Resistance characterization, virulence factors, and ERIC-PCR fingerprinting of Aeromonas veronii strains isolated from diseased Trionyx sinensis.

Aeromonas veronii (AV) is an important pathogen causing severe diseases in aquaculture. Fifteen A. veronii strains isolated from diseased Trionyx sinensis from four aquafarms was characterized by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), antibiotic susceptibility testing, and identification of virulence factors. A. veronii strains were grouped into nine ERIC types with discriminatory ability (D) of 91.43 based on 90% similarity. The virulence genes were detected for 73% (aer), 80% (ast), 13% (alt), and 40% (act) of the strains, respectively, and five antibiotic resistance patterns with D of 0.829 were observed by antibiotic susceptibility testing. Furthermore, some AV isolates (AV1, AV2, AV3, and AV4) show the same characterization (the same ERIC types, presence of virulence genes in genomes, and antibiotics resistance).