Maybe a Mastiff? Here's a breed description that looks like this fella ...
The Mastiff, also known as the English Mastiff and Old English Mastiff, is one of the heaviest breeds — an adult male can weigh more than 200 pounds. He is massive, powerful, stately and noble in appearance and he is known as the gentle giant of the dog world.
The Mastiff is a versatile working dog. His great strength was once used to turn water wheels, pull carts and carry heavy loads on his back. He was also orginally used as a guardian and fighting dog. Today, Mastiffs are excellent companions and family members. They can be seen participating in various activities such as carting, tracking, weight pulling, obedience competition and conformation. They are also used as Therapy Dogs and in Search and Rescue.
The Mastiff is watchful, self-confident and patient. He is very devoted to his family and will protect both his family and property in a calm and dignified manner. While some Mastiffs tend to be aloof with strangers, others are fairly friendly. However, the breed has a strong guarding instinct and will always be very watchful of strangers entering the home and/or around his family members. His good nature, patience and calm, steady demeanor also means that he is generally excellent with children. The Mastiff needs human companionship and is not a dog to be left alone for long periods of time.
Physically, the Mastiff is massive, heavy boned, and muscular. He gives an overall impression of grandeur, power and dignity. Although the Mastiff grows at a tremendous rate for the first 12 months, he does not physically or mentally mature until the age of three or four years. His outer coat is moderately coarse and the under coat is dense, short and close lying. The coat colour is either apricot, silver fawn or dark fawn-brindle. The muzzle, nose and ears are always dark in colour, the darker the better.
A few notes about the breed:
— All Mastiffs slobber. The amount varies from one dog to the next. While some slobber only when eating, drinking or when they are hot; others seem to slobber constantly.
— Another characteristic of the breed is snoring. Snoring is genetic and caused by a long soft palate (this does not mean he has a long muzzle), so some Mastiffs snore occasionally and others snore very loudly and often.
— According to the MCOA, the Guinness Book of Records holder for the world's largest dog is a Mastiff named Zorba. In 1989, when he was 8 years old, Zorba weighed 343 pounds and measured 37 inches at the shoulder. From the tip of his nose to the tip of his tail, Zorba was 8 feet 3 inches in length.