作　　者： ; ; ; ; ; ;

机构地区： 广东省农业科学院

出　　处： 《动物营养学报》 2011年第1期43-52,共10页

摘　　要： 本试验旨在研究饲粮中添加不同水平色氨酸(Trp)对1～21日龄黄羽肉鸡生产性能、体成分沉积、血清游离Trp以及下丘脑游离Trp和5-羟色胺(5-HT)含量的影响,并根据二次回归模型确定1～21日龄黄羽肉鸡适宜的总Trp和可消化Trp需要量。选用2000只1日龄岭南黄鸡,采用5×2两因子设计,设5个饲粮Trp水平(0.13%、0.16%、0.19%、0.22%和0.25%)和公母2个性别。结果表明,基础饲粮中添加Trp可显著改善黄羽肉鸡的生产性能(P<0.05),提高机体蛋白质沉积量和母鸡氮沉积率(P<0.05),增强机体脂肪和腹脂沉积(P<0.05)。基础饲粮中补充Trp可提高母鸡血清游离Trp浓度和公、母鸡下丘脑中游离Trp浓度(P<0.05),有提高公、母鸡下丘脑中5-HT浓度的趋势(P<0.10),且下丘脑5-HT浓度与平均日采食量和Trp日摄入量呈一定正相关(r=0.85,P=0.069),血清游离Trp浓度与下丘脑中游离Trp(r=0.81,P=0.094)和5-HT的浓度(r=0.81,P=0.100)具有一定正相关关系,说明饲粮中Trp可能通过下丘脑5-HT的神经递质作用来调节黄羽肉鸡的采食量。饲粮中Trp水平与性别对黄羽肉鸡血清和下丘脑中游离Trp浓度、体蛋白质沉积量的影响存在显著互作效应(P<0.05),表现为母鸡的上述各项指标对饲粮Trp浓度的变化较公鸡敏感。根据二次回归模型估测1～21日龄黄羽肉鸡获得最佳生产性能和最大体成分沉积的95%处的总色氨酸需要量,母鸡为0.200%～0.210%或0.037～0.039g/d,公鸡为0.190%～0.199%或0.036～0.038g/d;可消化色氨酸需要量,母鸡为0.179%～0.189%或0.033～0.035g/d,公鸡为0.169%～0.179%或0.032～0.034g/d。试验获得色氨酸需要量估测值因黄羽肉鸡性别、估测指标以及需要量表示方式不同而不同。 The trial was conducted to investigate the effects of dietary tryptophan （Trp） levels on growth performance, whole-body nutrient retention, serum free Trp, and the concentration of hypothalamic serotonin （5-HT） and free Trp in order to determine total and digestible Trp requirements of yellow-feathered broiler chicks aged 1 to 21 days based on quadratic regression models. Two thousand 1-day-old yellow-feathered broiler chicks were used. Five dietary treatments were compared in a 5×2 factorial arrangement with five dietary Trp levels （0.13%, 0.16%, 0.19%, 0.22% and 0.25%） and two genders. The results showed that supplementation of synthetic Trp in the basal diet increased growth performance （P0.05）, whole-body protein retention （P0.05）, whole-body fat and abdominal deposition （P0.05）, and the concentrations of hypothalamic 5-HT （P0.10） and free Trp （P0.05） of yellow-feathered broiler chicks. It also increased whole-body nitrogen retention ratio （P0.05） and serum free Trp concentration （P0.05） of female yellow-feathered broiler chicks. Hypothalamic 5-HT concentration positively correlated with average daily feed intake （ADFI） or daily Trp intake （r=0.85, P=0.069）, and serum free Trp concentration positively correlated with the concentrations of free Trp （r=0.81, P=0.094） and 5-HT in hypothalamus （r=0.81,P=0.100）, indicating that dietary Trp regulated feed intake via hypothalamic 5-HT as neurotransmitter. There were interactions between dietary Trp levels and gender in the concentrations of serum free Trp and hypothalamic free Trp and the whole-body protein retention （P0.05）. Responses of female chicks to dietary Trp levels were greater than those of male chicks. Based on 95% of the maximum growth performance and whole-body nutrients retention, the estimated total Trp and digestible Trp requirements for female birds were 0.200% to 0.210% or 0.037 to 0.039 g/d （total Trp）, and 0.179% to 0.189% or 0.033 to 0.035 g/d （digestible Trp）, and for male bir

关 键 词： 色氨酸 生产性能 体成分沉积 下丘脑 羟色胺 营养需要量 黄羽肉鸡

领　　域： [农业科学] [农业科学]