Leading farmers, vets and livestock health experts say the time has come to develop a scheme to control the sheep industry curse of ovine pulmonary adenocarcinoma (OPA).
A workshop at the Moredun Research Institute concluded that doing nothing to control the insidious disease in Scotland is no longer an option, and in the absence of any vaccine, treatment or blood test, ultrasound scanning could be used as a diagnostic tool to identify sheep with pre-clinical OPA.
The experts also concluded that more education is required to raise awareness of the disease and its transmission.
OPA is an infectious lung cancer specific to sheep which is caused by a virus, and typical signs in an affected animal are difficulty in breathing, often with marked weight loss, although clinical signs may not show for several years.
It is introduced through the purchase of apparently healthy animals and the virus can spread among the flock.
One scheme which was discussed would allow individual flocks to achieve monitored OPA status to sell sheep certified as low risk for OPA transmission. Ultrasound screening, post mortem examination of culled sheep and feedback from abattoirs would all be involved in the programme. A national eradication scheme based on scanning did not attract support.
Scotland’s chief vet, Sheila Voas, said: “We need to work together to tackle OPA as we now have the tools to make a difference. Prevention and control of diseases such as OPA will significantly improve the health and welfare of our sheep flocks and will improve production efficiency and increase profitability for farm businesses.”
Moredun scientist Dr Chris Cousens added it was imperative that research continued to develop and apply better diagnostic tests and tools to control the disease.
