Research Of The Optimum Protein Level In Feed And The Environmental Protection Additives Of Macrobrachium Nipponense

This experiment which refered to the some overseas and domestic study on environmental protection feeds of aquaculture is about the research of environmental protection feeds of Macrobrachium nipponense.Macrobrachium nipponense were provided the formulated the same energy but contain different levels of protein and the optimum protein level in the diet was confirmed by the production performance.By adding different feed additives (Flavomycin,Chinese herb medicine, Synbiotics, Compound enzyme) in the diet the experiment is to investigate addivives' influence on performance,which included the index of production performance (Survival rate,Weight gain rate) ,the activities of digestive enzyme and the index of immune enzyme (ACP,AKP,SOD,PO) in serum,and to select the environmental protection feed additive having the good effects.The purpose of this experiment is to provide more theoretical evidence in aquaculture for the research of feeds too.EXPERIMENT 1The effects of dietary protein levels on the digestive enzyme activities and growth of Macrobrachium nipponenseThe effects of dietary protein levels on the digestive enzyme activities and growth of Macrobrachium nipponense (mean initial weight,0.28±0.07g) were studied. The diets were formulated the same energy but contain five levels of protein (28%,32%,36%,40%,44%).The 52-day feeding experiment showed that the dietary protein levels had significant effects on the weight gain rate ,feed conversion ratio and the protease activity in the hepatopancreas(P＜0.05).Those fed the diet containing 40% protein showed the highest weight gain rate and the lowest feed conversion ratio among all the dietary protein levels.The protease activity in the hepatopancreas increased with the increase in dietary protein levels,but the activity of pepsin decreased as the dietary protein level was above 36% and the activity of trypsin-like enzyme decreased as the dietary protein level was above 40%.The protease activity in the stomach had the same increasing trends with the increase in dietary protein levels,but the dietary protein levels had no significant effects on the protease activity in the stomach(P＞0.05).Regarding weight gain rate as index,using the method of linear regressive to get the equation y＝0.3548x+46.338 and using the method of parabola regressive to get the equation y=-0.0771x²+5.9691x-53.42,the protein requirement of Macrobrachium nipponense was estimated to be 38.7～40.3%.Based on the results such as the weight gain rate,feed conversion ratio and digestive enzyme activities,it was reasonable to recommend 38.7～40.3% as the optimum protein level in the diet for sub-adult Macrobrachium nipponense.EXPERIMENT 2The effects of dietary protein levels on the immune enzyme activities and survival rate of Macrobrachium nipponenseThe effects of dietary protein levels on the survival rate and immune enzyme activities of Macrobrachium nipponense (mean initial weight,0.28±0.07g) were studied.The diets were formulated the same energy but contain five levels of protein (28%,32%,36%,40%,44%).The 52-day feeding experiment showed that the dietary protein levels had significant effects on the survival rate(P＜0.05).Those fed the diet containing 40% protein showed the highest survival rate among all the dietary protein levels.The dietary protein levels had significant effects on the activity of ACP in the hepatopancreas (P＜0.05) and had not significant effects on the activities of AKP and SOD in the hepatopancreas(P＞0.05).EXPERIMENT 3The effects of the environmental protection feed additives on digestive enzyme activities and growth ofMacrobrachium nipponenseMacrobrachium nipponense (mean initial weight, 0.60±0.11g) were divided randomly into 5 groups in experiment in terms of the feed provided.Groupâ… was the control fed with basic diet added 0.08 g.kg^-1 Flavomycin ,whereas Groupâ…¡,â…¢,â…£andâ…¤were fed with basic diet added 15 g.kg^-1 Chinese herb medicineâ… ,20g.kg^-1 Chinese herb medicineâ…¡, 0.2 g.kg^-1 Synbiotics, 0.6 g.kg^-1 Compound enzyme respectively. The 40-day feeding experiment the weight gain rate and the activities of digestive enzymes were determined.The results showed that the different additives in diet had significant effects on the weight gain rate,stomach and hepatopancreas' activities of digestive enzymes(P＜0.05),but had no significant effects on the activities of erepsin(P＞0.05).Compared with the Groupâ… the others digestive enzyme activities were all higher excepting the trypsin- like enzyme activity in stomach for Groupâ…¢and the pepsin activity in stomach for Groupâ…£were lower.The trypsin- like enzyme activity for Groupâ…£andâ…¤in stomach,the pepsin activity for Groupâ…¤in stomach,the pepsin activity and trypsin- like enzyme activity for Groupâ…¢andâ…£in hepatopancreas and the trypsin-like enzyme activity for Groupâ…¤in hepatopancreas were significantly higher(P＜0.05).The weight gain rate for Groupâ…¡,â…¢,â…£andâ…¤were higher 13.10%,16.53%,32.22% and 22.07% respectively and the weight gain rate for Groupâ…£andâ…¤were significantly higher(P＜0.05).From results we supposed that there might be some relationship between the activities of erepsin and the weight gain rate.In conclusion, compared with Flavomycin, as feed additives Chinese herb medicine, Synbiotics and Compound enzyme had the effects on increasing the growth of Macrobrachium nipponense and Synbiotics had the good effects on increasing growth of Macrobrachium nipponense in the experiment.EXPERIMENT 4The effects of the environmental protection feed additives on immune enzyme activities and survival rate of Macrobrachium nipponenseMacrobrachium nipponense (mean initial weight, 0.60±0.11g) were divided randomly into 5 groups in experiment in terms of the feed provided. Groupâ… was the control fed with basic diet added 0.08g.kg^-1 Flavomycin,whereas Groupâ…¡,â…¢,â…£andâ…¤were fed with basic diet added 15g.kg^-1 Chinese herb medicineâ… ,20g.kg^-1 Chinese herb medicineâ…¡,0.2g.kg^-1 Synbiotics, 0.6 g.kg^-1 Compound enzyme respectively. The 40-day feeding experiment the survival rate and the activities of immune enzymes were determined.The results showed that the different additives in diet had significant effects on the the activities of immune enzymes in serum (P＜0.05),but had no significant effects on the survival rate(P＞0.05).Compared with the Group I the survival rate for Groupâ…¡,â…¢,â…£andâ…¤were higher 9.82%,13.14%,6.65% and 0.03% respectively, the others immune enzyme activities were all higher excepting the PO activity in serum for Groupâ…¤was significantly lower than Groupâ… (P＜0.05).The ACP activity for Groupâ…¢andâ…¤,the AKP activity for Groupâ…¡,â…¢andâ…¤, the SOD activity for Groupâ…¡,â…¢,â…£andâ…¤and the PO activity for Groupâ…¡andâ…¢were significantly higher(P＜0.05).In conclusion,compared with Flavomycin,as feed additives Chinese herb medicine and Synbiotics had the effects on increasing the survival rate and immune ability of Macrobrachium nipponense and Compound enzyme had no effects on increasing the survival rate of Macrobrachium nipponense.