中国兽医杂志2024，Vol.60Issue(8)：18-23,6.DOI:10.20157/j.cnki.zgsyzz.2024.08.003
羊腹泻大肠杆菌整合子及ESBLs携带情况检测
Detection of Integrons and ESBLs in Diarrheagenic Escherichia coli from Sheep
摘要
Abstract
To determine the resistance mechanisms of diarrheagenic Escherichia coli in sheep in Inner Mongolia Autonomous Region,this study utilized PCR methods to detect integrase genes(types Ⅰ,Ⅱ,Ⅲ),resistance gene cassettes,and genes encoding extended-spectrum β-lactamases(ESBLs)in bacterial strains isolated from farms around Hohhot.The results showed that out of 108 diarrheagenic E.coli strains from sheep,42 strains tested positive for type Ⅰ integrase genes and resistance gene cassette insertion regions,with a detection rate of 38.9％.Type Ⅱ and Ⅲ integrase genes were not detected.Five types of gene cassettes were prevalent among the strains,mainly carrying resistance genes for trimethoprim(dfr)and aminoglycosides(aadA).The blaTEM gene was detected in 83 strains(76.9％),while blaSHV and blaCTX genes were not amplified by PCR.Plasmid DNA successfully amplified blaTEM-type ESBLs genes in 40 strains of type Ⅰ integron-positive bacteria.The results indicate a high carriage rate of type Ⅰ integrons in diarrheagenic E.coli from sheep in Inner Mongolia.The resistance of these strains to sulfonamides,trimethoprim,and aminoglycosides is closely related to the carried resistance gene cassettes.The production and dissemination of ESBLs in these isolates are mediated by their plasmids,which may be the main reason for their resistance to β-lactam antibiotics.The widespread distribution of type Ⅰ integrons in ESBL-positive strains also facilitates the dissemination of resistance genes carried by these bacteria.This study analyzes the production and transmission of antibiotic resistance in diarrheagenic E.coli from sheep to guide clinical rational drug use.关键词
腹泻大肠杆菌/羊腹泻/Ⅰ型整合子/耐药基因盒/超广谱β-内酰胺酶(ESBLs)Key words
diarrheagenic E.coli/sheep diarrhea/type Ⅰ integron/resistance gene cassette/extended-spectrum β-lactamases(ESBLs)分类
农业科技引用本文复制引用
宋晨,苏建国,郝普国,顾珂瑞,王琪,徐文琦,樊宏亮,赵红霞..羊腹泻大肠杆菌整合子及ESBLs携带情况检测[J].中国兽医杂志,2024,60(8):18-23,6.基金项目
内蒙古自治区科技重大专项(2021ZD0013) （2021ZD0013）
内蒙古自治区高等学校科学研究项目(NJZY21451) （NJZY21451）
