The first study of bovine immunodeficiency virus (BIV) and bovine viral diarrhea virus (BVDV) co- infection in industrial herds of cattle in two provinces of Iran

BIV is a well-known bovine immunosup-pressive cause, but its pathogenesis has not been well characterized. It seems that it is possible that cofactors such as co- infection with other bovine viral pathogens may play a role in enhancing the pathogenesis of BIV infection; BVDV also has immunosuppressive effects. OBJECTIVE: The aim of this study was determination of possible correlation between BIV and BVDV infections. METHODS: Blood samples were randomly collected from a total of 1800 cattle in dairy industrial farms in Isfahan and Chaharmahal va Bakhtiari provinces of Iran. First BIV or BVDV positive sera were screened by ELISA, and then samples were analyzed to detect BIV proviral DNA or BVDV RNA, using PCR. RESULTS: Out of 1800 blood samples, 19 (1.06%) samples were BVDV positive, while BIV positive samples were 10 (0.55%). Nine (0.5%) samples contained both BIV and BVDV genomes and were positive in ELISA, while one of the samples (0.05%) was only BIV positive. CONCLUSIONS: In this study, there was a statistically significant relationship between BIV status and BVDV infection using Chi square and Pearson's correlation coefficient test (p=0, r=0.65).