Zeng Jiangyong, Duoji Ciren, Yuan Zhenjie, Yuzhen Silang, Fan Weixing, Tian Lili, Cai Chang, Robertson Ian
College of Veterinary Medicine, School of Veterinary and Life Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia, 6150, Australia.
Department of Veterinary, Tibet Livestock Research Institute, Tibet Academy of Agriculture and Animal Science, Lhasa City, Tibet, 850009, China.
Trop Anim Health Prod. 2017 Oct;49(7):1339-1344. doi: 10.1007/s11250-017-1331-7. Epub 2017 Jun 17.
A cross-sectional study was conducted in three counties (Damxung, Maizhokunggar and Yadong) in Tibet in April and May 2015. A total of 1,523 yaks owned by 181 herders were randomly selected and blood sampled. Sera were tested using the rose bengal test (RBT) and a competitive immune-enzymatic assay (C-ELISA) and the test results interpreted in parallel. The individual yak prevalence was 2.8% (95% CI 2.0-3.7) with a herd prevalence of 18.2% (95% CI 12.9-24.6). At the individual level, two predictor variables, age and production system, were significantly associated with seropositivity by a binary logistic regression analysis. The odds of Brucella infection were significantly higher in older Yaks (3-5 years old, OR = 4.51; 95% CI 1.53-19.29; ≥6 years old, OR = 3.89; 95% CI 1.23-17.21) compared to those of younger yaks (≤2 years old). The odds of seropositivity for yaks managed under an agro-pastoral production system were 2.9 (95% CI 1.48-5.86) times higher compared to those managed under a pastoral production system. At the herd level, an association between the infection with Brucella and a history of abortions in the herd was observed (OR = 4.98, 95% CI 1.48-16.62). Surprisingly, vaccination was not associated with a lower level of infection (p = 0.49 and p = 0.99 for individual and herd level data, respectively). The results of the survey indicate that bovine brucellosis is endemic among the yak population in the plateau region of China, and the risk factors identified in the study should be considered in the epidemiology of the disease and when developing control programs for the disease.
2015年4月和5月，在西藏的三个县（当雄、墨竹工卡和亚东）开展了一项横断面研究。随机选取了181名牧民拥有的1523头牦牛，并采集血样。血清采用玫瑰红试验（RBT）和竞争性免疫酶测定法（C-ELISA）进行检测，并对检测结果进行平行解读。牦牛个体患病率为2.8%（95%可信区间2.0 - 3.7），群体患病率为18.2%（95%可信区间12.9 - 24.6）。在个体水平上，通过二元逻辑回归分析，年龄和生产系统这两个预测变量与血清阳性显著相关。与年轻牦牛（≤2岁）相比，年龄较大的牦牛（3 - 5岁，比值比 = 4.51；95%可信区间1.53 - 19.29；≥6岁，比值比 = 3.89；95%可信区间1.23 - 17.21）感染布鲁氏菌的几率显著更高。与采用牧业生产系统管理的牦牛相比，采用农牧结合生产系统管理的牦牛血清阳性几率高2.9倍（95%可信区间1.48 - 5.86）。在群体水平上，观察到布鲁氏菌感染与群体中流产史之间存在关联（比值比 = 4.98，95%可信区间1.48 - 16.62）。令人惊讶的是，疫苗接种与较低的感染水平无关（个体和群体水平数据的p值分别为0.49和0.99）。调查结果表明，牛布鲁氏菌病在中国高原地区的牦牛群体中呈地方性流行，在该疾病的流行病学研究以及制定疾病控制计划时，应考虑本研究中确定的危险因素。
