山羊肺源肠外致病型大肠杆菌和粘质沙雷氏菌混合感染的病原分离鉴定、毒力因子基因检测和耐药性分析  

Pathogen Isolation,Identification,Virulence Factor Gene Detection,and Drug Resistance Analysis of Mixed Infection with Extraintestinal Pathogenic Escherichia coli and Serratia marcescens in Goats

作　　者：徐海军[1] 张磊 爨淑楠 张娅菲 贾哲 张圣尧 王书明 XU Haijun;ZHANG Lei;CUAN Shunan;ZHANG Yafei;JIA Zhe;ZHANG Shengyao;WANG Shuming(College of Biological and Pharmaceutical Engineering,West Anhui University,Liuan 237012,China;Anhui Jinfengyuan Animal Husbandry Technology Co.,Ltd.,Liuan 237000,China)

机构地区：[1]皖西学院生物与制药工程学院,安徽六安237012 [2]安徽金丰源畜牧科技有限公司,安徽六安237000

出　　处：《中国兽医杂志》2024年第2期54-60,共7页Chinese Journal of Veterinary Medicine

基　　金：2022年安徽省重点研究与开发计划项目(202204c06020034);安徽省本科质量工程项目(2021jxtd311,2021jyxm1663)。

摘　　要：为了确定1例成年山羊突然急性死亡的原因,本试验采用病史调查、病理剖检、病原菌分离和鉴定明确细菌性病原,对分离菌进行致病性试验和药敏试验,并根据药敏试验结果对其余未发病山羊进行给药预防;对分离到的大肠杆菌进一步进行系统进化群分析和毒力因子基因检测。结果显示,死亡山羊剖检可见部分结肠肠段严重出血,心内膜有散在出血斑,瘤胃黏膜局部充血;从肺组织中分离获得大肠杆菌和粘质沙雷氏菌;致病性试验结果显示,大肠杆菌对小鼠的致死率为90%,粘质沙雷氏菌对小鼠无致病性;药敏试验结果显示,大肠杆菌对头孢曲松和丁胺卡那敏感,粘质沙雷氏菌对恩诺沙星、丁胺卡那、庆大霉素和磷霉素中度敏感;使用头孢噻呋钠和恩诺沙星注射液对其余未发病山羊进行预防性注射给药后,未再出现发病死亡。系统进化群分析显示,分离获得的大肠杆菌属于A群;毒力因子基因检测结果显示,该大肠杆菌携带2种毒力标记基因(afa和iutA),因此属于肠外致病型大肠杆菌,该菌还携带其他毒力因子基因(ompA、ompT、traT、iss、iroN、iucD、fimH和gafD);本试验结果可为山羊大肠杆菌和粘质沙雷氏菌混合感染的诊断和治疗提供参考。To determine the cause of sudden acute death in an adult goat,this study employed medical history investigation,pathological dissection,pathogen isolation and identification to confirm bacterial pathogens.Pathogenicity and drug sensitivity tests were conducted on the isolated strains.Subsequent to drug sensitivity results,preventative drug administration was performed on the remaining unaffected goats.Further,systematic evolutionary group analysis and virulence factor gene detection were carried out on the isolated Escherichia coli strains.The results revealed severe bleeding in the colonic segments,scattered endocardial hemorrhages,and localized congestion of the rumen mucosa in the dissected goat.Escherichia coli and Serratia marcescens were isolated from lung tissue.Pathogenicity test results showed a mortality rate of 90%for Escherichia coli in mice,while Serratia marcescens exhibited non-pathogenicity.Drug sensitivity tests demonstrated sensitivity of Escherichia coli to ceftriaxone and amikacin,and moderate sensitivity of Serratia marcescens to enrofloxacin,amikacin,gentamicin and fosfomycin.Preventative injection with cefoperazone sodium and enrofloxacin effectively prevented further morbidity and mortality in the remaining goats.Systematic evolutionary group analysis indicated that the isolated Escherichia coli belonged to group A.Virulence factor gene detection revealed that this strain of Escherichia coli was extraintestinal pathogenic Escherichia coli,carrying two virulence marker genes(afa and iutA),and other virulence genes(ompA,ompT,traT,iss,iroN,iucD,fimH and gafD).The results of this study provide valuable insights for the diagnosis and treatment of mixed infections with Escherichia coli and Pasteurella multocida in goats.

关 键 词：山羊 大肠杆菌 粘质沙雷氏菌 毒力因子 感染 

分 类 号：S855[农业科学—临床兽医学]