摘要
2021年3—4月份,河南省某兔场家兔连续出现精神不振、食欲减退及腹泻症状,发生腹泻2~3 d后死亡。为了确定引起该兔场家兔感染的病原菌及筛选有效的治疗药物,无菌采集病死兔的肝脏、肺脏及肠道等具有典型病变的组织样品进行细菌的分离培养、革兰氏染色、生化试验、PCR鉴定及小鼠致病性试验,并对分离到的菌株进行药敏试验。结果表明:通过对病死兔器官组织分离培养及生化鉴定,得到一株革兰氏阴性短杆菌和一株革兰氏阳性球菌,初步判定分离菌为大肠杆菌和金黄色葡萄球菌,分别命名为HN-X01和LY-X01。HN-X01株eaeA基因和LY-X01株16S rDNA基因PCR扩增分别得到833 bp和480 bp大小的目的条带,与预期结果相符。测序结果经比对分析显示,分离菌株HN-X01与大肠杆菌参考株的核苷酸相似性为96.20%~97.07%,分离菌株LY-X01与金黄色葡萄球菌参考株的核苷酸相似性为99.53%~99.91%。小鼠注射分离菌株HN-X01后在48 h内全部死亡,注射LY-X01后在72 h内死亡率为75%,表明分离菌株HN-X01、LY-X01均具有一定毒力。两种分离菌株对头孢哌酮均表现敏感,对环丙沙星、哌拉西林均表现中介,对青霉素、红霉素、卡那霉素等均表现耐药。说明此次兔场暴发的疾病由大肠杆菌和金黄色葡萄球菌混合感染引起,且这两种分离菌株对多种抗生素具有耐药性。
In March and April 2021, rabbits in a rabbit farm in Henan Province continuously showed signs of mental depression, loss of appetite and diarrhea, and died after 2-3 d of diarrhea. In order to determine the pathogenic bacteria which caused the infection of rabbits in this rabbit farm and to screen out effective therapeutic drugs, samples from the liver, lung, intestinal tract and other typical lesions of dead rabbits were collected aseptically for bacteria isolation and culture, Gram staining, biochemical test, PCR identification and mouse pathogenicity test;and drug sensitivity test was conducted on the isolated strains. The results showed that one strain of Gram negative short bacilli and one strain of Gram positive cocci were obtained through isolation, culture and biochemical identification of organs and tissues of dead rabbits. It was preliminarily determined that the isolated bacteria were Escherichia coli and Staphylococcus aureus, named HN-X01 and LY-X01 respectively. PCR amplification results of eaeA gene of the isolate HN-X01 and 16S rDNA gene of the isolate LY-X01 showed that 833 bp and 480 bp target bands were amplified, which was consistent with the expected results. The sequencing results showed that the nucleotide similarity between the isolate HN-X01 and reference strains of Escherichia coli was 96.20%-97.07%, and that between the isolate LY-X01 and reference strains of Staphylococcus aureus was 99.53%-99.91%. All mice died within 48 h after challenge after injection of the isolated strain HN-X01, and the death rate within 72 h after injection of LY-X01 was 75%, indicating that the isolated strains HN-X01 and LY-X01 had certain toxicity. Both isolates were sensitive to cefoperazone, intermediate to ciprofloxacin and piperacillin, and resistant to penicillin, erythromycin and kanamycin. The results suggested that the disease outbreak in the rabbit farm was caused by the mixed infection of Escherichia coli and Staphylococcus aureus, and both isolated bacteria were resistant to many antibiotics.
作者
徐靖怡
刘玉梅
王佳佳
乔垒
吕琼霞
陈晓光
张自强
XU Jingyi;LIU Yumei;WANG Jiajia;QIAO Lei;LYU Qiongxia;CHEN Xiaoguang;ZHANG Ziqiang(College of Animal Science and Technology,Henan University of Science and Technology,Luoyang 471000,China;Henan Provincial Huaxing Agriculture and Animal Husbandry Development Co.,Ltd.,Zhumadian 463000,China)
出处
《黑龙江畜牧兽医》
CAS
北大核心
2023年第6期70-75,141,142,共8页
Heilongjiang Animal Science And veterinary Medicine
基金
河南省重点研发与推广专项(192102110077
202102110093)
河南省高等学校青年骨干教师项目(2019GGJS080)。
关键词
兔
大肠杆菌
金黄色葡萄球菌
腹泻
药敏试验
rabbits
Escherichia coli
Staphylococcus aureus
diarrhea
drug sensitivity test
作者简介
徐靖怡(1998-),女,硕士研究生,研究方向为家免疾病预防和治疗,200320251216@stu.haust.edu.cn;通信作者:张自强(1978-),男,副教授,博士,硕士生导师,研究方向为家兔的疾病防控和动物细胞治疗,ziqiangzhang@haust.edu.cn.
