Effects of fasting during gestation on brain development in BALB/c mice

The development of the corpus callosum (CC) was examined in BALB/cCF mice in relation to the effects of a 32-h period of maternal fasting. The treatment was imposed on days 15 and 16 during gestation, which immediately precedes the time when the initial callosal axons cross the midline. The BALB/c strain was used because it is prone to developing a corpus callosum which is either small in size or absent at the midline. A split-litter design was used where fetal brain development was assessed on days 22 and 50 postconception (birth and weaning). The treatment did not increase the incidence of absent CC. On day 22 the midsagittal cross-sectional area of the CC, as well as brain and body weight, were smaller in the experimental group. Covariance analysis showed the effect on brain weight to be related to the overall growth retardation seen in the low body weight. In the control group, CC area and the brain weight were positively correlated, but in the experimental group this was not the case, suggesting the effect on the CC was independent of growth retardation. By day 50 there were no significant differences between the groups on any measure, although the data did show a trend toward a smaller CC in the fasted animals.