Mongrel

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A mongrel dog. DNA Sequencing shows heritage of Boxer, American Pit Bull, Great Dane, and others Mongrel 1.jpg
A mongrel dog. DNA Sequencing shows heritage of Boxer, American Pit Bull, Great Dane, and others

A mongrel, mutt, or mixed-breed dog is a dog that does not belong to one officially recognized breed, including those that result from intentional breeding. Although the term mixed-breed dog is sometimes preferred, many mongrels have no known purebred ancestors.

Contents

Crossbreed dogs, and "designer dogs", while also a mix of breeds, differ from mongrels in being intentionally bred. At other times, the word mongrel has been applied to informally purpose-bred dogs such as curs, which were created at least in part from mongrels, especially if the breed is not officially recognized.

Although mongrels are viewed as of less commercial value than intentionally bred dogs, they are thought to be less susceptible to genetic health problems associated with inbreeding (based on the theory of heterosis), and have enthusiasts and defenders who prefer them to intentionally bred dogs.

Estimates place the prevalence of mongrels at 150 million animals worldwide. [1]

Terminology

Crossbreed v mongrel

In the United States, the term mixed-breed is a favored synonym over mongrel among individuals who wish to avoid negative connotations associated with the latter term. [2] The implication that such dogs must be a mix of defined breeds may stem from an inverted understanding of the origins of dog breeds. Purebred dogs have been, for the most part, artificially created from random-bred populations by human selective breeding with the purpose of enhancing desired physical, behavioral, or temperamental characteristics. Dogs that are not purebred are not necessarily a mix of such defined breeds. [3] Therefore, among some experts and fans of such dogs, mongrel is still the preferred term. [4] [5] [6] [7]

Dog crossbreeds, sometimes called designer dogs, also are not members of a single recognized breed. Unlike mixed-breeds, crossbreed dogs are often the product of artificial selection – intentionally created by humans, whereas the term mongrel specifically refers to dogs that develop by natural selection, without the planned intervention of humans.

A mutt with a heavy, counter-shaded winter coat Poligraf Poligrafovich.JPG
A mutt with a heavy, counter-shaded winter coat

Regional and slang terms

The words cur, [8] tyke, [9] mutt, and mongrel [10] are used, sometimes in a derogatory manner. There are also regional terms for mixed-breed dogs. In the United Kingdom, mongrel is the unique technical word for a mixed-breed dog. North Americans generally prefer the term mix or mixed-breed. Mutt [11] is also commonly used (in the United States and Canada). Some American registries and dog clubs that accept mixed-breed dogs use the breed description All American.

There are also names for mixed-breeds based on geography, behavior, or food. In Hawaii, mixes are referred to as poi dogs, although they are not related to the extinct Hawaiian Poi Dog. In the Bahamas and the Turks and Caicos Islands, the common term is potcake dogs (referring to the table scraps they are fed). In South Africa, the tongue-in-cheek expression pavement special is sometimes used as a description for a mixed-breed dog. In Trinidad and Tobago, these mixed dogs are referred to as pot hounds (pothong). In Serbia, a similar expression is prekoplotski avlijaner (over-the-fence yard-dweller). In Russia, a colloquial term дворняга (yard-dweller) is used most commonly. In the Philippines, mixed-breed street dogs are often called askal , a Tagalog-derived contraction of asong kalye (”street dog"). In Puerto Rico, they are known as satos ; in Venezuela they are called yusos or cacris, the latter being a contraction of the words callejero criollo (literally, street creole, as street dogs are usually mongrels); and in Chile and Bolivia, they are called quiltros. In Costa Rica, it is common to hear the word zaguate, a term originating from a Nahuatl term, zahuatl, that refers to the disease called scabies. In the rural southern United States, a small hunting dog is known as a feist.

Slang terms are also common. Heinz 57 , Heinz, or Heinz Hound is often used for dogs of uncertain ancestry, in a playful reference to the "57 Varieties" slogan of the H. J. Heinz Company. In some countries, such as Australia, bitsa (or bitzer) is sometimes used, meaning "bits o' this, bits o' that". In Brazil and the Dominican Republic, the name for mixed-breed dogs is vira-lata (trash-can tipper) because of homeless dogs who knock over trash cans to reach discarded food. In Newfoundland, a smaller mixed-breed dog is known as a cracky, hence the colloquial expression "saucy as a cracky" for someone with a sharp tongue.

Determining ancestry

This Golden Retriever/ German Shepherd mix dog has more average mongrel traits than of either parents' breed. MuttShepherdRetriever 72.jpg
This Golden Retriever/ German Shepherd mix dog has more average mongrel traits than of either parents' breed.

Guessing a mixed-breed's ancestry can be difficult even for knowledgeable dog observers, because mixed-breeds have much more genetic variation than purebreds. For example, two black mixed-breed dogs might each have recessive genes that produce a blond coat and, therefore, produce offspring looking unlike their parents.

Starting in 2007, genetic analysis [12] has become available to the public. The companies claim their DNA-based diagnostic test can genetically determine the breed composition of mixed-breed dogs. These tests are still limited in scope because only a small number of the hundreds of dog breeds have been validated against the tests, and because the same breed in different geographical areas may have different genetic profiles. The tests do not test for breed purity, but for genetic sequences that are common to certain breeds. With a mixed-breed dog, the test is not proof of purebred ancestry, but rather an indication that those dogs share common ancestry with certain purebreds. The American Kennel Club does not recognize the use of DNA tests to determine breed. [13] [14]

Many newer dog breeds can be traced back to a common foundational breed, making them difficult to separate genetically. For example, Labrador Retrievers, Flat-coated Retrievers, Chesapeake Bay Retrievers, and Newfoundland dogs share a common ancestry with the St. John's water dog – a now-extinct naturally occurring dog landrace from the island of Newfoundland.

Health

Six-year old female American Pit Bull Terrier and Labrador mix Female pitador.jpg
Six-year old female American Pit Bull Terrier and Labrador mix

The theory of hybrid vigor suggests that as a group, dogs of varied ancestry will be generally healthier than their purebred counterparts. In purebred dogs, intentionally breeding dogs of very similar appearance over several generations produces animals that carry many of the same alleles, some of which are detrimental. If the founding population for the breed was small, then the genetic diversity of that particular breed may be small for quite some time.

When humans select certain dogs for new breeds, they artificially isolate that group of genes and cause more copies of that gene to be made than might have otherwise occurred in nature. The population is initially more fragile because of the lack of genetic diversity. If the dog breed is popular, and the line continues, over hundreds of years diversity increases due to mutations and occasional out-breeding. This is why some of the very old breeds are more stable. One issue is when certain traits found in the breed standard are associated with genetic disorders. The artificial selective force favors the duplication of the genetic disorder because it comes with a desired physical trait. [15] [16] The genetic health of hybrids tends to be higher. [17] Healthy traits have been lost in many purebred dog lines because many breeders of showdogs are more interested in conformation – the physical attributes of the dogs in relation to the breed standard – than in the health and working temperament for which the dog was originally bred. [18]

Populations are vulnerable when the dogs bred are closely related. Inbreeding among purebreds has exposed various genetic health problems not always readily apparent in less uniform populations. Mixed-breed dogs are more genetically diverse due to the more haphazard nature of their parents' mating. The offspring of such matings might be less likely to express certain genetic disorders because there might be a decreased chance that both parents carry the same detrimental recessive alleles, but some deleterious recessives occur across many seemingly unrelated breeds, and therefore merely mixing breeds is no guarantee of genetic health. When two poor specimens are bred, the offspring could inherit the worst traits of both parents. This is commonly seen in dogs that came from puppy mills. [19]

Several studies have shown that mixed-breed dogs have a health advantage over purebred dogs. A German study finds that "mongrels require less veterinary treatment". [20] Studies in Sweden have found that "Mongrel dogs are less prone to many diseases than the average purebred dog" [21] and, when referring to death rates, that "mongrels were consistently in the low risk category". [22] Data from Denmark also suggest that mixed breeds have greater longevity on average compared to purebreds. [23] A British study showed similar results, but a few breeds (notably Jack Russell Terriers, Miniature Poodles and Whippets) lived longer than mixed breeds. [24]

In one study, the effect of breed on longevity in the pet dog was analyzed using mortality data from 23,535 pet dogs. The data were obtained from North American veterinary teaching hospitals. The median age at death was determined for purebred and mixed-breed dogs of different body weights. Within each body weight category, the median age at death was lower for purebred dogs compared with mixed-breed dogs. The median age at death was "8.5 years for all mixed breed dogs, and 6.7 years for all pure breed dogs" in the study. [25]

In 2013, a study found that mixed breeds live on average 1.2 years longer than purebreds, and that increasing body weight was negatively correlated with longevity (i.e. the heavier the dog, the shorter its lifespan). [26] Another study published in 2019 confirmed this 1.2 year difference in lifespan for mixed-breed dogs, and further demonstrated negative impacts of recent inbreeding and benefits of occasional outcrossing for lifespan in individual dogs. [27]

Studies that have been done in the area of health show that mixed-breeds on average are both healthier and longer-lived than their purebred relations. This is because current accepted breeding practices within the pedigreed dog community result in a reduction in genetic diversity, and can result in physical characteristics that lead to health issues. [28]

Studies have shown that crossbreed dogs have a number of desirable reproductive traits. Scott and Fuller found that crossbreed dogs were superior mothers compared to purebred mothers, producing more milk and giving better care. These advantages led to a decreased mortality in the offspring of crossbreed dogs. [29]

Types

Mongrel dogs can be divided roughly into types:

Purebred dogs are known by breed names given to groups of dogs that are visibly similar in most characteristics and have reliable documented descent. [32] In recent years many owners and breeders of crossbreed dogs identify them—often facetiously—by invented names constructed from parts of the parents' breed names. These are known as portmanteau names and the resulting crosses as "designer dogs". For example, a cross between a Pekingese and a Poodle may be referred to as a Pekeapoo. Other similarly named crossbreeds include the Goldendoodle, a cross between a Standard Poodle and a Golden Retriever, and the Dorgi, a cross between a Dachshund and a Welsh Corgi.

In dog sports

A mixed-breed dog demonstrates dog agility. MixedBreedAgilityTunnel wb.jpg
A mixed-breed dog demonstrates dog agility.

Until the early 1980s, mixed-breed dogs were usually excluded from obedience and other dog sport competitions. However, starting with the American Mixed Breed Obedience Registry (AMBOR) and the Mixed Breed Dog Clubs of America (MBDCA), which created obedience venues in which mixed-breed dogs could compete, more opportunities have opened up for all dogs in all dog sports. Most dog agility and fly ball organizations have always allowed mixed-breed dogs to compete. Today, mixed-breeds have proven their worth in many performance sports.

In conformation shows, where dogs' conformation to a breed standard is evaluated, mixed-breed dogs normally cannot compete. For purebred dogs, their physical characteristics are judged against a single breed standard. This is different in the case of mixed-breed dogs because they are difficult to classify, except for height. There is variation in physical traits such as coat, skeletal structure, gait, ear set, eye shape and color. When conformation standards are applied to mixed-breed dogs, such as in events run by the MBDCA, the standards are usually general traits of health, soundness, symmetry, and personality.

The Kennel Club (U.K.) operates a show called Scruffts (a name derived from its prestigious Crufts show) open only to mixed-breeds in which dogs are judged on character, health, and temperament. Some kennel clubs, whose purpose is to promote purebred dogs, still exclude mixed-breeds from their performance events. The AKC and the FCI are two such prominent organizations. While the AKC does allow mixed-breed dogs to earn their Canine Good Citizen award, mixed-breed dogs are not permitted to enter AKC "all breed" events, though through their "Canine Partners" program, mixed-breed dogs can be registered to compete in AKC Agility, Obedience, and Rally events.

See also

Related Research Articles

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<span class="mw-page-title-main">Dog breed</span> Group of closely related and visibly similar domestic dogs

A dog breed is a particular type of dog that was purposefully bred by humans to perform specific tasks, such as herding, hunting, and guarding. Dogs are the most variable mammal on Earth, with artificial selection producing upward of 360 globally recognized breeds. These breeds possess distinct traits related to morphology, which include body size, skull shape, tail phenotype, fur type, body shape, and coat colour. However, there is only one species of dog. Their behavioral traits include guarding, herding, and hunting, and personality traits such as hyper-social behavior, boldness, and aggression. Most breeds were derived from small numbers of founders within the last 200 years. As a result of their adaptability to many environments and breedability for human needs, today dogs are the most abundant carnivore species and are dispersed around the world.

<span class="mw-page-title-main">American Kennel Club</span> American purebreed dog registry

The American Kennel Club (AKC) is a registry of purebred dog pedigrees in the United States. In addition to maintaining its pedigree registry, this kennel club also promotes and sanctions events for purebred dogs, including the Westminster Kennel Club Dog Show, an annual event which predates the official forming of the AKC, the National Dog Show and the AKC National Championship. The AKC is a non-member partner with the Fédération Cynologique Internationale. The AKC recognizes 200 dog breeds, as of 2022.

<span class="mw-page-title-main">Staffordshire Bull Terrier</span> British breed of dog

The Staffordshire Bull Terrier, also called the Staffy or Stafford, is a purebred dog of small to medium size in the terrier group that originated in the northern parts of Birmingham and in the Black Country of Staffordshire, for which it is named. They descended from 19th-century bull terriers that were developed by crossing bulldogs with various terriers to create a generic type of dog generally known as bull and terriers. Staffords share the same ancestry with the modern Bull Terrier, although the two breeds developed along independent lines, and do not resemble each other. Modern Staffords more closely resemble the old type of bull terrier, and were first recognised as a purebred dog breed by The Kennel Club of Great Britain in 1935.

<span class="mw-page-title-main">Alaskan Malamute</span> Dog breed

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<span class="mw-page-title-main">Flat-coated Retriever</span> Dog breed

The Flat-coated Retriever is a gun dog breed originating from England. It was developed as a retriever both on land and in the water.

<span class="mw-page-title-main">Dog show</span> Competitive exhibition of dogs

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<span class="mw-page-title-main">Dog breeding</span> Mating selected dogs for specific qualities

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<span class="mw-page-title-main">Goldendoodle</span> Dog breed

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<span class="mw-page-title-main">Labradoodle</span> Crossbreed dog

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<span class="mw-page-title-main">Dog crossbreed</span> Dog type

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A crossbreed is an organism with purebred 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 purebred gene pool to the point of extinction of a given breed of organism.

<span class="mw-page-title-main">Boykin Spaniel</span> Dog breed

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<span class="mw-page-title-main">Bull and terrier</span> Mixed breed

Bull and terrier was a common name for crossbreeds between bulldogs and terriers in the early 1800s. Other names included half-and-halfs and half-breds. It was a time in history when, for thousands of years, dogs were classified by use or function, unlike the modern pets of today that were bred to be conformation show dogs and family pets. Bull and terrier crosses were originally bred to function as fighting dogs for bull- and bear-baiting, and other popular blood sports during the Victorian era. The sport of bull baiting required a dog with attributes such as tenacity and courage, a wide frame with heavy bone, and a muscular, protruding jaw. By crossing bulldogs with various terriers from Ireland and Great Britain, breeders introduced "gameness and agility" into the hybrid mix.

<span class="mw-page-title-main">Dalmatian dog</span> Dog breed

The Dalmatian is a breed of dog with a white coat marked with dark-coloured spots. Originally bred as a hunting dog, it was also used as a carriage dog in its early days. The origins of this breed can be traced back to present-day Croatia and its historical region of Dalmatia. It is thought that early ancestors of the breed were certain breeds of pointers and a spotted Great Dane. Today, it is a popular pet and many enthusiasts enter Dalmatians into kennel club competitions.

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The Golden Retriever is a Scottish breed of retriever dog of medium size. It is characterised by a gentle and affectionate nature and a striking golden coat. It is commonly kept as a pet and is among the most frequently registered breeds in several Western countries. It is a frequent competitor in dog shows and obedience trials; it is also used as a gun dog and may be trained for use as a guide dog.

<span class="mw-page-title-main">Popular sire effect</span>

The popular sire effect occurs when an animal with desirable attributes is bred repeatedly. In dog breeding, a male dog that wins respected competitions becomes highly sought after, as breeders believe the sire possesses the genes necessary to produce champions. However, the popular sire effect is not just down to wanting to produce a champion. For example, in Staffordshire Bull Terriers there are several popular sires who are used by breeders to produce specific colours that are not favoured in the show ring. The popular sire is often bred extensively with many females. This can cause undetected, undesirable genetic traits in the stud to spread rapidly within the gene pool. It can also reduce genetic diversity by the exclusion of other males.

<span class="mw-page-title-main">Chihuahua (dog breed)</span> Mexican breed of dog

The Chihuahua is a Mexican breed of toy dog. It is named for the Mexican state of Chihuahua and is among the smallest of all dog breeds. It is usually kept as a companion animal or for showing.

Purebred breeders are dog breeders that intentionally breed purebred dogs specifically to continue the lineage of certain breed characteristics in dogs by mating selected canines.

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