Swine nutrient requirements
Nutritional requirements are defined as the amount of nutrients that pigs require to meet the needs for maintenance, growth, production, reproduction, and other functions. Essentially, pigs have daily requirements for quantities of nutrients to maintain body functions and support productive purposes, including growth, pregnancy, or milk production. Generally, pigs require six classes of nutrients: carbohydrates, proteins, fats, minerals, vitamins, and water.
The most common approaches to estimate nutrient requirements are the factorial and empirical methods. In the factorial approach, the nutrient requirements are obtained by combining the estimated requirements for maintenance and production using a modeling approach. In the empirical approach, the nutrient requirements are defined as the minimal amount of nutrients needed to maximize or minimize a performance criterion using dose-response or titration studies.