BVD infection in adult dairy cows can cause reproductive wastage, weight loss and reduced milk yield. BVD also causes immune suppression, meaning cattle that have an active infection will be more likely to succumb to other diseases.
BVD infection can have major impacts during mating and pregnancy. It can cause infertility, embryo loss, abortions (slips), small slow-growing calves, deformed calves, and the birth of dead calves. The most damage is done when BVD infects pregnant cows. If a cow contracts BVD in the first 4 months of pregnancy, she may give birth to a Persistently Infected (PI) calf. PI animals are the main source of infection within the herd.
The main effects of BVD on your farm are:
- depressed herd reproductive performance
- more cases of general disease in cows and calves (mastitis, scouring, pneumonia etc)
- reduced milk production
- reduced growth rates in young stock
For more detailed information, consult with your vet at Tararua Veterinary Services.