304 Investigating the Impact of Fiber Type and Multicarbohydrase Supplementation on Nutrient Digestibility and Energy Balance of Gestating Sows

Abstract

Abstract Supplementing fiber-degrading enzymes in grow-finish pig diets has been shown to improve energy and nutrient digestibility. However, there is a paucity of research on their effectiveness in gestation diets. The experimental objective was to evaluate the efficacy of multicarbohydrase supplementation in the presence of soluble (20% sugar beet pulp) and insoluble (20% corn DDGS) dietary fiber sources on the apparent total tract digestibility (ATTD) of nutrients and energy balance of sows at mid- and late-gestation. A total of 36 confirmed gestating sows (186 ± 4.6 kg BW) were blocked by parity randomly assigned to 1 of 4 diets (n = 8) in a 2×2 factorial arrangement of treatments on day 28 of gestation. Factors included fiber type of insoluble (IF; 16.91 IDF%) or soluble fiber (SF; 5.26 SDF%) and with (+) or without (-) enzyme supplementation (0.05%, Rovabio Advance P10; Adisseo, Antony, France). Diets were fed from day 28 to 109 of gestation at a feeding level of 2.1 kg (SID-Lys 11 g/d and 4.5 NE-Mcal/d). Diets contained 0.5% of TiO2. Two separate 9-d metabolism periods were conducted on days 50 to 59 (mid-) and 99 to 108 (late-) of gestation. During each period, days 1-3 served as an environmental adaptation period, days 4-7 total urine and feces were collected (96-h) and followed by a 48-h lactulose-mannitol study. Data were analyzed as repeated records using a linear mixed model with block as a random effect, and fiber type, enzyme, and period and their interactions as fixed effects. Multicarbohydrase supplementation increased the ATTD of GE, DM, and NDF by 2.8%, 3.4%, and 8.3%, respectively (Enzyme P < 0.05). There was a tendency for a Period × Fiber × Enzyme interaction for the ATTD of ADF, whereas multicarbohydrase supplementation with SF increased ADF digestibility in mid-gestation by 6.5%, but not in late gestation (P = 0.051). Compared with IF-, the ATTD of hemicellulose was 5.3% greater in sows fed IF+ but did not differ from SF- and SF+ (Fiber×Enzyme P=0.037). Furthermore, in late gestation sows fed IF had 11% greater ATTD of hemicellulose (Period×Fiber P = 0.035). Energy intake did not differ as dictated by design (P = 0.64). Sows fed multicarbohydrases excreted less energy in their urine (519 vs. 469 GE kcal/d; Enzyme P = 0.033) and in their feces (985 vs. 900 GE kcal/d; Enzyme P = 0.003). This resulted in an improvement in both DE (3,723 vs. 3,856 kcal/kg; Enzyme P < 0.01) and ME (3,484 vs. 3,583 kcal/kg; Enzyme P = 0.041), irrespective of fiber type. In late-gestation, sows fed SF tended to have decreased GE excretion compared with IF (Period×Fiber P = 0.091). Sows had a 3.5% greater ME in late-gestation (3,451 vs. 3,572 kcal/kg; Period P < 0.01). In conclusion, multicarbohydrase supplementation increased the energetic contribution of IF and SF in sow diets, and sows have increased fiber and energy digestibility in late gestation.