Rollover Dropdown Menu by v5.0.0 About The Mastiff



Origins and History

Click here to find a brief explanation of the origins and history of the breed.


Height and Weight

A Mastiff from England, Zorba, is listed in the Guinness Book of World Records as the heaviest dog in the world. At over 140 kg. Zorba was exceptional, but even so, Mastiffs are a giant breed of dog. 

In height, adult Mastiffs are usually 70 to 85 cm at the shoulder. This means that their head is at the height of an adult's hip. In weight, an adult Mastiff will generally weigh between 60 and 100kgs, more than many owners. On average, males will be taller and heavier than females but there are plenty of exceptions. A Mastiff puppy looks cute and cuddly but as you will realise from these figures, it will grow into a large and powerful dog.



Unfortunately, as with most of the giant breeds, Mastiffs are not particularly long lived. Their lifespan on average is between 8 to 10 years although there are a number of Mastiffs who live to be over 12 years and some who do not live to even 8 years.



Mastiffs grow to be very large dogs and their lifespan is not as great as many smaller breeds of dog. Mastiffs are slow to mature, both physically and mentally.

Although some never grow up

Physical Growth

It is generally agreed that Mastiffs do not mature completely physically until they are between three and four years of age. Because Mastiff puppies have so much growing to do and because size in an adult dog is desirable, this inevitably leads to Mastiff owners spending time comparing notes with others about the rate at which their puppy is growing.

Whether you are choosing your puppy or you already have your puppy, there are three things you should bear in mind about puppy growth rates. The first is that the rate at which a Mastiff puppy grows varies considerably from puppy to puppy. Some breeders are considered to have faster maturing lines than others but even puppies from the same breeder and the same litter may vary tremendously as to the rate at which they grow.

The second thing to bear in mind is that the rate at which a particular puppy grows will also vary over time. A puppy may go through a period of very rapid growth which leads to owners feeling that their puppy has quite literally grown over night. This may be followed by a period when the puppy doesn't seem to be growing significantly at all and then another growth spurt starts.

The third thing to bear in mind is that Mastiffs do not always grow evenly. For example, puppies that started out with a nice level back (topline), may go through a phase where they start to look like they are on a slope and their back legs are too long. Then they might level out again.


These three things mean that when you are choosing a puppy, you should always speak to the breeder about how they expect each puppy to develop. Then make your decision. Once you have your puppy, if you are at all concerned about the way it is developing, talk to your breeder or discuss your concerns with a vet who has experience of Mastiffs or other giant breeds. Also remember that you should never try to push a puppy to grow at a rate faster than the breeder and your vet recommend as this may seriously harm the puppy's long term health.

As a general guide to what to expect with a Mastiff puppy, you will notice a tremendous physical growth rate over the first 12 months or so. In that time most Mastiffs will grow close to their ultimate adult height. Over the next year to 18 months or so they will start to fill out and take on the solid appearance of an adult dog. After that, the growth changes will be more subtle but it is still necessary to keep in mind that they are probably still growing until they are about 3 or 4 years old.


As you will see, the standard says relatively little about temperament. However, because Mastiffs grow into such large and powerful dogs, their temperament is extremely important. A dog the size of an adult Mastiff which had an aggressive or nervous temperament could be extremely dangerous. A Mastiff should therefore be gentle, loving and loyal and their greatest pleasure should be to be with you.

To develop a good temperament, it is essential that a puppy come from a breeder who is aiming to breed a Mastiff with the correct temperament. It is also essential that the puppy you select appears to have a good temperament. These two things however, are only the starting point. The greatest influence on the outcome of a Mastiff's temperament is the treatment, training and experiences it receives throughout its life but especially as it matures to adulthood. On this point, keep in mind that a Mastiff matures slowly. While this will vary from dog to dog, it may take up to four years for your puppy to mature into the calm adult described in the standard and you will have to do plenty to help it get there.

The first thing you will have to do to help your puppy will be to give it plenty of time. Your puppy needs to be allowed to be with you. It needs to be under your feet as you work around your home and snoring its head off in your lounge as you sit there at the end of the day. Your puppy will not develop its special Mastiff personality if it is left outside away from you other than while you are feeding it and taking it for a short walk each day. Mastiffs need your time and they will richly reward you for it.

Your puppy will also need to be taught what is expected of it. It might be amusing seeing a Mastiff puppy trying to drag you around when you put it on a leash but it is no longer funny when it does the same thing as an adult who weighs more than you.

You should try and get out and about with your puppy as soon as possible so that it can start to learn to interact with other people and animals. Once you have started, keep doing it but also keep in mind that that your puppy also needs to spend time at home getting used to its surroundings and that puppies need plenty of sleep. Outings do not have to be long ones but they should be regular. Your puppy is most likely to grow into an adult Mastiff who is well socialised if it has had exposure to different situations and people on a regular basis and from an early age.

Part of the socialisation training it will need is to meet and mix with other dogs, of all breeds and ages. Mastiffs are generally very compatible with other dogs and seem to be particularly patient with small dogs. However, any breed of dog will get excited on seeing another dog if it does not normally have the chance to meet and mix. It is therefore important to condition your Mastiff to all varieties of dog so that it will not be fearful, dominant or aggressive when it sees another dog.

Mastiffs are not always overly confident and they can panic in new situations. During their development, all breeds of dog go through stages where they frighten easily and Mastiffs are no exception so don't be surprised if your Mastiff puppy suddenly starts to be scared of things that it has seen before. The best way to build up your puppy's confidence is to gently introduce the puppy to all manner of situations and to keep on doing it throughout your Mastiff's life. Introduce the puppy to different breeds and ages of other dogs, to travelling in the car, to children, to people in wheelchairs, people with walking sticks, people with umbrellas, people with hats, people with sunglasses, tall people, short people, loud people, crowds, traffic, trains, traffic overpasses' in short, anyone and any thing. But, don't try and introduce it to all these things at once. Make sure that the introductions are gradual and gentle so that it learns that new experiences are interesting and pleasant and not frightening. Do not reinforce behaviour that you do not want by "molly coddling" or trying to reassure your puppy - this only rewards behaviour that you do not want!

As a general guide to what to expect from your puppy's temperament as it develops, there are roughly three main phases to expect. The first stage is the puppy stage from the time you get your puppy (usually at about 8 weeks of age) up to 9 months or so. During this stage you can expect that, in general, you will have a happy friendly puppy. There will be periods when it may be scared of going near certain objects (for example, rubbish bins or grates in the footpath) but, in general it will recover quickly from these phases and you will enjoy watching its antics.

The second stage is from about 9 months through to 2 1/2 years or so and is equivalent to the human teenage years. While there are plenty of exceptions, your puppy may go through a period during this time which you will later refer to as the terrible teenage years. Your puppy will be reaching sexual maturity and will be trying to sort out its place in the scheme of things. As a result, it may sometimes behave in ways you did not expect it to. You may find your previously friendly puppy starts guarding you or your property or its food or that there are some altercations with other dogs that it has previously gotten on well with. You may find that it starts testing you out by, for example, not coming when it is called.

You may also probably find that your puppy starts behaving skittishly, taking fright at things or barking at people as they approach. You will need to be patient but consistent in continuing to teach your puppy what is expected of it and to introduce it to different people, places and situations and other dogs. Don't be surprised if, even though in many ways, your Mastiff is more loveable than ever, you sometimes wonder if you have made a mistake getting a Mastiff. Always speak to your breeder or other experienced Mastiff owners if you feel like this and they will be able to help you decide if you have a problem or whether your Mastiff is just being a teenager.

The third stage is from about 2 1/2 years of age on (but it could be later in some Mastiffs) when your puppy will hopefully have matured into the calm adult described in the standard. It will only have got there with a lot of hard work and help from you but you will now be sure that it was all worth it.


You can start gently teaching your dog what you expect of it from the time you take it home from the breeder. The aim of training is to help shape your Mastiff's behaviour to allow it to develop as a good companion while not suppressing its natural personality. An adult, not a child, should be primarily responsible for training, including house training a Mastiff, as with any dog.

Dog experts agree that it is during the period from six to sixteen weeks that a dog is most capable of learning. Perhaps even more importantly with a Mastiff, it the time when you are best able to physically control it. It is much easier to gently get a puppy to sit than to get a 70kg Mastiff teenager to do so. The difficulty is that during the period when your puppy is at the age when it is most receptive to training to shape its personality, the physical health of your puppy will not necessarily be fully protected by its inoculations. You will need to think about balancing the protection of the physical health of the puppy (which limits contact until it is fully protected by vaccination) and its long term mental health (which requires it to be able to socialise as much as possible).

You should therefore talk to your vet and your breeder about when they consider that your puppy's inoculations will leave it sufficiently protected to allow it to get out and about. Also speak to them about ways to get your puppy meeting other people and dogs and having new experiences even before it is fully protected. For example, your vet or local dog obedience school may run puppy socialisation classes where puppies that are not yet fully inoculated can play together.

You can also teach your puppy a tremendous amount about what is expected of it in your home. Think about the behaviour you want from your puppy and train him accordingly. For example, you may never intend to try competing in obedience competitions but you may still want to teach him to sit and drop on command. Both these commands can be useful when you take your adult dog to the vet and the vet wants to examine the dog's ears or the pads on the feet. At the same time, bear in mind that a puppy must be given the chance to behave like a puppy and you should not try nor expect to totally control its behaviour.

There are many training methods which have been developed for dogs and you should select a method which you think will suit you and your puppy. As a general rule, never use harsh training methods on a Mastiff. Mastiffs, particularly when young, are not overly confident and they are sensitive. They generally want to please you but they can also be incredibly stubborn. Kindness, consistency and lots of patience are what is needed to train a Mastiff and develop the wonderful Mastiff personality so training methods using positive reinforcement are generally the ones best suited to the Mastiff's temperament.



 Mastiffs are wonderful with children but, as with all dogs, they must be properly introduced, preferably at a very early age and they must always be supervised. You can not expect any dog that has not had previous experience of children to be immediately reliable with a child. In fact, dogs who have not had much contact with children quite often don't see them as being from the same species as adults. Their body proportions and the sounds they make are quite different. By the same token, you can not expect a child who is not experienced with dogs, to be reliable with your Mastiff.

Because they are smaller, children are more vulnerable than adults and, being large dogs, there is a greater potential for a Mastiff to cause harm to a child, even if only accidentally. A wagging Mastiff tail is powerful and also about the right height to cause plenty of pain if it hits a toddler in the face.

Children are also less sensitive to potential danger and they do not always understand that their actions may be causing an animal distress. For example, because their co-ordination is still developing, a toddler which is trying to pat a dog may in fact, from the dog's point of view, be whacking it rather than gently stroking it. While a Mastiff's natural instinct is to move away from a tormentor, you should never allow a situation to arise where this instinct is put to the test. It is your responsibility to ensure that children treat your Mastiff properly and do not knowingly or otherwise hurt or distress it.


You should also bear in mind that while Mastiffs make wonderful companions for children, because of their size, an able bodied adult will need to be responsible for exercising your Mastiff. A child and even a non-able bodied adult will have great difficulty controlling even a well trained Mastiff if it is being stubborn or playful. An adult will also need to be responsible for training.

Other Animals

Being naturally loving and gentle dogs who love companionship, Mastiffs get on well with other animals. There are Mastiffs who live harmoniously with all manner of other animals including cats, ducks and horses. As with children however, the Mastiff and the other animal need to be properly introduced and supervised, preferably while the Mastiff is still a puppy.


Because Mastiffs grow so much, they need large quantities of food and supplements while they are growing and particularly during the first 12 months. Once they have matured physically, the amount of food they require is much less. You will probably find in fact that, considering their size, they eat less than you would think. As a rough guide, as adults, they would generally eat no more than a medium sized dog of a more active type such as a German Shepherd dog.

When you collect your puppy from the breeder, the breeder will supply you with a diet sheet for the puppy. This will tell you what the puppy has been eating and how many meals it is getting. To avoid digestive upsets, you should try not to make any sudden changes to your puppy's diet. If you want to change its diet, introduce the changes gradually. Generally, it is preferable to follow the diet recommended by the breeder. Sometimes this will mean a bit of work but it is worth it to ensure that your Mastiff puppy develops properly.

As Mastiffs grow so rapidly especially during the first year or so, your puppy must receive the necessary amounts of nutrients during those months to avoid serious problems. At the same time, your puppy can also develop serious problems if it is overfed or over supplemented. If at any stage you are in doubt about your puppy's diet, discuss your concerns with the breeder or a vet experienced with Mastiffs or other giant breeds.

One other thing to bear in mind when feeding your Mastiff, is that it is generally recommended that the Mastiff's bowl be elevated off the ground to make eating more comfortable and to avoid splaying the front legs. Have your breeder show you what they recommend in this regard.



All Mastiffs drink a huge amount of water each day and they can become distressed very quickly, even in relatively mild weather, if water is not available. You must always ensure that there is fresh water available for your Mastiff at all times. The water must always be changed at least daily. You will also need to make sure that the water containers you use are ones that your Mastiff will not be able to knock over. Bear in mind when you select the containers that, as Mastiffs are very big dogs, containers which might not be knocked over by most dogs may not be able to withstand your Mastiff. Speak to your breeder and other Mastiff owners to get ideas on the best containers to use and try and have more than one just in case your Mastiff still manages to knock over the container you carefully selected.


Medications and Supplements

The dosage for most animal medications and supplements is based on the weight of the animal being treated. Because Mastiffs are such large dogs, this means that you will spend a lot more on veterinary treatment, medications and supplements for a Mastiff than you would for the same treatment for a smaller breed of dog. Regular worming and even treating a relatively minor condition in a Mastiff can be an expensive business because the dosage required is so high. Please consider whether you can afford the regular "running costs" involved in owning even a healthy Mastiff before you take that cute little Mastiff puppy home.



Especially when you first get your Mastiff puppy, do not expect that you will be able to spend hours and hours out and about each day. Mastiff are not a breed that spends the whole day on the go like some of the smaller working breeds. All Mastiffs spend quite a large proportion of the day asleep and, because they are doing so much growing, Mastiff puppies sleep even more than adult dogs. With your puppy you can expect that it will go through a short period of activity and then, quite suddenly, fall asleep for a couple of hours. It needs plenty of sleep to grow properly so make sure it is able to sleep when it needs to.

Being a heavy breed, a Mastiff's bones, muscles and ligaments are subjected to tremendous forces. It is therefore extremely important that you don't over exercise your Mastiff puppy and even your adult Mastiff. While they are growing, Mastiff puppies' bones are very soft and injuries can easily occur. As to how much exercise is safe for a puppy, this is, to some degree, a matter of opinion, even among those who are experienced with the breed. Most would agree however that your puppy will get sufficient exercise around your home and going on outings for socialisation. Certainly it would not need more than a gentle walk to supplement this and you should not be expecting your Mastiff puppy to accompany you jogging or going on long walks. Even on a gentle walk, always watch the puppy for signs that it is slowing down or tiring and don't keep pressing on further with a puppy that is tired.

It is a standard Mastiff owner's joke that that Mastiffs prefer to watch you exercise rather than joining in themselves so you don't need to be overly concerned about whether your Mastiff is getting enough exercise like you might with a more active breed. At the same time, Mastiffs do like a daily walk or two because it is an opportunity to get out and about. Also bear in mind that while over exercise can damage a Mastiff's health, so can being overweight so keep a close eye on your dog's weight and adjust the amount it eats to suit its level of activity.

You should also be careful to try and prevent your Mastiff puppy jumping. You will find, for example, that many experienced Mastiff people train their dogs to wait and be lifted in to the car rather than allowing their Mastiffs to jump in because they are so concerned about possible injury. You will find that they also supervise their Mastiffs around stairs because of the potential for injury if a Mastiff slips or falls.

If you are unsure about whether your Mastiff puppy is getting enough exercise or you think there is any sign that your puppy may be suffering from an injury, talk to your breeder or vet.

While there are Mastiffs overseas who participate in agility work, in Australia Mastiffs are not the ideal breed if you are interested in such work. Most agility clubs require dogs to be at least 18 months old before they start on agility work because of the harm which jumping can do to developing bones in any breed of dog. With the great weight of a Mastiff, you should wait even longer to ensure its bones are sufficiently mature so you will need to be very patient if you want to try agility with your Mastiff. You should also be aware that the rules for agility competitions in Australia take into account only the height of the dog, not the weight. This means that, unlike overseas, Mastiffs in Australia would have to compete over the same height jumps as much more lightly built large dogs.





While there are exceptions, in general, Mastiffs do not cope well with hot weather. They need a cool place to lie during hot weather and they will need even more fresh cool water than normal. You should not expect your Mastiff to be as active as normal during periods of hot weather and you should avoid exercising your Mastiff during the hotter hours of the day unless you are lucky enough to be able to exercise your Mastiff by swimming it.




Mastiffs are a relatively easy care breed. Their short coat needs only a quick brush a few times a week and may be a wash every few months to keep it looking good. Mastiffs do moult however. Some moult only a couple of times a year while others seem to moult continuously. If you happen to have a Mastiff who moults continuously, get used to the idea that you will always have Mastiff fur on your clothes, furniture and floors. The only other aspect to grooming a Mastiff is to trim your Mastiff's nails from time to time. You should start doing this from an early age so they get used to it. Your breeder will explain to you how to trim the nails and how much to trim off.



All Mastiffs slobber. The degree to which a Mastiff slobbers varies from dog to dog. Some dogs slobber only when they are eating, drinking or hot and there are others that hardly ever seem to stop. Most Mastiff owners never leave home without an old towel or something similar to use as a slobber cloth. If you have one of the ones that slobbers continuously, you will hardly ever put it down and will need it to wipe down your furniture, your walls and even your guests. No one likes slobber but if you can't stand it, the Mastiff is not the dog for you.



As with any breed of dog, there are certain diseases and health problems to which the Mastiff is more prone than some other breeds of dog. No breeder can guarantee that the puppy you buy will be disease free because the causes of many diseases are not fully understood. However, for diseases which are to some extent hereditary, there are tests which can be carried out on adult dogs which may help determine if puppies bred from those dogs are likely to be at risk from those diseases.


Hereditary Diseases

The main types of hereditary or partly hereditary diseases to which Mastiffs are considered to be at risk and for which adult Mastiffs can be screened are hip and elbow dysplasia, eye disease and thyroid disease.

Hip Dysplasia is a condition involving the abnormal formation of the hip joint. This can result in abnormal wearing of the hip joint causing lameness and pain in the rear legs. Generally symptoms will not appear until the puppy is 5 to 9 months old. X-rays are used to diagnose the disease and to try and screen for it in dogs to be used in breeding. However, some dogs who's X-rays show evidence of hip dysplasia never develop any actual symptoms of the disease while other dogs who's X-rays indicate normal hip formation may develop symptoms. Nevertheless, it is recommended that puppies should only be purchased from breeders who have had the Mastiffs they breed with hip scored. Ask to see a copy of the hip score report and discuss it with the breeder and your vet.

Elbow Dysplasia is a term used to describe a condition with a number of different possible causes. All of them cause abnormal wearing of the elbow joint resulting in stiffness, limping and pain and are believed to be caused, at least to some extent, by abnormal formation of the elbow joint. As for hip dysplasia, X-rays are used to diagnose the condition and to try to screen dogs to be used for breeding. Again, symptoms will not generally be apparent in young puppies. Most breeders have their dogs elbows X-rayed at the same time that they are hip scored. Ask the breeder whether this has been done and, if so, ask to see a copy of the X-ray report and discuss it with the breeder and your vet.

There are a number of eye diseases and conditions which are (at least to some extent) hereditary and can affect Mastiffs. They include entropion (which involves a rolling in of the eyelid resulting in the lashes rubbing on the eye), ectropion (which involves a rolling out of the eyelid), cataracts, persistent pupillary membranes (PPM) and progressive retinal atrophy (PRA). Each of the last three diseases can cause vision impairment and blindness. Screening for eye and thyroid diseases is often undertaken in the United States and some Mastiff breeders in Australia are now also starting to undertake such screening.


Other Diseases

Other diseases which seem to affect Mastiffs more than some other breeds include bloat and cancers.

Bloat is a build up of intestinal gasses which, if left unnoticed and untreated, can kill a dog within a very short time. Most deep chested breeds of dog are considered to be susceptible to bloat. Signs to watch for include swelling of the stomach, a hollow drum sound when the stomach is tapped, distressed pacing, restlessness and excessive panting. If you suspect bloat, take your dog to the vet immediately. Do not delay. Any delay may reduce the chance of successful treatment. To decrease the risk of bloat occurring, do not exercise your Mastiff for an hour before and after meals and feed an adult dog two smaller meals per day rather than one larger one. Be careful when selecting dry foods as some brands swell up more than others once they have been eaten. Some owners soak dry food so that it expands before the dog eats it.



The following books are recommended or those who would like to read more about the Mastiff breed:-

The Complete Mastiff
- Betty Baxter & David Blaxter (Ringpress Books Ltd.)

- Christina de Lima-Netto (Interpet Publishing)

The History & Management of the Mastiff
- Betty Baxter & Patricia Hoffman 
(Dogwise Publishing)

- Marie A Moore (T.F.H. Publications)

Mastiff: Aristocratic Guardian - dee dee Andersson (Doral Publishing Inc.)

The Mastiff and Bullmastiff Handbook - Douglas B Oliff (by Howell Book House)