Defining Swine Nutrient Requirements and AllowancesWhat do the Numbers Mean?

1999 University of Nebraska-Lincoln Extension Swine Report. Defining nutrient requirements or allowances is the first, and conceivably most important step, in developing a nutrition program for growingfinishing pigs. Understanding the terminology and underlying principles used to define nutrient requirements and allowances for pigs will help producers better evaluate their nutrition programs. This information will also enable producers to interface production outputs (e.g., growth rate and carcass data) to published nutrient requirement and allowance programs, such as The National Research Council, Nutrient Requirements of Swine, 1998. As these and other approaches describing nutrient requirements for pigs develop, producers need a better and more complete understanding of growth biology in order to help them accurately determine the nutritional needs of their pigs. Because of the diminishing-return response of growth and biological traits to nutrient intake or concentration, the added costs associated with increasing nutrient densities at or near the requirement must be carefully considered.