Abstract: The purpose of this study was to explore the effect of fermented Chinese medicine on the intestinal flora structure of broilers under heat stress，and to provide theoretical support for the prevention and control of heat stress and the research on the mechanism of heat stress.180 Ross 308 broilers were randomly divided into six groups with three replicates per group and 10 broilers per replicate. Control group was routine feeding；Broilers in each heat stress group were fed at 34 ℃. The heat stress control group was fed with basal diet under heat stress.In the heat stress experimental group，0.5 g/kg，1.0 g/kg and 1.5 g/kg fermented Chinese medicine and 1.5 g/kg unfermented Chinese medicine were added to the diet of broilers.Feeding lasted for 14 d.The composition of cecum flora of broilers in each group was detected by high⁃throughput detection technology based on 16S rDNA amplicon. The number of Lactobacillus，Salmonella and Escherichia coli in cecum of broilers in each group was counted by plate colony counting method. The results showed that the effect of adding 1.5 g/kg fermented Chinese medicine in broiler diet was the best. Compared with the heat stress control group，the average daily weight gain and average daily feed intake of broilers under heat stress were significantly increased by 36.30% and 26.42%，respectively，and the feed to meat ratio was significantly decreased by 8. 82%. Blautia abundance increased in cecum，the number of Lactobacillus increased by 25. 04%，and the number of Escherichia coli and Salmonella decreased by 11.25% and 13.74%，respectively. The above results showed that fermented traditional Chinese medicine could improve the growth performance of broilers under heat stress，regulate the cecum flora of broilers，increase the number of beneficial bacteria and reduce the number of harmful bacteria.

Key words: Fermented Chinese medicine, Heat stress, Broiler, Flora structure, Intestinal tract

摘要： 探究发酵中药对热应激肉鸡肠道菌群结构的影响，为肉鸡热应激防控提供理论支持。试验选取180只罗斯308肉鸡，随机分为6组，每组设3个重复，每个重复10只。空白对照组常规饲养，热应激组肉鸡在34 ℃条件下饲养，热应激对照组在热应激条件下饲喂基础日粮，热应激试验组肉鸡日粮中分别加入0.5、1.0、1.5 g/kg发酵中药和1.5 g/kg未发酵中药。饲喂14 d。利用基于16S rDNA扩增子的高通量检测技术检测各组肉鸡盲肠菌群组成，采用平板菌落计数法统计各组肉鸡盲肠中乳酸杆菌、沙门氏菌和大肠杆菌数量。结果显示，肉鸡日粮中加入1.5 g/kg发酵中药效果最佳，与热应激对照组相比，能使热应激肉鸡平均日增质量和平均日采食量分别显著增加36.30%和26.42%，料肉比显著降低8.82%；增加盲肠中Blautia 属丰度，乳酸杆菌数量增加25.04%，大肠杆菌和沙门氏菌数量分别降低11.25% 和13.74%。以上结果表明，发酵中药能提高肉鸡在热应激状态下的生长性能，调节肉鸡盲肠菌群，增加有益菌数量并降低有害菌数量。

关键词: 发酵中药, 热应激, 肉鸡, 菌群结构, 肠道