De ernst en verspreiding van resistentie bij maagdarmwormen tegen veelgebruikte anthelmintica in de Nederlandse schapenhouderij. Feceskweek en identificatie van larven na FECRT

Abstract

Unsupervised treatment of small ruminants with anthelmintics has led to anthelmintic resistance becoming a worldwide problem. Anthelmintic resistance against macrocyclic lactons has been proven in The Netherlands, but it is not clear how widespread the problem is. To determine this, a survey using Fecal Egg Count Reduction Tests (FECRT) and microscopic larval determination has started, with Haemonchus contortus being the main target of this research. Results: larvae developed from feces cultures before anthelmintic treatment are of various species. Larvae developed after anthelmintic treatment however, are mostly Haemonchus contortus. This confirms the suspicion that anthelmintic resistance in The Netherlands is not only apparent, but that it is mostly a problem of Haemonchus contortus species. A worrying development, as H. contortus can account for significant damage in the sheep business.