Amongrel,mutt,ormixed-breed dogis adogthat does not belong to one officially recognizedbreed,including those that result from intentionalbreeding.Although the termmixed-breed dogis sometimes preferred, many mongrels have no known purebred ancestors.
Crossbreeddogs, and "designer dogs",while also a mix ofbreeds,differ from mongrels in being intentionally bred. At other times, the wordmongrelhas been applied to informally purpose-bred dogs such ascurs,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 withinbreeding(based on the theory ofheterosis), and have enthusiasts and defenders who prefer them to intentionally bred dogs.
Estimates place the prevalence of mongrels at 150 million animals worldwide.[1]
In the United States, the termmixed-breedis a favored synonym overmongrelamong individuals who wish to avoid negativeconnotationsassociated 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 notpurebredare not necessarily a mix of such defined breeds.[3]Therefore, among some experts andfansof such dogs,mongrelis still the preferred term.[4][5][6][7]
Dog crossbreeds,sometimes calleddesigner dogs,also are not members of a single recognized breed. Unlike mixed-breeds, crossbreed dogs are often the product ofartificial selection– intentionally created by humans, whereas the termmongrelspecifically refers to dogs that develop bynatural selection,without the planned intervention of humans.
The wordscur,[8]tyke,[9]mutt,andmongrel[10]are used, sometimes in a derogatory manner. There are also regional terms for mixed-breed dogs. In theUnited Kingdom,mongrelis the unique technical word for a mixed-breed dog. North Americans generally prefer the termmixormixed-breed.Mutt[11]is also commonly used in theUnited StatesandCanada.Some American registries and dog clubs that accept mixed-breed dogs use the termAll-Americanto describe mixed-breed dogs.[12]
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 extinctHawaiian Poi Dog.In theBahamasand theTurks and Caicos Islands,the common term ispotcake dogs(referring to the table scraps they are fed). In South Africa, the tongue-in-cheek expressionpavement specialis sometimes used as a description for a mixed-breed dog. InTrinidad and Tobago,these mixed dogs are referred to aspot hounds(pothong). InSerbia,a similar expression isprekoplotski avlijaner(over-the-fence yard-dweller). InRussia,a colloquial termдворняга(yard-dweller) is used most commonly. In thePhilippines,mixed-breed street dogs are often calledaskal,aTagalog-derived contraction ofasong kalye(” street dog "). InPuerto Rico,they are known assatos;inVenezuelathey are calledyusosorcacris,the latter being a contraction of the wordscallejero criollo(literally, street creole, as street dogs are usually mongrels); and inChileandBolivia,they are calledquiltros.InCosta Rica,it is common to hear the wordzaguate,a term originating from aNahuatlterm,zahuatl,that refers to the disease calledscabies.In the rural southern United States, a small hunting dog is known as afeist.
Slangterms 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"sloganof theH. J. Heinz Company.In some countries, such as Australia,bitsa(orbitzer) is sometimes used, meaning "bits o' this, bits o' that". InBraziland theDominican Republic,the name for mixed-breed dogs isvira-lata(trash-can tipper) because of homeless dogs who knock over trash cans to reach discarded food. InNewfoundland,a smaller mixed-breed dog is known as acracky,hence the colloquial expression "saucy as a cracky" for someone with a sharp tongue.
Guessing a mixed-breed's ancestry can be difficult even for knowledgeable dog observers, because mixed-breeds have much moregeneticvariation than purebreds. For example, two black mixed-breed dogs might each haverecessive genesthat produce a blond coat and, therefore, produce offspring looking unlike their parents.
Starting in 2007, genetic analysis[13]has become available to the public. The companies claim theirDNA-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. TheAmerican Kennel Clubdoes not recognize the use of DNA tests to determine breed.[14][15]
The theory ofhybrid vigorsuggests 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 samealleles,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.[16][17]The genetic health of hybrids tends to be higher.[18]Healthy traits have been lost in many purebred dog lines because many breeders ofshowdogsare 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.[19]
Populations are vulnerable when the dogs bred are closely related.Inbreedingamong 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 suchmatingsmight 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 somedeleteriousrecessives 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 frompuppy mills.[20]
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".[21]Studies in Sweden have found that "Mongrel dogs are less prone to many diseases than the average purebred dog"[22]and, when referring to death rates, that "mongrels were consistently in the low risk category".[23]Data from Denmark also suggest that mixed breeds have greater longevity on average compared to purebreds.
[24]A British study showed similar results, but a few breeds (notablyJack Russell Terriers,Miniature PoodlesandWhippets) lived longer than mixed breeds.[25]
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.[26]
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).[27]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.[28]
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.[29]
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.[30]
A small mongrel displaying characteristics of three breedsMixes that show characteristics of two or more breeds. A mix might have some purebred ancestors, or might come from a long line of mixed-breeds. These dogs are usually identified by the breed they most resemble, such as a "Lab mix" or "Collie-Shepherd", even if their ancestry is unknown.
The genericpariah dog,or feralCanis lupus familiaris,where non-selective breeding has occurred over many generations. The term originally referred to the wild dogs of India, but now refers to dogs belonging to or descended from a population of wild or feral dogs.[citation needed]TheCanaan Dogis an example of a recognized breed with pariah ancestry. Pariah dogs tend to be between yellow and light brown in color and of medium height and weight. This may represent the appearance of the modern dog's ancestor. DNA analysis has shown pariah dogs to have a more ancient gene pool than modern breeds.[31]
Functional breeds, which are purpose-bred dogs whose ancestors are not purebred, but rather are selected by their performance at particular tasks. Examples of this are theAlaskan husky,the Eurohound, and the Pointer/Greyhound mixes referred to as Greysters, which compete atskijoringandpulkaraces, particularly in Europe. Occasionally, a functional breed such as this becomes accepted as a breed over time.
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 asportmanteaunames and the resulting crosses as "designer dogs". For example, a cross between aPekingeseand aPoodlemay be referred to as a Pekeapoo. Other similarly named crossbreeds include theGoldendoodle,a cross between a Standard Poodle and a Golden Retriever, and theDorgi,a cross between aDachshundand aWelsh Corgi.
Until the early 1980s, mixed-breed dogs were usually excluded fromobedienceand otherdog sportcompetitions. However, starting with the American Mixed Breed Obedience Registry (AMBOR) and theMixed 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.
Inconformation shows,where dogs' conformation to abreed standardis 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 toclassify,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 calledScruffts(a name derived from its prestigiousCruftsshow) open only to mixed-breeds in which dogs are judged on character, health, and temperament. Somekennel clubs,whose purpose is to promote purebred dogs, still exclude mixed-breeds from their performance events. TheAKCand theFCIare two such prominent organizations. While the AKC does allow mixed-breed dogs to earn theirCanine Good Citizenaward, 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.
^Morris, Desmond (2008)."Feral dogs".Dogs: The Ultimate Dictionary of over 1,000 Dog Breeds(First Paperback ed.). Vermont: Tralfalgar Square. pp. 696–697.ISBN978-1-57076-410-3.The mongrel is not a true breed, but it is certainly a common category of domestic dog. It has been estimated that, worldwide, there are 150 million of them.
^Witiak, Dr. Gene (2004).True Confessions of a Veterinarian.Glenbridge Publishing Ltd. p. 11.ISBN978-0-944435-54-0.Canines of unknown lineage used to be termed mongrels—how demeaning! Over time, the term 'mixed breed' was preferred.
^Dlugosch, K. M.; Parker, I. M. (2008). "Founding events in species invasions: Genetic variation, adaptive evolution, and the role of multiple introductions".Molecular Ecology.17(1): 431–49.doi:10.1111/j.1365-294X.2007.03538.x.PMID17908213.S2CID15359463.
^McGreevy, P.D.; Nicholas, W.F. (1999). "Some Practical Solutions to Welfare Problems in Pedigree Dog Breeding".Animal Welfare.8:329–331.doi:10.1017/S0962728600021965.S2CID255889459.Hybrids have a far lower chance of exhibiting the disorders that are common with the parental breeds. Their genetic health will be substantially higher. (p. 338)
^Beythien, R. (1998)Tierarten- und Hunderassenverteilung, Erkrankungshäufigkeit und prophylaktische Maßnahmen bei den häufigsten Hunderassen am Beispiel einer Tierarztpraxis in Bielefeld in den Jahren 1983–1985 und 1990–1992,Diss., Tierärztl. Hochschule Hannover
^Egenvall, A; Bonnett, B. N.; Olson, P; Hedhammar, A (2000). "Gender, age, breed and distribution of morbidity and mortality in insured dogs in Sweden during 1995 and 1996".The Veterinary Record.146(18): 519–25.doi:10.1136/vr.146.18.519.PMID11321213.S2CID24303176.
^Bonnett, B. N.; Egenvall, A.; Olson, P.; Hedhammar, A. (1997). "Mortality in insured Swedish dogs: Rates and causes of death in various breeds".Veterinary Record.141(2): 40–4.doi:10.1136/vr.141.2.40.PMID9253830.S2CID9721674.
^Proschowsky, H. F.; Rugbjerg, H.; Ersbøll, A. K. R. (2003). "Mortality of purebred and mixed-breed dogs in Denmark".Preventive Veterinary Medicine.58(1–2): 63–74.doi:10.1016/S0167-5877(03)00010-2.PMID12628771.
^Michell, A. R. (1999). "Longevity of British breeds of dog and its relationships with sex, size, cardiovascular variables and disease".The Veterinary Record.145(22): 625–9.doi:10.1136/vr.145.22.625.PMID10619607.S2CID34557345.
DNA sequencingshowed this mongrel dog to be a mix ofLabrador Retriever,Bull Mastiff,Chow,Australian Cattle Dog,Corgi,andPit Bull.
Spinone Italiano–German Shepherdmixed-breed dog
Australian Shepherd–Border Colliemixed-breed dog
Although these mongrels arelittermatesof anAustralian Shepherdmother, they look quite different and neither exactly resembles that breed.
A Mexican street mutt
Mongrel of visually indeterminable lineage
Mid-size Brazilian mixed-breed dog
A two-year-old dog of unknown parentage, possibly Australian Shepherd andGolden Retriever
Ukrainian mixed-breed dog
Askalalso known asAspinis a street dog that is commonly seen in thePhilippines
A mongrel dog withGerman Shepherd,Shetland Sheepdog,American Staffordshire Terrier,Chow Chowheritage and others
Media related toMixed-breed dogsat Wikimedia Commons
