Influence of Dietary calcium and Phosphorus Levels on the Performance and Bone Characteristics of Growing-Finishing Swine

Abstract
Eighty-four purebred Yorkshire pigs weighing 27 kg initially were used to determine the calcium requirement of growing-finishing pigs fed two levels of phosphorus. The basal diets were modified by the addition of ground limestone to provide calcium levels of 0.15, 0.30, 0.45, 0.60, 0.75 and 0.90% of the diet and by the addition of phosphoric acid to provide phosphorus levels of 0.45 and 0.65% of the diet. All pigs had received a diet containing 0.80% calcium and 0.65% phosphorus prior to being allotted to treatment. The calcium requirement of growing-finishing swine from 27 to 91 kg was approximately 0.30% of the diet for maximum gain and feed efficiency. On the other hand, the level of dietary calcium required to maximize skeletal development was approximately 0.60% of the diet, but the change in the levels of ash, calcium and phosphorus in the metacarpal and turbiriate bones were fairly small when the level of dietary calcium was increased from 0.30 to 0.60%. The phosphorus requirement of swine from 27 to 91 kg was 0.45% or less for maximum gain and feed efficiency as well as for maximum skeletal development. Dietary calcium and phosphorus levels did not affect the gross visual symptoms of turbinate atrophy in the pigs. Dietary calcium levels did not influence the incidence of lameness in pigs from 27 to 91 kg live weight, but it tended to be slightly greater in pigs fed diets containing 0.45% phosphorus compared to pigs fed the diets containing 0.65% phosphorus. Copyright © 1973. American Society of Animal Science . Copyright 1973 by American Society of Animal Science.