现代畜牧科技Issue(8)：14-18,5.DOI:10.19369/j.cnki.2095-9737.2024.08.003
和牛源致病性大肠杆菌的分离鉴定
Isolation and Identification of Wagyu-Originated pathogenicity Escherichia coli
摘要
Abstract
To investigate the cause of Wagyu calf diarrhea mortality,this study collected ten fresh fecal samples from diarrheic Wagyu calves in Longjiang County Qiqihar City,for bacterial isolation and culture,biochemical identification,and 16S rRNA gene sequencing.A single purified bacterial strain isolated from a diarrhea sample,was selected for pathogenicity tests,antimicrobial susceptibility testing,virulence gene detection,phylogenetic tree construction,and homology analysis.The results showed that all 10 pathogenic strains isolated from the samples were consistent with the growth morphology and biochemical characteristics of Escherichia coli,with an isolation rate of 100%.The test strain is named Wagyu.1,virulence gene detection revealed that K88,CS31A,BfpA,EAST1,and hlyA were positive.The 16S rRNA sequence showed 93.6%～99.9%homology with E.coli in GenBank.The phylogenetic tree indicated that Wagyu.1 and the human-derived E.coli strain 62-b pink(GenBank accession number:MN208129)in the same branch,exhibiting the closest phylogenetic relationship.The in vitro antimicrobial susceptibility test showed that the strain was most sensitive to cefotaxime and ceftazidime,The findings suggest that the isolate Wagyu.1 is a highly virulent pathogenic E.coli strain.The close phylogenetic relationship and homology with human-derived E.coli for Human-animal separation management and reduce disease incidence.关键词
和牛/致病性大肠埃希氏菌/分离鉴定/系统进化树/毒力基因Key words
Wagyu/pathogenicity E.coli/isolation and identification/phylogenetic tree/virulence gene分类
农业科技引用本文复制引用
兰世捷,沈思思,王志强,田秋丰,张备,苗艳,陈亮,朱庆贺,李丹,张蕾,于辰龙,丁丽艳,冯万宇..和牛源致病性大肠杆菌的分离鉴定[J].现代畜牧科技,2024,(8):14-18,5.基金项目
黑龙江省农业科学院畜牧兽医分院自拟课题(ZNKT-202209) （ZNKT-202209）
黑龙江省农业科学院畜牧兽医分院重点项目(ZNKT-2022-ZD030) （ZNKT-2022-ZD030）
