不同基因型生长肥育猪可消化赖、蛋+胱、苏、色氨酸平衡模式研究

IDEAL AMINO ACID PATTERN FOR GROWING AND FINISHING PIGS WITH DIFFERENT GENOTYPES

试验比较研究了平均体重(33.64±1.2)kg 的大白×长白生长猪与平均体重(32.5±0.8)kg 的雅南猪可消化赖、蛋 +胱、苏、色氨酸平衡模式。按照氨基酸(AA)部分扣除氮沉积比较法 ,分别用18头大长猪和18头雅南猪进行N平衡试验。每个N平衡试验均设6个处理组 ,即高蛋白基础饲粮组(BD)、低蛋白加合成氨基酸对照组(PC)、在PC基础上轮流将所研究的4种AA扣除25 %的其它4个试验组。每个处理设3个重复 ,每个重复1头猪。饲粮为玉米—豆粕—玉米蛋白粉型。所有饲粮等能(3.40McalDE/kg) ,基础饲粮CP与可消化Lys水平相应为161g/kg、5.28g/kg。试验期大长猪日喂料120g/kgW 0.75,雅南猪日喂料100g/kgW 0.75。试验结果表明 ,按单位代谢体重的N沉积与可消化AA摄入量计算 ,大长猪AA平衡比例为 :Lys100、Met +Cys49、Thr72、Trp19 ;雅南猪为 :Lys100、Met+Cys78、Thr76、Trp21。结果显示 ,饲粮可消化氨基酸平衡模式因猪的基因型不同而异。与外种猪比较 ,雅南猪需要比较高比例的蛋 +胱、苏氨酸和色氨酸。

Two nitrogen balance trials after partial deletion of dietary amino acids(AA)were conducted to investigate the ideal balance pattern of dietary digestibile lysine(Lys),suphur-containing AA(SAA),threonine(Thr)and tryptophan(Trp)for two genotype pigs,Yorkshine × Landrace crossbred castrate(YL) with 60% lean meat in carcass and Yanan castrate(YN),a local breed with 45% lean meat in carcass.Eighteen YL with(33.64±1.2)kg of initial bodyweight and 18 YN (with (32.5±0.8)kg of initial bodyweight pigs were employed for the trials.Six isoenergetic diets based on corn,soybean meal and corn gluten meal were prepared for each trial.They were basal diet(BD) with 16% and 14.9% crude protein(CP)for each stage,25%-low-CP diet(s) supplemented with all the four AAs(control,PC)or the diet with three of the four AAs to have an equal digestible AA content,except the examined one which was 25% lower than in BD.The result showed that the ideal amino acid pattern expressed on digestible basis was Lys 100,SAA 49,Thr 72,Trp 19 for YL pigs and Lys 100,SAA 78,Thr 76,Trp 21 for YN pigs.It is concluded that pigs with different genotypes had different ideal amino acid patterns.