The influence of early nutrition on the development and myelination of the brain

Abstract

The rate of growth of suckling rats can be greatly influenced by adjusting the size of the litter at birth. Even though ad lib. feeding be allowed after weaning at 21 days, the smaller rats from large litters become smaller adults than those whose development has been unrestricted in the suckling period. In rats the brain grows most actively and becomes myelinated during the second and third weeks of post-natal life while the animal is still suckling. Widdowson & McCance (i960), however, did not find that the weight of the brain was much affected by varying the plane of nutrition at this time. The experimental design of the previous authors was followed, and it was confirmed that varying the litter size during lactation made relatively little difference to the wet weight of the brain. There were, however, much larger differences in the rate of cholesterol deposition in the brain, and these were obtained with quite small alterations of body weight.