仔猪腹泻致病性大肠杆菌分型鉴定及耐药性分析

为了解贵州省规模化养猪场腹泻仔猪致病性大肠杆菌流行情况及耐药性变化,本研究运用凝集试验、PCR和药敏纸片琼脂扩散法等方法对分离的78株致病性大肠杆菌进行血清型、毒力基因及耐药性分析。结果显示,78株致病性大肠杆菌以O138、O87血清型为主,占定型菌株的60.8%;其中62株致病性大肠杆菌检出毒力基因,检出率为79.5%,可分为8种毒力基因类型,分属肠致病性大肠杆菌（EPEC）、肠产毒性大肠杆菌（ETEC）和肠聚集性大肠杆菌（EAEC）,毒力基因eaeA、elt和escV检出率较高,分别为38.5%、28.2%和21.8%;分离到的致病性大肠杆菌对β-内酰胺类药物高度耐药,均为多重耐药株,耐药种类可达8种以上。结果表明,当前贵州省规模化养猪场腹泻仔猪致病性大肠杆菌的毒力基因检出率较高且基因型复杂,耐药性严重。本试验结果可为规模化养猪场防控仔猪腹泻提供基础资料及理论依据。

Classification and Drug Resistance Analysis of Pathogenic Escherichia coli in Diarrhea Piglets

To understand the epidemic situation and drug resistance of pathogenic Escherichia coli (E.coli) in diarrhea piglets from large-scale swine farms in Guizhou province,agglutination test,PCR and drug sensitive agar diffusion methods were used to perform serotyping and virulence gene classification and drug resistance analysis of 78 pathogenic E.coli isolates in this experiment.The results showed that the main serotypes of 78 pathogenic E.coli were O138 and O87,accounting for 60.8% of the established strains;The virulence genes were detected in 62 strains of pathogenic E.coli,the detection rate was 79.5%,and could be divided into 8 virulence gene types,belonging to enteropathogenic E.coli (EPEC),enterotoxigenic E.coli (ETEC) and enterohemorrhagic E.coli (EAEC),respectively.The virulence genes eaeA,elt and escV had higher detection rate,which were 38.5%,28.2% and 21.8%,respectively.The isolated pathogenic E.coli was highly resistant to β-lactam drugs,and was multi-drug resistant,with more than 8 drug-resistant species.The results showed that the pathogenicity of E.coli in piglets with diarrhea in large-scale pig farms in Guizhou province was high,and the genotypes were complex.The pathogenicity of E.coli was severe.This experiment could provide basic data and theoretical basis for prevention and control of piglets diarrhea in large-scale pig farms.