Dog breed in the context of Pure breed

The dog (Canis familiaris or Canis lupus familiaris) is a domesticated descendant of the gray wolf. Also called the domestic dog, it was selectively bred from a population of wolves during the Late Pleistocene by hunter-gatherers. Dogs were the first species to be domesticated over 14,000 years ago, before the development of agriculture. Due to their long association with humans, dogs have gained the ability to thrive on a starch-rich diet that would be inadequate for other canids.

Dogs have been bred for desired behaviors, sensory capabilities, and physical attributes. Dog breeds vary widely in shape, size, and color. They have the same number of bones (with the exception of the tail), powerful jaws that house around 42 teeth, and well-developed senses of smell, hearing, and sight. Compared to humans, dogs possess a superior sense of smell and hearing, but inferior visual acuity. Dogs perform many roles for humans, such as hunting, herding, pulling loads, protection, companionship, therapy, aiding disabled people, and assisting police and the military.

The dachshund (UK: /ˈdækshʊnd, -ənd, -hʊnt/ DAKS-huund, -⁠ənd, -⁠huunt or US: /ˈdɑːkshʊnt, -hʊnd, -ənt/ DAHKS-huunt, -⁠huund, -⁠ənt; German: 'badger dog'), also known as the wiener dog, or sausage dog, badger dog, doxen and doxie, is a short-legged, long-bodied, hound-type dog breed. The dog may be smooth-haired, wire-haired, or long-haired, with varied coloration.

The dachshund was bred to scent, chase, and flush out badgers and other burrow-dwelling animals. The miniature dachshund was bred to hunt small animals such as rabbits.

The Chihuahua or Spanish: Chihuahueño is a Mexican breed of toy dog. It is named after the Mexican state of Chihuahua and is one of the smallest dog breeds in the world. It is usually kept as a companion animal.

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.

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.

A herding dog, also known as a stock dog or working dog, is a type of dog that either has been trained in herding livestock or belongs to one of the breeds that were developed for herding. A dog specifically trained to herd sheep is known as a sheep dog or shepherd dog, and one trained to herd cattle is known as a cattle dog or cow dog.

A police dog, also known as a K-9 (phonemic abbreviation of canine), is a dog that is trained to assist police and other law enforcement officers. Their duties may include searching for drugs and explosives, locating missing people, finding crime scene evidence, protecting officers and other people, and attacking suspects who flee from officers. The breeds most commonly used by law enforcement are the German Shepherd, Belgian Malinois, Bloodhound, Dutch Shepherd, and Labrador Retriever. In recent years, the Belgian Malinois has become the leading choice for police and military work due to their intense drive, focus, agility, and smaller size, though German Shepherds remain the breed most associated with law enforcement.

Police dogs are used on a federal and local level for law enforcement purposes in many parts of the world. They are often assigned to what in somenations is referred to as a K-9 Unit, with a specific handler, and must remember several verbal cues and hand gestures. Initial training for a police dog typically takes between eight months and a year, depending on where and how they are trained, and for what purpose. Police dogs often regularly take training programs with their assigned handler to reinforce their training. In many countries, intentionally injuring or killing a police dog is a criminal offense.

Dog anatomy comprises the anatomical study of the visible parts of the body of a domestic dog. Details of structures vary tremendously from breed to breed, more than in any other animal species, wild or domesticated, as dogs are highly variable in height and weight. The smallest known adult dog was a Yorkshire Terrier that stood only 6.3 cm (2.5 in) at the shoulder, 9.5 cm (3.7 in) in length along the head and body, and weighed only 113 grams (4.0 oz). The heaviest dog was an English Mastiff named Zorba, which weighed 314 pounds (142 kg). The tallest known adult dog is a Great Dane that stands 106.7 cm (42.0 in) at the shoulder.

The Golden Retriever is a Scottish breed of retriever dog of medium-large size. It is characterised by a gentle and affectionate nature and a striking golden coat. It is a working dog, and registration is subject to successful completion of a working trial. It is commonly kept as a companion dog and is among the most frequently registered breeds in several Western countries; some may compete in dog shows or obedience trials, or work as guide dogs.

The Golden Retriever was bred by Sir Dudley Marjoribanks at his Scottish estate Guisachan in the late nineteenth century. He cross-bred Flat-coated Retrievers with Tweed Water Spaniels, with some further infusions of Red Setter, Labrador Retriever and Bloodhound. It was recognised by the Kennel Club in 1913, and during the interwar period spread to many parts of the world.

The Welsh Springer Spaniel (Welsh: Llamgi Cymru or Tarfgi Cymru) is a breed of dog and a member of the spaniel family. Thought to be comparable to the old Land Spaniel, they are similar to the English Springer Spaniel and historically have been referred to as both the Welsh Spaniel and the Welsh Cocker Spaniel. They were relatively unknown until a succession of victories in dog trials by the breed increased its popularity. Following recognition by The Kennel Club in 1902, the breed gained the modern name of Welsh Springer Spaniel. The breed's coat only comes in a single colour combination of white with red markings, usually in a piebald pattern. Loyal and affectionate, they can become very attached to family members and are wary of strangers. Health conditions are limited to those common among many breeds of dog, although they are affected more than average by hip dysplasia and some eye conditions. They are a working dog, bred for hunting, and while not as rare as some varieties of spaniel, they are rarer than the more widely known English Springer Spaniel with which they are sometimes confused.

A dog bite is a bite upon a person or other animal by a dog. More than one successive bite is often called a dog attack, although dog attacks can include knock-downs and scratches. Though some dog bites do not result in injury, they can result in infection, disfigurement, temporary or permanent disability, or death. Another type of dog bite is the "soft bite" displayed by well-trained dogs, by puppies, and in non-aggressive play. Dog bites can occur during dog fighting, as a response to mistreatment, by trained dogs working as guard, police or military animals, or during a random encounter.

There is debate on whether or not certain breeds of dogs are inherently more prone to commit attacks causing serious injury (i.e., so driven by instinct and breeding that, under certain circumstances, they are exceedingly likely to attempt or commit dangerous attacks). It is recognized that the risk of dog bites can be increased by human actions such as abuse or bite training, or through inaction such as neglect, carelessness in confinement or lack of control.

A mongrel, mutt, or mixed-breed dog is any dog which does not belong to one officially recognized breed. While such terms may refer to all dogs of mixed breeds, the terms "dog crossbreed" and "designer dog" specifically refer to mixed-breed dogs which are intentionally bred.

Mixed-breed dogs may have ancestries that include any combination of purebred dogs and other mongrels.

This list of dog breeds includes both extant and extinct dog breeds, varieties and types. A research article on dog genomics published in Science/AAAS defines modern dog breeds as "a recent invention defined by conformation to a physical ideal and purity of lineage".

According to BigThink, over 40% of the world's dog breeds come from the United Kingdom, France and Germany. It states: "Great Britain and France are the ground zero of dog fancying, with 57 registered breeds each. Germany is not far behind, with 47 breeds. These three countries alone represent more than 40% of all dog breeds recognized by the Fédération Cynologique Internationale."

Toy dog traditionally refers to a very small dog or a grouping of small and very small breeds of dog. A toy dog may be of any of various dog types. Types of dogs referred to as toy dogs may include spaniels, pinschers and terriers that have been bred down in size. Not all toy dogs are lap dogs.

The Boxer is a medium to large, short-haired dog breed of mastiff-type, developed in Germany. The coat is smooth and tight-fitting; colors are fawn or brindled, with or without white markings. Boxers are brachycephalic (they have broad, short skulls), have a square muzzle, mandibular prognathism (an underbite), very strong jaws, and a powerful bite ideal for hanging on to large prey. The Boxer was bred from the Old English Bulldog and the now extinct Bullenbeisser, which became extinct by crossbreeding rather than by a decadence of the breed. The Boxer is a member of both The Kennel Club and American Kennel Club (AKC) Working Group.

The first Boxer club was founded in 1895, with Boxers being first exhibited in a dog show for St. Bernards in Munich the next year. Based on 2013 AKC statistics, Boxers held steady as the seventh-most popular breed of dog in the United States for the fourth consecutive year. According to the AKC's website, though, the boxer is now the 11th-most popular dog breed in the United States.

The American Pit Bull Terrier (APBT) is a dog breed recognized by the United Kennel Club (UKC) and the American Dog Breeders Association (ADBA), but not the American Kennel Club (AKC). It is a medium-sized, short-haired dog, of a solid build, whose early ancestors came from England. When compared with the English Staffordshire Bull Terrier, the American Pit Bull Terrier is larger by margins of 6–8 inches (15–20 cm) in height and 25–35 pounds (11–16 kg) in weight. The American Pit Bull Terrier varies in size: males are normally about 18–21 inches (45–53 cm) in height and around 35–60 pounds (15–27 kg) in weight, while females are normally around 17–20 inches (43–50 cm) in height and 30–50 pounds (13–22 kg) in weight.

According to the ADBA, the American Pit Bull is described to be medium-sized and has a short coat and smooth well-defined muscle structure, and its eyes are to be round to almond-shaped, and its ears are to be small to medium in length, typically half prick or rose in carriage. The tail is prescribed to be slightly thick and tapering to a point. The coat is required by the ADBA to be glossy, smooth, short, and stiff to the touch. Many colors, color patterns, and combinations of colors are acceptable to the ADBA, except that both the ADBA and UKC do not recognize merle coloring. Color patterns that are typical in the breed are solid and tuxedo.

Dog crossbreeds (sometimes called designer dogs) are dogs which have been crossbred or selectively bred from two or more recognized dog breeds. Generally considered a specific type of mixed-breed dog, dog crossbreeds are not recognised as breeds in their own right, and do not necessarily breed true. However, historic crossbreeding has led to established breeds, such as the Cesky Terrier.

Dog crossbreeds are combinations of lineages of the domestic dog; they are distinguished from canid hybrids, which are interspecific crosses between Canis species (wolves, coyotes, jackals, etc.).

The Irish Wolfhound (Irish: Cú Faoil) is a breed of large sighthound that has, by its presence and substantial size, inspired literature, poetry and mythology. One of the largest of all breeds of dog, the breed is used by coursing hunters who have prized it for its ability to dispatch game caught by other, swifter sighthounds. In 1902, the Irish Wolfhound was declared the regimental mascot of the Irish Guards.