中文摘要：

以雄性罗斯肉鸡为动物模型，探讨蛋氨酸（DLM）及其液体羟基类似物（HMTBA）对机体抗氧化能力及代谢激素水平的影响差异。结果显示，与对照以及DLM相比，饲粮添加HMTBA显著提高了肉鸡体增重、腿肌重、腿肌率、胸肌重（P〈0．05）；饲粮添加HMTBA能显著升高肉鸡血浆、肝脏以及肌肉组织的总抗氧化能力（T-AOC），提高还原型谷胱甘肽／氧化型谷胱甘肽的比率（GSH／GSSG）及增强抗氧化氢酶（CAT）活性（p〈0．05）；可显著降低全血自由基（ROS）含量和肝脏、肌肉组织中丙二醛（MDA）含量（P〈0．05）；饲粮添加0．24％的HMTBA显著增加了血浆T3、T4、FT3含量（P〈O．05）。结果表明，HTMBA较DLM更能有效地改善机体氧化还原状态，增强抗氧化能力，进而调控代谢激素，提高机体游离甲状腺激素的水平，促进肉鸡生长和肌肉沉积。

英文摘要：

In this experiment, different effects of 2-hydroxy-4-（methylthio） butanoic acid （HMTBA） and DL-methionine （DLM） on the redox state and metabolic hormone levels were determined in broilers. Compared with control, HMTBA-containing diet significantly improved body weight gain, breast weight, leg weight, and leg muscle rate（p〈0.05）. Additionally, a significant increase of T-AOC, GSH/GSSG, CAT levels in blood, muscle and liver tissue was found in HMTBA groups（p〈0.05）. And also,basal diet with HMTBA could significantly decrease the level of free radicals in whole blood and MDA in liver and muscle tissue（p〈0.05）. Furthermore, 0.24% of HMTBA supplementation led to a significantly high levels of serum T3, T4 and FT3. Compared with DLM, HMTBA-containing diet could better restore redox status,improve the antioxidation, and then regulate metabolic hormones, improve the free thyroid hormone level, accelerate muscle deposition and growth in broilers.