Abstract
Two experiments were conducted to determine the standardized ileal digestibility (SID) of CP and AA, apparent total tract digestibility (ATTD) of GE, and DE and ME in conventional distillers dried grains with solubles (DDGS-CV) and in a novel source of high-protein distillers dried grains with solubles (DDGS-HP) produced by Lincolnway Energy (Nevada, IA). In Exp. 1, 18 barrows (initial BW: 72.47 ± 9.16 kg) that had a T-cannula installed in the distal ileum were allotted to a completely randomized design with 3 diets and 6 replicate pigs per diet. A nitrogen-free diet and 2 diets that contained cornstarch and DDGS-CV or DDGS-HPLincolnway as the sole source of CP and AA were formulated. Diets were fed to pigs for 7 d, and ileal digesta were collected on days 6 and 7 of each period. The SID for Leu, Lys, Met, Phe, and Glu was greater (P < 0.05) in DDGS-HPLincolnway than in DDGS-CV, and the SID of Ile, Val, and total indispensable AA, as well as the SID of Tyr, tended to be greater (P < 0.10) in DDGS-HPLincolnway than in DDGS-CV. No difference between DDGS-CV and DDGS-HPLincolnway was observed for the SID of CP and all other AA. In Exp. 2, 24 barrows (initial BW: 52.80 ± 2.55 kg) were housed individually in metabolism crates and randomly allotted to 1 of 3 diets. A corn-based basal diet (97.25% corn) and 2 diets that contained corn and DDGS-CV or corn and DDGS-HPLincolnway were formulated. Each diet was fed to 8 pigs. Feces and urine were collected using the marker to marker approach with 7-d adaptation and 5-d collection periods. The DE and ME in DDGS-CV and DDGS-HPLincolnway were calculated using the difference procedure. The DE and ME in DDGS-HPLincolnway on an as-fed basis were greater (P < 0.05) than in corn and DDGS-CV, but the ATTD of GE in DDGS-HPLincolnway and DDGS-CV was less (P < 0.01) than in corn. In conclusion, the SID of some AA and the DE and ME in DDGS-HPLincolnway were greater than in DDGS-CV.