I’d been wondering different things about dogs and their eyesight lately, for a couple of reasons. We considered that some of the reason Luke seems aggressive with our cat Samantha at times is because he is not recognizing her in low light situations. Also, when Cricket had her recent wellness exam at the vet, it was confirmed she has cataracts just barely starting, which we suspected due to some cloudiness in her eyes. The vet noted that she is probably having difficult seeing, though we’ve seen no sign of that.
My research turned up some different interesting facts about dogs and their eyesight:
- Their eyes consist of the dark center (pupil) surrounded by the iris (colored ring), with the white sclera on the outside of that. All dogs’ eyes are a shade of brown, with some having one or two blue eyes. The muscles that attach to the iris open or close the lens, letting in more or less light.
- The prominent “third eyelid” (nicitating membrane) is in the bottom part of the eye between the lower eyelid and the globe. It offers protection for the eyeball and removes foreign bodies. It is normally concealed beneath their eyelid except in the cases of certain diseases, after general anesthesia, and when there is an eye irritation. I’ve often seen it as well when one of the dogs is falling asleep – has anyone else noticed that? It can be kind of freaky looking!
- Lashes on the upper eyelid also help to keep debris out. Like humans, those lashes seem to be more prominent on some dogs than others. Sheba’s are especially pretty, but harder to see because they are blonde.
- My hubby always told me that dogs could see fine in the dark. I had known that about cats, but not dogs. It turns out he was completely right (yes, I just told my hubby he was right – write that down, honey!).
- Dogs evolved as nocturnal or crepuscular (active at dawn & dusk) predators, which led to them having well-developed night vision and an enhanced ability to detect movement. That does mean that the sharpness of their vision is possibly up to 6 times less than humans’. A larger lens and corneal surface helps with their night vision. Behind the retina is a reflective surface called the tapetum which further enhances their night vision. That reflection is the glow you sometimes see when taking a flash photo of your dog.
- Dogs don’t see the colors that humans see, they most likely only see yellows, blues, and greys.
- The lateral placement of a dogs’ eyes gives them better wide angle vision, but hinders their depth perception and close up viewing. That could be why they say a dog can easily catch a ball moving sideways but maybe not if you throw it directly at their nose. Luke would like to take exception to that thought….we did our own little experiment and he had no trouble catching a ball thrown directly at his nose!
- Cataracts are common in aging dogs. They are caused by a hardening of the lens, just as in humans, and that leads to reduction in vision and nearsightedness. I haven’t seen any sign of that with Cricket. She still catches the ball like a professional, whether it’s thrown near or far.
What I do also notice with all of the dogs is that they see with far more than just their eyes. They use their noses and ears to “see” as well. If Cricket does lose sight of the flying ball, and it hits the fence, she can follow that sound to exactly where the ball is. She also spends much time tracking the ball with her nose. If she loses sight and sound of it, her nose goes right to the ground to track it down.
The best way to care for your dogs’ eyes is probably the same way we care for their overall health:
- Get plenty of exercise, a natural anti-oxidant, which keeps the oxygen moving through their eyes clearing toxins out.
- Provide them with proper nutrition including antioxidants such as Vitamins B, C, E, and beta-carotene; all found in green leafy and colorful vegetables.
- Provide them with proper hydration; the membranes of the eye are susceptible to drying if a dog becomes dehydrated.
What does all of this mean for us, other than being interesting? I feel like it’s unlikely that Luke has trouble seeing Sam at night. I think he just has a tendency to “shoot first and ask questions later” as I often say. He reacts without thinking. He’s been fine with Sam many times, and he often just ignores her when I bring him into the room with her on leash. I think he just wants to play at times; and his play mode can be rough sometimes. We’ll continue to be cautious with them before Sam is given full run of the house though. It could be he’s not seeing her clearly when she’s close up, but by then he should be able to smell her. We will also discuss it with his vet at his next visit, though Luke does not take well to any kind of vet exam, which is another whole issue.
We really don’t see any sign of Cricket having difficulty seeing. There are rare occasions where she’s hunting down the ball and misses it; so maybe. We’ll just keep an eye on her (excuse the pun) for signs of worsening. Surgery for cataracts isn’t always recommended for dogs, but it’s something we want to monitor with our vet.
One thing I do know for sure? The eyes are definitely the window to the soul, and one of my dogs’ most beautiful features.
Do you think your dog sees better with their nose or ears than their eyes?
Most of my research came from this article, and you can read more there as well: Whole Dog Journal: Structure of the Canine Eye.