[目的]探讨黄芪多糖对奶牛生产性能、抗氧化能力和免疫功能的影响,为提高奶牛养殖效益及健康管理提供理论依据。[方法]选取72 头胎次、泌乳量及体况相似的奶牛,随机分为4组：对照组（CON）、低剂量组（APS 1.5）、中剂量组（APS 3.0）和高剂量组（APS 4.5）。对照组饲喂基础日粮,其余三组在基础日粮中分别添加1.5、3.0、4.5 g/kg黄芪多糖。预试期15 d,正试期60 d,期间监测并分析产奶量、乳成分、抗氧化指标及免疫指标。[结果]APS 3.0组日产奶量显著提高,乳蛋白率、乳脂率及干物质含量有所改善,体细胞数显著降低;各试验组血清总抗氧化能力（T-AOC）、超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）活性显著升高,丙二醛（MDA）含量显著降低;添加黄芪多糖组免疫球蛋白IgA、IgM含量显著提高,肿瘤坏死因子-α（TNF-α）含量显著降低,且中剂量组效果最优。[结论]黄芪多糖能显著提升奶牛生产性能,增强抗氧化能力和免疫功能,其中3.0 g/kg添加量效果最佳,具有较高的养殖应用价值。

[Objective] To investigate the effects of Astragalus polysaccharides on production performance, antioxidant capacity and immune function of dairy cows,and to provide theoretical basis for improving dairy cattle breeding efficiency and health management. [Method] Seventy-two cows with similar first litter,milk production and body condition were selected and randomly divided into four groups：control group （CON）,low-dose group （APS 1.5）,medium-dose group （APS 3.0） and high-dose group （APS 4.5）.The control group was fed the basal diet,and the other three groups were fed the basal diet supplemented with 1.5,3.0,and 4.5 g/kg Astragalus polysaccharide,respectively.The pre-experimental period lasted 15 d,and the formal experimental period lasted 60 d.during which milk production,milk composition,antioxidant indicators and immune indicators were monitored and analyzed. [Result] Milk production in the APS 3.0 group was significantly improved,milk protein rate,milk fat rate and dry matter content were improved,and somatic cell number was significantly reduced;serum total antioxidant capacity （T-AOC）,superoxide dismutase （SOD）,glutathione peroxidase （GSH-Px） activities were significantly increased,and malondialdehyde （MDA） content was significantly reduced in each experiment group;The immunoglobulin IgA and IgM contents in the astragalus polysaccharide-supplemented groups were significantly increased,while the tumor necrosis factor-α (TNF-α) content was significantly decreased,with the medium-dose group showing the optimal effect. [Conclusion] Astragalus polysaccharide cansignificantly improve the production performance of dairy cows,enhance antioxidant capacity and immune function,among which 3.0 g/kg addition has the best effect and has high application value in breeding.