河南地区猪源大肠杆菌分子分群、耐药性及生物被膜表型分析

摘要

为了解河南省豫西地区猪源大肠杆菌的流行病学及其主要生物学特性,本研究对2014年～2016年腹泻病猪无菌采集152份粪便样品,进行大肠杆菌的分离鉴定、系统进化分群、药物敏感性和生物被膜形成能力检测.结果采集的样品共分离到79株大肠杆菌,其中A群占46.84％(37/79),B1群占8.86％(7/79),B2群占27.85％(22/79),D群占16.46％(13/79).药物敏感性试验显示,分离的大肠杆菌对氨苄西林、氨曲南、庆大霉素、卡那霉素、利福平和克林霉素耐药,92.41％的大肠杆菌表现为多重耐药.79株大肠杆菌分为强成膜能力(26.58％)、中等成膜能力(31.65％)、弱成膜能力(27.85％)和无成膜能力(13.92％)4种表型.强生物被膜形成能力多属于大肠杆菌B2和D群,分别占分离株的31.82％和38.46％.生物被膜形成能力与分离菌株对氨苄西林、链霉素、复方新诺明、环丙沙星和庆大霉素的耐药性存在相关性.本研究为河南省猪源大肠杆菌病的防控和临床用药提供了实验依据.%To understand the epidemiology and main biological characteristics of Escherichia coli (E.coli) in pigs from Henan regions,152 fecal samples were collected from diarrhoea pigs from 2014 to 2016,and the isolation,identification,phylogenetic grouping analysis,drug sensitivity test and biofilm formation ability of E.coli in these fecal samples were conducted.The results showed there were 79 strains of E.coli were isolated from the 152 collected fecal samples,among which,46.84％ (37/79) belonged to the A group,8.86％ (7/79) belonged to the B1 group,27.85％ (22/79) belonged to the B2 group and 16.46％ (13/79) belonged to the D group.Drug susceptibility testing revealed that the isolates showed high resistance against ampicillin,aztreonam,gentamicin,kanamycin,rifampicin,and clindamycin,with 92.41％ of isolates exhibiting multidrug resistance.Various isolates had strong biofilm-formation ability (26.58％),moderate biofilm-formation ability (31.65％),and weak biofilm-formation ability (27.85％).Those with strong biofilm-forming ability were always pathogenic E.coli (groups B2 and D).The results also revealed that the biofilm formation ability was associated with the resistance of the isolates to ampicillin,streptomycin,compound novamoxin,ciprofloxacin,and gentamicin.This study provides crucial reference information for clinical treatment of swine colibacillosis in Henan region.