Bovine viral diarrhea virus antigen status in milk and blood serum: Implications for effective screening and risk factors analysis in dairy cows

Bovine viral diarrhea virus (BVDV) is a significant viral pathogen affecting cow populations worldwide. This study was conducted in the Bagha Bari area of Sirajganj District, Bangladesh, and investigated the prevalence of BVDV antigen in 54 dairy cattle exhibiting reproductive, milk production, and congenital abnormalities. Milk and blood samples were collected from dairy cows without a history of BVDV vaccination. The research work employs indirect enzyme-linked immunosorbent assay (ELISA) to detect viral antigen, and the results reveal a significant discrepancy in BVDV antigen positivity between milk (55.56%) and serum (92.60%) samples from the same animals. Interestingly, animals negative in one sample type tested positive in the other, indicating potential localized viral presence or shedding variations. ELISA titers differed between serum and milk samples, highlighting variations in viral dynamics within bodily fluids. Risk factor analysis shows an association between BVDV positivity and pregnancy. In conclusion, this study advocates a comprehensive testing approach involving both serum and milk samples for effective BVDV screening. Future studies should involve larger, geographically varied populations and incorporate molecular diagnostic tools, such as PCR, to enhance accuracy.