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Having a dog is one of the most rewarding things you can do. They are loyal, cuddly, comforting friends that bring a lot of happiness into their owner’s lives.
If you are anything like us, then you will love cuddling up with your furry friends, and watching them curl up to sleep by your feet.
You may have been watching your dog sleep, and start to notice that they are sleeping with one eye open, or even if their eyes are fully open when asleep. This can be a little freaky, but usually it is nothing to actually worry about.
Can Dogs Sleep With Their Eyes Open?
Sometimes, you can walk past your dog lying down, and can reach to pet them, thinking that their eyes are open, but you can end up startling them. This is because dogs can often fall asleep with their eyes open!
This is typically no cause for concern, and it is not uncommon for dogs to sleep with one eye open or even both eyes open.
Why Do Dogs Sleep With Eyes Open?
If a dog is sleeping with its eye or both eyes open, it is actually quite normal. Given the fact that even 1 in 5 humans sleep with their eyes open, it is not that unnatural for dogs to do it too.
Most studies say that the reason dogs sleep with eyes open is because it is a natural survival instinct for a lot of species.
If a dog is sleeping with one or two eyes open it is usually a natural survival tactic that will help the animal stay alert and be able to defend itself from predators.
By sleeping with one eye open, it keeps one part of the brain awake, in which case it will be easier to wake up in a fast manner, and be able to ward off attacks or predators.
In addition, sleeping with one eye open can trick intruders or predators into thinking that the ‘sleeping’ dog is awake, alert and ready to defend itself at any given moment.
As dogs are now more docile and not kept in the wild, it is unclear why some species of dog still sleep in this manner, but it is most likely just a trait that has continued on in the breed.
How Do Dogs Sleep With Their Eyes Open?
If a human sleeps with their eyes open, then it can cause a lot of discomfort and dry eyes. However, it is not so bad for dogs as their eyes work differently.
If you have ever looked at your dog’s eyes whilst they are sleeping, and wondered if they are open or closed, you should take a closer look. You will be able to see an extra eye lid that works as a barrier of protection, instead of seeing their immediate eyeball.
This is called a nictitating membrane, which sits behind the dog’s outer eyelid. This membrane works to keep the eyeball clean, clear and protected from any dust or debris when the eyes are shut.
It works like a small film to cover the eyeball when sleeping, which will then retract when the dog opens its eyes fully.
This is why it is never anything to worry about if you notice your dog sleeping with its eyes slightly open, because their actual eyeballs are fully protected from any harm, or dust particles.
Should My Dog Be Sleeping With Its Eyes Open?
Let’s be honest. Dogs sleep a lot. They love to spread out and crash on the sofa, or curl up by the fireplace and make themselves right at home.
So, if your dog is sprawled out and relaxing, you might not be able to see whether they are sound asleep, or just chilling out with you.
Unlike humans, dogs sleep deeply and properly only for about twenty minutes at a time, which means that they can be woken up easily by the slightest of sounds sometimes.
After around twenty minutes to half and hour, they may rouse a little, and move to find a new comfortable spot.
This is probably because wild dogs would have to stay alert in the wild, and be prepared for other animals and predators that may attack at any moment.
If your dog is doing it at home, it does not necessarily mean that they are suffering from anxiety, or that they simply cannot relax.
Sleeping with their eyes open is simply hard wired into your dog’s brain, and they will most likely do it from time to time, or even throughout their entire lives!
It is currently unclear whether sleeping with eyes open is related to dog breed, size, sex or any other factors that may affect their behaviour.
However, some dogs that are bred to have specific facial features can suffer from sleeping with their eyes open far more frequently than others, because their squished faces can make it difficult for them to close their eyes at all!
Some inbred or specific breed dogs such as pugs have been so overbred that the natural shape of their skull has become so misshapen that their eyes will protrude from their eye sockets, making it hard to comfortably close their eyes properly.
If this is the case for your dog, then sleeping with their eyes open can become a cause for concern, or cause some health issues that you will need to keep a close eye on.
In other cases, you may need to take note of your dog’s sleeping habits as it could mean that they are epileptic or even narcoleptic. If a dog is narcoleptic, then they usually sleep with their eyes open because of an abnormal sleeping pattern, or will fall asleep suddenly without warning.
If a dog appears to be asleep, but their eyes are fully open, they may actually be epileptic, and will suffer from seizures from time to time.
If you are concerned that either of these symptoms may be the case, then you should consult a veterinarian and maintain a close watch on your little furry friend’s health.