There is no difference between a bullmastiff and an American bullmastiff. In fact, there is only the breed called bullmastiff, and not a separate breed called American bullmastiff. The bullmastiff, which originated in England, has been a recognized breed of the American Kennel Club since 1933. There is an American Bullmastiff Association for owners and supporters of the breed.
The bullmastiff is the result of breeding experiments in England that mated bulldogs with mastiffs. The breed was created with the specific purpose of guarding the game that lived on expansive estates from poachers, which were a common nuisance for large country properties. The bullmastiff served its intended purpose because of its speed, its keen tracking abilities and its power, which enabled it to corner and contain poachers when they were caught.
The bullmastiff is a strikingly large and powerful dog. Males can weigh up to 130 pounds, and females can reach 120 pounds. A bullmastiff's head is a particularly large and prominent feature. The bullmastiff often shows an engaged expression on its black-masked face and has kind-looking eyes. The breed has short hair, and it tends to come in coats of fawn, red or brindle, according to the American Bullmastiff Association.
Despite its intimidating size, the bullmastiff has a reputation as a breed with a gentle, easygoing personality. It is family-friendly and tends to get along with children with the proper training. However, they do have problems sharing a home with other dogs. Bullmastiffs are known as strong-willed, stubborn dogs and take determined training by an owner. And, because of the combination of its stubbornness and size, training is particularly important to managing a bullmastiff as a pet. Bullmastiff's ancestry as property guardians means that they are natural guard dogs. Still, unlike other guard dog types, bullmastiffs do not bark frequently.
Bullmastiffs do not require excessive grooming or care, but simply need the type of care common for other breeds. Slobbering and snoring are common for the breed. Bullmastiffs struggle in particularly hot or cold weather. Cancer, hip and elbow dysplasia, bloating and lip boils are among the typical health complications that the bullmastiff faces. Daily exercise translates to the best possible behavior. The bullmastiff lives a maximum of about 10 years. It has an average litter size of eight puppies, according to the Dog Breed Info Center.