Changes in the skeleton during gestation and lactation in the rat

Abstract
Using rats as the exptl. animals, a technique is described for studying changes in. the ends and shafts of the femur and tibia, during pregnancy and lactation. The changes in dry, fat-free weight, of the bones and the percentage ash content were confined to the bone ends. The resorption of the spongiosa which occurred in lactating rats was not observed in non-lactating rats. The rate of replenishment of the depleted spongiosa following lactation was the same whether the animals were then pregnant or not. The shafts of the bones of rats were little affected during lactation.