Gut microbiome, as the largest and most important micro-ecosystem, plays a critical role in health. The purpose of this study was to evaluate whether heat stress modulates the composition and diversity of the gut microbiome in rats. The heat stress model was prepared in rats with the heating temperature maintained at 35–38°C. Cecum contents were collected after heat stress for 3 h and days 1, 3 and 7. Total DNA was extracted for 16 S rRNA sequencing and analysis of intestinal microbiome composition and diversity. The study showed that the composition of the intestinal microbiome of heat stress group was changed. And the heat stress modulated key phylotypes of gut microbiota at the level of phylum and genus. In particular, the genus of Lactobacillus and Bacteroides were significantly reduced, whereas the Oscillospira and Clostridium were increased by heat stress. Meanwhile, the rats under the heat stress encountered the change in carbohydrate metabolism, amino acid metabolism, and membrane transport to defense against stress. Taken together, the composition and structure of gut microbiome were affected by heat stress and some key phylotypes were also significantly altered. We conclude that the heat stress could impact multiple biological functions, via altering the gut microbiome.

肠道微生物组作为最大和最重要的微生态系统，在健康中起着至关重要的作用。本研究的目的是评估热应激是否会调节大鼠肠道微生物组的组成和多样性。在大鼠中制备热应激模型，加热温度保持在35-38°C。在热应激 3 小时和第 1、3 和 7 天后收集盲肠内容物。提取总 DNA 用于 16 S rRNA 测序和肠道微生物组组成和多样性分析。研究表明，热应激组肠道菌群的组成发生了变化。并且热应激在肠道和属水平上调节肠道菌群的关键系统型。特别是乳杆菌属和拟杆菌属显着减少，而Oscilospira和Clostridium 则因热应激而增加。同时，热应激下的大鼠会遇到碳水化合物代谢、氨基酸代谢和膜转运的变化，以抵御应激。总之，肠道微生物组的组成和结构受到热应激的影响，一些关键的系统发育型也发生了显着改变。我们得出结论，热应激可以通过改变肠道微生物群来影响多种生物学功能。