猪流行性腹泻病毒与产硫化氢大肠杆菌混合感染的实验室诊断  

Laboratory Diagnosis of Mixed Infection of Porcine Epidemic Diarrhea Virus and Escherichia Coli producing hydrogen sulfide

作　　者：刘京 赵雪[1] 王云霄 徐瑞涛[1] 宋勤叶[1] 李潭清[1] 高玉红[3] LIU Jing;ZHAO Xue;WANG Yun-xiao;XU Rui-tao;SONG Qin-ye;LI Tan-qing;GAO Yu-hong(College of Veterinary Medicine ,Agricultural University of Hebei ,Baoding 071000 ,China;The Center for Animal Disease Control and Prevention ,Baoding 071001,China;College of Animal Science and Technology ,Agricultural University of Hebei ,Baoding 071000 ,China)

机构地区：[1]河北农业大学动物医学院河北省兽用生物制品工程技术研究中心,河北保定071000 [2]保定市动物疫病预防控制中心,河北保定071001 [3]河北农业大学动物科技学院,河北保定071000

出　　处：《中国兽医杂志》2018年第11期35-38,42,I0003,共6页Chinese Journal of Veterinary Medicine

基　　金：国家重点研发计划(2016YFD0500703);河北省科技计划项目(17226613D-2);河北省留学人员资助项目(130601151)

摘　　要：为了明确某猪场初生仔猪腹泻的病因,应用PCR、核酸序列分析、细菌分离鉴定以及动物试验等方法,对该病例进行了实验室诊断。从病仔猪的肠道及其内容物中检测到了猪流行性腹泻病毒(PEDV) N蛋白基因,该基因片段与近年国内流行的PEDV变异株的同一性在99%以上。同时从病猪的肝脏和脾脏中分离到了致病性大肠杆菌,该分离株具有一般大肠杆菌的形态特征、培养特性和生化特点,但产生H_2S,其16S rRNA基因序列与已知大肠杆菌的同源性高达99.9%。遗传进化分析表明,分离菌株与产肠毒素性大肠杆菌(ETEC)处于同一分支。BALB/c小鼠(n=8)经腹腔感染分离菌株5 h开始死亡,至感染后20 h,感染小鼠全部死亡。此外,该大肠杆菌分离株只对多黏菌素B敏感,对常用的第3代头孢菌素类药物中介,而对其他常用的多种氨基糖苷类、喹诺酮类药物以及复方新诺明等多种药物耐药。In order to investigate the cause of neonatal piglet diarrhea in one pig farm, the laboratory diagnosis was implemented using polymerase chain reaction (PCR), nucleotide sequence analysis, isolation and identification of bacteria and animal experiment. N protein gene of porcine epidemic diarrhea virus (PEDV) was detected from the intestinal tract and content of the sick piglets, and the amplified nucleotide acid sequence identity between PEDV in this study and PEDV variants published was more than 99%. And then, pathogenic Escherichia coli (E. coli) was isolated from livers and spleens of dead piglets. This isolate produced hydrogen sulfide and possessed similar morphological, cultural and biochemical characteristics to common E. coli. The identity of 16S rRNA genetic sequences reached 99. 9% between the E. coli isolate and the known strains, and the isolate was in the same branch as the enterotoxigenic E. coli (ETEC) on phylogenetic tree based on 16S rRNA gene. Balb/ c mice began to die at 5 h, and all of the mice died within 20 h after infected by the E. coli isolate. In addition, the isolate was only susceptible to polymyxin B, intermediate to the third generation of cephalosporins frequently-used, and resistant to multiple drugs including aminoglycosides, quinolones and trimethoprim.

关 键 词：初生仔猪 猪流行性腹泻病毒 产H2S大肠杆菌 混合感染 

分 类 号：S855.3[农业科学—临床兽医学]