Bred for protection work, the Bullmastiff is larger than most guard breeds, but should not be exaggerated or coarse to interfere with its fluid movement. Own. Malina Raby and Peter Kozel.

An adult Bullmastiff weighs between 50 and 60 kg; the female, between 41 and 50 kg; the male adult stands between 63 and 69 cm; the female, between 60 and 66 cm. Animal with a large and powerful build, although compact, the Bullmastiff has a large and wide head, with some wrinkles, sagacious expression, strong and wide and deep muzzle; moderate stop; flat skull. The neck is thick, almost with the same diameter than its head. The upper outline should be straight; the chest, wide and deep; the back short. The tail is high inserted and is straight or curved, but not carried “hound” style. The motor group displays free, driven movement; the shoulders unloaded, the hindquarters straight, the elbows not opened or tucked in; good angulations. The coat is short and thick, color red, fawn or brindle; a single white patch on the chest is allowed.
Bred as a guardian, the Bullmastiff with its pure muscle 60 kg will make any intruder change his mind. The Bullmastiff adores its family, and despite its size it loves to be inside the house, where it feels comfortable and relaxed. It grows fond of the entire family, and defends each member to death, including the home’s cat and pig. It is brave but tame, and a well bred specimen is lively and agile at the same time, enjoying exercise time with the family members. Most Bullmastiffs are dominant with strange dogs and not sociable towards people, if not introduced by a familiar person.
Even puppies have a protective air, suspicious towards strangers by nature. 
Weigh at birth is between 170 and 680 g and there doesn’t seem to be correlation between birth weight and adult size. After seven weeks, the puppy weighs between 6.5 and 7 kg, and at 16 weeks, between 22 and 25 kg. Too large specimens should be avoided, due to bone and joint problem risks. The breed is large on its own, so an excess is absurd. The future owner should take note of the puppy’s build: it should be solid, well done and balanced. Watch for short tails, curled tails and cleft palates. Character is also an important factor and a character checks in the breeder’s lines is important. The Bullmastiff puppy should be obliging and content in human company. Natural mistrust before strangers is typical and desirable. With proper training the Bullmastiff can become a fantastic guardian and protector. Diet will be another important issue: it is well known that the Bullmastiff has its individual demands, and the best is to consult the breeder or veterinarian to determine a nutritional program. Calcium supplements are often detrimental.
The puppy should be well built, move easily, obliging and not shy. 
Cancer and stomach torsion make more victims than any other anomaly affecting the breed. Although neither of them can be prevented, their incidence can be limited providing the dog with a healthy life, including a prescribed diet and routine exercise. Hip dysplasia is a large concern amongst breeders, and X – rays are essential. Skin and eye problems occur (including eczemas, dermatitis, muzzle pyoderma and alopecia, entropion, glaucoma and progressive retinal atrophy). Hereditary back malformation (cervical malformation) occurs on several degrees, producing from a mild limp to partial paralysis. Tumors and kidney stones usually affect older dogs. The Bullmastiff usually lives to ten years.
Make sure that the parents have certificates assuring that they are free from hip dysplasia, and ask about cancer incidence on the breeder’s lines.