Damsire

Horse breeding is reproduction in horses, and particularly the human-directed process of selective breeding of animals, particularly purebred horses of a given breed. Planned matings can be used to produce specifically desired characteristics in domesticated horses. Furthermore, modern breeding management and technologies can increase the rate of conception, a healthy pregnancy, and successful foaling.

The male parent of a horse, a stallion, is commonly known as the sire and the female parent, the mare, is called the dam. Both are genetically important, as each parent provides half of the genetic makeup of the ensuing offspring, called a foal. Contrary to popular misuse, "colt" refers to a young male horse only; "filly" is a young female. Though many horse owners may simply breed a family mare to a local stallion in order to produce a companion animal, most professional breeders use selective breeding to produce individuals of a given phenotype, or breed. Alternatively, a breeder could, using individuals of differing phenotypes, create a new breed with specific characteristics.

A horse is "bred" where it is foaled (born). Thus a foal conceived in England but foaled in the United States is regarded as being bred in the US. In some cases, most notably in the Thoroughbred breeding industry, American- and Canadian-bred horses may also be described by the state or province in which they are foaled. Some breeds denote the country, or state, where conception took place as the origin of the foal.

Similarly, the "breeder", is the person who owned or leased the mare at the time of foaling. That individual may not have had anything to do with the mating of the mare. It is important to review each breed registry's rules to determine which applies to any specific foal.

In the horse breeding industry, the term "half-brother" or "half-sister" only describes horses which have the same dam, but different sires. Horses with the same sire but different dams are simply said to be "by the same sire", and no sibling relationship is implied. "Full" (or "own") siblings have both the same dam and the same sire. The terms paternal half-sibling, and maternal half-sibling are also often used. Three-quarter siblings are horses out of the same dam, and are by sires that are either half-brothers (i.e. same dam) or who are by the same sire.

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