Monitoring of Bovine Viral Diarrhoea Virus (Bvdv) Infection in Polish Dairy Herds Using Bulk Tank Milk Samples

The aim of the study was to evaluate the status of bovine viral diarrhoea virus (BVDV) infection in selected dairy herds in Poland with the use of commercial enzyme linked immonosorbent assay for the detection of specific antibodies (BVDV-Ab ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) for the detection of viral RNA, using bulk tank milk (BTM) samples. Two hundred and thirty-one samples of BTM were collected from 99 dairy herds in Poland. The herds were divided into four different classes according to the Swedish system of classification. The results showed that 70.7% of herds were BVDV antibodypositive. High levels of antibodies in 52.85 % (37 herds in class 3) of all antibody positive herds indicated acute BVDV infection. Thirty five samples with the highest antibody levels were tested by RT-PCR and five of them were positive for viral RNA. Dairy herds in Poland have high levels of antibodies against BVDV in BTM. Since no vaccination was implemented in the herds tested, high seroprevalence of BVDV antibodies in cattle indicates the widespread of BVDV infection in Polish cattle