Isolation, identification and phylogenetic analysis of pathogenic bacteria in Ictalurus punctatu
斑点叉尾鮰病原细菌的分离鉴定及系统发育分析

Sixteen strains of suspicious pathogenic bacteria were isolated from the branchias, intestines and livers of Ictalurus Punctatus with the tranditional microbiology method. Used the isolated genome DNA as the templet, about 600bp fragments of 16S rDNA of sixteen strains were amplified by PCR methold. The sequences analysis indicated that the similarity value of nine strains of the sixteen bacteria are 98%~100%, five are 95%~97% and two are 92%, by comparing the 16S rDNA sequences of the isolated strains with the relative bacteria species in the GenBank database. The phylogenetic analysis showed that the sixteen strains of bacteria obviously assembled three branches.