Microbial Phytase Supplementation

A report out of Spain told of a broiler experiment to study the effect of microbial phytase (Napuphos 500) supplement on chick performance, mineral retention, bone and plasma minerals, and serum enzyme activities. The treatments consisted of adding 0 or 500U/kg phytase to diets containing 0.35 or 0.22% nonphytate phosphorus (1 day to 3 weeks) or 0.35 and 0.22% nonphytate phosphorus (3 to 6 weeks). The phytase treatment increased weight gains (P>0.05) at both three and six weeks and feed consumption at three weeks. Phytase did not alter feed utilization. Reducing the nonphytate phosphorus increased (P>0.0001) phosphorus retention at three and six weeks of age; increased magnesium retention at six weeks; and reduced (P>0.0001) calcium and zinc retention at both three and six weeks. Phytase supplementation increased (P>0.0001) phosphorus, calcium, magnesium and zinc retention at three and six weeks of age. Phytase supplementation increased tibia weight, tibia ash, magnesium and zinc concentrations; and reduced the relative liver weight. Phytase also increased plasma phosphorus level and serum aspartate aminotransferase activity; reduced plasma calcium and magnesium contents; and reduced serum alanine aminotransferase, alkaline phosphatase and lactate dehydrogenase activities. These results indicate that phytase additions to low-phosphorus diets improved chick performance, mineral utilization, and several serum enzyme activities.

Viveros, A. and co-workers. 2002. Effects of microbial phytase supplementation on mineral utilization and serum enzyme activities in broiler chicks fed different levels of phosphorus. Poultry Sci. 81(8): 1172-1183.