幼龄梅花鹿瘤胃微生物定植、起源及介导的代谢表型的研究

Sika deer (Cervus nippon) is an important ruminant belonging to the Cervidae family. Rumen microbiota of adult sika deer plays important roles in the nutrient digestion and absorption, energy supply, and regulating the host health and function. We have investigated the rumen microbiota of adult sika deer in previous studies, however, the microbial diversity of adult sika deer is depend on the colonized microbiota in the rumen of juvenile sika deer. Up to now, the information of the colonization and origin of rumen microbiota in juvenile sika deer is absent. Therefore, in this study, we will apply high-throughput technology and systems biology to examine the rumen microbiota and metabolic phenotypes from different time points of juvenile sika deer, (1) to illustrate the mechanism of colonization of rumen microbiota in the rumen of juvenile sika deer, the change of the metabolic phenotypes, and the patterns of interaction of the metabolics and microbiota in the rumen of juvenile sika deer, and (2) to elucidate the internal relationship between the microbiota from the mater and pens, and the colonized rumen microbiota of juvenile sika deer. These data will be used to understand the mechanism of rumen microbial ecology of juvenile sika deer in the points of microbiota and metabolomics, and may provide the important information in regulating the microbial ecology and the function in the rumen of juvenile sika deer.

梅花鹿是我国的一种名贵鹿科反刍动物。瘤胃微生物在成年梅花鹿的饲料消化、营养物质吸收、能量供应及调控正常生理等方面起重要作用。前期我们已经研究了成年梅花鹿瘤胃微生物区系，然而，成年梅花鹿瘤胃微生物多样性却受幼龄阶段瘤胃定植微生物的影响，目前我们对幼龄阶段梅花鹿瘤胃微生态的变化规律及瘤胃微生物的起源仍不清楚。因此，本研究以出生到成年的幼龄梅花鹿为研究对象，基于不同时间点的瘤胃微生态，从微生物和代谢特征出发，采用高通量技术与系统生物学理论，研究幼龄梅花鹿瘤胃微生物定植规律、代谢产物变化规律及二者之间的互作关系，以期揭示幼龄梅花鹿瘤胃微生态变化规律；同时探究母体不同部位和圈舍微生物与幼龄梅花鹿瘤胃定植微生物之间的内在关系，以期阐明影响梅花鹿瘤胃微生物起源的因素。研究结果将从微生物学和代谢组学角度揭示幼龄梅花鹿瘤胃微生态的建立机制，并对幼龄梅花鹿瘤胃微生态及其功能的调控具有重要意义。

瘤胃微生物在成年梅花鹿的饲料消化与营养物质吸收等方面起重要作用。前期我们已经研究了成年梅花鹿瘤胃微生物区系，然而，成年梅花鹿瘤胃微生物多样性却受幼龄阶段瘤胃定植微生物的影响，目前我们对幼龄阶段梅花鹿瘤胃微生态的变化规律及瘤胃微生物的起源仍不清楚。因此，本研究首先研究了河麂、驯鹿和山羊母乳中细菌结构，研究结果表明河麂与驯鹿母乳形成了特异性的细菌群落；对1，42和70日龄（断奶后10天）梅花鹿空肠、回肠、盲肠和结肠的微生物和代谢物进行了研究。结果表明随着日龄的增加，空肠和回肠细菌多样性增加，细菌结构和代谢物发生了显著改变。Halomonas spp.，Lactobacillus spp.，Escherichia–Shigella和Bacteroides spp.的比例随着日龄的增加度降低，而Intestinibacter spp.，Cellulosilyticum spp.，Turicibacter spp.，Clostridium sensu stricto 1和Romboutsia spp.的丰度增加。随着日龄的增加，蛋氨酸，苏氨酸和腐胺的浓度在空肠和回肠中都显著增加。Bacteroides spp.，Escherichia-Shigella，Clostridium sensu stricto 1和Lactobacillus spp.比例降低，而Ruminococcaceae UCG 005，Ruminococcaceae UCG 010，Rikenellaceae RC9和Prevotellaceae UCG 003的丰度增加。盲肠和结肠中肌酸和丝氨酸的浓度降低，而短链挥发性脂肪酸，壬酸和亮氨酸的浓度增加；发现瘤胃中甲烷菌主要是Methanobrevibacter spp.，而盲肠则是Methanocorpusculum，表明了甲烷菌的分布可能受到生境的影响。