Foundation stock

Foundation stockorfoundation bloodstockrefers to animals that are the progenitors, or foundation, of abreedor of a given bloodline within such. Many modern breeds can be traced to specific, named foundation animals, but a group of animals may be referred to collectively as foundation bloodstock when one distinct population (including bothlandracebreeds or a group of animals linked to a deliberate and specificselective breedingprogram) provides part of the underlying genetic base for a new distinct population.

Terminology

The terms for foundation ancestors differ by sex, most commonly "foundation sire" for the father and "foundation dam" for the mother. Depending upon thespeciesin question, more specialized terms may be used, such asfoundation marefor female horses,foundation queenfor female cats, orfoundation bitchfor female dogs.

The offspring of genetically dissimilar parents or stock, whether of different species or different breeds are technically calledhybrids.InMendelian genetics,the foundation generation is the first set of unrelated parents ( "P" ) to be mated to one another. A first generationhybriddescendant from these parents is called aF1 hybrid(F₁) or filial 1 hybrid, with subsequent generations designated F₂and so on.

Related concepts include:

• Founder effect— the loss ofgenetic variationthat occurs when a newpopulationis established by a very small number of individuals from a larger population.It is a special case ofgenetic drift,where subsequent generations may have less genetic variation than the original population, which leads tofixation.On one hand, fixed traits are what creates a standardized breed of animal, but if the level ofinbreedingbecomes significant, it can make the new population more vulnerable to extinction.Founder effect can also lead to the development of new species.
• Designer crossbred—Usually describes F1 crosses between two different animal breeds.
• Population bottleneck—whenGenetic driftoccurs more rapidly on account of a dramatically diminished population size.

Dogs

In dog breeding, the process of becoming a standardized, officially recognized breed in the United States requires keeping meticulous records for several generations. To facilitate this process, TheAmerican Kennel Cluboperates abreed registryfor over 60 nascent and experimental breeds, called theFoundation Stock Service Program(FSS), through which breeders can seek to establish full AKC recognition of their new breeds.

Horses

Inhorse breeding,there are usually a much smaller number foundation sires than foundation dams. In some cases, named foundation mares are not always identified in oldpedigree recordsat all. Conversely, in other cases, such as inThoroughbred breeding,pedigree families are traced to the tail-female line. Breeds that require that all members trace to specific foundation stock have aclosed stud bookand prohibit or strongly limitcrossbreedingto other animals. TheThoroughbred,AndalusianandArabianare examples of breeds with a closed stud book.

Some breeds with an establishedphenotypeand named foundation stock may still permit outside bloodlines, usually from the foundation breeds from which they came, to contribute further to the genetic base of the breed; these thus have at least partiallyopen stud books.An example of a partially open stud book is that of theAmerican Quarter Horse,which still allows limited registration of animals with one Quarter Horse parent and one Thoroughbred parent. Newer breeds, such as many of thewarmbloodbreeds, may have mostly open stud books, where horses that are registered may be of a variety of bloodlines, but must first pass a rigorousstudbook selectionprocess.

Some breeds, such as theMorgan horse,have a single named foundation sire, while others, such as theLipizzan,or theAmerican Quarter Horse,may have several. In some cases, particularly with older horse breeds, some or all foundation sires may be unknown. However, in breeds with a well-documentedbreed registry,all or nearly all foundation animals may be identified. For example, there are three major foundation sires of the Thoroughbred, and another 24 or 25 minor foundation sires, along with 74 foundation mares. An example of a foundation bloodstock pedigree line within a breed are the Crabbet lines from theCrabbet Arabian Studfarm in England. These animals were bred by the same program for 92 years, were exported worldwide, and had a substantial impact on the breed. Some Arabian breeders today specialize in horses descended only from this breeding program. Similarly, in theStandardbred,theClay Trotting Horsesconstitute a distinct foundation line within that breed.

An example of a breed formed by foundation stock from other breeds, but not necessarily all from named individual animals, is theHackney horse,with bloodlines contributed from Thoroughbred andNorfolk Trotter.In other cases, where a breed orlandraceis older than any written records, the foundation bloodstock is sometimes described by myths or legends, such as the mythical horses ofMohammad,known asAl Khamsa( "The Five" ), claimed in legend as the foundation mares of theArabian horsebreed.

The word "foundation" is also sometimes applied to horses of aphenotypethat resembles that of the original foundation stock, particularly when the modern look of the breed has diverged from the original stock. The word may refer to animals tracing only to a select subset of the oldest foundation bloodlines, particularly when newer breeding has been added that changed the original phenotype.