The Giant Maso Mastiff is a relatively new and as yet, developing breed. The breed was just started in 2001 and will take several more years to complete before it can be officially classified as a dog breed. Developed from a mix of Old English Mastiff and Corso Italiano, the breed is being created to produce a healthier mastiff with a longer life expectancy. The Giant Maso Mastiff looks very much like the Old English Mastiff with a breeding height of 27 inches for females and 30 inches for males. Weight is at 175 to 200 pounds for males and 130 to 150 pounds for females. A wide variety of colours is allowed such as fawn, gray, gray brindle, reverse brindle, apricot and solid black. It also a shinier coat than that of the Old English Mastiff.
The breed is basically combining the desirable features and characteristics of its progenitors: the lovable and gentle temperament of the Old English Mastiff with the sharp intelligence and protective instincts of the Cane Corso. Breeders and owners of the Giant Maso Mastiff swear by its kind and dignified nature, calm and steady at home but still ever watchful and protective of its family. It craves human companionship and loves to please its owners. The Maso is fairly easy to train and are excellent with children. As it is still a developing breed, there is no known serious health problem for the Giant Maso but a regular exercise regimen always helps.