Physical attributes

The Tibetan Mastiff is among the largest breeds. It is found in a heavier mastiff type and a more moderately sized mountain type. Its sturdy bone structure and large, wide head makes it appear considerably more massive than other dogs of a similar height. It can reach heights up to 31+ inches (80+cm) at the withers, although the standard for the breed is typically in the 25 to 28 inch (61 to 72 cm) range. History records the largest of the breed weighing over 110 kg but dogs in America are more typically between 100lb (45kg) to 160lb (72kg). The Tibetan Mastiff is considered a primitive breed and is one of the only dog breeds that have a single oestrus per year instead of two. This characteristic is still found in more primitive canids species like wolf. Since their oestrus usually takes place during late fall, most Tibetan Mastiff puppies are born between December and January.
Its double coat is long, and found in a wide variety of colors from solid black to tri-color with the rarest being white. Like other types of mastiffs, the larger variety has a heavier head and more pronounced wrinkling, while the mountain type has a smoother brow with less jowling, giving them a drier mouth than other mastiff breeds. They are also hypoallergenic with a thick double coat that only sheds once per year.
Tibetan Mastiffs are separated by Chinese breed-standard into two categories - Lion Head (relatively smaller in size, exceptionally long hair from forehead to withers, creating a ruff or mane) and Tiger Head ( larger in size, shorter hair)