l-. Azad et al. I Fish shellfish Immunology 23(2007)154-163 0 dpp 008 00 T4 Days post priming dpp/booster(dpb Fig. 1. Immune response(ELISA)of juveniles of Chanos chanos fed different vitamin( C and E)enriched diets to Vibrio vulnificus susceptibility Supra dietary levels of vitamins C and e were found to have direct influence on the immune response of juvenile milkfish as evident from the enhanced anti-FKVV antibody titres(tl, T2 and T3)in the present study Supra dietary levels of Vitamin C probably helped in neutralizing the stress responses [4, 22] of confinement in the present study and thus, resulted in enhanced antibody production. Similar enhancements in antibody production of channel catfish against Edwardsiella ictaluri [25] and in rainbow trout against V. anguillarum [4] have been reported. Working on grouper(Epinehelus awoara), Wei and co-workers [27] reported higher antibody production in the fish fed supra dietary levels of Vitamin C. Protective response of milkfish in the present study following vaccination was significant compared to the unvac cinate fish. High protective response and immunological memory in the present study can be attributed to a combi- nation of enhanced specific antibody production and probable elevation of non-specific immune responses as reported in many fish species receiving varying levels of dietary Vitamin C [23, 28-31. High specific antibody response and enhanced protective responses to bacterial challenge exhibited by milkfish juveniles is supported by the enhanced immunological memory. Similar findings were reported by Wei et al. [27] who tested higher levels of dietary Vitamin C in grouper resulting in enhanced specific antibody response against injected formalin-killed v. vulnificus and protective response against the bacterium, delivered live via injection/bath. 7222 400 4000 3000 Fig. 2. Memory factor(MF) as an index of specific immunity in vaccinated juveniles of Chanos chanos fed vitamin(C and E) enriched diets Treatment plot points with common letter-lable are not significantly(P=0.05) different from one another.susceptibility. Supra dietary levels of vitamins C and E were found to have direct influence on the immune response of juvenile milkfish as evident from the enhanced anti-FKVV antibody titres (T1, T2 and T3) in the present study. Supra dietary levels of Vitamin C probably helped in neutralizing the stress responses [4,22] of confinement in the present study and thus, resulted in enhanced antibody production. Similar enhancements in antibody production of channel catfish against Edwardsiella ictaluri [25] and in rainbow trout against V. anguillarum [4] have been reported. Working on grouper (Epinehelus awoara), Wei and co-workers [27] reported higher antibody production in the fish fed supra dietary levels of Vitamin C. Protective response of milkfish in the present study following vaccination was significant compared to the unvac￾cinated fish. High protective response and immunological memory in the present study can be attributed to a combi￾nation of enhanced specific antibody production and probable elevation of non-specific immune responses as reported in many fish species receiving varying levels of dietary Vitamin C [23,28e31]. High specific antibody response and enhanced protective responses to bacterial challenge exhibited by milkfish juveniles is supported by the enhanced immunological memory. Similar findings were reported by Wei et al. [27] who tested higher levels of dietary Vitamin C in grouper resulting in enhanced specific antibody response against injected formalin-killed V. vulnificus and protective response against the bacterium, delivered live via injection/bath. Fig. 1. Immune response (ELISA) of juveniles of Chanos chanos fed different vitamin (C and E) enriched diets to Vibrio vulnificus. Fig. 2. Memory factor (MF) as an index of specific immunity in vaccinated juveniles of Chanos chanos fed vitamin (C and E) enriched diets. Treatment plot points with common letter-lable are not significantly (P ¼ 0.05) different from one another. 160 I.S. Azad et al. / Fish & Shellfish Immunology 23 (2007) 154e163