Presence of bovine leukemia virus genotypes 1 and 3 in Antioquia, Colombia

Abstract

Bovine leukemia virus (BLV) is an immunosuppressant retrovirus that primarily affects dairy livestock, its target cells are B lymphocytes in which it integrates its genome infecting cattle for life . It is important to identify the distribution of the BLV in the region and to reconstruct its evolutionary history through phylogenetic trees, for the province of Antioquia this is the first report of the BLV genotypes. The aim of this study was to identify the genotype of BLV circulating in dairy cattle of different regions of the province of Antioquia, Colombia . DNA was extracted from 8 Holstein cows. Nested PCR was performed to amplify a fragment of 444 pb of the env gene. The env viral gene codes for surface protein gp51, gene is highly conserved and it is used for phylogenetic analysis . Obtained amplicons were sequenced, manually aligned in MEGA V7 program, and compared to 53 viral env gene sequences registered in GenBank. Phylogenetic analysis was performed by Maximum Likelihood and Bayesian methods . Two circulating genotypes were found: the most common genotype was 1, found in seven samples; they grouped with sequences from EE. UU, Argentina and Japan; only one sample was classified as genotype 3 and was grouped with samples from EE . UU and Japan. At least two genotypes (1 and 3) of BLV are circulating in Antioquia; however, more cattle and herds should be evaluated to elucidate the diversity and distribution of BLV in Colombia.

Keywords

• Antioquia
• BLV
• Colombia
• Env gene
• Genotype
• Phylogenetic analysis