禽致病性大肠杆菌的分离、O血清群鉴定及药物敏感试验

对2005年5月~2016年3月自河北、山东、河南、江苏、陕西、辽宁等省发病鸡场疑似大肠杆菌病的病死鸡病变部位分离的194株禽致病性大肠杆菌进行了生化特性测定、O抗原血清群鉴定及药敏试验。试验用5种大肠杆菌单因子（O1、O2、O57、O65、O78）阳性血清进行O血清群鉴定，确定了124株O血清群，占鉴定菌株数的63.9%（124/194），其中O1 3株、O2 26株、O57 15株、O65 47株和O78 33株，O65和O78为优势菌株，而O2和O57血清群菌株次之，O1血清群菌株最少。8种药物（氨苄西林、新霉素、多西环素、磺胺间甲氧嘧啶、替米考星、环丙沙星、头孢噻呋和氟苯尼考）的药敏试验结果表明，受试的5株大肠杆菌分离株均对环丙沙星和新霉素敏感，而对其他药物均有不同程度的耐受。本研究结果表明O65、O78、O2和O57血清群高度流行，为进一步研发多价菌苗奠定了基础。

Isolation,O Serogrouping and Drug Sensitivity Test of Avian Pathogenic Escherichia coli

One hundred and ninety four avian pathogenic Escherichia.coli (APEC) isolated from different pathotypes of chickens in Hebei province,Shandong province,Henan province,Jiangsu province,Shanxi province and Liaoning province in China between May 2005 and March 2016 were investigated by determination of biochemical characters,O serogroup identification and drug sensitivity test.Out of 194 isolates, 124 strains(63.9%) could be grouped to serogroups O1(3),O2(26),O57(15),O65(47) and O78(33).The drug sensitivity test used eight antibiotics (ampicillin, neomycin, doxycycline, sulfamonomethoxine,tilmicosin,ciprofloxacin ceftiofur and florfenicol) by one strain of O1,O2,O57,O65,O78 serogroup,respectively.The results showed that all strains were sensitive to ciprofloxacin and neomycin, and resistance to other drugs at varying degrees.This study demonstrated that the high prevalence of O65,O78,O2 and O57 isolates existed and provided the basis for the development of multivalent bacterin in future.