An altered cat or dog is a better pet for your family. No family wants to cope with an unplanned litter. Spaying prevents your pet from giving birth to unwanted kittens or puppies. Males neutered early in life are less aggressive toward other males and are not distracted by females in heat. A neutered male will be less tempted to leave your property and cross that dangerous street searching for a mate.
Neutered males are also less likely to mark territory with their urine.
Spaying your female pet eliminates the problem of stray males camping in your yard and decreases her desire to roam and breed. You are helping to alleviate the cat and dog overpopulation problem. Many of these are the result of accidental breeding by free-roaming unaltered pets. The more pets spayed or neutered, the fewer cats and dogs will have to be destroyed. Common excuses for not spaying or neutering pets.