North American Mastiff – Amazing Facts

The North American Mastiff also goes by the name AM Mastiff. It is a pure dog breed that descends from the English Mastiff, a large fearsome dog with many tales about it.

The difference between the English version and this dog is the face. North American Mastiff has a “drier mouth”. This means it drools less, probably due to a smaller overhanging lip area.

There are several amazing facts below that may make you want to adopt an American Mastiff.

It descends from the English Mastiff

Despite the name North American Mastiff, it is actually bred from the English Mastiff. This may come as a surprise for many but the Mastiffs are European or Asian dog breeds that only came to the USA with English settlers.

In the 1990s serious attempts were made to keep this breed alive in the USA. Through these efforts, the North American Mastiff became a stable dog breed.

It bears many resembling features of the Mastiff breed. There are only a few certified breeders who take care of breeding this specific dog.

American Mastiff Defining Features

Inheriting the Mastiff size, the American Mastiff is a huge dog. Some distinguishing features are a rectangular head, high floppy ears, slightly less overhanging lips, a few wrinkles, and a black nose.

People say they have a less intimidating facial expression than other Mastiff breeds! 

The body is well built all around with muscle, making them look athletic and intimidating. Their back is long and straight packed with strong limbs. Each limb is equipped with a large paw that is heavily padded.

They have a long whip-like tail ending this well-built agile dog.

North American Mastiff

The American Mastiff is a Giant!

There is no denying that a giant dog like the American Mastiff comes coupled with immense weight! Males definitely outsize and outweigh their female counterparts. Their body is built of sheer muscle and heavy-bones! 

Male American Mastiff dogs weigh 160 to 200 pounds! They can reach a height of up to 28 to 36 inches. Shocking isn’t it?

Female American Mastiff dogs weigh 140 to 180 pounds. Their height lies between 26 and 34 inches, relatively less than the males. 

Given their large size, they obviously require a large yard or farm! It should take time and thought to decide if you would want such a big dog.

Interesting Read – Amazing facts about Dogo Argentino

Are American Mastiffs Long-Lived?

How long do North American Mastiff dogs live for? They have an average lifespan of 10 to 12 years. So they are not a very long-living dog breed like other large dogs.

Providing your dog with quality dog food, healthcare visits, and a safe environment can help him live longer and have a better quality of life.

Do They Live up to Their Mastiff Title?

The Mastiff is an ancient dog breed type that still exists today. They have always been used for guarding, defending, or protecting humans or animals.

The North American Mastiff also acts as a defender and protector of his family and makes for a loyal partner. 

But in addition, this dog has adapted to become a great companion for families with children and other animals. He makes all this possible without the need to be aggressive or overly physical about it.

How Likely are you to get Bitten?

Most Mastiffs are a breed that are accompanied by complaints of biting and ferocity. Just because the American Mastiff is a Mastiff breed doesn’t mean they are vicious. It is actually the opposite. 

American Mastiffs are highly loyal, courageous, and affectionate canines. They are not at all ill-tempered or vicious like other Mastiff variants. This cool and calm temperament could be due to the crossing with possibly the Anatolian dog.

They do not show any signs of danger to humans or even animals that are smaller. This is why you can see this dog in homes with kids and even cats!

They Show Many Coat Colors and Patterns

The North American Mastiff wears a short coat that looks attractive regardless of color. There are many colors and patterns that are common in them.

Coat colors include:

  • Fawn
  • Apricot
  • Tan
  • Brown
  • Black

Patterns you are likely to find include:

  • Pied
  • Merle
  • Brindle

In addition to these colors and patterns, this dog can feature a black mask on his face. This black mask gives the dog a unique appearance when it does occur. White markings on the chest can be common.

Watch out for these Health Issues

Each dog comes with a set of diseases that it may be prone to. Health risks of the American Mastiff usually include :

  1. Joint Dysplasia
  2. Bloat
  3. Eye Problems

Apart from these high risk illnesses, you should also look out for these uncommon health issues:

  1. Skin Problems
  2. Hyperthyroidism

A variety of illnesses that may be overlooked by us can be picked up by a trained vet. This is why these dreaded visits are important. 

Pro’s vs Con’s

With any dog breed, there are positive features and negative features. Here is a sum up to help you make your decision to adopt a North American Mastiff: 


  • Makes a great guard and companion
  • Limited grooming efforts required
  • Not very vicious or dangerous
  • Safe around other pets (even cats)


  • Very large and heavy dog
  • Difficult to train
  • Stubborn and independent 
  • Requires an experienced owner only!

How much does an American Mastiff Puppy Cost?

These heavy-boned dogs are likely to cost between $1000 to $1500. This price could go up depending on certification, coat color, or genetics. 

Grooming Efforts are Minimal

Having a short coat that rarely gets dirty does have many advantages. The coat only requires a weekly brush, maybe more if he will let you. It is known that short hair coats are less likely to get tangled or have items lodged in them.

A once in four to six weeks bath is all that is required to keep him clean enough to thrive. 

Strengths and Weaknesses

Overall, the Strength of the American Mastiff is his temperament. His simmered-down temperament qualifies him as both a working breed and a companion breed.

His biggest weakness may be his size and certain health conditions that contribute to decreased life expectancy. Joint issues could lead to decreased mobility and a hefty vet bill!

The American Mastiff is Linked to an Ancient Dog Breed

There are many references to the Mastiff being related to the Alaunt and Molosser dogs. Evidence points out that these dogs existed in 2500 to 4500 B.C in the Asian mountains.

The British Museum even has ancient Babylonian relics that depict Mastiff-like dogs that would hunt lions. The Romans came across these animals in Britain and took them back to Rome to fight in arenas.

The Mastiff breeds as we see today may be linked to these ancient dogs and bear high resemblance in both features and agility. 

Beware of Flatulence and Snoring!

Proud American Mastiff owners do complain of some rather embarrassing characteristics of the American Mastiff. They are prone to flatulence and there is very little you can do besides changing their diet.

Also, while they are catching a nap prepare yourself for snoring. Expect loud snoring with the chances of a small pool of drool, they are Mastiffs after all!

Who are the Parents?

The American Mastiff is the dog created by breeding an English Mastiff and an Anatolian Shepherd dog. Both dogs are large and the American Mastiff is no exception. 

The Anatolian Shepherd dog originates from ancient dog breeds. It is a working dog that was used to protect livestock or families. They are not dangerous and fit as a companion dog that is suitable for kids, cats, and other dogs! 

The English Mastiff is referred to as the “Old English Mastiff’ since it was the original species found in Britain. These ancestors were very good at guarding and hunting.

The ones we see today are very less dangerous and more suitable as companions. Training and socializing are still needed to avoid any accidents!

Together, the traits of both parents create a dog that is a caring companion who will defend his family till death. 

On a Scale of 1 to 10, how Tough is Training?

Undoubtedly, training this giant dog is going to be difficult. Probably a 7 or 8 in difficulty.

This high difficulty in training is not just due to his stubbornness and independent nature. This Mastiff is also sensitive! Using harsh words or making him feel very nervous can affect him.

It causes him to become unresponsive, bored, or tired. All these feelings result in a low rate of success in training him. This is why socializing can help the process by eliminating nerves and fear from the dog while in puppyhood.

Important American Mastiff Care Tips

Being a large dog, an owner must not forget these care tips:


Brushing teeth is a good habit as it can dislodge food and meat which become wedged in between teeth. The spaces between teeth are large and can hold more pieces of food. This can lead to decaying matter that affects teeth and breath. 

Ear Checks

Ears should be cleaned or at least checked. Try to keep the ear canal dry and clean to avoid pests and infections. If you cannot do this, have a vet do it for you.

Nail Clipping 

Trimming of nails must be a monthly routine. Long nails become uncomfortable for the dog. The nails can also lead to the destruction of furniture! 

Facial Folds

Most Mastiffs have wrinkles on their face. This trademark feature can cause a few problems. This is where hygiene and care are vital. Sweat accumulates under these wrinkles which can cause skin infections. 

The skin beneath the folds need to be cleaned and dried off properly to avoid becoming infected.