Effect of the Calcium and Phosphorus Content of the Diet of Chickens on Egg Production and Hatchability

ALTHOUGH many phases of the calcium metabolism of the chicken have been studied, very little attention has been given to the effect of the calcium and phosphorus content of the diet of laying pullets and hens on the production and hatchability of eggs. The purpose of this paper is to present data on this phase of the calcium and phosphorus metabolism of the chicken. These data demonstrate the deleterious effect, hitherto unsuspected, of a high level of calcium intake of laying chickens on the ability of their eggs to hatch, and they suggest that in practical poultry husbandry it is very desirable to control the calcium intake of laying chickens. LITERATURE Wheeler (1919) made many inorganic analyses of the shells of eggs and of the carcasses of chickens and ducks that had received calcium, magnesium, and strontium from several sources as supplements to their diet. He found that the diets . . .