【摘要】 本试验旨在研究日粮酪氨酸、苯丙氨酸和色氨酸供给水平和比例对泰和乌骨鸡生产性能和组织黑色素含量的影响。选用612只1日龄泰和乌骨鸡,随机分成17个处理,每个处理设3个重复,每个重复12只鸡(公母各占1/2),饲养至4周龄。采用三因素二次回归正交组合设计试验方法,建立日粮三种氨基酸水平与泰和乌骨鸡日增重和组织黑色素含量的二次回归数学模型,得出0~4周龄泰和乌骨鸡分别取得最大日增重和组织黑色素含量时日粮三种氨基酸适宜供给量和比例模式。结果表明,日粮酪氨酸、苯丙氨酸和色氨酸供给水平和比例显著影响泰和乌骨鸡日增重和胸肌、腿肌黑色素含量(P<0.01),且泰和乌骨鸡取得最大日增重和组织黑色素含量时日粮三种氨基酸最适水平和比例模式各不相同。当日粮氨基酸含量分别为酪氨酸0.79%、苯丙氨酸1.06%和色氨酸0.13%,三者比例模式为Tyr∶Phe∶Trp=85∶113∶14(相对于日粮Lys含量的比值,Lys定为100)时,可取得最大日增重5.81 g/d;而当日粮三种氨基酸含量分别为酪氨酸0.81%、苯丙氨酸1.14%和色氨酸0.13%时,胸肌黑色素含量可取得最大值3.73%,三者最佳比例模式为Tyr∶Phe∶Trp=87∶121∶14。因此,通过调节日粮酪氨酸、苯丙氨酸和色氨酸供给水平和比例可改善泰和乌骨鸡生产性能以及体内黑色素的沉积。[动物营养学报,2008,20(6):636-644][中文全文见《动物营养学报》网站(www.ChinaJAN.com)中文版2008年20卷06期]更多还原

【Abstract】 The objective of this study was to investigate the effects of dietary L-tyrosine(Tyr),L-phenylalanine(Phe),L-tryptophan(Trp) levels and ratios on the growth performance and melanin contents in tissues of Taihe silky fowls at 0~4 weeks old.Six hundred and twelve 1-day-old Taihe silky fowls were randomly allotted into 17 groups with 3 replicates in each group and 12 birds were included in each replicate(1/2 male and female respectively).When the fowls were 4 weeks old,the three-factor quadratic regressive orthogonal design was used to establish quadratic regression mathematical models for estimating the dietary Tyr,Phe and Trp contents and the daily growth rate and the melanin content in tissues of Taihe silky fowls.Then the reasonable supplement of three kinds of amino acid and its ratio mode for the silky fowls of 0~4 weeks with the greatest body weight gain and melanin content in tissues were obtained.Results showed dietary Tyr,Phe and Trp contents and ratios significantly influenced the body weight gain and the melanin content in pectoral and leg muscles of Taihe silky fowls(P<0.01).Furthermore,the optimum dietary Tyr,Phe,Trp levels and ratios for obtaining maximum body weight gain(BWG) differed from those for obtaining maximum melanin contents in tissues of Taihe silky fowls.A maximum BWG of 5.81 g/d could be obtained when the dietary Tyr,Phe and Trp levels were 0.795%,1.061% and 0.133%,respectively,with the ratio(the relative ratio of the dietary Lys content and Lys was 100) as Tyr∶Phe∶Trp=85∶113∶14.However,a maximum melanin content of 3.73% in pectoral muscle could be obtained when the dietary Tyr,Phe and Trp levels were 0.814%,1.137% and 0.133%,respectively,with the best ratio(% of Lys) as Tyr∶Phe∶Trp=87∶121∶14.It was concluded that the growth performance and melanin contents in Taihe silky fowls could be improved by controlling the dietary Tyr,Phe,Trp to the appropriate levels and ratios.更多还原