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Bullmastiff, photo 1

Origin

United Kingdom

Lifespan

7–9 years

Weight

41–59 kg

Height

61–69 cm

Personality

LoyalBraveReliableDocile

Colors & Patterns

Fawn · Red · Brindle

Bullmastiff

About This Breed

The Bullmastiff was developed in 19th-century England by crossing Bulldogs with Mastiffs to catch poachers on estates. Known as the 'Gamekeeper's Night Dog,' they are powerful yet gentle family guardians.

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Characteristics

Scores describe general breed tendencies, not an individual animal. A higher score means more of the named trait or need; it does not always mean better.

Family Affection
4/5
Good with Children
3/5
Good with Other Dogs
2/5
Shedding Level
3/5
Grooming Needs
2/5
Drooling Level
4/5
Friendly to Strangers
2/5
Playfulness
3/5
Watchdog Drive
5/5
Adaptability
3/5
Easy to Train
3/5
Energy Level
3/5
Barking frequency
2/5
Need for mental activity
3/5

Life with a Bullmastiff

Origin

OriginUnited Kingdom
GroupWorking

For the breed’s history, see the reference sources and Wikipedia link below.

Size and coat

Weight41–59 kg
Lifespan7–9 years
Height61–69 cm
Colors & PatternsFawn · Red · Brindle

These are approximate adult ranges. Individual animals may be smaller or larger.

Temperament

PersonalityLoyal · Brave · Reliable · Docile

Often enjoys a mix of activity and rest.

Often seeks company and attention. Allow time together and help it get used to short periods alone.

Coat care

Usually needs relatively little coat care. Brush as needed for its coat and shedding.

Some shedding is expected, and it may change with the season.

Living together

A familiar routine can help it settle in.

Teach children to handle it gently and leave it alone when it rests.

Introductions to other pets may take time. Provide separate spaces.

Training and activities

Practice in short sessions and reward the behavior you want.

Choose walks, sniffing games, and play to suit the dog’s age and health. Allow rest as well.

A lifespan range is not a prediction for an individual animal. Breed scores cannot diagnose illness or replace a veterinary assessment.

More from breed and care sources

Excerpts from the linked sources. Read the original for full details.

Breed Overview

The Bullmastiff is a loyal, affectionate, and giant dog breed. According to the American Bullmastiff Association, British gamekeepers created Bullmastiff dogs by crossing Bulldogs with Mastiffs in 1860. Their goal was to create an extra-large dog who would listen well to cues and act as a guardian against poachers. The Bullmastiff size is impressive—these dogs weigh 100–130 pounds and have a shoulder height of 24–27 inches, depending on their gender. They’re known for their large, broad head; V-shaped ears; dark eyes; and muscular build.

Care Guide

Bullmastiffs are docile and affectionate with family members, but they might take time to warm up to new people. They are good with young children and other dogs, though all interactions between kids and pets (no matter the breed) should be supervised. Bullmastiffs are extremely intelligent dogs and usually learn quickly during training. However, it’s important for pet parents to train and socialize this breed early—Bullmastiff puppies have lots of energy and grow to become very strong, giant dogs that can easily knock people and children over if they lack training. A Bullmastiff puppy needs to be trained to: Bullmastiffs need daily exercise, including long walks and playing within a fenced-in yard. But they don’t make good running companions because they don’t have the stamina to run long distances.