Abstract
An animal experiment has been performed to measure the effects of calcium deficiency and its later replenishment on growth and bone development of the young animal, and to see if there was any age difference. A diet deficient in calcium was fed to the young rats for 30 days at one of the three stages of growth, and then the diet was switched over to a stock diet containing the minimum requirement of calcium, which was fed till the 90th day after weaning. The body and bone lengths were not affected by the calcium deficiency, but the effect on weight growth was greater on the younger. The effect on ash, calcium, and phosphorus contents of the bone was more remarkable than that on the body weight, but with little age difference. The calcium replenishment resulted in an appreciable recovery of both body weight and bone development in the early and late deprivation groups, but not in the group of middle stage deprivation.
