Immunostimulation of antibody‐producing cells and humoral antibody to fish bacterins by a biological response modifier

Abstract

Numbers of splenic antibody‐producing cells and humoral antibody titres were elevated during immunization regimes in rainbow trout when the bacterins Yersinia ruckeri or Aeromonas salmonicida O‐antigen preparations were mixed with the immunostimulator FK‐565. Fish sampled 14 days after injection showed a marked increase in the immune response when doses of 5, 10 or 100 μg of antigen were used. The immunostimulator may aid initial antigen uptake and processing.