Ice-berg Diseases in Sheep – Ovine Pulmonary Adenocarcinoma (OPA)

OPA – Ovine Pulmonary Adenocarcinoma (OPA) was first detected within the UK in 1888. Often referred to as “Jaagsiekte” it is caused by a retrovirus. This virus infects the lungs of sheep, causing tumours to develop and fluid to accumulate within the airways. OPA is a huge source of economic loss for farmers, with initial losses as high as 20-25% – reducing to 1-5% in endemic flocks. At present, there is no commercially available test or vaccine for OPA.