What is maedi visna?
Maedi visna (MV), along with caprine arthritis and encephalitis virus (CAEV), are part of the small ruminant lentivirus (SRLV) group of retroviruses, affecting affect sheep and goats. These viruses cause significant clinical disease in sheep (primarily wasting, lung pathology and mastitis) and goats (primarily arthritis) and are a major source of economic losses.
The clinical disease onset is slow and may be confused with many other pathogens, so the presence of virus in a flock is often missed or under-estimated. Current diagnostics also often miss early-stage infections. At present there are no vaccines or treatments, so control options rely on testing at a herd level, culling infected animals and biosecurity measures. Eradicating disease from a flock can be expensive and slow.
Our research and its impact
Our research on maedi visna focuses on several key areas, with the aim of better understanding and controlling the virus.
These include: the risk of the virus being transmitted sexually, the design of better PCR-based diagnostic tests for detecting a wider selection of current virus strains, the long-term disease impacts of infection on flocks, and breeding for genetic resistance to maedi visna.