饲料中不同钙含量对妊娠大鼠钙代谢的影响

目的：研究含钙１．０％、０．２５％和０．０５％三种饲料对妊娠大鼠母体及子代钙代谢的影响。结果与结论：摄食低钙饲料孕鼠的胎鼠数、重量及钙含量与摄食富钙饲料的孕鼠无明显差异，提示孕期低钙摄入对子代体格无明显不良影响。钙代谢试验表明，与１．０％Ｃａ组比较，０．２５％Ｃａ及０．０５％Ｃａ组饲料消耗量明显增加，钙的排出尤其是粪钙的排出明显减少，表明孕体对低钙供给在代谢上存在适应性改变。在０．２５％Ｃａ组，代谢的适应改变使母体钙储量增加，维持机体正钙平衡，但股骨钙量明显低于１．０％Ｃａ组，并有骨钙动员的形态学改变，在０．０５％Ｃａ组，除股骨钙量进一步减少外，母体钙呈负平衡状态，并出现更明显股骨钙动员的形态学体征，表明孕体对低钙的适应性改变有一定限度

EFFECTS OF DIFFERENT LEVELS OF DIETARY CALCIUM ON THE CALCIUM METABOLISM IN PREGNANT RATS

Thirty pregnant rats fed diet containing different levels of calcium(1.0%,0.25%, 0.05% )respectively,till on the 20th pregnant day were executed.The results showed that the low calcium intake had no significantly adverse effect on the fetus.The results of calcium metabolism experiments showed that intakes of diets and apparent absorption rates of calcium of the 0.25%Ca and 0.05%Ca groups rose significantly (P<0.015) compared with 1.0% Ca group,but calcium excretions of feces decreased significantly (P<0.05).It showed an adaptation of the pregnant body on the low calcium intakes.Even though the calcium contents of the maternal femur decreased with the declining dietary calcium levels (P<0.05),there were negative balance of calcium and loss of calcium in the bone in the 0.05%Ca group significantly.It seems that the low calcium intakes during pregnancy would have adverse effect on the maternal bone.