Development of a polymerase chain reaction and its comparison with agar gel immunodiffusion test in the detection of bovine leukemia virus infection

Polymerase chain reaction (PCR) was used for bovine leukemia virus (BLV) detection in the peripheral leukocytes of the infected bovines. The primers used were designed to amplify a part of env gene of BLV. PCR products were analyzed by agarose gel electrophoresis stained by ethidium bromide. The analytical specificity of PCR was confirmed by enzymatic restriction analysis of the PCR product with Bam HI and also by nucleotide sequence analysis of three PCR samples. Sixty five animals were tested for anti-BLV antibody, by agar gel-immunodiffusion test (AGID) and for direct BLV detection by PCR. There was a 73.80% concordance rate between the two tests. Four animals positive in AGID were PCR negative, while 13 AGID negative animals were found PCR positive. PCR got a 0.87 diagnosis sensitivity and 0.62 specificity. The developed PCR may be complementary tool in the diagnosis of BLV infection, but should have it diagnosis sensitivity improved. Key-words Immunodiffusion. Bovine leukemia virus. Gene. Polymerase chain reaction.