Effect of Severe Undernutrition in Early Life on Growth, Brain Size and Composition in Adult Rats

Abstract

A study was undertaken to determine the effect of varying periods of undernutrition in postnatal life on the size and chemical composition of the brain in rehabilitated adult animals. Four groups of male albino rats were drawn from litters of 16 pups nursed by an undernourished dam. One group was weaned at 3 weeks to a diet of 18% casein. Three similar groups were fed a 3% protein diet until 5, 7 and 9 weeks of age. A diet of 18% protein was then fed until the rats were 19 weeks old. The growth, and brain size and composition of these nutritionally deprived groups were compared with those of littermates adequately nourished from birth. Undernutrition during suckling caused a degree of stunting of body size that was only partially reversed by nutritional rehabilitation. Brain size and brain DNA were depressed by undernutrition in the preweaning period but were not affected further by deprivation in the post-weaning period. They did not respond to an adequate diet. Brain size was less affected than total body size. Cholesterol levels of brain were significantly and irreversibly depressed if undernutrition occurred through 5 weeks of age but responded to earlier rehabilitation. Phospholipid phosphorus and RNA content of brain were similar in all groups. The chemical composition of the smaller brains of the deprived animals was not significantly different on the basis of percentage composition than that of the larger brains of the well-nourished animals.