In utero Infection with Bovine Viral Diarrhoea Virus Associated with Neurological Symptoms

Several new-born pure Limousine calves were presented with neurologic signs that included ataxia and limb hypertonicity/spasticity. These animals showed appetite and were hand fed, soon after birth with colostrum from their dams. BVDV infection was suspected but blood from affected calves was negative to both antigens and BVDV antibodies. No animal in the herd had ever been vaccinated against BVDV. Necropsy and histopathological exam showed some evidence of BVDV infection that was later confirmed by immunohistochemistry. By relying on serology results, most probably affected by colostral antibodies, the correct diagnosis was delayed and adequate measures postponed. This case report shows the importance of knowing the limitations of each diagnostic test in order to correctly interpret results.