Rhodesian Ridgeback Health
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 through the clinical examinations of the research team led by Professor Andrea Fischer and the University of Helsinki where Professor Hannes Lohi and his research team were learning the inheritance patterns of JME.
Nina Lindqvist (A Rhodesian Ridgeback breeder and Chairman of the Rhodesian Ridgeback Club of Finland) has been working hard alongside 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, however there are some cases which are more difficult to manage. As with all medications, Anti-Epileptic Drugs can carry some unfortunate side effects as the body in some cases cannot tolerate these drugs. For example, some Rhodesian Ridgebacks have suffered with lethargy, anxiety, drowsiness, 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.
(See the following chart to help you understand the inheritance patterns of JME.)
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; –
The Rhodesian Ridgeback Club of Great Britain: John Mackfall
Midlands and Northern Rhodesian Ridgeback Club: Alison Pearce
The Southern Rhodesian Ridgeback Association: Sharon Geeves
The Rhodesian Ridgeback Club of Scotland: Lisa Aitken.
As JME is a potentially fatal 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 to make sensible decisions and fully inform potential puppy owners.
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.
Alison Pearce 2017 ©
The Club strongly supports the KC/BVA Hip/Elbow dysplasia schemes and recommends that all Club members ensure all breeding stock is Hip and Elbow scored before they are bred from. The Club also asks Club members that breed or have stud dogs, that they should only breed from KC registered Rhodesian Ridgebacks which conform to the Breed Standard and are believed to be clear from hereditary defects and underlying health conditions, are mentally and physically sound and not suffering from acute nervousness or aggressive tendencies.
The Club has long held the belief that possible health problems should be acknowledged and confronted.
The breed can be affected with a condition called Dermoid Sinus (DS). This is a problem that can be detected at birth. You should be able to buy a puppy without this problem very easily. However some breeders are either ignorant of the problem or do not know how to check for it. Being told a vet has checked the litter is OK provided the vet knows about the condition and how to detect it. In the past the Club has produced a video for use by vets and breeders to help them identify the condition. If left undetected, a sinus becomes a very big problem and causes a lot of pain and suffering. What looks like a lump (which may be found and the whole area must be checked from the top of the head, along the dog’s neck /shoulder area to the base of the tail) is in fact a kind of abscess often reaching into the spinal cord. Needless to say it is excruciating for the dog. However, if detected, many Vets can now confidently and successfully operate to remove the DS and the puppy can go on to lead a happy, normal life. Do make sure that your puppy has been competently and regularly checked for DS. The Club holds a list of competent vets who have successfully operated on Dermoid Sinus affected puppies.
As far back as 1968 the Club funded a research programme at Bristol University into the incidence of Dermoid Sinus. All Club members are made aware of the condition and the importance of checking for it’s presence in newly-born puppies by at least two competent persons. In 1997 the club initiated the Dermoid Sinus Project with the ultimate objective of establishing a DNA test for the condition which could, eventually, lead to it’s elimination from the breed. The club has previously helped fund research in Sweden into Dermoid Sinus. Dr Nicolette Hilbertz of the Swedish University of Agricultural Sciences published a paper back in 2008 with her interim findings, together with our and others funding, had continued her research with amazing and unexpected results – but then due to unexpected genetic findings she experienced herself, this report has been delayed and will take more time until it is published. Hopefully, in the future she will be able to produce a long awaited genetic test for dermoid sinus. This research is cutting edge genetic research and as technology becomes more available so does the likelihood of understanding how and why a small percentage of our breed (and other ridged and non ridged breeds) are susceptible to dermoid sinus.
Although hip dysplasia is not a big problem in ridgebacks, it does occur. Hip dysplasia (HD) means that the hip bones are not fully in the sockets. This can sometimes cause a problem early on or can show up much later in a dog’s life, it is very painful to the dog and eventually they will be unable to walk. Certain families carry a higher incidence of HD than others do. Check that the parents and hopefully the grandparents of your puppy have been scored, and that they have a low score. The average for the breed is 7 for both hips, and the maximum score for any one dog is 106. The hip and elbow score of the parents is now printed on the puppy’s KC registration form; if it is not there the parents have not been scored. Breeders can come out with a variety of excuses about why they have not had their dogs checked, but since it is not expensive when you consider the price of a puppy, and can cause great distress to you the owner, as well as your dog, do not accept these excuses.
The current BVA/KC scoring scheme for hip dysplasia (HD) has been in operation since 1984 and since then over 100,000 X-rays have been assessed. Dysplasia means abnormal development, and the degree of hip dysplasia present is indicated by a score assigned to each hip.
The hip score is the sum of the points awarded for each of nine aspects of the X-rays of both hip joints. The minimum hip score is 0 and the maximum is 106 (53 for each hip). The lower the score the less the degree of hip dysplasia present. An average (or mean) score is calculated for all breeds scored under the scheme and advice for breeders is to use only breeding stock with scores well below the breed mean score.
The minimum age for hip scoring is one year, and each dog is only ever scored once under the scheme.
More and more responsible breeders are also (and have been for a number of years) have included scoring for Elbows in their breeding programmes. The current BVA/KC scoring scheme for elbow dysplasia (ED) was launched in 1998. An elbow grade is a measure of any evidence of elbow dysplasia (abnormal development). Both elbows are graded (between 0-3), but only the higher grade is used as an overall elbow grade for the dog. The lower the grade the better, with the advice given to breeders from the Kennel Club, is to ideally breed from dogs which have an elbow grade of 0.
Please visit the BVA website for more information.
Being a large breed that grows fast, some puppies can be susceptible to OCD (Osteochondrosis). This is believed to be partly inherited and partly environmental. How you rear your puppy and feed it is very important.
Any screening results received and recorded by the Kennel Club from a British Veterinary Association/Kennel Club (BVA/KC) health scheme or an official Kennel Club DNA testing scheme on KC registered dogs can be found at KC Health Tests Results Finder.