This chapter explores issues of nutrigenomics in animal nutrition and production. Many of the bioactive nutrients interact/bind with transcription factors (TFs) to regulate major metabolic pathways to regulate metabolism at the transcriptomic/functional genomics level; this is referred to as nutrigenomics. These potential, other putative functions of food components have created great excitement particularly in the realm of human nutrition and health. To attempt a more metabolic interactive holistic approach, reductionist data are utilized in so-called modeling systems concerning animal nutrition and metabolism for interpretation and application. The most frequent experimental treatments would be a differential gene expression (DE) response study to some food source, specific nutrients/molecules, and varying intakes of a given diet. Such experiments can be completed in a fairly short term and samples taken for appropriate "omics" analyses. The involvement of TF regulating protein synthesis has been much more difficult to identify as this metabolic process is to a large extent under translational or posttranscriptional control.