The effects of pregnancy and lactation on dietary self-selection in the rat.

Total food intake and intake of discrete dietary components, carbohydrate, fats, and protein, throughout pregnancy and lactation were measured in the albino rat, with virginal rats acting as controls. The dietary components were isocaloric and presented in a self-selection situation. Although the reproductive subjects ate more carbohydrate, protein, and total food than controls during the lactation phase, their intake did not significantly exceed that of controls during pregnancy. In addition, reproductive but not virginal animals changed patterns of selection over the reproductive periods. They consumed more total food during gestation and lactation, and more carbohydrate and protein during lactation.