Phosphorus Requirements of Growing Pigs and Effect of Steam Pelleting on Phosphorus Availability

Abstract

The effect of feeding corn-soybean diets containing 0.9% calcium and one of the following levels of total phosphorus, 0.35, 0.44, 0.50 or 0.56% in the form of meal or as pellets has been evaluated using gain and bone development as criteria. Calcium and phosphorus balances for the diets containing the lowest and highest levels of phosphorus have also been carried out. The results showed that phosphorus absorption from the diet containing no added phosphorus was increased from 19 to 29% by steam pelleting, but steam pelleting did not have this effect on the diet containing the highest level of phosphorus. The increased absorbability of the phosphorus in the lowphosphorus diet as a result of steam pelleting was manifested in greater gains and improved bone development. Gain and bone development were improved by phosphate addition to provide 0.5% phosphorus in the diet, but increasing the level beyond this caused no further response. Steam pelleting the diets with adequate phosphorus improved gain and feed efficiency, but this effect could not be explained on the basis of either increased phosphorus availability or increased digestibility of the energy or nitrogen in the diet. Copyright © 1969. American Society of Animal Science. Copyright 1969 by American Society of Animal Science