The aim in this work was to evaluate two mathematical models on the study of the flow of the phosphorus in metabolism of swines aiming at highlighting the most efficient model and indicating the highest potential phosphosrus source to be used in nutrition for swines. It was used 21 hybrid barrow at 32 kg initial weight fed diets based on corn, soybean meal and vegetal oil, supplemented with dicalcium phosphate, monodicalcium phosphate, triple superphosphate, simple superphosphate, Catalão rock phosphate or phosphoric acid as sources of phosphorus. The experiment was arranged in randomized blocks, with seven treatments and three replicates and one animal per experimental unity. Metabolism data and kinetics of phosphorus in tissues obtained by the isotopic dilution technique were used for development of the two models. The models presented similarity and efficiency in the determination of the estimates of the phosphorus flow in the anatomical compartments. Simple superphosphate and dicalcium phosphate have more potential to be used in growing swines. However, dicalcium phosphate presentes better adjustment in the models and it can be used as a standard for nutrition of growing swines.
endogenous phosphorus; isotopic dilution; mathematical model; metabolism; radiophosphorus
