What is BVD clinical disease?
Most BVDV infection problems in cattle herds go unnoticed since 70-90% of BVD infections are subclinical (do not result in observable disease). When present, the most common disease caused by BVD virus infection in cattle herds is poor reproductive performance including, abortions, poor conception rates, stillbirths, and weak calves. In addition, BVD virus infection causes suppression of the bovine immune system resulting in increased susceptibility to other infectious diseases. In cow-calf herds the immunosuppressive effect of BVD is normally noticed as increased calf death loss (from scours and pneumonia) and poor weaning weight. In feedlot animals this is noticed primarily as increased death loss and incidence of respiratory disease (pneumonia). Lastly, BVD virus infection alone can cause diarrhea with oral ulcers and bleeding disorders. How is BVDV transmitted? The main source of BVDV in cattle herds is BVD-PI animals. Virus in BVD-PI animals is shed in all body secretions includin
