中文摘要
日粮Tyr、Phe和Trp供给水平和比例显著影响泰和乌骨鸡日增重、日采食量、血液酪氨酸酶和苯丙氨酸羟化酶活性以及胸肌、腿肌黑色素含量（P<0.01或P<0.05），且乌骨鸡取得最大日增重（肉用）和组织黑色素含量（药用）时日粮三种氨基酸最适水平和比例模式各不相同。三种氨基酸中日粮Tyr水平是影响黑色素合成的最主要因素，其次是Phe。日粮供给较高水平的Tyr和Phe以及较低水平的Trp有利于组织黑色素的合成。在0～4周龄，当日粮氨基酸含量分别为Tyr0.79%、Phe1.06%和Trp0.13%，三者比例模式为Tyr:Phe:Trp=85:113:14（相对于日粮Lys含量的比值）时，可取得最大日增重5.81g/d；而当日粮三种氨基酸含量分别为Tyr0.81%、Phe1.14%和Trp0.13%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。在5～8周龄，当日粮Tyr、Phe和Trp水平分别0.71%、0.92%和0.14%，三者比例模式为Tyr:Phe:Trp=92:119:18时，胸肌黑色素含量可取最大值7.70%。
英文摘要
Dietary Tyr, Phe, Trp contents and their ratios significantly influenced the daily gain,feed intake,tryosinase and phenylalanine hydroxylase activities in blood, melanin content in pectoral and leg muscles of Taihe silky fowls (P<0.01). Furthermore, the optimum dietary Tyr, Phe, Trp levels and their ratios for obtaining maximum BWG differed from those for obtaining maximum melanin contents in tissues of Taihe silky fowls. Tyr was the first factor influenced the melanin biosynthesis in tissues, followed by Phe at whole growth stage. Higher dietary levels of Tyr and Phe and lower level of Trp should be provided for maximum deposition of melanin in Taihe silky fowls. At 0-4 weeks of age, a maximum BWG of 5.81g/d can be obtained when the dietary Tyr, Phe and Trp levels was 0.79%, 1.06% and 0.13%, respectively, with the ratios (% of Lys) as Tyr:Phe:Trp=85:113:14. However, a maximum melanin content of 3.73% in pectoral muscle can be obtained when the dietary Tyr, Phe and Trp levels was 0.81%, 1.14% and 0.13%, respectively, with the ratios (% of Lys) as Tyr:Phe:Trp=87:121:14. At 5-8 weeks of age, a maximum melanin content of 7.70% in pectoral muscle can be obtained when the dietary Tyr, Phe and Trp levels was 0.71%, 0.92% and 0.14%, respectively, with the ratios (% of Lys) as Tyr:Phe:Trp=92:119:18.
结题摘要
日粮Tyr、Phe和Trp供给水平和比例显著影响泰和乌骨鸡日增重、日采食量、血液酪氨酸酶和苯丙氨酸羟化酶活性以及胸肌、腿肌黑色素含量（P<0.01或P<0.05），且乌骨鸡取得最大日增重（肉用）和组织黑色素含量（药用）时日粮三种氨基酸最适水平和比例模式各不相同。三种氨基酸中日粮Tyr水平是影响黑色素合成的最主要因素，其次是Phe。日粮供给较高水平的Tyr和Phe以及较低水平的Trp有利于组织黑色素的合成。在0～4周龄，当日粮氨基酸含量分别为Tyr0.79%、Phe1.06%和Trp0.13%，三者比例模式为Tyr:Phe:Trp=85:113:14（相对于日粮Lys含量的比值）时，可取得最大日增重5.81g/d；而当日粮三种氨基酸含量分别为Tyr0.81%、Phe1.14%和Trp0.13%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。在5～8周龄，当日粮Tyr、Phe和Trp水平分别0.71%、0.92%和0.14%，三者比例模式为Tyr:Phe:Trp=92:119:18时，胸肌黑色素含量可取最大值7.70%。