1～14日龄北京鸭苏氨酸需要量的研究

Reasearch on the requirements of threonine for 1～14 day-old Peking ducks

试验采用2×5双因子完全随机试验设计,研究苏氨酸水平对1～14日龄北京鸭生产性能的影响,进而探讨1～14日龄北京鸭苏氨酸需要量。选取480只体重相近的1日龄健康的W系雄性北京鸭,随机分为10个处理,每个处理6个重复,每个重复8只北京鸭。试验日粮共设2个蛋白水平,分别为14%和20%;5个苏氨酸水平,分别为0.50%、0.58%、0.66%、0.74%、0.82%,各试验日粮的代谢能和其它必需氨基酸添加量一致。试验期为14d。研究结果表明:日粮蛋白质水平与苏氨酸水平产生明显的互作效应,且蛋白质水平与苏氨酸水平对1～14日龄北京鸭采食量、日增重、料重比影响均显著(P<0.01)。在高蛋白质水平下,以采食量和日增重为评价指标,分别建立其与苏氨酸需要量的回归方程,得出均呈二次曲线变化,且1～14日龄北京鸭最佳苏氨酸需要量分别为0.688%、0.737%。在低蛋白质水平下,日增重和日采食量均随着苏氨酸水平的升高而升高,未出现下降或平台期,因此,低蛋白质水平下的苏氨酸需要量高于高蛋白质水平下的苏氨酸需要量,苏氨酸需要量与蛋白质有关。

The effects of crude protein and threonine on production performance and threonine requirement of Peking ducks in 1-14 days were studied by completely randomized design.With similar pen weight,480 male Peking ducks with one-day old were allotted into 10 treatments,each included 6 replicats with 8 ducks each. Two basal diets that differed in CP （14% or 20%, respectively） were formulated to have identical contents of Thr included 5 levels（0.50%,0.58%,0.66%,0.74% and 0.82%）,energy（12.75 and 12.59 MJ/kg ME） and other essential amino acids. Basal diets were supplemented with L-Thr from 0.50% to 0.82% with 0.08% increments.Peking ducks （480） were randomly allocated to 10 dietary treatments with 6 replicates of 8 male ducks.The results showed that A significant interaction between dietary CP and Thr was found for feed intake, body weight（BW） gain and FCE. Increasing Thr and crude protein supplementation improved feed intake, BW gain and FCE.InIn the high CP levels.the effects of threonine requirements on the growth indexes of average feed intake ,average daily gain and were all quadratic.According to the conic section model,the threonine requirements were 0.688%, 0.737% ,respectively.In the low CP level,the average daily feed intake and average body weight gain increased with Thr increased, the Thr requirements was higher than in high crude protein. And the Thr requirements have some connection with crude protein levels.