生产中因乏情、受胎率低等繁殖障碍导致母猪淘汰率高，主要原因在于卵泡发育受阻和卵母细胞质量不佳。鼠上研究证实，细胞内感知营养代谢状态的腺苷酸活化蛋白激酶（AMPK）和雷帕霉素靶蛋白复合物1（mTORC1）信号可调控原始卵泡激活与发育。申请人前期研究发现，母猪饲喂富含纤维日粮显著影响第1胎及随后繁殖性能。但是，日粮纤维是否通过其代谢底物短链脂肪酸（SCFAs）或代谢激素血清素调控卵巢AMPK和mTORC1信号影响原始卵泡激活和发育仍未见报道。本项目首先明确日粮纤维对母猪原始卵泡激活与发育的调控效应，筛选母猪原始卵泡适度激活的纤维水平；进一步通过颈静脉恒流灌注技术、卵巢及颗粒细胞培养模型研究SCFAs或血清素与AMPK和mTORC1信号通路的互作关系在母猪原始卵泡激活与发育中的作用。本研究对揭示日粮纤维营养与卵泡发育的机理具有重大理论意义，并对提高母猪短期和长期繁殖力具有重要的实践意义。

Anestrous and low conception rate resulting from impaired follicle development and oocyte quality is the contributing factor for the large proportion of culling sows in commercial swine farms. AMPK and mTORC1, acting as the key proteins to sense the cellular metabolic switch, are recently demonstrated to govern the awakening of primordial follicles and their subsequent maturation in mice. Preliminary research in our laboratory revealed an improved reproductive performance not only in the first parity but also the subsequent five parties in sows fed diets supplemented with an appropriate ratio of dietary fiber. However, it remains unclear whether the awakening and maturation of primordial follicles could be controlled by the ovarian AMPK and mTORC1 signaling pathways induced by the dietary fiber derived metabolic signals, short-chain fatty acids (SCFAs) or serotonin. In this project, the regulation of awakening and development of primordial follicles in gilts fed a dietary fiber rich diet will be investigated firstly, and an appropriate level of dietary fiber will be optimized. Moreover, the metabolic signals induced by dietary fiber will be validated for their roles in the regulation of primordial follicle awakening and development using exogenous infusion test. Finally, the role of AMPK and mTORC1 signaling pathway in control of primordial follicle awakening and maturation by SCFAs or serotonin will be investigated using ovary culture in vitro and granulosa cell culture in vitro. The results of this project will disclosure the relationship between dietary fiber and follicle development, and have a practical significance to improve the fertility of sows in a short and lifetime manner.