Phytate Phosphorus Hydrolysis As Influenced by Dietary Calcium and Micro-Mineral Source in Broiler Diets

Phytate phosphorus (PP) hydrolysis by a 3-phytase was studied in vitro at pH 2.5 and 6.5 with either 0, 1.0, 4.0, or 9.0 g of Ca/kg diet, or 0, 1.0, 5.0, 7.5, or 10.0 g/kg diet of micro-mineral premix added as inorganic (IMM) or an equivalent level as micro-mineral-amino acid complexes (MAAC). Adding Ca or micro-minerals reduced (P 0.05) was seen. Therefore, in poultry diets, it is Ca that inhibits PP hydrolysis and decreases P availability.