Expert: Ali - 2/25/2009

Question
what is the best way to introduce 2 male{both neutered both have claws}1 used to going outside/fighting11years old, 1 6yrs old inside cat babied. so far they are kept seperate, when by chance they get out together, the older cat runs after the younger which turns and hides. help. they have to learn to get along

Answer
Beverly,

The best way to proceed in your case depends on how long you've been trying to introduce these two cats. Questions about the general topic of new cat introductions are fairly common and I've answered countless inquiries on this subject. I will provide some general information in this answer, however if you'd like more detailed information you may want to check out my previous answers on new cat introductions. Another consideration in your case is which cat has lived in this household the longest, he would be the resident cat while the other cat would be considered the newcomer to the resident cat's territory and should be treated accordingly.

The nice thing about introducing animals to each other is that it can be done over if you make a mistake...Proper new cat introductions can sometimes determine whether your house will be peaceful or if there will be a constant power struggle between feline members of your family. I would recommend that you keep these two cats separated for a minimum of 2-3 weeks (with all of the usual kitty amenities, of course) and several visits from human members of the household each day. The isolation period serves two purposes, it allows your resident cat to become gradually accustomed to the new addition and vice versa as well as protecting your resident cat from any possible viral or bacterial infections this new kitty may have. I always recommend that a new additions to the household are checked over by a vet and tested for feline leukemia and FIV prior to being integrated into a household with each other. Feline leukemia and FIV are chronic viral infections similar to HIV/AIDS in people, they can be passed from cat to cat, don't worry though, they aren't transmissible to people.

The isolation period will cut down on or eliminate aggression from the new kitty and resident kitty as they will be able to smell and hear each other through a closed door. You can feed the resident cat and the new kitty on opposite sides of a closed door for the introduction period. Once the resident cat is trying to play with the new kitty under the door and are acting curious about his presence I would recommend letting them out and supervising the interactions between them very closely. It's probably a good idea to consider giving the resident cat and the new kitty a homeopathic remedy called Bach's Rescue Remedy which is a blend of flower essences designed to calm and reassure. Since the flower essences are preserved in a grape alcohol solution I would advise against trying to administer Rescue Remedy directly by mouth, instead you will want to add 5-7 drops of Rescue Remedy to a fresh bowl of water each morning. The cats will drink the water and get the Rescue Remedy that will help to ease them into this new situation which should help to prevent any excessive aggression. Rescue Remedy is used by some vets and pet parents worldwide as a safe non-pharmaceutical way to treat anxiety, fear, trauma and other similar emotions, it won't hurt pets or children. I would recommend that you try a dose of about 5-7 drops in each fresh bowl of water every morning, you may also want to add the same dose of Rescue Remedy to the new kitten's water so that everyone is peaceful and happy. You can generally find Rescue Remedy in health food stores, naturopathic pharmacies, in some mainstream pharmacies and I believe it can also be purchased online.

Cats are quite territorial and will tend to display aggression in varying degrees to any new cat coming into their territory. Isolating the new cat will allow your resident cat to become accustomed to the new arrivals in his own time. You can help this process along by feeding the cats on opposite sides of the closed door which will allow all of the kitties in question to associate something positive (food) with a change in their territory. It's very important to play with and give affection to the resident cat as well as the new guy, after all, isolation doesn't mean that their need to be loved changes. Another positive point to isolating the new cats is that you will gradually become familiar with the new cat and the isolation period allows you to find out what is normal for these cats in regards to energy levels, toilet habits, appetite, personality quirks and more.  Once the 2-3 week period of confinement is finished for the new kitty you can open the door and watch the interactions closely. If either of the cats respond with aggression I would suggest having a spray bottle handy to act as a deterrent. Never get in the middle of a cat fight as you can be seriously injured, use a broom to gently push the cats apart if necessary.