Amino acids and energy utilization in zero-tannin faba bean and co-fermented wheat and corn dried distillers grains with solubles fed to growing pigs1

Abstract

Application of alternative feedstuffs in swine diets will be dependent on characterization of their nutritive value. In 2 experiments, we determined the AA and energy utilization of Manitoba-grown zero-tannin faba beans (ZTFB) and co-fermented wheat and corn dried distillers grains with solubles (wcDDGS). Corn dried distillers grains with solubles (cDDGS) was also included for comparison. In Exp. 1, 6 ileal cannulated barrows (29.3 ± 1.3 kg) were fed 3 diets in a replicated 3 × 3 Latin square design to determine the apparent (AID) and standardized (SID) ileal digestibility of AA. The 3 diets contained ZTFB, wcDDGS, or cDDGS as the sole source of AA. The SID of N and AA were calculated using published values for ileal endogenous N and AA losses from our laboratory. In Exp. 2, 12 intact barrows (22.5 ± 1.1 kg) were fed 4 diets in a two 15-d period crossover design to determine DE and ME contents of the test ingredients by difference method. The diets were a basal corn-based diet or the basal diet with corn replaced by 46% ZTFB, wcDDGS, or cDDGS. The concentrations (DM basis) of GE (kcal/kg), CP (%), and Lys (%) in ZTFB were 4,144, 27, and 1.6, respectively, and corresponding values for wcDDGS were 5,112, 31, and 0.8. The ZTFB had greater (P < 0.05) SID of Lys (87%) compared with wcDDGS (72%) and cDDGS (68%); as a result, the SID content (g/kg DM) of Lys in ZTFB (13.5) was greater (P < 0.05) than that of either wcDGGS (6.03) or cDDGS (6.68). The dried distillers grains with solubles (DDGS) samples had greater (P < 0.05) SID and contents of sulfur AA (Met and Cys) compared with ZTFB. The ME content (kcal/kg DM) of ZTFB (3,548) was less (P < 0.05) than that of cDDGS (3,851) whereas the ME content of wcDDGS (3,669) was similar to that of ZTFB or cDDGS. The results showed that ZTFB has greater digestible Lys whereas wcDDGS has greater digestible sulfur AA but both ingredients have comparable ME content. Therefore, a blend of these 2 ingredients can serve as an excellent source of AA and energy for swine.