Date of this Version
An experiment was conducted to determine the effects of a low phytate, nutrient dense corn variety on pig performance, fecal phosphorus and fecal nitrogen. Experimental treatments were: 1) corn-soybean meal diets formulated with purchased yellow corn; 2) similar diets formulated with 500 FTU/kg phytase; 3) diets formulated with a nutrient dense corn variety having a reduced phytic acid, elevated lysine, and higher energy compared to yellow corn; and 4) diets formulated with the nutrient dense corn variety and phytase at 500 FTU/kg to 130 lb BW and blended with yellow corn thereafter based on estimated available phosphorus. There was no difference in daily gain or daily feed for pigs fed the normal yellow corn diets with or without phytase. However, when phytase was added to the nutrient dense corn from arrival to 130 lb and the estimated available phosphorus was balanced by blending normal yellow corn and the nutrient dense corn from 130 lb to slaughter, daily gain and daily feed intake were reduced. Phosphate in the feces was reduced for all diets compared to the yellow corn diet without phytase. However, nitrogen was increased in the feces from pigs fed diets containing the nutrient dense corn due to its higher crude protein compared to yellow corn. These results suggest that when diets are formulated on an equal lysine, energy and available phosphorus basis, pigs have similar performance for diets formulated with yellow corn, yellow corn plus phytase and a nutrient dense corn variety. However, these results do not support blending of yellow corn and the nutrient dense variety based on available phosphorus content. Further research is warranted to determine the cause for the depression in daily gain and daily feed reported for this treatment.