猪肠外致病性大肠埃希菌的分离鉴定及部分生物学特性研究

Isolation,identification of pathogenic escherichia coli isolated from pigs and reseach on portion biological characteristics

为了查明引起广西某猪场仔猪腹泻及致死的原因,试验采用常规方法进行细菌分离鉴定,同时对分离菌株进行耐药性及毒力基因检测。通过16SrDNA、细菌生化鉴定及小鼠致病性试验等方法进行检测。结果分离获得一株肠外致病性大肠埃希菌。药敏试验结果表明该菌株对头孢西丁、庆大霉素极度敏感,对妥布霉素、新霉素等4种药物高度敏感,对青霉素G、四环素、链霉素等12种药物耐药,经耐药基因筛查发现,该菌株仅存在有氨基糖苷类和磺胺类耐药基因。毒力基因检测为iucD+papC+fyuA+iss+kspM+毒力型。说明此次疫情由猪肠外致病性大肠埃希菌引起。

In order to find out the causes of diarrhea and death of piglets in a pig farm in Guangxi,the diseased tissues of dead pigs were collected,and the bacteria were isolated and identified by routine methods and virulence gene.A strain of enterogenic escherichia coli was isolated by 16 SrDNA,bacterial biochemical identification and animal’s pathogenicity test.Drug susceptibility test results showed that the bacteria present drug hypersensitivity with cefoxitin,gentamicin,present highly sensitive with tobramycin,neomycin,and other 4 kinds of drugs,and prensent drug resistance with penicillin G,tetracycline,streptomycin and other 12 kinds of drugs.And from the resistant gene screening,We found that the strain only exist aminoglycoside and sulfa drug resistance gene.The virulence gene was detected as iucD+papC+fyuA+iss+kspM+virulence.Studies have shown that the outbreak was caused by pathogenic E.coli in pigs.