Claire McArthur - Moredun Research Institute

Grazing cattle are infected with a variety of gastrointestinal nematodes and methods of control rely heavily on the use of anthelmintics (also known as wormers or drenches). There have been a number of reports of anthelmintic resistance in cattle nematodes abroad, but little is known about the prevalence of sensitivity of these parasites to anthemintics in the UK. This project has taken steps to address this lack of information.

A questionnaire study has been conducted to ascertain parasite management practices, in conjunction with testing of an injectable ivermectin treatment in a cohort of farms. Two nematode isolates found to be resistant to ivermectin have been further characterised through an in vivo trial, have been investigated using an in vitro lab based test and are currently undergoing molecular analysis.