The objective of the present work was to determine if extrusion, pelleting or the combination of extrusion and pelleting has the ability to improve the digestibility of energy and nutrients in diets fed to pigs. The second objective was to determine if the effects of extrusion and pelleting depend on the type of diets that is being fed and if high fiber diets respond differently to feed technologies than low fiber diets. Thus, diets based on corn and soybean meal, corn, soybean meal, and DDGS, or corn, soybean meal, DDGS, and soybean hulls were formulated and each diet was fed either in a meal form, in a pelleted form, in a meal form after extrusion, or in a pelleted form after extrusion. Results indicated that the digestibility of energy in the diets based on corn and soybean meal or corn, soybean meal, and DDGS is improved if diets are pelleted. However, if diets are based on corn, soybean meal, DDGS, and soybean hulls, the improvement in energy digestibility is achieved only if diets are extruded or extruded and pelleted. These results indicate that it is possible to increase the utilization of energy in all types of diets by use of pelleting or extrusion, but the improvement is greatest in high fiber diets that are both extruded and pelleted. The economic feasibility of these technologies depends on the cost of feed and the cost of installing and operating a pellet press and an extruder.
 
Key Findings
• The digestibility of energy and AA in diets based on corn and soybean meal or corn, soybean meal and DDGS is increased if diets are pelleted.
• The digestibility of energy and AA in high fiber diets based on corn, soybean meal, DDGS, and soybean hulls is increased if diets are extruded or extruded and pelleted.
• The increased digestibility of AA that is obtained if diets are pelleted or extruded will result in less soybean meal being needed.
• The increase in energy digestibility and ME of the diets that is a result of pelleting and/or extrusion will result in improved feed conversion rates for pigs fed these diets
• Pelleting and extrusion will reduce the total costs of feed needed to produce a market pig.
This projected was co-founded by the National Pork Board and Bühler AG, Switzerland.