锦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 the pathogenic Aeromonas veronii from Brocaded crucian

作　　者：贾俊鹏 康元环[1] 张冬星[1] 陈龙[1] 孙武文 张贺亮 崔冰冰 单晓枫[1] 钱爱东[1] 

机构地区：[1]吉林农业大学动物科学技术学院,吉林长春130118 [2]长春科技学院,吉林长春130600 [3]长春市双阳区山河街道办事处畜牧兽医站,吉林长春130600

出　　处：《中国预防兽医学报》2018年第1期19-23,共5页Chinese Journal of Preventive Veterinary Medicine

基　　金：国家自然科学基金项目(31201927);吉林省科技厅重点科技攻关项目(20150204065NY);林省科技厅自然基金项目(20170101016JC)

摘　　要：为鉴定长春市某水产养殖场发病锦鲫(Brocaded crucian)病原菌,本研究从患病锦鲫体内分离得到一株优势菌株,并对其进行了常规理化特性、分子生物学、人工感染试验及药敏检测。结果显示:分离菌株为革兰氏阴性短杆菌,其理化特性与维氏气单胞菌(A.veronii)特征相符,并且其16S r DNA基因、gyr B基因、dna J基因、rpo D基因与Gen Bank中A.veronii相应基因序列的同源性均高达99%,在系统进化树中与A.veronii聚为一族,将其命名为JLND-1611;人工感染试验结果显示,锦鲫感染7 d后全部死亡,临床症状与自然病例相似,而且对斑马鱼LD_(50)为1.51×10^(2.67)cfu/m L;毒力基因检测显示,从JLND-1611可以扩增出6种毒力因子:脂肪酶(lip)、核酸酶(exu)、密度感应系统调控基因(luxs)、粘附素(aha)、气溶素(aer)及氨酸蛋白酶(ser);综合检测结果表明该分离株为致病性A.veronii。药敏试验结果显示,分离株对19种抗菌药物中头孢曲松、头孢哌酮及多西环素等药物敏感。本研究为锦鲫感染A.veronii的鉴定及治疗药物的选取提供了参考依据。To identify the pathogen from Brocaded crucian in an aquafarm in Changchun, an dominant strain was isolated from diseased Brocaded crucian. And the isolate was further identified by physiological and biochemical assay, DNA sequence analysis, artificial infection and drug susceptibility test. The results showed that the isolate was a Gram-negative bacterium, and its physiological and biochemical characteristics were consistent with Aeromonas veronii. The homology of 16S rDNA gene, gyrB gene, dnaJ gene and rpoD gene of the strain with that of A.veronii strain in GenBank was as high as 99%. The phylogenetic tree base on these gene sequences indicated the isolate clustered with A.veronii strains, and named as JLND-1611. The results of artificial infection test showed that Brocaded crucian all died after 7 days infectied with JLND-1611 and the clinical symptoms of the infected Broclded cracian were similar with that of natural infection, moreover the LD50 was 1.51×102.67 cfu/mL to zebrofish. The virulence gene detection showed that JLND-1611 could be ampilfied 6 virulence factors： lipase （lip）, nuclease （exu）,quorum sensing regulated genes （luxs）, adhesion （aha）, aerolysin （aer） and serine protease （ser）. Overall, the isolate strain was proved to be a pathogenic A.veronii. The drug sensitivity test showed that the isolate was sensitive to cefoperazone, piperacillin and doxycycline in 19 antimicrobial agents. These results provids a scientific basis for identification and treatment of A.veronii.

关 键 词：维氏气单胞菌 锦鲫 毒力因子 药敏试验 

分 类 号：S852.61[农业科学—基础兽医学]