The source of phosphorus of better quality for use in the pig feeding and that cause less environment impact by the excretion of phosphorus in the enviroment was evaluated. Twenty-one male pigs weighting 34.94 ± 2.88 were fed corn-soybean meal based diets supplemented with different P sources: control without P supplementation P (Cont), dicalcium (FBC), monodicalcium (MBC), triple superphosphate (ST), simple superphosphate (SS), Catalão rock (Rocha) and phosphoric acid (AcF). The experiment was designed to evaluate the P availability and P excretion to environment. The experiment was arranged in randomized blocks, with seven treatments and three replicates and one pig/box. The model was deterministic and compartimental, in which the gastrointestinal tract (GIT) (C1), plasma C2, bones (C3) and soft tissues (liver, heart, kidney and muscle) (C4) represented the compartments. Metabolism data and kinetics of P in tissues were obtained by the isotopic dilution technique. The simple superphosphate is the phosphorus source with the smallest capacity for polluting the environment, best bioavailability and most efficient use for the metabolism of growing swine.
biomatematic model; endogenous phosphorus; isotopic dilution; metabolism; radiophosphorus
