At maturity (on average, 6 to 9 months of age), male dogs and cats are capable of breeding. Both male dogs and cats are likely to begin “marking” their territories by spraying strong-smelling urine on your furniture, curtains, and in other places in your house. Also, given the slightest chance, intact males may attempt to escape from home and roam in search of a mate. Dogs and cats seeking a female in heat can become aggressive and may injure themselves, other animals, or people by engaging in fights. Roaming animals are also more likely to be hit by cars.

Neutering male dogs and cats reduces the breeding instinct and can have a calming effect, making them less inclined to roam and more content to stay at home. Neutering your male pet can also lessen its risk of developing prostate disease and testicular cancer.