this project will contribute to extend the efficacy of available commercial anthelmintics, to detect molecular markers of resistance in H. contortus, and to develop alternative measures for worm control in sheep flocks. (AU)