鲤鱼杀鲑气单胞菌的分离鉴定及耐药性分析

Identification and Antibiotic Resistance Analysis of Aeromonas salmonicida Isolated fromCyprinus carpio

为探究鲤鱼病原菌的生物学特性及耐药状况,从患病鲤鱼中分离到菌株CS126,对其进行形态学观察、生理生化性质测定、16SrDNA序列分析及药敏性测定。结果显示,菌株CS126为革兰氏阴性菌,不产生吲哚、不具有动力性,分解半乳糖、甘露醇,VP试验、赖氨酸脱羧酶、氧化酶阴性,七叶苷阳性。16SrDNA序列长度为1 459bp,GenBank登录号为KJ942580,与GenBank中杀鲑气单胞菌的相似性高达100%,进化树显示与杀鲑气单胞菌杀鲑亚种聚为一分支。这表明菌株CS126为杀鲑气单胞菌杀鲑亚种。该菌株对菌必治、诺氟沙星、氟苯尼考等8种药物高度敏感,但对氨苄西林、氨苄西林/舒巴坦、甲氧卞胺嘧啶和磺胺异恶唑等耐药。本试验结果为鱼类杀鲑气单胞菌的快速鉴定及鱼类疾病诊治提供参考依据。

In order to investigate the biological characteristics and drug resistance of pathogenic bacteria isolated from common carp,strain CS126 was obtained from diseased carp（Cyprinus carpio）.Its identification and drug susceptibility were studied in this experiment.The results showed that strain CS126 was gram-negative bacteria,it did not produce indoles,had no ability of mobility,decomposed galactose and mannitol,VP reaction,lysine decarboxylase and glucose oxidase was negative,esculin was positive.The results also showed that the length of 16 rDNA gene was 1 459 bp,the submission number of GenBank was KJ942580.It had 100%similarity with Aeromonas salmonicidafrom GenBank,genetic evolutionary tree displayed the isolated strain and A.salmonicida subsp.salmonicida belong to a clade.It was identified as A.salmonicidasubsp.salmonicida.This strain was highly sensitive to eight drugs,such as rocephin,norfloxacin,florfenicol,and so on,but it was resistant to ampicillin,ampicillin/sulbactam,trimethoprim and sulfafurazole.It will offer references for rapid identification of Aeromonas salmonicida and treatment of fish disease.