Nutritional and hormonal regulation of energy metabolism in skeletal muscles of meat-producing animals

Abstract

In meat-producing animals, skeletal muscle is a tissue of major economic importance. Energy metabolism of skeletal muscle should be assessed in relation to its main physiological functions which are growth as well as posture, physical activity and thermogenesis. These functions have specific energy requirements which may entail competition in the utilization of energy-yielding nutrients, and modify the efficiency of ATP production and use. In this review, the energy requirements of muscles will be presented as well as the main metabolic pathways involved in the utilization of carbohydrate and lipids for energy supply and deposition. Regulation of metabolism will also be tackled in relation to the major physiological functions of skeletal muscle in various domestic species. Special focus will be given to the energy metabolism of growing muscle and its interactions with meat quality. The question will be asked whether the optimization of the efficiency of ATP production and utilization in muscle for nitrogen retention is compatible with an improvement of meat quality (as partly determined by glycogen and lipid deposition)? For this purpose, the interactions between muscle carbohydrate, lipid and protein metabolism will be reviewed.