The Nutritional Importance of Muscle Protein Turnover in Pigs

In economic terms, muscle is the most important tissue for pig producers. Research has been largely focused, therefore, on the means by which to increase carcass muscle content, as well as the efficiency of nutrient use for muscle growth. Since a major component in this tissue is protein, the rate at which protein is continuously synthesized and degraded, i.e. the rate of protein turnover, is related to growth and, particularly, to feed efficiency for growth. Thus, protein turnover is of nutritional importance. Furthermore, turnover is primarily dependent on intrinsic factors such as age, sex or genotype, which are generally related to a specific hormone status. However, most of the time, these intrinsic factors interact with nutrients either through stimulation of hormone secretion or production in an endocrine, or autocrine or paracrine way, andlor through action at the receptor level. The present paper describes some of the nutrient-hormone signals involved in the regulation of muscle protein turnover in pigs.