Seroprevalence to bovine immunodeficiency virus and lack of association with leukocyte counts in Italian dairy cattle

We report herein on the first serological detection of antibodies to bovine immunodeficiency virus (BIV) in Italy. According to criteria of a stratifi ed-random sampling of dairy cattle reared in the Parma area (a province in the Po Valley, Northern Italy), sera from 3166 cows belonging to 272 herds were collected. In addition, sera of 138 bulls from eight artificial-insemi nation (AI) centres were sampled. Seventy-eight cows (2.5%) from 16 herds ( 5.8%) and seven bulls (5.1%) from two AI centres were positive for BIV-R29 antibodies in the IFA-test. IFA-positive, sera assayed by Western blot had reaction to different viral proteins: 81 out of 85 sera showed antibody to p26 (considered the BIV major internal core protein); four sera reacted to other viral proteins but not to p26. Peripheral blood leukocytes of 60 sero positive and 60 seronegative animals, belonging to eight BIV-infected herds , were enumerated to assess any effect of BIV infection on white-blood cell s. No significant differences were detected between the two groups. These d ata indicate that BIV infection is present in Italian dairy cattle - but th e role of BIV in inducing disease remains unclear. (C) 1998 Elsevier Scienc e B.V. All rights reserved.