The main thing is that if you are to bring other species into your household, be sure that it is never an impulse purchase first of all, but also realize that so long as you supervise your animals, all should go well. At my house we have 5 dogs, 3 cats, 6 chickens, a turtle, and later today, 2 rats. Everything gets along fine, and half the time the chickens and my German Shepherd 7 month old pup will be napping out in the yard together. At other times he might be chasing them, or you see a hoard of chickens chasing a frightened pup. No matter how nice and calm they may act at times, you must always be aware that it is simply impossible to know what your pet might do next, so always pay close attention. I've never had a bad experiance though with the large mix of pets we have, they learn to live together.