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Dog's Third Eyelid - Nictitating Membrane - Cherry Eye

Updated: May 27, 2022

Did you know dogs have a third eyelid?

The Mysterious and Interesting Dogs Third Eyelid.

If you're like most people, you probably don't know much about your dog's third eyelid. This mysterious structure is actually quite interesting and plays an important role in your dog's health. Let's take a closer look at the dog's third eyelid and learn more about its function and anatomy.

The third eyelid, or nictitating membrane, is a thin layer of tissue that covers the inner corner of your dog's eye. This structure is actually part of the conjunctiva, which is the clear membrane that covers the white part of your dog's eye.

The third eyelid contains a small gland called the Harderian gland, which produces tears and helps keep the eye lubricated.

The main function of the third eyelid is to protect your dog's eyes from debris, dirt, and other foreign objects. It also helps to keep the eye moist and lubricated.

When your dog's eyes are irritated or inflamed, you may notice that the third eyelid pops up in order to help soothe and protect the eye. This is commonly known as Cherry Eye.

While the third eyelid is mostly hidden from view, you may be able to see it peeking out when your dog's eyes are closed. If you notice that your dog's third eyelid is popping up more frequently or that it seems to be bothering your dog, it's important to take him to the vet for an examination. In some cases, the third eyelid may be a sign of an underlying health condition.

An example of cherry eye in a dog

So, there you have it! Now you know a little bit more about the mysterious and interesting dog's third eyelid. This important structure plays a vital role in your dog's health, so it's good to be aware of it.

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