Isolation of Aeromonas salmonicida from salmon lice Lepeophtheirus salmonis and marine plankton

Aeromonas sahnonicida was isolated from salmon lice Lepeophtheirus salmonis and zooplankton in samples taken at a fish farm with an outbreak of furunculosis. Approximately 104 cells of A. salmonicida per salmon louse and 600 cells of A. salmonicida per m1 of homogenized plankton suspension were detected. By use of immunomagnetic beads coated with monoclonal antibodies against the lipopolysaccharides of A. salmonicida, the bacteria were retneved in almost pure culture from certain of the heavily 'contaminated' environmental san~ples.