Abstract: The impacts of maternal nutrition on fetal gene expression has gradually become the focus in perinatal life nutrition research. The most important window of developmental plasticity is gestational period. Epigenetics may be implicated in the modification of metabolic genes associated with fetal development by methyl donors. In animal experiments, insufficient or excessive maternal nutrition has been proven to impede the fetal growth. By consulting the scientific reports abroad and in China, this paper discussed the maternal and fetal nutrition needs during gestational period, the roles of hormones in homeostasis regulation, and the importance of energy demands during gestational period on pregnancy health in herbivorous livestock. This paper also summarized the research progress of herbivores nutrition during gestational period in epigenetics, and discussed the application of epigenetic technologies in herbivorous livestock breeding, in hoping to provide references for formulating the best nutrition strategy for herbivores during gestational period, improving embryo quality, and breeding high-quality offspring.

Key words: fetus, programmed development, nutritional restriction, epigenetics