State Key Laboratory of Grassland Agro-ecosystem, Engineering Research Center of Arid Agriculture and Ecological Remediation of Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, China.
Qinghai Provincial Key Laboratory of Adaptive Management on Alpine Grassland, Qinghai University, Xining, China.
J Sci Food Agric. 2021 Jan 15;101(1):82-90. doi: 10.1002/jsfa.10617. Epub 2020 Jul 25.
Early weaning in yak calves is being attempted to improve yak reproduction rate. However, this has to be done with caution because of the high mortality rate of calves due to the lack of nutrients and the harsh environmental conditions. Twenty-four weaned male yak calves were used in a 60 day feeding trial in which astragalus root extract (ARE) was supplemented. They were assigned randomly to one of four dietary treatments (n = six per treatment) that differed in ARE level: 0 g kg (control), ARE ; 20 g kg , ARE ; 50 g kg , ARE and 80 g kg dry matter intake (DMI), ARE .
Final bodyweight and average daily gain (ADG) were significantly higher and the DMI/ADG ratio was significantly lower in calves with ARE supplementation than control (ARE ) calves. Ruminal concentrations of acetate and propionate and serum concentration of superoxide dismutase in ARE calves were higher than in the other groups and serum concentration of insulin was higher in ARE calves than in ARE calves. Serum immunoglobulin G (IgG) and interleukin-2 (IL-2) concentrations in ARE-fed calves were higher than in controls. Serum tumor necrosis factor (TNF-α) concentration was higher in ARE and ARE groups than ARE calves and serum interleukin-6 (IL-6) concentration was higher in ARE than in ARE calves. Serum immunoglobulin A (IgA), IgG and immunoglobulin M (IgM) concentrations increased with age in ARE-fed calves. ARE supplementation increased the abundance of fiber degrading bacteria.
ARE at a dosage of 5% to 8% DMI can be supplemented to early weaned yak calves to improve growth performance, antioxidant capacity and immunity. © 2020 Society of Chemical Industry.
为提高牦牛繁殖率，尝试对牦牛犊进行早期断奶。但是，由于缺乏营养和恶劣的环境条件，犊牛死亡率很高，因此必须谨慎进行。在一项为期 60 天的饲养试验中，使用了 24 头断奶雄性牦牛犊，在其中添加了黄芪根提取物（ARE）。将它们随机分配到四种不同饲料处理组（每组 6 头），饲料中 ARE 的水平分别为：0 g·kg（对照组）、ARE ；20 g·kg、ARE ；50 g·kg、ARE 和 80 g·kg 干物质采食量（DMI）、ARE。
与对照组（ARE）犊牛相比，添加 ARE 的犊牛最终体重和平均日增重（ADG）显著提高，DMI/ADG 比显著降低。ARE 犊牛瘤胃乙酸和丙酸浓度以及血清超氧化物歧化酶浓度高于其他组，血清胰岛素浓度高于 ARE 犊牛。与对照组相比，ARE 喂养犊牛的血清免疫球蛋白 G（IgG）和白细胞介素-2（IL-2）浓度较高。ARE 和 ARE 组犊牛血清肿瘤坏死因子（TNF-α）浓度高于 ARE 犊牛，而 ARE 组犊牛血清白细胞介素-6（IL-6）浓度高于 ARE 犊牛。与对照组相比，ARE 喂养犊牛血清免疫球蛋白 A（IgA）、IgG 和免疫球蛋白 M（IgM）浓度随年龄增长而增加。ARE 补充剂增加了纤维降解菌的丰度。
以 5%至 8% DMI 的剂量向早期断奶的牦牛犊补充 ARE 可以提高生长性能、抗氧化能力和免疫力。 © 2020 化学工业协会。
