Potential role of transgenesis in dairy production and related areas

Historical programs for genetic improvement of dairy cattle are discussed in the context of new genetic technologies resulting in a heterozygous gain of function. Concepts are outlined pointing to the importance of breaking the well established genetic correlation between fat content and protein content of milk to provide flexibility in the dairy industry. The concept of value added genetics is introduced and the economic competitiveness of the mammary glands of livestock are considered in relationship to mammalian cell culture and bacterial fermentation technology.