【摘要】 调查某肉牛养殖场和其定点屠宰加工场中牛源大肠埃希菌的表型和基因型,为产业链中大肠埃希菌的污染情况提供科学依据。对分离鉴定的牛源大肠埃希菌采用O抗原多价血清进行检测,选取其中多价4和多价5的菌株进行单价PCR(O7、O39、O5、O114、O116、O6、O9、O30、O55)的扩增,同时进行ERICPCR的基因分型。结果表明,牛源大肠埃希菌分离株以多价4、多价5、多价6和多价19较多,检出率均超过5%。单价PCR检测出O5(2株)、O114(3株)、O116(4株)、O6(6株)、O9(2株)血清型。ERIC-PCR基因分型多价4和多价5中含有13种基因型,分成6簇,同源性在59%~100%。同种多价血清在一个簇,其中D簇包括12株菌,同源性在70%以上。然而同一种血清型的不同菌株其基因型不在一个簇内。更多还原

【Abstract】 To investigate the phenotype and genotype of Escherichia coli isolated from beef cattle farms and its designated slaughter and processing field,and to provide scientific basis for the pollution condition of E.coli in the industrial chain,the bovine E.coli was detected on the O antigen with polyvalent serum,the 4 and 5 polyvalent serum strains were selected and detected by PCR(O7,O39,O5,O114,O116,O6,O9,O30,O55)and ERIC-PCR genotyping.The results showed that 4,5,6,9 of polyvalent serotypes of the tested samples were dominant,all more than 5%.The PCR detection results were serotypes of the O5(2 strains),O114(3 strains),O116(4 strains),O6(6 strains),O9(2 strains).ERIC-PCR had 13 genotypes in 4 and 5 polyvalent serotypes,and can be divided into 6 clusters.The similarity was between 59%-100%.The same polyvalent serotype was in a cluster,the D cluster has the 12 strains and the similarity was over 70%.But the different strains in same serotype was not in same cluster genotypes.更多还原