Energy and phosphorus values of sunflower meal and rice bran for broiler chickens using the regression method

The energy and phosphorus values of sunflower meal (SFM) and rice bran (RB) were determined in 2 experiments with Ross 708 broiler chickens from 15 to 22 d of age. In Exp.1, the diets consisted of a corn-soybean meal reference diet (RD) and 4 test diets (TD). The TD consisted of SFM and RB that partly replaced the energy sources in the RD at 100 or 200 g/kg and 75 or 150 g/kg, respectively, such that the equal ratios were maintained for all energy containing ingredients across all experimental diets. In Exp.2, a cornstarch-soybean meal diet was the RD and TD consisting of SFM and RB that partly replaced cornstarch in the RD at 100 or 200 g/kg and 60 or 120 g/kg, respectively. Addition of SFM and RB to the RD in Exp.1 linearly decreased (P < 0.01) the digestibility coefficients of DM, energy, ileal digestible energy (IDE), metabolizability coefficients of DM, nitrogen (N), energy, N correct energy, metabolize energy (ME), and nitrogen-corrected ME. Except for RB, the increased levels of the test ingredients in RD did affect the metabolizability coefficients of N. The IDE values (kcal/kg DM) were 1,953 for SFM and 2,498 for RB; ME values (kcal/kg DM) were 1,893 for SFM and 2,683 for RB; and MEn values (kcal/kg DM) were 1,614 for SFM and 2,476 for RB. In Exp.2, there was a linear relationship between phosphorus (P) intake and ileal P output for diets with increased levels of SFM and RB. In addition, there was a linear relationship between P intake and P digestibility and retention for diets with increased levels of SFM. There were a quadratic effect (P < 0.01) and a tendency of quadratic effect (P = 0.07) for P digestible and total tract P retained, respectively, in the RB diets. The P digestibility and total tract P retention from regression analyses for SFM were 46% and 38%, respectively.