Why shouldn't my pet have just one litter?

While it may seem harmless, letting your pet have one -- or even two -- litters can cause big problems. Even if you find homes for all (or most) of the puppies or kittens, what about their puppies and kittens? In less than a year, all those puppies and kittens will be grown dogs or cats and able to have litters of their own. On a daily basis, thousands of puppies and kittens, healthy but homeless are killed. Many of them came from "just one litter."