Effects of Compound Chinese Herbal Medicines on Growth and Immunity of White Shrimp(Litopenaeus vannamei)

Trial was conducted to investigate the effects of compound Chinese herbal medicines(Milkvetch root(Radix Astragali)∶Isatis root(Radix Isatidis)∶Honeysuckle flower(Flos Lonicerae)∶gypsum=1∶1∶1∶1)on growth and immunity of white shrimp Litopenaeus vannamei,Boone,and the optimum level of the compound was also studied.Six experimental diets with different compound Chinese herbal medicines levels(0.0%,0.5%,0.9%,1.3%,1.7%,2.1%and 2.5%)were formulated.The feeding trial was carried out in 300 L cylindrical fiberglass tanks at the stocking rate of 30 shrimps(initial average weight 0.10 g)per tank for 56 days.Three replicate groups of shrimps were conducted for testing each diet.The results showed that WGR and SPR increased with the increase of compound Chinese herbal medicines levels,but only the 2.5% grade group was significantly different compared to control group(P0.05).There was no difference in the grade groups for FCR and SR.According to the analysis of variance(ANOVA)and quadratic model regression analysis of WGR and compound Chinese herbal medicines levels in the practical diets,the highest WGR was gained when compound Chinese herbal medicines level was 2.07%.The activities of SOD,PO,LSZ and AKP in the serum of white shrimps were influenced significantly.Activities of the four enzymes increased when the compound Chinese herbal medicines were lower than 2.1%,but decreased when the compound Chinese herbal medicines level was higher than that.However,the activities of ACP and POD were not significantly influenced by the level of the compound Chinese herbal medicines.Test Ⅱ The shrimps were infected vibrio by injection and feeding,death rate in 72 hours was counted.In the injection infecting experiment(1.4×108 cfu/mL,vibrio)and feeding infecting experiment(1.4×108 cfu/mL,vibrio),the immune protective rates were 50% and 79.19%.A conclusion from the trial was that adding the feed with the compound Chinese herbal medicines under laboratory conditions could promote the growth and immunity of white shrimps,and its optimum level was 2.1%.