Introducing rabbits to other pets or animals in your household should wait until the rabbit feels secure. Let him explore the room you are keeping him in and become comfortable with the environment before introducing your other pets. The rabbit will, of course, have some knowledge of the other pets' presence in the house because he will smell them and probably hear them. But if he does not yet see them, he will be more comfortable and settle in sooner.
The following suggestions are for introducing rabbits to cats and dogs. The same recommendations can be followed with ferrets, although if you own a ferret, you should be aware that some rabbits are never able to be in the presence of a ferret without becoming fearful. If your other pet is a guinea pig or hamster, it is the rabbit that should be watched for signs of aggression toward the smaller animal.
It is recommended to wait until your rabbit has been in his new home three days to a week before the initial meeting with a pet cat or dog. During this time, the rabbit should be kept in a room where the cat or dog is not allowed. When your rabbit appears quite comfortable in his new home, it is time for him to meet the family cat or dog. You should leave the rabbit in his cage in its usual spot and then allow the cat or dog (not the two at once if you have both) into the same room for a few minutes. Stay in the room the entire time and watch things closely. The cat or dog will likely go up to the cage and sniff at the rabbit, which will probably sniff back. Watch the rabbit closely. If he appears excessively frightened - he flattens himself, eyes bulging, or begins to thump - remove the other pet from the room immediately. If your other pet is a dog, try to keep it from barking, as this can often frighten a rabbit. After about 15 minutes, remove the other pet from the room. Repeat the process each day, lengthening the time about 15 minutes a day, for 5 days to a week or until the animals appear comfortable with each other's presence. Be sure you pay attention to both animals during these initial visits, letting both see that the other is a member of the family.
It is now time to have the rabbit meet the other pet out of his cage. Let the rabbit loose in the room first, leaving his cage door open so he can retreat if he feels he needs to. Then bring the cat or dog into the room (on a leash). While keeping the cat or dog under firm control, allow the rabbit to come forward and meet the other pet. He will most likely approach slowly, ears pointing forward, hindquarters up, tail pointing back. Should the rabbit's posture change to ears back and tail up like a flag, remove the cat or dog immediately, as the rabbit may be getting ready to lunge forward and bite. Fifteen minutes is long enough for the first visit. Repeat this for a day or two more, and if all is going well, you can allow the cat or dog in the room with the rabbit without being under restraint.
Unexpected problems can arise when a household contains rabbits and cats or dogs. Please remember, however, no matter how well a rabbit and cat or dog get along, never leave them both free and unattended. It only takes a moment, and your rabbit may be seriously injured or dead.