黄金鲫致病性维氏气单胞菌的分离鉴定及耐药性分析

Isolation,identification and drug susceptibility of pathogenic Aeromonas veronii from Golden crucian carp

为确定吉林省黄金鲫鱼发病死亡的原因，从患病黄金鲫体内分离到致病菌JLJ-1，对该茵进行形态学观察及生理生化特性的鉴定，并对16SrDNA和管家基因gyrB、rpoD、dnaJ序列、毒力基因携带情况及耐药性进行了分析。结果表明，该菌为革兰阴性菌，结合细菌形态学特征及其生理化生化特性与维氏气单胞菌（Aerornonas veronii，A．veronii）基本相同；16srDNA与gyrB、rpoD、dnaJ序列进化比对分析显示，该病原菌与A．veronii同属一个分支，且同源性较高。将分离菌人工感染黄金鲫，7d后黄金鲫全部死亡，且临床症状与自然病例相似。通过毒力基因检测发现。JLJ-1株可扩增出6种毒力因子：气溶素（aer）、细胞毒性肠毒素（act）、黏附素（Aha）、丝氨酸蛋白酶（set）、核酸酶（exu）及脂肪酶（liP）。药敏试验显示，该菌对氟苯尼考、头咆哌酮及头炮曲松等药物比较敏感。本研究为黄金鲫感染A．veronii的鉴定及治疗药物的选取提供科学依据。

To determine death cause pathogenesis of Golden crucian carp in Jilin province, from ill- ness isolated pathogen of Golden crucian carp JLJ-1 ,the morphology of the bacteria and the identi- fication of physiological and biochemical characteristics, using 16S rDNA and butler gene gyrB and rpoD,dnaJ sequences,drug resistance and virulence gene analyses. Results showed that the bacte- ria for leather Blue＇s negative bacteria,combined bacteria form learn features and physiological of biochemical characteristics and Vickers gas single cell bacteria basic same, 16S rDNA sequence than on results showed that the bacteria and Vickers gas single cell baeteria（JX294914.1） homolo- gous sex in 99% above;based on 16S rDNA and gyrB, and rpoD,and dnaJ sequence evolution than on analysis displayed,the disease original bacteria and Vickers gas single cell bacteria with is a branch,and homologous sex high. Isolates infected Golden crucian carp, Golden crucian carp all died after 7 d, and clinical symptoms are similar to natural case. Discovered through detection of virulence genes,virulence factors of JLJ-1 can be amplified 6 ：aerosol mousse（aer）,cytotoxic enter- otoxin（act）, adhesin（Aha）, a serine protease（ser）, nuclease（exu） and lipase（lip）. Susceptibility testing showed that the bacteria on fluorine florfenicol, tou Pao head shot of ceftriaxone and cef- operazone and other drugs are more sensitive. This study of Golden crucian carp infected with Aer- omonas veronii identification and selection of treatment drugs provided a scientific basis.