Farran M T, Thomas O P
Department of Poultry Science, University of Maryland, College Park 20742.
Poult Sci. 1990 May;69(5):757-62. doi: 10.3382/ps.0690757.
Growth studies were conducted with 3-wk-old, male broiler chicks to determine their requirements for the branched-chain amino acids (BCAA) leucine, isoleucine, and valine during the starter period. The central-composite, rotatable design was applied. The data were analyzed using regression methodology. The results showed that the linear term of Leu and the cross-product terms of Leu with Ile or Val were nonsignificant (P greater than .05). Second-order equations described the relationship between the BCAA, weight gain (WG), and feed conversion (FC). The coefficient of determination values indicated that 80% or more of the variation in WG and FC was explained by the polynomial equations. The results suggested that the Leu requirement does not exceed 1.16% of a diet calculated to contain 3,200 kcal of metabolizable energy per kilogram. The optimum response, maximum in the case of WG (444 g) and minimum for FC (1.40), would be obtained by feeding a diet containing 1.16, .80, and .90% of Leu, Ile, and Val, respectively. The values of Ile and Val are the actual values obtained when the diets were hydrolyzed for 72 hours. For Leu, however, the hydrolysis time was 24 hours.
对3周龄雄性肉仔鸡进行生长研究，以确定其在育雏期对支链氨基酸（BCAA）亮氨酸、异亮氨酸和缬氨酸的需求。采用中心复合旋转设计。使用回归方法分析数据。结果表明，亮氨酸的线性项以及亮氨酸与异亮氨酸或缬氨酸的交叉乘积项不显著（P大于0.05）。二阶方程描述了支链氨基酸、体重增加（WG）和饲料转化率（FC）之间的关系。决定系数值表明，多项式方程解释了WG和FC中80%或更多的变异。结果表明，亮氨酸需求量不超过每千克含3200千卡代谢能日粮的1.16%。通过分别饲喂含1.16%、0.80%和0.90%亮氨酸、异亮氨酸和缬氨酸的日粮，可获得最佳反应，即WG最大（444克），FC最小（1.40）。异亮氨酸和缬氨酸的值是日粮水解72小时后获得的实际值。然而，亮氨酸的水解时间为24小时。
