奶牛乳源大肠杆菌耐药性、毒素基因鉴定及PFGE分型研究  

Study on Antibiotic Resistance,Virulence Toxin Genes and PFGE Patterns of Escherichia coli Strains Isolated from Dairy Cattle Milk

作　　者：王晓[1] 王新[2] 郝丹[2] 唐晓双[2] 周传丽[1] 王雅春[1] 张胜利[1] 张沅[1] 俞英[1] 

机构地区：[1]中国农业大学动物科技学院,北京100193 [2]西北农林科技大学食品学院,杨凌712100

出　　处：《畜牧兽医学报》2014年第3期463-470,共8页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：国家自然科学基金(31272420);农业部奶业体系项目(CARS-37-04B);十二五国家科技支持项目(2011BAD28B02);长江学者与创新团队发展计划(IRT1191)

摘　　要：通过采集中国北方地区某荷斯坦牛场生产群牛及乳房炎牛197份样品(195份奶样及2份洗布水样),分离出28株大肠杆菌菌株,并进行细菌药敏试验、毒力基因检测及PFGE分型,为牛场防治大肠杆菌型乳房炎提供数据支持。检测28株大肠杆菌对35种抗生素的敏感性发现,兽用临床抗生素庆大霉素和大观霉素应作为该奶牛场大肠杆菌型乳房炎的主要治疗药物。但该牛场出现了对非兽用广谱抗生素麦迪霉素的耐受性菌株,提示牛场在治疗奶牛大肠杆菌型乳房炎时应该注意用药问题。同时,洗布水样分离出的大肠杆菌的多重耐药性较强,也应引起重视,以便及时切断病菌传播途径。基于本研究在28株大肠杆菌中Ecs3703毒力基因的检出率为100%,证实所分离的大肠杆菌为肠出血性大肠杆菌(EHEC)而非肠毒素大肠杆菌(ETEC)。细菌毒力基因Irp2和CNF2的检出则暗示携带这两类毒力基因的大肠杆菌极可能为奶牛乳房炎致病菌。The aim of this study was to investigate bacterial antibiotic resistance,virulence genes and PFGE patterns of 28 Escherichia coli strains isolated from 197samples(including 195milk samples,and 2cloth towel water samples that were used for cleaning cow teats)from a Northern Chinese Holstein farm.Antimicrobial susceptibility testing results of the 28 E.coli strains to 35 antibiotics showed that gentamicin and spectinomycin could be used as common clinical veterinary antibiotics in this farm.However,special attention should be paid to the emergence of broad-spectrum medemycin resistance in this farm.Since E.coli strains isolated from cloth towel water samples also had strong resistance to antibiotics,the farm manager should take actions to prevent cloths towel transferring mastitis.For the 28 E.coli strains,the detectable rate of virulence gene Ecs3703was 100%,which implied that they are Enterohemorrhagic E.coli(EHEC)rather thanEnterotoxigenic E.coli(ETEC).And those E.coli strains which carry virulence genes Irp2and/ or CNF2might be the main pathogen of dairy cattle mastitis.

关 键 词：中国荷斯坦牛 大肠杆菌 药敏试验 毒力基因 PFGE分型 

分 类 号：S858.23[农业科学—临床兽医学]