Mitral Valve Disease Breeding Protocol
for the Cavalier King Charles Spaniel


If a mitral valve murmur is detected before the cavalier's fifth birthday, that dog's mitral valve disease (MVD) is defined as "early-onset". Early-onset MVD has been found to be "highly heritable" in the cavalier King Charles spaniel breed, and "selection against the disease should be successful.", according to an April 2011 research report.

Veterinary specialists have designed breeding guidelines to eliminate early-onset mitral valve disease in Cavalier King Charles spaniels in the United States and the United Kingdom. The guidelines (called the MVD Breeding Protocol) were strongly advised to US breeders in 1998 (and in 1996 to UK CKCS breeders) by a group of veterinary cardiologists and a geneticist who had dedicated years of study to mitral valve disease in Cavaliers.*

*In other countries, veterinary cardiologists and geneticists have designed similar breeding guidelines, either by auscultation (listening to the flow of blood through the mitral valve using a stethoscope), as in Canada and Sweden, or by electrocardiograph (ultrasound), as in France.

Both the UK's Cavalier King Charles Spaniel Club and the Cavalier King Charles Spaniel Club of Canada have endorsed the MVD Breeding Protocol.* In 2001, the Swedish Kennel Club introduced a modified, but mandatory version of the MVD Breeding Protocol for all cavaliers, and in 2011, the Dutch Kennel Club introduced its own mandatory, modified version of the MVD Breeding Protocol for all CKCSs being bred. The Cavalier King Charles Spaniel Club, USA endorsed the full MVD protocol from 1998 to 2010, when the leadership of that club decided to replace the protocol with a fictitious, watered-down version which no panel of veterinary cardiologists has ever recommended and is destined to fail.

 *However, neither the UK CKCS club nor the Canada CKCS club requires that the dogs be examined by veterinary cardiologists.

Since 1998, only an insignificant minority of breeders of Cavalier King Charles spaniels in the United States have followed these guidelines. In the 16 years since then, the vast majority of such breeders have squandered at least five generations (at 2.5 years per generation) of Cavaliers towards eliminating early-onset (onset before age 5 years) mitral valve disease.* By shunning the MVD Protocol and actually increasing the breedings of Cavaliers in violation of the MVD Protocol, the great majority of American breeders have acted irresponsibly and in callous disregard for the health and welfare of future generations of Cavaliers.

*For example, in 2010, 55% of all cavalier litters registered with the UK Kennel Club had at least one parent under the age of 2.5 years.

The MVD Breeding Protocol

MVD Breeding Protocol

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In Depth

-- history of the protocol

The MVD Breeding Protocol has been designed to eliminate early-onset mitral valve disease. Veterinary cardiologists throughout North America and Europe conducted studies of MVD in Cavaliers in the 1990s.

Dr. James Buchanan, Penn Vet SchoolBruce KeeneA group of four world renowned veterinary cardiologists, Doctors Andrew Beardow from England, James Buchanan (right) from the United States, Virginia Luis Fuentes from Scotland, and Bruce Keene (left) from the US, and an internationally respected geneticist, Professor Lennart Swenson from Sweden, each presented reports on the results of their professional studies about the disease in1998. Their conclusions:

• MVD is the leading cause of death in cavaliers;
• It is a hereditary, genetic disorder;
• There has been no statistical improvement in cavaliers' mitral valves in the eleven years since the first studies; and
• The disease can be decreased and the age of onset delayed by following guidelines of only breeding cavaliers who are over the age of 2.5 years, have hearts free from MVD murmurs, and have parents whose hearts were MVD murmur-free at age 5 years. No cavaliers should be bred which have murmurs before age 5 years.

Anne Eckersley RobinsThese experts presented their findings and conclusions at a symposium in May 1998, which was sponsored by the Cavalier King Charles Spaniel Club, U.S.A. (CKCSC,USA).* Under the leadership of its then president, C. Anne Eckersley-Robins (left), the board of directors of the CKCSC,USA then also endorsed the MVD Breeding Protocol in 1998.

* A similar presentation was made in November 1996 before the UK Cavalier King Charles Spaniel Club.

Professor Lennart SwensonThese guidelines were developed by the Swedish Kennel Club, and are based upon that club's successful efforts to reduce hip dysplasia in Rottweilers. Between 1976 and 1994, the percentage of Rottweilers diagnosed with hip dysplasia decreased from 36% to 11% by following a similar breeding program. Professor Swenson (right) reported that hip dysplasia is a multifactorial, polygenic trait, and it is believed MVD is also.

He pointed out that it is not realistic to expect to eliminate the causes of mitral valve disease by any breeding program without further research into the reason for the high prevalence of the disorder in cavaliers. Instead, the goal is to postpone the onset of the disease so that all cavaliers die a natural death before MVD becomes a health problem.

Professor Swenson believes that if the recommended breeding guidelines are followed by all breeders, we would see improvement after the first generation and significant progress towards delaying the onset of MVD over two to three generations. Mitral valve disease is not controlled by a single gene, but there may be one dVirginia Luis Fuentesominant gene which controls the worst (earliest onset) 30% of MVD cases. He stated that if that is correct, this worst gene would be the first one to disappear once the breeding guidelines are universally followed.

Dr. Luis Fuentes (right) reported on the British studies, which began in 1987 and showed that 50% of all 5 year old cavaliers had MVD murmurs, and all examined Cavaliers over the age of 10 had murmurs. The English Cavalier King Charles Spaniel Club has endorsed the Swedish guidelines, and it also is publishing a registry of all cavaliers over age 5 years with murmur-free hearts.

Andrew BeardowDr. Beardow (left) explained that the guidelines call for each breeding cavalier to be examined annually by a veterinary cardiologist using a stethoscope. He said that, compared to an echocardiographic examination, the use of a stethoscope (called auscultation) by a cardiologist is 90% accurate in detecting MVD. In view of the relative wide availability and low cost of auscultation diagnosis, it is preferred over more expensive alternatives. Compliance with the guidelines is enhanced by using relatively inexpensive, simple, and effective measuring methods. Also, the speakers expressed their concern that the testing device be specific enough to identify MVD but not so sensitive as to eliminate all of the breeding stock.

Most importantly, the experts emphasized that, to be effective, the breeding guidelines must be widely supported and uniformly implemented. The biggest reason that breeding guidelines fail is that the breeders do not follow them. Therefore, the results of the tests should be published for all to see. The English Cavalier Club's registry of murmur-free dogs is aimed at encouraging breeders to follow the guidelines.

A printable  transcript of the May 1998 MVD symposium proceedings is available here.

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-- since the 1998 symposium

--- United States cavalier clubs

CKCSC,USA Up-Side-DownThe board of directors of the Cavalier King Charles Spaniel Club, USA (CKCSC,USA) promptly endorsed the MVD Breeding Protocol as recommended guidelines in May 1998, the same weekend that the MVD symposium was presented to its club members. The club also started a registry of all cavaliers which were certified to have been murmur-free over the age of five years, called the CKCSC,USA Health Registry. However, in 2002, the CKCSC,USA began ignoring the protocol, including removing it from the club's Internet website and firing its Health Registry secretary. In 2010, the CKCSC,USA's board pretended that it had never endorsed the protocol in 1998 and approved a set of worthless breeding guidelines which no cardiologist ACKCSC Up-Side-Downresearchers had ever suggested would be effective. See here for details.

The American Cavalier King Charles Spaniel Club (ACKCSC), which is the cavaliers' parent club in the American Kennel Club (AKC) has never acknowledged the existence of the MVD Breeding Protocol. See here for details.

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--- CKCSC of UK

UK Cavalier ClubThe United Kingdom CKCS club's version of the MVD Breeding Protocol does not require that veterinary cardiologists perform the stethoscopic examinations for heart murmurs, although it does require that cavaliers over the age of five years be examined by cardiologists in order to qualify for inclusion on the club's "Over Five" list.

Since the 1998 report, studies conducted by veterinary heart and genetic specialists have confirmed the efficacy of the MVD Breeding Protocol. In a 2000 research study of 4,255 CKCS heart examinations, Dr. James Wood of the Animal Health Trust in the United Kingdom reported that:

• MVD is the major killer of cavaliers under 10 years of age.
• Veterinary cardiologists were better able to identify early mitral valve murmurs than were non-specialist veterinarians.
• The parent's heart status can predict the offspring's future heart status.
• The offspring were ten to twenty times more likely to be free of MVD murmurs if the sire's heart was clear of murmurs at ages nine to eleven years.

In a 2009 report by UK veterinary cardiologist Simon Swift to the UK's Cavalier Club, he stated that 50% of cavaliers still are developing MVD murmurs by their fifth birthday. This is because most breeders are not following the MVD breeding protocol.  At the November 2010 "Cavalier Health Day", sponsored by the UK Cavalier Club, Mr. Swift reiterated the importance of breeders following the MVD breeding protocol.  He told the assembled breeders that the protocol was "rigorous advice that should be properly followed."

In an October 2016 statement, cardiologist Swift wrote:

"Examining dogs on the database for the period between 2006 and 2010 showed only four per cent of dogs had followed this breeding advice -- that is, had parents or grandparents tested clear older than five years."

As recently as 2009, the chairman of the UK's Cavalier King Charles Spaniel Club stated: "There are many members who are still not prepared to health check their breeding stock, and of those who do, it would appear that many would not hesitate to breed from affected animals."

In a November 2016 press release, the UK Kennel Club announced that it has approved a health testing scheme for cavalier King Charles spaniels, with the intended result of "dramatically" improving the heart health of the CKCS. Apparently, the move was motivated by the January 2016 article reporting on Denmark's mandatory testing policy.  The UK program will consist of veterinary cardiologists examining cavaliers to determine if each dog has a mitral valve murmur. An echocardiograph scan also will be performed and sent to Dr. Lisbeth Høier Olsen in Denmark, for her to measure the heart. Each dog will be issued a certificate from the University of Copenhagen, with both a murmur and mitral valve prolapse score. The Kennel Club will record the certificate results on the dog's registration record and made available publicly. The Kennel Club also intends to update MVD breeding recommendations for cavaliers.

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--- CKCSC of Canada

Cavalier Club of CanadaOn the bright side, since 2011, the Canadian cavalier club has endorsed the MVD breeding protocol. On its website, it states:

"The Cavalier King Charles Spaniel Club Of Canada has recently included the recommendation within its Breeders' Guidelines that Breeders breed Cavalier King Charles Spaniels that are at least 2.5 years old and murmur-free that have parents that were murmur-free at age 5 years."

However, the Canadian club's version of the MVD Breeding Protocol does not require that veterinary cardiologists perform the stethoscopic examinations for heart murmurs.

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--- Swedish Kennel Club

Swedish Cavalier ClubThe Swedish Kennel Club and the Swedish Cavalier King Charles Spaniel Club (Cavaliersällskapet) follow a mandatory modified version of the MVD Breeding Protocol. In Sweden, to be eligible for breeding, all cavaliers must be tested clear of MVD murmurs at age 24 months, and their parents must have been tested clear of MVD murmurs at age 48 months. This breeding protocol was begun in 2001 and, ironically, is weaker than the MVD protocol devised by Swedish veterinary geneticist Lennart Swenson.

Dr. Jens Häggström & CavalierThe Swedish clubs do not require that all stethoscopic examinations of the cavaliers' hearts be performed by veterinary cardiologists, which is a requirement of the MVD Breeding Protocol. However, all Swedish veterinarians who are licensed to issue clear-heart certificates for this registry must pass an auscultation examination conducted by Sweden's top cardiologists/researchers, Drs. Jens Häggström (left) and Clarence Kvart (below).

Dr. Clarence KvartIn a 2010 study by cardiologist Dr. Clarence Kvart of the mandatory Swedish CKCS club breeding protocol, Dr. Kvart reports that that the prevalence of MVD in six-year-old cavalier King Charles spaniels, born 2001 and 2003, is at least 50% and lacks signs of decrease despite the current breeding program introduced in Sweden 2001.  The Swedish clubs have declined to toughen their program to match Prof. Swenson's recommendation.

Nevertheless, in 2013, the Swedish Kennel Club reported that of 988 cavaliers tested in 2012 for mitral valve disease, only six under the age of four years had murmurs, and only 61 of all of them had murmurs.

By way of comparison, a pair of September 2005 studies [1] [2] of Swedish cavaliers from 1995 to 2000 showed that 23% were dead by eight years, and 48% were dead by ten years. Those researchers stated:

"Heart disease in the Cavalier King Charles spaniel accounts for over 50% of deaths in that breed (in dogs under 10 years of age) and for over one-quarter of the heart deaths in the insured population [of all breeds]. Although heart disease in Cavalier King Charles spaniels is well recognized, these statistics give further insight into the impact of this cause of death in this breed."
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--- Dutch Kennel Club

Cavalier Club NederlandSince 2011, the Dutch cavalier King Charles spaniel club (Cavalier Club Nederland) and the Dutch Kennel club also have been following a mandatory modified version of the MVD breeding protocol. In theirs, all breeding stock cavaliers must have their hearts examined by ultrasound at age one year or prior to breeding. Thereafter, their hearts must be re-examined by auscultation by a specialist. If a mitral valve murmur is detected before the dog's fifth birthday, it may not be bred.

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--- Danish Cavalier Club

Danish Cavalier King Charles Spaniel ClubThe Cavalier King Charles Spaniel Club of Denmark (Cavalierklubben), and the Danish (Dansk) Kennel Club (DDK), have had a mandatory MVD breeding protocol, using both auscultation and ultrasound, since 2002.  The protocol is a modification of the standard MVD protocol. Currently, through May 2017, the male and female breeding dogs first must be examined by auscultation and echocardiograph at the age of 18 months or later by veterinarians approved by the Danish Kennel Club. If a dog is found to be clear of MVD, it is issued a breeding certificate which is valid until the dog reaches the age of 4 years and a month. If the dog is to be bred after that age, it must be re-examined, found clear of MVD, and receive another certificate, which, for females, is valid for life. For males, the second certificate is valid until age 6 years and a month. If the male is to be bred after that age, he must be examined and ceritifed a third time.

Lisbeth Høier OlsenIn a June 2013 report to the clubs and to the ACVIM, Dr. Lisbeth Høier Olsen (right) stated that in 2011, 997 Danish CKCSs were examined under the Danish Kennel Club's mandatory breeding program during the period from 2002 to 2011. Each dog was evaluated from one to four times for a total of 1,380 examinations by auscultation and echocardiography. The study found that the risk of having MVD in 2010-2011 was compared to the period 2002-2003 for cavaliers which were the offspring of parents in the mandatory breeding protocol and those which were not (such as imported cavaliers). In 2010-2011, the examined dogs within the club's breeding protocol had a 71% reduced risk of having MVD than dogs in 2002-2003. As for offspring of parents not subject to the breeding protocol, the reduced risk of having MVD did not reach statistical significance.

Comparing the Swedish and UK cavalier breeding protocols with those of Denmark, Dr. Olsen stated:

"The Danish breeding program (mandatory, auscultation and heart scan at 1½, 4 and dogs 6 years) seems more effective than the English and Swedish (only auscultation, but every year, and the inclusion of parents animal cardiac status). The Swedish program is mandatory while the UK voluntarily ."

At a meeting of the Euoropean Society of Veterinary Cardiology in September 2014, Dr. Olsen and Jens Häggström and Simon Swift presented a written summary of their evaluations of the three breeding programs. Their conclusions will be published in a scientific paper in 2015. Based upon that input, the DKK ordered that, beginning in June 2015, the mandatory cavalier breeding protocol continue through May 2017.  The DKK stated that, if in the course of this two-year period any new studies demonstrate the same or better effect of simpler or cheaper breeding programs, the DKK and the Danish cavalier club can enter into dialogue about whether the current breeding protocol be changed.

In a January 2016 article, a team of Danish and Swedish cardiologists (A.C. Birkegård, M.J. Reimann, T. Martinussen, J. Häggström, H.D. Pedersen, L.H. Olsen) reported that the Danish Kennel Club's 2001 mandatory MVD breeding scheme has reduced the risk of having a mitral regurgitation murmur caused by MMVD by 73% among 997 cavalier King Charles spaniels. They re-stated Denmark's MVD breeding guidelines as:

1. Dogs examined at 1½ years of age or older were approved for breeding until 4 years of age if cardiac health criteria were fulfilled.

2. To continue breeding after 4 years of age, the dogs had to be reexamined. In January 2007, an additional restriction was added, requiring a reexamination after 6 years of age for male dogs.

3. At all examination time points, dogs were excluded from breeding if they had MVP (mitral valve prolapse by echocardiograph) grade 3 or a mitral regurgitation murmur grade 3 or higher.

4. Dogs with grade 2 murmurs were excluded if they had:
• MVP grades 2 or 3;
• Mitral regurgitation murmur of 1 at a maximum combined with a MVP grade 2 at a maximum; or
• A grade 2 murmur combined with a degree of MVP not above grade 1.
• Before 2007, dogs with a grade 3 MVP were approved if they had a murmur grade not above 1.

The researchers concluded:

"Our study shows that a breeding scheme based on cardiac auscultation and echocardiography markedly decreased the risk of having a mitral regurgitation murmur caused by MMVD after an 8- to 10-year period. The reduction in risk was only significant for offspring where both parents had been approved by the breeding scheme (PB), not for offspring where 1 or both parents not were approved by the breeding scheme (non-PB). The risk of having moderate to severe MVP (MVP > 1) was not decreased after the 8- to 10-year period, but PB had lower risk of MVP > 1 than did non-PB within the years 2010 and 2011. ... A mandatory breeding scheme based on auscultation and echocardiography findings significantly decreased the prevalence of MMVD over the 8- to 10-year period. Such a breeding scheme therefore is recommended for CKCS."
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Finnish CKCS Club--- Finnish CKCS Club

The national cavalier King Charles spaniel club in Finland (Suomen Cavalier Kingcharlesinspanieliyhdistys) and the Finnish Kennel Club (Suomen Kennelliitto -- FKC) combine forces to create a partially mandatory and partially not mandatory MVD breeding protocol. The FKC requires that cavaliers be examined by stethoscope (auscultated) before mating. If a murmur is detected, the dog may not be bred unless it first is determined by echocardiograph that it does not have mitral valve disease.

The Finnish CKCS club adds to that the recommendation that if the cavalier is under 3 years old, the dog must have no MVD murmur and either: (a) the dog's parents were MVD-clear at age 5 years, or (b) the dog is MVD-clear by echocardiograph. A revision of this breeding recommendation is being considered that would stiffen the protocol:

• If the cavalier is between 3 and 5 years old, the dog must have no MVD murmur and the dog's parents were MVD-clear at age 5 years.
• If the cavalier is between 2 and 3 years old, the dog must have no MVD murmur and the dog's parents were MVD-clear at age 6 years.
• If either of the male cavalier's parents had an MVD-murmur before age 5 years old, the dog cannot be bred before age 5 years old and MVD-clear.
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--- French CKCS Club

Club des Epagneuls Nains Anglais (CENA)France's English Toy Spaniel Club (Club des Epagneuls Nains Anglais), which includes both cavaliers and the King Charles spaniel, instituted a voluntary MVD breeding protocol in 2001. It requires echocardiograph/color Doppler examinations for cavalier breeding stock by cardiologists, beginning at age 18 months. The echocardiograph scan either is conducted by a veterinary cardiologist or a specific still frame from the echo scan, showing the end of the cardiac contraction, can be submitted to the club for review and processing by the club's cardiologist, Dr. Gérard Haroutunian.

The club has established this five-stage grading system for categorizing the existence and degree of MVD in each dog:

• Stage/Grade 0: The mitral leaflets are intact; no thickening; no nodule; they close perfectly to the left ventricle throughout the cardiac contration phase.

• Stage/Grade 1: A discrete thickening or the presence of nodules, and a discrete flattening of the mitral valve leaflets (in reference to the plane of the mitral annulus). This flattening affects only the body of the leaflets and does not exceed the plane of the mitral annulus.

• Stage/Grade 2: Deformation and infiltration of both mitral valve leaflets are evident throughout the cardiac cycle. The leaflets appear elongated, are considerably flattened, and reach or exceed the plane of the mitral annulus.

• Stage/Grade 3: Deformation and mitral prolapse are even more obvious, but especially this stage is characterized by a highly visible expansion of the left atrium. These anomalies cause a failure to close and seal the valve, causing a leak itself to generate a mitral murmur. This murmur is constantly detectable in Stage 3, only slightly in Stage 2, depending on the quality of the stethoscope, the heart rate of the dog, the dog's weight status, breathing sounds, and a host ofexternal events making listening too random.

• Stage/Grade 4: Rupture of the chord(s) affects a large majority of mitral valve leaflets. Dilatation of the left atrium.

Following the initial examination at or after age 18 months, the breeding dogs must be re-examined every 18 months. The club allows dogs over age 3 years of age and in Stages 1 and 2 to be bred. Through September 2016,  over 14,500 echo examinations have been submitted to the club, which includes repeat exams of many dogs.

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-- cavalier breeders' objections

Breeders' Thumbs Down!Since 1998, only an insignificant minority of breeders of cavalier King Charles spaniels in the United States have followed the MVD breeding guidelines. In the years since then, the vast majority of such breeders have squandered at least six generations (at 2.5 years per generation) of cavaliers towards eliminating early-onset (onset before age 5 years) mitral valve disease.

We now find some cavalier breeders who claim to be following an MVD breeding protocol which turns out not to be the MVD Breeding Protocol. Some breeders have made up their own watered-down breeding protocol (something like: "try to breed" females over 2 years of age and MVD-clear, to males over 6 years and MVD-clear), which makes breeding decisions much easier for them, but which totally ignores the many years of statistical research and cardiologists' and geneticists' recommendations which has led to the MVD Breeding Protocol.

ACKCSC Up-Side-DownThe American Cavalier King Charles Spaniel Club (ACKCSC), which is the CKCS parent club of the American Kennel Club (AKC) has pointedly ignored the MVD breeding protocol and has gone so far as to even concoct a fictitious MVD breeding guideline of its own. On its website (as of this writing in 2013), the ACKCSC has stated:

"Currently, the recommended practice is to wait until a Cavalier is two years old or older before the first breeding and to know the parents and ancestral cardiac status. Cavaliers with early onset presentations of MVD (before four years of age) should not be bred and breeders need to work with the guidance of their cardiologists."

Instead of not breeding until age 2.5 years, ACKCSC claims in its baseless "recommended practice" to start breeding at 24 months, and it also shortens the definition of early-onset MVD from five years to four years. Instead of requiring that all four parents of the breeding pair be certified to be murmur-free by age five years, ACKCSC says its "recommended practice" is simply "to know the parents and ancestral cardiac status." That is a meaningless phrase apparently designed to provide AKC breeders with "cover" for ignoring the real MVD breeding protocol. It allows them to claim that, in their "wisdom" as experienced breeders, they "know the parents" and they have taken into account the "ancestral cardiac status".

The ACKCSC, as the AKC's parent club for cavaliers, has been assigned by AKC the responsibility of "the education of breed owners on the nuances of the breed, and overseeing the breed's health and welfare." So, the ACKCSC is the primary source for AKC breeders to find out about the health of cavaliers. The ACKCSC has refused to accept that responsibility, and instead, it has misled the AKC breeders about the true MVD breeding protocol in the United States.

CKCSC,USA Forever Guardian of the Cavalier BreedersIn April 2010, the Cavalier King Charles Spaniel Club, USA (CKCSC,USA) withdrew its 1998 endorsement of the MVD Breeding Protocol and replaced it with a recommended guideline even more worthless than that of the ACKCSC. The CKCSC,USA's new guideline is:

"The CKCSC,USA recommends that prior to breeding any Cavalier, the dog have 1) a clear rating at two years of age from an auscultation by a board certified veterinary cardiologist; ..."

This new worthless guideline ignores the research experts' conclusions that: (A) All four parents of the breeding pair be MVD-clear as of their 5th birthday; (B) The breeding pair be at least 30 months old and MVD-clear at the time of breeding; and (C) No cavalier be bred if diagnosed with an MVD murmur before its fifth birthday.

In October 2010, in the face of an onslaught of justifiable criticism, the board tweaked their bogus breeding recommendation thusly:

"The CKCSC,USA recommends that prior to breeding any Cavalier, the dog should have a heart clearance from an auscultation by a board certified veterinary cardiologist that is consistent with prevailing cardiology protocols; however, the CKCSC,USA recommends a minimum of a cardiology clearance at age 2.5 years by a board certified cardiologist."

So we find that the two CKCS breed clubs in the United States are not a part of the solution to early-onset mitral valve disease in the breed.  Instead, these clubs are affirmatively contributing to the problem by enabling breeders to ignore the protocol and continue to breed generations of cavaliers destined to develop early-onset MVD.

By shunning the real MVD Protocol and actually increasing the breedings of cavalier King Charles spaniels in violation of the MVD Protocol, the large majority of American breeders have acted in callous disregard for the health and welfare of future generations of cavaliers. They continue to breed untested, un-cleared, and/or under-aged cavalier King Charles spaniels in the United States, and the number of breedings and resulting litters of these early death-marked cavaliers has increased dramatically since the American breeders were warned by the experts in 1998 to stop breeding underaged cavaliers and never breed any cavalier in violation of the MVD Protocol.

Similarly, in the United Kingdom, the chairman of its Cavalier King Charles Spaniel Club stated in March 2009:

"There are many members who are still not prepared to health check their breeding stock, and of those who do, it would appear that many would not hesitate to breed from affected animals."

In 2010, 55% of all cavalier litters registered with the UK Kennel Club had at least one parent under the age of 2.5 years.

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Research News

November 2016: UK Kennel Club approves MVD testing scheme for cavaliers. UK Kennel ClubIn a November 2016 press release, the UK Kennel Club announced that it has approved a health testing scheme for cavalier King Charles spaniels, with the intended result of "dramatically" improving the heart health of the CKCS. Apparently, the move was motivated by the January 2016 article reporting on Denmark's mandatory testing policy.  The UK  program will consist of veterinary cardiologists examining cavaliers to determine if each dog has a mitral valve murmur. An echocardiograph scan also will be performed and sent to Dr. Lisbeth Høier Olsen in Denmark, for her to measure the heart. Each dog will be issued a certificate from the University of Copenhagen, with both a murmur and mitral valve prolapse score. The Kennel Club will record the certificate results on the dog's registration record and made available publicly. The Kennel Club also intends to update MVD breeding recommendations for cavaliers.

November 2016: Simon Swift calls for parents/grandparents of UK show cavaliers to meet MVD breeding protocol -- only 4% of CKCSs have been meeting that protocol. In a letter to the Veterinary Times published in October 2016, cardiologist Simon Swift called for the UK Kennel Club to require that the parents of all show CKCSs be tested and cleared for MVD at age five years. If the parents are not yet five years old, then he writes that the show dogs' grandparents meet that test standard.

He also noted:

"Examining dogs on the database for the period between 2006 and 2010 showed only four per cent of Skeptical CavalierHealth.orgdogs had followed this breeding advice -- that is, had parents or grandparents tested clear older than five years."

EDITOR'S NOTE: Dr. Swift's observation that only 4% of cavaliers being bred in the UK in accordance with the MVD Breeding Protocol is a sad acknowledgement that nearly all CKCS breeders are more concerned about their kennels' success than about the health and welfare of the dogs they produce.

November 2015: Denmark Kennel Club proves a rigorous mandatory MVD breeding protocol works. Lisbeth Høier OlsenIn a January 2016 article, a team of Danish and Swedish cardiologists (A.C. Birkegård, M.J. Reimann, T. Martinussen, J. Häggström, H.D. Pedersen, L.H. Olsen [right]) report that the Danish Kennel Club's 2001 mandatory MVD breeding scheme has reduced the risk of having a mitral regurgitation murmur caused by MMVD by 73% among 997 cavalier King Charles spaniels.

Denmark's MVD breeding guidelines are:

1. Dogs examined at 1½ years of age or older were approved for breeding until 4 years of age if cardiac health criteria were fulfilled.

2. To continue breeding after 4 years of age, the dogs had to be reexamined. In January 2007, an additional restriction was added, requiring a reexamination after 6 years of age for male dogs.

3. At all examination time points, dogs were excluded from breeding if they had MVP (mitral valve prolapse by echocardiograph) grade 3 or a mitral regurgitation murmur grade 3 or higher.

4. The degree of MVP was assessed as:
•  Grade 0 (≤1.5 mm as the sum of the maximum protrusion of the cranial, caudal and coaption point of the mitral valve according to annulus plane)
•  Grade 1 (>1.5 and ≤4.5 mm)
•  Grade 2 (>4.5 and ≤7.5 mm)
•  Grade 3 (>7.5 mm).

5. •  Dogs with grade 2 murmurs were excluded if they had MVP grades 2 or 3;
• Mitral regurgitation murmur of 1 at a maximum combined with a MVP grade 2 at a maximum; or
• A grade 2 murmur combined with a degree of MVP not above grade 1.
• Before 2007, dogs with a grade 3 MVP were approved if they had a murmur grade not above 1.

The researchers concluded:

"Our study shows that a breeding scheme based on cardiac auscultation and echocardiography markedly decreased the risk of having a mitral regurgitation murmur caused by MMVD after an 8- to 10-year period. The reduction in risk was only significant for offspring where both parents had been approved by the breeding scheme (PB), not for offspring where 1 or both parents not were approved by the breeding scheme (non-PB). The risk of having moderate to severe MVP (MVP > 1) was not decreased after the 8- to 10-year period, but PB had lower risk of MVP > 1 than did non-PB within the years 2010 and 2011. ... A mandatory breeding scheme based on auscultation and echocardiography findings significantly decreased the prevalence of MMVD over the 8- to 10-year period. Such a breeding scheme therefore is recommended for CKCS."

June 2015: Danish kennel club continues its cavalier MVD breeding protocol through May 2017. Dr. L. H. OlsenThe Danish (Dansk) Kennel Club (DKK) has ordered that, beginning in June 2015, the mandatory cavalier breeding protocol continue through May 2017.  The DKK stated that, if in the course of this two-year period any new studies demonstrate the same or better effect of simpler or cheaper breeding programs, the DKK and the Danish cavalier club can enter into dialogue about whether the current breeding protocol be changed.

The DKK based its decision upon a report presented to the Euoropean Society of Veterinary Cardiology at a meeting in September 2014, by Drs. Lisbeth Høier Olsen (right) and Jens Häggström and Simon Swift, comparing the results thus far of the Danish, Swedish, and UK breeding protocols.  Their conclusions will be published in a scientific paper in 2015. Dr. Olsen previously had stated:

"The Danish breeding program (mandatory, auscultation and heart scan at 1½, 4 and dogs 6 years) seems more effective than the English and Swedish (only auscultation, but every year, and the inclusion of parents animal cardiac status). The Swedish program is mandatory while the UK voluntarily ."

June 2013: Danish cavaliers show 71% reduced risk of MVD under a mandatory breeding protocol. In a June 2013 report to the clubs and to the ACVIM, Dr. Lisbeth Høier Olsen stated that in 2011, 997 Danish CKCSs were examined under the Danish Kennel Club's mandatory breeding program during the period from 2002 to 2011. Each dog was evaluated from one to four times for a total of 1,380 examinations by auscultation and echocardiography. The study found that the risk of having MVD in 2010-2011 was compared to the period 2002-2003 for cavaliers which were the offspring of parents in the mandatory breeding protocol and those which were not (such as imported cavaliers). In 2010-2011, the examined dogs within the club's breeding protocol had a 71% reduced risk of having MVD than dogs in 2002-2003. As for offspring of parents not subject to the breeding protocol, the reduced risk of having MVDM did not reach statistical significance.

Swedish Cavalier ClubMay 2013: Sweden's cavaliers show great progress against MVD in 2012. The Swedish Kennel Club reports that of 988 cavaliers tested in 2012 for mitral valve disease, only six under the age of four years had murmurs, and only 61 of all of them had murmurs. The Swedish Kennel Club and the Swedish Cavalier Club follow a mandatory modified version of the MVD breeding protocol. See its breeding protocol here.

The Swedish clubs do not require that all stethoscopic examinations of the cavaliers' hearts be performed by veterinary cardiologists, which is a requirement of the MVD Breeding Protocol. However, all Swedish veterinarians who are licensed to issue clear-heart certfiicates for this registry must pass an auscultation examination conducted by Sweden's top cardiologists/researchers, Professors Clarence Kvart and Jens Häggström.

2011: Dutch CKCS club implements mandatory MVD breeding tests. The Dutch cavalier King Charles spaniel club (Cavalier Club Nederland) and the Dutch Kennel club has implemented a mandatory modified version of the MVD breeding protocol. In theirs, all breeding stock cavaliers must have their hearts examined by ultrasound at age one year or prior to breeding. Thereafter, their hearts must be re-examined by auscultation by a specialist. If a mitral valve murmur is detected before the dog's fifth birthday, it may not be bred.

2011: Canada's CKCS club endorses MVD Breeding Protocol. The Canadian cavalier club has Cavalier King Charles Spaniel Club of Canadaendorsed the MVD breeding protocol. On its website, it states:

"The Cavalier King Charles Spaniel Club Of Canada has recently included the recommendation within its Breeders' Guidelines that Breeders breed Cavalier King Charles Spaniels that are at least 2.5 years old and murmur-free that have parents that were murmur-free at age 5 years."

However, the Canadian club's version of the MVD Breeding Protocol does not require that veterinary cardiologists perform the stethoscopic examinations for heart murmurs.

January 2011: UK CKCS breeders still largely ignore the MVD Breeding Protocol. In 2010, 55% of all cavalier litters registered with the UK Kennel Club had at least one parent under the age of 2.5 years.

October 2010: CKCSC,USA modifies its new phony MVD breeding protocol. In April 2010, the CKCSC,USA's board of directors replaced the REAL protocol with a worthless watered-down version, in which they stated:

"The CKCSC,USA recommends that prior to breeding any Cavalier, the dog have a clear rating at two years of age from an auscultation by a board certified veterinary cardiologist."

In the face of an onslaught of justifiable criticism, the board met in October and tweaked their bogus breeding recommendation thusly:

"The CKCSC,USA recommends that prior to breeding any Cavalier, the dog should have a heart clearance from an auscultation by a board certified veterinary cardiologist that is consistent with prevailing cardiology protocols; however, the CKCSC,USA recommends a minimum of a cardiology clearance at age 2.5 years by a board certified cardiologist."

This October revision is only a miniscule improvement over their April version and is still worthless. It ignores these essential elements of the REAL protocol:

• Do not breed any cavalier under the age of 5 years, unless its parents' hearts were free of MVD murmurs by age 5 years.

• Do not breed any cavalier who is diagnosed with an MVD murmur under the age of 5 years.

September 2010: Swedish Kennel Club's modified mandatory MVD breeding protocol is not showing progress. In a 2010 study by cardiologist Dr. Clarence Kvart of the mandatory Swedish CKCS club breeding protocol -- which is weaker than the MVD protocol recommended by Lennart Swenson -- Dr. Kvart reports that that the prevalence of MVD in six-year-old cavalier King Charles spaniels, born 2001 and 2003, is at least 50% and lacks signs of decrease despite the current breeding program introduced in Sweden 2001. The Swedish clubs have declined to toughen their program to match Prof. Swenson's recommendation.

CKCSC,USAApril 2010: CKCSC,USA dumps MVD Breeding Protocol. The Cavalier King Charles Spaniel Club, USA (CKCSC,USA) has withdrawn its 1998 endorsement of the MVD Breeding Protocol and replaced it with a recommended guideline even more worthless than that of the ACKCSC. The CKCSC,USA's new guideline is:

"The CKCSC,USA recommends that prior to breeding any Cavalier, the dog have 1) a clear rating at two years of age from an auscultation by a board certified veterinary cardiologist; ..."

This new worthless guideline ignores the research experts' conclusions that: (A) All four parents of the breeding pair be MVD-clear as of their 5th birthday; (B) The breeding pair be at least 30 months old and MVD-clear at the time of breeding; and (C) No cavalier be bred if diagnosed with an MVD murmur before its fifth birthday.

2010: ACKCSC concocts fictitious, worthless MVD breeding guideline. The American Cavalier American Cavalier King Charles Spaniel ClubKing Charles Spaniel Club (ACKCSC), which is the CKCS parent club of the American Kennel Club (AKC) has pointedly ignored the MVD breeding protocol and has gone so far as to even concoct a fictitious MVD breeding guideline of its own. On its website, the ACKCSC has stated:

"Currently, the recommended practice is to wait until a Cavalier is two years old or older before the first breeding and to know the parents and ancestral cardiac status. Cavaliers with early onset presentations of MVD (before four years of age) should not be bred and breeders need to work with the guidance of their cardiologists."

Instead of not breeding until age 2.5 years, ACKCSC claims in its baseless "recommended practice" to start breeding at 24 months, and it also shortens the definition of early-onset MVD from five years to four years. Instead of requiring that all four parents of the breeding pair be certified to be murmur-free by age five years, ACKCSC says its "recommended practice" is simply "to know the parents and ancestral cardiac status." That is a meaningless phrase apparently designed to provide AKC breeders with "cover" for ignoring the real MVD breeding protocol. It allows them to claim that, in their "wisdom" as experienced breeders, they "know the parents" and they have taken into account the "ancestral cardiac status".

The ACKCSC, as the AKC's parent club for cavaliers, has been assigned by AKC the responsibility of "the education of breed owners on the nuances of the breed, and overseeing the breed's health and welfare." So, the ACKCSC is the primary source for AKC breeders to find out about the health of cavaliers. The ACKCSC has refused to accept that responsibility, and instead, it has misled the AKC breeders about the true MVD breeding protocol in the United States.

March 2009: UK's cavalier club chairman says many club breeders ignore health checks. Mrs. Lesley Jupp, Chairman of the Cavalier King Charles Spaniel Club of the UK, stated on March 24, 2009:

"There are many members who are still not prepared to health check their breeding stock, and of those who do, it would appear that many would not hesitate to breed from affected animals."
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Veterinary Resources

Mitral Valve Disease in Cavalier King Charles Spaniels. Darke, P., Fuentes VL, Kvart C, Häggström J. Swenson L.  Proceedings, Seminar by Intervet UK Ltd and The Cavalier King Charles Spaniel Club UK. November 1996.

International Symposium on Chronic Cardiac Valve Disease in the Cavalier King Charles Spaniel. Beardow A, Buchanan J, Fuentes VL, Keene B, Swenson L. Transcript of Private Recording of Proceedings, CKCSC,USA. May 1998.

Evaluation of the Swedish breeding program for cavalier King Charles spaniels. Tobias Lundin, Clarence Kvart. Acta Veterinaria Scandinavica, Sept. 2010, 52:54. Quote: "The Swedish Kennel club and the Special club for cavalier King Charles spaniels (SCKCS) started a breeding program in 2001 with the aim of reducing MMVD in the Swedish population of CKCS. In this program, dogs are not allowed to breed until four years of age and need a heart auscultation without murmurs within eight months before mating. However, dogs are allowed to breed at an age of 24 months, if the dog and its parents are examined and no murmurs are detected. Male dogs that have a heart auscultation at seven years of age without murmurs are allowed to breed without further heart evaluation. Breeding animals whose parents have heart murmurs before four years of age are not allowed to breed. The aim of this investigation was to study the prevalence of heart murmurs in the Swedish population of six-year-old CKCS born 2001 and 2003, and to estimate if prevalence has decreased since the breeding program was introduced 2001. ... In this investigation 353 CKCS were selected as a sample of the population and 150 were examined by auscultation for heart murmurs when they reached the age of six years in 2007 and 2009. ... The effect of the breeding program was evaluated by comparing the prevalence of heart murmurs in the two groups. In 2007, the prevalence of heart murmurs was 52% (50% for females and 54% for males) and in 2009, the prevalence was 55% (44% for females and 67% for males). No significant difference was found in the prevalence of heart murmurs between 2007 and 2009 (P=0.8). For all six-year-old CKCS, the prevalence of heart murmur was 53% (females 46% and males 61%), which is higher than previous Swedish investigations. ... The result from this investigation indicates that the prevalence of MMVD in six-year-old cavalier King Charles spaniels, born 2001 and 2003, is at least 50% and lacks signs of decrease despite the current breeding program introduced in Sweden 2001."

Heritability of premature mitral valve disease in Cavalier King Charles spaniels. Tom Lewis, Simon Swift, John A. Woolliams, and Sarah Blott. Vet J, April 2011, 188(1):73-76. Quote: "Mixed model analysis of 1252 records of cardiac auscultation of ≥4- to <5-year-old Cavalier King Charles spaniels (CKCS) from 1991 to 2008 in conjunction with the Kennel Club pedigree records of all dogs registered from the mid 1980s to September 2007 was used to estimate variance parameters of premature mitral valve disease (MVD). Data were limited to dogs 4 and <5 years of age to ensure diagnostic distinction between early and late onset MVD. Cardiac murmurs were detected in 108/1252 (8.6%) dogs. Heritability estimates of 0.67 (standard error, SE 0.071) for the grade of murmur and 0.33 (SE 0.072) for the presence/absence of murmur were calculated. The variance due to clinician was 0.02 (SE 0.012) for grade and 0.03 (SE 0.017) for presence/absence of murmur. These results indicate that the presence and severity of MVD, as assessed by cardiac auscultation, in 4- to 5-year-old CKCS is highly heritable and that selection against the disease should be successful."

Evaluation of the breeding program aiming at reducing the prevalence of myxomatous mitral valve disease in cavalier King Charles spaniels in Denmark. Birkegaard AC, Reimann MJ, Häggström J, Martinussen T, Pedersen HD, Olsen LH. ACVIM Conference. June 2013. Quote: "Cavalier King Charles spaniels (CKCS) are predisposed to myxomatous mitral valve disease (MMVD). Studies have demonstrated a strong genetic background. The objective of the study was to evaluate the effect of a breeding program involving auscultation and echocardiography aimed at reducing the prevalence of MMVD. Purebred CKCS (n=997) were examined for the Danish Kennel Club mandatory breeding program during the period from 2002 to 2011. Each dog was evaluated 1-4 times with the total of 1380 examinations. Auscultation and echocardiography were performed to evaluate mitral regurgitation murmur (MRM) severity and degree of mitral valve prolapse (MVP). The risk of having MRM in 2010-2011 compared to 2002-2003 was estimated using linear regression test (exact condition binary logistic regression), adjusting for repeated measurements. In 2010-2011, dogs were estimated to have 71% reduced risk of having MRM than dogs in 2002-2003 if they were a product of the breeding program (P=0.0017). A dog was defined as a product of the breeding program if both parents where approved by the breeding program. If non-products of the breeding program (for example imported dogs with parents with unknown cardiac status) were included in the analysis, reduced risk of having MRM did not reach statistical significance (OR 1.71; P=0.06). In conclusion, the mandatory breeding program, based on auscultation and echocardiography, significantly reduced the prevalence of MMVD over the 8 to 10-year period. Therefore, such breeding programs are recommended for CKCS."

Breeding Restrictions Decrease the Prevalence of Myxomatous Mitral Valve Disease in Cavalier King Charles Spaniels over an 8- to 10-Year Period. A.C. Birkegård, M.J. Reimann, T. Martinussen, J. Häggström, H.D. Pedersen (HDP), L.H. Olsen (LHO). J. Vet. Int. Med. January 2016;30(1):63–68. Quote: "Background: Cavalier King Charles Spaniels (CKCS) are predisposed to myxomatous mitral valve disease (MMVD). Studies have indicated a strong genetic background. Objective: The aim of this study was to evaluate the effect of a breeding scheme involving auscultation and echocardiography. Animals: In the Danish Kennel Club mandatory breeding scheme, 997 purebred CKCS were examined during the period 2002–2011. Each dog was evaluated 1–4 times with a total of 1,380 examinations. Methods: Auscultation and echocardiography were performed to evaluate mitral regurgitation murmur severity and degree of mitral valve prolapse (MVP). ... Echocardiographic Assessment of MVP: The degree of MVP was evaluated by LHO or HDP (MVP observers). The degree of MVP was assessed as 0 (≤1.5 mm as the sum of the maximum protrusion of the cranial, caudal and coaption point of the mitral valve according to annulus plane), 1 (>1.5 and ≤4.5 mm), 2 (>4.5 and ≤7.5 mm), and 3 (>7.5 mm). One of the MVP observers (HDP) evaluated the MVP echocardiograms from the debut of the breeding scheme until November 2004, hereafter the recordings were evaluated by the other MVP observer (LHO). ... Breeding Guidelines and Cardiac Health Criteria: Dogs examined ≥1½ years of age were approved for breeding until 4 years of age if cardiac health criteria were fulfilled. To continue breeding in DKCS after 4 years of age dogs had to be reexamined. From January 2007, an additional restriction was decided introducing an additional reexamination after 6 years of age for male dogs. At all examination time points, dogs were excluded from breeding if they had MVP grade 3 (first a criterion from 2007) or a mitral regurgitation murmur grade ≥3. Dogs with grade 2 murmurs were excluded if they had MVP grades 2 or 3. Thus, cardiac health criteria for breeding in the MMVD breeding scheme of the DKCA were as follows: Mitral regurgitation murmur of 1 at a maximum combined with a MVP grade 2 at a maximum; or a grade 2 murmur combined with a degree of MVP not >1. Before 2007, dogs with a grade 3 MVP were approved if they had a murmur grade not >1. ... Mitral regurgitation murmur intensity and MVP status of all examined dogs became freely available from DKCA homepage after examination. Each parent needed to fulfill the cardiac health criteria for registration of their puppies in DKCA. ... The odds of having mitral regurgitation murmur or MVP > grade 1 in 2010–2011 compared to 2002–2003 were estimated using logistic regression analysis including age and sex as covariates. Odds were estimated for dogs that were products of the breeding scheme (defined as dogs with both parents approved by the breeding scheme before breeding) and non-products of the breeding scheme (defined as dogs with at least 1 parent with unknown cardiac status). Results: ... The odds of having mitral regurgitation murmur in 2010–2011 compared to 2002–2003 were 0.27 if the dogs in 2010–2011 were PB [products of the breeding scheme], reflecting a 73% decreased risk (P < .0001; Table 3 and Fig 2). Similarly, within 2010–2011, the odds of having mitral regurgitation murmur for dogs that was PB was 0.31 compared to non-PB, reflecting 69% decreased risk (P < .0001). If non-PB examined in 2010–2011 were compared with dogs examined in 2002–2003, no statistical difference in odds of having mitral regurgitation murmur was found (P = .4873). There was no significant influence of sex on odds of murmur. Odds of having a murmur were higher with advancing age. ... Our study shows that a breeding scheme based on cardiac auscultation and echocardiography markedly decreased the risk of having a mitral regurgitation murmur caused by MMVD after an 8- to 10-year period. The reduction in risk was only significant for offspring where both parents had been approved by the breeding scheme (PB), not for offspring where 1 or both parents not were approved by the breeding scheme (non-PB). The risk of having moderate to severe MVP (MVP > 1) was not decreased after the 8- to 10-year period, but PB had lower risk of MVP > 1 than did non-PB within the years 2010 and 2011. ... Conclusion and Clinical Importance: A mandatory breeding scheme based on auscultation and echocardiography findings significantly decreased the prevalence of MMVD over the 8- to 10-year period. Such a breeding scheme therefore is recommended for CKCS."

Heart testing scheme should be adopted. Simon Swift. Veterinary Times. October 31, 2016. Quote: As an RCVS and European specialist in cardiology, having been involve in heart testing and a cardiology advisor to the Cavalier King Charles Spaniel (CKCS) for the past 20 years, I read the correspondence regarding breed testing (29 August issue) with interest. As many readers will be aware, a heart testing scheme for CKCSs based upon simple auscultation, was established by Peter Darke in 1991 and refined in 2006. The CKCS Club has been very proactie in breed screening, and I and many colleagues have given up weekends attending dog shows or "health days" up and down the country to ensure as many dogs as possible were examined. The database now contains details of more than 17,000 examinations in more than 9,000 dogs, with may dogs examined multiple times. Unfortunately, degenerative valve disease is an acquired disease that starts to manifest from three to four years and, by that time, a dog's show career is over. So having show winners tested would not be an effective solution. Instead, show dogs should have certificated indicating both parents -- or all four grandparents if they are too young -- reached the age of five before developing a murmur. While this may not seem a difficult hurdle, it should be remembered up to 50 per cent of CKCSs develop heart murmurs by six years. Examining dogs on the database for the period between 2006 and 2010 showed only four per cent of dogs had followed this breeding advice -- that is, had parents or grandparents tested clear older than five years. Despite this, I have shown the average age female dogs develop heart murmurs has increased significantly during the course of the scheme, so we are having an effect, and the CKCS Club should be congratulated for its efforts.

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