鲮鱼致病性迟钝爱德华氏菌的鉴定及药敏分析  

Identification and Analysis of Antibiotic Sensitivity of Pathogenic Bacterium Edwardsiella tarda from Cultured Mud Carp(Cirrhinus molitorella)

作　　者：陈言峰[1] 卓孝磊 王超 郑宗正 付强[1] CHEN Yanfeng ZHUO Xiaolei WANG Chao ZHENG Zongzheng FU Qiang(College of Life Science and Engineering, Foshan University, Foshan 528231, China Qingyuan North River Fishery Science Institute,Qingyuan 511510, China Epidemic Prevention Station of Aquatic Animal in Qingyuan City, Qingyuan 511510, China)

机构地区：[1]佛山科学技术学院生命科学与工程学院,广东佛山528231 [2]清远市北江水产科学研究所,广东清远511510 [3]清远市水生动物防疫检验站,广东清远511510

出　　处：《水产科学》2017年第1期48-53,共6页Fisheries Science

基　　金：广东省自然科学基金资助项目(2014A030310020);广东高校优秀青年创新人才培养计划项目(2014KQNCX183);佛山科学技术学院优秀青年教师培养计划项目(fsyq201507)

摘　　要：自广东省清远市某养殖场患病鲮鱼的肝、肾、脾组织分离到两株优势菌QY15814、QY15815,通过细菌生化鉴定管与16SrDNA序列分析对这两株菌进行鉴定,采用纸片扩散法进行药敏试验,并测定了这两株菌对鲮鱼的半致死剂量。试验结果显示,这两株菌为革兰氏阴性短杆菌,兼性厌氧,有动力,能利用蔗糖、甘露糖、麦芽糖,硝酸盐还原、吲哚、MR试验均为阳性;根据其生理生化特性,鉴定为迟钝爱德华氏菌,通过PCR扩增其16SrDNA基因,经测序及NCBI比对,结果与迟钝爱德华氏菌的同源性高达99%。这两株致病菌对头孢噻肟、头孢吡肟、头孢曲松、头孢西丁、头孢哌酮、头孢呋辛等抗生素高度敏感,对链霉素、克拉霉素、红霉素中度敏感,对阿米卡星、复方新诺明、大观霉素、克林霉素不敏感。这两株菌对鲮鱼具有较强的致病力,半致死剂量分别为1.93×105cfu/g和9.65×104cfu/g。Two dominant bacterial strains （QY15814 and QY15815） were isolated from hepatopancreas, kidney and spleen of diseased mud carp （Cirrhinus molitorella） in an aquafarm in Qingyuan city, Guang- dong province. They were identified through biochemical identification tubes and 16S rDNA sequence anal- ysis, and antibiotic susceptibility test was performed through Kirby-Bauer disk diffusion method. Moreo- ver, the median lethal dose values （LD50） for the isolates to mud carp were determined. The results showed that the isolates were facultative anaerobes which were gram negative, rod in shape, and motile. Their indole, MR and nitrate reduction test were positive, and they utilized sucrose, mannose and malt- ose. The isolates were identified as Edwardsiella tarda according to their physiological and biochemical characteristics. The 16S rDNA sequences of the isolates showed a high similarity （99%） to that of E. tar- da via BLAST network services in NCBI. The isolates were highly susceptible to cefotaxime, cefepime, ceftriaxone, cefoxitin, cefoperazone, cefuroxime and the others, intermediately susceptible to phytomycin, clarithromycin, erythromycin, and not susceptible to amikacin, complex sinomin, spectinomyein, and clin- damycin. The LDs0 values for the isolates to healthy mud carps were 1.93 X 10%5 cfu/g and 9.65 X 10^4 cfu/g, respectively, indicating that they had strong pathogenicity to mud carp.

关 键 词：鲮鱼 迟钝爱德华氏菌 鉴定 药物敏感性 

分 类 号：S941.42[农业科学—水产养殖]