Āsīb/shināsī-i Darmāngāhī-i Dāmpizishkī (Nov 2015)
A comparative study for diagnosis of Bovine Leukemia Virus (BLV) infection in dairy cows by Polymerase Chain Reaction (PCR) and Enzyme Linked Immunosorbent assay (ELISA)
Abstract
Bovine Leukemia Virus (BLV) is a retrovirus that causes bovine enzootic leukemia (EBL). The routine method for the diagnosis of the infection is antibody screening tests. Agar gel immunodiffusion (AGID) and ELISA are widely used for detection of the antibody against BLV. Amplification and detection of the proviral DNA by PCR is a powerful method for direct detection of the infection. However there are some limitations for routine use of this method in laboratory diagnosis of the disease and it requires further investigations. The objective of this study was to compare the results of a PCR assay with a commercial ELISA in detection of the bovine leukemia provirus and antibodies to this agent, in blood samples of dairy cows. The ELISA was assumed as reference test and the relative sensitivity and specificity of the PCR assay was calculated by testing samples from 173 cows in suburb of Tabriz. Blood sample were taken and taken sera and DNA contents were harvested. Sensitivity and specificity of the PCR assay in caparison to commercial ELISA were 100% and 98.6% respectively. The frequency of the presence of the targeted part of gag gene in PCR was 13.3% and the frequency of the seropositive reaction by commercial ELISA was 12.1%. The results showed that it is possible to use PCR as a laboratory diagnostic method for identification of the disease.
