Moredun Research Institute awarded grant to tackle resistance to sheep scab treatments
The Moredun Research Institute, in collaboration with leading partners, has been awarded a £1.2M grant to explore the mechanism of resistance to the macrocyclic lactone (ML) injectables in the sheep scab mite, Psoroptes ovis, and how this resistance has spread across the UK.
The three-year award involves project partners from the University of Glasgow, Scotland’s Rural College (SRUC), and the Sustainable Control of Parasites in Sheep (SCOPS) Industry Group.
Sheep scab, a highly contagious disease caused by the ectoparasitic mite P. ovis., represents a significant welfare and economic concern for UK livestock production, costing the industry between £80-200 million annually. Current control strategies rely on organophosphate (OP) sheep dips and ML injectables (ivermectin, doramectin, and moxidectin). However, overreliance on ML injectables for controlling gastrointestinal nematodes (GIN) and sheep scab has led to the emergence of ML-resistant parasites, posing a significant threat to sheep health and welfare. While OP dipping is an effective alternative, it is associated with more complex safety requirements for both operators and the environment and if overused scab mites could also develop resistance to OP.