致狐狸眼炎大肠杆菌的生物学特性检测与致病性分析  

Biological detection and pathogenicity analysis of Escherichia coli causing fox eye infection

作　　者：于莹 王少辉[2] 贺实伟 吕娇 韩坤[1] 白雪[1] 陈立志[1,3] YU Ying;WANG Shao-hui;HE Shi-wei;LU Jiao;HAN Kun;BAI Xue;CHEN Li-zhi(Institute of Special Animal and Plant Science , Chinese Academy of Agricultural Sciences , Changchun 130122, China;Institute of Shanghai Veterinary Rsearch, Chinese Academy of Agricultural Sciences , Shanghai 200241, China;Jilin Special Research Biological Technology Co. ,Ltd., Changchun 130122,China;College of Animal Science & Technology, Jilin Agricultural University, Changchun 130118,China)

机构地区：[1]中国农业科学院特产研究所,吉林长春130122 [2]中国农业科学院上海兽医研究所,上海200241 [3]吉林特研生物技术有限责任公司,吉林长春130122 [4]吉林农业大学动物科学技术学院,吉林长春130118

出　　处：《中国兽医科学》2019年第6期746-754,共9页Chinese Veterinary Science

基　　金：中国农业科学院基本科研业务费专项(Y2017CG34)

摘　　要：为确定辽宁省某狐狸养殖场致患病狐狸眼炎的病原菌,从患病狐狸眼部分离病原菌,并对分离株进行形态观察、生化试验、16S rRNA基因序列测定、血清分型及进化分群,在此基础上完成了毒力基因检测、药敏试验以及人工感染小鼠试验等。镜检结果显示,该细菌为革兰阴性短杆菌,最终鉴定结果可以确定此分离株为O25型大肠杆菌,并且2株菌均属于系统发育群B2群。毒力基因检测结果显示,其含有CNF-Ⅰ基因,无LT、K99、STa、SLT-Ⅰ、CNF-Ⅱ及EAE等毒力基因。人工感染小鼠试验显示,2株分离菌株均可引起小鼠眼睛发炎,化脓等疾病,其对小鼠的半数致死量(LD50)分别为3.60×10^6CFU/只、1.79×10^6 CFU/只。药敏试验表明,其对庆大霉素、环丙沙星、黏菌素及氯霉素耐药性较强,但对头孢噻肟、磺胺甲恶唑、四环素、左氧氟沙星、氟苯尼考及大观霉素等抗生素较为敏感。本研究结果为临床治疗由大肠杆菌引起的狐狸眼炎提供了重要依据。In order to determine the pathogens of the diseased foxes in Liaoning Province,the pathogens were isolated from the diseased eyes of foxes,and the isolates were subjected to morphological observation,biochemical test,16 S r RNA identification,molecular typing and phylogenetic group analysis.Basis on this,the virulence genes test,drug susceptibility test and artificial infection were completed.In result,the isolates were gram-negative,and the serogroups were O25,and both strains belonged to B2 group.The virulence genes test showed the isolates had CNF-Ⅰgene,and had no LT,K99,STa,STb,SLT-Ⅰ,CNF-Ⅱand EAE virulence genes.Tests on artificial infection showed that the isolates could cause eye inflammation,suppuration and other diseases in mice.The LD50 were 3.60 ×10^6 CFU/mice and1.79×10^6 CFU/mice.The drug sensitivity test showed that the isolates were highly resistant to gentamicin,ciprofloxacin,colistin and chloramphenicol,but sensitive to cefotaxime,sulfamethoxazole, tetracycline,levofloxacin,flufenicol and macroamycin.These study results provide an important basis for clinical treatment of ocular inflammatory disease caused by E.coli in foxes.

关 键 词：大肠杆菌 狐狸 血清型 毒力基因 药敏试验 

分 类 号：S852.612[农业科学—基础兽医学]