Colour Dilution Alopecia – not so simple!

In the last week of April, I had the pleasure of chairing another of The Kennel Club’s webinars, organised by the Health Team. It was a free webinar for owners and breeders who wanted to find out more about the dangers of breeding for fashionable colours, using the example of colour dilution alopecia – including what research has told us to date, and how best to support dogs affected with this condition.

Colour Dilution Alopecia (CDA) is a genetic condition found in some breeds that causes hair thinning and loss, which can leave the skin prone to sunburn, infection and dermatitis. The condition is associated with dogs who have a “dilute” colour (e.g. blue, lilac, isabella or silver). While the disorder is commonly described in Dachshunds and Dobermanns, it has also been recognised in other breeds. With the rise in popularity of “fashionable” coloured dogs, it’s crucial to understand the dangers that can be associated with breeding for certain colours and what breeders can do to try to reduce the prevalence of conditions associated with dilute coat colours.

My introduction to the webinar shared some data on the 2021 registration statistics of those breeds where there are Non Breed Standard (NBS) colours in their registration options. This applies to about 10% of the KC’s registered breeds. At one extreme, French Bulldogs had 70% of their 2021 registrations as NBS and 53% for Bulldogs. Labradors had 1% NBS but, with over 61,000 registrations, that still amounts to over 800 NBS dogs.

Colour Dilution Alopecia is a concern to many of us in the Dachshund community because it is reported in the dilute colours (blue and isabella). We ran a breed health survey in 2021, supported by The Kennel Club, specifically to find out how prevalent the condition was. Our 2018 survey had shown skin diseases and allergies to be the second most prevalent health concern in all colours (after IVDD – back disease) and we wanted to find out if this was a particular issue in the increasingly popular dilute colours. Most people will be aware that Mini Smooth Dachshunds have grown in popularity over recent years (under 3000 registered in 2013 and over 15000 registered last year). Shockingly, registrations of dilute Mini Smooths have grown from 0.1% in 2018 to 20% last year. Not only has the breed become extremely fashionable, but “rare” colours have too (often aided by the influence of social media).

In Fitch Daglish’s 1952 book “The Dachshund”, he refers to blue dachshunds, so it is clear that the dilution gene has been in the breed for a very long time. This is not something that has been added by cross-breeding. The high number of dilute puppies now being bred is down to intensive selection for the dilute coat colour in the UK population. Our 2021 health survey showed 80% of blue dachshunds were affected by CDA and 86% of isabellas.

Dr Rosario Cerundolo (Head of Dermatology at Dick White Referrals) presented during the webinar on the signs, diagnosis and treatment of CDA. He showed examples of the condition in several breeds, including Dalmatians, Russian Toy Terriers and Dachshunds. Electron microscope images illustrated the structure of hairs in dilute dogs that causes patches of hair thinning or loss and may also include flaky and/or itchy skin. It is an early-onset, lifelong condition, often being seen from around 6 months of age and cannot be cured; it can only be managed. 

The genetics of CDA

Dr Joanna Ilska (KC Genetics Health Manager) was the second speaker at the webinar and she discussed the research evidence and genetics of CDA. While the gene variants for dilution are now known and can be identified with DNA tests, the gene (or genes) that cause CDA have not been found, to date. Joanna explained that, while dilute colour is a predisposing factor for CDA in Dachshunds, the 2 traits are not irrevocably linked. The fact that dilute colours in some other breeds do not suffer from CDA and not all blue or isabella Dachshunds do either, shows this is not a simple genetic condition. The evidence also does not support the view that other health conditions are caused by the coat colour. So, the fact that many of the dilute dogs in our 2021 survey also suffered from autoimmune conditions is more likely to be a result of close inbreeding, use of popular sires, and strong selection within a narrow population pool.

The scientific evidence on the association between colour dilution and CDA was reviewed by the veterinary and genetics specialists on the KC’s Genetics & Health Screening Dog Health Group and they recommended an educational approach rather than a ban on registration of dilute Dachshunds. This webinar was part of that educational approach. 

Recognising that where there is demand, there will be supply, Joanna stressed the dangers of breeding for “rare” colours and offered some practical advice to minimise the risks. This included carrying out all recommended health screening, breeding from dogs over the age of 2 once they were known to be unaffected by CDA, and avoiding close inbreeding and popular sires.

Discouraging “rare” colours

You may have read the recent press release on the recommendations from the NBS Colour Working Party. The Colour Watch system mentioned in their report will be one element of the KC’s approach and provides a framework for marketing and communication to puppy buyers, breeders and owners. Work is also underway as part of the KC’s strategic review to establish more effective ways within the registration system to promote well-bred puppies with breed standard colours and relevant health-tests. For several breeds, there have also been changes made to Breed Standards and to the lists of BS and NBS colours in the registration process.

How to raise awareness?

The Colour Watch system will be a key element in the KC’s approach to raising awareness of the risks of breeding for so-called rare colours and NBS colours. Several breed club communities are already producing educational materials and we have seen great examples of these at Discover Dogs and on club websites. Clearly, there is a role for breed clubs and councils, as well as the KC. 

The KC would, of course, be pleased to collaborate with breed clubs and their charities on joint campaigns that help raise awareness. One simple step would be for breed clubs to share links to this webinar and the other resources in the KC Health YouTube channel. If breed clubs are serious about protecting the health of their breed, they need to be proactive on social media. On Facebook, there are dozens of Dachshund Facebook Groups and it’s likely the same for other breeds. It is a massive task, though, and we need to address both supply and demand.

‘The greatest enemy of knowledge is not ignorance, it’s the illusion of knowledge’: Stephen Hawking 

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Who’s looking at the bigger picture?

It’s very easy to get so focused on what’s going on in your own breed (or breeds) that you lose sight of the bigger picture and wider context of what’s happening in the world of dogs. For some breeds, particularly the brachycephalics, there has been a huge amount of scrutiny for many years. The most proactive breed clubs and Breed Health Coordinators have focused on getting messages across about good breeding practices and the value of health screening programmes. Some, though, are less proactive and are perhaps wondering what new legislation is going to hit them. If their short-term focus is on tinkering with their Breed Standard or uptake of a single-gene DNA “health” test, I suspect they will be in for either a disappointment or a shock. While it may be true that “backyard breeders” are the cause of many health issues through poor breeding practices and a disregard for the Breed Standard, it’s likely that those in breed club communities will be impacted first. Breed club communities and those who show their dogs are an easily identifiable target for criticism.

At a National level, Kennel Clubs have to juggle and balance priorities across multiple breeds. Decisions that are made for one breed can often have wider implications across other breeds. Here in the UK, there was a time when the KC would consider implementing “Control Schemes” in specific breeds. Probably the best-known example is CLAD testing in Irish Setters.

With effect from 1 July 2005, the Kennel Club would only register Irish Setters that are proven to be clear of CLAD, or hereditarily clear of CLAD e.g. both parents are clear. With effect from 1 January 2008, the Kennel Club ceased to accept any registrations for Irish Setters produced from a CLAD carrier parent mated to a clear or hereditarily clear parent. Breeders wishing to register progeny from a carrier after this date were required to apply for permission prior to the proposed mating, and applications are dealt with on a case-by-case basis.

Hindsight is a wonderful thing

I remember going to a meeting more than 20 years ago with Professor Jeff Sampson (the KC’s geneticist at the time) where we asked if a control scheme could be introduced for Miniature Dachshunds so that cord1 PRA could be eradicated from the breed. Thankfully, in hindsight, Jeff argued that this would not be in the best interests of the breed and could actually make things worse by further reducing genetic diversity. We had similar discussions with the KC about banning registrations of Mini Wires that were affected by Lafora Disease or that were untested. Hindsight is a wonderful thing and we now know that early onset PRA in Miniature Dachshunds is not caused solely by the cord1 mutation. We have also been able to reduce the risks of breeding Lafora-affected puppies without having the constraints of a Control Scheme.

These days, the KC’s health and genetics advisors are very much aware of the challenges associated with loss of genetic diversity and, I believe, the current policy is that Control Schemes are not considered to be an effective tool for managing inherited diseases. This is a good example of how the role of the KC is to understand the bigger picture and to educate breed clubs and breeders on the potential adverse consequences of what might seem like “simple” solutions.

The KC policy that puppies from merle-to-merle matings cannot be registered is another example of where seeing the bigger picture can (and should) influence a decision. The number of merle-to-merle matings was always very low and the risks of breeding health-compromised puppies was known to be high. As such, this decision made sense across multiple breeds where the merle gene is present. The impact of this policy on genetic diversity is low but the impact on avoiding significant health risks is high.

Unintended consequences

I’m sure there are plenty of other examples where breed clubs might argue for registrations to be restricted on the basis of health tests or where they believe there are health issues associated with particular aspects of the Breed Standard (e.g. conformation or colour). Stepping back and considering the bigger picture and potential undesirable consequences might lead us to alternative approaches. For example, if people can’t register with the KC, will these dogs continue to be bred outside the KC system or will their breeders register them with false details? In the former case, we still end up with unhealthy dogs that may suffer from lifelong illnesses and, in the latter case, we end up with a KC registry based on unreliable information. The KC might also have to consider whether a decision that apparently makes sense in one breed would have knock-on effects if applied to other breeds.

At an international level, the challenges of joining the dots and making sense of varying KC policies and diverse national legislation are even greater. Our KC has reciprocal agreements with many other KCs and the FCI acts as a worldwide body for 98 members and contract partners, with oversight of 355 breeds.

What is truly in the best interest of all dogs?

The International Partnership for Dogs is another organisation taking a broader perspective on the world of dogs. They have recently published their Annual Report for 2021. In her opening remarks, Acting CEO Katariina Mäki says “we continue to work with our stakeholders to educate our global community and promote what is truly in the best interest of all dogs”. She also says “We need collaboration among our stakeholders now more than ever”. That group of stakeholders includes KCs, groups with breed-specific interests, academics/researchers and members of the pet industry, including DNA test providers. Their Harmonization of Genetic Testing for Dogs Database now includes 82 academic and commercial Genetic Test Providers (GTPs) in 22 countries. IPFD’s online platform dogwellnet.com is their main channel for connecting with the dog community and, if you haven’t already done so, I’d recommend joining the 2000+ people who have signed-up for a free account which will give you access to all of their resources. If you’re a breeder or breed club officer, the information and tools available for 182 breeds are immensely valuable. Over the past couple of years, IPFD has put a lot of effort into creating over 1000 Breed Relevance Ratings for the list of nearly 2000 breed-specific DNA tests that are available. These evidence-based ratings, together with Globally Relevant Integrated Health Profiles (GRIHP) describe the big picture of health on conditions of interest within a specific breed.

Next month, IPFD will be running their second Virtual Dog Health Workshop with a focus on Genetic Diversity. I’ve been invited to attend, so I expect there will be plenty to share in future “Best of Health” articles.

We’ll only make progress by working together

I was invited to speak at the 2021 British Veterinary Orthopaedic Association (BVOA) conference and did so on November 19th. When I accepted the invitation in July, it seemed a long way off and my brief was to give a give a breed club perspective of canine health. This was a 3-day conference and was face-to-face, having not been able to run in 2020. 

The conference was fully booked with around 130 delegates and, apparently, they had to turn away 40 people simply because the venue was full at 130. When I arrived, I realised that I was probably the only person there who didn’t have a veterinary qualification. A few delegates put me right on that by saying these weren’t just vets, they were orthopaedic vets. I’m not quite sure how different that made this audience or whether a group of cardiologists would also have been rather different! Whatever, I didn’t get much sleep the night before my presentation, wondering quite how it would go down with this audience.

To make things even more challenging, my presentation followed one from Dr Dan O’Neill (Royal Veterinary College) who runs the VetCompass project. Dan’s an epidemiologist and anyone who has heard him speak will know how engaging and interesting he is to listen to.

I had spoken with a few of the delegates about their knowledge of the Kennel Club and Breed Clubs and it was pretty clear that most people would probably know very little about the role of these in improving the health of pedigree dogs. To that extent, I had a blank canvas to work with.

I don’t like making presentations that are simply a one-way download of content from a set of slides and my (early morning) session needed to generate some discussion for the Q&A panel later in the morning. I started by asking if there were any Dachshund owners in the room and just one hand went up. Asking about whether any of them had been presented with a Dachshund at their surgery in the past 2 weeks raised about 10% of hands. Surprisingly, when I asked if any of them were aware of the Kennel Club’s Dachshund IVDD screening programme (which only launched in May this year), many more hands went up. That was great to see and my talk would be followed by Dr Mark Lowrie who is one of the IVDD programme scrutineers, so we’d have 100% awareness by the end of the morning.

The UK canine landscape

I began my presentation by discussing the UK canine landscape and where the KC sits within that. Depending on whose estimate you go with, there are about 9-10 million dogs in the UK. The KC registers about 250,000 p.a. So that probably means there are 3 million KC registered pedigree dogs living in the UK. Estimates also suggest there’s a similar number of non-registered pedigree dogs. These are bred and owned outside the KC system, with no involvement in KC-regulated activities. The balance are crossbreeds (known to be growing in popularity) and mongrels. Despite what we might think about the importance of the show world, size-wise, it involves just a tiny fraction of UK dog owners, maybe 0.3% of owners.

We’ve all probably got tired of hearing the phrase “following the science” over the past 2 years but it’s highly relevant to the way the KC addresses health matters. I described the role of the Dog Health Group in setting overall strategy and its 4 subgroups that contribute specific expertise on aspects of canine genetics, epidemiology, health screening, health and welfare.

The role of Breed Clubs is more complicated and quite variable from breed to breed but there are recurring themes of activities the more proactive clubs get involved with. I was able to use the KC’s Health Strategy toolkit to illustrate the many things a “good” breed would be doing. 

The most practical demonstration of KC and Breed Club focus on health improvement is the development of Breed Health and Conservation Plans. Well over 100 BHCPs are now in place and these cover around 80% of KC breed registrations. I’ve written about the value of these before so I won’t cover that ground again but my point to the veterinary audience was that these are developed collaboratively by the KC and breed clubs in order to provide a single source of up-to-date evidence and plans for each breed. In the case of Dachshunds, we have taken the BHCP and customised it for a veterinary audience, highlighting the priority conditions and screening programmes we think vets should be aware of.

Diverse voices and polarised opinions

Of course, it’s important to recognise that there are many different views on canine health, particularly in relation to the role of Kennel Clubs, Breed Clubs and the show community. There are diverse voices and polarised opinions from many different interest groups, vets being just one.

On the first day of the conference there were presentations where comments were made about “couch potato” Labradors and they were contrasted with those used for working activities. It’s very easy for extreme examples of any pedigree breed to be used to condemn the whole of a breed and breeders. During the panel discussion in which I participated, I took the opportunity to explain the role of the KC’s Breed Standards and Conformation Group in collecting feedback from judges on visible points of concern (Breed Watch) and how Breed Standards are regularly reviewed.

During my talk, I touched on the topic of Human Behaviour Change and emphasised that it’s not just breeders and exhibitors whose behaviour might need to change, but also that of puppy buyers and vets. I used a couple of examples of what we have achieved in Dachshunds to illustrate how a systematic approach to health improvement, with appropriate human behaviour changes had delivered quantifiable benefits. The first example was how we have reduced the incidence of Lafora Disease in Miniature Wirehaired Dachshunds since 2012. That is an example where we have a DNA test for a simple recessive condition. The second example is the complex, multifactorial condition Intervertebral Disc Disease (IVDD). Here our improvement programme is based on a well-researched screening programme plus evidence on lifestyle factors that breeders, owners and vets can address to reduce IVDD risk.

I was pleased to get positive feedback on my presentation and I hope I helped raise awareness among this group of vets about how they can collaborate with the KC and breed club communities. I left them with a quote from astronaut Chris Hadfield: “You can’t change the bricks, and together, you still have to build a wall”. In other words, we are where we are but we’ll only make progress by working together.

Judging for health should not be controversial

A recent Our Dogs “Question Time” feature on vet checks at Championship shows for Best of Breed winners in Breed Watch Category 3 got me thinking about the role of judges in protecting breed health.

It’s hard to believe that it’s 9 years since vet checks were introduced at Crufts 2012 for what were then known as “high profile breeds”. The plan for these checks had been announced by the KC during 2011 but its significance had probably not been realised until the show in 2012. It’s worth recalling that these checks were introduced in the period following Pedigree Dogs Exposed and at a time when there were attempts to shame Crufts off our television screens completely. Pedigree dogs were in the spotlight and the KC was arguing that dog shows had the potential to be a force for good in demonstrating fit and healthy purebreds. Professor Patrick Bateson, in his 2010 report on pedigree dog breeding, had also referred to the influence of dog shows on dog welfare:

“I was persuaded that showing and judging constitute a powerful lever for change. That has been demonstrated clearly in the past in the documented and undisputed changes in form that have taken place in many breeds. My concern therefore is that this powerful lever should be effectively applied to achieve the desired improvements in welfare.” and…

Judging is not an exact science but it needs to be informed by recent advances in knowledge. It would be improved with a mechanism for re-training or updating judges over time (what in other circles would be termed continuing development). It would also be enhanced by the introduction of a mechanism for singling out judges who manifestly upheld welfare principles and kept themselves up-to-date.”

At the time, the vet checks were hugely controversial among the show community and made headlines because 6 of the 15 Crufts Best of Breeds failed the examination and were unable to enter their Group competitions. Social media responded with new groups set up in protest at the KC’s actions. That year’s KC AGM also had some heated discussion but a proposal to halt the vet checks was not supported.

The veterinary press, unsurprisingly, took a different perspective and were generally supportive of the vet check process. In a letter to the Vet Record, the 2 Crufts vets (Alison Skipper and Will Jeffels) wrote “The fact that the KC gave two ordinary general practitioners the authority to overrule the decisions of internationally famous judges at the world’s biggest dog show, and trusted us to make impartial decisions about the dogs we examined, is a great mark of confidence in the integrity and ethics of our profession. We should not let them down. We very much hope that many other vets will support the KC by volunteering to carry out these checks at a championship show.”

In contrast, the following year all the high profile breeds passed their Crufts vet checks and proceeded to the group competitions. 

Breed Watch

The concept of high profile breeds has now been incorporated into the Breed Watch scheme with those breeds being in Category 3. The fact that there are now just 9 Category 3 breeds is a reflection of the progress made by those that have been moved to Category 2. Vet checks remain as a reminder to both judges and exhibitors that health points of concern that are visible to the lay-person should not be acceptable in the show-ring.

Whether vet checks should be extended to all breeds prior to group competition is debatable. Personally, I’d have no issue with it and, if the dogs are fit and healthy, judges and exhibitors should have nothing to fear. The logistics of it could, however, be quite challenging and with more vets involved they would clearly need to have been fully briefed on their role. On balance, I think vet checks are proportionate for Category 3 breeds. The onus is on those in Category 2 not to allow unhealthy exaggerations to creep in that would result in them being moved to Category 3.

Breed Watch health reporting for CC judges of Category 2 and 3 breeds is mandatory but voluntary for Category 1 breeds. Honest reporting of any concerns can only be beneficial if we are serious about shows being a showcase for healthy pedigree dogs.

The tail wagging the dog?

It’s also easy to argue that judges and vets completing visual assessments at Championship shows is the “tail wagging the dog”. If the first time that a judge has to make any comment on the health of a dog they are assessing is when they first award Challenge Certificates, then we’ve missed a huge part of their apprenticeship. First time CC judges will have spent a minimum of 7 years on their journey of education, mentoring and hands-on judging. Awareness of health matters should be baked into that process. How many people realise that Breed Watch is embedded into the introductory section of every Breed Standard?

“Breeders and judges should at all times be careful to avoid obvious conditions or exaggerations which would be detrimental in any way to the health, welfare or soundness of this breed. From time to time certain conditions or exaggerations may be considered to have the potential to affect dogs in some breeds adversely, and judges and breeders are requested to refer to the Breed Watch section of the Kennel Club website here https://www.thekennelclub.org.uk/events-and-activities/dog-showing/judging-dog-shows/breed-watch/ for details of any such current issues.”

As such, aspiring judges should be learning about Breed Watch and how its principles are meant to be applied, throughout their education. I wonder how much time is spent at Breed Appreciation Days discussing how to assess for visible health concerns compared with how to assess length of ribbing or turn of stifle. Similarly, how many mentoring sessions involve a discussion of visible points of concern as well as discussing dogs’ hind angulation? It really shouldn’t be too much of a stretch to do this because, in some breeds, the visible points of concern are closely aligned to faulty construction or movement. Surely we should be encouraging education and assessment of Breed Watch aspects throughout a judge’s career.

I have to declare an interest as I am a member of the KC’s Breed Standards and Conformation Group (BSCG), a subgroup of the Dog Health Group. The BSCG sets policy for Breed Watch and reviews the reports submitted by judges. Opinions expressed here are my own and not those of the BSCG.

An insight into brachycephalic dog health from The Kennel Club

The Kennel Club has hosted a unique webcast to discuss brachycephalic health and what can be done collaboratively to ensure a healthier future for dogs. Chaired by Kennel Club Chairman, Tony Allcock OBE, the webcast panel comprised Dr Jane Ladlow, European and Royal College Specialist in Small Animal Surgery and leading BOAS researcher; Bill Lambert, Head of Health and Welfare at the Kennel Club; and Charlotte McNamara, Health and Welfare Development Manager at the Kennel Club.

The panel discussed brachycephalic health, approaches across Europe, the need for a collaborative, evidence-based approach, including how the Respiratory Function Grading Scheme can help protect and improve the health of brachycephalic dogs now and in the future, and the importance of data collection and ongoing research into the complex Brachycephalic Obstructive Airways Syndrome (BOAS).

Further information about brachycephalic dog health, what the Kennel Club is doing and which tools and health screening is available to breeders can be found at: https://www.thekennelclub.org.uk/flatfaceddoghealth

To donate and support further research into brachycephalic dog health and BOAS, visit: https://uk.virginmoneygiving.com/charity-web/charity/displayCharityCampaignPage.action?charityCampaignUrl=BDH