固体饲料诱发瘤胃发育的生物标志物及其调节机制

Early rumen development is the key to promoting young ruminant production. Physical form and chemical composition of the feed is the inducement of rumen development. The interaction of microbiota and its metabolites with rumen epithelium may be the potential mechanisms with which feed types cause the difference in rumen development. It is observed in our previous experiments that early supplementation of alfalfa with starter improved the rumen development of the lambs. Based on the previous finding, in the proposed project we will take advantage of metagenomics, transcriptomics, metabolomics, digital gene expression profiling, muscle electrophysiology technology to study the evolution of diversity and function of rumen microbiota with the change of physiological stages of lamb from birth to post-weaning, with or without forage supplementation; and to clarify the relationship of microbiota and its metabolites with rumen function. From these results, the biomarkers will be found out for rumen development induced by solid feeds and their function in regulation of evolution of diversity and function of rumen microbiota will be elucidated. The output of this project will contribute to clarify the mechanisms to establish rumen function, and to optimize rumen development.

促进瘤胃尽早发育是幼龄反刍动物生产的关键。饲料物理形态和化学组成是瘤胃发育的诱因，而瘤胃微生物菌群演化及其代谢产物与瘤胃上皮的相互作用可能是不同饲料类型诱发瘤胃发育差异的机制。申请者前期研究发现粗饲料的早期补饲可促进幼龄反刍动物瘤胃发育，为此本项目拟以前期发现为基础，结合宏转录组学、代谢组学、数字基因表达谱分析、肌肉电生理学等技术，研究出生至断奶后的不同生理阶段，以及粗饲料介入情况下，瘤胃微生物菌群多样性和功能演化趋势及其与反刍动物生理状态的相互关系。该研究将筛选出固体饲料诱发瘤胃发育的生物标志物，并探讨其作用机制。为阐明瘤胃功能确立机制，为优化瘤胃功能发育奠定基础。

促进瘤胃尽早发育是幼龄反刍动物生产的关键。饲料物理形态和化学组成是瘤胃发育的诱因，而瘤胃微生物菌群演化及其代谢产物与瘤胃上皮的相互作用可能是不同饲料类型诱发瘤胃发育差异的可能机制。申请前期研究发现粗饲料的早期补饲可促进幼龄反刍动物瘤胃发育，为此本项目以前期发现为基础，结合宏转录组学、代谢组学、数字基因表达谱分析、肌肉电生理学等技术，研究了出生至断奶后的不同生理阶段，以及粗饲料介入情况下，瘤胃微生物菌群多样性和功能演化趋势及其与反刍动物生理状态的相互关系。研究发现补饲苜蓿在断奶前增加瘤胃中unclassified Lachnospiraceae、Treponema和unclassified Ruminococcaceae的相对丰度，增加瘤胃内糖苷水解酶家族的表达量，提高瘤胃微生物碳水化合物降解能力，增加瘤胃中蔗糖、麦芽糖、葡萄糖和异柠檬酸等能源物质的供应；通过上调CAV3、CACNA1D、STAC、GJA1、KCNIP2、RORA、PPARGC1A、NOS2、PRKCB和下调FAM20C，实现瘤胃肌肉细胞的钙内流，促进瘤胃组织发育，从而使羔羊的瘤胃在断奶前就能更好地适应断奶后日粮的转换，减缓断奶应激。该项目为阐明瘤胃功能确立机制，优化瘤胃功能发育奠定基础。