Breed Health Information and Update

This article was originally written for the December 2021 club magazine but here on the web site has been slightly modified to summarise the ongoing current Bernese Health Situation. Following lockdown it was great to get back into the real world, meet people and have proper discussions and answer queries. Some of the queries made me realise that not everyone is completely au fait with all aspects of the various Bernese health processes, there are lots of new members and owners so I decided to do a quick summary of some of them. A sort of quick guide to Bernese Health for Beginners but also with some some thoughts, as BHC, of how I see future health testing developing.

Whether you are new or a long established owner please make sure you at least check out the last section “Other health related initiatives….. ” for how YOU can help our breed today. As always more details can be found at www.bernese.co.uk/health and indeed some parts of this article have been taken from our web site.

Bernese Health Initiative

The 2021 AutumnGarden Party week-end saw the debut of the Bernese Health Initiative stall. As you may have read in the 2021 club handbook the BHI was launched during the lockdown period to give some focus and a more collaborative approach to all health issues.  The BHI has its own logo and currently consists of myself as Breed Health CoOrdinator, Emily Green and Donna Hughes, both also on the main club committee. We manage the club’s Health fund reporting back to the committee and organise all health initiatives and fund raising activities and, as we go forward, subsequent spending. Emily was the main creator of the new stall which proved such a great focal point at the September events having a selection of exclusive quality items for sale, some made by Donna, and was the location of the ‘Histio testing’, of which more later. It also served as a centre for breed health information and queries and we explained the ‘Histio test’ and demonstrated its application numerous times over the week-ends. The stall was also the location of the Histio blood testing organised by the BHI and provided by Dr Rich Irvine. All of which is exactly why we were there, so it was great to experience, and be able to respond to, some fresh interest in BMD health.

If ever you wish to donate anything to Bernese Health, items for raffles, auctions or even monies please email us on bhi@bernese.co.ukLikewise if you have any specific health related query feel free to contact us on the same address or myself individually on health@bernese.co.uk

BHI Members Donna Hughes, Emily Green and Steve Green plus Dr Rich Irvine at the BHI stall at the 2021 Championship Show

Breed Health and Conservation Plan (BHCP)

Hips, Elbows, ‘Histio’, DM and CoI, as outlined below, are the five main thrusts of breed health that were contained in the BHCP introduced for our breed by the Kennel Club in 2018. Our club supports this plan and incorporated its recommendations into our Code of Ethics in the same year. Other BMD clubs have so far been slower to respond but if a majority do so the KC will incorporate more of the plan into general and Assured Breeder Scheme recommendations for our breed.

 

BVA/KC Hip and Elbow Scoring

To get straight to the basic rationale, like many breeds Bernese have an identified potential problem with Hip Dysplasia (HD) and Elbow Dysplasia (ED). This does not mean we have to worry about all Bernese having problems in these areas but that sensible precautions should be taken both in management and breeding choices to minimise the chances of these conditions occurring. Elbows in particular were a problem for our breed and we were the pioneers of the UK elbow scoring scheme before it was adapted and rolled out to all of dogdom in the 1990s.

Although not a simple recessive gene mode of inheritance, both of these conditions are known to have a causative hereditary element to their occurrence so by assessing potential parents prior to breeding the better specimens can be selected and the frequency and severity of HD and ED can be reduced and minimised. This involves X-raying all breeding stock and assessing the results under a consistent scheme in order to select the better ones for breeding. For all responsible breeders Hip and Elbow scoring of BOTH parents has become extremely routine in the UK, and most other countries. The UK Hip scoring scheme has been around in it’s current form since the early eighties and the Elbow scoring scheme was introduced in the late nineties although it took a few years for it to settle into it’s exact current format. The vast majority of dogs have their elbows X rayed for scoring at the same time as their hips, which has the obvious advantage of only requiring one anaesthetic process to be administered, and can be done anytime after the dog has reached 12 months of age.

The long time established schemes mean it is not unreasonable nowadays to expect all potential puppies, whatever country they are born in, to have hip and elbow scored parents and grand-parents and if either of the parents of any prospective puppy are not scored then you really should ask why and almost certainly walk away. However, note that some dogs may not have UK hip or elbow scores but will have been scored overseas and thus not show on the British KC system.

 

UK Hip Scoring in brief

Put simply hips are split into 9 categories which are assessed by a specialist panel at the BVA (British Veterinary Association) from a single X ray of the dog’s hips taken after the age of 12 months. Some of these categories relate to the correct formation and development of both the femoral heads and the pelvic sockets including the presence of the early signs of arthritis caused by undue stress to the bone, and other categories are concerned with the correctness of the fit of this ball and socket joint. All of the categories are scored for each hip and the scores added up. Each of the categories is scored 0 to 6, except one which is 0 to 5, so the maximum score per hip is 53 and the absolute highest score possible is 53 right and 53 left giving a total of 106. As the scores reflect negative features and the amount they deviate from a perfect healthy hip the highest scores indicate the worst hips, so a 53:53= 106 would be the absolute worst case scenario and a 0:0 the perfect score.

For many years after the introduction of this scheme our breed average score was fairly settled at about 15 or 16, but in more recent years due to the positive effects of people scoring and taking heed of the scores plus the stated breed average being amended by the KC to reflect just the last five years rolling average of scoring, the figure has dropped to around 11 but seems to be settled at that level.

 

 UK Elbow Scoring in brief

The elbow scoring in the UK system is essentially very similar to that used in many other places in the world. Elbows are X-rayed and then graded for the amount of pre-arthritis bone growth that can be seen around the joint. Even in young dogs this growth can be used to assess the potential issues the dog will face later in life. Just like the FCI system a grade is given for each elbow and the overall grade is determined by the higher of the two individual grades. The 4 possible grades are:

  • 0 = Radiographically normal (no arthritic changes seen)
  • 1 = Mild osteoarthritis
  • 2 = Moderate osteoarthritis or a primary lesion with no osteoarthritis
  • 3 = Severe osteoarthritis or primary lesion with osteoarthritis

As an example, a dog scoring 0 on the left and 2 on the right would simply be graded as a ‘2 elbow score’.

 

EBVs – In more recent years the KC have developed EBVs, Estimated Breeding Values, for Hips and Elbows for our breed. Whilst it is generally the case, good individual scores in parents are not an absolute guarantee of good scores in offspring as anomalies can occur but EBVs, in some ways, should be more reliable.

EBVs give a risk estimate for the hips or elbows for any particular dog and this differs from the individual score because it also takes into account the influence of scored relatives of that dog. Parents and closer relatives will be given more influence than more distant ones but overall a rating can be given taking influence from every related scored dog.

Whilst great in principle and generally supporting the sensible thinking of well informed breeders there are a couple of big caveats with EBVs is the relatively low number of siblings and antecedents who will be scored. Whilst most dogs used for breeding and therefore shown on pedigrees will be scored there are a massive amount of dogs as siblings and cousins to all the dogs on the pedigree who will never be scored but in an ideal world would have a great deal of information to give about their lines. Also using the KC database, whenever, it is returned to full functionality, dogs scored overseas are not taken into consideration either so their scores, good or bad, do not influence the KC calculation. So, the effectiveness of EBVs is diminished BUT they can still give a broader picture of the situation with any particular dog than just looking at direct parents, grandparents etc so are always worth including in considerations to at least some degree.

Due to the ongoing issues with the KC web site I do not propose to delve into EBVs any further here as they are not yet fully available to us, only hips, whilst the KC continue to sort out their technical issues.

 

Histio Testing

‘Histio’ is the most common term used globally within the breed to refer to the disease which officially has several different names Systemic Histiocytosis, (SH) and Histiocytic Sarcoma (HS) being the main ones nowadays with the original Malignant Histiocytosis (MH) being much less heard. These all, certainly as far as our breed community is concerned, are the same condition which is a very aggressive cancer type disease manifesting typically, but not exclusively, in middle age Bernese say 4-6 years old and always resulting in a fairly swift decline and death. The speed of this decline varying from just a few days from first noticing symptoms to a couple of months at best. Experts I have spoken to have said that if your Bernese goes much longer than this then the diagnosis is perhaps not correct.

Diagnosis is a problematic point with this disease as there is not yet, a definitive test to prove it is present. It can manifest in different locations in the body but most typically, again not exclusively, it will affect the organs of the upper torso, lungs, heart, liver, spleen and heart. Dogs will often present with a general malaise, poor appetite, lethargy and often severe anaemia showing as very pale gums. Further investigation, typically a few days down the line and after trying antibiotics, anti-inflammatories or steroid based treatment will reveal ‘shadows’ on X ray, for example on the lungs.  The only certain diagnosis is from a tumour sample which is not common because dogs deteriorate so quickly. It is rapidly apparent there is only going to be one ending whatever is done and the dog is clearly too weak for a major operation to access the relevant organs. Due to this several experts I have spoken with have said that ‘Histio’ just has to be underdiagnosed but even so around a quarter of our breed are reported as dying due to Histio and this is part of the two thirds that die due to cancer.

Following research and experience in many countries, but led by the USA and particularly France, it was proven that there is a hereditary aspect to the occurrence of ‘Histio’ and the search for the implicated genes eventually saw the introduction of a revolutionary new type of genetic test.  Taken from a blood sample, this test looks at 9 different areas of the genome to give a risk factor for each dog tested and grade them all A, B or C. Even better, a database followed, Histiocytic Sarcoma Index Mating Selection or HSIMS, which allows specific individual potential matings to be assessed to give an exact prediction of the percentage of Index A, Index B and Index C dogs that will be produced by that mating.

Proper widespread use of this test will help to gradually reduce the incidence of ‘Histio’ in our breed. Support has been slow to come in many areas and some breeders remain sceptical and have not fully embraced the test. However, engagement is gradually growing and recent reduced fee blood testing offered at our September events was, whilst not at the ‘all day queuing levels I have seen overseas, quite well supported. It remains a fact that we will not improve the impact of this disease on our breed until all breeders accept it is a real problem with a hereditary factor and start to deal with it instead of treating cancer as simply ‘bad luck’ that keeps on happening.

 

Degenerative Myelopathy (DM)

This is a condition found in numerous breeds although we do have our own extra slant on it. It is a degenerative disease of the nervous system, usually occurring from about 6 years of age onwards but sometimes earlier. It basically results in the dog losing the use of its rear feet, then legs and gradually this spreads to include bodily functions (e.g. double incontinence). This can take place of several years or a shorter time but the disease progresses through to the inevitable conclusion. Fortunately there is a straightforward genetic test widely available which give definitive results and indicates that a dog is clear, a carrier or affected or as we usually say in our breed ‘at risk’ of developing the disease. As long as any mating has one clear dog involved, mother or father, none of the puppies will be in the ‘at risk’ category. Therefore the disease should be entirely avoidable by breeding practice if all parents are tested.

Bernese have developed their own mutation of this disease in the same part of the genome and our stock needs to be ‘double clear’ to be full clear so one DM test is not enough our breed should be tested for both the SOD1A or Exon2 and the SOD1B or Exon1 mutations. One parent being clear by testing or parentage of BOTH of these mutations means none of their puppies will ever develop the disease.  It is not enough to be clear on only one test as the dog could still be a carrier or affected with the other mutation and cause the disease.

One point to make is that there are many similar conditions with very similar symptoms and just because you have a Bernese with some symptoms it is not a definite case of DM, and most times it is not. Unfortunately the only certain diagnosis is via an analysis of a cross section of the spine which can only be done after death so, as with Histio, there are difficulties ascertaining precise facts about this disease.

 

CoEfficient of Inbreeding (CoI)

This is a calculation that can be undertaken for any prospective mating where the pedigrees are known and is an expression of how closely bred the litter would be. Genetic diversity is increasingly understood to be a good factor in promoting healthy dogs and the KC have had a push on this in recent years. CoI was specifically mentioned in the 2018 revision of the Animal Welfare Act (AWA) which placed clear guidance on dog breeders to promote genetic diversity.

Being rather simplistic about it for the purposes of this article, generations of ‘line breeding’ mostly for all sorts of worthwhile reasons, has led to small gene pools in many breeds. Individuals may appear diverse on pedigrees but thorough population genetics, or more commonly nowadays modern clinical DNA analysis, can show whole breeds may have originated from a limited number of individuals who are actually behind all dogs if you go back far enough. I have been at several seminars where this has been raised and more than one expert has said that the only answer to the problem for many breeds will eventually be to outcross to another breed. As you can imagine this does not go down well with any breed enthusiasts so we have to try and address the issue ourselves to reduce the possibility in the future of enforced action or problems we really will not like.

The KC system can produce a CoI for any registered dog and the advice in the AWA said to stick to breed average or below. Our breed average is currently 3.4% which might seem a very low figure but it should perhaps be pointed out that the highest possible figure is 25% which would be for a brother/sister or father/daughter mating. It is widely accepted that the lower the CoI the less likely bad genetic influences will manifest so good genetic diversity can only improve the chances of a healthy dog in many areas.

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So, why can’t breeders just ‘do the right thing’ and simply eliminate or constantly reduce these diseases?

As already stated both HD and ED are polygenic diseases which means they do not have a simple straightforward cause and consequently it is impossible to exactly proportion causative factors when they do occur. Sooner or later, most breeders wil hexperience a case of ‘good’ to ‘good’ producing a bad outcome. Nature throws little bombs at us sometimes. In terms of how it can be applied to the breed ‘Histio’ could be said in some ways to have a similar, not specific, basis. DM is, genetically, much clearer and, whilst there is a feeling in some quarters of a further influence being involved to partly explain the low number of actual cases in our breed, DM is still a much clearer inheritance than Hips, Elbows and ‘Histio’. However, no one seriously argues that there is not a definite hereditary disposition component to any of these problems and the best way to reduce both the initial incidence of these diseases and, for hips and elbows at least, the severity of their symptoms as well, is by tackling this in sensible breeding choices. This is where the health schemes outlined above should apply to give breeders an idea of the risk of any particular dog or combination of parents passing on HD or ED or ‘Histio’ to its offspring.

However, it is not as simple as using low scored dogs and ignoring all other factors. In an ideal world we would all be able to always use dogs with lower scores than our own in all areas but in reality we are breeding complete Bernese Mountain Dogs, not just improving hips or just improving elbows or just reducing ‘Histio’ or just avoiding DM and or decreasing the CoI. Usually a degree of compromise in certain areas is required and this is where experience and knowledge come in and it can all become a matter of degree. We’d all like to improve in all areas in every mating but it is just not possible as the perfect stud dog does not exist and breeding is all about making informed judgements and then taking responsibility for them.

UK BMD breeders voluntarily utilise health information and there are no set boundaries they must adhere to. Where clubs do have recommendations they are not binding and the ‘mandatory versus recommended’ testing practise debate has been heard at AGMs many times in many contexts over the decades and ‘voluntary’ (I think) has nearly always won over any ‘compulsory’ requirement. Some purists say there should be fixed boundaries, for example do not breed with a 25+ hip scored dog and in an ideal world this would of course be great if it were practicable but if the recommended ‘best practise’ in all these five areas was adhered to our breed would be effectively wiped out in a generation.

An exaggeration?? You’d perhaps think so but just consider about things as I put them below. Before you do though some of these figures are impossible to calculate so I have had to estimate them but they should be in the ball park of the true figures. It is also possible to apply them to the breed in different ways but I am only using them to make a general point not claim an verifiable exact figure at the end of it.

Hips – BVA advice is to only breed with breed average or better – so the official advice means 50% of the breed eliminated from the breeding programme so 50% available.

Elbows – BVA advice is to only breed with 0 scores, or 1 scores if we must. 87% of our scored dogs are 0 or 1 – so 13% of the breed would be eliminated and 87% available

Histio – A ratio cannot be applied and the point of the scheme is that all dogs are useable with due care but just to put a figure on it using the original, pre database, advice for the scheme as an estimate of not using C to C and C being 56% of the original tested UK population – so allowing for only one half of the mating say about 28% of the breed eliminated as not suitable for each mating if you were thinking of it in this wayso 72% available.

DM – General advice, including our club recommendation, says to ensure a double clear is on one side of the mating, again no exact figures exist but completely anecdotally I’d say about 95% of the tests I know about for SOD1B are clear and perhaps, being generous I think, about 50% for SOD1A are clear. – say about….

Exon 1 – 5% of the breed eliminated but only on one half of the mating so say 2.5% eliminated and 97.5% can be used

Exon 2 – 50% of the breed eliminated but only on one half of the mating so say 25% not useable and 75% available

CoI – Like hips, sticking to below breed average as recommended in the AWA 2018 means – 50% of the breed would be eliminated and 50% free to use.

So, multiplying together the above availability rates for the five health issues, i.e. 50% X 87% X 72% X 97.5% X 75% X 50%, by rigidly applying all the official advice being given you are left with around just 11% of the breed available for breeding. If a breeder tried 100% to do ALL the right things they could only have little more than a tenth of the breed to utilise in breeding. Theoretically applying this to ensure all the above factors are addressed would immediately make CoI impossible to comply with so our breed would be extinct in one generation if all the criteria were addressed in every mating.

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!!!Wow, Can this be right?

When I first considered this calculation I was surprised so I played with the numbers and worked it out again and then checked with a few people, including, most significantly, the KC geneticist, to be sure my reasoning was sound. He said that whilst he generally agreed with me, some of the numbers and the exact way I was applying them could be debated and some could go higher or even lower, but essentially my general point was correct. So, whilst the figures or exactly how they are applied, can be amended to give slightly different results the overall principle should not be lost by debating the detail. There is a much bigger discussion to be had about this principle as we accelerate into the age of increasing genetic testing for multiple conditions, across all breeds, but we should not enter this era with our eyes closed or anticipating it as a genetic utopia and expecting massive improvements. Even if all our ailments become ‘testable’ this raises its own set of issues which we have to be aware of and manage everyone’s expectations from future owners to regulatory bodies. Even the most ethical and responsible breeding will never be manufacturing in the engineering sense. There will always be decisions and compromises to make for breeders, the trick is to make thee decision from an as informed as possible position.

However, before some people develop the thought, this absolutely does not mean the health schemes are not worth supporting but exactly the opposite. Breeders simply cannot fix everything so should be aware of all the factors that they can be and concentrate on the areas they really need to with a good awareness of where they can and cannot compromise for their own dogs. Every mating is different and will have a different combination of factors. Know all the information there is to know about your dogs and then make evidenced and balanced decisions for the right and justifiable reasons. No breeder will ever be taken to court because a dog did not become a Champion but could potentially be taken to court due to any one of a multitude of health reasons when measurable hereditary factors are involved in that disease occurring and the breeder could be in difficulty if they cannot demonstrate ‘due diligence’.

It is also true that introducing fixed boundaries in certain measurable areas inevitably gives additional emphasis and importance to those areas and over a period of time this will ultimately be at the expense of other less measurable but highly important traits we will not give due attention to.

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Reality is EVEN MORE complicated than even this!

The essential last point I have to make in this area is that in terms of real life breeding I have so far only talked here about just 5 breed health factors. Things would be difficult enough considering these on their own but of course breeders have to consider many more things, maybe other health issues but clearly all the more obvious traits such as type, temperament, confirmation, markings, movement etc have to have a serious seat at the decision making table. If we take the official advice rigidly we would only have around 11% of the breed left to select from before we even start looking at the ‘traditional’ important areas!

Widespread testing and selective emphasis of areas with sensible use of the results individually has to be the way forward with breeders free to make their own decisions to improve matters for their own lines and therefore the breed. However, with that freedom comes responsibility and acceptance there is always a risk and being happy to explain this to puppy buyers and subsequently take ownership when things do go wrong, as they can for everyone at some point. By testing all areas breeders can assess the risks properly and make informed decisions.

 

Other Health related initiatives for ALL BERNESE OWNERS to help with

Aside from the schemes above there are three health related schemes that everyone with a Bernese can and, I would say, should get involved in when they can and this is a plea to do so if you are a Bernese owner. When ‘you can’ for the third of these is NOW.

Breed Death Survey – This is the ongoing Bernese Death Survey looking for simple information about the causes of death in our breed. This is essential as a starting point for research and understanding and is routinely undertaken in many countries. All Bernese deaths are important, even if the cause is not known for sure, so if, or rather unavoidably when, you experience the death of a Bernese PLEASE, PLEASE, PLEASE forward the details to the BMD Breed Death survey when you feel able to do so. The easiest way to do so for most people is online via the club web site and health section.

If you have not reported your Bernese deaths in the past you can still do so retrospectively and we welcome any Bernese details people can offer as owners or breeders however long ago the deaths were. No one else need know your details have been submitted and only summary details will be published in club publications or on our web site.

Veterans List – As a celebration of our older Bernese this ongoing list also sits within the health section of the web site and can be submitted online. Lists are sometimes published in hard copy and can be found on our web site. If you have a Bernese over 8 years please share the good news with our wider community.

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Summary

I hope I have explained the important health issues for our breed but also explained why things are not at all easy for the most conscientious of breeders and cannot be simply improved in the way some people feel they can.  Anyone looking to buy a puppy should ask about health issues alongside all the other questions they will have and if anything doesn’t make sense and the breeder cannot satisfactorily explain things then go away and take more advice before committing. Good breeders will understand and facilitate this.

Everyone with an interest in the Bernese Mountain Dog whether breeder, owner or even serious breed enquirer has a role to play in our breed’s health so the question to ask yourself, as a BMD person reading this magazine, is, are you doing what you can do to support the improvement of our breed’s health? Please, at least contribute to the Death Survey if you haven’t already?

Thank you.