Abstract:A five-valent vaccine was made of Vibrio harveyi, V.anguillarum, Ewardsielatarda, V.scophtalmi and V.alginolyticus which were firstly inactivated by formalin, andthen mixed with astragalan-adjuvant. Turbot Scophthalmus maximus was subjected to vaccines via intraperitoneal injection, and the vaccines were respectively appended with(Group 2) or without astragalan-adjuvant（Group 1). Antibody titers, activities of lysozyme and superoxide dismutase were examined on the 7th, 14th, 21th, 28th, 35th, 42th, and 56th day after firstvaccination. Finally, all the fish were challenged with the five kinds of bacteria (mentioned above) on 56d. The results showed that the activities of lysozyme and superoxide dismutase of both groups reached the peak value on 28d, in which Group 2 were significantly higher than those in Group 1 (P<0.05）. The antibody titers of both groups also reached the highest on 28d, but which were much higher in Group 2 than that in Group 1 (P<0.05）. In Group 2, the antibody titers of five kinds bacteria were 27.25,26.75,28.5,28.75,26.25 respectively, and in Group 1 they were 26, 25.75, 26.75, 27.5, 25. The RPS of Group 2 was 50.0%, 50.0%, 71.4%, 62.5%, 44.4% respectively, and 37.5%, 30.0%, 42.9%, 50.0%, 33.3% in Group 1. The results suggest that the five-valent vaccine can enhance the immunity in turbot Scophthalmus maximus. In addition,the immune enhancement was markedly improved in astragalan-adjuvant group, indicating that astragalan-adjuvant has a positive effect on immunity.
