Effects of Diet Particle Size on Pig Growth Performance, Diet Flow Ability, and Mixing Characteristics

Cereal grains are the primary energy source in swine diets. Therefore, not only must producers be concerned about the composition of the grain, but also how it is processed so the pig can fully utilize the nutrients. Because feed represents 65 to 75 percent of overall production costs in a swine operation, improving the efficiency of feed utilization will have a tremendous impact on the cost of production. Not only is proper particle size reduction important for improving profitability, it will also have an effect on nutrient excretion and the impact of swine waste on the environment. Nearly all feed ingredients will be subjected to some type of particle size reduction. Particle size reduction increases the surface area of the grain, thus allowing for greater interaction with digestive enzymes. It also improves the ease of handling and the mixing characteristics. However, fine grinding will increase the energy costs of feed processing and may result in feed bridging, dust problems, and increase the incidence of gastric ulcers in swine. Bridging of bins and feeders has recently become a focus in production management as these “out of feed” events may be a stressor contributing to finishing pig disease.