Can the third eye lid being visible in cats be a sign of old age?

No, the third eyelid (also called the nictitating membrane) being visible in cats is not a sign of old age. It's a normal anatomical feature in cats and is present throughout their lives.

Here's why:

* Purpose: The third eyelid is a protective membrane that helps to keep the eye lubricated and shielded from debris. It can also act as a barrier to protect the eye from injury during rough play or while navigating tight spaces.

* Visibility: The third eyelid normally retracts into the corner of the eye and isn't visible unless the cat is stressed, tired, or has an underlying eye condition.

* Other reasons for visibility: While not a sign of old age, the third eyelid might become more prominent due to:

* Dehydration: This can cause the eye to sink back slightly, making the membrane more noticeable.

* Eye irritation: Inflammation or infection can trigger the third eyelid to protrude.

* Underlying health problems: Certain health issues, like uveitis (inflammation of the middle layer of the eye), can also lead to a more visible third eyelid.

If you notice your cat's third eyelid is consistently visible, it's important to take them to a veterinarian for a check-up. They can assess the cause and determine if any treatment is necessary.