Sheep

Ovine pulmonary adenocarcinoma (OPA also known as Jaagsieke) is a contagious viral disease that leads to lung cancer of sheep. It is caused by Jaagsieke sheep retrovirus (JSRV). It is a significant production limiting disease in many countries of the world including the UK. All breeds are susceptible to OPA and no single breed has been shown to be more susceptible than another.