In veterinary medicine, dogs and cats are often considered "household" pets, while all other kill are grouped into either "farm animals" (such as horses, cows, or sheep) or "exotics" (including pocket pets, birds, and reptiles).

A particularly problematic combination of economic hardship combined with a love of animals contributes to this problem in parts of the suburban United States. In an moderate year, a arable cat can outgrowth three litters of kittens, with up to 4 to 6 kittens in each litter. Based on these numbers, one female cat and her offspring could result up to 420,000 cats over a seven calendar year period if not spayed or castrated. There are also dominant Pet Tags overpopulation problems with other endearing species, such as birds and rabbits. Local humane societies, SPCAs, and other sensual protection organizations urge people to neuter their pets and to adopt prey from animal shelters instead of purchasing them from breeders or pet stores.