Purebred
Because pure-breeding creates a limited gene pool, purebred animal breeds are also susceptible to a wide range of congenital health problems.
[4] The opposite effect to that of the restricted gene pool caused by pure-breeding is known as hybrid vigor, which generally results in healthier animals.
The word "pedigree" appeared in the English language in 1410 as "pee de Grewe", "pedegrewe" or "pedegru", each of those words being borrowed to the Middle French "pié de grue", meaning "crane foot".
This comes from a visual analogy between the trace of the bird's foot and the three lines used in the English official registers to show the ramifications of a genealogical tree.
For example, until the 20th century, the Bedouin people of the Arabian Peninsula only recorded the ancestry of their Arabian horses via an oral tradition, supported by the swearing of religiously based oaths as to the asil or "pure" breeding of the animal.
Today the modern Anglo-Arabian horse, a cross of Thoroughbred and Arabian bloodlines, is considered such a case.
When dogs of a new breed are "visibly similar in most characteristics" and have reliable documented descent from a "known and designated foundation stock",[6] then they can then be considered members of a breed, and, if an individual dog is documented and registered, it can be called purebred.
[8] Out of the hundreds of millions of cats worldwide, almost none have any purebred ancestors, nor belong to a specific breed, because purebred cats are a human invention of the last 150 years and selectively bred from foundation stock by breeders in closed off lineages.
Written and oral histories of various animals or pedigrees of certain types of horse have been kept throughout history, though breed registry stud books trace back to about the 13th century, at least in Europe, when pedigrees were tracked in writing, and the practice of declaring a type of horse to be a breed or a purebred became more widespread.
Most domesticated farm animals among others can also have true-breeding breeds and breed registries, particularly cattle, water buffaloes, sheep, goats, donkeys, guinea pigs, chickens, fancy pigeons, domestic ducks, rabbits, and pigs.
Full blood cattle are fully pedigreed animals, where every ancestor is registered in the herdbook and shows the typical characteristics of the breed.
Embryo transfer techniques allow top quality female livestock to have a greater influence on the genetic advancement of a herd or flock in much the same way that artificial insemination has allowed greater use of superior sires.
