Alpha‐lipoic acid (ALA), a multifunctional antioxidant, can promote fatty acid mobilization, energy expenditure and scavenge free radicals. The effects of dietary ALA on the reproductive performance of breeder hens were investigated in the current study. In the 5‐week experiment, 180 54‐week‐old Qiling breeder hens were randomly divided into three treatments with five replicates and supplemented with three levels of ALA (0, 300 and 600 mg/kg) in the basic corn‐soya bean meal diets. 600 mg/kg ALA treatment group (HLA) significantly improved the eggshell thickness and strength (p < .05). ALA‐treated groups improved egg‐laying rate compared with the CON group, but with no statistically significant difference (p > .05). The levels of HDL‐C, ALB and estradiol (E2) of the serum in the HLA group were elevated compared with the CON group (p < .05). In addition, ALA (600 mg/kg) treatment exhibited a reduced level of serum AST and TG (p < .05). Dietary ALA increased the activity of hepatic lipase in liver (p < .05). Supplemental 600 mg/kg ALA also improved the SOD activity and total antioxidant capacity level, along with a decreased MDA in ovarian tissue (p < .05). Furthermore, the mRNA expressions of ESR1, ESR2, VTG2 and ApoB in the liver and FSHR in follicles were upregulated in the HLA group (p < .05). In conclusion, dietary supplementation with 600 mg/kg ALA during the late egg‐laying period could improve lipid metabolism and reproductive performance of breeder hens.

中文翻译：

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α-硫辛酸可提高种鸡产蛋后期的繁殖性能。

α-硫辛酸 (ALA) 是一种多功能抗氧化剂，可促进脂肪酸动员、能量消耗和清除自由基。本研究调查了日粮 ALA 对种鸡繁殖性能的影响。在为期 5 周的试验中，将 180 只 54 周龄启灵种鸡随机分为 3 个处理，5 个重复，并在基础玉米豆粕中添加 3 个水平的 ALA（0、300 和 600 mg/kg）。饮食。600 mg/kg ALA 治疗组 (HLA) 显着改善了蛋壳厚度和强度 ( p <  .05)。与 CON 组相比，ALA 治疗组产卵率提高，但差异无统计学意义（p > .05)。与 CON 组相比，HLA 组血清中 HDL-C、ALB 和雌二醇（E2）水平升高（p <  .05）。此外，ALA (600 mg/kg) 处理的血清 AST 和 TG 水平降低 ( p <  .05)。膳食 ALA 增加了肝脏中肝脂肪酶的活性 ( p <  .05)。补充 600 mg/kg ALA 还提高了 SOD 活性和总抗氧化能力水平，同时降低了卵巢组织中的 MDA ( p <  .05)。此外，HLA组肝脏ESR1、ESR2、VTG2、ApoB和卵泡FSHR mRNA表达上调（ p < .05)。总之，在产蛋后期日粮添加 600 mg/kg ALA 可以改善种鸡的脂质代谢和繁殖性能。