Mike Bardsley is a member of the steering commitee for this exciting project. The project was started by The members of the Norfolk and Suffolk Holstein Club because of their concern regarding the severe economic impact of this disease.
East Anglia has traditionally had a lower number of infected farms (c 75%) than the national average (c 95%0).
Our aim is to eradicate BVD virus from our region, it does not matter if you currently vaccinate, you can still join. Previous BVD-free schemes have not been able to allow vaccination. However our main priority is to eliminate the virus from the region and if farmers have to vaccinate for biosecurity reasons this is quite OK.
Our first target is to reach 100 farms in the region which are free of BVD virus.
BVD virus is carried by persistently infected cattle (PI’s) and these animals eventually die from Mucosal Disease or secondary infections. BVD cannot survive without these PI’s as a source of infection, therefore by tracking these animals down and removing them from the herd them we will remove the threat of this diseae.
The testing is done by SAC and is subsidised by funding from EBLEX and Holstein UK. For dairy farmers an initial screen involves a bulk milk test plus 5 blood samples from each separately managed group of 9 – 18 month old heifers.
New tests have allowed us to detect virus in bulk milk samples from up to 300 cows. In addition we are now able to screen calves for infection at 1 month of age rather than waiting until they are 9 months or older.
We are very fortunate to have Professor Joe Brownlie from the Royal Vet College, London to design and oversee this project. Prof Brownlie was instrumental in making the discoveries that have led to our understanding the mechanism of infection
Many farmers don’t realise their herds are infected with BVD, Conversely many farmers do not know if their herd is naive. Those farmers that are not infected may be at significant risk of becoming so with potentially disastrous consequences.
The main risk factors for aquiring BVD infection are:
- Hiring of bulls.
- Purchasing Cattle.
- Contact with sheep.
- Contact with neighboring stock -escaped animals or over the fence.