黄颡鱼鲇爱德华氏菌的分离鉴定及其致病性研究  

Isolation,identification and pathogenicity of Edwardsiella ictaluri from Chinese yellow catfish(Pelteobagrus fulvidraco)

作　　者：徐进[1] 罗晓松[1] 曾令兵[1] 

机构地区：[1]中国水产科学研究院长江水产研究所,湖北荆州434000

出　　处：《淡水渔业》2009年第6期47-53,共7页Freshwater Fisheries

基　　金：农业部行业专项"主要淡水鱼出血病病原学与新技术疫苗研制"(200803013)

摘　　要：从患头顶溃疡症的黄颡鱼(Pelteobagrus fulvidraco)内脏组织中分离出致病力强的菌株JZ086,对该菌进行了形态学、生理生化特性的测定,并进行了Biolog全自动微生物分析系统及16S rDNA序列鉴定。结果显示:人工感染实验证实该菌为黄颡鱼的病原菌,其半数致死量(LD50)为1.7×105CFU。Biolog全自动微生物分析系统鉴定结果显示该菌为鲇爱德华氏菌(Edwardsiella ictaluri)。16S rDNA序列分析显示该菌与鲇爱德华氏菌的亲缘关系最近,同源性高达99%;系统进化树中与鲇爱德华氏菌(AB050826)自然聚为一支,二者遗传距离约为0.002。鉴定结果确认JZ086为鲇爱德华氏菌。药物敏感性试验结果显示,该菌对所测试的15种药物都敏感,其中对氨苄西林、环丙沙星、左氧氟沙星、妥布霉素等尤其敏感。Bacterial pathogen strain JZ086 was isolated from the diseased Chinese yellow catfish （Peheobagrusfulvidraco） , which suffered from a kind of disease with typical head-ulcerative symptom. Bacterial pathogen strain JZ086 was confirmed to be the causative agent of the epidemic by artificial infection test and the LD50 was about 1.7 ×10^ 5CFU. The morphological, physiological and biochemical characters of the JZ086 colonial isolate were then investigated. Biolog Automatic Microbial Identification System （ BAMIS ） and 16S rDNA molecular analysis were carried out for the identification. BAMIS results rcvealed that the strain JZ086 was Edwardsiella ictaluri. The 16S rDNA molecular analysis result showed that strain JZ086 exhibited the highest level of similarity （99%） to that of the E. ctaluri deposited in GenBank （AB050826） , and they had the same position in the molecular phylogenetic tree and the genetic distance was 0. 002. Based on the results above, bacterial isolate strain JZ086 was identified as E. ictaluri. The susceptibility test to antibiotics demonstrated that the isolate strain JZ086 was susceptible to all the selected 15 kinds of antibiotics, especially highly susceptible to ampicillin, ciprofloxacin, levofloxacin and tobramycin.

关 键 词：黄颡鱼(Pelteobagrusfulvidraco) 头顶溃疡症 病原菌 鲇爱德华氏菌(Edwardsiella ictaluri) 分离鉴定 

分 类 号：S941.42[农业科学—水产养殖]