摘要
【目的】研究新疆羊源STEC的耐药性和毒力情况,评价羊源STEC在羊产业链饲养阶段的风险。【方法】从某规模化羊场随机采取2月龄羊的肛拭子样本,EC肉汤增菌后用MAC平板结合双重PCR(stx1,stx2)法分离鉴定STEC,用SMAC平板结合双重PCR(rfbE和fliC)法分离鉴定E.coli O157:H7;用K-B法做9类18种药的敏感试验,并用PCR检测相应的耐药基因;用PCR检测STEC的毒力基因(eae,ehxA,hlyA,stx1a,stx1c,stx1d,stx2a等),并检测是否“Top Six”和E.coli O157:H7血清型。【结果】被检的21只羊中,9只携带STEC(42.86%),其中1只羊还携带E.coli O157:H7;药敏试验显示仅有2株菌对头孢吡肟具有耐药性,对其他药均敏感;所有分离菌均携带stx1毒力基因,其毒力基因亚型以stx1a(60%)与stx1c(80%)为主,9株STEC不属于“Top Six”或O157血清型。【结论】该场羊源STEC的携带率较高,主要携带致病力较弱的stx1,有E.coli O157:H7,但是没有“Top Six”血清群;该场羊源STEC对目前的抗菌素普遍敏感,反映了其良好的养殖环境和较少的抗生素使用。
【Objective】To study the drug resistance and virulence of Shiga toxin-producing Escherichia coli from sheep in Xinjing.【Methods】Two-month-old sheep's anal swab samples were randomly taken from a large-scale farm.After the samples were enriched in EC broth,the Shiga toxin-producing Escherichia coli was isolated and identified by MAC plate combined with double PCR(stx1,stx2).E.coli O157:H7 was isolated and identified using SMAC plate in combination with double PCR.The susceptibility test of 9 types of 18 drugs was performed using the K-B method.Sensitivity test of 9 types of 18 drugs was conducted by K-B method,and corresponding drug resistance genes were detected by PCR.STEC virulence genes were detected by PCR and tested for"Top Six"and E.coli O157:H7 serotypes.【Results】Of the 21 samples,9 of them contained STEC(42.86%),and one of them contained E.coli O157:H7.Drug susceptibility test showed that only 2 strains were resistant to cefepime and sensitive to other drugs.All isolated strains carry the stx1 virulence gene,and their virulence gene subtypes are mainly stx1a(60%)and stx1c(80%).9 STECs are not part of the"Top Six"or O157 serotype.【Conclusion】From the separation of STEC in the sheep farm,STEC has a high carrying rate,mainly carrying stx1 with weak pathogenicity.The strain isolated from the farm contained the O157:H7 serotype but did not have"Top Six".The farm's STEC is generally sensitive to current antibiotics,reflecting its good aquaculture environment and less antibiotic use.
作者
张凌
佟盼盼
张毅
马晓玉
张萌萌
刘璐瑶
姚刚
陈童锦悦
苏战强
ZHANG Ling;TONG Panpan;ZHANG Yi;Ma Xiaoyu;ZHANG Mengmeng;LIU Luyao;YAO Gang;CHEN Tongjinyue;SU Zhanqiang(College of Veterinary Medicine,Xinjiang Agricultural University,Urumqi 830052, China)
出处
《新疆农业科学》
CAS
CSCD
北大核心
2020年第10期1921-1930,共10页
Xinjiang Agricultural Sciences
基金
新疆自治区建设专项(自然科学基金)面上项目(2019D01A51)
自治区重点研发计划(2017B01005-2-4)
新疆农业大学2019年度校级大学生创新项目(S201910758106)
国家自然科学基金(31560485)。
关键词
羊
产志贺毒素大肠杆菌
毒力基因亚型
耐药性
血清型
sheep
Shiga toxin-producing Escherichia coli
virulence gene subtype
drug resistance
serotypes
