The objective was to test the hypothesis that digestible energy (DE), metabolizable energy (ME), standardized ileal digestibility (SID) of amino acids (AA), and standardized total tract digestibility (STTD) of P in soybean meal produced from a new variety of soybeans (Photoseed) are not different from conventional soybean meal (SBM-CV). In Exp. 1, thirty pigs (18.3 ± 1.3 kg) were randomly allotted to a corn diet or 2 diets containing corn and Photoseed or corn and SBM-CV. Pigs were housed in metabolism crates and feces and urine were collected for 4 d after 5 d of adaptation. Feces and urine were analyzed for gross energy and DE and ME were calculated for each ingredient. The statistical model included ingredient as fixed effect and replicate as random effect and pig was the experimental unit. Results indicated that DE and ME of Photoseed were not different from DE and ME in SBM-CV (Table 1). In Exp. 2, nine barrows (30.0 ± 1.5 kg) with a T-cannula in the distal ileum were allotted to a triplicated 3 × 3 Latin Square design with 3 diets and 3 periods in each square. An N-free diet and diets containing SBM-CV or Photoseed were used. Pigs were housed individually in fully slatted pens and ileal digesta were collected on d 6 and 7 of each period. Digesta samples were lyophilized, ground, and analyzed for AA, and SID of AA was calculated. The statistical model included diet as fixed effect and square, period, and pig as random effects, and pig was the experimental unit. Results indicated that the SID of Arg, Ile, and Lys were not different between the two ingredients (Table 2), but the SID of other indispensable AA were greater (P < 0.05) in SBM-CV than in Photoseed. In Exp. 3, forty-eight barrows (12.0 ± 1.6 kg) were allotted to 6 diets with 8 pigs per diet. The SBM-CV or Photoseed were included in diets with 3 levels of microbial phytase (0, 500, or 1,000 units/kg). Pigs were housed in metabolism crates and feces were collected quantitatively for 4 d after 5 d of adaptation. Fecal samples were dried and analyzed for P and the STTD of P was calculated. The statistical model included ingredient, phytase, and the interaction between ingredient and phytase as fixed effects and replicate as the random effect. The pig was the experimental unit. Results indicated that inclusion of phytase in the diets increased (P < 0.05) the STTD of P, but STTD of P in Photoseed was not different from the STTD in SBM-CV (Table 3).
In conclusion, no differences in DE and ME, STTD of P, and SID of some indispensable AA between Photoseed and SBM-CV were observed.