Transcriptomics-based research initiatives will enable bovine researchers and producers to ask key questions about diet and its effects on bovine health and performance. By focusing on gene expression and functional genomics, we can gain a more definitive understanding of the importance of dietary intervention in nutritional strategies.  Whilst still rapidly evolving and expanding, this new scientific frontier will revolutionise our thinking about how dietary supplementation can have such dramatic and beneficial responses on whole body health. Functional genomic studies utilising real-time PCR and high-density microarrays are providing new ways for researchers to rapidly evaluate the effects of diet, environment and disease processes on bovine growth and performance.