A study was conducted to determine the apparent metabolizable energy corrected for nitrogen (AMEn) contents of by-products from the soybean oil industry for broiler chickens. A total of 390 Cobb male broilers were randomly distributed into 13 treatments having six replicates of five birds each. Birds were fed a common corn-soybean meal starter diet from placement to 21 days. The four fat sources were added at three increasing levels each, and were fed from 21 to 28 d. The fat sources utilized were acidulated soybean soapstock, glycerol, lecithin and a mixture containing 85% soapstock, 10% glycerol and 5% lecithin. A 4 × 3 + 1 factorial arrangement was used with 4 by-products (ASS, GLY, LEC, or MIX), 3 inclusion levels and 1 basal diet. Each of the four fat by-product sources was included in the diets as follow: 2% of by-products (98% basal + 2% by-product), 4% (96% basal + 4% by-product), or 6% (94% basal + 6% by-product). Total excreta were collected twice daily for 72 hours to determine apparent metabolizable energy contents starting at 25 d. The AMEn intake was regressed against feed intake and the slope was used to estimate AMEn values for each fat source.

The resultant AMEn values calculated for the soybean oil by-product were 7,153, 3,916, 7,051, and 8,515 kcal/kg DM for acidulated soybean soapstock, glycerol, lecithin and the mixture, respectively. These results provide AMEn values for soybean oil by-products that can be used in poultry feed form.