Digestibility and net energy prediction of rice by products determined with piglets

ABSTRACT: The aim of this study was to determine the chemical composition, digestibility, and net energy (NE) of broken rice (BRR), stabilized rice bran (SRB), and parboiled rice bran (PRB) for piglets. Two digestibility trials were performed with 12 and 18 male pigs with initial weights of 8 and 16kg, respectively. We performed total fecal collection using ferric oxide as fecal marker. The digestibility coefficients of organic matter, crude protein, and gross energy were higher (P<0.001) for the BRR compared to the SRB and PRB. The PRB presented a digestible energy 2% lower than that of BR and 5% higher than that of SRB. For BRR, average NE value was 3,228kcal/kg dry matter (DM), and the difference between the lower and higher value was 311kcal/kg DM. Average NE values of SRB and PRB were 2,896 and 3,293kcal/kgDM, respectively. The difference between the energy predicted by each equation reached 190kcal/kgDM for SRB and 285kcal/kgDM for PRB. In conclusion, BRR showed higher nutrient digestibility coefficients, except for EE and GE, which can be attributed to differences in the production processes. Regardless of the type of feedstuff tested, equations to predict NE values should be used carefully due to considerable differences in energy content.