Bullmastiffs were bred by mixing Bulldogs and Mastiffs in England. They were bred to patrol country estates and protect it against poachers. These large dogs with their short muzzles could run quickly enough to catch a poacher and pin him to the ground until a gamekeeper could intervene. They later became popular additions to English dog shows.

Bullmastiffs were bred by mixing Bulldogs and Mastiffs.
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History and Origins
The Bullmastiff, which was known as the “Gamekeeper’s Night Dog,” had a significant role in the English aristocracy during the mid-to-late 19th century. Poachers were drawn to the large country estates and game preserves, and many of them risked facing the death penalty if they were caught in the act. To protect against this, gamekeepers were given Bullmastiffs to help guard against poachers. If a poacher was confronted by a gamekeeper, they might opt to fight instead of risking execution.
In order to protect their grounds, gamekeepers began to breed dogs that were powerful, fast, and courageous enough to apprehend an intruder in the darkness. After perfecting the ideal mix of Mastiffs and Bulldogs (60% Mastiff, 40% Bulldog), they created a canine that was intelligent enough to obey orders, gentle enough to detain without hurting, and formidable enough to intimidate any trespassers.
As the popularity of dog shows in England grew, people who had a fondness for Bullmastiffs began to compete and show off the best specimens they had. This eventually led to the Bullmastiff being officially registered with the Kennel Club in 1924. In 1933, the American Kennel Club (AKC) accepted the breed and granted it full recognition.

Bullmastiffs were originally bred to protect the animals in large game preserves from poachers.
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Size and Weight
Bullmastiffs are a large breed of dog. Males weigh between 110 and 130 pounds and are between 25 and 27 inches tall. Females are slightly smaller, weighing between 100 and 120 pounds, and standing between 24 and 26 inches tall. When they are three months old, Bullmastiff puppies generally weigh between 34 and 43 pounds. A Bullmastiff will be fully grown by the time they are 19 months old.
Common Health Issues
Overall, this is a healthy breed of dog; however, it is prone to a few common health issues. All owners should be aware of these issues and contact their vet if they are concerned.
Since Bullmastiffs have short muzzles, they are more prone to suffering from heatstroke or heat exhaustion. It is important to keep this breed indoors during particularly hot days. During warmer months, try to exercise your Bullmastiff earlier in the morning or in the evening when it is cooler outside.
Hip dysplasia is another health concern that some Bullmastiffs may face, where the thighbone doesn’t fit correctly into the hip bone. The two bones will rub together, causing pain and possibly limping over time. The condition is passed down through the parents, so it is important to find out the history of a dog’s parents from a breeder.
Some Bullmastiffs may also develop hypothyroidism. This condition is caused when there is a deficiency in the dog’s thyroid hormone. It can lead to other problems, such as obesity, lethargy, and infertility. Dogs with hypothyroidism will need to be medicated for the rest of their life.
Temperament and Behavior
This breed has a calm temperament. So, they can be very gentle and loving when they are with their family members whom they know and trust. These traits make them a good pick for families with older children who are on the calmer side.
However, when a Bullmastiff encounters a stranger, their behavior can change to be more suspicious or aggressive. They are independent dogs who are not always easy to train. They do best with experienced owners who know how to be both loving and firm.
How to Take Care of a Bullmastiff
When planning to take care of a Bullmastiff, you should think about this breed’s temperament, nutritional needs, common health concerns, and other unique traits.
The Best Dog Food
Finding healthy and nutritious food that will meet your dog’s needs is important. Therefore, look for large-breed dog food options from reputable companies. Organic dog food is a popular option for owners of breeds like this that can have endocrine/hormonal disorders like hypothyroidism. If you are unsure if a certain food is right for your dog, your veterinarian is always a good resource.
As large-sized dogs, Bullmastiffs eat a lot of food. In fact, most will eat between 3 1/8 and 4 1/8 cups of food each day. However, the exact amount of food your dog will need will depend on his weight, activity level, health concerns, age, and other factors. Splitting the total amount of food that your dog needs into two portions is important in preventing bloat, which can be caused when dogs eat too much at one time. Additionally, you should avoid giving your Bullmastiff vigorous exercise right before or right after they eat because this can also be a cause of bloat.
Puppies should also eat large-breed puppy food because this will help them to grow at a steady rate. They should be fed multiple times throughout the day to accommodate their smaller stomachs. As the puppies get older, the number of times they eat each day can be reduced.
Maintenance and Grooming
During their shedding season, this breed will shed some. However, keeping your dog well-groomed and brushing them can keep the shedding at bay. Be sure to monitor your dog’s skin. If you notice that it is too dry to too oily, it could be an indication that their nutritional needs are not being met or that they have developed an allergy to something.
Training
Because this breed is stubborn, it can be a challenge to train. Many times, these dogs will do best when they are enrolled in an obedience class from a very early age. Making sure your dog is properly trained and socialized from an early age is very important for keeping this breed under control. Early training can also help a Bullmastiff develop a stronger bond with its owner.

Bullmastiffs were bred to be persistent in tough situations. This can translate to stubbornness during training, so patience is required.
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Exercise
Even though some dogs will seem content just lying around or hanging out in the house all day, it is important to make sure this breed gets exercise every day. Taking your dog for a walk and playing with them in a fenced-in backyard are great ways to get them the activity they need.
Puppies
First of all, if you are bringing home a Bullmastiff puppy, you will want to make sure your house is ready for the dog. Puppy-proof your home by removing anything potentially hazardous or that you wouldn’t want to get destroyed by a dog chewing on it.
It will be very important to begin training your dog as soon as you bring them home. Bullmastiffs will be much easier to manage when they are smaller, and the earlier they start the training process, the easier it will be. With this in mind, make sure to find opportunities to socialize your dog as well. This will help them learn how to act around other people and dogs.
Crate training your Bullmastiff can help with potty training. It can also help prevent the puppy from chewing up your things when you are away from the house.
Bullmastiff puppies will need some playtime and exercise. However, you will want to be careful not to overexercise a puppy since they go through a period of rapid growth. That’s because too much exercise can have a negative impact on the development of their bones and muscles.

It is best to start the socialization of puppies early.
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With Children
When raised alongside a child, a Bullmastiff can be a good family pet. They are very loyal to the members of their family and can be quite affectionate. It is important to note that Bullmastiffs are not trusting of other people, which could pose a problem when children bring friends home.
Bullmastiff Pictures
View all of our Bullmastiff pictures in the gallery.
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Sources
- American Kennel Club / Accessed November 8, 2019
- Dog Time / Accessed November 8, 2019
- Wikipedia / Accessed November 8, 2019
- Hill's / Accessed November 8, 2019
- Pet Finder / Accessed November 8, 2019
- Adopt-a-Pet / Accessed November 8, 2019
- Dogell / Accessed November 8, 2019
- Dogell / Accessed November 8, 2019
- Dogell / Accessed November 8, 2019