自然放牧与放牧补饲育肥对肉羊血浆和肌肉中氨基酸组成的影响

Effects of Natural Grazing and Grazing with Supplementary Feeding on Amino Acid Composition of Plasma and Muscle of Mutton Sheep

本试验研究了呼伦贝尔羊(HL)和呼伦贝尔羊与杜泊羊杂交1代(HZ)羔羊在自然放牧(NG)与放牧补饲(GS)2种不同育肥方式下,其血浆和肌肉组织(背最长肌、臂三头肌、股二头肌)中氨基酸(AA)组成的变化。采用2×2完全随机试验设计,选择体重、体况接近的健康4月龄断奶HL和HZ公羔各60只。因素1为育肥方式,分为NG与GS;因素2为品种,分为HL与HZ。共分为4组,每组30只。进行为期60 d的育肥。结果表明:1)NG组血浆中必需氨基酸(EAA)、限制性氨基酸(LAA)、功能性氨基酸(FAA)和总氨基酸(TAA)含量显著低于GS组(P<0.05),呈味氨基酸(DAA)含量有低于GS组趋势(0.05≤P<0.10)。2)与GS组相比,NG组背最长肌中粗蛋白质(CP)、LAA含量显著升高(P<0.05)。3)与GS组相比,NG组臂三头肌中LAA和DAA含量显著降低(P<0.05),EAA含量均有降低的趋势(0.05≤P<0.10)。4)NG组股二头肌中CP、EAA、NEAA、TAA、LAA、BCAA、DAA含量显著低于GS组(P<0.05)。5)与HL组相比,HZ组血浆EAA,背最长肌LAA,臂三头肌BCAA和股二头肌EAA含量显著(P<0.05)或有显著趋势升高(P<0.10)。由此可见,GS羔羊肉蛋白质营养价值优于NG,HZ羔羊肉蛋白质营养价值优于HL羔羊。

This experiment was conducted to investigate the changes of amino acid（ AA） composition of plasma and muscle tissues（ longissimus,arm triceps and biceps femoris） of Hulunbeier lambs（ HL） and the hybrid（ HZ） betw een HL and Dorper sheep under tw o fattening modes of natural grazing（ NG） and grazing with supplementary feeding（ GS）. The experiment adopted a 2 × 2 factorial arrangement. Sixty healthy weaned HL and sixty HZ with similar body weight and body condition were selected. Factor 1 was fattening modes（ NG vs. GS）,and factor 2 was species（ HL vs. HZ）. Lambs were divided into 4 groups of 30 animals each. The results show ed as follow s： 1） plasma contents of essential amino acid（ EAA）,limited AA（ LAA）,functional AA（ FAA） and total AA（ TAA） of NG group were significantly low er than those of GS group（ P〈0.05）,delicious AA（ DAA） content tended to be low er than of GS group（ 0.05≤P〈0.10）. 2） Compared with GS group,the contents of CP and LAA of longissimus of NG group were significantly higher（ P〈0.05）. 3） Compared with GS group,the contents of LAA and DAA of arm triceps of NG group were significantly low er（ P0.05）,EAA content of NG group tended to be low er（ 0. 05 ≤ P〈0. 10）. 4） Compared with GS group,the contents of CP,EAA,non-essential AA（ NEAA）,TAA,LAA,branched-chain AA（ BCAA） and DAA of biceps femoris of NG group were significantly low er（ P〈0.05）. 5） Compared with HL group,plasma EAA,longissimus LAA,arm triceps BCAA and biceps femoris EAA contents were significantly（ P〈0.05） or tended to be significantly increased（ P〈0.10）. It is concluded that muscle protein nutrition value of GS is better than NG,and protein nutrition value of HZ is better than HL.