Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Ministry of Agriculture and Rural Affairs, Key Laboratory of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, China.
Key Laboratory of Animal Disease-Resistance Nutrition, Ministry of Education, Ministry of Agriculture and Rural Affairs, Key Laboratory of Sichuan Province, Animal Nutrition Institute, Sichuan Agricultural University, Chengdu, China.
Poult Sci. 2023 Jun;102(6):102545. doi: 10.1016/j.psj.2023.102545. Epub 2023 Feb 2.
This experiment was conducted to investigate the effect of theabrownins (TB) on production performance, egg quality, and ovarian function of laying hens at different ages. A total of 240 Lohmann laying hens were assigned in a 2 × 2 factorial design, which encompassed 2 layers ages (47-wk-old and 67-wk-old) and 2 dietary levels of TB (0 and 100 mg/kg) for 12 wk. Results showed that older layers had lower laying rate, egg mass, and higher feed-to-egg ratio (F/E), egg weight and unqualified egg rate than the younger layers (P < 0.01) during all the experimental period. The effect of TB was found to increase egg laying rate and feed efficiency during 5 to 8 wk, 9 to 12 wk and the overall phases and decreased unqualified egg rate during 1 to 4 wk and the overall phases (P ≤ 0.05). The eggshell quality (strength, thickness), albumen quality (albumen height and Haugh unit) of eggs from older layers were decreased during overall phases (P ≤ 0.05). TB increased eggshell strength during all phases and enhanced eggshell thickness at the end of wk 4 and 8 and increased albumen height and Haugh unit at the end of wk 8 and 12 of older layers (P ≤ 0.05). In addition, TB also increased egg quality of older layers after 14 d storage. A decrease in the serum concentration of progesterone, melatonin, follicle stimulating hormone, estradiol was observed in the older compared to the younger ones (P < 0.05), while the increase in serum concentration of progesterone, melatonin, anti-Müllerian hormone (AMH) were more emphasized when older hens received TB supplemented diet (P < 0.05). The older layer demonstrated lower the concentration of glutathione (GSH) (P < 0.05). And the activity of glutathione-s-transferase (GST) was significantly decreased in layers under 67-wk-old (P <0.05). The increase in concentration of GSH and the decrease in concentration of malondialdehyde (MDA) were more pronounced when TB were supplemented in 67-wk-old layers (P ≤ 0.05). Layers at 67-wk-old had lower mRNA expression of Heme oxygenase 1 (HO-1) (P < 0.01) in ovary. Dietary TB supplementation upregulated mRNA gene expression of HO-1, Nuclear factor E2 related factor 2 (Nrf2), Quinone oxidoreductase 1 (NQO1) (P < 0.01). Dietary TB upregulated mRNA expression of ovarian reproductive hormone receptor (estrogen receptor 1 [ESR1] and steroidogenic acute regulatory protein 1 [StAR1]]; P < 0.01). The results suggest feeding TB (100 mg/kg) could improve the egg production rate, egg quality, and antioxidant capacity of the ovary. Moreover, the effect of TB was more pronounced in older layers (64-wk-old vs. 47-wk-old).
本实验旨在研究茶褐素（TB）对不同日龄产蛋鸡生产性能、蛋品质和卵巢功能的影响。将 240 只罗曼产蛋鸡采用 2×2 因子设计，分为 2 个产蛋鸡日龄（47 周龄和 67 周龄）和 2 个 TB 日粮水平（0 和 100mg/kg），试验持续 12 周。结果表明，整个试验期间，老龄鸡的产蛋率、蛋重和料蛋比（F/E）均显著低于年轻鸡（P<0.01），蛋重和不合格蛋率也显著低于年轻鸡（P<0.01）。TB 可提高 5-8 周、9-12 周和整个阶段的产蛋率和饲料效率，降低 1-4 周和整个阶段的不合格蛋率（P≤0.05）。老龄鸡的蛋壳强度（强度、厚度）、蛋清质量（蛋清高度和哈夫单位）在整个阶段均降低（P≤0.05）。TB 可提高整个阶段的蛋壳强度，并在第 4 周和第 8 周提高蛋壳厚度，在第 8 周和第 12 周提高老龄鸡的蛋清高度和哈夫单位（P≤0.05）。此外，TB 还可提高老龄鸡 14 天贮存后的蛋品质。与年轻鸡相比，老龄鸡的血清孕激素、褪黑素、促卵泡激素、雌二醇浓度降低（P<0.05），而添加 TB 后，老龄鸡的血清孕激素、褪黑素、抗苗勒管激素（AMH）浓度升高更为明显（P<0.05）。老龄鸡的谷胱甘肽（GSH）浓度降低（P<0.05），谷胱甘肽-s-转移酶（GST）活性显著降低（P<0.05）。TB 补充可提高老龄鸡的 GSH 浓度，降低丙二醛（MDA）浓度（P≤0.05）。67 周龄鸡卵巢血红素加氧酶 1（HO-1）mRNA 表达水平显著降低（P<0.01）。TB 日粮补充可上调 HO-1、核因子 E2 相关因子 2（Nrf2）、醌氧化还原酶 1（NQO1）的 mRNA 基因表达（P<0.01）。TB 可上调卵巢生殖激素受体（雌激素受体 1[ESR1]和类固醇急性调节蛋白 1[StAR1]）的 mRNA 表达（P<0.01）。这些结果表明，饲粮添加 TB（100mg/kg）可提高产蛋率、蛋品质和卵巢抗氧化能力。而且，TB 的作用在老龄鸡（64 周龄）更为明显。
