Investigation on the incidence of bovine viral diarrhoea virus in calves born with encephalopathy in Turkey.

The role of Bovine Viral Diarrhoea (BVD) virus in calves born with congenital brain abnormalities in western, southern and southeastern parts of Anatolia was investigated. 639 blood serum samples collected from cows which had aborted or given birth to calves with congenital abnormalities, from their offspring and from clinically healthy animals out of the above mentioned regions were tested for the presence of BVD antibodies. Additionally BVD virus isolation was performed with material obtained from cows which had aborted or given birth to calves with congenital abnormalities and from their offspring. Out of 639 blood sera 203 (31.7%) were found serologically positive, and from samples of 30 animals tested by direct immunofluorescence technique 13 (7 cows and 6 calves) BVD virus carriers could be demonstrated. The findings reveal that BVD virus infections might be a cause of malformations found in these calves born with congenital abnormalities of the central nervous system.