Calcium deficiency, pregnancy and lactation in rats

Adult female rats were subjected to severe calcium deprivation by feeding them a calcium-deficient diet containing oxalate (Test group a), and in addition by subjecting some of them to pregnancy and lactation (Test group b). The mandibles were collected for determination of ash and cortical bone area.

The ash content of the mandible was reduced in both test groups, but the additional effect of pregnancy and lactation was less than that previously found in long bones. Planimetric analysis revealed that bone removal had not occurred from the periosteal surfaces of the mandible. Most of the bone loss had taken place by resorption from its endosteal surfaces.