Significance, origin, and function of bovine milk proteins : the biological implications of manipulation or modification

The rapid advances in technology for both evaluating and understanding the structure of animal genomes and their functional significance have presented opportunities for scientists to more clearly understand the complexity of bovine milk proteins and the control of their expression. Used in conjunction with protein data, we can begin to understand the significance of naturally occurring genetic variation influencing milk protein production and composition, as well as how milk proteins are processed into the biologically active peptides that are resident within colostrum and milk. The challenge then remains to translate this information into useful food and therapeutic products, helping to underpin the commercial viability of the dairy industry. Recent advances in genetic technologies provide the potential for accelerated selection of existing traits. Of course, composition could be manipulated via genetically modified (GM) approaches, although consumer acceptance of GM foods is still a major issue. In this chapter, we present a review of the current status of bovine milk genomics and functional genomics and describe the roles, characteristics, and key bioactivities of the major bovine milk proteins and their encrypted peptides. The application of modern molecular analytical tools to the full spectrum of lactation strategies adopted by eutherians, marsupials, and monotremes to improve our understanding of the milk proteome is also discussed.