Serological evidence of an Australian bovine lentivirus.

Recombinant 26 kDa capsid (CA) proteins of bovine lentiviruses, bovine immunodeficiency virus (BIV) and Jembrana disease virus (JDV), were expressed in Escherichia coli and utilised as antigens for an enzyme-linked immunosorbent assay (ELISA) and a western immunoblot (WIB) procedure for the detection of antibody in dairy cattle in Western Australia. A total of 690 serum samples, 30 from each of 23 farms, were tested by ELISA with a JDV CA protein antigen, and antibody was detected in 3.8% (p<0.05) of the sera. Nine sera from each farm were also tested by WIB with JDV CA protein antigens and antibody was detected in 15.9% of these samples. All ELISA-positive results were also WIB-positive, and all sera antibody-positive by WIB with JDV CA protein antigens were also antibody-positive by the WIB using recombinant BIV CA antigens. This study showed that recombinant protein antigens can be used for serological tests to detect bovine lentivirus infection in Australia.