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dog,carnivorous, domesticated wolfwolf,
carnivorous mammal of the genus Canis in the dog family. Once distributed over most of the Northern Hemisphere, wild wolves are now confined to the wilder parts of a reduced range.
..... Click the link for more information. (Canis lupus familiaris) of the family Canidae, to which the jackaljackal,
name for several Old World carnivorous mammals of the genus Canis, which also includes the dog and the wolf. Jackals are found in Africa and S Asia, where they inhabit deserts, grasslands, and brush country.
..... Click the link for more information. and foxfox,
carnivorous mammal of the dog family, found throughout most of the Northern Hemisphere. It has a pointed face, short legs, long, thick fur, and a tail about one half to two thirds as long as the head and body, depending on the species.
..... Click the link for more information. also belong. The family Canidae is sometimes referred to as the dog family, and its characteristics, e.g., long muzzle, large canine teeth, and long tail, as canine traits. However, the unmodified term dog usually refers only to the domestic subspecies Canis lupus familiaris.
Two characteristics distinguish the dog from other canids and, indeed, from all other animal species. The first is its worldwide distribution in close association with humans, encompassing both hemispheres from the tropics to the Arctic. The second is the enormous amount of variability found within the subspecies. For example, the Irish wolfhound may stand as high as 39 in. (99.1 cm) at the shoulder, while the Chihuahua's shoulder is usually no more than 6 in. (15.2 cm) from the ground; the silky coat of the Yorkshire terrier may be 2 ft (61 cm) long, while a few breeds of dog (such as the Mexican hairless) are entirely without hair. The evolution of such widely differing breeds has been heavily influenced by conscious human selection, in addition to natural evolution.
Dogs have been selectively bred through the centuries for special purposes, notably to pursue and retrieve game, as draft animals, as guides (e.g., for the blind), and as companions. Although dogs possess hearing abilities far superior to humans', their acute sense of smell is probably the sense most utilized. In addition to traditional hunting and tracking, the dog's sense of smell has been put to such diverse uses as the location of exotic foods and the detection of drugs and explosives, e.g., in luggage and packages.
Dogs can be protected against serious diseases for which vaccines are available; these include distemperdistemper,
in veterinary medicine, highly contagious, catarrhal, often fatal disease of dogs. It also affects wolves, foxes, mink, raccoons, and ferrets. Distemper is caused by a filtrable virus that is airborne; it is also spread by infected utensils, brushes, and clothing.
..... Click the link for more information. , canine hepatitis, leptospirosisleptospirosis
, febrile disease caused by bacteria of the genus Leptospirae. The disease may affect dogs, cattle, pigs, sheep, goats, and horses and is also transmissible to humans.
..... Click the link for more information. , and rabiesrabies
, acute viral infection of the central nervous system in dogs, foxes, raccoons, skunks, bats, and other animals, and in humans. The virus is transmitted from an animal to a person, or from one animal to another, via infected saliva, most often by
..... Click the link for more information. .
The dog is descended from the wolf. True wolves appeared in Europe about one million years ago and in the Americas some 700,000 years later. Dog remains estimated to be about 14,000 years old have been found in Germany, and younger remains have been found in Israel (about 13,500 years old) and Idaho (about 10,500 years old). It is probable that the dog was the first animal to become domesticated, certainly by 15,000 years ago, but possibly long before that. Genetic studies comparing dogs with surviving and extinct wolf species indicate that wolves and dogs separated 27,000 to 40,000 years ago, with the implication that domestication may have occurred as early as 30,000 years ago. Domestication may have occurred independently in a number of different areas of the world, but genetic tests show that all dogs are descended from an Eurasian stock, even the now extinct pre-Columbian dogs of the Americas.
It is thought that the earliest domesticated dogs resembled the present-day dingodingo
, wild dog (Canis lupus dingo) of Australia, believed to have been introduced thousands of years ago from SE Asia by the aboriginal settlers of that continent; currently regarded as a subspecies of the gray wolf.
..... Click the link for more information. , the wild dog of Australia. The dingo is believed to have come to Australia as a domestic dog with the aborigines from Southeast Asia. Although more historical information exists on the forerunners of European dogs (such as the British hounds, terriers, and shepherd dogs) than on those of other areas, there is evidence that dogs have existed in most areas of the world throughout the period of recorded history. One of the oldest known breeds is the basenjibasenji
, breed of medium-sized hound whose origins can be traced back several thousand years to Africa and the courts of the Egyptian pharaohs. It stands about 17 in. (43.2 cm) high at the shoulders and weighs about 23 lb (10.4 kg).
..... Click the link for more information. , which originated in central Africa and is still used as a hunter by certain tribes in that region. Several distinct breeds were known in ancient Egypt and a mastifflike breed (resembling the Kurdish dog in present-day Iraq) is found in Babylonian illustrations of c.2200 B.C.
The Purebred Dog
A breed of dog is produced by selecting and mating dogs with certain desired characteristics. The offspring of such matings are then inbred, i.e., mated with litter mates or close relatives. After about eight generations, the line usually breeds true, i.e., most offspring resemble each other. Then standard traits can be established for the new breed. A purebred dog is one that conforms to the standards of a certain breed and whose lineage, or pedigree, has been recorded for a certain period of time.
One of the principal functions of a kennel club is to maintain the records of lineage of individual purebred dogs in order to preserve breed standards. The stud books of the AKC contain entries for all purebred dogs whose owners have elected to register their dog's pedigree. Other stud books, such as those of the United Kennel Club, often record dogs of breeds not recognized by the AKC but which have a considerable following in the United States. Dogs of mixed origin or whose parentage is unknown are called mongrels.
Classification of Breeds
Attempts to classify dogs probably date from the time when humans discovered that certain canine traits were more useful than others. The earliest known system of classification, that of the Romans, included categories for house dogs, shepherd dogs, sporting dogs, war dogs, dogs that ran by scent, and dogs that ran by sight. Today there are systems of classification and breeding in most countries of Western Europe and in North America, many using a variation of the standard British system.
In the United States, the classification system most frequently encountered is that employed by the American Kennel Club (AKC), which recognizes more than 150 of the more than 200 known breeds. The breeds are grouped into six classes. In the sporting dogsporting dog,
classification used by breeders and kennel clubs to designate dogs bred for pointing, flushing, and retrieving game. These dogs hunt by air scent—as opposed to most hounds, which are ground scenters—and their quarry is primarily game birds.
..... Click the link for more information. group are pointerspointer,
breed of large sporting dog developed in England more than 300 years ago. It stands between 23 and 26 in. (58.4–66.4 cm) high at the shoulder and weighs between 50 and 60 lb (22.7–27.2 kg).
..... Click the link for more information. , retrievers, setters, and spaniels. These dogs hunt by air scent as opposed to those of the houndhound,
classification used by breeders and kennel clubs to designate dogs bred to hunt animals. Most of the dogs in this group hunt by scent, their quarry ranging from such large game as bear or elk to small game and vermin; ground scenters trail slowly with the head low, and
..... Click the link for more information. group, e.g., beaglesbeagle,
breed of small, compact hound developed over centuries in England and introduced into the United States in the 1870s. It stands between 10 and 15 in. (25.4–38.1 cm) high at the shoulder and weighs between 20 and 40 lb (9.1–18.1 kg).
..... Click the link for more information. , foxhounds, and bloodhoundsbloodhound,
breed of large hound whose ancestors were known in the Mediterranean region before the Christian era. It stands about 25 in. (63.5 cm) high at the shoulder and weighs between 80 and 110 lb (36.3–49.9 kg).
..... Click the link for more information. , which track their prey by ground scent. Also classified as hounds are those dogs of the greyhoundgreyhound,
breed of tall, swift, sight hound developed nearly 5,000 years ago in Egypt. It stands about 26 in. (66 cm) high at the shoulder and weighs about 65 lb (29.5 kg). Its short, smooth coat may be colored black, white, or various shades of fawn, brindle, blue, or red.
..... Click the link for more information. type, e.g., whippetswhippet,
breed of small, slender hound developed in England in the mid-18th cent. It stands between 18 and 22 in. (45.7–55.8 cm) high at the shoulder and weighs about 20 lb (9 kg). Its close-lying, smooth coat may be any color but is usually white, tan, or gray.
..... Click the link for more information. , borzoisborzoi
, breed of tall, swift hound developed in Russia in the early 17th cent., also called Russian wolfhound. It stands from 26 to 31 in. (66–81.2 cm) high at the shoulder and weighs about 85 lb (38.6 kg).
..... Click the link for more information. , and SalukisSaluki
, breed of tall, slender hound whose origins may be traced back to the Sumerian empire of 6000 B.C. It stands between 23 and 28 in. (58.4–71.1 cm) high at the shoulder, although females may reach only 18 in. (45.7 cm), and weighs between 45 and 60 lb (20.4–27.
..... Click the link for more information. , which hunt mainly by sight. The many breeds of terrierterrier,
classification used by breeders and kennel clubs to designate dogs originally bred to start small game and vermin from their burrows or, in the case of several breeds in this group, to go to earth and kill their prey. Today these dogs are raised chiefly as pets.
..... Click the link for more information. go to earth after their burrowing prey. Among the working dogworking dog,
classification used by breeders and kennel clubs to designate dogs raised by humans to herd cattle and sheep, as draft animals, as message dispatchers in wartime, in police and rescue work, as guardians of persons and property, or as guides (see guide dog) for the
..... Click the link for more information. group, used as guards, guides, and herders, are the colliecollie,
breed of large, agile working dog developed in Scotland during the 17th and 18th cent. It stands from 22 to 26 in. (55.9–66 cm) high at the shoulder and weighs from 50 to 75 lb (22.7–34 kg).
..... Click the link for more information. , the German shepherdGerman shepherd,
breed of large, muscular working dog perfected in Germany at the turn of the 20th cent. It stands about 25 in. (64 cm) high at the shoulder and weighs from 60 to 85 lb (27.2–38.5 kg).
..... Click the link for more information. , and the St. BernardSaint Bernard,
breed of massive working dog developed in Switzerland in the 18th cent. and perfected by British breeders during the 19th cent. It stands from 25 to 29 in. (64–74 cm) high at the shoulder and weighs from 140 to 170 lb (64–77 kg).
..... Click the link for more information. . Such diminutive pet dogs as the PekingesePekingese
, breed of small toy dog developed over many centuries in China. It stands from 6 to 9 in. (15.3–22.9 cm) high at the shoulder and weighs from 6 to 14 lb (2.7–6.4 kg).
..... Click the link for more information. , the PomeranianPomeranian
, breed of small, sturdy toy dog descended from the sledge dogs of Iceland and Lapland. It stands about 6 in. (15.3 cm) high at the shoulder and weighs from 3 to 7 lb (1.4–3.2 kg).
..... Click the link for more information. , and the pugpug,
breed of sturdy, compact toy dog that became popular in England during the 19th cent. It stands about 11 in. (27.9 cm) high at the shoulder and weighs from 14 to 18 lb (6.4–8.2 kg).
..... Click the link for more information. belong to the toy dogtoy dog,
classification used by breeders and kennel clubs to designate very small breeds of dogs kept as pets. Some are selectively bred diminutive forms of larger breeds and others are naturally small.
..... Click the link for more information. class. The nonsporting dognonsporting dog,
classification used by breeders and kennel clubs to designate dogs that may formerly have been bred to hunt or work but that are now raised chiefly as house pets and companions.
..... Click the link for more information. group is a class of dogs bred principally as pets and companions and includes the Boston terrierBoston terrier,
breed of small, lively nonsporting dog developed in the United States in the second half of the 19th cent. It stands between 14 and 17 in. (35.6–43.2 cm) high at the shoulder and weighs from 13 to 25 lb (5.9–11.3 kg).
..... Click the link for more information. , the bulldogbulldog,
breed of thick-set nonsporting dog developed in the British Isles many centuries ago. It stands from 13 to 15 in. (33–38.1 cm) high at the shoulder and weighs from 40 to 50 lb (18.1–22.7 kg).
..... Click the link for more information. , the chow chowchow chow,
breed of powerful nonsporting dog whose origins are obscure but whose development was accomplished many centuries ago in China. It stands from 18 to 20 in. (45.7–50.8 cm) high at the shoulder and weighs from 50 to 60 lb (22.7–27.2 kg).
..... Click the link for more information. , the DalmatianDalmatian
, breed of hardy, strong-bodied nonsporting dog probably developed in the Austrian province of Dalmatia (now Croatia) several hundred years ago. It stands from 19 to 23 in. (48.3–58.4 cm) high at the shoulder and weighs from 35 to 50 lb (15.9–22.7 kg).
..... Click the link for more information. , and the poodlepoodle,
popular breed of dog probably originating in Germany but generally associated with France, where it has been raised for centuries. There are three varieties, differing in size only.
..... Click the link for more information. . In addition to the breeds in the above classes, the AKC currently places additional breeds in a miscellaneous group; breeds recently recognized by the club are placed in this class until they become established. Included are the AkitaAkita
, breed of large dog developed in Japan from ancient ancestry and used originally as a hunter of such game as deer, wild boar, and bear. It stands from 20 to 27 in. (50.8–68.6 cm) high at the shoulder and weighs from 75 to 110 lb (34.1–49.9 kg).
..... Click the link for more information. of Japan, the Australian cattle dogAustralian cattle dog,
breed of medium-sized herding dog developed in Australia. It stands from 18 to 20 in. (45.7–50.8 cm) high at the shoulder and weighs about 33 lb (15 kg).
..... Click the link for more information. , the Australian kelpieAustralian kelpie,
breed of medium-sized sheepherding dog originating in Australia c.1870. It stands from 17 to 20 in. (43.2–50.8 cm) high at the shoulder and weighs from 25 to 30 lb (11.3–13.6 kg).
..... Click the link for more information. , the Bichon FriseBichon Frise
, breed of small dog developed in France after World War I. It stands from 8 to 12 in. (20–30 cm) high at the shoulder and has a profuse, silky coat that is loosely curled. It is solid white or white with apricot, cream, or gray markings.
..... Click the link for more information. (a French descendant of the water spaniel), the border collieborder collie,
breed of medium-sized, sheepherding dog developed in the British Isles. It stands about 18 in. (45.7 cm) high at the shoulder and weighs from 30 to 45 lb (13.6–20.4 kg).
..... Click the link for more information. (an English shepherd dog), the cavalier King Charles spanielcavalier King Charles spaniel,
breed of small dog developed in the early 20th cent. from the English toy spaniel. It stands about 12 in. (30 cm) high at the shoulder and weighs from 13 to 18 lb (6–8 kg).
..... Click the link for more information. , the Ibizan houndIbizan hound
, also called Ibizan Podenco, breed of tall, swift dog of ancient origin now found chiefly in the Balearic Islands and other areas of Spain. It stands from 22 to 28 in. (55.8–71.1 cm) high at the shoulder and weighs from 42 to 50 lb (19.1–22.7 kg).
..... Click the link for more information. (of Spanish origin), the miniature bull terrierminiature bull terrier,
breed of small, muscular dog developed in England in the early 19th cent. It stands up to 14 in. (35.6 cm) high at the shoulder and weighs about 17 lb (7.7 kg). Its short, flat, harsh coat is glossy white or white with brindle patches.
..... Click the link for more information. , the soft-coated wheaten terriersoft-coated wheaten terrier,
breed of medium-sized dog developed and perfected in Ireland. It stands from 17 to 19 in. (43.1–48.3 cm) high at the shoulder and weighs from 30 to 45 lb (13.6–20.4 kg).
..... Click the link for more information. (from Ireland), the Spinone ItalianoSpinone Italiano
, also called Italian pointer, breed of large, all-purpose hunting dog developed in the Piedmont district of NW Italy over three centuries ago. It stands from 20 to 26 in. (50.8–66.0 cm) high at the shoulder and weighs about 56 lb (25 kg).
..... Click the link for more information. , and the Tibetan terrierTibetan terrier,
breed of medium-sized dog originating in Tibet probably several thousand years ago. It stands from 14 to 16 in. (35.6–40.6 cm) high at the shoulder and weighs from 15 to 30 lb (6.8–13.6 kg).
..... Click the link for more information. .
Dogs registered by the AKC and other registry associations compete regularly in dog shows and field trials. In dog shows, the various breeds are judged solely on appearance, while in field trials they are rated according to their hunting skills.
See articles on individual dog breeds.
Female dogs, or bitches, will mate only when in heat, or estrus, which occurs about every six months and lasts from 18 to 22 days. Whelping (giving birth) occurs after a gestation period of about nine weeks. The size of the litter varies to some extent with the size of the dog: toy dogs rarely bear more than 2 puppies, while the largest breeds average closer to 10.
See E. Schneider-Leyer, Dogs of the World (1960); American Kennel Club, The Complete Dog Book (1968); E. H. Hart, Encyclopedia of Dog Breeds (1968); H. P. Davis, ed., The New Dog Encyclopedia (rev. ed. 1973).
Dog(religion, spiritualism, and occult)
The Dog is one of the 12 animals of the Chinese zodiac. It refers to one of the 12 earthly branches that are used in Chinese astrology, together with the 10 heavenly stems. Such a branch designates one day every 12 days: the days are named according to a sexagesimal (60) cycle, made of 10 series of 12 branches.
The Dog is not a jolly fellow. Introverted and ill at ease, he seems to have self-control and to be respectable, but this is a false front. He is shy and loving, and tends to devote himself to noble causes. Modest and without ambition, but courageous and a perfectionist, he does very well with social issues, but not in business. He has a tendency to be pessimistic.
(Canis lupus familiaris), a mammal of the family Canidae. Dogs are widely distributed throughout the world. Descended from the wolf, they were apparently domesticated during the Me-solithic period (Middle Stone Age; 13th to seventh millennia B.C.). In the process of domestication and breeding, more than 400 breeds of dogs have been developed, differing in size, body structure, hair covering, coloring, and behavior.
Anatomically, dogs are typical carnivores. They have 42 teeth—12 incisors, four canines, and 26 molars—of which the canines, or fangs, are the most developed. The dog is a digitigrade animal. Each front foot has five toes, one of which is a dewclaw. Each hind foot has four toes, although some breeds also have a dewclaw on each hind foot. The stomach is simple. The intestine is short, as in all carnivores. The brain is developed, which makes it possible to train dogs to perform the most diverse tasks. Dogs have keen hearing, good vision, and a highly developed sense of smell. They run, jump, and swim well. Females attain sexual maturity at seven to eight months, and males at ten to 12 months. The female is in estrus (comes into heat) once or twice a year, and the estrous cycle lasts about 20 days. It is advisable to breed the dog between the ninth and 12th day of the estrous cycle.
The gestation period is 58 to 65 days. A litter may contain only one or two pups or as many as 12 to 18 pups, which are born blind, deaf, and without teeth. The auditory canal usually opens between the fifth and eighth day, and the eyes open between the tenth and 14th day. The milk teeth appear between the 20th and 30th day. The nursing period is one to IV2 months. The life expectancy is generally ten to 12 years, although some dogs have been known to live to 16 or 17 years of age. The diet consists primarily of meat, cereals, bread, and vegetables; whole or ground bones, cod-liver oil, and bone meal are given as food supplements.
Depending on their use, dogs are housed in a variety of ways. Purebreds and watchdogs are generally housed in runs containing a wooden doghouse with an overhang. Sheep dogs are generally housed in tents in the summer, so that they are close to the flocks, and in doghouses in the winter. Dogs kept as pets generally sleep in the owner’s house.
Dogs are raised at special kennels, on hunting farms, at working-dog breeding clubs, and by hunting societies; many breeds are also raised by amateur dog breeders.
Modern breeds of dogs are divided into three groups: hunting dogs, working dogs, and house pets. The universally most popular house pet breeds are the small terriers (toy fox, Skye, Sealy-ham, Cairn, border, Kerry blue, Bedlington, and Yorkshire terriers), the miniature pinscher, the schnauzer, the poodle, the French bulldog, the chihuahua, the Japanese spaniel (chin), the Pekingese, the Maltese, and various spitz breeds.
Dogs may suffer from many infectious diseases that can be transmitted to man, including rabies, mange, ringworm, favus, and various helminthic diseases; for this reason, they must periodically be examined by a veterinarian.
REFERENCESMazover, A. P. Ekster’er i porody sluzhebnykh sobak. Moscow, 1947.
Pupyshev, P. F. Okhotnich’ilegavyesobaki. Moscow, 1949.
Sakharov, N. A. Tekhnika dressirovki sluzhebnykh sobak, 2nd ed. Moscow, 1963.
Posobie po sobakovodstvu, 2nd ed. Leningrad, 1973.
A. P. MAZOVER
What does it mean when you dream about a dog?
Dogs participate in the larger meaning of beasts or creatures, all of which can refer to our natural selves, in either the positive or negative sense of “animal.” Dogs, however, as some of the first domesticated animals, can refer to a wide variety of symbolic meanings, from going along with the “pack,” to hunting (dogs “sniff out” the quarry), to loyalty (“man’s best friend”), to abuse (“treated like a dog”), to exhaustion (“dog-tired”), to tenacity (“doggedness”). Also, as animals who guard the underworld, they can be messengers of the unconscious. As with all dream symbols, the tone and setting of the dream indicate which meaning is appropriate.