Mastiffs are considered the most massive breed recognized by many kennel clubs. There are two types of purebred mastiffs: the Old English Mastiff (also known as Mastiff and English Mastiff) and the Neapolitan Mastiff. They are easily distinguishable, given the proper information.
The most recognizable difference between the Old English Mastiff (OEM) and the Neapolitan Mastiff is their skin. According to the American Kennel Club, a Neapolitan is known for numerous folds and wrinkles around its face and neck, pendulous lips, and an ample dewlap. While OEMs have looser skin than other breeds, this abundant folding is absent.
The American Kennel Club lists Neapolitans' proper coloring as gray (blue), mahogany, tawny or black, with some brindling or white marks allowed. Old English Mastiffs are apricot, fawn-colored or brindled.
Both Mastiff breeds are massive, heavy-boned creatures. However, the Old English variety is considered slightly larger, with males a minimum of 30 inches and females a minimum of 27 1/2 inches at the shoulder. Neapolitan males are 26 to 31 inches at the shoulder, while females are 24 to 29 inches.
Neapolitan males average 150 pounds, while females usually weigh around 110 pounds. According to the National Kennel Club, Old English Mastiff males average 175 to 190 pounds. Both, however, are known to get considerably larger.
Neapolitan Mastiffs are famous for their rolling, lumbering gait. They push off hard from their hindquarters and extend their forelegs, producing this effect. The Old English gait is a bit more elegant--albeit still a bit lumbering--with forelegs tracking smoothly.
Both Mastiff varieties are considered ancient breeds, with records tracing back at least 2,000 years. They were well-documented in ancient Egypt, Persia, Mesopotamia, Asia and Rome, serving as war dogs and guardians. Despite this history, they are considered "gentle giants," especially the Old English variety. Loyal, gentle, noble and protective without being unnecessarily aggressive, a well-trained and exercised OEM can be an excellent pet.