Isolation, identification and biological characteristics of pathogenic Aeromonas veronii.

The bacterial morphology and culture characteristics of the HX201006-1 strain isolated from the liver of diseased Cyprinus carpio var.color were observed,then the phylogenetic tree was established by biochemical analysis and 16S rDNA sequence analysis and finally the antibiotic sensitivity and pathogenicity of the HX201006-1 strain were tested.The results showed that the HX201006-1 strain was identified as Aeromonas veronii biovar sobria,the 16S rDNA sequence of the isolated strain was similar to India strain AE-21(GenBank accession number AY987724) and their homology was up to 99%.The isolated strain was of higher pathogenicity after the pathogenicity test and the white mouse and Cyprinus carpio var.color infected with 3×108 CFU/mL isolated strain would died in 16 h and 46 h respectively.The isolated strain was sensitive to 9 antibiotics such as Cefalotin,Amikacin,Gentamicin and so on,medium sensitive to Erythromycin and SMZ-TMP and different tolerance to 9 antibiotics such as Penicillin,Tetracycline,O/129 and so on.