Ovine pulmonary adenocarcinoma virus, commonly known as OPA virus, is a highly contagious retrovirus that primarily affects sheep and goats. It belongs to the family Retroviridae and the genus Betaretrovirus. OPA virus is responsible for causing a severe and chronic respiratory disease known as ovine pulmonary adenocarcinoma (OPA).
OPA virus is transmitted through respiratory secretions, mainly by direct contact between infected and susceptible animals. The virus primarily targets the lungs, where it infects and transforms the epithelial cells lining the airways and alveoli. This transformation leads to the formation of tumors or adenomas, which eventually progress into adenocarcinomas.
Affected animals may initially show mild clinical signs, such as a cough, nasal discharge, and exercise intolerance. As the disease progresses, more severe symptoms may develop, including weight loss, difficulty breathing, and pneumonia. In advanced stages, OPA can cause metastasis to other organs, such as the lymph nodes and liver.
OPA virus poses significant economic and animal welfare concerns, as it can severely impact sheep and goat populations, particularly in intensive farming systems. Control measures for OPA mainly focus on biosecurity practices, such as quarantining and culling infected animals, as well as vaccinations where available.
In conclusion, Ovine pulmonary adenocarcinoma virus is a retrovirus that causes ovine pulmonary adenocarcinoma, a chronic respiratory disease, primarily affecting sheep and goats. It is highly contagious and can lead to tumor formation in the lungs, leading to significant economic losses in affected animal populations.
