Response to the Cavalier Petition on CM/SM

The following information has been collated in response to a petition asking the Kennel Club to make certain health screening for Cavalier King Charles Spaniels mandatory.  The Kennel Club ask that all those who signed the petition, or those who are passionate about the subject, read all of the information below in full. 

The issue of mandatory screening is not as black and white as it may appear - and whilst we were responsible for developing the health screening test that we are now being asked to make mandatory, we have good reason to believe that such action could be counterproductive - so we ask that you read the following material to help understand the Kennel Club's position and what it is doing, and what it recommends others can do to help improve the health of this breed.

What is being asked of the Kennel Club?

Over 28,000 people have recently signed a petition asking the Kennel Club to "Stop registering Cavalier King Charles Spaniel Puppies unless their parents are MRI scanned and heart tested".  The MRI scan in this instance is to check for Chiari-like malformations and syringomyelia (CM/SM), a very serious and unpleasant condition that can cause intense pain and neurological problems. There is currently no standardised heart test, although the Kennel Club, working in association with the University of Copenhagen and the Danish Kennel Club, has approved a new health testing programme for myxomatous mitral valve disease (MMVD) in the Cavalier King Charles Spaniel (more information here).

What is the Kennel Club's current stance on CM/SM screening?

In 2012 the Kennel Club and British Veterinary Association (BVA) introduced a screening scheme to enable a dog's MRI to be graded by a panel of expert neurologists and radiologists to help determine the degree of CM and SM.  The purpose of launching this scheme was to help reduce or eliminate the incidence of inherited CM and SM in dogs. 

The Kennel Club strongly recommends that breeders of Cavalier King Charles Spaniels screen their breeding dogs prior to mating.  Since CM/SM is a condition that develops and worsens over time, scans throughout the dog's lifetime are recommended, generally at year one, three to five years and over five years.

What factors have affected the Kennel Club decision on  whether to make the CM/SM screening scheme, that the Kennel Club itself developed, mandatory for anyone who registers with it?




The way that CM/SM is inherited is not currently understood so the health scheme will not produce definitive results about which dogs should or shouldn't be used for breeding, but what it will do is collectively build a picture about the breed, over time.

As such, while it is hoped that following BVA/KC breeding recommendations will help reduce the overall incidence of this condition, the MRI scans cannot be used to accurately predict whether the offspring of two screened dogs will be affected, nor to what degree of severity.  Two clear dogs may produce affected offspring, while two affected dogs may produce offspring that are clear. Making it mandatory could give false confidence to puppy buyers who believe that a puppy from clear offspring will also be clear.

Cost and risks of screening

The average DNA test may cost between £35 and £135, while a single MRI scan may cost around £500. The BVA and Kennel Club recommend that each breeding dog is MRI scanned three times throughout its life, costing around £1,500 in total. In addition, undergoing an MRI requires an anaesthetic which, while normally very safe, does carry some risk to the dog.

Given the costs and risks involved, the fact that the test will not give information that will accurately predict whether the puppies they produce will become affected or not, and that current research indicates that only 2 percent of the breed go on to develop clinical signs of the condition, we cannot insist that the test is mandatory. 

We can however, work with breeders who are passionate about improving the health of the breed to encourage and support those breeders in taking the test,  so that we can build a better picture about the disease, the mode of inheritance of the disease and how it can be reduced.

So, does using results from the health scheme appropriately prior to breeding guarantee that puppies will be free from CM/SM?

No.  CM/SM is a condition which is inherited in a complicated way which is not yet fully understood by scientists.  Affected breeding dogs can produce unaffected offspring, while unaffected dogs can produce affected offspring.  It is hoped that breeding appropriately from screened dogs will reduce the risk of producing affected offspring, but it must be stressed that this is not a guarantee.

By making CM/SM screening mandatory, the Kennel Club is concerned that puppy buyers who do their research and ensure that they buy from screened parents will have false confidence that the puppy they buy will not become affected in future.   This could then lead to people breeding from these dogs outside of the Kennel Club umbrella mistakenly thinking they are healthy, which could further a health crisis.

So if the test results will not tell you if puppies are affected what is the point of the test? How will it improve breed health?

The results of the health screening are critical to enable us to build a picture about the breed's health over time, and to offer solutions to this complex condition, whose mode of inheritance is currently not understood.

The Kennel Club employs a number of geneticists who will use the health information collected to develop of a genetic tool called Estimated Breeding Values, which is much more precise in enabling us to accurately determine genetic risk and understand the disease. We firstly need to work with breeders to encourage them to test and then we can produce these additional scientific resources that could further improve the chances of producing unaffected offspring. 

The Kennel Club believes that in order to reduce the incidence of CM/SM, breeders, breed clubs, puppy buyers, veterinarians, researchers and the Kennel Club must all work collaboratively.

The Kennel Club says that it will be detrimental to Cavalier health to make the health test mandatory, why is this?

The health test is not a legal requirement for Cavalier breeders and registration with the Kennel Club is only voluntary, so making the test mandatory will simply drive breeders away from the Kennel Club, meaning that we have fewer health test results and less information about the condition.

Instead, we need to take time to understand breeders' concerns about the test and support and incentivise them to use it. Because the test does not produce definitive results about whether puppies will be affected by the condition and because of the cost and risks associated with the test, we believe collaboration with breeders who are passionate about improving breed health will be much more effective than making the test a mandatory requirement for Kennel Club registration.

We are realistic and we know that not all breeders will wish to put their dog forward for testing, but we do not need large numbers to produce results and to build a picture about the health of the breed.

A further concern about driving breeders away by using a heavy hand and not listening to their concerns, is that they would no longer be able to make use of thefree health resources we provide to those who register a dog, use a dog for breeding, or are considering buying a puppy produced by a Kennel Club registered dog - meaning the power of these resources to improve breed health in other areas would be lost.  These resources include freely and openly published inbreeding coefficient calculators and health test results (such as BVA/KC eye test and DNA test results for Episodic Falling and Dry Eye/ Curly Coat)  - all of which improve breed health in other ways, so we must engage with breeders and understand their concerns about this particular health test, to ensure we can continue to improve the health of the breed overall.

It should be noted that Kennel Club registration figures for Cavalier King Charles Spaniels have decreased dramatically in recent  years, with 11,000 dogs being registered in 2006, compared to around 4,000 in 2014.  Although Kennel Club registrations for this breed have more than halved in ten years, the popularity of the Cavalier appears to be increasing, suggesting that thousands of dogs are being bred outside of the umbrella of the Kennel Club or breed clubs.  It is likely that Kennel Club registration figures represent only a small percentage of the total population and we could damage the breed further by driving away those breeders who we have the opportunity to collaborate with.

If you are not making the health test mandatory how are you going to persuade breeders to take it up?

The issue of CM/SM screening is complex and so finding solutions is complicated.  Rather than forcing breeders to screen, the Kennel Club believes that it would be more effective to:

  • Provide financial support for those who want to participate in the scheme which has started with the £30,000 the Kennel Club Charitable Trust and BVA have made available to anybody who wants to submit historical MRI tests for analysis. This means that we will get more results and at no cost to the breeders who are leading the charge and helping their breed
  • Improve and enhance educational resources for breeders, puppy buyers and owners to normalise screening
  • Develop our understanding of the condition and its spread throughout the breed
  • Work closely with breed clubs, breeders, owners, veterinarians and researchers to collaboratively tackle this problem.

What statistics are known about CM/SM?

A recent study carried out by the Royal Veterinary College found that 1.9% of Cavalier King Charles Spaniels had been diagnosed with SM, CM or both. 

Since the launch of the BVA/KC CM/SM scheme 195 Kennel Club registered dogs have been graded by the scheme.

Why are some breeders not CM/SM screening?

Looking at Kennel Club registration data reveals that only 0.28% of Cavalier King Charles Spaniel litters registered in 2013 and 2014 have come from parents that have both been BVA/KC graded.

CM/SM screening is very expensive, around £500 per MRI scan, and since the Kennel Club and BVA recommend three MRI scans during each breeding dog's lifetime, it would cost around £1,500 per breeding dog.  Although screening is expensive, and despite reducing the chances of producing affected offspring, it gives no guarantee that puppies produced from screened breeding dogs will be free from the condition. In addition, undergoing an MRI requires an anaesthetic, which, while normally very safe, does carry some risk to the dog.

Does the Kennel Club make health testing mandatory for other breeds?

Yes.  The Kennel Club is completely committed to mandatory health testing where this will improve the health of a breed and not have a negative impact, which is why where are 19 health tests and schemes for 91 different breeds that are compulsory under the Assured Breeder Scheme.

There are also breed-specific compulsory tests in certain breeds, which are put in place to eradicate breed-specific disease if it is strongly affecting the health of the breed.  These are known as Control Schemes and are mandatory for anyone registering a litter from breeds to which they apply.

 These schemes require owners to DNA test their breeding dogs before they are able to register any puppies from this mating.  The criteria for these mandatory testing schemes are that:

  1. We must know how the condition is inherited so that the test can give definitive answers as to whether the offspring will be affected
  2. The test must be accepted by a majority of breeders so as not to discourage breeders.
  3. A DNA test must be available, and must have been running as a voluntary official scheme for an average minimum of 12 months

Unfortunately the screening scheme for CM/SM does not currently meet any of these criteria.

What can breeders do to help further our understanding of CM/SM and to improve breed health?

The BVA and the Kennel Club Charitable Trust have pledged up to £30,000 to support dog owners concerned about CM/SM. This funding will allow owners who had MRI scans taken before the start of the BVA/KC CM/SM Scheme in 2012 to have their scans accessed by the scheme, and the results published for free - a process which would normally cost around £100.

To participate in this offer, MRI scans must have been taken before January 2012 and they must be from Kennel Club registered dogs.  Not all MRI scans are suitable for assessment.

To find out more about the offer:

Additionally, the current best practice is to screen those dogs being used for breeding, under the BVA/KC CM/SM scheme before breeding, at mid-age, and at an older age. By selecting those dogs who do not currently have the disease, or older dogs who show very minor or no signs of the disease, breeders are more likely to reduce the risk to puppies of passing on the most severe grading of this disease.


More information

Copyright © The Kennel Club Limited 2020. The unauthorised reproduction of text and images is strictly prohibited.