Gwaredu Scab is pleased to announce its support for a major new research initiative led by the Moredun Research Institute (MRI), which has been awarded £1.2 million from the BBSRC to investigate resistance to the macrocylic lactone (ML) (injectable) treatments used for the control of sheep scab. There is now confirmed resistance to the MLs in sheep scab mites (Psoroptes ovis) in Wales and across the UK, with multiple resistant populations identified and documented in national surveillance and research studies. As part of this collaboration, Gwaredu Scab has been supplying P. ovis mite samples for functional and genetic analysis to assess their susceptibility to ML treatment and to identify the mechanism underlying the resistance.
During a recent visit to MRI, the Gwaredu Scab team saw first-hand the vital research underway to better understand and address ML resistance in P. ovis. This work has the potential to deliver significant long-term benefits for sheep health and welfare across both the Welsh and wider UK flock.
Sheep scab remains one of the most economically damaging endemic diseases affecting UK sheep farming. Current estimates place the national cost at £80–100 million annually, with each affected ewe costing farmers around £15 during an outbreak of the disease (Nixon EJ et all, 2020).
There are only two recognised treatment options for sheep scab, ML injectables and organophosphate (OP) plunge dipping.
By providing high-quality mite samples collected through the national programme, Gwaredu Scab is helping ensure researchers have access to the real-world material needed to analyse resistance patterns and develop practical, evidence-based solutions for farmers across Wales and the UK.
John Griffiths, Gwaredu Scab Programme Manager, said:
“We are proud to support this important research. Tackling treatment resistance is essential for safeguarding flock health and ensuring farmers have effective tools to manage sheep scab. Our contribution of mite samples reflects our commitment to collaborative, evidence-based disease control.”
Gwaredu Scab will continue to work closely with research partners, veterinary teams, and industry stakeholders to drive progress in the fight against sheep scab.
Gwaredu Scab is funded by the Welsh Government and delivered by Coleg Sir Gâr.
Nixon EJ, Wall R, Vineer HR, Stubbings L. The high cost of sheep scab. Vet Rec. 2020 Oct 17;187(8):325. doi: 10.1136/vr.m3888. PMID: 33060237