Abstract
SUMMARY: The available data on calcium, phosphorus and carbonate balance experiments with laying and non-laying birds have been collected and condensed. From this condensed data the following relationships have been derived:(1) Calcium excretion is a function of calcium intake.(2) Phosphorus excretion is a function of phosphorus intake.(3) Carbonate excretion is a function of carbonate intake.(4) Carbonate/calcium ratio of the excreta is a function of carbonate/calcium ratio of the intake.(5) Calcium/phosphorus ratio of the excreta is a function of calcium/phosphorus ratio of the intake.