Amino acid digestibility and energy concentration in a novel source of high-protein distillers dried grains and their effects on growth performance of pigs

Three experiments were conducted to evaluate a novel source of high-protein distillers dried grains produced by Buhler Inc. (HP-DDG_Buhler) and fed to growing pigs. The standardized ileal digestibility (SID) of AA in HP-DDG_Buhler and in soybean meal (SBM) was determined in Exp. 1. Nine pigs (109.8 ± 2.78 kg of BW) were fitted with a T-cannula in the distal ileum and allotted to a triplicated 3 × 3 Latin square design with 3 diets and 3 periods per square. Diets containing HP-DDG_Buhler or SBM as the only source of AA and an N-free diet were formulated. The SID of indispensable AA was less (P < 0.01) in HP-DDG_Buhler than in SBM (Arg, 87.5 vs. 93.9%; His, 76.7 vs. 88.7%; Ile, 76.4 vs. 87.5%; Leu, 77.8 vs. 86.8%; Lys, 75.4 vs. 88.4%; Met, 82.8 vs. 88.4%; Phe, 77.9 vs. 87.3%; Thr, 72.5 vs. 83.5%; Trp, 85.1 vs. 91.0%; Val, 73.3 vs. 84.3%). The DE and ME in HP-DDG_Buhler and in corn were measured in Exp. 2 using 16 growing barrows (24.6 ± 1.66 kg of BW). A corn-based diet and a diet containing 50% corn and 48.2% HP-DDG_Buhler were formulated. The total collection method and the difference procedures were used. The concentrations of DE and ME in HP-DDG_Buhler were greater (P < 0.001) than in corn (5,043 vs. 4,002 kcal/kg of DM and 4,690 vs. 3,921 kcal/kg of DM, respectively). Experiment 3 was a 9-wk growth assay using 40 pigs (initial BW: 58.2 ± 2.28 kg) allotted to 5 dietary treatments, with 8 replicates of individually housed pigs per treatment. Treatments included a control diet based on corn and SBM and 4 diets in which HP-DDG_Buhler replaced 33, 66, 66, or 100% of the SBM in the control diet. All HP-DDG_Buhler diets contained supplemental Lys and Thr to provide similar concentrations of SID Lys and Thr in all diets; one of the diets in which HP-DDG_Buhler replaced 66% of the SBM and the diet in which HP-DDG_Buhler replaced 100% of the SBM also contained crystalline Trp. Dietary treatments had no effect on ADG (1.15, 1.13, 1.16, 1.12, and 1.14 kg), ADFI (3.33, 3.35, 3.39, 3.30, and 3.33 kg), or G:F (0.35, 0.34, 0.34, 0.34, and 0.34 kg/kg). Carcass traits of pigs fed the diet in which HP-DDG_Buhler replaced 100% of the SBM were not different from those of pigs fed the control diet. In conclusion, HP-DDG_Buhler contains more DE and ME than corn, but has decreased SID values for AA compared with SBM. Soybean meal can be replaced by HP-DDG_Buhler in diets fed to finishing pigs without any effect on growth performance or carcass characteristics, provided that diets are adequate in indispensable AA.