by: Bridgette Evans
WHAT IS IT?
There is no better description of this defect than that written by Clare Rusbridge and published on the Cavalier King Charles Spaniel website. (http://www.thecavalierclub.co.uk)
HOW IS IT TRANSMITTED?
Syringomyelia is an INHERITED genetic defect. Transmission takes the form of an autosomal recessive gene with incomplete penetration. Therefore, an affected dog if it is line bred, then the defect takes on a more severe form and occurs earlier in the dogs life.
HOW IS IT DIAGNOSED?
Visual symptoms are the earliest indication of this defect. Accurate diagnosis is confirmed by magnetic resonance imaging (MRI) scanner, but clinical symptoms may be sufficient for diagnosis.
WHERE DID IT COME FROM?
Pedigree analysis of current confirmed cases, indicates that the gene for this defect was present in one or more of the original foundation stock. Syringomyelia and similar type defects are found in various breeds of dogs. In humans a similar defect is caused by the Mhox gene of genes belonging to the Hox family which control the development of the final shape of the occipital bone
HOW WIDESPREAD IS IT?
Cases have been confirmed worldwide. It can be safely assumed, with the breed descending from such a small gene pool which has been repeated in/line bred the defective gene has the potential to be found in ALL Cavaliers and ALL lines. At this stage it is impossible to gauge how many Cavaliers are or have been affected with this condition. Accurate diagnosis has only been possible in the last seven years and more cases are coming to light. Unfortunately a number are still being misdiagnosed.
WHAT ARE THE SYMPTOMS?
The earliest visual symptom is that of neck & shoulder discomfort. It happens most frequently when the dog is excited or on a lead. In a very young puppy there is a reluctance to lead training, a puppy will cry out when the lead is tugged, as this action causes pain and discomfort. The term "scratching" at the shoulders is often used. As the pup becomes a little older, it will develope an odd gait as it often tries to "scratch" whilst on a lead. The dog will often cry out in pain either for no apparent reason, particularly if excited, if it has been touched or after changes in its head position. As the condition deteriorates further, the animal developes neck twisting and limb weakness. It is very distinctive and once you have seen a dog with this condition it is unmistakable.
HOW SERIOUS IS IT?
The simple answer is VERY. The condition can be so severe that the only solution for an animal in extreme pain is euthanasia. The symptoms of syringomyelia can present themselves at ANY age, and appears to take 3 main forms 1. Puppies with hydrocephlous 2. Juvenile form between the ages of 6 months to 15 months. 3. Adult form 1-10 years.
CAN SOMETHING BE DONE ABOUT IT?
Yes, with time, resources and the co-operation of all who have the good of the breed at heart. As a priority it is important to raise the awareness of this condition, as a practical step, print the article mentioned in Question 1 and send it to every Veterinary practice in your area. The sooner a dog is diagnosed and the correct medication administered the better chance an animal has of having this condition successfully managed.
IS A DNA TEST POSSIBLE?
DNA tests are available for certain conditions, but only if the responsible gene has been identified. As yet, the gene or genes associated with Syringomyelia are unkown so major expensive research is needed. Therefore a DNA test will take time, finance & the co operation of breeders. Time &finance are something the breed doesn't have. Steps to eradicate this defect need to be taken now.
http://www.cavaliers.co.uk/articles/syringohydromyelia.htm