Effects of protein-calorie deficiencies on the learning ability of the wistar rat

Abstract

The present experiment employed the deprivation model. The treatment conditions were defined by the severity of protein-calorie deficiencies and the growth-developmental period at which such deficiencies were imposed. Prenatal and neonatal deficiencies were imposed by maintaining the mothers on the diets during pregnancy or lactation. Early deficiency was accomplished by maintaining weaned pups on their respective diets from 21–42 days of age. After realimentation on an adequate diet, the experimental animals were tested in three water mazes. Protein-calorie deficiencies did not cause permanent reduction in body weight, but neonatal deficiencies were found to impair the learning of the most difficult maze. These and other findings were discussed in the context of physiological changes which might accompany protein deficiencies, and it was concluded that the permanence of the effects on learning ability was related to the period of growth and development at which the deficiencies occur, the severity of the deficiencies, and the difficulty of the learning task.