Effects of different feed additives and combinations on growth and non-specific immunity of European eel (Anguilla anguilla).

An experiment was conducted to investigate the effects of adding Chinese herbal medicine,enzymes preparations,cysteamine on growth performance and non-specific immune function of Anguilla anguilla.Anguilla anguilla was fed with basal diet without or with adding Chinese herbal medicine,enzymes preparations,cysteamine and their combinations(the control,Groups 1-6) for 8 weeks.The results showed that Chinese herbal medicine and cysteamine had a significant positive effect on growth and the superoxide dismutase activities(SOD) and lysozyme activities of Anguilla anguilla (P 0.05) ,enzymes preparations only increased the SOD activities(P 0.05) ;the combinations of three additives had a significant positive effect on growth and the superoxide dismutase activites(SOD) and lysozyme activities of Anguilla anguilla (P 0.05) .For Group 5,the rate of weight gain increased by 31.67%,feed conversion ratio reduced by 13.12% compared with the control group (P 0.05) .The growth rate of Group 6 was lower than that of Group 5.There was no significant difference in the feed conversion ratio,protein efficiency and immunity (lysozyme,superoxide dismutase activities) between Group 5 and Group 6(P 0.05) .However,alkaline phosphatase(AKP) activities were not affected by all tested groups(P 0.05) .Considering the cost and quantity of the additives,Group 6 was superior.