Gender differences in visual discrimination by rats in response to malnutrition of varying durations

Visual discrimination of hooded rats was tested at 3 months of age by a Lashley procedure. Three groups of rats were used: those with histories of protein deprivation for up to 20 generations, those with protein deprivation for a single generation, and well-nourished controls. Growth retardation was present to a similar degree in both genders of the 2 malnourished groups. Deficits in visual discrimination were observed in female animals with intergenerational malnutrition, but not in females with single-generation malnutrition. Males with intergenerational and single-generation malnutrition showed equal deficits in visual discrimination. These findings demonstrate that the performance of female rats is impaired only after prolonged exposure to malnutrition, whereas males are vulnerable after shorter periods.