Effect of phytase on the biological availability of phosphorus by means of isotopic dilution technique, in whole rice meal based diets, for swines

This experiment was carried out to determine the endogenous fecal losses of P and the effect of phytase on the biological availability of P in the diets and in the whole rice meal (WRM) for growing swines, by means of the isotopic dilution technique. The barrows were allotted to a complete randomized experimental design, with four treatments and three replicates. The treatments consisted on two diets without WRM (with or without 1250 FTU [Unit of Phytase Activity]/kg diet), with 0.34% total P, and other two diets with WRM (with or without 1250 FTU/kg of diet), with 0.56% total P. An the 11th day, each animal was intravenously injected with 7.4 MBq P-32. The endogenous fecal losses of P were not affected by the action of phytase. The phytase addition reduced the total P excreted in the feces and improved the absorption and the biological availability of P of diets with whole rice meal.