You may be under the impression that dogs only see in black and white, however this is a common misconception. While a dogs’ strongest senses are hearing and smell rather than sight. They can still see colors, just not the same way we do. In addition, their vision varies from breed to breed. But what do you need to know about your dog’s vision?
Dogs have 20/75 vision. This implies that they need to be 20 feet away from an object to see it and a person 75 feet away. Some breeds have sharper eyesight. Because they are bred for better vision, labradors are frequently used as seeing-eye dogs and might have a vision closer to 20/20.
What Eye Colors Can a Dog Have?
The eyes of most dogs are various tones of brown. However, dogs can also have eyes that are nearly any other color. There’s a good chance you’ve seen huskies with blue eyes or even a pair of blue and brown eyes, a condition called heterochromia. Dogs can have green or hazel eyes, though they are less common. As puppies age, their eyes may change color, like humans.
How Similar Are Human and Dog Eyes?
In contrast to the occasionally striking differences between human and other animal eyes, a dog’s eyes appear eerily similar to ours, right down to the pupil shape and iris colors, and they can express emotion with just a simple lift of the brow. There’s a reason for this, though.
Human and canine eyes are structurally very similar. Like a camera, our eyes capture light and transform it into visual images. We have rounded, black pupils surrounded by colored irises that control how much light enters the eye. The retina, the tissue lining the eye, receives the light from the pupil and iris and transmits it through the lens to the retina. The retina processes the light and converts it into an image, which the brain interprets.
However, there are many notable differences between our perspectives on the world and those of our dogs, all of which reveal something about the nature of dogs before they joined us around the fire thousands of years ago and as we have evolved together.
The Anatomy of a Dog’s Eye
Dogs have three eyelids, not just the standard two. A third lid, known as a nictitating membrane or a haw, which moves horizontally across the eye from the inside corner, is present in dogs in addition to their two blinking eyelids, just like in humans.
In addition to allowing your dog to see, the haw has evolved to serve three functions:
- Keeping the eye moist
- Preventing corneal scratches from dust and other physical impurities
- Supporting immune system health
The fact that dogs are so low to the ground makes it more dangerous for their eyes than for people to walk through grass and other vegetation.
Where is the third eyelid? The membrane is relatively noticeable in some dog breeds, such as hounds, spaniels, and other droopy-eyed puppies, so dog owners who live with these animals are probably already aware that dogs have them. However, in most dogs, you can only see a tiny portion of the membrane at the inner corner of the eye. When a dog is asleep or under anesthesia, you may occasionally notice the membrane beginning to pull across the eye.
How Good Are Dogs’ Eyesight?
We have dogs beat when it comes to visual acuity, although dogs can easily outsmell and outhear humans. Humans typically have 20/20 vision at their best, which enables them to see objects of a specific size clearly from a distance of 20 feet away. Experts believe that many dogs have 20/75 vision, meaning they must be 20 feet away from an object to see it with the same accuracy as a human can at 75 feet, although visual acuity can vary by breed.
Are Dogs Nearsighted or Farsighted?
Dogs are typically neither nearsighted nor farsighted, so they need help seeing objects farther away. However, some research suggests that breeds, such as Rottweilers, German shepherds, and miniature Schnauzers, are more prone to poor vision. Additionally, one study discovered that their nearsightedness might worsen as dog’s age.
Do Dogs Have the Ability to See Color?
Despite what many people think, dogs do not see only in black and white. They can see color but fewer shades than we are. So life isn’t exactly a riot of color, but they aren’t wandering around in a perplexing landscape of shades of gray either.
Unlike humans, dogs have fewer cone cells, photoreceptors that enable mammals to perceive color. Dogs see only yellow and blue because they have only two types of cones, whereas humans have three types, making them similar to humans who are colorblind to red and green. There are so many dull browns, grays, yellows, and blues in the world that it’s hard to tell that bright red toy from your hardwood floors.
Dogs can accurately perceive their surroundings, even without color, using other sensory cues like smell, texture, and sound. Given how much information their olfactory system processes, it’s likely that you’ve heard that dogs see with their noses.
However, there are many significant areas where dog vision surpasses human vision.
Humans are undoubtedly nocturnal beings. During the day, we go about our daily lives, eating, working, and moving in the sunlight. On the other hand, dogs descended from wolves, who hunted and moved primarily at dawn, dusk, and night, necessitating the ability to see in dim or no-light conditions. As a result, dogs’ eyes reflect this ancestry.
Dogs not only have more rods, the photoreceptors that allow mammals to see in the dark, but they also developed the tapetum lucidum, a reflective layer behind the retina that functions as a mirror at night to increase light sensitivity. Dogs’ eyes shine in photos or at night because of this layer.
Field of Vision
Because dogs’ eyes sit relatively wide on their skulls compared to humans, dogs have more expansive vision fields than humans. The range of a dog’s field of vision varies depending on breed, and it is between 240 and 270 degrees (compared to our 180-degree field of vision). Because of this, they can see more of their surroundings without turning their heads, making hunting and keeping an eye out for danger easier.
However, a better field of vision comes at the expense of depth perception, which aids jumping and catching. As a result, many dogs struggle to catch treats or toys that are thrown close to them.
Considering all these variations together may seem strange: an expansive, somewhat hazy, dull field of vision doesn’t exactly seem like the best evolutionary path for these vital organs. But that doesn’t cover everything.
How Dogs Communicate Through Their Eyes
We cannot simply converse with our dogs, which is one of life’s great injustices. However, dogs can effectively communicate with their two-legged friends using body language, verbal communication, such as barking, and eye contact.
Expressing Feelings With a Glance
In contrast to their wild cousins, dogs have evolved more expressive facial features over their 30,000+ years by our side, giving them the uncanny ability to convey complex emotions with just a lift of the brow.
Recent studies have revealed that, in contrast to wolves, dogs have a set of muscles around their eyes that enable them to express human emotions like sadness, uncertainty, defiance, and others. A muscle called the Retractor Anguli Oculi Lateralis (RAOL) pulls the eyelid towards the ear, emphasizing the enlarged appearance of the eye. In contrast, the Levator Anguli Oculi Medialis (LAOM) lifts the inner eyebrow to enlarge the appearance of the eye and make dogs appear almost baby-like. All dogs possess the RAOL muscle, and all dogs, aside from Siberian huskies, possess the LAOM muscle which make their puppy dog eyes slightly less prominent.
Dogs are thought to have developed these muscles to interact with and control their human companions, essentially taking advantage of their cuteness. This is your dog’s way of saying please or expressing a need or want.
If you’ve ever experienced puppy-dog eyes, you are aware of how effective they are at getting a dog to do what it wants, whether it be a bite of your food, a softer expression when they’ve done something wrong, or a stroll outside.
Is Dog Eye Contact a Sign of Bonding or a Threat?
Dogs can use staring to communicate danger, show respect for people or other dogs, or even form bonds with their human family members. Their intent will vary depending on the situation, including who is staring, their body language, and the prevailing atmosphere.
Make eye contact with the owner of the dog. According to a 2015 study, eye contact between owners and their dogs fosters feelings of love and bonding by raising oxytocin levels. Even parent-infant bonding has been used as a comparison by researchers.
But eye contact is only sometimes a good thing. Staring is a relatively high level of aggression on the canine aggression scale and can be a sign of stress or anxiety. Prolonged eye contact may also be interpreted as a sign of dominance or a threat depending on how your dog was raised.
Finally, even though it may seem funny, if you ever see your dog giving the whale eye or the side eye, which is another sign of discomfort, take it as a sign to assist them in finding comfort or removing themselves from the situation they are currently in.
How Can You Tell If Your Dog’s Eyes are in Good Condition?
Your dog’s eyes can reveal underlying health issues based on color, shape, and moisture content.
Similar to humans, your dog’s eyes can reveal a lot with a glance. Are they hazy or clear? The eyes’ whites appear to be red, but are they white? Does moisture make them shine? Are there any discharges or alterations in color? Are your dog’s eyes being pawed at? They could all be symptoms of canine eye conditions that are common.
Common Dog Vision Issues
Just like humans, dogs can also be afflicted with vision issues or eye-related problems.
A cataract is a medical condition in which the eye lens gradually darkens. Cataracts are visible as thick, white spots in the center of the eye, which can impair vision and even result in blind spots. Cataracts are distinct from age-related eye clouding that typically has a blue tint in dogs. If they are severe enough, your dog’s doctor may advise surgery to remove the tissue and improve their vision. In addition to being frequently inherited, cataracts can result from eye trauma or other underlying eye conditions. Diabetes and cataracts have a connection. This is just one of the many benefits of maintaining a healthy weight and lean physique for your dog.
Certain dog breeds have weaker muscle fibers that connect the nictitating membrane, or haw, to the rest of the eye. The tear-producing gland, a part of the haw, may prolapse and become visible at the inner corner of the eye when those muscle fibers fail. Surgery is an option to fix it. Your vet will be able to explain whether using eye drops is a viable option and provide more information on how to make your dog more comfortable in the meantime.
Pink eye is more commonly referred to as conjunctivitis, an inflammation or infection of the conjunctiva, the tissue that lines the eyelids, including the third eyelid and loops back over the eye to protect the sclera or the white part of the eye.
Corneal Scratch or Ulcer
Like humans, dogs can scratch their corneas, the transparent layer covering the outside of the eye. This can result in mild discomfort, tearing, or even a milky, pus-like discharge. If left untreated, ulcers can result in infection, permanent damage, vision loss, and need to remove the affected eye. Veterinary medicine is typically used to treat ulcers.
Dry eyes, most frequently characterized by redness, excessive blinking, and even a yellowish mucosal discharge, are not just uncomfortable for your dog. If your dog isn’t producing enough tears, there may be more severe issues, like recurrent corneal ulcers and irreversible vision loss. Regular use of lubricating eye ointment is typically used to treat dry eyes.
A dangerous rise in eye pressure caused by glaucoma is characterized by watery discharge, redness, protruding or enlarged eyes, and even lethargy. Pain and blindness are possible side effects of glaucoma, which can harm and possibly destroy the retina. Glaucoma can have a genetic component or be brought on by unrelated conditions like tumors behind the eyes or scar tissue buildup from recurrent infections. A veterinarian will recommend medication that encourages fluid drainage and lowers eye pressure to treat glaucoma to stop it from worsening and causing severe damage. When the condition is advanced or acute, or when your dog is in excruciating pain, it might be necessary to remove the affected eye.
Tear stains are brown or reddish spots that appear beneath your dog’s eyes. They are more evident in dogs with white coats. These marks occur when a dog produces too many tears or is unable to drain their tears effectively using standard methods. They are caused by porphyrins, excreted through a dog’s body through saliva, urine, and tears. Various factors, including poor diet, allergies, eye irritation, and genetics, can bring on tear stains.
How to Keep Your Dog’s Eyes Healthy
Dogs are predisposed to eye injuries and infections due to the canine lifestyle, but there are some preventative measures that pet owners can take. Maintaining a routine for your dog’s eye care can help you stay on top of any problems before they worsen. There are steps you can take to help keep their eyes as healthy as possible, even though you can’t always stop eye injuries from happening.
Regular eye exams performed as part of a wellness examination by your veterinarian can help identify eye issues before symptoms emerge or even before you become aware of them.
Trim Their Hair
If the fur around your dog’s eyes becomes too long, it may irritate them, so regular grooming can help prevent this.
Trim Their Nails
Keeping their nails short will make your dog less likely to paw at their face and scratch their eye. Regular nail trimming is crucial for dogs whose nails don’t wear down naturally.
Feed Your Dog Healthily To Maintain Eye Health
Diet is a crucial component of a dog’s eye care.
To be clear, dogs have no one-size-fits-all diet; not all dogs can afford the luxury of a fresh and raw diet. Every dog has different dietary requirements, and the cheapest kibble is far less risky than a homemade diet that needs to be prepared appropriately. Therefore, speaking with a veterinary nutritionist before feeding your dog raw meat is crucial.
Regularly Look into Their Eyes
Examining your dog’s eyes closed regularly will help you spot any changes; look out for indications of redness, cloudiness, or tearing. Be sure to contact the veterinarian right away if you have any concerns.
Eye conditions can negatively impact your dog’s health and quality of life. The good news is that with early detection and diagnosis, virtually all eye conditions can be treated with high success rates. Regular observations, checks, and veterinary health exams are essential to maintain the quality of your pet’s vision and to keep them comfortable.