Impact of research with cattle, pigs, and sheep on nutritional concepts: body composition and growth.

Studies with pigs, cattle, and sheep have provided a wealth of information regarding growth and body composition. Most of this information has been obtained using the standard methods for measuring the body composition of meat animals, which consist of dissection and chemical analysis. These methods have been used with meat animals to validate a variety of in vivo techniques that are used in both animal and human body composition studies. Research on the growth and body composition of meat animals has provided important concepts regarding the relation between growth and composition, including chemical maturity, the effects of severe undernutrition, partitioning of nutrients under various physiological conditions, the efficiency of nutrient utilization, and compensatory growth following a period of undernutrition. In addition, several genetic and physiological conditions affecting growth and body composition have been identified in meat animals that serve as important models for both animal and human growth.