CONTAMINATION OF FOETAL BOVINE SERUM WITH BOVINE VIRAL DIARRHOEA VIRUS (BVDV)

Twelve batches of commercially available foetal bovine sera were tested for the presence of bovine viral diarrhoea virus (BVDV) and BDVD antibodies. The antibodies were found in three batches coming from two suppliers. Fragments of BVDV genome were present in five of these batches when tested by RT-PCR. All of them were type 1 BVDV according to a direct sequencing of PCR products. However, the further analysis of the samples by virus isolation showed that all RT-PCR positive batches contained non-infectious BVDV. Hence, inactivation methods used during the production process proved to be efficient making the tested sera safe for the use in cell Culture and for vaccine production. Results of RT-PCR detection of viral genome must be treated with caution since not in every case positive results indicate that the virus is live and infectious. Genetic typing based on sequence analysis of PCR products confirmed wide geographic spread of donor cattle.