Energy Concentration and Amino Acid Digestibility in two sources of Canola Meal fed to Growing Pigs
Two experiments were conducted to determine DE and ME and standardized ileal digestibility (SID) of CP and AA by growing pigs in a novel canola meal (CM-HP) produced from high protein canola seeds and to compare these values with DE, ME, and SID values determined in conventional canola meal (CM-CV) and soybean meal (SBM). In Exp.1, 32 growing barrows (initial BW: 47.25 ± 6.23 kg) were individually housed in metabolism cages and randomly assigned to 4 treatments in a randomized complete block design with 8 replicates per treatment. The 4 diets included a corn-based basal diet and 3 diets formulated by mixing corn and each source of canola meal or SBM. Fecal and urine samples were collected for 5 d following a 5-d adaptation period. The DE and ME in CM-HP, CM-CV, and SBM were calculated using the difference procedure. Concentrations of DE and ME in CM-HP and CM-CV were less (P < 0.05) than in corn and SBM (DE: 3,419 and 3,104 vs. 4,012 and 4,305 kcal/kg DM, respectively; ME: 2,842 and 2,720 vs. 3,854 and 3,894 kcal/kg DM, respectively). No differences in concentrations of DE and ME were observed between CM-HP and CM-CV. In Exp. 2, eight growing barrows (initial BW: 46.4 ± 5.6 kg) had a T-cannula installed in the distal ileum and randomly allotted to a replicated 4 × 4 Latin square design with 4 diets and four 7-day periods in each square. Three diets that contained CM-HP, CM-CV, or SBM as the sole source of CP and AA were formulated, and a N-free diet was also used. Ileal digesta were collected on d 6 and 7 of each period. The SID of CP and most AA in CM-HP and CM-CV were less (P < 0.05) than in SBM. The SID of CP in CM-HP was greater (P < 0.05) than in CM-CV. However, no differences were observed in SID of any AA between CM-HP and CM-CV. The concentration of standardized ileal digestible CP and almost all AA was greater (P < 0.05) in SBM than in CM-HP and CM-CV, and CM-HP contained more (P <0.05) standardized ileal digestible CP and AA than CM-CV. In conclusion, increased concentration of CP in canola meal does not compromise the DE and ME and the AID or SID of AA. The novel CM-HP supplies more digestible AA than CM-CV.
Keywords: amino acid digestibility, canola meal, energy concentration