Behavioral and physiological effects of early handling and early malnutrition in rats.

This experiment employed a 2 x 2 design in which the nutritional and early stimulation conditions of rat pups were manipulated during the 1st 3 weeks of postnatal life. Animals were observed in various open field activities at 22, 23, 29, 36, and 50 days of age, and killed at 55 days of age for neurochemical analysis. Early handling decreased the behavioral differences due to malnutrition and resulted in fewer, but larger cells in rat forebrain for both well-nourished and malnourished groups.