Bovine Viral Diarrhea (BVD)

Bovine viral diarrhea virus (BVDV) is an economically important pathogen of cattle and it occurs worldwide. The biology of this virus is complex because it is associated with many diverse clinical manifestations, ranging from mild acute infections to fatal mucosal disease. BVDV can infect cattle at all ages including the fetus (1-3). Serological evidence shows that BVDV is a common infectious agent in beef cattle herds and feedlots (4). Major economic losses lately in Saskatchewan have been mucosal disease and calf mortality of persistently infected animals (5, 6) . Furthermore, BVDV probably plays together with other infectious agents a role in calf pneumonia (‘shipping fever’; 1, 2, 7). Thus it is important to control and prevent BVDV infections by vaccination and by identification and elimination of persistently infected cattle, which are the major source of infection.