Neutering in the context of "Overpopulation of domestic pets"

Castration is any action, surgical, chemical, or otherwise, by which a male loses use of the testicles: the male gonad. Surgical castration is bilateral orchiectomy (excision of both testicles), while chemical castration uses pharmaceutical drugs to deactivate the testes. Some forms of castration cause sterilization (permanently preventing the castrated person or animal from reproducing); it also greatly reduces the production of hormones, such as testosterone and estrogen. Surgical castration in animals is often called neutering.

Castration of animals is intended to favor a desired development of the animal or of its habits, as an anaphrodisiac or to prevent overpopulation. The parallel of castration for female animals is spaying. Castration may also refer medically to oophorectomy in female humans and animals.

Population control is the practice of artificially maintaining the size of any population. It simply refers to the act of limiting the size of an animal population so that it remains manageable, as opposed to the act of protecting a species from excessive rates of extinction, which is referred to as conservation biology.

While many abiotic and biotic factors influence population control, humans are notably influential against animal populations. Whether humans need to hunt animals for food, exterminate a pest, or reduce competition for resources, managing populations involves providing nourishment, or neutering to prevent reproduction, culling individuals or the use of pesticides. Population control plays an important role in wildlife populations. Based on the species being dealt with, there are numerous ways populations of the wild are controlled. Wildlife contraception is the act of preventing reproduction in the wild, which subsequently decreases populations. An example of this includes the maintenance of deer populations with the use of vaccines. Other methods to maintain populations include lethal trapping, live trapping, egg/roost site manipulation, live-ammunition shooting, and chemical euthanization. Lethal trapping, egg/roost site manipulation, live-ammunition shooting, and chemical euthanization are methods used to eliminate animal populations and prevent reproduction, whereas live trapping captures species to remove them from a specific area.

The cat (Felis catus), also referred to as the domestic cat, is a small carnivorous mammal. It is an obligate carnivore, requiring a predominantly meat-based diet. Its retractable claws are adapted to killing small prey species such as mice and rats. It has a strong, flexible body, quick reflexes, and sharp teeth, and its night vision and sense of smell are well developed. It is a social species, but a solitary hunter and a crepuscular predator.Cat communication includes meowing, purring, trilling, hissing, growling, grunting, and body language. It can hear sounds too faint or too high in frequency for human ears, such as those made by small mammals. It secretes and perceives pheromones. Cat intelligence is evident in its ability to adapt, learn through observation, and solve problems. Female domestic cats can have kittens from spring to late autumn in temperate zones and throughout the year in equatorial regions, with litter sizes often ranging from two to five kittens.

The domestic cat is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the domestication of the cat started in the Near East around 7500 BCE. Today, the domestic cat occurs across the globe and is valued by humans for companionship and its ability to kill vermin. It is commonly kept as a pet, working cat, and pedigreed cat shown at cat fancy events. Out of the estimated 600 million domestic cats worldwide, 400 million reside in Asia, including 58 million in China. The United States leads in cat ownership with 73.8 million cats, followed by the United Kingdom with approximately 10.9 million cats. It also ranges freely as a feral cat, avoiding human contact. Pet abandonment contributes to increasing of the global feral cat population, which has driven the decline of bird, mammal, and reptile species. Population control includes spaying and neutering.

A foal is an equine up to one year old; this term is used mainly for horses, but can be used for donkeys. More specific terms are colt for a male foal and filly for a female foal, and are used until the horse is three or four. When the foal is nursing from its dam (mother), it may also be called a "suckling". After it has been weaned from its dam, it may be called a "weanling". When a mare is pregnant, she is said to be "in foal". When the mare gives birth, she is "foaling", and the impending birth is usually stated as "to foal". A newborn horse is "foaled".

After a horse is one year old, it is no longer a foal, and is a "yearling". There are no special age-related terms for young horses older than yearlings. When young horses reach breeding maturity, the terms change: a filly over three (four in horse racing) is called a mare, and a colt over three is called a stallion. A castrated male horse is called a gelding regardless of age; however, colloquially, the term "gelding colt" is sometimes used until a young gelding is three or four. (There is no specific term for a spayed mare other than a "spayed mare".)

Cats (Felis catus), initially introduced into Australia with the First Fleet in 1788, now number more than 11 million distributed across more than 90% of the continent including every major island.

They are the second most popular pet by household (third most populous overall after dogs and fish). In 2023 there were 5.3 million kept as pets of which approximately 95% are neutered. In addition there are estimated to be up to 6 million feral cats found in almost every remote area across the country.