You can tell a lot from a cat’s eyes both in respect of health, mood and more.
All of the below require the intervention of a vet.
You must have heard of it, the nictitating membrane. This is the third eyelid a.k.a the haw. Its role is to protect a cat’s eyes when they’re closed. If you can see this membrane when the eyes are open your cat may be unwell. You will see it extending from the inner corner of the eye across the eye to various extents. It is off-white.
If your cat has one pupil bigger than the other this may also indicate a health problem.
If the whites of your cat’s eyes are yellowish, even a faint yellow it may be indicative of jaundice or liver problems. In order to see the whites of a cat’s eyes you may need to gently raise her eyelids to check.
If there are greenish-yellow secretions coming out of your cat’s eyes and conglomerating in the corner of the eye it may be a sign of a bacterial infection. There may be pink, inflammed membrane around the eye as well, confirming a bacterial infection.
If your cat’s eyes are constantly tearing and the tears are running down the side of the face, from the corner down the side of the nose, the cause may be a damaged cornea. An exception to this diagnosis is that in flat-faced cats such as the Persian, tearing is the default health condition because the tear duct is distorted through breeding which prevents it from draining tears effectively so they overflow the tear duct and run down the face.
If your cat is blinking more than normal or the eyelids are droopy it may be a sign of health problems because a cat’s corneas are not that sensitive and therefore they don’t need to blink as often as people.
Changes to a cat’s eyes can signal a mood change. They become greatly enlarged when they see something very appealing or threatening. Wide-open eyes are a sign of strong emotional arousal. This causes an exaggerated expansion of the pupil. The pupil might increase in size between four and five times.
The amount the eyelids open or close can also signal mood. When a cat is alert the eyes are fully open and the eyelids fully withdrawn. You’ll see this when your cat meets a stranger who can’t be trusted. When the eyelids are half closed across the eye it signals a relaxed cat who can trust the person opposite. This occurs with the classic slow blink. When a cat is relaxed in the presence of their owner, perhaps on their lap and communicating with their owner, they may do a slow blink which cat lovers tell us is a sign of love. It is partly, but it is more accurately a sign of contentment and relaxation in the cat.
Sometimes a cat’s eyelids may be fully closed and this happens under two circumstances: sleep and appeasement according to Dr Desmond Morris. In regards to appeasement, if one cat is forced into submission in a fight they may perform what he describes as “cut-off”. The cat will turn away and close his eyes. He describes this as the cat trying to blot out the “frightening image of its dominant rival”.
It is essentially a protective action to save the eyes from being damaged. It also reduces the tension of the moment. To the victor it is a sign of capitulation.
The direct stare is the opposite. It is a hostile signal and a well-known aspect of feline body language.
You can tell when a cat is a true albino: their eyes are pink. See the picture below.
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