Effects Of Several Feed Additives On Digestive Enzyme And Correlative Immune Factors Of Macrobrachium Nipponense

Oriental fiver prawn systematic named Macrobrachium nipponense is one of the most important freshwater cultivation crustaceans in our country.However,along with the rapid development of aquaculture industry,the degree of intensive farming of high-density increased,large-scale use of artificial feed,some deep level problems were exposed which restricted the healthy development of the cultivation industry.Focus on solving the aquatic products safety and reducing water pollution problems,the study of eco-friendly aquatic feed has become a hot area.The development and application of related feed additive has also been urgent increasingly.On the basis of research on the fishery feedstuff around the world,the effects of Macrobrachium nipponense on the weight gain rate,the activities of amylase,tryptase and pepsin in the stomach and the hepatopancreas,intestine protease,as well as the activities of acid phosphatase(ACP),alkaline phosphatase(ALP),superoxide dismutase(SOD) and phenol oxidase(PO) in the muscle tissue,the hepatopancreas and the serum were studied. The effects of several kinds of feed additive on the growth,digestion enzymes,immunity related factors and survival rate of Macrobrachium nipponense were discussed.Then,the feed additive which were effective on promoting growth and preventing disease were picked out.1 Effects of Several Kinds of Feed Additive on Digestive Enzyme Activities and Growth of Macrobrachium nipponenseFour kinds of feed additive,which were Chinese herbal medicineⅠ,Chinese herbal medicineⅡ,synbiotics and compound enzymes,were maxed with basal feedstuff separately. The added levels of them were 15 g·kg^-1,20 g·kg^-1,0.2 g·kg^-1 and 0.6 g·kg^-1 respectively.The experimental Macrobrachium nipponense individuals were cultured in concrete tank for 40d feeded with the trial feedstuffs.Then,the activities of amylase,tryptase and pepsin in the stomach and the hepatopancreas,as well as the activity of intestine protease,and the relative weight gain rate were investigated.One-way ANOVA shown that feed additives had significant effects on the activities of digestive enzymes in the stomach and the hepatopancreas(pepsin,tryptase) and on the relative weight gain rate(P＜0.05).However, no significant differences were found in activities of the intestine protease,as well as the hepatopancreas amylase,among different experimental groups(P＞0.05).Only amylase activity in stomach of Chinese herbal medicineⅠwas significantly higher than the activities of other groups.The experiment shown that the relative weight gain rate and most of the digestive enzymes activity items of control group were significantly lower than that ones of other groups respectively,except pepsin in stomach of compound enzymes group,as well as tryptase and amylase in stomach of Chinese herbal medicineⅡgroup.The protease of intestine may have some positive correlation with the relative weight gain rate.The relative weight gain rates of Chinese herbal medicineⅠ,Chinese herbal medicineⅡ,compound enzymes and synbiotics group were higher than that one of control group by 13.10%, 16.53%,22.07%and 32.22%respectively.So it was concluded that the feedstuffes of the four groups can be digested and absorbed more efficiently than the feedstuff of control group.2 Effects of Several Kinds of Feed Additive on immune related factors and survival rate of Macrobrachium nipponenseFour kinds of feed additive,which were,Chinese herbal medicineⅠ,Chinese herbal medicineⅡ,synbiotics and compound enzymes,were maxed with basal feedstuff separately to form trial group feedstuffs.The added levels of them were 15 g·kg^-1,20 g·kg^-1,0.2 g.kg^-1 and 0.6 g·kg^-1 respectively.The experimental Macrobrachium nipponense individuals were cultured in concrete tank for 40d feeded with the trial feedstuffs.Then,the activities of acid phosphatase(ACP),Alkaline phosphatase(ALP),superoxide dismutase(SOD) and phenol oxidase(PO) in the muscle tissue,the hepatopancreas and the serum were investigated.The results shown that ACP activities in the hepatopancreas were higher than the activities in the muscle tissue,ACP activities of compound enzymes group was the highest,it was significantly higher than control group and synbiotics group;ALP activities in the hepatopancreas were higher than the activities in the muscle tissue,Chinese herbal medicineⅡgroup was the highest,it was significantly higher than control group and compound enzymes group.SOD activities in the hepatopancreas were higher than the activities in the muscle tissue,but no significant differences were found.No significant differences were found among PO activities in the hepatopancreas,but significant differences were found in the muscle tissue,synbiotics group was significantly higher than other groups,in the serum,ACP activity of compound enzymes was significantly higher than the activities of other groups,ALP activity of compound enzymes was significantly higher than the activities of other groups,PO activity of Chinese herbal medicineⅡwas the highest.Survive rate of Chinese herbal medicineⅡwas significantly higher than control group.It was concluded that,feedstuff maxed with Chinese herbal medicineⅠ,Chinese herbal medicineⅡor synbiotics were more effective than feedstuff maxed with control group in disease prevention and immunity.Through suitable addition of one kind of microbial preparation synbiotics,a complex enzyme preparation and two kinds of Chinese herbal medicine preparation,the effects of Macrobrachium nipponense on the digestive enzymes,immune related factors,weight gain rate and survival rate were studied.The results enriched Macrobrachiurn nipponense nutriology material,provided the basal data to produce high quality artificial feed,and pointed out the feasible way and method for Macrobrachium nipponense healthy cultivation.