This study evaluated the replacement value of supplemental Natuphos for ino
rganic phosphorus in broiler diets. Four levels of dicalcium phosphate were
compared: 25, 50, 75, and 100% of the level required to supply 0.47% and 0
.45% available P in wheat/corn/soybean meal starter and grower diets, respe
ctively (referred to as control levels). Natuphos (a commercial phytase) wa
s added at 0, 50, 100, and 150% of the recommended dosage (600 FTU/kg). The
results of this study indicate that even without Natuphos supplementation,
the level of dicalcium phosphate in the diet can be reduced to 75% of the
control level without a loss in body weight gain or feed conversion. This r
epresented a reduction in total phosphorus from 0.72 to 0.64%. A further re
duction in total phosphorus to 0.56% was possible with Natuphos supplementa
tion at 50% of the recommended dosage. Broilers on such a diet excreted one
third less P than those on the control diet. An increase in Natuphos suppl
ementation (i.e., 100 and 150% of recommended dose) yielded no further incr
ease in the replacement value of Natuphos for dicalcium phosphate.