College of Veterinary Medicine, Inner Mongolia Agricultural University, Hohhot, China.
Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease, Ministry of Agriculture and Rural Affairs, Hohhot, China.
Sci Rep. 2023 Aug 26;13(1):13960. doi: 10.1038/s41598-023-40987-9.
Giardia duodenalis is a gastrointestinal protozoan ubiquitous in nature. It is a confirmed zoonotic pathogen, and cattle are considered a source of giardiasis outbreaks in humans. This study aimed to evaluate the prevalence and multilocus genotype (MLG) of G. duodenalis in dairy cattle in Central Inner Mongolia. This study was based on the small subunit ribosomal RNA (SSU rRNA), glutamate dehydrogenase (gdh), triosephosphate isomerase (tpi), and beta-giardin (bg) genes of G. duodenalis. DNA extraction, polymerase chain reaction (PCR), and sequence analysis were performed on 505 dairy cattle fecal samples collected in 2021 from six sampling sites and four age groups in Central Inner Mongolia to determine the prevalence and MLG distribution of G. duodenalis. The PCR results of SSU rRNA revealed that the overall prevalence of G. duodenalis was 29.5% (149/505) and that the overall prevalence of the diarrhea and nondiarrhea samples was 31.5% (46/146) and 28.5% (103/359), respectively; the difference was not significant (p > 0.05). SSU rRNA sequence analysis revealed that G. duodenalis assemblage E (91.1%, 133/146) was primarily detected and that assemblage A (8.9%, 13/146) was detected in 13 samples. The G. duodenalis-positive samples were PCR amplified and sequenced for gdh, tpi, and bg, from which 38, 47, and 70 amplified sequences were obtained, respectively. A combination of G. duodenalis assemblages A and E were detected in seven samples. Multilocus genotyping yielded 25 different assemblage E MLGs, which formed six subgroups. To the best of our knowledge, this is the first report regarding G. duodenalis infection in dairy cattle in Inner Mongolia, China. This study revealed that Inner Mongolian cattle pose a risk of giardiasis transmission to humans and that the distribution of local cattle G. duodenalis assemblage E MLGs is diverse. The findings of this study can bridge the knowledge gap in the molecular epidemiological investigation of giardiasis in Central Inner Mongolia.
十二指肠贾第鞭毛虫是一种普遍存在于自然界中的胃肠道原生动物。它是一种已确认的人畜共患病病原体，牛被认为是人类贾第鞭毛虫病爆发的源头。本研究旨在评估内蒙古中部地区奶牛中贾第鞭毛虫的流行率和多位点基因型（MLG）。本研究基于贾第鞭毛虫的小亚基核糖体 RNA（SSU rRNA）、谷氨酸脱氢酶（gdh）、磷酸丙糖异构酶（tpi）和β-微管蛋白（bg）基因。从内蒙古中部六个采样点和四个年龄组采集的 2021 年 505 份奶牛粪便样本中提取 DNA，进行聚合酶链反应（PCR）和序列分析，以确定贾第鞭毛虫的流行率和 MLG 分布。SSU rRNA 的 PCR 结果显示，贾第鞭毛虫的总流行率为 29.5%（149/505），腹泻和非腹泻样本的总流行率分别为 31.5%（46/146）和 28.5%（103/359），差异无统计学意义（p>0.05）。SSU rRNA 序列分析显示，主要检测到贾第鞭毛虫组 E（91.1%，133/146），在 13 个样本中检测到组 A（8.9%，13/146）。对 G. 十二指肠阳性样本进行 gdh、tpi 和 bg 的 PCR 扩增和测序，分别获得 38、47 和 70 个扩增序列。在 7 个样本中检测到 G. 十二指肠组 A 和 E 的组合。多位点基因分型产生了 25 种不同的组 E MLG，它们形成了六个亚群。据我们所知，这是中国内蒙古首次报道奶牛感染贾第鞭毛虫。本研究表明，内蒙古牛有向人类传播贾第鞭毛虫病的风险，本地牛贾第鞭毛虫组 E MLG 的分布是多样的。本研究的发现可以填补内蒙古中部贾第鞭毛虫分子流行病学研究的知识空白。
