ARE ALBINO-RATS NIGHT BLIND

Based on single-unit recordings from the superior colliculus and optic nerve, albino rats recently were reported to have dark-adapted thresholds that are 2 log units higher than those of pigmented rats. To confirm this result, electroretinograms (ERG) were recorded with pupillary light reflex thresholds from the same strains of albino (CD) and pigmented (Long-Evans hooded) rats. Neither ERG nor pupil measurements showed higher dark-adapted thresholds for albino relative to pigmented animals. Both groups had dark-adapted thresholds close to the thresholds found for hooded animals in the reported study. These experiments measuring ERGs and pupillary light reflexes do not verify the report of night blindness in albino rats.