摘要
为调查新疆 4 个地区马源大肠杆菌的携带情况,采集 56 份马粪便样本进行大肠杆菌分离鉴定,采用药敏纸片法和结晶紫微孔板法对分离株进行相关特性测定,并对其毒力基因和耐药基因进行检测.结果显示:从 56 份样本中分离到 41 株大肠杆菌,分离率为 73.2%(41/56);分离株对利福平(97.6%)、头孢噻吩(46.3%)、复方新诺明(29.3%)、四环素(24.4%)和氯霉素(19.5%)等表现出不同程度的耐药性;分离株中,生物被膜形成能力中等的有 7 株(17.1%,7/41),弱的有 32 株(78.0%,32/41),不形成的有 2 株(4.9%,2/41);从 16 种毒力基因中,共检出fimC(87.8%,36/41)、fyuA(58.5%,24/41)、irp2(41.5%,17/41)、sepA(36.6%,15/41)和hlyF(22.0%,9/41)5种毒力基因;从11种耐药基因中,共检出parC、gyrA和gyrB(100.0%,41/41),sul2(31.7%,13/41)、floR(22.0%,9/41)、blaTEM(22.0%,9/41)、blaCTX(12.2%,5/41)和aadA(2.4%,1/41)8 种耐药基因.结果表明:新疆 4 个地区的马源大肠杆菌针对不同抗生素具有不同程度的耐药性,此外,这些菌株可形成生物被膜,并且携带有多种毒力基因和耐药基因.为新疆马源大肠杆菌病的临床用药和防治提供了试验数据.
Abstract
To investigate the presence of Escherichia coli in specific areas of Xinjiang,56 stool samples were collected from horse farms,which were confirmed to be connected with E.coli.The drug-sensitive paper method and the microporous crystal violet plate method were used to determine the characteristics of the isolates,and their virulence and resistance genes were detected.The results revealed that 41 out of 56 samples yielded E.coli strains,indicating an isolation rate of 73.2%(41/56).The isolates exhibited varying degrees of resistance to rifampicin(97.6%),cefathiophene(46.3%),cotrimoxazole(29.3%),tetracycline(24.4%)and chloramphenicol(19.5%).Furthermore,7 isolates demonstrated moderate biofilm forming ability(17.1%,7/41),32 isolates had weak biofilm forming ability(78.0%,32/41),and 2 isolates had no biofilm forming ability(4.9%,2/41).Among the 16 examined virulence genes,5 were detected in the isolates,including fimC(87.8%,36/41),fyuA(58.5%,24/41),irp2(41.5%,17/41),sepA(36.6%,15/41)and hlyF(22.0%,9/41).Additionally,11 drug resistance genes were analyzed,and 8 drug-resistant genes parC,gyrA,and gyrB were identified in all isolates(100.0%,41/41).Other detected drug resistance genes included sul2(31.7%,13/41),floR(22.0%,9/41),blaTEM(22.0%,9/41),blaCTX(12.2%,5/41)and aadA(2.4%,1/41).This study provides valuable experimental data on the levels of antibiotic resistance,biofilm-forming ability,and the presence of virulence and drug resistance genes in equine E.coli from various regions of Xinjiang.These findings contribute to the understanding and potential clinical treatment and control of equine colibacillosis in Xinjiang.
基金项目
新疆生产建设兵团重点领域科技攻关计划(2020AB025)
塔里木大学校长基金(博士)胡杨英才项目(TDZKB-S202307)