|Abstract:||Seven experiments were conducted to determine the nutritional value of rice coproducts fed to pigs. In Exp. 1, the objective was to determine the carbohydrate composition and the in vitro total tract digestibility of DM in 5 rice coproducts and to test the hypothesis that in vitro digestibility of DM is negatively correlated with the concentration of non-starch polysaccharides (NSP). Results indicated that broken rice and brown rice contain more starch than full fat rice bran (FFRB) and defatted rice bran (DFRB), whereas rice mill feed had the least concentration of starch. The concentration of soluble dietary fiber (SDF) was between 0.1% in brown rice and 1.9% in rice mill feed. The concentration of insoluble dietary fiber (IDF) was 1.5% in broken rice and 52.9% in rice mill feed. Arabinose and xylose were the main monosaccharides in the fiber fraction of all rice coproducts, but the concentration of these monosaccharides varied among ingredients. The in vitro DM digestibility decreased (P < 0.05) as the concentration of total NSP increased in the ingredients. In Exp. 2, digestibility values of CP and AA in rice coproducts were determined. Results indicated that the SID of CP and Lys in broken rice was greater (P < 0.05) than in other rice coproducts, but the concentration of digestible Lys in DFRB was greater (P < 0.05) than in broken rice and FFRB. In Exp. 3, the hypothesis that the apparent total tract digestibility (ATTD) of nutrients and GE by starter pigs and the concentration of DE and ME in FFRB, DFRB, brown rice, and broken rice is improved if microbial xylanase is added to the diet was tested. Results indicated that concentrations of DE and ME (DM basis) in FFRB and DFRB increased (P < 0.05) if xylanase was used. Broken rice had a greater (P < 0.05) concentration of DE and ME than FFRB and DFRB if no xylanase was added to the diets, but if xylanase was used, no differences in ME among FFRB, brown rice, and broken rice were observed. The ATTD of DM was greater (P < 0.05) in ingredients with xylanase than in ingredients without xylanase. The ATTD of NDF in FFRB was greater (P < 0.05) if xylanase was added to the diet than if no xylanase was used. Experiment 4 was designed to test the hypothesis that the ATTD of GE and nutrients in FFRB and DFRB determined in gestating sows is greater if feed is provided at 1.5 × the ME required for maintenance than at 3.5 × the ME requirement. The second objective of this experiment was to test the hypothesis that the ATTD of GE and nutrients and the concentrations of DE and ME in FFRB and DFRB is not different between growing gilts and gestating sows if both groups of animals are fed 3.5 × the maintenance requirement for ME. Results indicate that there were no effects of level of feed intake of sows on ATTD of GE, DM, OM, or NDF, or on concentrations of DE and ME in FFRB or DFRB. The ATTD of GE, OM, and NDF of FFRB or DRFB was greater (P < 0.05) in gestating sows than in growing gilts. Concentrations of DE and ME in diets were also greater (P < 0.05) if determined in gestating sows than in growing gilts. Concentrations of DE and ME were greater (P < 0.05) in FFRB than in DFRB regardless of feed intake level or the physiological stage of the animals. In Exp. 5, ATTD and standardized total tract digestibility (STTD) of P of 5 rice coproducts were determined. Among the rice coproducts, the greatest (P < 0.05) ATTD and STTD of P was observed for broken rice regardless of inclusion of phytase. If no microbial phytase was used, values for STTD of P in brown rice, FFRB, DFRB, and rice mill feed were not different, but if microbial phytase was included in the diet, ATTD and STTD of P in brown rice was greater (P < 0.05) than in FFRB, DFRB, and rice mill feed. The STTD of P in brown rice, FFRB, and rice mill feed was greater (P < 0.05) if microbial phytase was used than if no microbial phytase was used. Experiments 6 and 7 were designed to test the hypothesis that increasing inclusion levels of FFRB or DFRB does not affect growth performance of weanling pigs or growing-finishing pigs, respectively, if diets are formulated based on values for SID of AA, STTD of P, and ME in all ingredients. In both experiments, a control diet without rice bran and diets containing 10, 20 or 30% FFRB or DFRB were formulated. In nursery pigs, the ADG increased at 10% inclusion of FFRB and decreased at 20 or 30% (quadratic, P < 0.05). The G:F ratio was not affected by inclusion of DFRB, but increased from 0.643 in the control diet 0.682 at 20% inclusion of FFRB in the diet (quadratic, P < 0.05) and the G:F was greater (P < 0.05) in pigs fed diets containing FFRB than in pigs fed diets containing DFRB. In growing-finishing pigs, for the overall experimental period, the ADFI decreased (linear, P < 0.05) and G:F increased linearly (P < 0.05) for pigs fed diets with increasing concentrations of FFRB. The ADFI of pigs fed diets containing DFRB increased linearly (P < 0.05), but G:F decreased (linear, P < 0.05). There were no effects of dietary treatments on carcass or loin quality. The concentration of saturated fatty acids (SFA) in adipose tissue of pigs fed diets containing FFRB decreased (linear, P < 0.05), whereas the concentration of poly unsaturated fatty acids (PUFA) increased (linear, P < 0.05). In conclusion, rice coproducts are sources of energy and AA that may be used in diets for pigs; however, the ATTD of DM and GE may vary among different physiological stages of the animals. Addition of phytase reduced the output of P and improve the STTD of P in rice coproducts. Full fat rice bran and DFRB may be included in diets of weanling or growing-finishing pigs at 10 to 30% without affecting growth performance, and carcass and meat quality also is not affected with the exception that inclusion of FFRB diets for finishing pigs will increase concentrations of PUFA in belly fat of pigs.