Spaying and neutering are the respective processes of
female and male animal
sterilization, in order to keep them from producing offspring.
Unlike in humans, this usually includes (somewhat
controversially) the entire removal of related major organs. While most
agree on the advantages of sterilization itself, the necessity of the castration
part is even now hotly debated.
The processes are sometimes referred to as
castration, due to the removal of organs, although the term in itself
specifically refers to the removal of the male testicles.
animal shelters, and
rescue groups urge pet owners to have their pets "spayed or neutered" to prevent
the births of unwanted and accidental litters, contributing to the
overpopulation of animals.
In addition, the process has theoretical health benefits (uterine and
testicular cancer or similar diseases are definitely ruled out, and
hormone-driven diseases such as breast become a non-issue as well), and it may help to address behavioral
issues that otherwise can result in animals being given up to shelters,
euthanised. Obviously, the animals lose their
libido, and females no longer experience heat cycles. This is due to the great hormonal changes involved with both
genders, and any neutering will definitely cause minor personality changes in
Modern Non-surgical Alternatives
Male dogs - "Neutersol" (Zinc gluconate neutralized by arginine).
Cytotoxic; produces infertility by chemical disruption of the testicle.
Female mammals - "SpayVac" (purified porcine zona pellucida antigens
encapsulated in liposomes - cholesterol and lecithin - with an adjuvant.)
Produces infertility by inducing an immune response to the egg.
In female animals, spaying involves invasive abdominal surgery to remove the
ovaries and uterus, rarely
involving major complications. It is commonly practiced on household pets such
as cats and
dogs as a method of birth control, but is rarely performed on livestock.
Possible complications include urinary incontinence and minor weight gain.
Terms for the spayed
A specialized vocabulary in
animal husbandry and -fancy
has arisen for spayed females of given animal species:
In male animals, neutering involves the removal of the testes, and is
commonly practiced on both household pets (for birth control) and on livestock
(for birth control, as well as to improve commercial value). It is often
recommended in cases of undesirable behavior ("roaming, marking, aggression, and
mounting") in domestic animals, but studies suggest that "the behavioral
modification effects of surgical castration ... are far from absolute".
Additionally, the utility of castration to prevent testicular and prostatic
cancer appears to be limited: surgically castrated dogs display a markedly
increased incidence of prostatic cancer, and the incidence of malignant
testicular cancer in animals is very low.
Terms for the neutered
Neutered males of given animal species also have specific names: