Toy dog term teacup dog, thus the toy/teacup boundary remains fuzzy. The standard size for a toy dog ranges from 4 to 7 pounds; anything smaller than the standard size of a toy dog may be a runt of a litter. No official size defines a teacup dog, but unofficially a teacup dog is considered to be a dog that is 17 inches or less and weighs 4 lbs or less at the age of 12 months. There are no specific teacup dog breeds, but popular types for breeding teacup dogs include: Shih Tzu, Chihuahua, Yorkshire Terrier, Poodle, Pug, Maltese, Pomeranian, and
Dog anatomy as the German Shepherd Dog, are called mesocephalic and dogs with a pushed in muzzle, such as the Pug, are called brachycephalic. Today's toy breeds have skeletons that mature in only a few months, while giant breeds, such as the Mastiffs, take 16 to 18 months for the skeleton to mature. Dwarfism has affected the proportions of some breeds' skeletons, as in the Basset Hound. All dogs (and all living Canidae) have a ligament connecting the spinous process of their first thoracic (or chest) vertebra to the back of the axis bone (second cervical or neck bone), which supports the