What colors can dogs see? The answer to this question is (literally and figuratively) not simply black and white. Dogs’ eyes use color-detecting cells called cones. Like most mammals and colorblind humans, their eyes contain two kinds of these cones (versus three in the normal human eye). The brain interprets the neurons’ excitement in reaction to yellow light detected in the cone cells as the color yellow. Similarly, it understands the neurons’ suppression in response to blue light detected in the cone cells as the color blue. However, dogs’ neurons have a neutral reaction to both red and green light. If we assume that dogs’ brains interpret color in a similar manner as the brains of colorblind people, dogs see primarily in gray, blue, and yellow.
Potential eye and vision problems in dogs range dramatically in type and severity, from conjunctivitis (an inflammation of the lining tissue) to cataracts (cloudiness of the crystalline lens of the eye) and even glaucoma (a condition of high pressure in the eye which can progress to blindness.) Your best bet is to keep an eye out for any kind of irritation in your dog’s eyes or different behaviors, such as squinting, and get them checked out by a vet as soon as possible.
Coren, Stanley. “Can Dogs See Colors?” Psychology Today. 20 October 2008. Web. 24 February 2014. <http://www.psychologytoday.com/blog/canine-corner/200810/can-dogs-see-colors>
“Eye Care for Dogs.” WebMD. Web. 24 February 2014. <http://pets.webmd.com/dogs/guide/eye-care-dogs>
Wolchover, Natalie. “How Dogs See the World.” 26 June 2012. Web. 24 February 2014. <http://www.livescience.com/34029-dog-color-vision.html>