Impacts of environment on gene expression and epigenetic modification in grazing animals

Understanding how physiology is altered by the animal's environment including its epigenetic, nutritional and management exposure is a major challenge in optimizing livestock breeding and production. Considerable efforts have been expended in developing techniques for examining gene expression and its regulatory mechanisms such as epigenetic modifications, genetic determinants, nutritional factors and animal production systems. In this review, the technological advances in gene expression and epigenomics in livestock are discussed. Some examples of how these techniques have been used to improve our understanding of the nutritional and management regulation of gene expression, impacts of gene expression on animal performance, and impacts of epigenetics on the response of grazing livestock to changing nutritional and management environments are examined. These examples and the knowledge generated by future research in this area will allow for optimizing the efficiency of our grazing livestock production systems through improved animal genetic evaluation, nutrition, management, and production practices.