Hi all,

We have two cats that are brothers. They are best friends and have always been very loving to each other. One of them has had a few health issues over the past few years, including some eye issues. On Sunday, that brother suddenly violently attacked his other brother. It happened 3 times, and now we have to keep them separated. One is upstairs and one is in the finished basement. We went to the vet and she thinks the one brother is blind in one eye and may have had a sudden change in eyesight that caused the aggression. But in all other ways he's acting perfectly normal.

We're tried a few things to re-introduce them to one another, but the other cat starts growling in fear and it starts again. This is very upsetting because the two brothers have always been very close with no issues at all. They miss each other. My teenage son is even sleeping in the basement with the one brother so he doesn't cry all night. Any suggestions as to how to resolve this so they can get along again? It's very frustrating. We even tried having one in a cat carrier but the brother with the eyes issues started attacking again. I know they recommend a slow process of re-introduction. But I refuse to just let them fight it out in hopes of that resolving it. That's cruel, and could cause serious injuries.

Thanks for any help you can provide.

Chris

I can appreciate how upsetting this is from my own experience. There is a lot of information on the internet about this issue. It can happen when you take one of your cats to the vet and bring it home as well as like in your case, when one cat becomes sick or for no reason at all. In my case, it has happened several times over the years with our cats. Keeping them separated for a time and slowly introducing them into the same room under supervision over time has worked for me.

Did the cat's scent change for some reason?

Whenever we take our one cat to the vet, the other cat growls and attacks it when she gets home. Pretty sure it's because the one cat comes back with a different scent that the other cat doesn't recognize.

Thanks for the replies so far. No, there have been no events that should have caused their scent to change. They have always been inside cats. We only took the aggressive one to the vet after the attacks happened. Any previous visit to the vet was like a year ago.

The last time I took one of my cats to the vet for a checkup my other cat acted the same way. After a few weeks they were fine.

You may think that this sound goofy , but if they were my cats.... I'd give both of them a bath with the same shampoo.
After they've had time to get dry and get their wits about them.... the next day.... I would put the basement cat in a main floor bathroom. Bathroom doors tend to have a lot of clearance at the bottom. I would move their food dishes next to the bathroom door , so they can hear each other and smell each other and "play footsie"..... After a couple of day like this, I would then take the aggressive cat and put it in a kennel in the middle of the house and let the other cat wander freely around the house during the day and let the aggressive cat wander around the house at night time ( with the other cat locked safely in the bathroom).
I have no idea what would have set the cat off.... but worry that if you don't do something to change it's mind, that it will continue it's aggressive activities.

Let us know how this situation works out !!

Do they play with toys?

If they are playful, take a toy, play with one, then the other. Eventually, you can have them in the same room playing, the toy will distract them from the aggression.

Maybe catnip toys.

Brain tumor pressing on the optic nerve, now changing behavior. Very sorry.

quote:

Originally posted by Woodman:
Brain tumor pressing on the optic nerve, now changing behavior. Very sorry.

Wow, how do you know that ??

quote:

Originally posted by Woodman:
Brain tumor pressing on the optic nerve, now changing behavior. Very sorry.

Definitely more serious than just the loss of eyesight, as bad as that is. My girlfriend had several cats who lost their vision, and they simply made their way in life without any more issues.

Get a second opinion from another Vet, and do it ASAP! I'd look for a medical issue before worrying about a cat psychologist.

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Originally posted by mike28w:
Wow, how do you know that ??

Brain Cancer Symptoms & Signs | CTCA
https://www.cancercenter.com/brain-cancer/symptoms/
Some potential brain cancer symptoms include: Headaches: Having a headache could be related to many causes. A noticeable change in the frequency and intensity of headaches may indicate a brain tumor. Vision changes: A tumor on or near the optical nerve could cause blurred or double vision.

Irritability or aggression are right up there with the symptoms as well. The aggression and blindness together made me think first of a tumor.

A friend has a tumor on his brain stem which compromised his vision. None of the other symptoms. Stoic apathy, maybe?

Its the scent thing. While people are amazed by the sense of smell a dog has, cats rely on scent too. You vet may have handled several cats prior to your visit and his office is full of cat smells too.
Re-introduce them slowly and see what happens.

Assuming there's not a medical issue directly causing the aggression...

Regarding scent, you can try giving them each something to use as bedding, such as an old tshirt, and try swapping them between the two cats daily.

Something I'd also try would be to get the aggressor used to being in a crate. Make it cozy. Maybe a wire crate so he can see out, but you can use towels to cover some of it to make it more snug and appealing.

If he takes to it, then he can be closed up in the crate while you let the other one play with a toy nearby, multiple times a day. Use a lure-type toy on a string, so you can control how close the toy gets to the crate. Play at whatever distance allows the cat in the crate to remain relaxed, then gradually move the play closer and closer to the crate. Take your time, over days if that's what it takes. I'd be careful to not let the other cat near the crate until you felt the cat in the crate has shown increased tolerance of the other getting closer and closer.

Also, maybe you can feed them next to each other, but with the one in the crate.

The point is to gradually desensitize the aggressor to the presence of the other cat; to let him know he's in no danger when the other cat is nearby.

Also, watch several episodes of My Cat from Hell. Lots of good insight, IMO.

Thanks for all the suggestions. I appreciate it.

Again, we only took the aggressive one to the vet after the attacks happened. Any previous visit to the vet was like a year ago. So I doubt it's a scent thing.

The cats have been on the other side of the basement door for a few days. They know each other is there. And we've been feeding them close to the door to get comfortable.

They do have some toys they play with and we can try that. They actually both love this cat string game video on YouTube, which we plan to play for them as they get closer together. We also plan to put them both in their carriers so they can see each other. First at a distance and gradually get closer as long as they behave. It would be nice if we could somehow put up a screen of some kind to see each other but still be loose, but that's not really possible.

I suppose it could be a brain tumor, but who knows at this point.

quote:

Originally posted by Woodman:

quote:

Originally posted by mike28w:
Wow, how do you know that ??

Brain Cancer Symptoms & Signs | CTCA
https://www.cancercenter.com/brain-cancer/symptoms/
Some potential brain cancer symptoms include: Headaches: Having a headache could be related to many causes. A noticeable change in the frequency and intensity of headaches may indicate a brain tumor. Vision changes: A tumor on or near the optical nerve could cause blurred or double vision.

Irritability or aggression are right up there with the symptoms as well. The aggression and blindness together made me think first of a tumor.

Not saying this is what’s happening with the OP’s cat, but this is exactly what happened with one of our 2 cats. The female one day went bat shit crazy and tried to kill the male cat, they had been buddies for 14 years. The vet blamed it on BS things like possible strays outside. We don’t have any and it was clearly a drastic personality change.

About a month later one of her eyes showed problems and it was stated by a different vet that she had a tumor behind it. We had to keep them separated for 4 months before we could gradually reintroduce them. She eventually got sick enough that we had to put her to sleep. The vet said there was nothing we could do, but not sure if there would have been options if the real root cause had been discovered sooner.

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Originally posted by Brett B:
The vet said there was nothing we could do, but not sure if there would have been options if the real root cause had been discovered sooner.

Chris, I'd address this NOW, with another Vet. If it's something serious, your cat could be in for months of suffering.

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I'd give both of them a bath with the same shampoo.

Good luck with that!

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Originally posted by Chris17404:
Any previous visit to the vet was like a year ago. So I doubt it's a scent thing.

That being said, it still might be helpful to do the bedding swap thing I mentioned previously, since the cat with the vision issue may need to rely more on scent now to identify his brother. It could be that he's just not visually recognizing him, and he's already stressed due his decreased vision. Also, stress hormones can linger in an animal's system for days, so the trip to the vet combined with the loss of vision may have had him on edge.

quote:

Originally posted by 229DAK:

quote:

I'd give both of them a bath with the same shampoo.

Good luck with that!

It's not that bad ....just noisy...

Is aggressive kitty also being moody with people, or just his kitteh friend? Thyroid issues can cause behavior modification, though you often see weight loss, increased activity (normal adult cats sleep a TON), and normal to increased appetite with it. Just a thought, might let the vet check the T4 level, cost for test itself is usually $25-45 dollars.

If the vet didn't do general labs, talk to them about doing a general wellness test (send out option, if they offer that, is usually cheaper), and ask that they do the one with the thyroid screen in there. Good peace of mind.

The bath suggestion for both of them is actually a pretty solid idea; sometimes cats smell things we can't, and if victim kitteh expressed his anal sacs or something similar and it's freaking aggressive kitteh out, it might mitigate the situation. Along that same thought curve, sometimes if the victim cat is sick and emitting a confusing odor, the other cat will change it's behavior. Maybe BOTH cats need a good checkup?

Lastly, they sell Feliway plug in's and wipes that use calming pheromone type actions, and they can really help settle flustered cats down. Good luck!