Non recognition aggression problem between two siblings.

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Non recognition aggression problem between two siblings.

Post by Matt1981 » Sat Feb 25, 2017 1:35 am

Hi all

Just wanted some advice on this subject if anyone has encountered it before. About four months ago I adopted two kittens from the same litter male and female.

From day one they were the best of friends playing together/sharing food bowls even cuddling up and sleeping together. The male called Marmite is considerably bigger (2.6 kg) then the female Oreo (2.1kg) even though they are the same age 4 months old.

Marmite has always been the dominant one and has seemed to play a bit rough with her however they have always been close. Something dramatically changed yesterday

I was made aware that kittens can become sexually active from 4 months and wanting to avoid interbreeding I managed to get an early neuter from Marmite due to his weight. The vet I'm with don't normally neuter until 6 months.

So I took him in yesterday morning and whilst I was waiting spent the whole morning and afternoon playing with his sibling until it was time to collect him.

Op went fine I brought him home yesterday afternoon he was wearing a Elizabethan collar. After letting him out of the box it would appear the collar he was wearing startled Oreo and she spent the afternoon hiding from him. I did intend to lock him in a room reserved for the cats with a bed food water and a litter tray for a few hours to help him sleep off the anesthetic but he seemed restless and him and Oreo would meow at each other either side of the door. He seemed desperate to get out. The collar itself was causing him some discomfort and after an hour of watching him try and walk backwards to get it off and bumping into things. I decided I'd take it off him to make things more comfortable whilst monitoring him to ensure he didn't kick his wound.

He went to greet his sibling and was met with a hiss and an aggressive swat in the head. No claws involved but this process continued throughout the night. She would grown and hiss every time he went near her. He was clearly confused by this and ended up snuggling up with me overnight while she slept downstairs.

The next morning they seemed to be coexisting in the house whilst avoiding each other. Every time Marmite went near her she would still hiss or growl to warn him off but they would generally stay out of each other's way.

I've heard there's a behavioural issue called non-recognition aggression is this what's happening here? Simply the different smells from the vet and anesthetic etc are frightening his sister.

And did seeing him wearing the collar which seemed to scare her, cause a negative impression of those smells ? The good news is the wound seems to have healed fine I'm just desperate to heal the rift between the two. I've tried putting them in seoerate rooms but when I do she calls out to him through the door and vice-Versa so she seems to know it's him.

Another thought I had was she knows he's got a wound and is warning him he's vulnerable although this one seems far fetched. I had them both on my lap earlier stroking them with each hand. She did growl twice then but was quiet when I promoted her to shush.

They are not hurting reach other at the moment they are asleep on seperate cushions in the kitchen. But has just been a shock to see her so aggressive towards him.

Is this something that will pass on its own or is there anything else I can do?

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Re: Non recognition aggression problem between two siblings.

Post by booktigger » Sat Feb 25, 2017 8:51 am

You could try rubbing him with a towel to try and make him smell more familiar. I'm surprised he has been sent home with a collar though, I've never had a male come back with one

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Re: Non recognition aggression problem between two siblings.

Post by Crewella » Sun Feb 26, 2017 7:19 pm

It's a very common reaction to a cat coming home smelling of vets instead of their usual smell - cats rely on smell much more than sight. It should resolve itself as the smell goes and he starts to smell like himself again, but as Ruth says you can hurry it along a bit by rubbing him with something like a towel that smells of home - even try rubbing her first and then him with the towel.

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