The importance of hypocalcaemia in the development of hypomagnesaemic tetany

Riddle et al. (1945) and Urist (1959).T h e mean level of diffusible Ca in the plasma during egg-shell calcification is about 8-4 mg/Ioo ml, but in some individuals it may fall to 7-6 mg/Ioo ml, and there is no reason to believe that this latter figure represents a minimum (Taylor & Hertelendy, 1961).It may be claimed with some justification that the laying capacity of a hen is directly related to her ability to absorb and metabolize Ca, and these functions are largely under hormonal control.Nutrition and endocrinology are in fact SO closely interrelated in the Ca metabolism of the laying hen that they cannot be considered separately with any degree of understanding.