Alkaline Phosphatase and Egg Formation

Abstract

THE deposition of calcium carbonate in the egg shell is a significant phase of calcium metabolism in laying hens, but the physiology of this process is not yet understood. Warren and Scott (1935) determined the time spent by the egg in the various sections of the oviduct and found that it remains in the uterus (shell gland) and vagina 20 hours and 40 minutes. Burmester, Scott, and Card (1939) presented evidence that “the rate of calcium carbonate deposition is relatively slow during the first 3 hours. The rate then increases and quickly assumes a constant figure which is maintained until the twentieth hour or the time of laying.” This rate is expressed by the equation: y = 5.644x — 16.617 in which y is the percentage of calcium carbonate deposition and x the number of hours in the uterus. These important observations on the constancy of the curve of the curve . . .