目的 探讨饲粮中添加黄芪多糖对尼罗罗非鱼生长、饵料系数、肠道组织学和血清指标的影响，为黄芪多糖在罗非鱼饲料中的合理应用提供依据。 方法 以基础饲粮为对照组，试验组在基础饲料中添加0.5 g/kg的黄芪多糖，饲喂给初始体质量相近的尼罗罗非鱼。饲喂8周后，分别测定生长性能与形体指标、肌肉常规组分、消化酶活性和血清抗氧化能力，并对肠道组织切片进行观察。 结果 与对照组相比，添加黄芪多糖的处理组末质量提高21.25 g、增质量率提高63.11百分点，饵料系数降低0.29。黄芪多糖组肌肉粗脂肪显著提高0.08百分点。添加黄芪多糖组肠绒毛高度增加63.16 μm，肌层厚度增加4.57 μm，均显著高于对照组；肠道中淀粉酶和脂肪酶的活性明显增加。氨氮攻毒试验后，饲粮中添加黄芪多糖显著提高罗非鱼肠道超氧化物歧化酶SOD活性，第3天提高6.37 U/L，血清过氧化氢酶CAT活性也有提高，但差异不显著。 结论 在饲料中添加黄芪多糖能够提高尼罗罗非鱼的生长性能、肠道消化、形态以及氨氮攻击下的抗氧化能力。

Objective To investigate the effects of dietary addition of Astragalus polysaccharides on the growth, feed coefficient, intestinal histology, and serum indices of Nile tilapia, providing a basis for the rational application of Astragalus polysaccharides in tilapia feed. Methods The basal diet was used as a control group, while the experimental group received an additional 0.5 g/kg of Astragalus polysaccharides in the basal feed, forming two isonitrogenous and isolipidic diets that were fed to Nile tilapia of similar initial body weight. After 8 weeks of feeding, growth performance and body indices, muscle routine components, digestive enzyme activity, and serum antioxidant capacity were measured, and intestinal tissue sections were observed. Results Compared to the control group, the treatment group with added astragalus polysaccharides showed an increase in final mass by 21.25 g, a weight gain rate improvement by 63.11 percentage points, and a feed conversion ratio reduction of 0.29. The muscle crude fat in the astragalus polysaccharide group significantly increased by 0.08 percentage points. The villus height of the intestines in the Astragalus polysaccharide group increased by 63.16 μm, and the thickness of the muscular layer increased by 4.57 μm, both significantly higher than those of the control group; the activity of amylase and lipase in the intestines significantly increased. After the ammonia nitrogen challenge test, the addition of astragalus polysaccharides to the diet significantly enhanced the intestinal superoxide dismutase (SOD) activity in tilapia, increasing by 6.37 U/L on the third day, and also increased the serum catalase (CAT) activity, although the difference was not significant. Conclusions The addition of Astragalus polysaccharides to the feed can improve the growth performance, intestinal digestion, morphology, and antioxidant capacity under ammonia nitrogen challenge of Nile tilapia.