Are Bullmastiff Dogs
Aggressive or Dangerous?
Find Out Before Bringing One Home

Owning a dog is an excellent option for many people, but you have to be careful. Not all dogs make great pets for all people and families. Whether you’re new to dogs or have a big family, you should consider a few breeds to choose the best dog for you.

Bullmastiffs can be dangerous if they don’t have proper training and socialization from their owners. These dogs are guard dogs, so they can be very territorial, and that can make them aggressive. But they can also be sweet and gentle. Training and socializing a Bullmastiff early can emphasize those calmer traits.

If you’re interested in owning a Bullmastiff, you should consider their temperament. You should also consider your lifestyle and if you’re able to handle training such a dog breed. Read on to learn more about Bullmastiffs. Read More Below...

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Large Bullmastiff in a car


Bullmastiff Overview

A Bullmastiff is more popular than many breeds, but it’s not the most popular. These dogs are part of the working group for the American Kennel Club, and they have a short life expectancy of seven to nine years. 

They’re great guard dogs, and they have helped protect game from poachers. Bullmastiffs are related to Mastiffs, but they’re not as big. Still, a Bullmastiff can grow to be very large as an adult.

Nowadays, these dogs can act as guard dogs for your house, and they make good family pets. But you do have to consider their size and personality before you bring one home to your family.

Size and Body

Adult Bullmastiffs weigh about 100 to 130 pounds, and males are heavier than females. Males grow to be 25 to 27 inches tall, and females can be 24 to 26 inches tall.

They have a lot of muscle, so that makes Bullmastiffs very powerful. As puppies, they grow quickly, and they get even stronger as they grow. So even if you get one as a puppy, know that they won’t be that small for long.

While they don’t need as much physical activity as some large dogs, they do need it when they’re growing. They can also take up a lot of space, so you need room for your dog where you live.


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How Aggressive Or Dangerous Is A Bullmastiff?

When trained well, Bullmastiffs can be loving and kind to people and other pets. At their core, Bullmastiffs are very loyal and protective. That made them good hunting companions and family pets, but not all Bullmastiffs are as kind.

If a dog doesn’t receive training, they can be aggressive and dangerous. Their large size is enough to pose a danger to some children and small animals. If you want to ensure your Bullmastiff is calm and sweet, you’ll need to train them well and consistently.

Bullmastiffs can be great around kids and other pets. But they are guard dogs, so it might be hard to bring a new pet into the house after you’ve had your Bullmastiff. Consider all of these things when deciding if this breed is right for you.

Does Your Bullmastiff Have To Be Dangerous?

When determining if Bullmastiffs are dangerous or aggressive, there’s no easy answer. Some Bullmastiffs can be dangerous. But others can be kind and loving, and some people call the breed a gentle giant.

The difference between an aggressive and a non-aggressive Bullmastiff has a lot to do with training. Their environment can also make a difference, but those two things go hand in hand. Odds are a dog that receives little, or no training probably doesn’t live in the best place.

But good owners typically want to train their Bullmastiff. That way, the dog can live comfortably with the family.

Keep these things in mind when training a Bullmastiff not to be aggressive or dangerous.

Bullmastiff Socialization

The earlier you can give your Bullmastiff some socialization, the better. These dogs grow and reach their adult size very fast, so it can be harder to control the dog later on. You should start working with your Bullmastiff when they’re small, and you can control the dog.

Take your dog to a dog park or to meet other friends with dogs. That way, your dog can get to know other people and dogs and not think of them as a threat.

You’ll be able to hold your dog on a leash, so you can intervene if your dog starts to act out. If you wait too long before introducing them to other people, they may get territorial or aggressive.

Starting to socialize your dog when they’re young will also help them catch on quicker. If you don’t give your Bullmastiff a chance to act out, it will learn that it should behave and be calm. As you do this, you can use treats and other tools, but make sure you start as soon as you can.

General Training Classes

While you can and should start socializing your Bullmastiff at home, it can also help to take your dog to training classes. You can find classes at a local pet store, through a vet, or at a community center.

General training classes can teach you and your dog a bit. You can learn what tricks to use to train your dog and get their attention. Your dog can learn how to act in public and how to interact with other dogs.

That’s especially important if you may want another dog later. When you do get another pet, your Bullmastiff will have experience with other dogs. So that can help your dog from getting too territorial.

You don’t have to go to a ton of training classes. Start with a short-term rotation of lessons over the course of a couple of months. That way, your dog can get out of the house, and they can meet other dogs and get that social time.

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What About Adopting An Adult Bullmastiff?

A lot of the things you can do to keep a Bullmastiff from being dangerous involve training. And in most cases, that training should start from a young age. However, that doesn’t mean you shouldn’t consider getting an adult Bullmastiff.

Before you get an adult, you should consider the dog’s past. Ask the shelter about how they found the dog. See if you can learn about the prior owner and if they did any training with the dog.

Bullmastiffs And Other Pets

Bullmastiffs can do well with other Bullmastiffs and other dog breeds and cats. But it all goes back to socialization. A natural guard dog, a Bullmastiff might not like when another dog comes into their territory.

You can help this by introducing the new pet outside of your home so that your Bullmastiff doesn’t have to protect their territory. And if you already have pets, you can do the same to introduce a Bullmastiff into your household.

Bullmastiffs With Kids

As long as your Bullmastiff is around kids when the dog is young, you can have kids and a Bullmastiff. You should start by having your dog meet your kids in short bursts. Make sure you or another adult is there to supervise in case the dog acts up.

You can also talk to your kids about how to behave around the dog. Tell your kids not to get aggressive with the dog. Instead, have your kids start by petting the Bullmastiff. As your kids and Bullmastiff get to know each other, they can form a close bond which also makes this breed a good family dog.

Will A Bullmastiff Attack An Intruder?

Another thing to consider is if a Bullmastiff will attack intruders in your home. They are guard dogs, so they will get aggressive if they need to. You can trust that your dog will protect you, even if you train them to usually be gentle.

But make sure you train your dog to be calm around common visitors. That way, you don’t have to worry about your dog attacking a friend or relative.

Final Thoughts

Bullmastiffs can be aggressive and dangerous, but they can also be sweet and gentle. Luckily, you can train your dog to be sweeter, and they can be a great family pet. But don’t forget to keep training your dog and reminding them to behave well.

These Pages Of Ours Will Tell You More About The Bullmastiffs Temperament


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