天然放牧条件下不同年龄的苏尼特羊肌肉常规营养成分、氨基酸组成及矿物质含量的比较

Effect of ages on the contents in conventional nutrient,amino acid and mineral of muscles of Sunite sheep under natural grazing conditions

试验研究天然放牧条件下,年龄对苏尼特羊不同部位的肌肉常规营养成分、氨基酸组成和矿物质含量的影响。试验采用单因子随机试验设计,选择天然草场放牧的体重、体型外貌接近、健康无病的8月龄、24月龄和36月龄羯羊各20只,共60只。各月龄中随机选取8只苏尼特羊,禁食12h、禁水2 h后屠宰,取背最长肌、臂三头肌、股二头肌、臀肌用于分析测定。结果显示,与24月龄和36月龄的苏尼特羊相比,8月龄组苏尼特羊的肌肉粗蛋白(CP)含量(臂三头肌除外)显著升高(P<0.05),粗脂肪(EE)含量显著降低(P<0.05),背最长肌和臀肌水分含量显著升高(P<0.05)。年龄对苏尼特羊脱脂基础的肌肉中AA平衡性由显著影响,背最长肌和臂三头肌的必需氨基酸/非必需氨基酸(EAA/N EA A)以36月龄显著升高(P<0.05),股二头肌的EAA/NEAA和必需氨基酸/总氨基酸(EAA/TAA)以8月龄显著升高(P<0.05)。年龄对苏尼特羊肌肉矿物元素含量的影响存在部位差异性,多数微量元素含量以36月龄最高(P<0.05),尤其对臂三头肌的影响更大。试验表明,年龄对苏尼特羊不同部位的肌肉常规营养成分、氨基酸组成和矿物质含量存在显著影响。

The experiment studied the effect of age on the conventional nutrient composition, amino acid composition and mineral content of different parts of Sunite sheep under natural grazing conditions. The experiment adopted a single-factor randomized trial design, and 60 Sunite sheep were selected with 20 sheep grazing in natural pastures with body weight,similar body appearance, healthy and disease-free 8-month-old, 24-month-old and 36-month-old. Eight Sunite sheep were randomly selected at each group and slaughtered after 12 h of fasting and 2 h of water deprivation, and the longissimus dorsi, triceps brachii, biceps femoris, and gluteal muscles were taken for analysis and determination. The results showed that compared with 24-month-old and 36-month-old Sunite sheep, the muscle CP content(except for the triceps brachii) of Sunite sheep in 8-month-old group was significantly higher(P<0.05), and the EE content significantly decreased(P<0.05), and the water content of the longissimus dorsi and gluteal muscles was significantly increased(P<0.05). Age has a significant influence on the balance of AA in Sunite sheep’s defatted muscles(P>0.05), and EAA/NEAA of the longissimus dorsi and triceps brachii muscles significantly increased at 36 months of age(P<0.05),EAA/NEAA and EAA/TAA of biceps femoris increased significantly at the age of 8 months(P<0.05). The influence of age on the content of mineral elements in Sunite sheep’s muscle is different. The content of most trace elements is the highest at 36 months of age(P<0.05), especially the effect on the triceps brachii. The experiment indicates that age has a significant effect on the conventional nutrient composition, amino acid composition and mineral content of the muscles of different parts of Sunite sheep.