乌江网箱养殖花鲈体表细菌分离鉴定与感染草鱼试验

Isolation, identification and infection Ctenopharyngodon idellus of body surface bacteria from cage cultured Lateolabrax japonicus in Wujiang River

利用微生物学常用的细菌分离纯化方法，从患病花鲈体表分离出了5株菌株，分别编号为Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ。进行生化试验和细菌16SrRNA基因序列测定，并将测序结果输入到NCBl（http：／／www．ncbi．nlmmih．gov／）中，利用BLAST工具对序列进行同源性对比分析。结果发现，5株细菌中，初步鉴定Ⅰ为野菊微小杆菌，Ⅱ为乙酰做小杆菌，Ⅲ～Ⅳ为巨型球菌，Ⅴ为细菌MM5。用5株细菌分别感染健康草鱼，发现5株细菌均具有致病性，其中巨型球菌对草鱼的危害较大。

By microbiology common method, 5 bacterial strains （ Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ） were isolated and purified from body surface of sicken Lateolabrax japonieus. By means of biochemical testing and 16S rRNA gene sequence determination, we proceeded sequence homology contrastive analysis by using BLAST tool in NCBI （http：//www.nebi.nlm.nih.gov/）. The identification results showed that I was Exiguobaeterium indieum, U was E. acetylieum, m-Iv were Macroeoecus easeolytieus, V was Bacterium MM5. Then we used the 5 strains to infect healthy Cteuopharyngodon idellus, the result indicated that all the 5 strains had pathogenicity, in which M. easeolytieus had more