why do cats have a third eyelid?

by Verena
(Beijing, China)

Hi,

I'm just wondering why cats have two eyelids(is what it looks like to me)? I notice that whenever my kitten closes her eyes to go to sleep, there's another thin grey eyelid(or if there's a real name for it) that closes before it too. Dogs have it too. I'm just curious, what causes this?

Answer by Kate
Hi yes its called the third eyelid or Haw and it is a second layer of protection for the eye thats all. It is completely normal.

there are some conditions where by the third eyelid does not retract properly and this needs to be treated by a vet but other than that it is simply another layer of protection for the eye.

i suppose cats need it as they are hunters and out in the wilds where by they could easy get something in their eye, a blade of grass for instance. nature provides an answer to everything.

best wishes kate

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