Fetal survival and neonatal growth with intramuscular injections of folate during gestation in the rat

Folic acid (2.0 mg/ml) was injected subcutaneously to rat dams beginning on day 2 after mating (day 0 = day of sperm in vaginal smear). At parturition litter size per dam and the weight of fetuses were determined. Pups were thereafter equalized among the two groups (n=16 each) and assigned to four dams in each group (n=4 pups per dam). They were weighed every 5 days until day 20. On day 20 pups were killed, dried, and the crude protein levels of carcasses assessed using the Kjeldhal's method. Litter size (7) and weight (6.21) of pups from treated dams were not significantly different from those of control (6.4 and 5.9 respectively, P<0.05). Regression analysis and t-test indicated a faster growth rate and significantly higher crude protein level among pups from treated dams than those of controls. It was concluded that folic acid treatment of dams during gestation and subsequent lactational performance of treated dams may have ameliorated the protein-synthesizing function of cells of neonates from treated dams but further experiments are needed to confirm this conclusion.