MY Healthy cat hates my injured cat


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Oct 12, 2020
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I have two male cats who grew up together. They love each so much and also lick each other and play tag all the time. They are good friends. They even sleep together on the same pillow on each others bodies; All of a sudden, one of my cats got missing for 24 hours when we found him, he got bruised and injured with a limp and blood on many parts of the its body.

The other cat suddenly changed its attitude towards the injured cat, it hates the cat now and makes a gawking hiss sound anytime the cat comes close and also attacks the cat with teeth and claws when they are in the same proximity. When u try to bring the other cat near the injured cat its resists so hard and moves away with force. The healthy cats stays away from the injured, it doesnt sleep on the comfortable pillow were the injured cat sleeps.

Why does my healthy suddenly cat hate my injured CAT? Could it be the blood on the fur cuz i didnt bath the cat or what could it be?

how can i make them friends again



Top Cat
Feb 20, 2011
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Your injured cat picked up some unfamiliar odors when he was outdoors and if he was taken to the vet he is carrying vet smells as well. Your other cat is reacting with what is called Non Recognition Aggression. Usually the returning cat starts to smell more familiar after a few days and their relationship returns back to normal but you may speed things along by rubbing something of the aggressive cat on the injured one. If that doesn’t work, you can try a dab of pure vanilla on both.

I would also try a Feliway diffuser which can calm both cats and make the readjustment easier.


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May 27, 2013
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Mount Fuji, Japan
Hello cat+ion cat+ion

I'm sorry to hear one of your cats got hurt. Has the injured cat been checked over by a vet? It sounds like he was either attacked by another animal or hit by a car.

It's very important that he receives medical attention!

He could have broken bones or internal injuries. If another animal attacked him he will need to have the wounds cleaned properly and be given antibiotics to prevent infection. If he was attacked by another cat he could have a contagious disease, such as FIV or FeLV, that he could give to your healthy cat.

Please take him to the vet right away.

It's normal for your healthy cat to hiss at him. He smells strange, your cat can probably smell another animal on him and this is scaring him.

Keep the cats separate until your injured cat has been treated by a vet and recovered from his injuries. By that time he will smell as normal again and you can reintroduce the two of them.


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Adult Cat
Nov 13, 2018
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Most cats will react aggressively towards sick or injured cats - even if they are family or friends- a sick cat unfortunately needs to be separated ... ( and see the vet of course). Keep them both apart until your kitty feels well. Vet visits, outside fights... can change their smell and resident cats perceive that as a threat .... but ... cats also don't like weak or injured animals- in nature ... this makes sense as a weak animal is a danger to a group ... attracts predators ... Injured cats themselves tend to retract and want to be away from their usual group - find a nice and protected spot I your home and let your baby heal ... chances are that they will get along again once the medical issue is dealt with and healed .