EN
The studies were carried out on 67 fish coming from six breeding stations. It was found that the fish were a potential reservoir of A. hydrophila and therefore might be a source of infections and alimentary poisonings in humans. From the surface of fish there were isolated 17 strains of A. hydrophila (25.3%), from the homogenates of internal organs — 10 strains (14.9%) and from muscles — 2 strains (2.9%). All the examined strains were susceptible to streptomycin, neomycin, gentamycin, chloramphenicol and nalidixic acid. They were resistant to penicillin, ampicillin and tylosin. As to other antibiotics: 83% strains were susceptible to oxytetracycline, 25% to sulphonamides, 55% to trimethoprin plus sulphametozazol and 25% to nitrofurantoin.