文献类型： 外文期刊

作者： Yan, Xiaofei ¹ ; He, Sangang ² ; Liu, Yiyong ³ ; Han, Bing ² ; Zhang, Ning ² ; Deng, Haifeng ⁴ ; Wang, Yuqi ⁵ ; Liu, Mingjun ² ;

作者机构： 1.Xinjiang Agr Univ, Coll Life Sci, Urumqi 830052, Peoples R China

2.Minist Agr, Xinjiang Key Lab Anim Biotechnol, Key Lab Genet Breeding & Reprod Herbivorous Livest, Inst Biotechnol,Xinjiang Acad Anim Sci, Urumqi, Xinjiang, Peoples R China

3.Anim Husb Terminus, Yining, Xinjiang, Peoples R China

4.Zhaosu Horse Farm, Zhaosu, Xinjiang, Peoples R China

5.Xinjiang Agr Univ, Coll Vet Med, Urumqi 830052, Peoples R China

关键词： Kazakh sheep; Gastrointestinal nematodes; Molecular epidemiology; Phylogenesis; The second internal transcribed spacer of ribosomal DNA

期刊名称：EXPERIMENTAL PARASITOLOGY （ 影响因子：2.1； 五年影响因子：2.1 ）

ISSN： 0014-4894

年卷期： 2023 年 254 卷

页码：

收录情况： SCI

摘要： Gastrointestinal nematode (GIN) infection in sheep has been recognized globally as a major problem challenging animal health and production. The objective of this study is to use a molecular diagnosis of the prevalence for gastrointestinal nematode (GIN) dominant species of Kazakh sheep and its hybrid (Kazakh x Texel). The internal transcribed spacer 2 (ITS-2) sequences of ribosomal DNA (rDNA) were used as the target sequence. In the study, three dominant species of nematodes, namely Haemonchus contortus, Trichostrongylus spp., and Teladorsagia (Ostertagia) circumcincta from the Kazakh sheep and the F1 and F2 generations of Texel x Kazakh sheep hybrids were subjected to molecular identification and phylogenetic analysis. The fecal and single larva genomic DNA were extracted and amplified by PCR using specific primers to determine the infection rate of the three nematode species. In addition, the PCR products were sequenced and analyzed using bioinformatics methods to construct a phylogenetic tree. The results showed that all the three species had their ITS-2 specific amplified. According to the sequence homology analysis of PCR products, the results showed a high homology (above 98.5% homology) with H. contortus, Trichostrongylus spp., T. circumcincta ITS-2 sequences in GenBank. Phylogenetic analysis showed that the ITS-2 sequences of the three species were on the same branch as the ITS-2 sequences of the same species in NCBI. And on different branches from those of the ITS-2 sequences of different families, genera and species. Sequences carried out on three species from different samples showed a close relationship and little genetic difference in phylogenetic tree. The infection rates based on fecal DNA were 35.59, 25.55, and 11.24% for H. contortus, Trichostrongylus spp., and T. circumcincta, respectively. While the infection rates based on larva DNA, were 24.07, 18.89, and 13.26% for H. contortus, Trichostrongylus spp., and T. circumcincta, respectively. The seasonal prevalence of the three dominant species in spring was significantly higher than that in autumn and winter. And there was no significant difference between Kazakh, F1 and F2 sheep considering the infection rate of the studied three species of nematodes. This study provides valuable molecular approaches for epidemiological surveillance and for assisting in the control of Nematodirus infection in sheep.