Cai Qijian, Lei Mengtong, Li Chunhua, Cai Jinzhong, Ma Doudou, Zhang Houshuang
Key Laboratory of Animal Parasitology, Ministry of Agriculture and Rural Affairs, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China.
Qinghai Academy of Animal Science and Veterinary Sciences, Xining 810016, China.
Animals (Basel). 2023 Oct 26;13(21):3330. doi: 10.3390/ani13213330.
The objective of this investigation was to understand the epidemiology of fascioliasis in yaks in the alpine pastoral areas of the Qinghai-Tibet Plateau, China. The prevalence of infection was estimated by examining eggs in the feces of yaks and by autopsy after the slaughter. Yaks were sampled from a total of 16 representative counties in Qinghai province, and risk factors were assessed based on regional and age characteristics. Fecal samples were obtained from 1542 yaks aged 0-1 (<1 year old), 1-2 (≥1 year old and <3 years old), and over 3 years (≥3 years old). In addition, 242 yaks over 3 years old who had not undergone fecal examinations were randomly selected for autopsy. A total of 267 fecal samples were positive for spp. eggs. The average infection rate was 17.32% (0-60.61%), and the average infection intensity was 51.9 eggs per gram (epg) of feces, with intensities ranging from 18 to 112 epg. In Maduo, Dari, Zhiduo, Chengduo, and Datong counties, the spp. eggs infection rate was zero. spp. adult flukes were detected in 66 out of 242 yaks at autopsy, with a total infection rate of 27.27% and an average infection intensity of 21.2 (adult worms), with intensities ranging from 3 to 46 worms. Logistic regression model analysis showed that age was a significant risk factor for yak infection with spp. In addition, the risk varied between regions: Haiyan, Gangcha, Duran, and Wulan were all high-risk areas for yak infection with spp. The spatial distribution of the spp. infection rate in each region showed a very weak negative correlation (Moran's I = -0.062), Duran formed a spatial distribution of high-low clusters with surrounding areas, and Datong formed a low-high clustering distribution characteristic with the surrounding areas. This investigation revealed that the infection rate of spp. in yaks was higher on the Qinghai-Tibet Plateau. Increasing age was a risk factor for infection with spp.; different regions also have a different risk of spp. infection. Only two regions showed clustering characteristics in the spatial distribution of infection rates. These findings extend the epidemiological information on spp. infection in yaks and provide baseline data for the execution of control measures against spp. infection.
本调查的目的是了解中国青藏高原高寒牧区牦牛的片形吸虫病流行病学情况。通过检查牦牛粪便中的虫卵以及屠宰后的尸检来估计感染率。从青海省16个具有代表性的县采集牦牛样本，并根据地区和年龄特征评估风险因素。从1542头年龄为0 - 1岁（<1岁）、1 - 2岁（≥1岁且<3岁）和3岁以上（≥3岁）的牦牛获取粪便样本。此外，随机选择242头3岁以上未进行粪便检查的牦牛进行尸检。共有267份粪便样本的 spp. 虫卵呈阳性。平均感染率为17.32%（0 - 60.61%），平均感染强度为每克粪便51.9个虫卵（epg），强度范围为18至112 epg。在玛多、达日、治多、称多和大通县， spp. 虫卵感染率为零。在242头尸检牦牛中，有66头检测到 spp. 成虫，总感染率为27.27%，平均感染强度为21.2（成虫），强度范围为3至46条虫。逻辑回归模型分析表明，年龄是牦牛感染 spp. 的一个重要风险因素。此外，不同地区的风险有所不同：海晏、刚察、都兰和乌兰都是牦牛感染 spp. 的高风险地区。各地区 spp. 感染率的空间分布呈现出非常弱的负相关（莫兰指数I = -0.062），都兰与周边地区形成高低聚集的空间分布，大通与周边地区形成低高聚集分布特征。本调查表明，青藏高原牦牛的 spp. 感染率较高。年龄增长是感染 spp. 的一个风险因素；不同地区的 spp. 感染风险也不同。只有两个地区在感染率的空间分布上呈现聚集特征。这些发现扩展了牦牛 spp. 感染的流行病学信息，并为实施针对 spp. 感染的控制措施提供了基线数据。
