Virulence patterns of Aeromonas eucrenophila isolated from water and infected fish

Six isolates of Aeromonas eucrenophila-2 from water and 4 from superficial skin ulcer of cat fish-were examined for haemagglutination, serum sensitivi ty, chitinase production and enterotoxicity, and correlation, if any,betwee n them; only one strain showed haemagglutination and was inhibited by both D-mannose and L-fucose, All the strains showed resistance to normal human s erum, but produced chitinase; one of them elaborated inducible chitinase. A ll these strains caused fluid accumulation only after 1-4 serial passages t hrough rabbit ileal loops, of which one strain that elaborated inducible ch itinase caused significantly more (p<0.005) fluid accumulation. These obser vations indicate that there is no correlation between enterotoxicity and ha emagglutination and/or serum resistance, and these properties did not chang e after animal passage; However, a correlation could be observed between el aboration of inducible chitinase and enterotoxin production.