[目的] 探索泌乳早期日粮中添加甘草多糖对奶牛生产性能及血清指标的影响。[方法] 采用随机数字表法将60 头体格健康、年龄和胎次相近的经产泌乳早期（产后21 d）奶牛,分成4 组,每组15 头,每组设置3 个重复,每个重复5 头,分别为对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组。对照组只饲喂基础日粮,试验Ⅰ组、试验Ⅱ组和试验Ⅲ组在饲喂基础日粮的基础上,分别添加0.3%、0.6%和0.9%甘草多糖,并在正式试验周期21 d内检测生产性能及血清指标。[结果] 与对照组相比,试验Ⅰ组、试验Ⅱ组和试验Ⅲ组的干物质采食量、产奶量和体重变化均明显升高,且差异显著（P<0.05）;试验Ⅰ组、试验Ⅱ组和试验Ⅲ组的饲料转化率明显降低,且差异显著（P<0.05）;试验Ⅰ组、试验Ⅱ组和试验Ⅲ组血清中的总抗氧化能力、超氧化物歧化酶和谷胱甘肽过氧化物酶的含量均明显升高,且差异显著（P<0.05）;试验Ⅰ组、试验Ⅱ组和试验Ⅲ组血清中的丙二醛含量明显降低,且差异显著（P<0.05）。[结论] 泌乳早期日粮中添加甘草多糖能提升奶牛的生产性能,具有较好的抗氧化能力,其中甘草多糖的最佳使用量为0.9%。

[Objective] To explore the effects of adding glycyrrhetinic polysaccharide to the early lactation diet on the production performance and serum indexes of dairy cows. [Method] This experiment used a random number table method to divide 60 cows with similar physical health,age,and parity during early lactation（21 days postpartum） into 4 groups,with 15 cows in each group.Each group had 3 replicates,with 5 cows in each replicate,including the control group,experiment I,experiment II,and experiment III groups.The early lactation cows in the control group were only fed with a basic diet.On the basis of feeding the basic diet,the early lactation cows in the experimental group I,II,and III were added 0.3%,0.6%,and 0.9% to the basic diet,respectively.The production performance indexes and serum indexes of the early lactation cows were tested within 21 days of the formal experimental week of this experiment. [Result] Compared with the control group,the dry matter intake,milk production,and weight changes of early lactation cows in experiment I,experiment II,and experiment III groups were significantly increased,and the difference was significant（P<0.05）;The feed conversion rate of early lactation cows in experiment I,experiment II,and experiment III groups were significantly decreased,and the difference was significant（P<0.05）;the total antioxidant capacity,content of superoxide dismutase and glutathione peroxidase in the serum of early lactation cows in experiment I,experiment II,and experiment III groups were significantly increased,and the difference was significant（P<0.05）;the content of malondialdehyde in the serum of early lactation cows in experiment I,experiment II,and experiment III groups decreased significantly（P<0.05）. [Conclusion] Adding glycyrrhetinic polysaccharide to the early lactation diet can improve the production performance of cows and have good antioxidant capacity,with the optimal dosage of glycyrrhetinic polysaccharide being 0.9%.