Why test and remove BVD-PI animals from a cattle herd?
Persistently infected (PI) cattle are the major source of BVD infection and disease in cattle because they shed huge amount of BVD virus throughout their lives. The major economic loss associated with BVD in cow-calf operations is loss of income due to loss of calves either before birth (abortion), at birth (weak calves) or between birth and weaning (BVD-induced immunosuppression make calves more susceptible to common calf disease such as pneumonia and scours). Thus removal of BVD-PI animals from a cattle herd should result in: Improve reproductive performance in herd Improve pre-weaning performance in herd (weaning weights and calves weaned) Lower calf treatment costs and calf death loss Provide more marketable cattle (BVD free certified herd status) Can BVDV infection be eradicated from a herd with vaccination? No, BVD vaccination alone (with either modified-live or killed vaccines) cannot keep a cattle herd free of BVD-PI cattle nor completely control BVD infection according to the
