Effects of Supplementing Methionine in Fish Meal and Soybean Meal Free Diet on Growth Performance,Nitrogen Cycle and Amino Acid Deposition of Common Carp(Cyprinus carpio)and Feeding Strategy of Supplementing Crystal Amino Acid Diet
The aim of this study was to investigate the effects of supplementing methionine(Met)in fish meal and soybean meal free diet on growth performance,nitrogen cycle and amino acid deposition,as well as the effects of feeding frequency and supplementing Met on plasma amino acid contents after meal of common carp(Cyprinus carpio).A total of 540 juvenile common carp with an initial body weight of 27 g were randomly di-vided into 2 groups(groups C and M)with 9 replicates per group and 30 fish per replicate.Fish in the groups C and M were fed fish meal and soybean meal free diets with the Met(DL-Met form,purity was 98％)sup-plemental levels were 3.85 and 6.83 g/kg diet(1.14 and 1.99 g/16 g N),respectively.After the 8-week growth trail,the body weight was weighed,and the feeding frequency experiment was continued for 1 week after sampling.In the feeding frequency trial,the fish in groups C and M were randomly divided into 3 groups with feeding frequency of 1,2 and 3 times,respectively,with a total of 6 groups,and there were 3 replicates per group and 25 fish per replicate.Plasma samples were collected at different postprandial time points to deter-mine plasma free amino acid contents.The results showed as follows:1)supplementing Met in the fish meal and soybean meal free diet significantly improved the total feeding intake,specific growth rate and protein effi-ciency ratio(P＜0.05),and significantly decreased the feeding rate and feed conversion rate(P＜0.05).2)Compared with the group C,the nitrogen intake of group M was increased from 54.33 g/tank to 60.73 g/tank,but the nitrogen lose was decreased from 41.08 g/tank to 37.93 g/tank,the amino acid,total essential amino acid and total non-essential amino acid retention rates were significantly increased(P＜0.05),and the plasma urea nitrogen and total cholesterol contents were significantly decreased(P＜0.05).Supplementing Met in the fish meal and soybean meal free diet with 3 times a day feeding frequency could significantly increase the plas-ma lysine(Lys)and Met area under the curve(AUC)(P＜0.05).In conclusion,supplementing Met in the fish meal and soybean meal free diet to the requirement of common carp,the growth performance,feed effi-ciency and nitrogen retention of common carp can be significantly improved under the 3-times daily feeding mode.Increasing feeding frequency is an effective way to improve the utilization rate of crystal amino acids.[Chinese Journal of Animal Nutrition,2024,36(8):5242-5253]
common carpfish meal and soybean meal free dietmethioninefeeding frequencypostprandial kinetics
万方数据
维普
