Cone and rod photoreceptors in the white-tailed deer Odocoileus virginianus.

Duplicity of the white-tailed deer (Odocoileus virginianus) retina, ie, cone and rod function, was established by histologic and electrophysiologic data. The presence of cones and rods in the deer retina was shown by light and electron microscopy. Electroretinography revealed distinct photopic (bp) and scotopic (bs) components in the b-wave of the electroretinogram that are characteristic of the cone and rod activity. These findings are in contrasts to the popular belief that deer have retina composed entirely of rods.