What do we know about Bulldog health

What health problems can some Bulldogs experience?

Bulldogs are a brachycephalic breed, which means that they have a flat wide shaped head (brachy, meaning short and cephalic, meaning head). This particular skull shape will often give these dogs a characteristic flattened face and a short muzzle. Muzzle length may vary, even amongst a particular breed, with some dogs having shorter muzzles than others. Although the shape of the head can make these dogs look very appealing, dogs with a very flat face and short muzzle may have a higher risk of developing certain health issues associated with these features, such as breathing difficulties, and eye, skin and dental conditions. In addition to the health concerns associated with their head shape there are other conditions that can affect some Bulldogs, such as urinary tract stones, heart issues and spinal problems.

Whilst we know that some Bulldogs suffer from these conditions, it is not known to what extent it affects the breed as a whole. The Kennel Club’s recent Breed Health and Conservation Plans research project has collected all available evidence based research to help us understand more about the health of this breed, with the aim of working with the breed to improve the health of the UK Bulldog population.

What do we know about the genetic diversity of the Bulldog?

In 2015 the Kennel Club published scientific research that investigated the rate of change of genetic diversity of all our registered breeds, including the Bulldog. Our effective population size research found that the breed suffers from challenges in relation to genetic diversity, which could impact the long-term health of the breed. It was found that the rate of inbreeding was at its highest in this breed in the 1980s and

1990s, but the rate of inbreeding has since slowed and even been negative, implying a slowdown in the rate of loss, and modest renewal, of genetic diversity (possibly through the use of imported animals).

Is there enough genetic diversity in the breed to tackle health problems, or should the breed be outcrossed?

It is important that we incentivise breeders to use the resources being developed by the Kennel Club and others, which are the only way to improve the health of the breed.

Whilst the Kennel Club has supported outcrossing where this is necessary for a breed, there isn’t any reliable research which indicates the outcrossing is the only or even a necessary solution for the breed, at this stage. The idea that the gene pool might be too limited to be saved comes from a scientific paper by Professor Niels Pederson.

Whilst any research that helps us to get a picture of dog health is useful, this research has some serious limitations, which gives dog lovers an incomplete picture of the realities of Bulldog health.

The small number of Bulldogs sampled were primarily based in America and how they were related to each other was not recorded, which would influence any conclusions about genetic diversity – so we can’t on this basis make assumptions about the genetic diversity of all Bulldogs, and the UK population in particular.

Our research into the genetic diversity of the entire Kennel Club registered population of Bulldogs (based on Estimated Effective Population Sizes), shows very real challenges, but also that the rate of loss of genetic diversity has slowed down in recent years and there has been a modest replenishment, possibly from the use of overseas dogs.

We need to help breeders carefully balance the need to select healthy Bulldogs, with avoiding the loss of genetic diversity, and our online Mate Select program and inbreeding calculator helps breeders to do this.

It is important to remember that there are healthy Bulldogs - the researchers at the University of Cambridge who are looking at Brachycephalic Obstructive Airway Syndrome have found that not every Bulldog suffers from health problems, which means that careful selective breeding by responsible breeders could see certain health problems eliminated from the breed.

Would the Kennel Club allow the outcrossing of the Bulldog in order to improve genetic diversity?

The Kennel Club supports outcrossing where it will help a breed, and there are various examples of Kennel Club registered breeds where outcrossing has occurred (eg Irish Red and White and the Irish Setter, inter-variety Belgian Shepherd Dog matings, the Bull Terrier to the Miniature Bull Terrier and the registration of progeny from a Dalmatian/Pointer mating, for a low uric acid (LUA) gene) - but we must ensure that any decisions are made on the basis of good science in order to avoid making the situation worse, or introducing problems that don’t currently exist.

Outcrossing can have a positive effect but it is not a silver bullet. When you bring a dog with a desirable gene into a gene pool it will itself become a common ancestor to all dogs with that version of the gene, so does not mean you can stop managing inbreeding.

Furthermore, if you get breeders who favour the dog with the outcrossed characteristics and others who favour those without it you could split the breed in two, reducing genetic variation still further. So we need to work carefully with breeders to ensure our actions are not counterproductive.

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