Calcium Phosphate Deposits in Guinea Pigs and the Phosphorus Content of the Diet

Abstract

Approximately 90% of the guinea pigs that consumed a synthetic diet which contained 0.8% of calcium and 0.9% of phosphorus developed visible deposits of calcium phosphate. If the total amount of phosphorus was reduced to 0.5%, the incidence of the deposits was less than 10%. The Ca:P ratio may be as important as the absolute amounts. When animals consumed the high-phosphorus diet they grew more slowly and the survival period was shortened. The soft tissues contained an abnormally high percentage of mineral constituents. Under the experimental conditions described wrist soreness and wrist stiffness invariably preceded the appearance of visible calcium phosphate deposits.