Merle Bulldogs - What you need to know about Merle English Bulldogs

Merle Bulldogs - What you need to know about Merle English Bulldogs

Breed Facts

The Bulldog(or English Bulldog as its know in some other countries) is an instantly recognisable dog breed, and one that is very popular all over the world as well as of course right here in the UK. This is one of our longest established native British dog breeds, and one that has ultimately become an international symbol of all things British thanks to its unmistakable appearance and distinctive temperament.

The English bulldog is actually the 7th most popular dog breed in the UK overall (as of 30th Jan 2019), and one that is in great demand among prospective puppy buyers looking for a new dog; but the breed is also quite a complex one that is widely associated with a number of hereditary health and conformation issues that can have a significant impact on the health and longevity of individual dogs.

The appearance of the English bulldog has changed quite significantly over the course of the last century or so too, and the build and conformation that is widely considered to be acceptable or desirable within the breed now is rather different to that displayed by dogs from as recently as a few decades ago.

As demand for English bulldog puppies is so high, there are a large number of English bulldog breeders in the UK who breed bulldogs to meet this demand, and some of them specialise in so-called rare or unusual English bulldogs. These may display highly exaggerated physical trails (such as heavy wrinkling or an excessively flattened face) or have an unusual colouration that is not usually found within the breed.

One such English bulldog colour that is not naturally found within the breed but that has been introduced into some breed lines is called merle – and merle English bulldogs are highly sought after by puppy buyers, and tend to attract high prices to match.

However, there is much more to merle English bulldogs than just a distinctive colour, and merle coloured English bulldogs may also inherit health issues alongside of the genes that cause this distinctive colour and pattern combination.

This means that the very existence of merle English bulldogs at all is highly controversial, and anyone who is considering buying a merle English bulldog is cautioned to find out all about the implications of the merle genes before committing to a purchase.

In this article we will provide a detailed introduction to merle English bulldogs, and explain how merle appears within the breed, what it means for dogs of this colour, and why there is a lot of controversy about the existence of merle English bulldogs at all. Read on to learn more.

What is a merle English Bulldog?

A merle English bulldog is simply an English bulldog that comes in a particular colour type called merle. Merle is described as a coat colour and pattern combination that can be seen across several different breeds of dog, and which results in a coat with patches of mottled colour across an otherwise solid coloured or piebald coat.

The merle pattern and colour are also sometimes reflected in the pigment colour of the dog’s skin as well as their coats, and may result in the dog having blue eyes, or odd eyes with one of them being blue. Merle colouration in the English bulldog may also be accompanied by hereditary health problems, and we will expand on these in more detail later on.

Does the merle colour appear naturally in the English bulldog breed?

The question of whether or not merle English bulldogs appear naturally rather than as the result of the introduction of specific genes (from other dog breeds) that carry the merle markers is one that is the cause of some argument; many merle English bulldog breeders will argue strongly that the colour can and does occur naturally within their breed lines.

Whilst genetic mutations (such as those that lead to new or unusual colours and other traits) can and do occur naturally in purebred breed lines of dogs of all sorts, this is very rare. Even if this has theoretically happened at some point in the past within English bulldogs and resulted in a merle being born (and there is no evidence to suggest that it has) this type of spontaneous genetic mutation does not occur often enough to result in the natural development of merle strains within the wider English bulldog breed in significant numbers.

The Kennel Club and formal English bulldog breed organisations that prioritise breeding for health and breed improvement state that merle is not a naturally occurring colour within the breed, and that it cannot be present in true dogs of the breed without being introduced to the bloodline by means of outcrossing.

Merle English bulldogs are produced as a result of selective breeding to achieve this uncommon colour, and the merle colour is not one that is considered to be a naturally occurring phenomenon within the breed.

What are the standard English bulldog colours?

The Kennel Club (in association with recognised English bulldog breed organisations) provides clear guidance on the colours that can be found naturally within the English bulldog breed, as well as those that are specifically forbidden or not recognised.

The standard and accepted English bulldog coat colours as per the UK Kennel Club are:

  • Brindle
  • Brindle and white
  • Fawn
  • Fawn and white
  • Fawn brindle
  • Fawn brindle and white
  • Red
  • Red and white
  • Red brindle
  • Red brindle and white
  • Red fawn
  • White
  • White and brindle
  • White and fawn
  • White and red

As you can see, there are quite a number of different natural coat colour and pattern combinations to be found across the English bulldog breed as a whole, but there are also a number of colours that are specifically mentioned by the Kennel Club as falling outside of the breed standard. These colours are:

  • Dudley (liver-coloured lips, noses, eyelids, tongues, and foot pads)
  • Black
  • Black and tan
  • Black, white and tan
  • Chocolate

However, whilst these colours are not accepted within the English bulldog breed standard (and are in fact considered to be “highly undesirable” colours within the breed) they are not associated with an increased risk of potential health problems in dogs that possess them.

This means that dogs displaying these colours are still eligible for Kennel Club registration as pedigree English bulldogs, but that their colour is classed as “colour not recognised by the Kennel Club” and notated as such on their pedigree records.

Can merle English bulldogs be Kennel Club registered?

You may have noticed that merle English bulldogs are not mentioned on either of the lists above – neither within the acceptable English bulldog colours nor those that are considered to be undesirable but permitted.

This is because the Kennel Club has a specific policy that is applied to only merle English bulldogs, which is that they are not eligible for pedigree registration full stop. The Kennel Club in the UK won’t permit dog breeders to register merle English bulldogs within the breed registry, which means that they are not afforded pedigree dog status and all of the advantages that this infers – they are not classed to be pedigree dogs as they are not acceptable within the breed.

What does the Kennel Club say about merle English bulldogs?

The Kennel Club takes a very strong stance against the existence of merle English bulldogs by refusing to recognise and register them, and this is outlined within the breed-specific restrictions applied to the registration of English bulldogs.

The Kennel Club’s position on merle English bulldogs is that the merle coat pattern does not occur naturally within the English bulldog breed, and that the health concerns associated with merle English bulldogs mean that the introduction of this colour is detrimental to the breed as a whole (as well as to individual dogs) and so merle English bulldogs cannot be Kennel Club registered.

This refusal to register merle English bulldogs applies to both dogs bred within the UK, and those imported from abroad.

The Kennel Club’s formal statement on merle English bulldogs states that the merle pattern occurs due to the presence of “M” genes, which come in two forms: Big M (M) for merle, and little m (m) for non-merle. The big “M” gene is dominant over the little “m” non-merle gene, and the presence of the M gene can lead to an increased risk of the dog also inheriting a range of health problems along with their distinctive colouration, such as hearing and vision problems.

What if an English bulldog breeder claims that their merle English bulldogs are Kennel Club registered?

As we explained earlier on, whilst there are various undesirable and unrecognised colours that can be found in English bulldogs that fall outside of the breed standard but that do not disqualify the dog from eligibility for registration as “colour not recognised,” merle English bulldogs cannot be registered with the Kennel Club at all, even under the “colour not recognised” option.

However, a small number of unscrupulous merle English bulldog breeders claim that their breeding stock are registered with the Kennel Club despite this; and not all prospective merle English bulldog puppy buyers know about the merle restrictions and so, spot the incongruity here.

If a merle English bulldog breeder claims that a dog for sale is registered with the Kennel Club, something is amiss – and there are a couple of ways in which unscrupulous dog breeders might try to bypass the restriction on merle English bulldog registration to get their dogs registered for pedigree papers, and mislead puppy buyers.

The first and most common approach to fraudulently registering a merle English bulldog is to use the “colour not recognised” designation, implying that whilst their dog is not a standard colour, they are still eligible for registration.

An alternative to this is that the dog may be registered as one of the specific named colours rather than as “colour not recognised,” which is just as fraudulent.

A final method that some merle English bulldogs use to try to add a layer of authenticity to their sales (and often, in order to increase sale prices) is to register their puppies with a breed registry other that the formal UK Kennel Club.

The Kennel Club is the UK’s umbrella authority for pedigree dogs and dog breed registration, but it is not the only one; there are a fair number of other breed registries in other countries (many of which are on a par with our own Kennel Club, such as the AKC or American Kennel Club in the USA) and also, international registries that will register dogs from more or less anywhere in the world.

Whilst some such registries are highly regarded and widely recognised both inside and outside of the UK (like the AKC), anyone can in theory set up a breed registry, give it a grand-sounding name, and open its books to dogs of a wide range of different types that may not be recognised or accepted by formal registries.

Some of these are designed to be more inclusive of new dog breeds that are currently not recognised by major breed registries, and/or to enable breeders to register puppies that might not otherwise be eligible for Kennel Club registration in order to improve the perceived value of their pups.

If an English bulldog breeder states that their merle English bulldogs are registered with pedigree papers, first check exactly what organisation they are referring to as having issued the paperwork, as they are unlikely to be referring to the Kennel Club.

If the breeder maintains their claims that their merle English bulldogs are Kennel Club registered with papers, this is either fraudulent, or a lie; too many puppy buyers take breeder’s claims at face value, and get caught out by being told that the dog has pedigree papers that ultimately never fail to materialise or keep getting “lost in the post.”

Breeders caught attempting to deceive both the Kennel Club and puppy buyers by bypassing restrictions to register merle English bulldogs should be reported to the Kennel Club. If you spot any adverts here on Pets4Homes claiming to advertise Kennel Club registered merle English bulldogs, please also use the “report” link within the advert itself to let us know, and we will respond accordingly.

Can you enter merle English bulldogs in dog shows?

Merle English bulldogs are ineligible for Kennel Club registration, which means that they are also ineligible for entry into Kennel Club affiliated dog breed shows.

You cannot enter a dog that is not registered with the Kennel Club in a Kennel Club dog show, because they are not recognised within the English bulldog breed standard.

If a merle English bulldog has been fraudulently registered with the Kennel Club as being “colour not recognised” or as another named colour, they will be disqualified on the day and removed from the breed registry too.

When did merle English bulldogs first appear?

As mentioned, the merle colour genes are not genes that appear naturally within the English bulldog breed, and in order to introduce them to a breed line, dogs need to be outcrossed to dogs that do carry the merle genes.

This means that a merle English bulldog will have at least one ancestor (even if this is a long way back in the breed line) that is not a purebred/pedigree English bulldog, and may even be traced back to genetic input from a different dog breed altogether.

Because the genes that result in the merle colour in dogs are dominant, it is easy to spread this colour trait through a breed population – just one parent dog that is merle can produce merle puppies, regardless of the colour of the other dog in the mix. This means that the mixed-breed ancestor (or ancestor of another breed) might appear way back in any given dog’s family tree, and you may never know for sure when this happened, or what type of dog it was.

People have been planning mating matches and breeding English bulldogs selectively to introduce and reproduce specific traits (like unusual colours) more or less ever since we first began breeding dogs deliberately; we don’t know when or why the very first merle English bulldogs were bred, or if this was achieved deliberately or occurred as part of a mating mis-match.

However, the existence of merle English bulldogs in large numbers, and demand for them among puppy buyers is a relatively modern phenomenon, which only really began to pick up speed in the last decade or so.

The genetics of merle inheritance

So, how does the heredity of the merle coat colour in English bulldogs work, and how is the merle colour trait passed on from parent dogs to their young?

Merle is a heterozygote of a gene that has incomplete dominance, and understanding the various different ways that this gene may behave and so, manifest in individual dogs can be quite complex, and requires a reasonably advanced level of understanding of genetics.

Here are the basic facts of merle inheritance in the English bulldog breed.

There are two merle genes, being big M and little m, and dogs that inherit just one copy of the big M gene (from one of their parents alone) may well end up with a merle coat. Because the dominance of the big M gene is incomplete, they may also inherit a non-merle coat instead, and some litters will contain a mixture of both merle and non-merle dogs.

Dogs that inherit one or two copies of the little m gene without a correlating big M gene will not have a merle coat.

If a dog inherits two copies of the big M gene – one from each of their parents – they will display what is known as a double-merle colouration, and this comes with a greatly heightened risk of associated health problems over and above the risks present for dogs with a single merle gene.

There are also a number of sub-variants of merle colours that can be found in some dogs too, including cryptic merle (which results on only small patches of merle colouring) and harlequin merle, among others.

Merle English bulldog health issues

As we have mentioned earlier on within this article, merle English bulldogs have a significantly higher chance of inheriting a range of conformation defects and hereditary flaws alongside of their merle colouration, which is the basis of the main objections made against the colour’s presence within the breed at all.

The English bulldog breed as a whole (regardless of the colour of its individual dogs) is one that is strongly associated with risk factors for a wide range of hereditary health conditions, ranging from BOAS or brachycephalic obstructive airway syndrome through to skin and coat allergies, patellar luxation, eye problems and heart defects, and many others besides. You can read more about the full range of potential health problems that can be found within the English bulldog breed here.

Additionally, English bulldog puppies usually have to be delivered by caesarean section due to the relative size of the pups’ heads compared to the dam’s pelvis, and some English bulldogs require assistance with mating too, due to the narrowness of the dog’s hips.

When it comes to merle English bulldogs, there are a number of health issues that pertain specifically to dogs of the breed that are merle coloured, and which can be inherited alongside of the genes that cause the distinctive merle coat colour to be present in the first place.

The merle colour in English bulldogs is associated with a heightened risk of hereditary deafness that may affect either both ears or just one, and that can be either partial or complete. Additionally, English bulldogs with merle colouration may also suffer from blindness or poor eyesight, and may have abnormally formed or improperly developed eyes.

Neither deafness nor vision problems automatically occur in all merle English bulldogs, but they do manifest in a significant enough number of merle dogs to be considered to pose a threat to the quality of life of affected dogs, and the health of the breed as a whole.

Merle colouration can also cause a lack of pigmentation across certain areas of the skin, and may also lead to an increased risk of the dog developing skin cancer or hypersensitivity to light.

Double merle – double the risk?

Whilst there are serious potential health implications for merle English bulldogs that should not be minimised or discounted in your enthusiasm to find the right puppy, these health problems only affect a relatively small percentage of all merle English bulldogs.

However, when it comes to double merle English bulldogs, the risk factors increase exponentially – and if merle English bulldogs are considered to be risky in terms of their health, this risk really goes into overdrive when double merle is involved.

A double merle English bulldog is one that inherits the big M merle gene from both sides of their parentage instead of just one, and all dogs that inherit two copies of this gene will display a double-merle coat. The majority of double-merle English bulldogs inherit serious vision and hearing issues, and around a quarter of all such dogs will be both completely deaf and completely blind.

Breeding merle English bulldogs might be highly controversial due to their association with health defects – but double-merle English bulldogs are objectively an even bigger problem, and such dogs generally have a poor quality of life, and a greatly heightened risk of a variety of complex health problems.

What do bulldog breed organisations say about merle bulldogs?

There are a number of different English bulldog breed clubs and advocacy organisations, and some of these are recognised by the Kennel Club as partners or affiliates, who work with the Kennel Club to monitor and improve upon the breed’s health and standards.

No reputable, Kennel Club affiliated bulldog breed organisation accepts the breeding of merle bulldogs, encourages this practice or recommends merle English bulldogs as good pets, and breeding or buying merle English bulldogs is usually specifically discouraged or forbidden within the organisation’s code of ethics and guidance on good practice for breeders and puppy buyers.

The Bulldog Breed Council specifically cites merle as an unethical colour within the breed, and one that should never be encouraged or rewarded; and all of the breed council’s own recognised affiliates and regional member clubs hold the same policy.

Counter-arguments from merle English bulldog breeders

Despite the formal policies that the Kennel Club and bulldog breed organisations hold regarding the problems with merle English bulldogs, there are still a reasonable number of breeders in the UK deliberately producing merle English bulldogs to meet the high level of demand for dogs of this type.

Such breeders often target the uninformed puppy buyer who has no idea of the potential merle bulldog issues, or who rush to purchase a desirable dog. Some breeders may make somewhat outlandish claims about the puppies that they are trying to sell, which will often be in direct contradiction of the facts, and the formal viewpoint taken by the Kennel Club and bulldog breed clubs.

First of all it is important to note that it is entirely possible that a merle English bulldog puppy will be as healthy as any other dog of the breed, and not found to be suffering from eye, ear or other congenital defects. There is no debate over the fact that merle English bulldogs can inherit merle colouration without the correlating health problems that sometimes accompany it.

If a merle English bulldog breeder claims that any individual merle dog they own is healthy, this might well be true (although you should never take this at face value). However, every merle puppy bred has a risk of inheriting the aforementioned health problems, and there is no way to breed merle English bulldogs without risk.

Any given pup from any given litter may have health defects if they have the merle colouration, and a breeder has no way of knowing when they mate any two dogs to produce merles whether or not any of the pups will inherit those problems along with their colouration.

This means that even if you do find and choose a merle English bulldog that is itself perfectly healthy, other pups from their same litter or that were bred by the same breeder may possess those same health problems.

Ultimately, that means that by buying a merle English bulldog – or even a non-merle English bulldog from a breeder that produces merles – you are supporting the ongoing breeding of ever-more merle dogs, with ever-more potential health problems.

How common are merle English bulldogs?

It is a simple fact that uncommon or unusual-looking dogs are in great demand among puppy buyers, and this in turn incentivises breeders to selectively breed dogs to meet this demand, even sometimes at the expense of good health and breed improvement.

Merle English bulldogs are commonly advertised as being hugely rare, unique, special, or otherwise distinctive, often citing long and impressive-sounding ancestries containing numerous handsome-looking merle dogs.

Merle English bulldogs should indeed be rare, because they shouldn’t actually occur at all – but given the number of breeders seeking to produce them, how rare are they really?

At the time of writing (January 2019) there were a total of 582 English bulldogs for sale advertised here on Pets4Homes. Of those 582 dogs, just 17 were advertised as possessing the merle colouration – which represents a total of just under 3%.

Based on these figures, it is certainly fair to say that merle English bulldogs are rare; largely because both genuinely responsible English bulldog breeders and those that are concerned about their public image will not breed merle English bulldogs due to their health concerns and widespread negative opinion on the practice.

This does mean, however, that those breeders who are prepared to go ahead with breeding merle English bulldogs anyway despite the risks and bad publicity that can accompany them, often market their dogs by highlighting their rarity and perceived higher value as a result of this.

How much do merle English bulldogs cost to buy?

English bulldogs are quite expensive to buy even in accepted and standard colours, and at the time of writing, the average advertised price for English bulldogs here on Pets4Homes is £1,514 for non-Kennel Club registered English bulldogs, and £1,704 for registered English bulldog puppies.

The high sale price of English bulldogs reflects a range of different factors, one of which is of course the perceived desirability of the breed and the level of demand for them among puppy buyers.

However, breeding English bulldogs is quite an expensive practice in and of itself, and even breeders that successfully sell all of the pups in their litters at the asking price may only just break even, or even make a loss.

Purchasing good quality breeding stock in the first place is expensive, then you have to factor in the cost of keeping the dogs, performing pre-breeding health tests, removing and caring for dogs that don’t pass their health tests from the breeding pool or sale, and the cost of arranging mating, the litter’s delivery, and veterinary support too, to name just a few things. English bulldogs also tend to produce relatively small litters, with just two or three pups being quite common, and often, this is not enough to cover all of the costs involved in breeding them.

When it comes to merle English bulldogs, they often tend to attract prices far in excess of even the relatively high prices commanded by standard-coloured English bulldogs. There is quite a degree of variation between the prices of different merle English bulldogs, with double and even tri-merle dogs sometimes being advertised for less than regular colours, due to the health conditions that go with this colour combination.

The highest advertised asking prices for single merle English bulldogs at the time of writing fall around the £10,000 mark, and merle English bulldogs priced at around the £3,000-£5,000 mark are common too.

Are merle English bulldogs appealing targets for thieves?

The idea of someone stealing our beloved dog is one that most owners prefer not to think about, but dog theft is a very real threat all over the UK, and when it comes to unusual and particularly valuable dogs, the risk is even greater.

English bulldogs are one of the most desirable breeds for thieves to target, regardless of the dog’s colour; because there is a lot of demand for them and they often change hands for large sums of money.

Stolen English bulldogs may be resold as pets, used as breeding stock or even sold to dog fighting rings – but this latter is less common than many people fear, particularly when it comes to high-value dogs, as they can be sold on so easily for a quick profit without the associated additional risk of participation inherent to involvement in dog fighting operations.

Because merle English bulldogs are relatively rare, they are even more appealing targets for theft. This may be because opportunistic thieves simply see a handsome dog and decide to take it, or because they know that unusual dogs can attract higher prices.

Sometimes, dog thieves steal dogs to order, and deliberately target specific types of dogs that they know they have a waiting buyer for.

Whilst few genuine dog lovers would knowingly buy a stolen dog, every year, many people inadvertently do buy one (or a pup bred from a stolen dog), and the lack of pedigree paperwork accompanying what otherwise appears to be a pedigree dog is often a warning here.

Because merle English bulldogs cannot legitimately have pedigree paperwork in the first place, prospective puppy buyers who are aware of this see the lack of paperwork as going with the territory, and do not realise that this very trait may help to make reselling stolen merle English bulldogs that much easier.

Many also go to great lengths to produce forged registration documents, or provide registration documents from one of those unknown or informal “breed registries” that we mentioned earlier on.

Should you buy a merle English bulldog?

Whilst the Kennel Club and all responsible English bulldog breed organisations take a strong public stance against merle English bulldogs, they are still totally legal to breed, buy and sell in the UK.

However, the question of whether or not you should buy a merle English bulldog if you like them is one that every individual has to ask themselves carefully, taking into account all of the pertinent factors.

Here are the key points to bear in mind.

  • Merle is more than just a colour – it is a combination of genes that have implications for health defects as well as coat colour.
  • Merle English bulldogs cannot be registered with the Kennel Club. If a breeder claims that their merle English bulldogs are KC registered, this is either untrue or fraudulent.
  • Merle English bulldogs are not accepted by nor recognised by any of the responsible English bulldog breed clubs.
  • Merle English bulldogs cannot be entered in formal Kennel Club dog shows.
  • Merle English bulldogs have heightened risk factors for ear and eye problems, which can result in deafness or blindness. They also have elevated risk factors for sun sensitivity and skin cancer.
  • Double-merle English bulldogs have a much greater risk of health problems, and rarely enjoy a very good quality of life.
  • Merle English bulldogs tend to be prohibitively expensive to buy.
  • Lower-priced merle English bulldogs should not be seen as a potential bargain – their low sale price may well reflect the presence of health problems or conformation defects, which makes them harder to sell.
  • Even if you do buy a healthy merle English bulldog, by doing so you are contributing to demand for dogs of this type and encouraging breeders to keep producing them. This can and does result in more and more dogs being born with health problems, and has a knock-on effect on the health of the wider breed as a whole.
  • Because merle English bulldogs cannot be registered with the Kennel Club, they are not subject to the breeding regulations and restrictions placed on registered dogs. This means that there is no mandated limit to the upper or lower age at which such dogs may be bred, no health testing recording protocol in place, and no limit to the number of litters any dam may have, either within a given timeframe or over the course of her life. All of these factors have implications for the wellbeing, health and quality of life of the breeding stock.
  • Merle English bulldogs are a desirable target for dog thieves, due to the high level of demand for them and the correlating high prices that they often command.

If you have your heart set on owning a merle English bulldog, you should ask yourself seriously why this is; the temperament of the dog and the other core English bulldog traits that their owners value are all present within standard coloured English bulldogs too.

Adopting or rehoming an older merle English bulldog might be a viable alternative – this enables you

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