2019—2020年河北部分地区鸡源致病性大肠杆菌的血清型及毒力基因分布  

Serotypes and virulence gene distribution of pathogenic Escherichia coli from chickens in some areas of Hebei Province from 2019 to 2020

作　　者：张海龙 何云凤 党儒尧 陈玥 李佩国[1] 李蕴玉[1] ZHANG Hailong;HE Yunfeng;DANG Ruyao;CHEN Yue;LI Peiguo;LI Yunyu(Key Laboratory of Preventive Veterinary Medicine in Hebei Province,Hebei Normal University of Science and Technology,Qinhuangdao,Hebei 066604,China)

机构地区：[1]河北科技师范学院河北省预防兽医学重点实验室,河北秦皇岛066604

出　　处：《中国兽医学报》2022年第4期686-691,697,共7页Chinese Journal of Veterinary Science

基　　金：河北省现代农业产业技术体系蛋鸡产业创新团队岗位基金资助项目(HBCT2018150206)。

摘　　要：为确定河北部分地区鸡源致病性大肠杆菌(Escherichia coli,E.coli)的流行血清型及毒力基因变迁情况,本研究对2019—2020年来自河北部分地区的225份病死鸡组织样品,通过细菌分离纯化、PCR法共分离鉴定出181株致病性E.coli(2019年105株、2020年76株)。采用玻板凝集试验、PCR法对其进行血清型及毒力基因的研究,结果显示分离的菌株属于18种血清型,以O78(14.92%)、O1(14.36%)、O2(11.60%)、O18(10.50%)、O26(10.50%)为主要流行的血清型,其中2019年以O26、O1、O18、O78、O2血清型为主,检出率为7.62%~18.10%;2020年以O1、O2、O6、O9、O12血清型为主,检出率为7.89%~22.37%。分离菌株携带16种不同的毒力基因,未检测到Ler、eaeA、papC、sfa 4种毒力基因。其中2019年iutA毒力基因检出率最高,为96.19%(101/105);Vat、iutB、fyuA等9种毒力基因检出率为7.62%~76.19%;2020年的hlyF毒力基因检出率最高为100%;Vat、iutB毒力基因检出率较低,分别为2.63%和23.68%。分离菌株均携带多种毒力基因,其中2019年的菌株同时携带2~15种毒力基因;2020年的菌株同时携带4~15种毒力基因。优势血清型菌株的致病性试验结果发现,攻毒组的雏鸡发病率为100.00%,总病死率高达82.00%。本研究为河北部分地区鸡源E.coli的有效防控提供了科学依据。In order to determine the epidemiological serotypes and virulence gene changes of pathogenic Escherichia coli from chickens in some areas of Hebei Province,a total of 181 pathogenic Escherichia coli strains(105 in 2019 and 76 in 2020)were isolated and identified by PCR from 225 tissue samples of dead chickens in some areas of Hebei Province from 2019 to 2020.The serotypes and virulence genes of the isolates were studied by glass plate agglutination test and PCR.The results showed that the isolates belonged to 18 serotypes,of which O78(14.92%),O1(14.36%),O2(11.60%),O18(10.50%)and O26(10.50%)were the main prevalent serotypes.In 2019,the main serotypes were O26,O1,O18,O78 and O2,The detection rates ranged from 7.62% to 18.10%.In 2020,O1,O2,O6,O9 and O12 serotypes were the main serotypes,The detection rates ranged from 7.89% to 22.37%.The isolates carried 16 different virulence genes,while Ler,eaeA,papC and sfa were not detected.In 2019,the detection rate of iutA virulence gene was the highest,which was 96.19%(101/105).The detection rates of 9 virulence genes,such as Vat,iutB and fyuA ranged from 7.62% to 76.19%.In 2020,the maximum detection rate of hlyF virulence gene was 100%.The virulence gene detection rates of Vat and iutB were 2.63% and 23.68%,respectively.All the isolates carried a variety of virulence genes.In 2019,the strains carried 2-15virulence genes.In 2020,the strains carried 4-15virulence genes at the same time.Pathogenicity test of dominant serotype strains showed that the morbidity of chicks in challenge group was 100.00%,and the total mortality was 82.00%.This study provides a scientific basis for the effective prevention and control of E.coli from chickens in some areas of Hebei Province.

关 键 词：鸡大肠杆菌 血清型 毒力基因 毒力谱 

分 类 号：S855.1[农业科学—临床兽医学]