PSVII-5 Influences of feed intake and fiber source on energy and nutrient digestibility in growing pigs

Abstract

Abstract The objective was to determine the influence of feed intake (FI) and fiber source on the apparent total tract digestibility (ATTD) of gross energy (GE) and nutrients in pigs. Twelve barrows with an initial body weight (BW) of 34.0 ± 2.6 kg were allotted to a replicated 6 × 4 Latin square design with 6 treatments and 4 periods. The 6 treatments were consisted of a 2 × 3 factorial arrangement with 2 amounts of FI (9.0 and 4.5% × BW0.75) and 3 dietary fiber sources. Three diets were 1) a corn-soybean meal-based basal diet (BD), 2) a diet replacing 30% of corn and soybean meal in BD with sugar beet pulp (SBP) as a source of soluble dietary fiber (SDF), and 3) a diet replacing 15% of corn and soybean meal in BD with corn cobs as a source of insoluble dietary fiber (IDF) to obtain a similar IDF concentration as in the SBP diet. Following a 6-d adaptation, feces were collected for 5 d. The ATTD of GE, dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) in diets was greater (P < 0.05) for pigs fed at 4.5% of BW0.75 compared with those fed at 9.0% of BW0.75. The ATTD of GE, DM, OM, NDF, and ADF in SBP diet was greater (P < 0.01) than that in corn cob diet. However, there was no interaction between FI and fiber source on energy and nutrient digestibility. The ATTD of GE, DM, OM, protein, NDF, and ADF in SBP was greater (P < 0.01) than that in corn cobs. In conclusion, energy and nutrient digestibility values were increased by reduced feed intake and were greater in sugar beet pulp than in corn cobs without interaction between feed intake and fiber source.