Sudden Aggression towards other cats and humans

by Desiree
(Columbus MS)

My roommate and I have 4 cats together. Both of mine are relatively calm but playful cats. I have a male and a female and she has 2 females. My male cat is about 9mos old and was just recently neutered. Before that her oldest female cat would love on him when she would go in heat. Since about a week before he was fixed she has become aggressive toward not only him but the other 2 cats and us as well. She will let you love on her every now and then but mostly she just growls at everything and runs around the house trying to hide. She is particularly mean to my male cat by actually attacking him more often than just growling. What could be the cause of this problem??? I'm wondering if we got him fixed to late and she is pregnant and becoming protective?

Answer by KAte
Hi
Well this does sounds a little strange and I would say that her behaviour is not that of a pregnant cat, instead I would say that it sounds more like fear or maybe even ill health.

There are several reasons for cats to become aggressive please see my web page about this here
https://www.our-happy-cat.com/aggressive-cat-behavior.html

Either something has frightened her and she is reacting to this fear or she may be feeling unwell. You have two options if this behaviour continues. Either you will need to take her to the vets to rule out any illness or too try and give her back some confidence in herself , her surroundings and the other cats etc by giving her a period of confinement whilst reintroducing the cats to her in a controlled fashion (described here https://www.our-happy-cat.com/introducing-cats.html)

best wishes Kate

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