Although much is known about the basic pathways of lipid metabolism and their regulation in farm animals, the processes of lipid accretion and lipid secretion in milk will continue to assume great importance in future research. This prominence is stimulated by the tremendous impact that lipid synthesis has on the efficiency, or inefficiency, of meat and milk production.
In turn, this directly affects profitability of livestock enterprises. Lipid metabolism also plays a key role in development of metabolic disorders such as fatty liver, ketosis and pregnancy toxaemia, which continue to plague livestock producers.
Supplemental fats are now standard components of diets fed to high-producing dairy cows, and are common in both swine and beef diets. Continued efforts to enhance the digestibility and utilization of dietary fatty acids will improve the energetic efficiency of milk and meat production.
Increased understanding of lipid metabolism should lead to practical approaches to enhance the productivity and health of farm animals. Various biotechnological approaches to manipulate the process of growth or milk production, such as somatotropin, target key aspects of lipid synthesis. Development of transgenic livestock may be able to exploit desirable pathways or overcome limitations in others to alter lipid metabolism. Finally, unravel- ling the roles and metabolism of the lipid- derived cell signalling mechanisms will have a huge impact on understanding the cellular processes of growth in farm animals, as well as on the cellular mechanisms underlying homeostatic actions of circulating hormones and growth factors.
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