Dear Dr. Cox,

I was wondering if my boxer “Josie” can see colors. My neighbor told me that dogs are color blind.

Stephanie from Issaquah

Light

As compared to humans, dogs and cats have a much greater light sensitivity. This is related to the presence of a tapetum and a retina dominated by rod photoreceptors. Dog and cat light sensitivity is reported to exceed humans by 5-7 times and the tapetum to reflect over 100 times the light of the human fundus.

Motion

Motion sensitivity in animals is enhanced in dim light and in the peripheral retina. It has been demonstrated that dogs detect moving objects at a distance that exceeds that of the same object when stationary.

Flickering Lights

Have you ever seen your computer screen on a video? It appears to be flickering and not legible. Is this how your television appears to your dog? Most likely…Since TVs are updated at 60 times per second and the dog threshold for retinal recovery is limited to approximately 70 times per second, the TV looks to be flickering rather than smooth.

Visual Perspective

Go out into the backyard and lay on your stomach. Look around and see the world through the eyes of a Dachshund. Get up on all fours and become a Great Dane. The visual perspective of animals is varied depending on height of the eye from the ground.

Visual Field of View

Depending on the length of the nose and forward placement of the eyes the visual field will vary. Visual field is the amount of area seen when the eyes are fixed on a single point. In general humans have a 180 visual field while in dogs and cats it varies from 200-240 degrees.

Color Vision

The perception of color is difficult to answer. Dogs do possess two main types of cone photoreceptors. One that is sensitive in the yellow-green spectrum and the other in the blue-violet spectrum. Other color wavelengths are likely perceived as shades of grey.

Summary

Vision in dogs and cats is developed to suit their needs. Motion detection and dim light vision being more important than color vision and high visual acuity.

Kevin Cox, DVM

Redmond-Fall City Animal Hospital