types:
police dog
any dog trained to assist police especially in tracking
boxer
a breed of stocky medium-sized short-haired dog with a brindled coat and square-jawed muzzle developed in Germany
mastiff
an old breed of powerful deep-chested smooth-coated dog used chiefly as a watchdog and guard dog
bull mastiff
large powerful breed developed by crossing the bulldog and the mastiff
English bulldog,
bulldog
a sturdy thickset short-haired breed with a large head and strong undershot lower jaw; developed originally in England for bull baiting
Great Dane
very large powerful smooth-coated breed of dog
hearing dog
dog trained to assist the deaf by signaling the occurrence of certain sounds
Saint Bernard,
St Bernard
a Swiss alpine breed of large powerful dog with a thick coat of hair used as a rescue dog
kuvasz
long-established Hungarian breed of tall light-footed but sturdy white dog; used also as a hunting dog
attack dog
a watchdog trained to attack on command
schipperke
breed of small stocky black dogs originally used as watchdogs on boats in the Netherlands and Belgium
briard
old French breed of large strong usually black dogs having a long tail and long wavy and slightly stiff coat
kelpie
an Australian sheepdog with pointed ears
komondor
Hungarian breed of large powerful shaggy-coated white dog; used also as guard dog
Old English sheepdog,
bobtail
large sheepdog with a profuse shaggy bluish-grey-and-white coat and short tail; believed to trace back to the Roman occupation of Britain
collie
a silky-coated sheepdog with a long ruff and long narrow head developed in Scotland
Border collie
developed in the area between Scotland and England usually having a black coat with white on the head and tip of tail used for herding both sheep and cattle
pinscher
any of three breeds of dogs whose ears and tail are usually cropped
Bernese mountain dog
large powerful long-haired black-coated Swiss dog with deep tan or russet markings on legs and white blaze and feet and chest marking; formerly used for draft
Tibetan mastiff
very large powerful rough-coated dog native to central Asia
French bulldog
small stocky version of the bulldog having a sleek coat and square head
Seeing Eye dog
(trademark) a guide dog trained to guide a blind person
Siberian husky
breed of sled dog developed in northeastern Siberia; they resemble the larger Alaskan malamutes