The validity of Western blotting for the diagnosis of bacterial kidney disease based on the detection of the p57 antigen of Renibacterium salmoninarum

Six strains of Renibacterium salmoninarum were examined by Western blotting, which incorporated polyclonal and monoclonal antisera produced against the 57 kDa surface protein (=p57 antigen). An enhanced chemiluminescence (ECL) detection system increased the sensitivity of the reaction when compared to the use of chromogenic substrates. However, Western blotting was not as sensitive as culturing methods for the detection of R. salmoninarum during early stages of infection in salmonids. Yet, Western blotting was determined to be specific to R. salmoninarum, insofar as cross-reactions did not occur with Corynebacterium aquaticum or Carnobacterium piscicola.