Bk. Gudmundsdottir et al., SURVIVAL AND HUMORAL ANTIBODY-RESPONSE OF ATLANTIC SALMON, SALMO-SALAR L., VACCINATED AGAINST AEROMONAS-SALMONICIDA SSP. ACHROMOGENES, Journal of fish diseases, 20(5), 1997, pp. 351-360
Atlantic salmon were vaccinated against Aeromonas salmonicida ssp. ach
romogenes(Asa) by injection with three vaccines developed in our labor
atory and an autogenous bacterin (IcelandBiojec.OO, IBOO) produced by
a commercial vaccine producer. The humoral antibody responses to bacte
rial antigens were monitored by ELISA and Western blotting. The fish w
ere challenged by infection with Asa 6 and 12 weeks post-vaccination,
Protection was induced in all groups of vaccinated fish. The protectio
n achieved was time-dependent. The autogenous bacterin, IBOO, induced
a protective immune response later than our experimental vaccines. All
the vaccines tested induced specific antibody response that increased
between 6 and 12 weeks after vaccination. The antibody response was m
ainly directed against the A-layer protein, but antibodies to other ba
cterial components were also detected. Significant correlation was obt
ained between the antibody titre to extracellular Asa antigens, induce
d by the different vaccine preparations, and survival of vaccinated fi
sh challenged by a virulent Asa strain. Furthermore, the detection of
antibodies directed against an extracellular toxic metallo-caseinase,
AsaP1, in fish sera correlated with protection.