Growth performance, gastrointestinal and digestibility responses in growing pigs when fed corn-soybean meal-based diets with corn DDGS treated with fiber degrading enzymes with or without liquid fermentation.

Fermenting high fiber ingredients such as DDGS with feed enzymes may improve their feeding value. We investigated the effects of fermenting corn DDGS with a blend of β-glucanase and xylanases (XB) on growth performance, gut parameters and apparent total tract digestibility (ATTD) of nutrients and energy in growing pigs. Dietary treatments were: 1) corn soybean meal-based diet plus 30% DDGS (control), 2) control + XB without fermentation (XBNS), and 3) control + DDGS fermented with XB (16% DM) for 3 to 10 d at 40°C (XBS). Target activities in XB were 1,050 and 5,500 U/g of DDGS for β-glucanase and xylanases, respectively. Diets contained phytase at 750 FTU/kg. Feed samples were taken during fermentation and at feeding for analysis of pH and organic acids. A total of 144 pigs (25 ± 1.0 kg BW) were assigned to pens (3 barrows and 3 gilts) and allocated to the 3 diets in a 2-phase feeding program (3-wk/phase). Diets on ad libitum bases and were delivered by a computer controlled liquid feeding system at a feed to water ratio of 1:4, four times/d. Pigs had free access to water. Fecal samples were taken in the final 3 d of Phase 2 to determine ATTD using TiO2 marker method and 1 pig/pen was euthanized for gastrointestinal (GIT) measurements. The pH of diets at feeding time was lower (P < 0.01) for XBS (4.72) compared with control (5.45) and XBNS (5.45). Pigs fed XBNS had higher (P = 0.04) ADG than control in Phase 1. In phase 2 and the overall (wk 0-6), ADG and final BW were higher (P = 0.01) for XBNS than XBS but were not different (P > 0.05) from control. There were no diet effects (P > 0.05) on ADFI. Feed to gain (FCR) for XBNS (1.68) and XBS pigs (1.69) was better (P < 0.01) than for control pigs (1.78) in Phase 1. There were no diet effects (P > 0.05) on FCR in phase 2 or in the overall. Pigs fed XBNS had lower (P < 0.01) ATTD of CP than control and XBS fed pigs. Although not different (P > 0.05) from control, pigs fed XBNS had lower (P < 0.05) jejunal crypt depth and ATTD of gross energy than pigs fed XBS. In conclusion, treating corn DDGS with XB with or without liquid fermentation improved feed efficiency in phase 1 suggesting degradation of dietary fibrous components that may limit nutrient utilization in younger pigs. However, these benefits were not observed in phase 2.