What is bovine leukemia virus (BLV)?
Bovine leukemia virus (BLV) is a retrovirus that infects cattle and can lead to persistent infection. Many infected cattle show no obvious clinical signs, but BLV can have important herd-level implications.
What diseases are associated with BLV infection?
BLV infection has been associated with:
- Reduced immune function
- Decreased productivity in some herds
- Increased risk of other diseases in lactating cows
- Lymphosarcoma in a small percentage of infected cattle
How is BLV spread between cattle?
BLV is primarily transmitted through blood and infected lymphocytes. Common routes include:
- Reuse of needles or equipment
- Dehorning or surgical procedures without proper sanitation
- Insect vectors in some cases
How is BLV managed in dairy herds?
Control strategies focus on reducing transmission, including:
- Using clean needles and equipment for each animal
- Implementing good biosecurity practices during procedures
- Testing and culling or segregating infected animals in some herd programs
Acknowledgment
This FAQ was developed using content from WSU’s Veterinary Medicine Extension.
This information is not meant to be a substitute for veterinary care. Always follow the instructions provided by your veterinarian. Washington State University assumes no liability for injury to you or your animals incurred by following these descriptions or procedures.