Yes, cats do have an extra eyelid, often referred to as a third eyelid. This extra eyelid is actually a nictitating membrane.
The Nictitating Membrane in Cats
The nictitating membrane is a protective fold of tissue that sits in the corner of a cat's eye, near their nose. It provides additional protection to the cornea. While humans don't typically have a functional nictitating membrane, it is a normal and important anatomical feature in cats.
The eyes of a cat are protected not only by the same types of eyelids that people have, but also by the nictitating membrane, which is sometimes called the third eyelid. This additional eyelid is a whitish pink color, and it is found under the other eyelids in the inside corner of the eye (near the nose).
Key Features of a Cat's Third Eyelid:
- Appearance: It has a whitish-pink color.
- Location: It's located in the inside corner of the eye, near the nose, underneath the other eyelids.
- Function: Provides extra protection for the eye. Typically, it is retracted and not easily visible unless the cat is sleepy, sick, or has an eye problem.
When is the Third Eyelid Visible?
Normally, the third eyelid is retracted and mostly hidden. You might see it briefly when your cat is:
- Sleeping
- Blinking slowly
- Grooming
- Unwell
Potential Health Concerns
If the third eyelid is consistently visible in one or both eyes, it could indicate a health issue such as:
- Dehydration
- Weight loss
- Underlying illness
- Eye irritation
If you notice your cat's third eyelid is consistently visible, it is important to consult with a veterinarian to rule out any underlying medical conditions.
