VACCINATION OF JUVENILE TIGER GROUPER WITH THREE INACTIVATED BACTERIAL PATHOGENS

An experiment to evaluate the efficacy of inactivated polyvalent bacterial vaccines to increase specific immunity of tiger grouper ( Epinephelus fuscoguttatus ) against bacterial infection was conducted in floating net cages located in Sumbawa Island, West Nusa Tenggara. Polyvalent bacterial vaccine was prepared by mixing three species of killed-bacteria ( Vibrio harveyi , V. alginolyticus , and Photobacterium leiognathi ) with ratio of 1:1:1.The density of bacterial vaccine was adjusted at 10 10 CFU/ml. The vaccines were delivered by immersion. The control fish were immersed in sea water without vaccine. Fish with ± 6 cm of total l ength and ± 7 g of body weigth were used in this experiment. The fishes were reared in concrete tanks in hatchery of Gondol, Bali until they reached ± 9 cm of total length. Later, t he fish es were reared for 6 months in floating net cages located in Sumbawa. Re-vaccinations were delivered 60 days and 120 days post initial vaccination. The results showed that titer antibody and survival rate of the vaccinated fish were 1/128 and 77.11%, higherth a n the control (titer antibody = 1/4-1/8 , survival = 45 . 56%, respectively ). The relative percent survival of the vaccinated fish was 57.95%. It was suggested that the vaccines were immunogenic and had protective ability against bacterial infection in tiger groupers.  Keywords: bacterial disease, polyvalent bacterial vaccine, tiger grouper