P. OROZOVA1, V. CHIKOVA1 and H. NAJDENSKI2
1 National Diagnostic Research Institute of Veterinary Medicine, National Referent Laboratory “Diseases of Fish and Sea Mollusca”, BG - 1606 Sofia, Bulgaria
2 Bulgarian Academy of Sciences, The Stephan Angeloff Institute of Microbiology, Department Pathogenic Bacteria, BG - 1113 Sofia, Bulgaria
OROZOVA, P., V. CHIKOVA and H. NAJDENSKI, 2010. Antibiotic resistance of pathogenic for fish isolates of Aeromonas spp. Bulg. J. Agric. Sci., 16: 376-386
This study has determined and compared the antibiotic resistance towards various groups of antibiotics of 25 isolates from Aeromonas spp. with different origin. The strains have been isolated from drinking water and fish samples in Bulgaria, as well as from intensively bred trout fish in France, Sweden, Denmark, Spain, Scotland and England. The hemolytic activity of the isolates as regards sheep erythrocytes has been investigated in parallel. The Index of Resistance MAR has been calculated for each separate isolate. A wide antibiotic resistance of all clinic isolates has been determined. 60% of water isolates and 90% of clinical isolates possess a hemolytic activity. The presence in the environment of strains of Aeromonas spp. resistant to a wide group of antibiotics is a potential risk for the fishery farms. On the other hand, the results obtained give us grounds to accept the motile representatives of Aeromonas spp. as potential enteropathogens not only in our geographical region but also in Europe, as a whole.
Key words: Aeromonas spp., antibiotic resistance, MAR index, hemolysis