Singh Vidya, Mishra Niranjan, Kalaiyarasu S, Khetan R K, Hemadri D, Singh R K, Rajukumar K, Chamuah J, Suresh K P, Patil S S, Singh V P
ICAR-National Research Centre on Mithun, Medziphema, Dimapur, Nagaland, 797106, India.
ICAR-National Institute of High Security Animal Diseases, Anand Nagar, Bhopal, Madhya Pradesh, 462022, India.
Trop Anim Health Prod. 2017 Aug;49(6):1149-1156. doi: 10.1007/s11250-017-1310-z. Epub 2017 May 14.
Despite reports of BVDV infection in several domestic and wild ruminants, no information exists for mithun (Bos frontalis) species. Hence, this study was undertaken to determine prevalence of BVDV infection in mithuns, which contribute significantly to local economy in the North Eastern region of India. Blood and serum samples were collected between 2013 and 2016 from mithuns (n = 466) belonging to the states of Nagaland, Mizoram, and Arunachal Pradesh. Serum samples were tested for BVDV antibodies by a commercial ELISA and leukocytes were tested for BVDV by real-time RT-PCR. The overall true seroprevalence rate was 13.1% (95% confidence interval, CI: 6.9-17.8%) with higher prevalence in mithuns reared under semi-intensive system (27.5%) than in free-ranging mithuns (7.6%). Among the three states, seroprevalence (16.2%) was highest in Nagaland, while prevalence rates varied markedly among geographical locations. Age-wise data showed highest seroprevalence rate in >6-year-old animals (20.6%) than 2-6 years old (16.9%), 6 months-2 years old (8.5%), and <6-month-old animals (11.3%). The seroprevalence was higher in males (20.9%) than in females (12.1%). Among the four mithun strains, higher prevalence was evident in Manipur (30.3%) than Arunachal (21.3%), Nagaland (11.7%), and Mizoram strain (10.2%). However, no BVDV genomic RNA could be detected. The results provide first serological evidence of BVDV infection in mithun species and extend the knowledge on BVDV host range. The baseline data will help further investigations on epidemiology of BVD in mithun and its impact on mithun production.
尽管有关于牛病毒性腹泻病毒（BVDV）在几种家养和野生反刍动物中感染的报道，但对米什米牛（大额牛，Bos frontalis）物种尚无相关信息。因此，开展了本研究以确定米什米牛中BVDV感染的流行情况，米什米牛对印度东北地区的地方经济有重大贡献。在2013年至2016年期间，从那加兰邦、米佐拉姆邦和阿鲁纳恰尔邦的米什米牛（n = 466头）采集血液和血清样本。血清样本通过商业酶联免疫吸附测定（ELISA）检测BVDV抗体，白细胞通过实时逆转录聚合酶链反应（RT-PCR）检测BVDV。总体真实血清阳性率为13.1%（95%置信区间，CI：6.9 - 17.8%），半集约化饲养系统中的米什米牛（27.5%）的患病率高于自由放养的米什米牛（7.6%）。在这三个邦中，那加兰邦的血清阳性率（16.2%）最高，而不同地理位置的患病率差异显著。按年龄划分的数据显示，6岁以上动物的血清阳性率最高（20.6%），高于2 - 6岁（16.9%）、6个月至2岁（8.5%）以及6个月以下动物（11.3%）。雄性的血清阳性率（20.9%）高于雌性（12.1%）。在四种米什米牛品系中，曼尼普尔品系（30.3%）的患病率明显高于阿鲁纳恰尔品系（21.3%）、那加兰品系（11.7%）和米佐拉姆品系（10.2%）。然而，未检测到BVDV基因组RNA。这些结果提供了米什米牛物种中BVDV感染的首个血清学证据，并扩展了关于BVDV宿主范围的知识。这些基线数据将有助于进一步调查米什米牛中BVD的流行病学及其对米什米牛生产的影响。
