Uptake of Calcium by the Laying Hen, and Subsequent Transfer from Egg to Chick

THE uptake of calcium by the developing chick embryo and the distribution of calcium therein has been investigated by several groups of workers. However, there is a lack of material available on calcium analysis of whole embryos or newly-hatched chicks divided into many anatomical fractions. The report of Driggers et al. (1951) contains figures for the calcium content of these fractions;—yolk sac, femur, breast bone, brain, heart, liver, proventriculus, breast muscle, and leg muscle, but figures for total calcium content of whole chicks are lacking. Mankin (1929) has reported that mature chick embryos contained an average of 105 mgm. calcium, about 80 mgm. of which was derived from the egg shell, the remainder from the albumen and yolk. Romanoff and Faber (1932) observed that by the seventeenth day of incubation embryos contained 50.5 mgm. calcium, and at date of hatching 116 mgm. Buckner et al. (1926) have reported somewhat …