Before introducing your new cat to the dogs, set him up in a room by himself for a while. He needs to get his bearings in these new surroundings first. Once you're sure that he's comfortable and seems curious about checking out the rest of the family, then you can begin the introduction.
First take your dogs outside and play with them to fatigue them a bit and then offer them some food. A full tummy will inspire a much calmer reaction during the introduction. Place your dogs on a leash, have treats in your pocket and instruct your dogs to sit next to you. Have someone let the cat in the room. If your dogs lunge toward the cat or show any negative reaction, give them a mild correction. As soon as the dogs relax then reward them with a treat. This is how they learn that the cat isn't a toy to be chased.
Let the cat set the pace in terms of how close everyone should get. If the cat seems comfortable and chooses to go nose to nose with the dogs, that's fine as long as you watch the dogs' reactions carefully.
Keep your demeanor very casual and make this a positive experience for all the animals. Use treats and plenty of rewards.
The key to creating a happy multi-pet household is how you do the introduction. Cats and dogs speak different languages. Dogs are pack animals and can form instant friendships. Cats are territorial animals and need to form friendships in a much slower, safer fashion. It will be important for the dog to learn this. Don't worry, dogs are smart and they catch on very fast. It doesn't matter whether you get a pup or an adult as long as you're able to train him. If you do decide to get an adult though, make sure he/she doesn't have a negative history with cats from a previous home. If you adopt a large dog, it will be important to train him to respond to your voice commands since you don't want to get into a tugging match. If you are considering a large dog, it would be a worthwhile investment to work with a dog trainer or at least take him/her to obedience classes.
Make sure the cats' litter boxes are out of reach of the dog. This can be done by installing a baby gate across the doorway so the pup can't get into that room. The three main areas of concern are the litter box, food bowl, and napping areas. Make sure all three of these areas are dog-proof for your kitties. If you don't have a cat tree, it would be a good idea to get a multi-perched tree so your kitties have a safe place to get away from a playful pup if they'd rather be left alone.
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