Zhang Ke-Hao, Jin Qiong-Yu, Wang Qiang-Jun, Huang Jie, Li Jun-Jiao, Guo Yao, Liu Peng, Liu Zhong-Ying, Liu Dan, Geng Shi-Xia, Li Qin, Li Ming-Yong, Liu Man, Wu Zhong-Hong
State Key Laboratory of Animal Nutrition and Feeding, College of Animal Science and Technology, China Agricultural University, Beijing, China.
College of Animal Science and Technology, Anhui Agricultural University, Hefei, China.
Front Microbiol. 2024 Feb 27;15:1344992. doi: 10.3389/fmicb.2024.1344992. eCollection 2024.
Seasonal environmental shifts and improper eating habits are the important causes of diarrhea in children and growing animals. Whether adjusting feeding time at varying temperatures can modify cecal bacterial structure and improve diarrhea remains unknown. Three batches growing rabbits with two groups per batch were raised under different feeding regimens (fed at daytime vs. nighttime) in spring, summer and winter separately, and contents were collected at six time points in 1 day and used 16S rRNA sequencing to investigate the effects of feeding regimens and season on the composition and circadian rhythms of cecum bacteria. Randomized forest regression screened 12 genera that were significantly associated with seasonal ambient temperature changes. Nighttime feeding reduced the abundance of the conditionally pathogenic bacteria and in summer and in winter. And also increases the circadian rhythmic Amplicon Sequence Variants in the cecum, enhancing the rhythm of bacterial metabolic activity. This rhythmic metabolic profile of cecum bacteria may be conducive to the digestion and absorption of nutrients in the host cecum. In addition, this study has identified 9 genera that were affected by the combination of seasons and feeding time. In general, we found that seasons and feeding time and their combinations affect cecum composition and circadian rhythms, and that daytime feeding during summer and winter disrupts the balance of cecum bacteria of growing rabbits, which may adversely affect cecum health and induce diarrhea risk.
季节性环境变化和不当饮食习惯是儿童和生长中动物腹泻的重要原因。在不同温度下调整喂食时间是否能改变盲肠细菌结构并改善腹泻尚不清楚。将三批生长兔，每批两组，分别在春、夏、冬三个季节按照不同的喂养方案（白天喂食与夜间喂食）饲养，在一天中的六个时间点采集内容物，并用16S rRNA测序研究喂养方案和季节对盲肠细菌组成和昼夜节律的影响。随机森林回归筛选出12个与季节性环境温度变化显著相关的属。夜间喂食降低了夏季和冬季条件致病菌和的丰度。并且还增加了盲肠中昼夜节律性扩增子序列变体，增强了细菌代谢活动的节律。盲肠细菌的这种节律性代谢特征可能有利于宿主盲肠中营养物质的消化和吸收。此外，本研究确定了9个受季节和喂食时间组合影响的属。总体而言，我们发现季节、喂食时间及其组合会影响盲肠组成和昼夜节律，并且在夏季和冬季白天喂食会破坏生长兔盲肠细菌的平衡，这可能对盲肠健康产生不利影响并引发腹泻风险。
