Pestivirus (also known as BVDV – bovine viral diarrhoea virus) causes abortion, ill thrift in young animals, diarrhoea and respiratory disease.
Pestivirus is widespread throughout the Australian cattle population. About 70% of herds are actively infected with the virus. Infection of susceptible animals can cause a variety of diseases, some not apparent until well after the initial spread of the virus in a herd.
Clinical signs that would lead a producer to suspect pestivirus include:
- Early-term abortion or embryonic loss.
- Temporary infertility.
- Increased susceptibility to other diseases.
- Weak, stunted or deformed calves.
- Respiratory disease.
- Ill-thrift and wastage
There is an AgFact here, which lists various methods of control, including an annual vaccination (expensive) program.
Information on the required vaccination programme can be seen here