companion dog

Companion dog usually describes a dog that does not work, providing only companionship as a pet, rather than usefulness by doing specific tasks. Many of the toy dog breeds are used only for the pleasure of their company, not as workers. Any dog can be a companion dog, and many working types such as retrievers are enjoyed primarily for their friendly nature as a family pet, as are mixed breed dogs.
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Dogs in the companion group are intensely devoted to their human family and crave first and foremost their owner's attention; social isolation is the worst punishment they can endure. Most are diminutive, but a few are medium-size to large.
Certain early companion dogs were probably bred from species "dwarfs"--typically characterized by broad, rounded back skulls; thickened joints; long bodies; and squat legs. The Pekingese (one of the oldest breeds), Lhasa apso, Shih Tzu, Japanese Chin, and Tibetan spaniel retain such characteristics.
Some breeds, on the other hand, are miniaturizations of larger breeds , with no evidence of dwarfism. Examples include the French bulldog and the toy poodle.
Among the most ancient companion breeds, bichons--including the Maltese, bichon frise, Havanese, Bolognese, and Coton de Tulear-- brought to the Mediterranean region 2,000 years ago by the Phoenicians. They all have a silhouette that is longer than it is tall, a tail that curls over the back, and a sweet social temperament, traits inherited from their common ancestors.
Toy-size terriers are represented in the category by silky, Boston, and terriers; Brussels griffons; miniature pinschers; and affenpinschers. Most of these pint-size watchdogs are quick to sound an alarm and quite willing to challenge larger dogs over territory. They are also playful, active, humorous dogs--and a training challenge because of their self-possessed stubbornness.
Brains and beauty can be found in a more manageable package in the English toy spaniel, King Charles spaniel, and papillon. These easygoing, cooperative dogs excel in obedience and agility, especially the papillon. The country of origin for both the Chihuahua and Chinese crested may be in dispute, but their roles as bedwarmers and close confidants are not. Several larger breeds fall into the companion-dog category: the Tibetan terrier (once used for herding), the firehouse dalmatian, and the water-retrieving standard poodle. These household companions have higher energy levels and are much more demanding than their smaller group mates.
Companion Dogs:
Affenpinscher , Bichon Frise , Bolognese , Boston Terrier , Brussels Griffon , Cavalier King Charles Spaniel , Chihuahua , Chinese Crested , Companion Dog Mixes , Coton de Tulear , Dalmatian , English Toy Spaniel , French Bulldog , Havanese , Japanese Chin , Lhasa Apso , Maltese , Miniature Pinscher , Papillon , Pekingese , Poodle , Poodle Mixes , Pug , Shih Tzu , Silky Terrier , Tibetan Spaniel , Tibetan Terrier , Yorkshire Terrier .