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Why is my neutered male cat growling at the female after kittens?

Updated on September 23rd, 2025

Pet's info: Cat | Mixed Breed | Male | 4 years and 11 months old | 15 lbs

My 5 yr old neutered cat is growling and hissing at our female cat since she had her kittens. He did this when she first wondered up, but eventually warmed up to her. Why is he doing this, could it have to do with male cats coming around since she's older now?

2 Answers

Most Helpful Answer

Dr. Melanie, BVSc MS

Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on March 30th, 2017

It could be that she smells differently now that she had kittens, and Homer views her as a stranger. There is a method you can use to help them get along again. I would separate the cats, and slowly reintroduce them to each other. Take Homer aggressive, and put him in his own room with his own food, water, and litter box. Keep the door closed, and for a few days, feed them both treats on other side of door so they associate each other's smell with a good experience. Then let the other cat in Homer's room while he is in a cat carrier. They can smell each other, but not be in contact. If either becomes upset or show signs of aggression, remove the second cat from the room, and try again later. Praise them when they interact appropriately. When they are interacting well with each other through the carrier, you can let Homer out of his room, and see how he interacts with the other cat. Praise them when they interact appropriately, and separate them with any sign of aggression or upset. I would get a cat tree with lots of shelves to give the cats vertical space to get away from each other. I would keep Homer in his room when you go out until they are comfortable with each other.
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Related Answers from Veterinarians

  • Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on January 5th, 2020

    When cats go to the vet, they can come back smelling differently and the other cats will view him as a stranger. I would slowly introduce them to each other. Take Winter, and put him in his own room with his own food, water, and litter box. Keep the door closed, and for a few days, feed them both treats on other side of door so they associate each other's smell with a good experience. Then let the other cats in Winter's room while he is in a cat carrier. They can smell each other, but not be in contact. If anyone becomes upset or show signs of aggression, remove the other cats from the room, and try again later. Praise them when they interact appropriately. When they are interacting well with each other through the carrier, you can let Winter out of his room, and see how he interacts with the other cats. Praise them when they interact appropriately, and separate them with any sign of aggression or upset. I would get a cat tree with lots of shelves to give the cats vertical space to get away from each other. I would keep Winter in his room when you go out until they are comfortable with each other.

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    4Pet Parents found this answer helpful

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