Zhao Fei, Zhao Quanmin, Li Songze, Zhu Yuhang, Si Huazhe, Feng Jiang, Li Zhipeng
College of Life Science, Jilin Agricultural University, Changchun 130118, China.
College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China.
Animals (Basel). 2024 Dec 14;14(24):3606. doi: 10.3390/ani14243606.
The reindeer () is a circumpolar member of the Cervidae family, and has adapted to a harsh environment. Summer is a critical period for reindeer, with peak digestibility facilitating body fat accumulation. The gut microbiota plays a pivotal role in nutrient metabolism, and is affected by captivity. However, differences in the composition of the gut microbiota and metabolites between captive and grazing reindeer during summer remain poorly understood. Here, we conducted a comparative study of the fecal microbiota and metabolites between captive ( = 6) and grazing ( = 6) male reindeer, using full-length 16S rRNA gene sequencing and gas chromatography-time-of-flight mass spectrometry, respectively. Our results indicated that , , , , and were the predominant genera in the feces of reindeer. However, microbial diversity was significantly higher in captive reindeer compared to their grazing counterparts. Principal coordinate analysis revealed significant differences in the fecal microbiota between captive and grazing reindeer. In captive reindeer, the relative abundances of the genera , , , , , , and were significantly higher, while those of the genera , , , and were significantly lower. A comparison of predicted functions indicated that pathways involved in fat digestion and absorption, histidine metabolism, lysine biosynthesis, and secondary bile acid biosynthesis were more abundant in captive reindeer, whereas the pathways of fructose and mannose metabolism and propanoate metabolism were less abundant. An untargeted metabolomic analysis revealed that 624 metabolites (e.g., amino acids, lipids, fatty acids, and bile acids) and 645 metabolites (e.g., carbohydrates and purines) were significantly increased in the feces of captive and grazing reindeer, respectively. In conclusion, we unveiled significant differences in fecal microbiota and metabolites between captive and grazing male reindeer, with the results suggesting a potentially enhanced ability to utilize plant fibers in grazing reindeer.
驯鹿（）是鹿科的一种环极地动物，已适应了恶劣的环境。夏季对驯鹿来说是一个关键时期，消化率达到峰值有助于身体脂肪积累。肠道微生物群在营养代谢中起关键作用，并受圈养影响。然而，夏季圈养和放牧驯鹿之间肠道微生物群和代谢物组成的差异仍知之甚少。在此，我们分别使用全长16S rRNA基因测序和气相色谱-飞行时间质谱，对圈养（n = 6）和放牧（n = 6）雄性驯鹿的粪便微生物群和代谢物进行了比较研究。我们的结果表明，、、、、和是驯鹿粪便中的主要属。然而，圈养驯鹿的微生物多样性显著高于放牧驯鹿。主坐标分析显示圈养和放牧驯鹿的粪便微生物群存在显著差异。在圈养驯鹿中，、、、、、、和属的相对丰度显著更高，而、、、和属的相对丰度显著更低。预测功能的比较表明，参与脂肪消化和吸收、组氨酸代谢、赖氨酸生物合成和次级胆汁酸生物合成的途径在圈养驯鹿中更为丰富，而果糖和甘露糖代谢以及丙酸代谢途径则较少。非靶向代谢组学分析显示，圈养和放牧驯鹿粪便中分别有624种代谢物（如氨基酸、脂质、脂肪酸和胆汁酸）和645种代谢物（如碳水化合物和嘌呤）显著增加。总之，我们揭示了圈养和放牧雄性驯鹿粪便微生物群和代谢物的显著差异，结果表明放牧驯鹿利用植物纤维的能力可能增强。
