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Pinky
22nd July 2008, 09:55 AM
I just wanted to get some views on this. I was talking to a breeder who owns a well known show dog. When I asked him about SM he explained that to get an MRI done in Ireland it costs in the region of €1200+ and the test itself is inconclusive. Even if the dog is clear on the scan it can still be a carrier of SM and pass it on to the pups. Any thoughts on this?

pcfarrar
22nd July 2008, 10:38 AM
Our last cavalier had an MRI scan done and it cost a few hundred pounds. But I think this was a special subsidised rate. I also believe you can get an inexpensive DNA test now.

Alison_Leighfield
22nd July 2008, 11:08 AM
The MRI done on that day is for that dog alone. It will tell you if that dog is clear of SM on that day. Dogs can also progress and develop SM at a much later age, a bouncy fit puppy and a young playful dog might not always stay that way as SM is a progresive disease and onset age is varied, so try not to assume that a dog will remain clear for its whole lifetime. There are recommended ages for scanning that breeders follow so that they can try to find their affected stock and withdraw them from any breeding.
How old is this dog in question? and do you know of any family history? is there clear around him? has he produced any clear scanned pups yet? go back and ask all this if you can, his answers will be interesting.
That dog may well produce affected even if clear itself, thats why it is so important to breed from MRI'd clear scanned dogs and bitches to see if this breeding does indeed make a difference to future generations of Cavaliers. Guess work is no good.

In my view it's a very poor excuse what he gave you, perhaps he simply doesn't want to know whats on the inside? If his dog was found to be affected then surely/hopefully that would end possible stud work as he shouldn't be bred from, and very possibly end his show career.

Hope some of this helps with your questions,

Alison.

Karlin
22nd July 2008, 11:35 AM
:xctly:

Consider that every indication is that this condition works in a way similar to MVD. Dogs that are heart clear and whose parents were heart clear til at least age 5 and completely fit with the MVD breeding protocol can still produce puppies with early onset MVD -- but the point is that it is *considerably less likely*.

No decent breeder would blindly breed cavaliers with no regard to the heart status of the parents, most importantly, but ideally knowing the lines as well. You do want to know that your breeding dog isn't the one unusual clear dog from a line with early ongoing heart problems.

Research in the Netherlands is showing pretty conclusively that clear dogs have other clear dogs around them in their immediate families. There's also a strong indication that affected dogs produce affected puppies whereas clear dogs produce clear puppies and mildly affected puppies.

With SM, believe me, breeders DO tend to know some of the dogs that have not scanned well and there are an increasing number of breeders who are making MRI info available on their lines and who are known for having dogs that have scanned well.

Anyone breeding in Ireland also should be aware that Geoff Skerritt at Chestergates Hospital in Chester will scan cavaliers for breeders in Cheshire for under €200 each. It is possible to take the early ferry, have the dogs scanned, and get the late afternoon ferry back. I had both my pet boys scanned in this way at my own expense and frankly, breeders complaining about costs in this way just don't cut it with me. The UK is full of very low cost schemes specifically for breeders and Irish breeders can use these too.

I suspect the more likely reason anyone has for avoiding scanning where these low cost schemes are easily available is not wanting to find their line is affected, and especially for stud dogs, this could seriously have an impact on the money the dog generates in stud fees.

Bet
22nd July 2008, 11:43 AM
May I chime in here .
It is known that A to A matings of MRI scanned Cavaliers have produced Off-springs with SM

I just dont know what the answer is .

NO-body seems to have definite proof that clear to clear MRI scanned Dogs will produce Puppies with no SM

At the moment .to help in this dilemma ,the Mode of Inheritance does'nt seem to be known
.
There is shortly to be guidance to be given to Breeders by Dr Sarah Blott ,who is Researching SM in Cavaliers at the Animal Health Trust ,in England ,for Breeders to have a Mating Program .

Bet

sins
22nd July 2008, 12:51 PM
Even if the dog is clear on the scan it can still be a carrier of SM and pass it on to the pups

I believe your breeder is being penny wise but pound foolish! If his dog was MRi scanned he would only lose the price of one pup at most, but actually gain in the long term by adding value to the rest of the dog's progeny if the scan came back clear.
Sins

Karlin
22nd July 2008, 01:05 PM
It is known that A to A matings of MRI scanned Cavaliers have produced Off-springs with SM

Bet, this point is noted by Alison and me :) but as also stated, this is very rare and in all the research studies so far, NO clear dogs have been produced in matings of dogs that were believed to be asymptomatic (and therefore assumed by their breeders to be clear but later scanned and found to have SM). Whereas clear dogs have produced almost no dogs with symptomatic SM and puppies on scans so far are either clear or have very mild status.

Inheritance is also not understood for MVD (sadly a situation set to continue as breeders refused to give enough heart info for the genome study for BOTH these conditions to have been analysed -- surely a crime in itself for the breed!!). Yet you yourself have argued strongly and passionately for years that dogs should be cardiac tested for the same reasons that people argue dogs need to be scanned -- every indication is the condition is strongly hereditary in the breed, the evidence is that breeding clearer dogs produces clearer offspring than breeding affected dogs, all else being equal. And there isn't a geneticist or researcher that believes the condition is not strongly hereditary, that I know of, in any country where research is being done -- dogs that are symptomatic tend to start to produce dogs that are also symtpomatic, as can be seen in several well known cases.

Given that breeders live with many dogs that many times are kept in kennels or separate dog quarters, the chance of observing symptoms also is low as many symptoms are not that pronounced until and unless the dog reaches severe status -- so I have no doubt that well intentioned breeders who do not scan are breeding symptomatic dogs that they think are not symptomatic. I have a deaf dog that came from a very health focused breeder who -- despite the fact that the dog was one of their personal favourites -- never realised she cannot hear. If this is the case with something as seemingly obvious as total deafness, I've no doubt it is very easy to miss the morning and nighttime scratching that is a common initial symptom, and may only happen after dogs are kennelled or off to the dog room, or before the breeder sees them in the morning. For example, I have absolutely no doubt my Leo would have been used at stud had I not bought him (this was the intention) because unless someone had him sleeping in the same room as themselves, they'd have missed all his growing symptoms between age 2-5, his prime breeding years, when he would scratch during the night or very first thing in the morning, never on walks though, no initial air scratching, no yelping, nothing.

I have spoken to Sarah Blott who definitely feels the condition is hereditary -- her goal is hopefully to discover the mechanism, eg to not understand IF but understand HOW. The problem is that breeders continue to not do scans, or work with her. More data is needed for her project to have any chance of success. Some actually feel there is already enough scan info out there to develop breeding recommendations based on DNA testing alone but the problem is that breeders have not submitted enough of the scan information that is already out there, and that is forcing breeders who do care, to continue to have to pay for scans.

Breeders and clubs could do much towards progressing research if there were some strong club and breeder support for the existing research programmes much less the work that will need to be done in future. I do know that several geneticists are not as hopeful as Sarah for the breed's future so really breeders should be fully backing her work as their best hope for having a breed to show in the years to come.

Karlin
22nd July 2008, 01:09 PM
This is what Sarah said in her presentation is Rugby (notes from Canadian CKCS Club):


SARAH BLOTT, B.Sc, M.Sc, Ph.D Department of Genetics, Centre for Preventive Medicine,
Animal Health Trust, Lanwades Park, Kentford, Newmarket, Suffolk, CB8 7UU

ìDr. Sarah Blott is a Research Group Leader at the Animal Health Trust (AHT) and is interested in the
development of breeding schemes for companion animals that combine state-of-the-art knowledge in
quantitative genetics with molecular genetic markers. She has a M.Sc. in Animal Breeding and a PhD in
Quantitative Genetics, completed at the Roslin Institute (Edinburgh).î

Highlights of presentation:
- Advises that presentation is to talk about ìhow to breed away from genetic diseases. Says that they
believe the disease (CM/SM) has a genetic basis.
- The 2 year Project is funded by the Kennel Club Charitable Trust (UK) and intend to look at 2 breeds;
the Labrador Retriever, because it has good hip dysplasia records and the Cavalier King Charles
Spaniel for Syringomyelia.
- Both are examples of complex diseases, are multifactorial and that we are not going to have a single
gene DNA test.
- Discusses persons she will be working with (Tom Lewis, a quantitative geneticist and Prof. John
Williams, a world expert in designing breeding schemes). Says they hope to come up with
recommendations and strategies to enable us to breed away from the disease (SM).


From: http://www.cavaliercanada.com/documents/VETERINARY_SATELLITE_MEETING_-_Website[1].pdf

Notes from the Rugby sessions. CDs are available of the actual talks themselves.

Margaret C
22nd July 2008, 01:51 PM
I think you should assume that every cavalier will probably carry one or more of the genes for SM, just as they will for MVD.
Puppies will get genes from both parents, some will be more lucky in the 'mix' they inherit than others, which is why you can get affected and 'clear' puppies in the same litter.
As Clare Rusbridge said in one of her earlier seminars, parents without early onset SM (two & a half years is the age that a cavalier is graded 'A' ) have more good genes to pass on than those affected at an early age.
No good breeder deliberately doubles up on faults.

I'm afraid this breeder is trotting out the standard excuses that are heard so often from those who fear what an MRI will show in their dog.
I presume that he would not mate together two cavaliers with early heart murmurs or slipping patella, but he is deliberately taking the risk of producing puppies that could have this really painful condition.

I have had so many phone calls from pet owners who have bought a cavalier from well-known show breeders & they have then spent months, sometimes years, trying to find out what is wrong with it.

There is a cavalier being shown, and winning well, that is limping and displaying obvious signs of discomfort in the ring. His owners say they want to make him into a champion & then they will put him in a pet home!
I hope they spell out to the new owner the prognosis for a dog with such early symptoms. There will be no chance of getting insurance.

It seems to me there is something very cynical & callous about campaigning a dog with obvious symptoms. The excitement and stress, together with the very long journeys, frequent bathing & almost continous brushing. A dog cannot say "please stop this is hurting" if the owners choose to ignore signs of SM
Where is there any consideration for the welfare of that dog?

Best wishes,

Margaret C

Pinky
22nd July 2008, 02:44 PM
Thanks for all the replies. The dogs he is breeding are over 3 so he said if they were symptomatic he wouldn't breed them full stop but I see Karlin's point about the possibility of missing the early signs of neck scratching. If I could find a breeder in Ireland who did MRI I would definitely get a puppy from them and wait as long as it takes as I do think it's important to support the breeders who are getting the MRI done but I am beginning to think they are non existent.

Bet
22nd July 2008, 04:14 PM
May I answer Margaret C
By saying that I think she is wrong in saying that it should be assumed that every Cavalier will carry one or more of the SM Genes.

In the recent CKCS UK Club News letter ,was an Article from Dr Sarah Blott which had been given at the CKCS Club Liason Meeting ,saying that there was concern that the estimates of Heritabilty may be Biased upwards,

This is because the Data has been Ascertained on the Basis of Clinical Cases

She also mentioned that among her next steps into SM in Cavaliers Research is to look at ways in which she can get a more Accurate or Unbiased Estimate of the Disease Incidence

I really think because of this comment that it can be assumed that every Cavalier will probably be carrying one or more of the SM Genes

Bet

Margaret C
22nd July 2008, 04:15 PM
Hello Pinky,

He is talking a lot of old tosh & he probably knows it.

Many cavaliers can have really bad SM but not show any signs until middle or old age. That is fortunate for them, but hard luck on any puppies they produce as they will pass on those faulty genes.
Only a MRI scan after the age of two & a half will show if a breeding cavalier can be considered an 'A' dog

In 1992, long before SM was recognised as a problem, I bred a champion stud dog who was eleven when he first showed obvious symptoms of SM. Unfortunately he was the father of hundreds of puppies by then, & many of them have subsequently shown up as SM affected.

Have you considered looking further afield?
There are people in the UK who are scanning their breeding stock. It would be hard to get a show potential cavalier but there are sometimes pet puppies, especially dog puppies available.
I'm always willing to help as much as possible if people email me.

Margaret C

Bet
22nd July 2008, 04:18 PM
IN my previous Post ,I should have added that it's .I believe wrong to assume every Cavalier will probably be carrying one or more of the SM Genes

Bet

Bet
22nd July 2008, 04:44 PM
Could I answer Karlin.
Yes I have argued for many years about the Heart Problem afflicting the Cavalier Breed.
I can make sense of Heart Testing Cavalier Breeding Stock before Mating ,but with SM there so many conflicting views, even for Breeders doing A to A there seems to be Puppies being born that can SM

Also why ,for me the big question is the reason for SM to be in other Small Breeds .

There's got to be a link it cant be Head Shapes,Those other Small Breeds have different Head Shapes and are of a different Sizes
so what is going on ,

Has any-body any thoughts about this.

I'll throw in a couple

Could it be ,for those Genetically Susceptible Dogs ,an Adverse Reaction from their Vaccinations ,

This could be a link for all the Small Breeds suffering from SM

Another thought mwhat about pesticides being Sprayed by Farmers onto Crops and getting into the Pet Food Chain .

last thought what about Laminated Floors and what they are being washed with

As the Song Says more questions than answers.

Maybe until all those avenues are explored ,then Breeders wont feel confident to MRI Scan ,especially when there are still Puppies coming from A to A matings

Bet

Bet
22nd July 2008, 07:16 PM
I have just read Margaret C's Post again

Is what is being said that if Cavaliers are being MRI Scanned and are Ato A matings and are over 2 and and a half ,then the Puppies wont have SM .

I just dont think that this can be claimed ,even if a only very few of the Pups go onto develope SM from Ato A matings ,then this just cant be the answer

I think more thought is needing to be being given about this advice

Hopefully Dr Blott's Breeding Program will be the way forward for Cavalier Breeders in fighting the SM Problem ,by trying to Breed it out of the Breed

Other ways have been tried but does'nt seem to have succeded especially with Ato A matings ,so fingers crossed ,Dr Blott's Program will succed

Bet

pcfarrar
22nd July 2008, 10:51 PM
Our last cavalier was totally free of malformations/syrinxes when he had his MRI at Chestergate. He was 9 years old and the specialist at the time said he was one of the best cavaliers he'd seen and gave him hope for the future of the breed. The specialist asked if he could use his scans in his lectures. He was a sanickro dog.

Karlin
23rd July 2008, 01:52 AM
Unfortunately Mr Skerritt has scanned fewer than 30 dogs out of nearly 700 that he considers clear of syrinxes and malformation. My Jaspar was another of these. Clear scans may however point to other dogs in the lines that are more likely to have good scans.


Maybe until all those avenues are explored ,then Breeders wont feel confident to MRI Scan ,especially when there are still Puppies coming from A to A matings

Bet

But why would they not scan, Bet? It is important to note that there have been almost no affected dogs from AxA matings -- I know of one, perhaps two, in two years, but this would be just as normal as seeing the occasional early onset MVD dog from parents with no murmurs -- the point is that you can significantly decrease the likelihood by not breeding affected parents. That has got to be much better than simply breeding blind and hoping the problem goes away, which seems to be the current approach for many people. Even if there is an environmental element, breeders still can only tell a dog's status by MRIing and there's very solid evidence that there's a strong genetic component that will be passed along by affected dogs. As with MVD, later onset SM tends to be far less severe for the dog. If the dog has a good scan at 2.5 that's a lot better than a dog riddled with syrinxes already at that age. If breeders won't scan because they think there may be an environmental factor, that's as poor an excuse as those who argue that they won't cardiologist test because they say they don't know where MVD really comes from and maybe it is to do with the environment. Very few reputable breeders however would not want to know the heart status of their breeding dogs, and I don't know anyone who would deliberately breed a dog with early onset MVD.

It may well be that affected numbers in the clinical samples are higher than would be seen in the general population -- but only scanning will show if that is the case to produce a random sample of sufficient size. I do think the French sample is very revealing though -- in that the French breeders put forward dogs for Laurent Cauzinille's small study with no symptoms that they all believed to be clear because they insisted SM was 'the British disease'.


In June 2006, the French club accepted his proposed study, which was small but with two key French breeders, conducted at the the Vet Imaging Centre in Paris.
* 16 dogs in the study
* all were clinically and neurologically ‘normal’ according to their breeders (who filled in a questionnaire) and verified by neurologist’s tests (but not MRI)
*all were LOF (French kennel club pedigree) and breeding dogs

Of the 16 dogs, 7 had SM and 1 had hydrocephalus “a big shock to the breeders” according to Cauzinille. All 16 had the malformation.

Sarah Blott does believe there is a very serious problem in cavaliers; this is why the breed was chosen for this study (which also includes hip dysplasia in labradors).

Pinky
23rd July 2008, 02:00 AM
Can CKCS be brought over to UK from Ireland for the reduced price MRI scan scheme or do you have to be an English citizen to benefit?

Karlin
23rd July 2008, 02:10 AM
I had mine done at Chestergates. Many of the schemes are designed more for breeders though and they are also intended to give grades for breeders but would not be for diagnosing a cavalier that needs treatment. I have a list of low cost clinics on www.smcavalier.com and the best thing to do for anyone interested is to contact the chosen clinic and see what their policy is.

Pinky
23rd July 2008, 02:13 AM
So it is pretty bad then for breeders in Ireland not to get this done if the low cost scheme applies to them too. There really is no excuse is there? Is it ok to add links here as I found some information on a possible connection between SM and Vaccines.

Karlin
23rd July 2008, 01:00 PM
Well there are numerous considerations for breeders and many reasons why they may or may not opt for doing scans, but in my opinion, it is sad that so few breeders in the UK or Ireland have done MRIs despite the availability of several low cost scanning programmes for several years now in the UK, and a couple of events organised by clubs (the first, by the Welsh club, could hardly get any participants) and therefore have no idea if they are breeding dogs that already have SM. Fortunately that has changed to some degree and clubs are getting greater enrollment for special scanning events, but information is still not being shared, not even with researchers like Sarah Blott who is trying to HELP breeders.

I find it hard to accept the argument of cost being prohibitive when as a pet owner, I was easily able to travel across on a ferry and get scans done in a day and cover that expense even though I am not on a large salary. Knowing leo's status helped me to be proactive in his treatment and early use of frusemide may well be why he has progressed only very slowly.

If I were breeding I could cover the cost of scanning several dogs with a single stud fee or a slight increase in the cost of puppies. But again, researchers have already stated a couple of times now that if only breeders who have already scanned would submit those results for research, it could well be possible to produce a guide for breeding based on incidence across certain lines and likely inheritance, meaning breeding dogs would not need to be scanned. Information submitted to Sarah Blott remains entirely confidential and her project is actually funded by the UK Club so breeders should feel comfortable working with her project. I hope more come forward to actively support this important work, which may well be the only realistic chance the breed has of survival.

The vaccine connection (to just about everything) is regularly brought up -- but the problem is that dogs worldwide are regularly vaccinated, and there is no indication anywhere that vaccines are causing such a huge problem according to every researcher -- or there would be equal rates of SM across numerous breeds, and it should affect large and small breeds. It has appeared in dogs that have not been vaccinated at all, where people have used homeopathic nosodes. And as far as I know every one of the fully clear dogs was vaccinated (mine was). The breed goes back to only half a dozen post world war II dogs and there's good indication that probably two of these had the genes for the malformation and that it has, particularly through intense use of popular studs, become more and more concentrated.

The clearest known line is in Australia. It may well be that that a handful of lines isolated from the use of several very popular US and UK studs are the least affected. Studs have an inordinate influence on the breed because they can sire hundreds of puppies and thus distribute their DNA widely while a bitch may have only 3-15 puppies in a lifetime with her genetic contribution. So researchers have been saying for a couple of years that at the very least, breeders should be MRIing studs.

Bet
23rd July 2008, 03:04 PM
I have contacted Karlin privately with my thoughts on this discussion,

Now I have thought that for others interested on the List about this discussion,more information can be obtained on the UK Cavalier Club Web Site

www.thecavalierclub.co.uk
where there is an Article by Dr Sarah Blott ,who is Researching the SM Problem in Cavaliers ,at The Animal Health Trust ,here in Britain

The Article is called

Genetics of Syringomyelia and Breeding Strategies to reduce Occurance.

In it she details what her plans are ,including setting up a Web Page where people can submit information directly .

She hopes to have this in operation in the next few weeks

I really think that until this scheme is in operation ,would it not be better if everyone waited until it's discovered what Dr Blott wants for her Research Work

This Article was discussed at the recent UK Cavalier Club Liason Meeting ,and was sent to all Cavalier Club Members

Bet

Karlin
23rd July 2008, 03:58 PM
That will be very useful to have a web page for submissions. :thmbsup:

However Sarah isn't the only person doing research, and many have been setting up scanning clinics to help obtain information, and/or requesting information for a database of study, over the past several years. Sarah Blott will be able to build on information already available thanks to many committed pet owners and breeders but there's far more out there than has been submitted to add to knowledge and hence, progress has been delayed again and again. :( Already Sarah Blott's work seems to be running well behind the timetable proposed at Rugby 9 months ago, when she requested scanning data from breeders at the event:

From the notes on the Canadian CKCS club site:


First part of project includes making enquiries from breeders as to what they want. They also have to
make an estimation of Heritability and Genetic Correlation. This will have to be done in the first 6
months of the project. This would allow them to come up with Breeding Values for the dogs.
- Says they already have Pedigree records from the UK Kennel Club and also have data from C.
Rusbridge and P. Knowler.
- Need MRI scans and 5 Generation Pedigrees from anyone.
- Pedigree data will look at population structure. How related are dogs in the current population? How
many dogs are used for breeding? This information will inform our modelling. Need to know where
they are starting from
- The second year of the project will be taken up with this modelling where they look at different
breeding strategies and what the possible outcome might be.
- At end of the 2 year project, they hope to have come up with set of recommendations.

The project was supposed to finish in Feb 2010 so we are past the first 6 months when data were to be submitted. Hopefully they will now get what they need to start.

*Pauline*
24th July 2008, 02:12 AM
There's got to be a link it cant be Head Shapes,Those other Small Breeds have different Head Shapes and are of a different Sizes
so what is going on ,

Has any-body any thoughts about this. Bet

Only going on what I have been told so correct me if I'm wrong but in recent years it's been the smaller Cavaliers that have been winning shows and some breeders have been trying to create 12lb dogs, not helped by the fact that that the standard is 12 to 18lb. As this is a recent thing it may have no relevance but, any small breed has been created from smaller and smaller dogs if you think they all originated from wolves. This "downsizing" is the only link I can see as like was said, SM is in other small breeds more so than larger breeds.

Bet
24th July 2008, 11:50 AM
Could I be permitted to answer Karlin's mention about Vaccines

There is to be a Vaccine to be being produced in America shortly by a Vaccine Company for use only for Small Breeds of Dogs ,this is after the result of a Survey carried out on Adverse Reactions from Vaccinations.

For this to be being done ,there must have been some cause for concern from the Vaccination Survey/

Also it has been stated that SM can appear in a Dog 6 to 9 months after the Vaccination .

Could I emphasize again ,that it could only be those Dogs who are Genetically Susceptible to their Vaccinations who are having Adverse Reactions ,

This is according to Dr Jean Dodds the well known Immunologist in America.

I just dont have a clue asto why Small Breeds are suffering rom SM ,unfortunately neither it seems do the Researchers.

Pauline ,it might be as you say ,since so many Small Breeds have this disease

Bet

Karlin
24th July 2008, 12:36 PM
The skull size issue has remained of interest to breeders. Researchers so far haven;t really found any significant correlation as they see SM in large skulled dogs and smaller skulled dogs. Clare Rusbridge has pointed out however that cavaliers have particularly large brains -- about labrador sized -- in a skull that is usually too small to contain it. It is rare to find a cavalier with any space all the way around the brain as is normal -- it is almost always being compressed at the back, which is the area that controls motor functions and physical sensations. This alone may well be why cavaliers are generally seen as being sensitive around the neck (vets always say this!).

As I've noted, several cavaliers that have never had vaccines and which instead received holistic nosodes are known to be affected by SM.

No one knows what causes MVD either, nor most afflictions of dogs, humans, cats etc. Genetic work in recent years and the possibility of sequencing has revealed a lot of genetic predisposition though for many of these condition. Not knowing the cause doesn't mean a condition isn't understood in other ways or that there isn't significant evidence to understand aspects of a condition. :thmbsup: There's very strong evidence of inheritance -- good and bad -- already with cavaliers that can be traced in some lines. The fact that SM-clear cavaliers tend to have many close relatives around them that also scan SM-clear is one such strong indication on the positive side. The fact that puppies from SM-affected cavaliers even when asymptomatic tend to produce only SM-affected offspring is also very strong evidence. More scans, more research should produce a bigger and better picture.

merlinsmum
24th July 2008, 02:41 PM
Only going on what I have been told so correct me if I'm wrong but in recent years it's been the smaller Cavaliers that have been winning shows and some breeders have been trying to create 12lb dogs, not helped by the fact that that the standard is 12 to 18lb. As this is a recent thing it may have no relevance but, any small breed has been created from smaller and smaller dogs if you think they all originated from wolves. This "downsizing" is the only link I can see as like was said, SM is in other small breeds more so than larger breeds.

Again, just my opinion .... could it be as Pauline says the tendency towards the "fashionable":mad: "tea pot" sizes that could contribute to the skull size - when you look at the smaller dogs there is a higher incidence of a more rounded skull shape(which would leave less room for the brain) rather than the "flat top" of a "normal" size cavalier???? I wonder if many more dieseases will pop up in smaller breeds due to the popularity of "teapot" dogs - Many thanks to the Hiltons of this world....:(

Bet
24th July 2008, 03:41 PM
Could I mention that I'd contacted Dr D Marino at LIVS in America ,asking him the following questions ,a couple of weeks ago.

I mentioned about it being said That Cavaliers' Brains being too Large for their Skulls compared to other Breeds of Similar Size.

I asked is it the same for some other Small Breeds of Dogs ,are their Brains also too Large for their Skulls

Also I asked is it only Cavaliers with SM who have the Larger Brains

Here is his reply .

These are good questions ,but the Scientific Information just is'nt available to answer these questions .

Brain Volumn Studies in both Cavaliers and Other Breeds with Vhiari is being worked on currently at my Hospital

Bet