Ocena chorobotworczosci Aeromonas hydrophila izolowanych od ryb na terenie wojewodztwa olsztynskiego

The evaluation of potential pathogenicity of A. hydrophila strains isolated from healthy fish was carried out on the basis of their ability to produce enterotoxins, beta — haemolysins and to haemagglutinate blood cells in humans and guinea pigs. The studies comprised 29 strains of A. hydrophila isolated from 67 fish from 6 fish — breeding stations in the Olsztyn province. No correlation was found between the ability of the examined strains to agglutinate human and guinea pig erythrocytes, and the enterotoxicity and hemolitic activity. Some correlation was found between the enterotoxicity of the strains and their hemolitic activity. Incubation of A. hydrophila strains at temp. 25°C allows to detect more enterotoxic strains (31% strains) than at temp. 37°C (13% strains).