Using Extruded-Expelled Soybean Meal in Swine Diets

Jason Woodworth, Graduate Research Assistant Extrusion processing is an effective means of improving the nutritional value of whole soybeans fed to swine. Recently, Insta-Pro International has combined extrusion technology with expelling, an oil extraction process, to produce an extruded-expelled soybean meal (Insta-Pro ExpressTM extruder/press system). The resulting soybean meal contains slightly higher levels of fat (approximately 5 vs 1%, respectively) than conventional, solvent-extracted soybean meal, and the higher energy could lead to improved feed efficiency. The nutritional value of dry, extruded-expelled soybean meal has not been determined for swine, therefore a series of trials were designed to determine the nutritional adequacy of the new protein source. Experiment 1. Our first study was designed to determine the apparent ileal digestibility of amino acids for dry, extruded-expelled soybean meal with or without hulls and compare the values to solvent extracted 46.5% CP soybean meal. Experiment 2. The second trial was designed to determine the digestible (DE) and metabolizable (ME) energy values of the same soybean meal sources used in Exp. 1. Experiment 3. A total of 216 pigs (initially 23.3 lb and 35 d of age; 14 d post-wean) was used in a 21-d growth trial to determine the influence of different soybean meal processing techniques on weanling pig growth performance. Six experimental diets fed in meal form were designed to form three pre-planned comparisons. Using the apparent ileal digestible amino acid coefficients and ME values determined in Exp. 1 and 2, two diets were formulated using dry, extruded-expelled soybean meal with or without hulls. Pigs fed one of these diets were compared with those fed corresponding corn-44% CP (with hulls) or 46.5% CP (without hulls) solvent-extracted soybean meal diets with added soy oil. Soy oil was added Using Extruded-Expelled Soybean Meal in Swine Diets