Nutritive value of corn distiller’s dried grains with solubles steeped without or with exogenous feed enzymes for 24 h and fed to growing pigs1.

The use of corn distillers dried grains with solubles (<bold>DDGS</bold>) in pig diets is limited due to high fiber concentration. Steeping with exogenous fiber-degrading enzymes (<bold>FDE</bold>) may improve their feeding value. We evaluated apparent ileal digestibility (<bold>AID</bold>), standardized ileal digestibility (<bold>SID</bold>), and apparent total tract digestibility (<bold>ATTD</bold>) of components and DE content in DDGS steeped without or with two commercial FDE (A and B). Mixture of 350 g of DDGS, FDE (none for control), and 1.5 liters of water was incubated at 40 °C for 24 h with 15 min agitation every 40 min. FDE-A (pure combination) supplied 5,500 U of xylanase and 1,050 U of β-glucanase while FDE-B (multienzyme complex) supplied 1,200 U of xylanase, 150 U of β-glucanase, 500 U of cellulase, and 5,000 U of protease per kg of DDGS plus side activities. Samples were taken at time 0, 4, 8, and 24 h for organic acids and pH measurements. Three semi-purified corn starch–based diets were formulated with steeped DDGS as the sole source of CP. The basal mixture contained 0.2% TiO₂ as indigestible marker. Six ileal-cannulated pigs (20 kg BW) were fed the three diets in a replicated 3 × 3 Latin square design to give six replicates per diet. Pigs were fed at 2.8× maintenance energy requirements and had free access to water. In each period, pigs were adjusted to diets for 7 d followed by 2 d for grab fecal and 2 d of 8 h continuous ileal digesta collection. There were no (<italic>P</italic> > 0.05) treatment and sampling time interaction or treatment effects on pH and lactic concentration. Lactic and acetic acids increased, and pH decreased (<italic>P</italic> < 0.05) over time points. The AID of CP, NDF, and crude fat and SID of CP were not different (<italic>P</italic> > 0.05) among treatments. Steeping DDGS with FDE-A had lower (<italic>P</italic> = 0.01) ATTD of NDF than control but higher (<italic>P</italic> = 0.001) ATTD of crude fat compared with the control or DDGS steeped with FDE-B. Values for DE content in steeped DDGS were not different (<italic>P</italic> > 0.05) and amounted to 4,095, 4,039, and 3,974 kcal/kg DM for the control, FDE-A, and FDE-B, respectively. In conclusion, under conditions of the study, steeping DDGS with exogenous enzymes did not improve fiber and energy digestibility. [ABSTRACT FROM AUTHOR]