A study was carried out in Wistar female rats to determine the influence of maternal preconceptional undernutrition on fetal growth and maternal-fetal exchange of energy and nitrogen retained by pregnant rats, with and without supplementary feeding, in comparison to a control group. Experimental malnourished female rats and controls of similar weight, were mated for a single period of 24 hours. From the first day of gestation one group of malnourished and one group of the control rats were fed for 20 days a casein diet with NDpCal% 12, and the other group of malnourished and control pregnant rats were fed NDpCal% 4 during 20 days. At the end of the trials rats were sacrificed: nitrogen, fat and energy values of samples of extracted fat and portions of dried fat-free in the maternal carcass and uterine contents were determined. Both malnourished groups fed during pregnancy with NDpCal% 12 or 4, utilized nitrogen and energy more efficiently, but failed to reach the body weight of the pregnant control rats fed with NDpCAl% 12 or 4, respectively. Food supplementation of the malnourished group during gestation allowed the maternal carcass to catch up growth. The litter size, however, remained diminished, fetal growth improved poorly and the uterine content weight attained only 45% of the maximum of the controls fed on NDpCal% 12. These results showed that when supplementation was imposed only during pregnancy, the recovery of maternal tissue was prioritary, while nutrition of the fetus was secondary.
Animals Dietary Proteins