Cats can breed from about four months old, and British cat charities recommend neutering at around that age. Both operations are day procedures under general anaesthetic.
Neutering prevents unwanted litters, reduces roaming, fighting and spraying, and protects females from womb infection and mammary cancer.
Neutering is the surgical removal of a cat's reproductive organs: the testicles in a male, called castration, and the ovaries and usually the womb in a female, called spaying. It is the most common operation carried out on cats and is recommended for all pet cats that are not part of a planned breeding programme.
Cats can become pregnant from about four months of age, and British cat charities and veterinary bodies recommend neutering at around that age. A kitten is kept indoors until it has been done. Rescue centres normally neuter cats before rehoming them, or arrange it as a condition of adoption.
There is no benefit to a female in having a litter first, and brothers and sisters will mate with each other.
Neutering does not change a cat's character.
Both operations are done under general anaesthetic, and the cat normally goes home the same day. The practice gives instructions about withholding food beforehand, which are shorter for young kittens than for adults.
Castration is a brief procedure through small cuts that usually need no stitches. Spaying is done through a small incision in the flank or the middle of the belly, where a patch of fur is shaved. Having a microchip implanted while the cat is under the anaesthetic saves a separate appointment.
The cat is kept warm, quiet and indoors on the evening after surgery and offered a small meal. Males are usually back to normal within a day or two. Females are kept indoors and discouraged from jumping until the vet has checked the wound, commonly after about ten days.
Licking or chewing at the wound is prevented with a cone-shaped collar or a soft body suit supplied by the practice. Redness, swelling, discharge, a gaping wound, or a cat that is dull or not eating the next day are reasons to contact the vet.
A neutered cat needs fewer calories and tends to eat more. Reducing portions a little, or moving to a food made for neutered cats, and weighing the cat every few weeks prevents the gradual weight gain that often follows; see feeding a cat.
Several animal charities run schemes that reduce or cover the cost of neutering for owners on low incomes or certain benefits, and some run local campaigns open to everyone. Veterinary practices and the charities' own websites give the details.
Colonies of unowned cats are managed by trapping, neutering and returning them to their territory. The tip of the left ear is removed under the same anaesthetic so that a neutered cat can be recognised at a distance and is not trapped again.