Bovine Viral Diarrhoea Virus and Cattle Welfare

BVD is a major immunosuppressive disease of cattle that causes significant individual and herd-level welfare impacts through disease amplification and reproductive losses.

Key Facts

Cattle persistently infected (PI) with BVD virus are the primary source of infection — they shed virus continuously throughout their lives
PI animals are typically calves from immunotolerant pregnancies; they often appear clinically normal but have impaired immune function
BVD infection during early pregnancy causes embryonic death, abortions, stillbirths and birth of PI calves
BVD eradication programmes in Scotland, Ireland and Nordic countries have eliminated PI animals and dramatically reduced herd welfare impacts

Welfare Considerations

BVD creates compound welfare impacts: PI animals have lifelong immune compromise that makes them susceptible to secondary diseases; herd exposure causes reproductive failures and immunosuppression that amplifies the welfare cost of every other infection. The single most impactful welfare intervention in BVD-infected herds is identifying and removing PI animals — a relatively simple process using bulk milk or individual ear notch testing. National eradication programmes demonstrate that BVD can be eliminated from cattle populations entirely, transforming herd welfare.

What You Can Do

Test your cattle herd for PI animals using bulk milk ELISA or individual animal testing programmes
Remove identified PI animals from the herd immediately and do not allow contact with pregnant females
Vaccinate all cattle against BVD as part of a herd health plan while building toward PI-free status
Work with your vet to enrol in regional BVD eradication programmes where available