本试验旨在探究相同饲喂条件下不同品种绵羊羔羊小肠形态和消化酶活性的差异。选取健康的3月龄杜泊羊[（37.90±2.82）kg]、湖羊[（19.20±2.94）kg]和滩羊[（20.67±2.39）kg]公羔各14只，单栏饲喂，预试期15 d，正试期90 d。结果显示：杜泊羊各阶段体重、日增重以及干物质采食量均显著高于湖羊和滩羊（P<0.05），湖羊和滩羊之间无显著差异（P>0.05）。在试验初期（第1~3天）时，杜泊羊干物质、中性洗涤纤维、酸性洗涤纤维表观消化率显著高于湖羊（P<0.05），杜泊羊粗蛋白质表观消化率显著高于湖羊和滩羊（P<0.05）。在试验末期（第88~90天）时，杜泊羊粗蛋白质表观消化率显著高于湖羊和滩羊（P<0.05）。杜泊羊、湖羊十二指肠肌层厚度显著高于滩羊（P<0.05）；杜泊羊回肠绒毛高度/隐窝深度显著高于湖羊和滩羊（P<0.05），肌层厚度显著高于滩羊（P<0.05）。杜泊羊和湖羊空肠淀粉酶活性显著高于滩羊（P<0.05）；湖羊十二指肠脂肪酶活性显著高于滩羊（P<0.05），杜泊羊、滩羊空肠和回肠脂肪酶活性显著高于湖羊（P<0.05）；滩羊十二指肠胰蛋白酶活性最低，回肠胰蛋白酶活性最高，与杜泊羊和湖羊差异显著（P<0.05），湖羊回肠胰蛋白酶活性显著高于杜泊羊（P<0.05）；湖羊十二指肠和回肠糜蛋白酶活性显著高于滩羊（P<0.05），杜泊羊十二指肠糜蛋白酶活性显著低于湖羊（P<0.05），回肠糜蛋白酶活性显著高于滩羊（P<0.05）。综上所述，与滩羊和湖羊相比，杜泊羊的干物质采食量和营养物质表观消化率较高，小肠上皮组织形态较好，小肠淀粉酶和脂肪酶活性较高，因此表现出较好的生长性能。

This study was to explore the differences in small intestinal morphology and enzyme activities of different breed lambs under the same feeding condition. Three-month-old Dorper lambs [(37.90±2.82) kg], Hu lambs [(19.20±2.94) kg] and Tan lambs [(20.67±2.39) kg] were selected as research objects. Each 14 lambs of three breeds with similar health status were selected for 15 days pre-feeding period and single pen feeding for 90 days. The results showed that the body weight and daily gain of different stages, and dry matter intake of Dorper lambs were significantly higher than those of Hu lambs and Tan lambs (P<0.05), but the differences were not significant between Hu lambs and Tan lambs (P>0.05). At the beginning of the experiment (days 1 to 3), the apparent digestibility of dry matter, neutral detergent fiber and acid detergent fiber of Dorper lambs was significantly higher than that of Hu lambs (P<0.05), and the crude protein apparent digestibility of Dorper lambs was significantly higher than that of Hu lambs and Tan lambs (P<0.05). At the end of the experiment (days 88 to 90), the crude protein apparent digestibility of Dorper lambs was significantly higher than that of Hu lambs and Tan lambs (P<0.05). The duodenal muscle layer thickness of Dorper lambs and Hu lambs was significantly higher than that of Tan lambs (P<0.05); the ileal villus height/crypt depth of Dorper lambs was significantly higher than that of Hu lambs and Tan lambs (P<0.05), and the ileal muscle layer thickness of Dorper lambs was significantly higher than that of Tan lambs (P<0.05). The amylase activity of dorper lambs and Hu lambs in jejunum was significantly higher than that of Tan lambs (P<0.05); the lipase activity of Dorper lambs in duodenum was significantly higher than that of Tan lambs (P<0.05), and the lipase activity of Dorper lambs and Tan lambs in jejunum and ileum was significantly higher than that of Tan lambs (P<0.05); the Dorper lambs had the lowest trypsin activity in duodenum and the highest trypsin activity in ileum, and the differences of them were significant compared with Hu lambs and Tan lambs (P<0.05), the trypsin activity in ileum of Hu lambs was significantly higher than that of Dorper lambs (P<0.05); in duodenum and ileum, the chymotrypsin activity of Hu lambs was significantly higher than that of Tan lambs (P<0.05), the chymotrypsin activity in duodenum of Dorper lambs was significantly lower than that of Hu lambs (P<0.05), the chymotrypsin activity in ileum of Dorper lambs was significantly higher than that of Tan lambs (P<0.05). In summary, the dry matter intake and nutrient apparent digestibility of Dorper lambs is higher, the small intestine morphology of Dorper lambs is better, and the activities of amylase and lipase in small intestine of Dorper lambs are higher than those of Hu lambs and Tan lambs, so that Dorper lambs show greater growth performance.