Removal of Calcium from Uterine Blood During Shell Formation in the Chicken

THE uterus or shell-gland has long been known to be that part of the oviduct responsible for shell formation. In all but two of the reports of the effect of shell formation on various plasma constituents, blood samples were obtained from a brachial vein or the heart and not from a uterine blood vessel. Blood obtained from a source other than a uterine vein will not necessarily reflect changes that occur in the uterus. Venous blood from the uterus flows into the left renal vein, is mixed with blood from the kidneys and renal portal system, and flows into the posterior vena cava (Stresemann, 1928; Hunsaker, 1959). Here the blood is further mixed with venous blood from the abdominal area and lower limbs. Changes in arterial blood during its passage through the uterus can be detected only by comparing the composition of the blood entering and leaving the organ. There…