Detection ofAeromonas salmonicidaby polymerase chain reaction in Atlantic salmon vaccinated against furunculosis

Furunculosis vaccine DNA was demonstrated by polymerase chain reaction (PCR) in head kidney and spleen cell preparations of Atlantic salmon. DNA primers transcribed from sequences of 16SrRNA were used, and the PCR products were verified by an internal, radioactively labelled 16SrDNA oligonucleotide probe. Intraperitoneally, single and double vaccinated pre-smolts were sampled 8 and 16 weeks after vaccination and found to contain vaccine DNA. Unvaccinated fish acted as negative controls. The spleen cell preparation of the double vaccinated fish were negative after 16 weeks.