PSIV-1 Apparent ileal and total tract digestibility of energy and carbohydrates in hybrid rye and other cereal grains fed to growing pigs

Abstract

Abstract An experiment was conducted to test the hypothesis that apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of energy, starch, and total dietary fiber (TDF), and the concentration of ME in 2 hybrids of rye (Bono and Brasetto) are not different from values for barley, wheat, corn, and sorghum. Twenty-four ileal cannulated barrows (28.1 ± 3.0 kg) were placed in metabolism crates and randomly allotted to a 2-period experimental design with 6 diets and 4 replicate pigs in each 13-d period. Diets consisted of 97% of each grain, and no pig received the same diet twice. Urine and feces were collected for 4 d after 5 d of diet adaptation, and ileal digesta were collected on d 12 and 13 of each period. Data were analyzed using the Mixed procedure of SAS with the fixed effect of diet and the random effects of pig and period. The ME (DM basis) was greatest (P < 0.05) in corn and wheat, and least (P < 0.05) in barley, and the ME in Bono and Brasetto rye was 3,499 and 3,459 kcal/kg DM, respectively (Table 1). In all grains, the AID of starch was greater than 90%, and the ATTD of starch was nearly 100%. The AID of TDF was reduced (P < 0.05) in Bono rye compared with all other cereal grains, but the ATTD of TDF was greater (P < 0.05) in Bono and Brasetto rye than in the other grains. In conclusion, the current data indicate that rye results in reduced pre-cecal absorption of energy compared with wheat, corn, and sorghum, but hindgut fermentation of fiber is greater for pigs fed rye. The ME in hybrid rye is not different from values for barley and sorghum, but less than in wheat and corn.