ICAR-National Institute of High Security Animal Diseases, Anand Nagar, Bhopal 462022, India.
Viruses. 2024 Aug 30;16(9):1390. doi: 10.3390/v16091390.
Border disease virus (BDV) causes significant economic losses in sheep farming worldwide. In India, BDV has not yet been studied in sheep migrating for summer pasturing. This study aimed to determine the extent of BDV infection in migratory sheep and provide genetic characteristics of BDV. Blood and serum samples from 90 lambs of a migratory sheep flock (600) in Central India were collected and subjected to molecular detection, phylogenetic analysis and virus neutralization test (VNT). We detected BDV in two lambs through real-time RT-PCR, while 64.4% (58/90) of in-contact lambs had BDV neutralizing antibodies. One apparently healthy lamb was found to be persistently infected with BDV. Phylogenetic analysis of 5'- and genes and the concatenated datasets typed the BDV isolate from PI sheep as BDV-3 genotype. However, it showed a closer relationship with BDV-3 strains from China than the previously reported Indian BDV-3 strains. This is the first report on the detection of BDV persistently infected migratory sheep in India. Additionally, we provided evidence of genetic variability among BDV-3 strains in India. The findings improve our understanding of epidemiology and genetic characteristics of BDV in India and highlight the potential risks associated with the traditional practice of sheep migration for summer pasturing.
边界病病毒（BDV）在全球范围内给绵羊养殖业造成了重大经济损失。在印度，对夏季放牧迁徙的绵羊中的 BDV 尚未进行研究。本研究旨在确定迁徙绵羊中 BDV 感染的程度，并提供 BDV 的遗传特征。从印度中部一个迁徙羊群（600 只）的 90 只羔羊中采集血液和血清样本，进行分子检测、系统进化分析和病毒中和试验（VNT）。我们通过实时 RT-PCR 在两只羔羊中检测到 BDV，而 64.4%（58/90）的接触羔羊具有 BDV 中和抗体。一只看似健康的羔羊被发现持续感染 BDV。对 5'-和 基因以及串联数据集的系统进化分析将来自 PI 绵羊的 BDV 分离株鉴定为 BDV-3 基因型。然而，它与中国先前报道的 BDV-3 株比印度已报道的 BDV-3 株与 BDV-3 株的关系更为密切。这是印度首次报道持续感染 BDV 的迁徙绵羊。此外，我们提供了印度 BDV-3 株之间遗传变异的证据。这些发现提高了我们对印度 BDV 的流行病学和遗传特征的认识，并强调了夏季放牧迁徙这一传统做法所带来的潜在风险。
