Neutering (Males) Neutering, or orchiectomy, is a surgical procedure where the testicles are removed from males, preventing them from fathering litters of kittens or puppies. Cats - Neutering your cat can help to curb undesirable behaviours such as spraying, roaming and aggression towards other cats. Dogs - Neutering your dog may help to reduce animal aggression, 'humping', and attempts at escaping your home or yard. Spaying (Females) Spaying, technically known as an ovariohysterectomy, removes a female's reproductive organs. This surgery prevents your cat or dog from becoming pregnant. Cats - Spaying your cat may help prevent them escaping your home, roaming, yowling and urinating inappropriately. Dogs - Having your female dog spayed ends their heat cycle and helps prevent mammary tumours, ovariectomy, and pyometra, which is a serious and sometimes fatal infection of the uterus.