Probably not what you’ve ever seen, because if your cat is healthy will not be visible, but cats as well as the eyelids that open and close, have a third eyelid, called the nictitating membrane whose primary function is to protect the animal’s eyes.
Cat third eyelid functionThis third eyelid is a membrane that is located on the corner of the eye, and has a gland that allows the cat’s eye is always well lubricated. As we said, not usually visible, and is usually the one who controls your state veterinarian when you press gently on the cat eye, at which time it becomes visible in the corner of the eye.
The main functions of the third eyelid is also lubricate the eye, protect it from external aggression and help remove foreign bodies that may have been introduced into the animal’s eye.
When the third eyelid is visible, it means that your cat has an eye problem such as an ulcer, inflammation or injury. This is because, in these cases, external eyelids tighten and cause the appearance of the eyelid that covers the eye partially or totally, to allow healing and prevent it from getting worse.