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Why is my cat hissing at a new kitten?

Bringing a new kitten into a home already occupied by a feline majesty requires a careful approach. While some cats hit it off with their new feline companion right off the bat, others might not be too thrilled with their future housemates. Your otherwise friendly and composed kitty may turn into a hissing, growling, and aggressive mess who doesn't know how to handle the new addition to the family.

Why is your cat hissing at a new kitten, and what can you do about it? Untamed explains how to create a tolerant environment if you're raising more than one feline.

Reasons your cat is hissing at the new kitten

Older cats may hiss at new kittens for many reasons, including:

  1. An abrupt change in the routine
  2. Jealousy
  3. Competitiveness
  4. Unwillingness to share the living space
  5. The kitten's over-the-top playfulness

Your cat doesn't like the change in the routine

Cats generally don't like changes and thrive when they have set schedules. For example, your kitty likes to know precisely when they will get their meals. If you feed them a combination of wet and dry meals, they prefer to know when they get what type of food. They also have a sleep, playtime, and grooming routine that helps them feel safe and relaxed.

A new kitten changes everything. Such a drastic disruption can make your feline friend misbehave and direct their aggression towards the perceived cause.

Adopting a new pet also changes your existing cat's environment. The new kitten gets their share of the space. There is a new cat bed, litter tray, toys, etc. Changes in cats' living environment are the most common reasons for:

  • Stress and anxiety
  • Irritation
  • Confusion

These feelings often manifest as hissing or violence towards the new kitten.

Your older cat will likely be a bit jealous

This is me protesting your decision to bring an intruder into my home.

Source: Pixabay

Your feline companion may not be used to sharing you with other animals. When you bring a new cat into your home, you suddenly have to divide your time and affection, and the older cat stops being the centre of attention.

Lack of attention can lead to frustration, hostility, and violent outbursts.

Your cat perceives the new kitten as their competitor

Sometimes, cats don't get on well because they are of the same gender. Two males are more likely to become aggressive to each other than two females, but there are no guarantees.

Your cats may also dislike each other because they have too much in common. Besides gender, they may also share colour, size, and other qualities.

The resident cat is usually the bully. If they decide that the new kitten is too similar to them, they may see them as a competitor and become hostile towards them.

The older cat may not be willing to share their territory

Cats are territorial creatures. They become attached to their living space and don't like sharing it with newcomers.

Hissing may be a manifestation of territorial aggression. When the new kitten arrives, your cat may feel like their territory has been invaded. This behaviour is expected in cats who are used to being the only pets in the household. Your kitty may try to chase away the intruder.

Your new kitten's enthusiasm may be too much for your cat

Your cat may not want to tolerate the kitten’s boundless energy.

Source: Pixabay

Kittens are highly energetic, which may be too much for your older cat who wants to relax and take it easy.

Before you pick a kitten, you should check whether their energy levels and temperaments are compatible. Active breeds like Bengals will do great with Siamese kittens who share their energetic personality. Similarly, British Shorthairs will get on with Ragdolls, who are equally laid back and easy-going.

How to get your cat to stop hissing at your new kitten

It's best to avoid having to solve the hissing problem by carefully introducing your new kitten to the older cat. If your older feline still shows signs of hostility, you can:

  • Give them plenty of attention—When you bring a new animal into your home, ensure the resident feline doesn't feel neglected. Don't cut the time you spend with them and show appreciation as much as you can
  • Ensure the new kitten has personal space—Both felines should have separate beds, litter trays, scratching posts, food and water bowls, and toys. It would help if you also designated different areas in your home for each cat, at least in the beginning
  • Don't interfere in their interaction unless necessary—Some hissing and growling are normal and will stop as the older cat gets used to the kitten. Step in and separate the cats only when the situation escalates
  • Let your older cat assert dominance—Cats like hierarchy, so allow your older kitty to establish their rank as the superior feline. Some hissing and swatting are fine because that's how the kitten learns about boundaries
  • Ensure your cats spend time together—The more they spend time together, the sooner they will get used to each other and form a bond. If the hissing starts turning to actual aggression, separate the cats until they calm down, and try again later
  • Reward cats for good behaviour— Tasty treats are a great way to reinforce good manners. When your older cat relaxes or behaves nicely toward the kitten, reward them. Bits of porkhambacon, beef, lamb, or chicken are fantastic snacks for training
  • Feed your kitties together—Your cats should associate the time they spend together with something positive. Make sure to give your kitties delicious and healthy food they will enjoy at the same time

Choose the right food to keep your felines happy and friendly

Tasty meals may be the foundation of a lifelong friendship.

Source: Mochamad Wildan

Food is essential for your cats’ health and general well-being. Your adult cat and your kitten will love wet food containing:

  1. Animal protein
  2. Animal fat

Why animal protein?

Cats are obligate carnivores, so they can't thrive on a vegetarian or vegan diet. Your older cat and new kitten need high-protein meals to stay healthy because meat and fish deliver all the essential amino acids (like taurine, lysine, and arginine), vitamins, minerals, and antioxidants. Animal protein is also the primary energy source for felines.

Grains, vegetables, fruits, and other carbs are not suitable for feline nutrition because they:

Check out the ingredients to look for in cat food and those to avoid:

Good ingredients

Bad ingredients

  • Turkey
  • Liver
  • Duck
  • Tuna
  • Sardines
  • Salmon
  • Mackerel
  • Shrimp
  • Prawns

Why animal fat?

Your kitties' food must be healthy but also delicious, especially when you use it to bribe them into liking each other. Animal fat in high-quality jellies and gravies tastes fantastic to cats.

More importantly, it provides fatty acids necessary for:

  • Efficient immune response
  • Good digestion
  • Healthy skin and fur
  • Cell integrity

Why wet food?

Dry food is convenient to store and serve and usually cheaper than canned meals. According to some vets, it is also good for dental health as it helps remove plaque build-up from teeth. The problem with kibble is that it's:

  • Highly processed—Dry food often contains meat derivatives, bone meals, taste enhancers, artificial colouring, and other harsh additives that underwent heavy heat processing to make the product tasty
  • Less hydrating—Cats on a kibble-diet need to drink lots of water. Felines are generally not avid drinkers, so if they don't get enough moisture from food, they often suffer from:
  • Full of carbs—Dry food usually has lower meat content and more vegetable protein and carbs. Cats who eat biscuits often suffer from obesity, a significant risk factor for:

How can Untamed help your cats get along?

Untamed—connecting felines.

Image (c) Untamed

Want to nudge your cat and new kitten to become friends quickly? Give them Untamed during their bonding sessions.

With our meals, you don't need to worry if your picky kitty will turn their nose up at the sight of food and direct their dissatisfaction at their new housemate. Every Untamed product is made with high-quality lean meat or fish with a hint of fat to make the food scrumptious.

Vets fine-tuned our homemade-inspired recipes, so they are suitable for all felines—whether a kitten, adultsenior, neutered tom, or pregnant queen. They are also free from all known allergens, so the chances of your kitty getting a food allergy are minimal. If your kitty is particularly sensitive, you can try our single-protein-source dishes—Tuck-In Tuna in Jelly and Chocka Chicken in Jelly.

Our recipes don’t include grainsvegetables, sugar, or additives, so they won’t cause tummy troubles, which often cause stress and aggressive behaviour.

Take our Try Now quiz, create customised meal plans for your kitties, and watch their relationship develop and thrive!

Getting an Untamed trial pack

Treat your feline friends to the Untamed starter pack. Here's what to do:

  1. Visit our Try Now page
  2. Select the products
  3. Place your order

Once you order our healthy and delicious cat food online, it will arrive at your doorstep in a day! If your kitties like the dishes, you can sign up for our cat food subscription.

You can easily modify, postpone, or skip an order and cancel your subscription from your account. Check out what our long-term clients whose feline friends switched to Untamed report:


The Untamed effect

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We abide by the highest ethical standards of cat food production:

  • Our packaging is fully recyclable
  • We cooperate with sustainable and cruelty-free suppliers
  • Our operations are carbon footprint neutral