Digestibility of amino acids, energy, acid hydrolyzed ether extract, and neutral detergent fiber, and concentration of digestible and metabolizable energy in low-oil distillers dried grains with solubles fed to growing pigs1

Abstract

Abstract Two experiments were conducted to test the hypothesis that digestibility of amino acids (AA), gross energy (GE), acid hydrolyzed ether extract (AEE), and neutral detergent fiber (NDF), and values for metabolizable energy (ME) in low-oil distillers dried grains with solubles (DDGS) vary among suppliers. In Exp. 1, the apparent total tract digestibility (ATTD) of GE, AEE, and NDF, and concentration of ME were determined in eight sources of DDGS (sources A, B, C, D, E, G, H, and I). A corn-based basal diet and eight diets containing corn and each source of DDGS were fed to 72 barrows (initial body weight = 18.1 ± 1.3 kg) with eight pigs per diet. Feces and urine were collected for 5 d after 7 d of adaptation. The ME did not differ among the eight sources of DDGS with the exception that DDGS source E contained less (P < 0.05) ME than DDGS source D. The ATTD of GE did also not differ among the eight sources of DDGS, but ME and ATTD of GE in corn were greater (P < 0.05) than in the eight sources of DDGS. However, the ATTD of AEE in corn and the eight sources of DDGS was not different, but the ATTD of AEE in DDGS source E was greater (P < 0.05) than in DDGS source A. The ATTD of NDF in DDGS source D was also greater (P < 0.05) than in DDGS sources E, G, and H, but ATTD of NDF did not differ between corn and the eight sources of DDGS. In Exp. 2, standardized ileal digestibility (SID) of AA was determined in seven sources of DDGS (sources A, B, C, D, E, G, and H). Twenty-four barrows (initial body weight = 63.4 ± 3.4 kg) that had a T-cannula installed in the distal ileum were allotted to a two-period incomplete Latin square design with eight diets. Seven diets were formulated to contain each of the seven sources of DDGS and an N-free diet was also used. Ileal digesta were collected for 2 d after 5 d of adaptation. There were no differences between pigs fed DDGS sources A and B in SID of AA, and the SID of Lys, Met, and Trp did not differ among DDGS sources A, B, and E. However, SID of most indispensable and dispensable AA except Gly were greater (P < 0.05) in DDGS source B than in DDGS sources C, D, E, G, and H. In conclusion, variability in SID of AA, ATTD of NDF and AEE, and ME were observed among the sources of DDGS used in this experiment.