Effect of supplemental enzyme on growth performance, digesta viscosity, apparent total tract digestibility of nutrients in nursery pigs

Abstract Text: Arabinoxylans and mannans are present in high concentration in coproducts like distillers dried grain with solubles (DDGS) which are not degraded by endogenous enzymes of swine, increases the digesta viscosity, and subsequently reduces the digestibility of nutrients. Feed enzymes can mitigate the negative effect of fibers thereby enhancing the utilization of relatively low-cost coproducts in swine feeding. Three enzymatic treatments (xylanase, mannanase, and xylanase + mannanase) were used in a 20 days feeding trial to evaluate the effect of supplemental enzymes on fiber degradation and nutrient digestibility in nursery pigs fed corn-soybean meal based diet with 15% DDGS. A total of 32 weaner pigs (PIC 337 × Camborough 22, initial BW 6.2 kg) were used in the study. Feed intake and BW were recorded weekly. On d 14, titanium dioxide was blended into experimental diet (0.3%) as an indigestible marker for calculation of digestibility. Fecal samples were collected over 3 consecutive days from d 17 to 19. On d 19, pigs were fasted overnight and exactly 4 h after refeeding on d 20 in the morning, pigs were euthanized by captive bolt followed by exsanguination. There was no significant effect of enzymes on growth performance of pigs as 20 days period might not have been sufficient to show the change as well as on pH of jejunal, ileal and colon digesta. Addition of xylanase reduced (P < 0.05) the viscosity of jejunal digesta (2.1 to 1.5 centipoise) and increased (P < 0.05) apparent total tract digestibility (ATTD) of acid detergent fiber (18.1 to 26.9%) and neutral detergent fiber (35.1 to 41.2%). Addition of mannanase tended to increase (P = 0.060) ATTD of neutral detergent fiber (35.1 to 41.4%). In conclusion, use of feed enzymes targeting fiber in coproducts degrades fiber, increases fiber digestibility and decreases the viscosity of digesta which ultimately increases the digestion and absorption of nutrients.

Keywords:  coproducts, enzymes, fiber digestibility