Effects of Food Restriction in Rats during Pregnancy and Lactation on the Maternal Body and Growth of Progeny

Abstract

The effects of food restriction during pregnancy and lactation on the rat maternal body and growth of progeny were studied. We prepared four groups of pregnant rats : two groups fed ad libitum (20% casein diet [C] and 20% soy protein isolate (SPI) diet [S]) and two feed-restricted groups (casein diet [CR] and SPI diet [SR] at 30% less than the quantity fed to the ad libitum groups during pregnancy and lactation). The feed-restricted and ad libitum-fed animals were pair-fed. Food restriction during pregnancy resulted in the maternal body weight gain being significantly smaller in the CR and SR groups than in the C and S groups, respectively. The body weight and organ weight of newborn pups in the SR group were also significantly lower than those of the S group. Food restriction during pregnancy and lactation also significantly reduced the maternal body weight and organ weight of the CR and SR groups when compared with the C and S groups, respectively. At 3 weeks after birth, retarded growth was observed in the weaning progeny of the CR and SR groups in comparison with the C and S groups, and in the progeny of the S and SR groups in comparison with the C and CR groups, respectively. We conclude that the food restriction through pregnancy and lactation markedly affected the maternal body and growth of the progeny. Retarded growth was also apparent in the weaning progeny of the SPI diet groups when compared with the casein diet groups, whether food-restricted or not.