Abstract：
The present study describes the expression of genes in the Longissimus dorsi muscle related to meat quality of hair lambs finished in an Integration Crop-Livestock system. Twenty-eight non-castrated lambs of two breeds, Somalis Brasileira and Santa Inês, at 120 ± 15 days of age, with an average initial live weight of 18 ± 3.1 kg, were kept in a pasture-based finishing system with supplementation. Upon reaching 28 kg body weight, animals were sent for slaughter. Samples of the Longissimus dorsi and Biceps femoris muscle were harvested for analyses of gene expression and physicochemical properties. Significant differences were detected between the breeds for tissue and chemical composition, whereas the physical aspects did not differ. We observed the expression of six genes related to lipid synthesis (acetyl-CoA carboxylase [ACACA], fatty acid synthase [FAS], stearoyl-CoA desaturase [SCD], lipoprotein lipase [LPL], cell death-inducing DFFA-like effector A [CIDEA], and thyroid hormone responsive [THRSP]) and six genes related to molecular synthesis (myostatin [MSTN], growth differentiation factor 8 [GDF8], insulin-like growth factor 1 [IGF1], insulin-like growth factor 2 [IGF2], delta-like 1 homolog [DLK1], and growth hormone receptor [GHr]) in both breeds. The Santa Inês breed and the Somalis Brasileira showed similar expression patterns of genes related to lipogenesis and myogenesis of the Longissimus dorsi muscle, with the exception of the THRSP gene, in which the Somalis Brasileira have more receptors for the action of thyroid hormones, which resulted in greater thickness of fat in the carcass (subcutaneous fat) and higher lipid content in the chemical composition of the meat.
摘要：
本研究描述了与整合作物-家畜系统中完成的毛羔羊的肉质相关的背背背肌中基因的表达。二十八只两种非阉割羔羊，索马里人巴西利亚和圣塔因斯，在120±15日龄时，平均初始活重为18±3.1公斤，保持在基于牧场的整理系统中，并补充。体重达到28公斤后，动物被送去屠宰。收获背长肌和股二头肌的样品用于分析基因表达和理化性质。在组织和化学成分的品种之间检测到显着差异，而身体方面没有差异。我们观察了与脂质合成相关的六个基因的表达（乙酰辅酶A羧化酶[ACACA]，脂肪酸合成酶[FAS]，硬脂酰辅酶A去饱和酶[SCD]，脂蛋白脂酶[LPL]，诱导细胞死亡的DFFA样效应子A[CIDEA]，和甲状腺激素反应性[THRSP]）和与分子合成相关的六个基因（肌肉生长抑制素[MSTN]，生长分化因子8[GDF8]，胰岛素样生长因子1[IGF1]，胰岛素样生长因子2[IGF2]，delta样1同系物[DLK1]，和生长激素受体[GHr]）在两个品种中。SantaInäs品种和SomalisBrasileira显示出与背最长肌的脂肪生成和肌生成有关的基因的相似表达模式，除了THRSP基因,其中索马里人有更多的甲状腺激素受体，这导致car体（皮下脂肪）中脂肪的厚度更大，肉的化学成分中脂质含量更高。
