JOINT STUDY ON FAT DECREASE OF BROILERS IN THE TROPICS

在7日龄时，将所有雏鸡分为如下5组：自由采食、75%自由采食、65%自由采食、55%自由采食和45%自由采食。对照组采用限制性饲养，试验期为10 d（7 d. 17 D。2）早期限饲后，再投喂后，补偿生长并不立即发生。49日龄以前，限制饲养雏鸡的体重与自由饲养雏鸡的体重不相等。3）56日龄时，限制组雏鸡的体重显著高于对照组; 4）限制组雏鸡的饲料利用率显著高于对照组限制雌鸡的腹脂重和胴体脂肪含量低于对照组，55%或45%自由采食。6）对于两种性别，自由采食鸡的死亡率和畸形率均高于限制采食鸡。19971）饲喂低蛋白质日粮可降低饲料成本并提高蛋白质效率，然而，试验结果表明：（1）日粮蛋白质水平越低，肉仔鸡体脂含量越高;（2）日粮蛋白质水平越低，日粮中添加蛋氨酸和半胱氨酸对肉仔鸡生长性能和脂肪代谢的影响（0-21天）和生长者（3）试验前期饲喂低蛋白日粮（CP 17%），日粮中添加0.54%Met + Cys（0-21天）导致体重增加改善，6周龄时肌肉的脂肪积累和甘油三酯含量减少。

19961) At 7 days of age, all chicks were divided into 5 groups as follows : fed ad libitum, fed 75% ad libitum, fed 65% ad libitum, fed 55% ad libitum, and fed 45% ad libitum. Chicks were fed restrictiviely for 10 days (7 d. through 17 d. ) of a 56-day trial.2) When chicks were feed-restricted at early age, compensatory growth did not immediately occur in following refeeding. Body weights of restricted chicks were not equal to the ad libitum chicks before 49 days of age.3) At 56 days of age, body weights of restricted chicks were heavier than that of the control.4) Feed efficiency of restricted chicks were better than that of the control.5) Abdominal fat weights and carcass fat contents of restricted female chicks were lower than those of the control when female chicks were fed either 55% or 45% ad libitum.6) Mortality and abnormality were higher in ad libitum chicks than restricted chicks for both sexes.19971) Feeding a low protein diet results in a reduction in the feed cost and improved protein efficiency ratio, however, body fat contents in Broilers increased as the dietary protein level decreased.2) The experiment were conducted to determine the effect of a low-protein diet supplemented Met + Cys on the growth performance and fat accumlation of female broilers during the starter (0-21 days) and grower (22-42 days) periods.3) Feeding the low-protein diet (CP 17%) supplemented 0.54% Met + Cys during starter period (0-21 days) resulted in improved body weight gain, a decrease in fat accumulation and triglyceride contents of muscles at 6 weeks of age.