What is Bovine Viral Diarrhoea Virus (BVDV) or "Pesti"?
In Australia, BVDV has recently been identified as the second most economically significant disease of cattle after tick infection, (with an estimated impact of AUD 114 million per annum and the most important pathogen in southern Australian tick-free zones
The cost of BVDV can vary from $20 to $90 per head on affected properties. Losses are primarily due to lost productivity as a result of immune suppression and reproductive losses (Reichel et al., 2018).
Approximately 90% of Australian beef production systems have evidence of recent exposure to the virus and over half are likely to be actively infected with BVDV (Reichel et al., 2018).
Bovine viral diarrhoea Virus is the most prevalent infectious disease of cattle worldwide.
BVDV is a silent killer
Whilst BVDV can cause devastating effects on farms that have not had BVDV exposure, due to the widespread nature of BVDV, most producers will see no overt clinical signs of BVDV.
3 Types of Infection
1. Acute (transient)
Exposure to the virus normally results in a transient infection (the cow will get better)
2. Foetal Infection:
If a cow is exposed whilst pregnant, abortions, still births and reduced fertility are likely (Reichel et al., 2018).
3. Persistent Infection (PI):
When foetal infections occur before the development of immunocompetence, persistently infected (PI) cattle are born. PI animals shed high levels of virus (Reichel et al., 2018).
The Impact of BVDV infection during pregnancy
Approximate timing of infection
0 - 40 days
Early embryo loss
40 - 120 days
Persistently infected calf
100 -140 days
Congenitally malformed calf
120 - 280 days
Normal or small, weak calf
How does BVDV Spread?
Persistently infected (PI) animals shed large quantities of virus and therefore are the single most important source of infection on farm BVDV is almost exclusively spread by direct contact with PI cattle (Development, 2019).
All BVDV control efforts need to focus on the identification and elimination of PI animals.