The Effect of Variation in the Calcium-to-Phosphorus Ratio on the Utilization of Nitrogen, Calcium, and Phosphorus by the Growing Chick

1. Three groups totaling 123 chicks were fed accurately known amounts of rations containing 0.9, 1.5, and 2.3 per cent of calcium with liberal provision of the antirachitic factor so that conditions for assimilation and deposition were favorable. 2. By means of the comparative slaughter test the retention of ingested nitrogen was found to be about 37 per cent, and that of phosphorus about 28 per cent in the three lots. 3. With 0.9 per cent calcium in the ration, 35 per cent of that ingested was retained; at a level of 1.5 per cent calcium, 24 per cent was retained, while with 2.3 per cent of calcium ingested but 13 per cent was retained