Influence of prenatal and continuous postnatal protein-deficient diets on the development of rats

The influence of prenatal and continuous postnatal protein-restricted diet on the development of rats was investigated. Virgin female rats were maintained for 35 days on isocaloric diets containing 8 or 25% casein, and then mated. The animals were supplied their respective diets during gestation and nursing. It was observed that the offspring of mothers kept on the 8% casein diet had 50% less body weight, and 10-15% less brain weight than the corresponding controls. The peak of rapid brain growth for both groups of animals occurred at age 6 days. The rate of de novo biosynthesis of sterols, following the injection of (2-14C)-mevalonic acid into the midline thalamic area and the cerebellum, was also investigated. A significant shift of the age of peaking of 14C-incorporation into sterols in the cerebellum was noted. Our results indicate that although unlimited amounts of food were supplied to the mothers on the 8% casein diet, this could not offset the detrimental effect of the protein deficiency on the offspring.