Shan A S, Sterling K G, Pesti G M, Bakalli R I, Driver J P, Tejedor A A
Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China.
Poult Sci. 2003 Jul;82(7):1154-62. doi: 10.1093/ps/82.7.1154.
Two experiments were conducted to investigate the influence of a warm environment (35 degrees C) on the threonine and tryptophan requirements of young broiler chicks from 7 to 18 or 21 d of age. Seven hundred forty (experiment 1) and one thousand eight (experiment 2) 1-d-old Cobb x Cobb straight-run broiler chicks were raised in wire-floored battery brooders in moderate temperature rooms (33 to 34 degrees C). For the first 7 d, all chicks were fed a standard corn-soybean-meal-based crumbled starter diet. On d 7, six chicks each (experiment 1) and eight chicks each (experiment 2) were randomly assigned to individual pens. In experiment 1, chicks were fed a corn-peanut meal basal diet supplemented with six levels of threonine (0.630, 0.651, 0.673, 0.715, 0.758, or 0.800% of the diet). In experiment 2, chicks were fed a corn-corn gluten meal based basal diet supplemented with six levels of tryptophan (0.090, 0.115, 0.140, 0.165, 0.190, or 0.215% of the diet). Each dietary treatment was repeated with three pens in each room and three rooms at each temperature. Three rooms were set at a moderate temperature of 25 degrees C, and the other three rooms were set at a warmer temperature of 35 degrees C. Body weight gain, feed consumption, and feed conversion ratio were measured. The threonine requirements of young broiler chicks were 0.733 +/- 0.016% (R2 = 0.59) and 0.752 +/- 0.046% (R2 = 0.25) for body weight gain, and 0.744 +/- 0.016% (R2 = 0.67) and 0.722 +/- 0.016% (R2 = 0.47) for feed conversion ratio at 25 and 35 degrees C, respectively (broken-line linear model). The tryptophan requirements of young broiler chicks were 0.151 +/- 0.004% (R2 = 0.85) and 0.144 +/- 0.003% (R2 = 0.89) for body weight gain, 0.144 +/- 0.003% (R2 = 0.88) and 0.142 +/- 0.003% (R2 = 0.88) for feed consumption, and 0.146 +/- 0.005% (R2 = 0.76) and 0.127 +/- 0.002% (R2 = 0.94) for feed conversion ratio at 25 and 35 degrees C, respectively. On average, the threonine and tryptophan requirements of broiler chicks at 35 degrees C were very similar to those kept at 25 degrees C.
进行了两项试验，以研究温暖环境（35摄氏度）对7至18日龄或21日龄年轻肉仔鸡苏氨酸和色氨酸需求的影响。740只（试验1）和1008只（试验2）1日龄科宝×科宝直选系肉仔鸡在中等温度房间（33至34摄氏度）的金属网平养层叠式育雏器中饲养。前7天，所有雏鸡饲喂基于玉米 - 豆粕的标准破碎开食料。在第7天，试验1每组随机选取6只雏鸡、试验2每组随机选取8只雏鸡放入个体饲养栏。试验1中，雏鸡饲喂补充了六个苏氨酸水平（分别为日粮的0.63 %、0.651 %、0.673 %、0.715 %、0.758 %或0.800 %）的玉米 - 花生粕基础日粮。试验2中，雏鸡饲喂补充了六个色氨酸水平（分别为日粮的0.090 %、0.115 %、0.140 %、0.165 %、0.190 %或0.215 %）的玉米 - 玉米蛋白粉基础日粮。每个日粮处理在每个房间重复设置3个栏，每个温度设置3个房间。3个房间设置为25摄氏度的中等温度，另外3个房间设置为35摄氏度的较高温度。测定了体重增加、采食量和饲料转化率。对于体重增加，25摄氏度和35摄氏度下肉仔鸡的苏氨酸需求量分别为0.733±0.016 %（R2 = 0.59）和0.752±0.046 %（R2 = 0.25）；对于饲料转化率，25摄氏度和35摄氏度下分别为0.744±0.016 %（R2 = 0.67）和0.722±0.016 %（R2 = 0.47）（折线线性模型）。对于体重增加，25摄氏度和35摄氏度下肉仔鸡的色氨酸需求量分别为0.151±0.004 %（R2 = 0.85）和0.144±0.003 %（R2 = 0.89）；对于采食量，分别为0.144±0.003 %（R2 = 0.88）和0.142±0.003 %（R2 = 0.88）；对于饲料转化率，分别为0.146±0.005 %（R2 = 0.76）和0.127±0.002 %（R2 = 0.94）。平均而言，35摄氏度下肉仔鸡的苏氨酸和色氨酸需求量与25摄氏度下饲养的肉仔鸡非常相似。
