Spay and neuter

Neutering, from the Latin neuter ("of neither sex"), is the removal of an animal's reproductive organ, either all of it or a considerably large part. "Neutering" is often used incorrectly to refer only to male animals, but the term actually applies to both sexes. The male-specific term is castration, while spaying is usually reserved for female animals. Colloquially, both terms are often referred to as fixing. In male horses, castrating is referred to as gelding. Modern veterinary practice tends to use the term de-sexing.

Neutering is the most common method for the sterilization of animals. In the United States, most humane societies, animal shelters, and rescue groups urge pet owners to have their pets neutered to prevent the births of unwanted litters, which contribute to the overpopulation of unwanted animals in the rescue system. Many states require that all adopted cats and dogs be sterilized before going to their new homes.

The practice has been advocated in radio and television commercials and on various shows, most notably the game show The Price is Right, whose host, Bob Barker, would end every episode with the catchphrase "Help control the pet population; have your pets spayed or neutered." After Barker's retirement, Drew Carey continued to sign off with his own message regarding spaying and neutering.

In female animals, spaying involves abdominal surgery to remove the ovaries and uterus (hystero-oophorectomy). Another option is to remove only the ovaries (oophorectomy), which is mainly done in cats and young dogs, and yet another, less commonly performed method is an "Ovary Sparing Spay" in which the uterus is removed but one (or both) ovaries are left. Traditional spaying (removal of uterus and ovaries) is performed commonly on household pets (such as cats and dogs), as a method of birth control. It is performed less commonly on , as a method of birth control or for other reasons. In mares, these other reasons include behavior modification.

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