The experiment was carried out to determine the minimum fecal endogenous losses, the P requirement of pigs, and the true P absorption from phosphate dicalcium using pigs in the final of the growing phase through the isotopic dilution technique. Twenty commercial hybrid pigs, 48kg L.W., were arranged in experimental design complete randomized blocks with five treatments and four replications. Treatments consisted of different total P levels: 0.33, 0.36, 0.47, 0.54 and 0.61%. Fecal and urinary P outputs, absorption and retention of P were influenced by P intake; P endogenous losses were not affected by P intake, indicating that dietary P was not enough to achieve P requirements; the P biological availability from dicalcium phosphate was 74.7%; and the daily maintenance dietary requirement for pigs was 10.02mg P/kg L.W.
Swine; phosphorus; isotopic dilution; true absorption; requirement
