The costs of ingredients supplying energy in swine diets contribute the largest portion of total feed costs. Energy is not considered as a nutrient but is required to maintain all body functions and support productive purposes.
The main energy sources for swine are the cereal grains corn, milo, wheat, barley, and their co-products. In cereal grains, starch and oil are positively correlated with energy values, whereas fiber is negatively correlated. In addition, fat, which contains approximately 2.5 times the amount of energy as cereal grains, is often used to increase the energy density of swine diets.