Antimicrobial resistance patterns of Aeromonas spp. Isolated from ornamental fish

Abstract

The potential risk of occurrence of new diseases associated with the trade of live animals is well known. However, little importance is still given to the problematic of the dissemination of resistance genes that pass along with the animal trade. In this study we aimed to isolate Aeromonas spp. strains from water and skin of ornamental fish and test their resistance to antibiotics. The samples were collected from a national ornamental fish importer, with the intent of obtaining a collection of Aeromonas strains. The identifcation of the strains was made by gyrB and rpoD gene sequencing. A total of 288 strains grouped in seven different species - Aeromonas veronii, Aeromonas media, Aeromonas jandaei, Aeromonas hydrophila, Aeromonas caviae, Aeromonas culicicola, Aeromonas aquariorum, were isolated. The susceptibility profle was determined for 28 antibiotics commonly used. All the strains presented multi-resistance to the tested antibiotics. The antibiotic susceptibility profle to tetracycline, ticarcillin, carbenicillin, ampicillin and erythromycin revealed resistance levels of more than 80%. Few strains resistant to aztreonam and imipenem were identifed. On the other hand, all were sensitive to cefotaxime and cefepime. The results show that these Aeromonas spp. strains are potentially reservoirs of antibiotic resistance genes. © 2012 Dias C, et al.