Glossary

Neuter

Surgery that removes a male dog's testicles, preventing breeding and some health problems and sometimes changing certain behaviors.

Also called: neutering, castration, spay and neuter, sterilizing a male dog, orchiectomy

Neutering, or castration, is a surgery in which a vet removes the testicles of a male dog under general anesthesia. It ends the ability to father puppies, prevents testicular cancer and lowers the chance of some prostate problems. It may also reduce roaming and urine marking, though it does not fix training problems or general aggression.

For many large breeds, studies suggest that very early neutering can raise the risk of some joint disorders and cancers, so timing is now individual. Practices differ by breed, size, lifestyle and country, and shelters and rescues may sterilize much earlier for population reasons.

Most dogs recover in about ten to fourteen days. The cost is usually lower than for a spay. The term is also used loosely for both sexes, in which spay and neuter together mean sterilizing a dog. Ask a veterinarian about the best timing for your puppy.

Last reviewed November 8, 2026

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Related terms

Spay Surgery that removes a female dog's ovaries, and usually the uterus, to prevent pregnancy and heat cycles and eliminate the risk of pyometra. Anesthesia A medically induced, controlled loss of consciousness for surgery, dental cleaning or imaging, with monitoring throughout. Wellness exam A routine, nose-to-tail check-up of a healthy dog that updates vaccines, screens for hidden problems and tracks weight over time.