Department of Animal Science, National Chung Hsing University, Taichung, 402, Taiwan.
Changhua Animal Propagation Station, Livestock Research Institute, Council of Agriculture, Executive Yuan, Changhua, 521, Taiwan.
Poult Sci. 2017 May 1;96(5):1191-1203. doi: 10.3382/ps/pew350.
This study evaluated the antioxidant ability of Taisung No. 3 mulberry leaf extract (MLE) as well as the potential of mulberry leaf (ML)-based dietary supplementation for modulating the antioxidative status of laying hens. The results showed that the MLE had a total phenolic compound content of 7.4 ± 0.15 mg of gallic acid equivalent/g dry weight (DW) and a total flavonoid content of 4.4 ± 0.19 mg of quercetin equivalent/g DW. The 2, 2-diphenyl-1-picrylhydrazyl free-radical-scavenging ability was 45.9% when 0.1 mg/mL MLE was added. The lipid oxidation inhibition ability was 43.9% when 50 mg/mL MLE was added. We subjected 96 laying hens (Hendrix Genetics) to 4 treatments, namely diets supplemented with dry ML at 0 (control), 0.5, 1, or 2% for 12 weeks. Each treatment involved 8 replicates with 3 hens each. The results indicated that the 0.5% ML-supplemented group exhibited significantly higher mRNA levels of antioxidant-regulated genes, such as Nrf2, HO-1, and GST, and significantly lower ROMO1 gene expression levels at wk 12. The serum malondialdehyde level was lower and the catalase activity and superoxide dismutase activity were higher in all the ML-supplemented groups than in the control group. The egg mass and feed conversion rate significantly improved in the ML-supplemented groups compared with the control group, and, overall, 1% ML supplementation had the most favorable effects at one to 12 weeks. The egg yolk weight, shell weight, shell strength, shell thickness, yolk color, and Haugh unit were increased among all ML-supplemented groups at one to 12 weeks. On the basis of these observations, we conclude that 0.5% ML can be used as a new feed additive to potentially modulate the antioxidative status of laying hens and improve their production performance and egg quality.
本研究评估了大冢三号桑叶提取物（MLE）的抗氧化能力，以及基于桑叶（ML）的膳食补充剂对蛋鸡抗氧化状态的潜在调节作用。结果表明，MLE 总酚含量为 7.4±0.15mg 没食子酸当量/g 干重（DW），总黄酮含量为 4.4±0.19mg 槲皮素当量/g DW。当添加 0.1mg/mL MLE 时，2,2-二苯基-1-苦基肼自由基清除能力为 45.9%。当添加 50mg/mL MLE 时，其抑制脂质氧化的能力为 43.9%。我们将 96 只蛋鸡（亨德里斯遗传）分为 4 组进行处理，即添加 0（对照）、0.5、1 或 2%干 ML 的日粮，每组 8 个重复，每个重复 3 只鸡。结果表明，在第 12 周时，添加 0.5%ML 的组中，抗氧化调节基因 Nrf2、HO-1 和 GST 的 mRNA 水平显著升高，ROMO1 基因表达水平显著降低。所有 ML 补充组的血清丙二醛水平较低，过氧化氢酶活性和超氧化物歧化酶活性均高于对照组。与对照组相比，ML 补充组的蛋重和饲料转化率显著提高，总体而言，1%ML 补充在 1 至 12 周时效果最佳。在 1 至 12 周期间，所有 ML 补充组的蛋黄重量、蛋壳重量、蛋壳强度、蛋壳厚度、蛋黄颜色和哈夫单位均增加。基于这些观察结果，我们得出结论，0.5%ML 可用作新型饲料添加剂，潜在调节蛋鸡的抗氧化状态，提高其生产性能和蛋品质。
