Maciej J, Schäff C T, Kanitz E, Tuchscherer A, Bruckmaier R M, Wolffram S, Hammon H M
Institute of Nutritional Physiology "Oskar Kellner,", Leibniz Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany.
Institute of Behavioural Physiology, Leibniz Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany.
J Dairy Sci. 2016 Jan;99(1):805-11. doi: 10.3168/jds.2015-9906. Epub 2015 Nov 18.
Scientific proof for flavonoids as a health tool in calf nutrition is inconsistent. We investigated the effects of the most abundant flavonoid, quercetin, and of a green tea extract (GTE) containing various catechins on the metabolic and antioxidative traits in dairy calves to clarify their potential health-promoting effects. Male newborn German Holstein calves (n=7 per group) received either no flavonoid (control group), 10mg of quercetin equivalents as quercetin aglycone or as rutin/kg of body weight (BW) per day, or 10mg/kg of BW per day of a GTE from d 2 to 26 of life. The supplements were provided with the morning and evening feeding. The calves were fed colostrum and milk replacer, and BW, feed intake, and health status were evaluated daily. Blood samples were collected from a jugular vein on d 1, 5, 12, 19, and 26 before the morning feeding to investigate the metabolic and antioxidative status of the calves. The growth performance and health status remained unchanged, but the GTE-fed calves had fewer loose feces than the controls. The plasma concentrations of quercetin changed over time and were higher in the rutin-fed group than in the control group, whereas the catechins were below the detection limit. The plasma Trolox equivalent antioxidative capacity and ferric reducing ability of plasma were measured as markers for plasma antioxidative capacity. The concentrations of Trolox equivalent antioxidative capacity increased, whereas ferric reducing ability of plasma decreased after the first day of life in all the groups. The oxidative stress markers in the plasma were measured as thiobarbituric acid reactive substances and F2-isoprostanes, but these did not indicate treatment or time effects. The plasma concentrations of total protein, albumin, urea, lactate, glucose, and nonesterified fatty acids and of insulin and cortisol varied over time, but no group differences were caused by the flavonoid supplementation. In summary, orally administered quercetin and catechins at the dosages used in the present study resulted in weak effects on health and no effects on the metabolic and antioxidative status of newborn dairy calves.
黄酮类化合物作为犊牛营养中的一种健康工具的科学证据并不一致。我们研究了最丰富的黄酮类化合物槲皮素以及含有多种儿茶素的绿茶提取物（GTE）对奶牛犊牛代谢和抗氧化特性的影响，以阐明它们潜在的健康促进作用。雄性新生德国荷斯坦犊牛（每组n = 7）从出生后第2天到第26天，要么不接受黄酮类化合物（对照组），要么每天接受10毫克槲皮素当量的槲皮素苷元或芦丁/千克体重（BW），要么每天接受10毫克/千克BW的GTE。这些补充剂在早晚喂食时提供。犊牛喂食初乳和代乳品，每天评估体重（BW）、采食量和健康状况。在出生后第1、5、12、19和26天早晨喂食前，从颈静脉采集血样，以研究犊牛的代谢和抗氧化状态。生长性能和健康状况保持不变，但喂食GTE的犊牛腹泻比对照组少。槲皮素的血浆浓度随时间变化，芦丁喂养组高于对照组，而儿茶素低于检测限。测量血浆Trolox等效抗氧化能力和血浆铁还原能力作为血浆抗氧化能力的指标。在所有组中，出生后第一天后，Trolox等效抗氧化能力的浓度增加，而血浆铁还原能力降低。测量血浆中的氧化应激标志物硫代巴比妥酸反应物质和F2 -异前列腺素，但这些未显示出处理或时间效应。血浆中总蛋白、白蛋白、尿素、乳酸、葡萄糖、非酯化脂肪酸以及胰岛素和皮质醇的浓度随时间变化，但黄酮类化合物补充未引起组间差异。总之，本研究中使用的剂量口服槲皮素和儿茶素对新生奶牛犊牛的健康影响微弱，对其代谢和抗氧化状态无影响。
