BVD (bovine viral diarrhoea) is one of the most common and costly diseases in New Zealand cattle. An estimated 35% of dairy herds and 65% of beef herds are currently or recently infected with BVD virus in New Zealand1, and an estimated 80% of New Zealand dairy and beef herds have been exposed to BVD virus at some point in time.2
A major issue for vets and farmers include the insidious, often hidden, nature of the disease, and the variety of clinical manifestations. Often what comes to the surface, in BVD outbreaks, is only the tip of the iceberg; the true impact of BVD is not realised in a lot of cases.
BVD has been shown to cause scouring and ill thrift in young cattle. In adult cattle, BVD is associated with reproductive losses, reduced milk production and elevated milk somatic cell count. The effects of BVD virus on fertility and on the unborn calf are profound, including low in calf rates, abortion, stillbirths, birth of “dummy calves” and the birth of persistently infected (PI) carriers of BVD virus.
BVD has been estimated to cost the average farm $54 per cow per year across New Zealand. That includes uninfected herds, in which the cost is much higher.
Unless you can break the cycle of creating new PI calves each year, BVD will become a chronic problem for your herd and you will continue to experience production losses1
Control of BVD is a process involving testing and culling of PI cattle, biosecurity measures to keep the virus out, and vaccination.
Advances in laboratory diagnosis mean that it is now simpler and more cost effective to diagnose and eradicate BVD from a herd, tests can be done on individual animals and on bulk milk samples.
Biosecurity measures include testing of all incoming stock onto the farm. An important group to test is breeding bulls – we recommend that all breeding bulls are tested for BVD virus before purchase. Once the herd is cleared of BVD the objective is to keep it clear.
Vaccination may be recommended by your vet as a simple and cost-effective measure for controlling BVD on your farm. Ultravac® BVD has been proven in New Zealand to be highly effective at preventing losses due to BVD, including protecting the foetus and preventing the birth of carrier (PI) cattle.
The first step in BVD control is to determine the BVD status of your farm, through appropriate testing. Then it’s a matter of working together with your vet to put in place a long-term management plan for control of the disease.
For further information on BVD control, talk to your vet today.
