目的结合鼠疫疫源地调查和监测工作对青海省海东市小型兽类体表寄生蚤的构成、宿主选择和分布进行调查研究,并应用分子生物学方法对部分常见和疑难蚤种进行分子鉴定,以提高蚤种分类鉴别准确性。方法应用细胞色素C氧化酶亚基Ⅰ（COⅠ）基因对蚤类进行分子鉴定,并结合传统形态学分类方法综合鉴别蚤类。结果海东市共发现和记录体表寄生蚤61种（亚种）,隶属4总科5科28属。测得4科13属20种计99条蚤COⅠ基因序列片段（约658 bp）,种内遗传距离为0.2%～2.9%,种间为3.3%～22.9%,种间距离明显大于种内。结论系统进化分析显示各蚤种单系的支持率均>99%,COⅠ基因和传统形态分类方法的结合可以更准确地鉴定海东市蚤类。
Objective To investigate the species composition,host selection,and distribution of ectoparasitic fleas on small mammals in Haidong,Qinghai Province,China based on plague foci surveillance data,and to identify the species of some common fleas and difficult-to-identify fleas by molecular method to find a way that can improve the accuracy of flea species identification and classification.Methods Flea species was identified by traditional morphological classification and molecular identification based on of the cytochrome c oxidase subunit Ⅰ (COⅠ) gene.Results A total of 61 species (subspecies) of ectoparasitic fleas were found and recorded in Haidong,belonging to 28 genera,5 families,and 4 superfamilies. The partial fragments (about 658 bp) of the COⅠ gene were sequenced for 99 fleas of 20 species under 13 genera and 4 families. The intraspecific and interspecific genetic distances were 0.2%-2.9% and 3.3%-22.9%, respectively. The interspecific distance was significantly greater than the intraspecific distance.Conclusion The flea species formed single lineages with support values greater than 99% in the phylogenetic tree,indicating that the combination of COⅠgene characterization and traditional morphological classification can accurately identify flea species in Haidong.
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