本文研究了不同水平植物提取精油混合物(essential oil mixtures，EOM)对肉仔鸡生长性能、肠道菌群和肠黏膜形态的影响。试验选取600只体重相近的7日龄爱拔益加（AA）雄性肉仔鸡，随机分为5个处理，每个处理8个重复，每个重复15只鸡，分别饲喂添加0、20 mg/kg金霉素及40、80和160 mg/kg EOM的玉米-豆粕型饲粮。结果表明，EOM和金霉素对平均日增重、平均日采食量和料重比均有改善趋势，EOM的效果好于金霉素，但各处理间差异不显著（P>0.05）；EOM显著提高回肠和盲肠乳酸杆菌（21 d）数量（P<0.05），其中160 mg/kg EOM显著降低了回肠（43 d）、盲肠大肠杆菌和金黄色葡萄球菌数量（P<0.05）；EOM显著提高了回肠（21 d）的绒毛高度和隐窝深度比（villus height to crypt depth ratio，VCR）（P<0.05）。结果表明，饲粮中添加EOM可刺激肠道有益菌生长、降低有害菌增殖及改善肠道功能，具有提高肉鸡生长性能的作用，本试验条件下EOM的适宜添加量为160 mg/kg。

This study was conducted to evaluate the effects of supplemental plant essential oil mixtures in broiler diets on performance, intestinal microflora and intestinal mucosa morphology. Arbor Acres chicks (n=600, 1-day-old, male) were randomly allotted into 5 treatments, each treatment consisted of 8 replicates with 15 birds each. Five treatments consisted of no addition of EOM or antibiotic (control group), 20 mg/kg aureomycin, 40, 80 and 160 mg/kg EOM in the corn-soybean meal diets. The results showed that EOM was tended to improve the growth performance during the whole experimental period, although the effects were not significant (P>0.05). EOM increased Lactobacillus number in ileum (d 21) and caecum (P<0.05). The supplementation of 160 mg/kg EOM reduced E. coli number in ileum (d 43) and caecum (P<0.05) as well as S.aureus number in ileum and caecum (P<0.05). EOM increased villus height to crypt depth ratios in ileum (d 21) (P<0.05). The results indicate that EOM has the function of improving growth performance and regulating microflora as well as intestinal mucosa morphology. The appropriate supplemental amount of EOM is 160 mg/kg under this experimental condition.［Chinese Journal of Animal Nutrition，2011，23（3）：433-439］