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American Mastiff

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 American Mastiff

The American Mastiff is a giant size recent breed that has been developed crossing the Anatolian Mastiff (Anatolian Shepherd Dog) with the English Mastiff, with specific intentions of having a Mastiff breed that had a better lifespan, less problems with hip dysplasia and less drooling. It comes from the US and makes a great companion and family dog, size does not equate to aggressive, in fact this dog is calm, tender, social and well mannered. Its life span is 8 to 12 years and its size means it is best with owners able to lead who have some experience. There is some controversy over this breed with English Mastiff breeders who mostly are against its breeding. It should also be noted that the American Mastiff is not the same as the Panja American Mastiff.

The American Mastiff at A Glance
Name American Mastiff
Other names AM Mastiff
Nicknames AM
Origin US
Average size Giant
Average weight 120 to 200 pounds
Average height 28 to 36 inches
Life span 8 to 12 years
Coat type Short and dense
Hypoallergenic No
Color Fawn, apricot and brindle with white markings acceptable on feet, chest and chin/nose
Popularity Not a registered member of the AKC
Intelligence Above average
Tolerance to heat Low to moderate – needs to be monitored in the heat
Tolerance to cold Good – but nothing extreme
Shedding Average to heavy
Drooling Average to above average – there is some debate on whether they drool less than the English Mastiff
Obesity Average – make sure it is not over fed and it is well exercised and it should not be a problem
Grooming/brushing Average – brush twice a week or more if shedding is especially heavy
Barking Rare – does not bark much but its bark is deep and loud when it does
Exercise needs Moderate – its size means it needs a certain level of physical exercise but it can adapt to owners' activity levels
Trainability Moderately hard
Friendliness Good to very good
Good first dog Low – giant dogs need experienced owners
Good family pet Very good with socialization
Good with children Very good with socialization
Good with other dogs Good if socialized
Good with other pets Good with socialization and if raised together
Good with strangers Good with socialization but protective of his owner and family
Good apartment dog Moderate – it is not active indoors so can adapt but best in a home with space and a yard
Handles alone time well Low – can become destructive or depressed if left alone too long
Health issues Much debated - see section below
Medical expenses $485 a year for pet insurance and basic health care
Food expenses $570 a year for high quality dry dog food and dog treats
Miscellaneous expenses $245 a year for license, miscellaneous items, basic training and toys
Average annual expenses $1300 as a starting figure
Cost to purchase $1,550
Rescue organizations American Mastiff Rescue, Mastiff to Mutts rescue, Mastiff Rescue Oregon
Biting Statistics None specific to American Mastiff, but under heading of Mastiffs there have been Attacks doing bodily harm: 28, Child victims: 23, Deaths: 5, Maimings: 17

The American Mastiff's Beginnings

The two Mastiffs used to create the American Mastiff come from centuries old dogs, but is mostly comprised of the English Mastiff. There is a lot of debate over the Mastiffs origins but it has been around for at least 1000 years, possibly several thousand in the form of its ancestors. It is certainly one of the oldest English breeds and was bred as a dog of war, to attack enemy soldiers and in between wars to guard noble estates. They were once aggressive dogs and were also eventually used in bear baiting too. When it became socially less acceptable for guard dogs to rip intruders to pieces they were bred to hold them down instead, and when bear baiting was banned a lot of the aggressive traits of the English Mastiff were bred out of it. It became a gentle giant, protective and able to defend against threat, but a popular and affectionate companion also. Butchers especially kept them, as they had the meat to feed them! Numbers dropped though as new giant breeds came to England, and because of the cost of its upkeep.

For the other breed used in the mix, it is referred to by the breeder of the AM Mastiff as the Anatolian Mastiff but is in fact called the Anatolian Shepherd Dog and there is some claim it is a Mastiff and others say it is not. It was used to guard livestock in Easter Turkey for over 6000 years making it one of the oldest dogs in the world. While it not as friendly as the English Mastiff likely it was used because it has a longer life span than most giant breeds, it is healthier and it has the tight lips the breeder was looking for so it is not a heavy drooler.

Mastiffs came over to America with colonists on the Mayflower and continued to be imported from England over the years used for protection. It became a popular dog in the US, especially after World War II. But there were issues mostly from too much inbreeding, health problems, excessive drooling and short life spans to name a few, so a breeder called Fredericka Wagner in her kennels called Flying W Farms in Piketon, Ohio decided to breed a new Mastiff that was an improvement on that. She began in the late 1980s making the American Mastiff a very new arrival to the dog world. Throughout the 1990s she continued development on her dog with the Anatolian only being used at the start of the process giving the dog a ratio of 1/8 Anatolian and 7/8 English Mastiff. It is important to note she very carefully regulated who she bred the offspring with. Eventually she developed litters that are born with a lower lip line that is tight and she called her dog the American Mastiff.

New Lease on Life

At the end of the 1990s Wagner stopped outcrossing and was breeding from her existing lines. In 2000 the CKC, Continental Kennel Club gave her dog recognition and was the first organization to do this. In 2002 Wagner formed the AMBC (American Mastiff Breeder's Council) and allowed a few breeders to join that she was allowing to breed the American Mastiff. As of 2012 the council has just 11 breeder members and it works to make sure breeders conform to set rules for the dog's looks, health and temperament. As of yet they have not applied to any larger kennel clubs like the UKC or AKC for recognition, mostly because they would rather the breed stay a companion dog and not become a show dog to keep it healthy.


There is a lot of debate between English Mastiff breeders and American Mastiff ones, English Mastiff breeders do not approve of the American and will say the new breed is a failure pretty much. American Mastiff fanciers of course will argue otherwise. Being a new dog it will still be a few years until we know for sure about some of these things.

The Dog You See Today

The American Mastiff is a giant sized breed weighing 120 to 200 pounds and standing 28 to 36 inches tall. It looks similar to the English Mastiff but the American Mastiff is slimmer and less stocky. There is also difference in the face, with this dog having a longer muzzle, less wrinkles and does not appear as intimidating. AM Mastiffs have a huge muscular build still with thick necks that has a slight arch to them and long tails. It is deep chested, has a muscular straight back and has straight powerful legs and massive compact feet.

When born the American Mastiff is darker and then as the puppy matures they lighten. The coat is short and dense and common colors are shades of fawn, brindle and apricot. Some have white markings on the face, chest and feet, a black mask and some have some dark hairs that stay with them from being young. Its head is heavy, rectangular and wide with a medium length muzzle, tight lips, a drier mouth and a black nose. Its eyes are dark amber and its ears are set high and are rounded.

The Inner American Mastiff


The AM Mastiff is not aggressive unless it or the family is threatened. It does have strong protective instincts so when that happens it will act to defend you and its home. It is courageous in such incidents. It is a great loyal family dog, it is devoted to you, kind, gentle and patient and very affectionate. It loves to be around you and needs to be included in family activities and kept in the home rather than neglected outside. In fact despite being such a giant 'brute' it can even lean towards being clingy. Because of its size this is a dog best with experienced and strong willed owners who know how to handle giant breeds.

This is a sensible and quiet dog, it is more dignified than playful or joyful, but is is steady, loving and calm. It is not a breed to have around if you object to flatulence, snoring, some slobber and other noises and general messes you get with large and giant dogs. This is not a refined or delicate little flower! Around strangers it tends to be wary until it gets to know you so socialization is important. It is not eager to meet new people but most remain polite. It is alert and it is territorial so it will let you know if there is an intruder and it will defend its home making it a good watchdog and guard dog.

Living with an American Mastiff

What will training look like?

Training the AM Mastiff needs experience, as though the breed is intelligent and capable it is moderately hard to train. It is a stubborn breed and its size means it is easy for it to refuse to do something. It prefers to make its own decisions and do things its way rather than being obedient without question. It also is not a dog that responds well to lots of repetition. Therefore when training and socializing them keep sessions short and engaging, avoid too much repetition and be firm and in control.


Make it clear you are the boss from a young age and it will grow up accepting that. You need to be able to stay more dominant, be consistent and have some patience. Use positive techniques, using treats and such to motivate, reward, praise and encourage it. Early socialization means getting it used to different places, sounds, animals, other dogs, people and so on. It is important especially for a protective, territorial and large dog like this, that it knows how to recognize friend from foe, and real threats.

How active is the American Mastiff?

There is a certain level of physical activity that is needed for a dog of this size, it needs at least a couple of long walks a day along with some physical play with you somewhere. However it does adapt to how active its owners are, if you do more than those walks, maybe you hike for example it can join you. It needs to be at a walking pace though, this is not a dog that can maintain fast speeds for long. It should have access to a yard ideally and it will need mental stimulation too. If your American Mastiff is not getting enough exercise or mental challenge it will be destructive, loud, nervous and hard to live with. It does love to relax with you and will enjoy hanging with you in front of the TV at the end of the day.

Caring for the American Mastiff

Grooming needs

The coat is easy to groom being short but its size means the once or twice a week brushing can take some time! There will be no need for professional grooming but it does shed, and that can be anywhere from above average to heavy which means expect a lot of hair in the home, and on you. Some owners therefore opt to brush more often just to take care of some of that loose hair. If the idea of hair everywhere is something that bothers you in terms of cleanliness or even allergies this is not the breed for you. It should be wiped after it drinks and eats as this is when the drool is more likely to happen. This dog is meant to drool and slobber less than the English Mastiff but there is debate about that too. You can wipe down its coat to keep it clean and save baths for when it really needs it to avoid drying out its skin.

Its nails should be clipped if they get too long using proper dog nail clippers or scissors, and only cutting down to just before the quick of the nail where there are nerves and blood vessels. Should you go too far down it will hurt it and cause bleeding. Brush its teeth two to three times a week and clean its ears once a week taking care not to insert anything into them. Also check at the same time for signs of infection like irritability, redness and sensitivity. Wrinkles should be wiped clean regularly and kept dry.

Feeding Time

A giant sized dog will likely need to eat 8 to 12 cups of a good quality dry dog food a day split into two or three meals to avoid problems with bloat. How much exactly varies as it depends on size, age, health, rate of metabolism and level of activity. Make sure it has water that is changed often. Some mastiffs enjoy eating fresh vegetables so that can be given as a healthy treat too.


How is the American Mastiff with children and other animals?

The American Mastiff should get along very well with children especially with good socialization and if raised with them. It has a patient and gentle nature and is tolerant, affectionate and protective. However it is large and young kids will get knocked over. That protective instinct means socialization needs to cover rough play so the dog recognizes real threat. That socialization can help it get along with other pets but care should be taken still. It can live with other dogs fine but owners need to be clear leaders as dominance issues are always possible between two male dogs especially.

What Might Go Wrong?

Health Concerns

Part of the reason the American Mastiff was bred was to deal with some of the health issues the English Mastiff has. Breeders argue they had success with that, English Mastiff breeders say they did not. Being a recent development it is hard to say who is correct as yet, more time is needed. Issues to be aware of that the English Mastiff faces includes skeletal growth abnormalities, bloat, arthritis, breathing problems, lameness, eye problems, joint dysplasia, heart problems, skin problems, hypothyroidism and bladder problems.

Biting Statistics

Reports that detail attacks against people that did bodily harm over the last 35 years in Canada and the US do not make specific mention of the American Mastiff. However since it is a recent breed that is to be expected. There is a heading just labeled Mastiffs, not naming which ones in particular. Attributed to that are Attacks doing bodily harm: 28, Child victims: 23, Deaths: 5 and Maimings: 17. To minimize the chances of any incident make sure your dog is well exercised and given the attention it needs. Feed it properly and make sure it is well socialized and training.

Your Pup’s Price Tag

An American Mastiff puppy will cost about $1550 but since the breeders are few in number you can expect to be put on a waiting list. This is still far preferable to using cruel or ignorant options like puppy mills, pet stores or backyard breeders. There are lots of dogs looking for new homes in shelters and rescues so consider checking those out near you. It may not be an American Mastiff but you still can find great companions and best friends there for adoption fees of $200 to $400, and most have initial medical needs dealt with.

Once you have your dog wherever you have found it, there are things it will need. Initial items will cost about $265 for things like a collar and leash, crate, bowls and so on. If medical needs have not been taken care of by the breeder or shelter there will also be those costs to factor in. Initial medical needs includes things like neutering or spaying, micro chipping, blood tests, shots, deworming and a physical exam. These can cost somewhere around $290.


Then there are ongoing costs to consider, taking care of any pet is going to cost money, but a large one like this can cost more. Basic medical needs like shots, flea and tick prevention and check ups along with pet insurance is going to cost about $485 a year. Miscellaneous costs like license, basic training, miscellaneous items and toys will cost another $245 a year at least. Finally feeding a giant dog is a huge commitment. A good quality dry dog food plus dog treats will cost around $570 a year. This give an annual starting figure of $1300.


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There is a lot of debate going on about this new breed and a lot of bias from each side between the supporters of the American Mastiff and those of the English Mastiff. In time more certainty can be had about certain claims made from both sides about aggression, health, life span and temperament. So far it appears to be a decent dog, a devoted and loyal companion who is protective and needs attention and good exercise. It comes with usual issues with giant breeds so make sure you are confident you can handle it and them.

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