CALCIUM ABSORPTION AND VITAMIN D

Abstract

The rate at which Ca45 given as an oral dose appears in blood and bone of chicks is markedly affected by vitamin D. Absorption of Ca45 from an intramuscular dose is not influenced by either vitamin D or the Ca content of the diet. The interaction of the amount of Ca45 in the oral dose and vitamin D on the amount of Ca absorbed indicated that the vitamin D effect on the absorption is a function of the quantity of Ca presented for absorption. Absorption experiments carried out with chicks which were fed diets of varying Ca content showed that vitamin D enabled the chicks to adapt the capacity to absorb Ca to different dietary intakes of Ca.