Abstract
An immunodiffusion test with heat stable antigen extracted from the kidney of infected fish is described as a method of diagnosis of BKD.
Specific precipitin bands were formed within 24 hours when the rabbit anti-serum reacted with the extract of affected parts of the kidney containing heat stable specific BKD antigen.
No precipitin bands were formed with heat extract of the kidney of healthy fish and heat extract of cells of other fish pathogenic bacteria, i. e. Aeromonas salmonicida, Vibrio anguillarum, etc. From the above findings, it was suggested that the correct diagnosis of BKD could be easily made in distant diagnostic laboratory by the sending of heat treated field specimens.
