A crossbreed is an organism with

purebred Purebreds are "cultivated varieties" of an animal species achieved through the process of selective breeding. When the lineage of a purebred animal is recorded, that animal is said to be "pedigreed". Purebreds breed true-to-type which means the p ...

parents of two different breeds, varieties, or populations. ''Crossbreeding'', sometimes called "designer crossbreeding", is the process of breeding such an organism, While crossbreeding is used to maintain health and viability of organisms, irresponsible crossbreeding can also produce organisms of inferior quality or dilute a

gene pool to the point of

extinction Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

of a given

breed A breed is a specific group of domestic animals having homogeneous appearance (phenotype), homogeneous behavior, and/or other characteristics that distinguish it from other organisms of the same species. In literature, there exist several slig ...

of organism. A domestic animal of unknown ancestry, where the breed status of only one parent or grandparent is known, may also be called a crossbreed though the term "mixed breed" is technically more accurate.

Outcrossing Out-crossing or out-breeding is the technique of crossing between different breeds. This is the practice of introducing distantly related genetic material into a breeding line, thereby increasing genetic diversity. Outcrossing can be a useful ...

is a type of crossbreeding used within a purebred breed to increase the genetic diversity within the breed, particularly when there is a need to avoid

inbreeding Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. By analogy, the term is used in human reproduction, but more commonly refers to the genetic disorders and o ...

. In animal breeding, ''crossbreeds'' are crosses within a single species, while '' hybrids'' are crosses between different species. In plant breeding terminology, the term ''crossbreed'' is uncommon, and no universal term is used to distinguish hybridization or crossing within a population from those between populations, or even those between species.

Designer crossbreed

A designer crossbreed or designer breed is a crossbred animal that has

parents, usually registered with a

breed registry A breed registry, also known as a herdbook, studbook or register, in animal husbandry and the hobby of animal fancy, is an official list of animals within a specific breed whose parents are known. Animals are usually registered by their breede ...

, but from two different

s. These animals are the result of a deliberate decision to create a specific crossbred animal. Less often, the animal may have more than two pure breeds in its ancestry, but unlike a mutt or a

mongrel A mongrel, mutt or mixed-breed dog is a dog that does not belong to one officially recognized Dog breed, breed and including those that are the result of intentional Dog breeding, breeding. Although the term ''mixed-breed dog'' is sometime ...

, its entire pedigree is known to descend from specific known animals. While the term is best known when applied to certain

dog crossbreed Dog crossbreeds, sometimes called designer dogs, are dogs which have been intentionally bred from two or more recognized dog breeds. They are not dogs with no purebred ancestors, but are not otherwise recognised as breeds in their own right, ...

s, other animals such as cattle, horses, birds and cats may also be bred in this fashion. Some crossbred breeders start a freestanding breed registry to record designer crossbreds, other crossbreds may be included in an "appendix" to an existing purebred registry. either form of registration may be the first step in recording and tracking pedigrees in order to develop a new breed. The purpose of creating designer crossbreds is usually one or more of the following reasons: # to breed animals with

heterosis Heterosis, hybrid vigor, or outbreeding enhancement is the improved or increased function of any biological quality in a hybrid offspring. An offspring is heterotic if its traits are enhanced as a result of mixing the genetic contributions of ...

, commonly known as "hybrid vigor", # to create animals with more predictable characteristics than

mixed breed A mixed breed is a domesticated animal descended from multiple breeds of the same species, often breeding without any human intervention, recordkeeping, or selective breeding. Examples include: * Mixed-breed dog, a dog whose ancestry is compl ...

breeding, # to avoid certain undesirable

recessive In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and t ...

traits that lead to

genetic disease A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders ...

s that plague many purebred animals, # to develop an animal that combines what are viewed as the best traits of two or more breeds, # as the preliminary steps toward developing a new animal breed. Breeders of designer crossbreds borrow the

technical language Jargon is the specialized terminology associated with a particular field or area of activity. Jargon is normally employed in a particular communicative context and may not be well understood outside that context. The context is usually a particu ...

from

hybrid Hybrid may refer to: Science * Hybrid (biology), an offspring resulting from cross-breeding ** Hybrid grape, grape varieties produced by cross-breeding two ''Vitis'' species ** Hybridity, the property of a hybrid plant which is a union of two dif ...

plant breeding: A first generation, 50–50 crossbred is an F1 cross. Subsequent generations may see a purebred animal crossed back on a crossbred, creating a 75/25 cross, or a BC1 or F1b "

backcross Backcrossing is a crossing of a hybrid with one of its parents or an individual genetically similar to its parent, to achieve offspring with a genetic identity closer to that of the parent. It is used in horticulture, animal breeding, and product ...

." The breeding of two crossbreeds of the same combination of breeds, creating a F2 cross, an animal that is still a 50–50 cross, but it is the second

filial generation An F1 hybrid (also known as filial 1 hybrid) is the first filial generation of offspring of distinctly different parental types. F1 hybrids are used in genetics, and in selective breeding, where the term F1 crossbreed may be used. The term is somet ...

of the combination. A F2 cross bred to an F2 cross creates a F3 cross. Similarly, a F2 animal bred to an F1 animal creates a F2b backcross. F3 crosses and greater are called "multi-generational" crosses. In dog breeding, three generations of reliable documented breeding can be considered a "breed" rather than a crossbreed. There are disadvantages to creating designer crossbreeds, notably the potential that the cross will be of inferior quality or that it will not produce as consistent a result as would breeding purebred animals. For example, the

Poodle , nickname = , stock = , country = Germany or France (see history) , height = , maleheight = , femaleheight = , weight = , maleweight = , femaleweight = , coat ...

is a frequent breed used in creation of designer crossbreeds, due to its non-shedding coat, but that trait does not always breed true when it is part of a designer cross. Also, because breeders of crossbred animals may be less careful about genetic testing and weeding out undesirable traits, certain deleterious

dominant gene In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and t ...

s may still be passed on to a crossbreed offspring. In an F2 cross, recessive genetic traits may also return if the parent animals were both carriers of an undesired trait.

Crossbreeds in specific animals

Cats

The many newly developed and recognized breeds of domestic cat are crossbreeds between existing, well-established breeds (sometimes with limited hybridization with some wild species), to either combine selected traits from the

foundation stock Foundation bloodstock or foundation stock refers to animals that are the progenitors, or foundation, of a breed or of a given bloodline within such. Many modern breeds can be traced to specific, named foundation animals, but a group of animals ma ...

, or propagate a rare

mutation In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mi ...

without excessive

. However, some nascent breeds such as the

Aegean cat Aegean cats ( el, γάτα του Αιγαίου ''gáta tou Aigaíou'') are a naturally occurring landrace of domestic cat originating from the Cycladic Islands of Greece and western Turkey. It is considered a natural cat, developing without ...

are developed entirely from a local

landrace A landrace is a domesticated, locally adapted, often traditional variety of a species of animal or plant that has developed over time, through adaptation to its natural and cultural environment of agriculture and pastoralism, and due to isolation ...

population. Most

experimental cat breeds The following is a list of experimental cat breeds and crossbreeds that do not have the recognition of any major national or international cat registries, such as The International Cat Association (TICA) in the US, Europe, and Australasia; the Go ...

are crossbreeds.

Cattle

In cattle, there are systems of crossbreeding. In many crossbreeds, one animal is larger than the other. One is used when the purebred females are particularly adapted to a specific environment, and are crossed with purebred bulls from another environment to produce a generation having traits of both parents.

Sheep

The large number of breeds of sheep, which vary greatly, creates an opportunity for crossbreeding to be used to tailor production of lambs to the goal of the individual stockman.

Llamas

Results of crossbreeding classic and woolly breeds of llama are unpredictable. The resulting offspring displays physical characteristics of either parent, or a mix of characteristics from both, periodically producing a fleeced llama. The results are increasingly unpredictable when both parents are crossbreeds, with possibility of the offspring displaying characteristics of a grandparent, not obvious in either parent.

Dogs

A ''crossbred'' dog is a cross between two (sometimes more) known breeds, and is usually distinguished from a '' mixed-breed dog'', which has ancestry from many sources, some of which may not be known. Crossbreeds are popular, due to the belief that they have increased vigor without loss of attractiveness of the dog. Certain planned crossbreeding between purebred dogs of different breeds are now widely known as "designer dogs" and can produce puppies worth more than their purebred parents, due to a high demand.

Horses

Crossbreeding in horses is often done with the intent of ultimately creating a new breed of horse. One type of modern crossbreeding in horses is used to create many of the

warmblood Warmbloods are a group of middle-weight horse types and breeds primarily originating in Europe and registered with organizations that are characterized by open studbook policy, studbook selection, and the aim of breeding for equestrian sport. ...

breeds. Warmbloods are a type of horse used in the

sport horse A sport horse or sporthorse is a type of horse, rather than any particular breed. The term is usually applied to horses bred for the traditional Olympic equestrian sporting events of dressage, eventing, show jumping, and combined driving, but ...

disciplines, usually registered in an

open stud book A breed registry, also known as a herdbook, studbook or register, in animal husbandry and the hobby of animal fancy