Effects of Several Additives on the Growth and Non-specific Immunity in Serum of Litopenaeus vannamei

WANG Duo; TIAN Xiangli; DONG Shuanglin; WANG Ling; PAN Zhe

Abstract：To investigate the effects of several additives on the growth and non-specific immunity in serum of Litopenaeus vannamei,six groups of feeds containing different types of additives were fed to Litopenaeus vannamei.The experiment was set six treatments,including control group (designated as group F) and five different feed additives (A..adding 0.6％ broken yeast to the basal diet;B..adding 0.3％ herbal extract to the basal diet;C..adding 0.3％ citric acid to the basal diet;D.adding 15mg/kg florfenicol to the basal diet;E:adding 109cfu/kg probiotics to the basal diet).The experiment was carried out for 42 days.During the experiment,10 Litopenaeus vannamei were placed in each tank (repeating 5 times each group).Results showed that the survival rates were above 90％ in all experimental groups,but the difference among groups was not significant.Compared with the control group,specific growth rate of adding broken yeast,herbal extract,citric acid and florfenicol showed significant differences(P＜0.05),but the difference among groups was not significant.Feed conversion rate of adding broken yeast,herbal extract and citric acid showed significant differences(P＜0.05),and adding broken yeast was significantly better than adding citric acid (P＜0.05).Compared with other groups,the weight gain rate and specific growth rate in A group were the highest and the feed conversion rate was the lowest.The non-specific immunity in serum suggested that,after adding bacillus to the basal diet,the SOD,ACP,AKP and LSZ were significantly higher than that of the control group(P＜0.05).Thus,adding appropriate amount of broken yeast,herbal extract,citric acid,and florfenicol to the basal diet can significantly improve the growth performance of Litopenaeus vannamei.Adding appropriate amount of five additives can improve non-specific immunity of Litopenaeus vannamei to a different extent,but adding bacillus is the best.