In recent years, increased attention has been focused on breast muscle yield and meat quality in poultry production. Supplementation with nicotinamide and butyrate sodium can improve the meat quality of broilers. However, the potential molecular mechanism is not clear yet. This study was designed to investigate the effects of supplementation with a combination of nicotinamide and butyrate sodium on breast muscle transcriptome of broilers under high stocking density. A total of 300 21-d-old Cobb broilers were randomly allocated into 3 groups based on stocking density: low stocking density control group (L; 14 birds/m2), high stocking density control group (H; 18 birds/m2), and high stocking density group provided with a combination of 50 mg/kg nicotinamide and 500 mg/kg butyrate sodium (COMB; 18 birds/m2), raised to 42 days of age. The H group significantly increased cooking losses, pH decline and activity of lactate dehydrogenase in breast muscle when compared with the L group. COMB showed a significant decrease in these indices by comparison with the H group (P < 0.05). The transcriptome results showed that key genes involved in glycolysis, proteolysis and immune stress were up-regulated whereas those relating to muscle development, cell adhesion, cell matrix and collagen were down-regulated in the H group as compared to the L group. In contrast, genes related to muscle development, hyaluronic acid, mitochondrial function, and redox pathways were up-regulated while those associated with inflammatory response, acid metabolism, lipid metabolism, and glycolysis pathway were down-regulated in the COMB group when compared with the H group. The combination of nicotinamide and butyrate sodium may improve muscle quality by enhancing mitochondrial function and antioxidant capacity, inhibiting inflammatory response and glycolysis, and promoting muscle development and hyaluronic acid synthesis.

中文翻译：

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转录组分析揭示了对烟酰胺和丁酸钠对高放养密度下肉鸡肉品质的分子理解。

近年来，越来越多的注意力集中在家禽生产中的胸肌产量和肉质上。补充烟酰胺和丁酸钠可以改善肉鸡的肉质。但是，潜在的分子机制尚不清楚。本研究旨在研究在高饲养密度下补充烟酰胺和丁酸钠对肉鸡胸肌转录组的影响。根据种群密度，将300头21日龄的Cobb肉鸡随机分为3组：低种群密度对照组（L； 14只/平方米），高种群密度对照组（H； 18只/平方米）；高放养密度组则将50 mg / kg烟酰胺和500 mg / kg丁酸钠（COMB； 18只禽/ m2）混合使用，饲养至42天。与L组相比，H组显着增加了蒸煮损失，pH下降和乳腺乳酸脱氢酶活性。与H组相比，COMB显示这些指标显着降低（P <0.05）。转录组结果显示，与L组相比，H组中与糖酵解，蛋白水解和免疫应激有关的关键基因上调，而与肌肉发育，细胞粘附，细胞基质和胶原相关的那些基因下调。相比之下，COMB组与肌肉发育，透明质酸，线粒体功能和氧化还原途径相关的基因上调，而与炎症反应，酸代谢，脂质代谢和糖酵解途径相关的基因下调。 H组。