50～75日龄番鸭日粮限制性氨基酸水平研究

本试验旨在研究日粮不同赖氨酸粗蛋白质比例和蛋氨酸(含硫氨基酸)赖氨酸比例对50~75日龄番鸭生产性能、血清生化指标和肌肉品质的影响。试验选用1440只健康50日龄番鸭,随机分为9组,每组4个重复,每重复40只鸭,饲喂9种不同赖氨酸粗蛋白质比例(Lys/CP)(分别为5%、5.5%、6%)和蛋氨酸(含硫氨基酸)赖氨酸比例(Me(SAA)t/Lys)(分别为35%(75%)、40%(80%)、45%(85%))的玉米-豆粕型日粮。试验结束时,进行称重,每个重复挑选2只接近平均体重的番鸭进行采血和屠宰。结果显示:①Lys/CP对日均采食量(ADFI)、日均增重(ADG)影响显著,5%和5.5%组显著高于6%组(P<0.05);Me(tSAA)/Lys为40%(80%)的组ADFI显著高于45%(85%)组,40%(80%)组ADG显著高于其他两组,而料肉比显著低于其他两组;②Lys/CP为5%的组血清尿酸和甘油三酯含量显著高于(P<0.05)其他两组;Me(SAA)t/Lys对血清尿酸和甘油三酯含量影响不显著(P>0.05);日粮Lys/CP和Me(tSAA)/Lys对血清甘油三酯含量存在交互作用;③日粮Lys/CP为5.5%的组胸肌干物质(DM)含量显著高于其他两组,粗蛋白质(CP)含量显著高于6%组;Me(tSAA)/Lys为35%(75%)和40%(80%)的组胸肌CP含量显著高于45%(85%)组;日粮Lys/CP和Me(tSAA)/Lys对胸肌DM和CP含量存在交互作用;④日粮Lys/CP为5.5%和6%的组腿肌DM含量显著高于5%组,5.5%组腿肌CP含量显著高于其他两组;Me(tSAA)/Lys为40%(80%)和45%(85%)的组腿肌DM含量显著高于35%(75%)组;日粮Lys/CP和Me(tSAA)/Lys对腿肌DM和CP含量存在交互作用。

Study on Dietary Restricted Amino Acids Level of 50-to-75-day-age Muscovy Ducks

The objective of this study was to investigate the effects of dietary lysine to crude protein ratio and methionine (sulphur amino acids) to lysine ratio on growth performance,serum biochemical parameters and meat quality of 50-to-75-day-age Muscovy ducks. 1 800 50-day-age Muscovy ducks were randomly allocated into 9 treatments containing three lysine to crude protein (Lys/CP) ratios (5%,5.5%,6%),each with three methionine(sulphur amino acids)to lysine (Met(SAA)/Lys) ratios (35%(75%),40%(80%),45%(85%)). Each treatment had four repeats with 40 ducks per repeat. At the end of this trial,weight gain,feed intake,and feed/gain of ducks from each pen were measured,and 2 ducks close to average weight selected randomly from each pen were slaughtered to collect blood and muscle samples. The results showed:①dietary Lys/CP ratio and Met(SAA)/Lys ratio had significant effect on average daily gain (ADG),average daily feed intake (ADFI) (P<0.05),5% and 5.5% were significantly higher than 6%. For ADFI,40% (80%) of Met(SAA)/Lys ratio was significantly higher than 45% (85%) of Met(SAA)/Lys ratio. For ADG,40% (80%) of Met(SAA)/Lys ratio group was significantly higher than other groups,F/G of which was significantly lower than other groups;②For serum uric acid and total cholesterol (TG),5% of Lys/CP ratio group was significantly higher than other groups. Met(SAA)/Lys ratio had no significant effect on serum uric acid and TG. There was interaction effect of Lys/CP and Met(SAA)/Lys ratio on TG;③For breast muscle DM content,5.5% Lys/CP ratio was significantly higher than other groups and for CP content was significantly higher than 6% ratio. For breast muscle CP content,35% (75%) and 40% (80%) Met(SAA)/Lys ratio were significantly higher than 45% (85%) ratio. There were interaction effects of Lys/CP and Met(SAA)/Lys ratio on breast muscle DM and CP content;④For leg muscle DM content,5.5% and 6% Lys/CP ratio groups were significantly higher than 5% group,40% (80%) and 45%(85%) Met(SAA)/Lys ratio groups were significantly higher than 35% (75%) group. For leg muscle CP content,5.5% Lys/CP ratio group was significantly higher than other groups. There were interaction effects of Lys/CP and Met(SAA)/Lys ratio on leg muscle DM and CP content.