Comparison of Natuphos and Phyzyme as phytase sources for commercial layers fed corn-soy diet.

The objective of this experiment was to compare the effects of 2 sources of phytase on performance of commercial Leghorns fed corn-soy diets. Seven diets were fed to Hy-line W-36 hens (n = 840; 8 replicates of 15 hens per treatment) from 21 to 33 wk of age. The treatments consisted of a control diet containing 0.38% nonphytate P (NPP) and a 2 x 3 factorial arrangement of 2 dietary NPP concentrations (0.11 and 0.26%) with 2 phytase sources [Natuphos (BASF, Mt. Olive, NJ) and Phyzyme (Danisco Animal Nutrition, Carol Stream, IL)] and without phytase. Dietary NPP had significant effects on feed intake, NPP intake, total P intake, egg production, egg weight, egg mass, egg specific gravity, and excreta P. The addition of Phyzyme or Natuphos significantly increased egg production and egg mass of hens fed the P-deficient diet (0.11% NPP) to levels that were similar to hens fed the control diet containing 0.38% NPP. Feed intake of hens fed the diets supplemented with Phyzyme or Natuphos was significantly less than that of hens fed the control diet containing 0.38% NPP. Phyzyme or Natuphos supplementation in the diets containing 0.11% NPP had significantly reduced excreta P of the control diet (approximately 58 and 54%, respectively) with no adverse effect on egg production and egg mass. There were no significant differences in feed intake, NPP intake, total P intake, egg production, egg weight, egg mass, feed conversion, egg specific gravity, mortality, BW, and excreta P between the diets supplemented with Natuphos and the diets supplemented with Phyzyme. In conclusion, Phyzyme had the same positive effects on performance of commercial Leghorns fed corn-soy diets as Natuphos.