Animal Science Department


Date of this Version



Published in American Society of Agronomy, Crop Science Society of America, Soil Science Society of America, 677 S. Copyright © 2005. Used by permission.


Phosphorus (P), a required nutrient for all livestock, has numerous essential physiological functions in the body that include energy transfer (ATP), structure of bone, teeth, and membranes, and buffering pH changes in the rumen (salivary phosphate). Ruminants use a larger proportion of dietary P than nonruminants because rumen microbes produce phytase, the enzyme that hydrolyzes P from phytate. The majority of P in most grains is in phytate form, a P form largely unavailable to swine and poultry.