College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang 453003, China; Postdoctoral Research Base, College of Veterinary Medicine, Henan Agricultural University, Zhengzhou 450046, China.
College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang 453003, China.
Poult Sci. 2022 Dec;101(12):102182. doi: 10.1016/j.psj.2022.102182. Epub 2022 Sep 13.
Blastocystis is a gastrointestinal protozoan parasite commonly reported in humans and animals globally, including poultry, and it can cause zoonotic transmission of blastocystosis. However, comprehensive information is not available on the prevalence, subtype distribution and zoonotic potential of Blastocystis in chickens in China. In this study, a total of 1,000 individual fecal samples of free-range broiler chickens of 4 breeds were collected from 43 farms in 5 cities of Guangdong Province and investigated for the occurrence of Blastocystis infection. Blastocystis was determined by nested PCR analysis of the small subunit ribosomal RNA (SSU rRNA) gene. The overall prevalence was 20.1% (201/1,000) in chicken samples and 69.8% (30/43) in screened farms, and considerable variation in prevalence between farms was evident, with a range of 0 to 76.9%. Population differences of Blastocystis in broilers among sites, breeds, and ages were assessed. The highest infection rates were observed in Yangjiang city (35.8%, 38/106), Sanhuang chickens (29.7%, 104/350), and the >80-day-old chicken group (30.5%, 40/131). DNA sequencing and phylogeny analyses identified 2 zoonotic subtypes, ST6 and ST7. A large predominance was observed for ST7, and genetic polymorphisms were confirmed at the intra-ST7 level with the identification of 5 divergent ST7 types. The incidence of both STs varied largely based on the breed, site, farm, and age. This is the first large-scale study to explore the prevalence and genetic characteristics of Blastocystis in chickens in China. The widespread distribution and avian adaptation of both zoonotic subtypes were demonstrated. The findings of this study highlight a potential threat to humans and will provide a better understanding of the epidemiology and public health impact of poultry Blastocystis.
肠道原生动物寄生虫包囊虫在全球范围内的人类和动物中都有报道，包括家禽，它可以引起包囊虫病的人畜共患传播。然而，目前在中国鸡中关于包囊虫的流行率、亚型分布和人畜共患潜力的综合信息尚不清楚。在这项研究中，从广东省 5 个城市的 43 个农场收集了 4 个品种的自由放养肉鸡的 1000 个个体粪便样本，以调查包囊虫感染的发生情况。通过小亚基核糖体 RNA (SSU rRNA) 基因的巢式 PCR 分析来确定包囊虫。鸡样本的总流行率为 20.1%（201/1000），筛查农场的流行率为 69.8%（30/43），不同农场之间的流行率存在显著差异，范围为 0 至 76.9%。评估了地点、品种和年龄对肉鸡中包囊虫的种群差异。在阳江（35.8%，38/106）、三黄鸡（29.7%，104/350）和 >80 日龄鸡群（30.5%，40/131）中观察到最高的感染率。DNA 测序和系统发育分析确定了 2 种人畜共患病亚型，ST6 和 ST7。ST7 占主导地位，在 ST7 水平上确认了遗传多态性，并鉴定了 5 种不同的 ST7 类型。两种 ST 的发生率因品种、地点、农场和年龄而异。这是首次在中国大规模研究鸡中包囊虫的流行率和遗传特征。证明了两种人畜共患病亚型的广泛分布和禽类适应性。本研究的结果突出了对人类的潜在威胁，并将更好地了解禽源包囊虫的流行病学和公共卫生影响。
