猪源霍氏肠杆菌的分离鉴定及其耐药性、致病性分析  

Isolation and Identification,Drug Resistance and Pathogenicity Analysis of Enterobacter hormaechei from Pigs

作　　者：李娜娜 余星雨 侯宫明珠 李扬 郭亚奇 郑培 李彦芳[1] 梁晏[1] 何高明[1] 屈勇刚[1] LI Nana;YU Xingyu;HOU Gongmingzhu;LI Yang;GUO Yaqi;ZHENG Pei;LI Yanfang;LIANG Yan;HE Gaoming;QU Yonggang(College of Animal Science and Technology,Shihezi University,Shihezi 832003,China;Tiankang Animal Husbandry Technology,Shihezi 832003,China)

机构地区：[1]石河子大学动物科技学院,石河子832003 [2]天康畜牧科技有限公司,石河子832003

出　　处：《中国畜牧兽医》2025年第1期376-388,共13页China Animal Husbandry & Veterinary Medicine

基　　金：新疆生产建设兵团重大科技项目“揭榜挂帅”(2022AA004);兵团自然科学支持计划项目(2024DA007)。

摘　　要：[目的]探究新疆伊犁某规模化猪场霍氏肠杆菌的耐药特征及致病性,为霍氏肠杆菌的防治提供参考。[方法]对采集的猪肛拭子、鼻拭子样品进行细菌分离与纯化,通过革兰染色及形态学观察、菌落形态特征、生化特性、种属特异性检测、16S rRNA测序分析对其进行鉴定;采用K-B法测定分离株对20种常用抗菌药物的敏感性;利用PCR方法检测分离株携带耐药基因和毒力基因情况,并通过动物试验分析其致病性;采用玻璃管法和微量滴定板法测定分离株的生物被膜形成能力。[结果]试验成功分离获得1株细菌,并命名为H1,该分离株在营养琼脂培养基上可形成表面凸起、光滑、湿润的乳白色菌落;革兰染色后菌体呈红色短杆状,散在排列。生化鉴定结果显示,分离株的葡萄糖、乳糖、尿素等生化试验均呈阳性;硫化氢、苯丙氨酸等生化试验均呈阴性。PCR扩增结果显示,Eh特异性基因、16S rRNA分别扩增出487、1 476 bp的目的条带;测序比对结果显示分离株与霍氏肠杆菌的相似性达100%,综合判定分离株H1为霍氏肠杆菌。分离株对恩诺沙星、氟苯尼考、复方新诺明等15种药物耐药,对多黏菌素B、环丙沙星等5种抗菌药物敏感,携带bla_(CTX-M-1)、tem、sul1、sul2、sul3、tetA、tetM、qnrB 8种耐药基因以及fimA、csdg、papD、ompA、cpa 5种毒力基因。动物致病性试验结果显示,分离株对小鼠具有一定的致病性,感染后引起十二指肠、肝脏、脾脏和肾脏损伤,具有较强的生物被膜形成能力。[结论]本研究分离获得1株霍氏肠杆菌,其表现多重耐药,携带多种耐药基因和毒力基因,对小鼠有一定的致病性,生物被膜形成能力强。试验结果为猪霍氏肠杆菌的防控提供了科学依据。[Objective]The purpose of this experiment was to investigate the resistance characteristics and pathogenicity of Enterobacter hormaechei in a large-scale pig farm in Yili,Xinjiang,and provide reference for the prevention and control of Enterobacter hormaechei.[Method]Bacteria was isolated and purified from the samples of anal and nasal swabs of pigs.The isolate was identified by Gram staining,morphological observation,colony morphological characteristics,biochemical characteristics,species-specific detection and 16S rRNA sequencing analysis.The sensitivity of the isolate to 20 commonly used antibiotics was determined by K-B method.The drug resistance genes and virulence genes were detected by PCR,and the pathogenicity was analyzed by animal test.The biofilm forming ability of the isolate was measured by glass tube method and microtitration plate method.[Result]A strain of bacteria was isolated and named H1.The isolate could form milky white colonies with protrusion,smooth and wet surface on the nutrient agar medium.Gram staining showed that the bacteria were red in short rod shape and scattered in arrangement.The results of biochemical identification showed that glucose,lactose,urea and other biochemical tests were positive,and hydrogen sulfide and phenylalanine were negative.PCR results showed that the target bands of Eh specific gene and 16S rRNA were 487 and 1476 bp,respectively.Sequencing results showed that the similarity between the isolated strain and Enterobacter hormaechei reached 100%,and the isolated H1 was comprehensively determined to be Enterobacter hormaechei.The isolate was resistant to 15 antibiotics,such as enrofloxacin,flufenicol and cotrimoxazole,and sensitive to 5 antibiotics,such as polycolistin B and ciprofloxacin.It carried 8 drug resistance genes(bla CTX-M-1,tem,sul 1,sul 2,sul 3,tetA,tetM and qnrB genes)and 5 virulence genes(fimA,csdg,papD,ompA and cpa genes).The results of animal pathogenicity test showed that the isolte was pathogenic to mice,causing duodenum,liver,spleen and kidney da

关 键 词：猪 霍氏肠杆菌 耐药性 致病性 

分 类 号：S852.65[农业科学—基础兽医学]