Health in the Rhodesian Ridgeback
A website has been set up by the RR World Congress Health committee to help co-ordinate global research and the sharing of information. Please follow the link to view:
Juvenile Myoclonic Epilepsy in Rhodesian Ridgebacks (JME)
Juvenile Myoclonic Epilepsy in Rhodesian Ridgebacks (JME)
JME was only recognised in 2015 after extensive research was carried out at two Universities. The University of Munich research team doing clinical examinations by a led by Professor Andrea Fischer. The University of Helsinki where Hannes Lohi and his research team were learning the inheritance patterns of JME.
Nina Lindqvist (A Rhodesian Rhodesian breeder and the Chairman of the Rhodesian Ridgeback club of Finland) has been working hard along side Prof Fischer and Prof Lohi as the JME co-ordinator getting information to a Facebook page (Myoclonic Epilepsy in Rhodesian Ridgebacks) and being on hand to answer any questions.
JME is an inherited defect only in Rhodesian Ridgebacks, It is from a recessive mode of inheritance which means an Affected dog would have inherited two copies of the mutation one from each parent.
A Carrier of JME would have inherited only one copy of the mutation, from only one parent.
A dog Clear of JME obviously does not have any copies of the mutation.
The symptoms of JME are untypical to the more common Epileptic symptoms.
Symptoms of JME are frequent twitches and myoclonic muscle jerks usually when the dog is sleeping or resting.
All affected dogs have been of a young age ranging from 6 weeks to 18 months when symptoms were first noticed. Some dogs can also develop more severe tonic-clonic seizures (Grand Mal seizures) these seizures are more typical types of seizures associated with Epilepsy in general.
Photo sensitivity has also been noticed in some affected dogs. These dogs have reacted to flashing lights.
There is now a commercial test available for all Rhodesian Ridgebacks. Here in the UK we can test at Laboklin (www.laboklin.co.uk) It is just a simple blood sample or buccal swab carried out and verified by your vet.
The test will determine the JME status of your Rhodesian Ridgeback, either CLEAR, CARRIER or AFFECTED of JME.
There are treatments available which can reduce the symptoms of JME, some have even stopped the symptoms completely with very carefully managed medication. There are some cases which are trickier to manage. As with all medications, Anti-Epileptic Drugs can carry some nasty side effects as the body in some cases can not tolerate these drugs, for example some Rhodesian Ridgebacks have suffered with lethargy, anxiety, sedation, loss of co-ordination and more. It is important to monitor your dog when on any Anti-Epileptic Drugs. Vets in the UK are not all familiar with JME but Prof Andrea Fischer or Nina Linqvist are always available to discuss treatments with your vet or yourself.
If you have any questions about JME or have any other health related questions please do not hesitate to contact any of the following Breed Club Health Co-ordinators:
- Rhodesian Ridgeback Club of Scotland - Lisa Aitken
- Midlands and Northern Rhodesian Ridgeback Club - Alison Pearce
- Rhodesian Ridgeback Club of Great Britain - John Mackfall
- Southern Rhodesian Ridgeback Association - Sharon Geeves
As JME is a semi-lethal condition it is highly recommended all Rhodesian Ridgebacks to be used in a breeding program are tested. Knowing the JME status of your RR's you wish to breed from will help breeders make sensible decisions.
Breeding two clear dogs can not produce any affected or carrier puppies.
Breeding a clear dog to a carrier dog can not produce any affected puppies, therefore a suitable carrier RR should not be ruled out of any breeding programmes but should never be bred to another carrier as affected puppies will almost certainly be produced.
Affected animals should never be used in breeding.
See the chart below for a better understanding of the inheritance pattern of JME;
EOAD - Early Onset Adult Deafness
An inherited deafness clinically documented among purebred dogs of the Rhodesian Ridgeback breed. Affected dogs appear to show normal hearing early in post-natal development, but ultimately these dogs lose their hearing, often with complete loss by 1 year of age.
Research in Dr. Neff’s lab has established that the genetic mode of transmission from parent to offspring follows a simple Mendelian autosomal recessive pattern of inheritance. This means that any sire or dam that has previously produced affected progeny must be a carrier of the causal mutation.
Follow this link for information on testing, the code is liondog :
Degenerative Myelopathy (DM)
Dermoid Sinus (DS)
Dermoid sinus is a neural tube defect that is estimated to affect around 4% of Rhodesian Ridgeback puppies born globally. It is now widely accepted that DS can be operated and removed when the puppy is around 8 weeks of age by a skilled Veterinarian. The puppy should not be bred from and should be castrated/spayed at the appropriate age but otherwise will lead a normal life. If the DS is not removed it will become infected which will result in pain, swelling and possibly further complications. It should be noted that normal, unaffected parents can still produce DS affected off-spring.
Dermoid Sinus, if present. will be found along the dorsal mid-line - including the tail and the top of the hear between the ears. There can be a single or multiple, and they are viewed as a tiny opening on the skin, like a small mole to look at. On shaving the region it will become apparent that a DS is there. Puppies with DS are born with it - it's not something that will develop as the pup ages, it may get infected but it will always have been present as it is a birth defect.
Puppies should be checked by multiple breeders/owners/veterinarians who have experienced the condition as it can be difficult to spot on some. For advice on how to check please contact us.
There is still research on-going as to the cause and genetic link of DS but at this time it is unknown. There was a thought that the Ridge may be to blame, but as DS is found in many other breeds as well as Ridgeless Ridgebacks this has yet to be proven.
There is a lot of information on Dermoid Sinus on the internet, please follow the links below to read more:
Info from RR Club of the United States:
A research study into inherritance:
Folic Acid study -