DETECTION OF AEROMONAS-SALMONICIDA, CAUSAL AGENT OF FURUNCULOSIS IN SALMONID FISH, FROM THE TANK EFFLUENT OF HATCHERY-REARED ATLANTIC SALMON SMOLTS

The fish pathogen, Aeromonas salmonicida, could be detected only by ba cteriological culture from the kidney of dead or moribund fish in one tank in a hatchery rearing Atlantic salmon (Salmo salar L.) smelts. Ho wever, by using a DNA probe specific for this species, allied to a PCR assay, the pathogen could be detected in water, feces and effluent sa mples taken from this fish tank Also, the presence of the pathogen was found in effluent samples from two fish tanks containing apparently h ealthy fish. Subsequently, the presence of pathogen in these tanks was confirmed by an increase in the daily mortality rate and by plate cul ture from moribund fish.