$86 allows Paws Chicago to spay or neuter one animal. Spaying or neutering animals helps curb overpopulation and increases the life expectancy of a pet. Pet overpopulation is a serious problem and nearly 2.7 million healthy dogs are euthanized each year. In many communities, the law requires pets to be spayed and neutered in an effort to reduce stray populations. Spaying or neutering an animal can help to reduce overpopulation, reduce animal aggression and increase the life expectancy of the animal. Altered dogs typically live 1-3 years longer, while cats live 3-5 years longer.