Year: 2020
Type: article
Abstract: Bovine leukosis (BL) is a chronic tumor disease of dairy cow caused by Bovine leukemia virus (BLV), which seriously harms the healthy development of dairy farming. In order to understand the prevalence of BLV in Holstein cows in Xinjiang, China, serological survey was conducted on 462 clinical serum samples of Holstein cows collected from 5 large-scale dairy farms during the period of 2015–2018. Molecular detection of BLV env gene was performed on 109 lymph node samples, and then phylogenetic relationship was also explored. The results showed that the overall sero-positive rate of BLV antibody in Holstein cow samples was 8.44% (39/462), while PCR positive rate was 5.50% (6/109), indicating that BLV infection was emerging in Holstein cows from large-scale dairy farms in Xinjiang. Compared with other regional epidemic strains in China and other countries in the world, the nucleotide and amino acid sequences of env gene of 6 BLV Xinjiang strains shared 98.9– 99.3 and 98.6–99.1% identities, respectively. Furthermore, a total of 55 mutation sites existed in the nucleotide sequence of env gene of 6 Xinjiang strains when compared with JPEH-2 strain from Japan, resulting in 18 mutations in amino acid residues. Phylogenetic analysis based on env gene showed that three genotypes, namely G1, G6, and G7, were substantively circulating in Holstein cows, showing significant genetic heterogeneity in epidemic strains of BLV in China.
Authors: Lixia Wang, Chengcheng Ning, Chunhui Ji, Yun Guo, Na Li, Jun Qiao, Qingling Meng, Xianzhu Xia, Xingxing Zhang, Yucheng Liu, Kuojun Cai, Zaichao Zhang, Jinsheng Zhang, Yelong Peng, Xuepeng Cai
Language: English
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: bronze
Award: G79450013
OpenAlex ID: W4417522930