The average lifespan of the Cavalier ranges from 9 to 14 years, depending on the hereditary health and defects to which the individual dog is subject. A healthy dog with no or only mild defects will usually live from 12 to 14 years in good health. However, as with many breeds of pedigree dog, the Cavalier has been subject to various hereditary problems that can seriously impede its health and lifespan. Fortunately there are now breed specific health schemes to test for many of these. It is always advisable to ensure that a puppy has been bred from health tested parents.
Mitral Valve Disease (MVD)
The mitral valve controls the blood flow between the left auricle and ventricle of the heart. With the onset of mitral valve disease the valve weakens, causing blood to leak through the valve between heartbeats. As the mitral valve deteriorates it produces what are called heart murmurs, and eventually congestive heart failure. It is the most common cause of death in Cavaliers (a Kennel Club survey showed that over 40% of Cavalier deaths are cardiac related).
It is not uncommon in either dogs or humans for the heart to weaken with age. MVD is usually a disease of old age, but the Cavalier is particularly susceptible to the early onset of this condition. The condition is polygenic, meaning that it is affected by multiple genes, and therefore all Cavalier breeding lines are susceptible.
Statistically it is calculated to be present in more than half of all Cavaliers by the age of 5, and it is rare for a 10 year old Cavalier not to have a heart murmur (it is common for a dog of any breed to have a heart murmur by the time they are 10 years old). However it can appear in Cavaliers as young as 2 years (occasionally even younger), and of course these dogs should never be used for breeding.
Testing By a Cardiologist
All dogs have their heart checked during their annual check-up when they receive their boosters. But Cavaliers intended for breeding should be tested by a qualified cardiologist, who will listen to the dog’s heart with a stethoscope for signs of a murmur. This test has long been available and is usually carried out at intervals of 12-18 months. A certificate is issued giving the cardiologist’s assessment of the heart on a scale of 0 to 6. A breeding dog should be rated 0-1 unless he/she is a senior (i.e. over 6), in which case 2 is acceptable.
Kennel Club Cavalier Heart Scheme
The cardiology test picks up heart murmurs, but the Kennel Club has devised a heart scheme especially for Cavaliers in conjunction with the Veterinary Cardiovascular Society to assess the health of the mitral valve. This test is in two parts, the first part being the cardiology test described above. In the second test, sometimes referred to as the doppler, the cardiologist will use an echocardiogram to scan the dog’s heart valves and give a mitral valve prolapse grade. The two gradings are recorded on a certificate resulting in an overall grading of green, amber or red. Ideally only dogs graded green should be used for breeding, although an amber graded dog might be used in exceptional circumstances.
Dogs must be 18 months to 2 years old to participate and must be tested again at 4 and 6 years. Stud dogs are being tested at 8 and even 10 years if they are still on active service. More latitude is given in grading older dogs, but it is still recommended that only dogs graded green are used for breeding.
The test results are sent to the Kennel Club but they are not at present being recorded on the dog’s registration papers. It is envisaged that this will change as the test becomes more widespread.
You can find out more about the Kennel Club Heart Scheme here.
Reducing the Risks of MVD
Breeding from heart-healthy dogs reduces the risk of early-onset MVD but does not eliminate it. The genetics behind it are still not properly understood, so there is no DNA test that can assess a dog’s susceptibility. But the most important thing you can do to reduce the risk of heart problems is not to allow your dog to become obese. Unfortunately pet obesity is an increasing problem, partly because people fail to see that their dog is overweight and then refuse to believe the vet who tries to tell them.
On one of her annual checkups my Milly weighed a kilo more than she should, so I know how easy it is to feel defensive. And a single kilo might sound trivial, but when you reframe it as more than 10% of her entire body weight you can see why it matters. Excess weight is the arch enemy of the Cavalier. For more about feeding your dog healthily go here.
Eye Disorders
About 25% – 30% of Cavaliers are estimated to have some sort of eye disorder. Many (but not all) are hereditary, so the British Veterinary Association have developed tests to identify them (most of these conditions can affect all breeds, not just Cavaliers). All breeding dogs should be subject to these tests, which routinely cover 11 individual conditions.
Congenital inherited conditions
- Goniodysgenesis/Primary Glaucoma (G)
- Persistent Hyperplastic Primary Vitreous (PHPV)
- Multifocal/Total Retinal dysplasia (MRD, TRD)
- Collie Eye Anomaly (CEA)
- Congenital Hereditary Cataract (CHC)
Non-congenital inherited conditions
- Hereditary cataract (HC)
- Primary Lens Luxation (PLL)
- Generalised/Central Progressive Retinal Atrophy (GPRA, CPRA)
- Persistent Pupillary Membrane (PPM)
Before testing, the dog will be given eye drops to dilate the pupils. The test is carried out in a darkened room using a special torch. For KC registered dogs a certificate is issued with respect to the known inherited eye disease(s) for the breed under examination. A breeding dog should test as “Unaffected”.
The test results will normally be sent to the Kennel Club to be recorded on the dog’s registration papers. It is known as the BVA/KC/ISDS (British Veterinary Association/Kennel Club/International Sheep Dog Society) Eye Scheme.
Curly Coat/Dry Eye and Episodic Falling (CC/DE & EF) Syndromes
These are recessive genetic conditions, and therefore only affect dogs who have inherited defective genes from both parents. A dog may itself be perfectly healthy, yet still be a carrier and therefore able to pass the conditions on to their offspring. Only if neither parent dog is carrying the condition can you be sure of their puppies not being affected.
In 2011 scientists working in the Kennel Club Genetics Centre at the Animal Health Trust identified the mutations responsible for causing dry eye and curly coat syndrome and episodic falling in Cavaliers. They were therefore able to develop DNA tests to identify which dogs were carrying the faulty genes. All breeding dogs should be subject to the tests and be certified clear.
Curly Coat/Dry Eye (CC/DE) Syndrome
While these two conditions can be found individually across multiple breeds, the dual condition is unique to the Cavalier. They might not sound like major health problems, but the distress they cause to the affected dog usually results in them being put to sleep. Of course affected dogs should not be used for breeding, but the condition is a recessive one and therefore many more dogs carry the gene than are actually affected by it.
Dry eye in dogs leads to a range of painful and debilitation problems, ultimately leading to blindness, and the affected dog needs constant lubrication with eye drops to prevent the eye drying out. Curly coat is literally that, but the excessive curl is a symptom of more serious problems, affecting the skin on the dog’s paws, nose and other areas not covered with fur. The unprotected skin thickens and hardens, causing pain and discomfort and often leading to secondary complications such as infections. The condition affects both sexes equally and is usually evident at birth.
Episodic Falling (EF) Syndrome
This condition is unique to the Cavalier and describes a tendency to develop uncontrolled muscle contractions which cause rigidity, either in the back legs or in all four, and bending of the spine. When all 4 legs are affected it can lead to collapse and difficultly in recovering their footing, hence the name.
It was once thought to be a muscular disorder, but is now known to be neurological, and in past was sometimes misdiagnosed as epilepsy. However unlike epilepsy the dog remains conscious throughout. It ranges from mild cases of occasional falling to seizure-like episodes lasting hours. In mild cases the condition can stabilise as the dog gets older and cause relatively few problems.
Being genetic the condition cannot be cured, but in some cases it can be managed with medications such as Clonazepam and Acetazolamide. But in other cases these drugs can produce side effects that can be as bad as the condition itself. The condition affects both sexes equally and is usually evident before the age of 1. About 1% of Cavaliers are affected by the condition, with 19% being carriers.
Testing for CC/DE and EF Syndromes
These are DNA tests using swabs taken from the inside of the dog’s cheek. The swabs are sent away to a laboratory and the results are available within a few days. The laboratory will also send the results to the Kennel Club to be recorded on the dog’s registration papers.
Any registered dog can be checked for health screening at the Kennel Club website.
MCADD
MCADD is another genetic disorder which has only recently been found in the Cavalier. Affected dogs cannot metabolise fats normally when their bodies run out of glucose, which causes them to suffer from low blood sugar and can cause seizures, coma or sudden death.
It is caused by a fault in the gene which controls the production of an enzyme called medium-chain acyl-CoA dehydrogenase (MCAD). In dogs affected with MCADD the enzyme either does not function correctly or may be missing altogether. This can cause a severe reaction when affected dogs consume fats, especially MCT oil, which is often recommended as a miracle supplement for brain and heart health. Symptoms include lethargy, loss of balance or coordination, disorientation, breathing difficulties, seizures and convulsions.
These signs can be symptoms of other conditions, so it is important to keep records. With early diagnosis MCADD can be managed successfully by diet.
Testing is available by swab, although as a new test it is not yet widespread. The condition is recessive, so if one parent has been tested clear any puppies will not be affected.
Syringomyelia
This is a condition affecting the brain and spine, caused by a malformation in the lower back of the skull which reduces the space available to the brain, compressing it and forcing it through the opening into the spinal cord. This blocks the flow of the cerebral spinal fluid around the brain and spine and causes pressure which results in the formation of fluid pockets or syrinxes (hence syringomyelia).
The effect on the dog can range from mild discomfort to sever pain and partial paralysis.
It can affect any breed of dog but is particularly associated with the Cavalier. It is a non-contagious disease caused by conformation rather than genetic inheritance or infection. Thus it is only hereditary insofar as physical characteristics can be inherited, and by its nature is more likely to affect smaller breeds. Nevertheless dogs from a line in which syringomyelia has been prevalent are more likely to breed offspring with the condition, and therefore should not be used for breeding.
Although symptoms can appear at any age, they usually do so between 6 months and 4 years of age. They include sensitivity around the head, neck and shoulders (especially when wearing a collar) and ‘air scratching’, i.e. making scratching motions without actually making physical contact with the body; hence syringomyelia’s colloquial description as the neck scratchers disease. Severe cases can show a lack of awareness of body position, clumsiness and falling with no obvious cause.
Diagnosis is through an MRI scan (Magnetic Resonance Imaging), a process giving much greater clarity than an ordinary x-ray. Treatment can be through drugs or, in severe cases, surgery. However the surgery is very expensive, risky (there are major blood vessels in the area and, if they are damaged, the dog can quickly bleed to death) and can only be carried out by specialist teams in a few locations. Even then it is possible for the symptoms to reappear at a later date. Therefore the most likely course of action in severe cases is for the dog to be put to sleep.
Ear Disorders
Cavaliers may be predisposed to a form of congenital deafness, due to a lack of formation or early degeneration of receptors in the inner ear, although this is relatively rare. They are also prone to develop a progressive hearing loss, which usually begins during puppyhood and progresses until the dog is completely deaf, usually between 3 and 5 years old. This progressive deafness is believed to be caused by a degeneration of the hearing nerve, rather than the lack of formation or early degeneration of the inner ear receptors.
There is also the physical fact of their long, heavy ears which must impede the absorption of sound by the eardrums. Plus the fact that there’s none so deaf as those that don’t want to hear!
