16th - 23rd May 1998 is National Epilepsy Week. Human support groups still battle the age-old superstition, fear and ignorance surrounding epilepsy against a background of low funding. The notion that epilepsy is a mental disorder is hard to eradicate and a typical human response is to pretend the condition doesn't exist. It is unsurprising therefore, that epilepsy remains a taboo subject in animals.
Imagine a dog lying on its side, its jaw wide open; perhaps there is yards of saliva on the floor, the limbs are paddling violently as if running in thin air, muscle tone is rock hard, the body is racked with convulsive movements and there may be urinary and faecal incontinence. You have just pictured a 'Grand Mal' seizure or fit.
From an owner's point of view, this is devastating enough to witness but the pain doesn't stop there. The diagnostic process may take months. There may be guilt if an owner can't afford expensive screening (Magnetic Resonance Imaging scans can cost £500) and, should medication be required, it takes more time to find the right medication in the right dose with the minimum of side effects for your dog. On top of this, well meaning friends may advise euthanasia and it is not always easy to find people who know or understand what you are going through.
A change in attitudes to epilepsy is long overdue. When epilepsy is diagnosed, a sympathetic ear and help in finding information about the condition is what is needed. A few breeders react by ignoring the dog's existence. This may be a defence mechanism from an equally devastated breeder but it only increases an owner's feeling of isolation. There may be little practical help a breeder can give, but experience has shown that the offer of information, support and concern for the dog is really valuable. Epilepsy need not be a death sentence, nor should a breeder have to wrack themselves with feelings of guilt if, out of the blue, a dog they have bred starts to fit.
Epilepsy should not be a death sentence because every dog is an individual. Fits vary in severity from Grand Mal to brief 'absences' and a Grand Mal in a Dachsie can be easier to cope with than one in a Great Dane. Fits usually only last a few minutes and for 99.9% of the time most affected dogs can lead a perfectly normal life. A dog will not even need medication if fits are mild or infrequent. In those dogs that need anticonvulsants, fits may be completely controlled or their severity alleviated and frequency decreased. Little in epilepsy is certain but so much can be achieved with the right advice and support from sympathetic veterinary surgeons and those who have been through similar experiences. Above all, based on human experience, the dog does not know what is happening to him and provided he cannot injure himself (e.g. fall down stairs) is not suffering during a fit. Many dogs with fits will die in old age of something else - if they are allowed to.
A caring breeder faced with having bred an epileptic
dog will be very distressed but there are many reasons why they should
be treated with understanding and not recrimination.
a) Epilepsy is not a disease. Fits are a symptom of an underlying problem of which hereditary epilepsy is only one possibility. Fits can be a symptom of many different physical or veterinary problems (in which case the term secondary epilepsy is used), e.g. meningitis, head injury, birth trauma, hydrocephalus, anaesthetic incident, distemper, liver disease, thyroid dysfunction, etc. etc.
b) Accurate diagnosis of fits is extremely difficult. In many cases it has to be done by exclusion. For example, a MRI scan can rule out a brain tumour, blood testing can rule out infection and a medical history can rule out trauma. There is currently no definitive test for what is known as primary (i.e. idiopathic and potentially heredity) epilepsy and any pedigree screening is only as good as the information provided to the screener, even then advice can only be based on probabilities.
c) Primary epilepsy is easily hidden so it perfectly possible for an unscrupulous person to breed from an affected animal without declaring it. Equally, until a genetic fingerprint for epilepsy (Note 1) is discovered, it is possible for a dog carrying the epilepsy gene to be bred from either knowingly or unwittingly. The consequences of such an action may not be obvious for several years.
d) The mode of inheritance in primary epilepsy is not fully understood in most breeds and research done so far suggests that many different types of inheritance are feasible e.g. simple recessive in the Keeshond, multiple recessive genes in the Golden Retriever. Given such genetic complexity, it is feasible that even the most careful breeder could unexpectedly produce epilepsy in their lines, especially in a breed with a relatively small gene pool.
e) Whether a dog fits (because of primary or secondary epilepsy) depends on his fit threshold. (The fit threshold is part of a dog's genetic makeup). A dog with a low fit threshold will fit more easily than a dog with a high fit threshold. A high threshold dog can have primary epilepsy without having a fit for several years.
f) A dog that starts to fit later in life e.g. 5 years could have been used extensively for breeding before the condition is discovered.
g) Any breed of dog can suffer from epilepsy and it is a common problem with 1 in 100 dogs affected. (Note 2)
None of this is an excuse for knowingly breeding a dog that has epilepsy and whether a potential carrier of primary epilepsy is used for breeding is governed by all the usual breeding decisions a responsible breeder has to make. For a discussion on the modes of inheritance, different types of seizures, their causes and a consideration of breeding to eliminate epilepsy, I would recommend an excellent, comprehensive paper by Todd Woods MD called "Canine Epilepsy". Dr Woods is a neurologist and Siberian Husky breeder. He shares his personal experience of planning a breeding programme in Siberian Huskies. (In one breeding experience the mode of inheritance was believed to be dominant with incomplete penetrance. Other modes are considered possible in other Siberian litters). If you are connected to the Internet look for Dr Woods web page at http://www.teleport.com/~aatuk/aatuk.htm. Otherwise, please send a large SAE plus stamps to the value of 40p to cover the cost of photocopying to Fivefold, 3 Spring Close, Great Horwood, Bucks MK17 0QU.
Membership
of the Phyllis Croft Foundation for Canine Epilepsy is open to all.
If you would like information about membership please send a large SAE
to Mrs M James, Secretary, The Phyllis Croft Foundation for Canine Epilepsy
(PCFCE), at 77 Upland Road, Billericay, Essex CM12 OLD. (£8.00
single, £10.00 joint). We regret that requests for comment
on individual cases (from veterinary neurologist Dr Croft MA PhD FRCVS)
can only be processed for members. Please spare a little time this
week to think about the many thousands of people whose lives are touched
by epilepsy, both human and canine. Help us to bring epilepsy out
of the closet. (Note 3).
Note 1
A geneticist at the University of Missouri (Columbia) is currently looking into the feasibility of researching a genetic marker for epilepsy in a family of Standard Schnauzers.
Note 2
Source:- Vétoquinol UK & University of Florida Neurology Service http://neuro.vetmed.ufl.edu
Note 3
My sincere thanks to Dr Phyllis Croft for checking
this article. Although retired for a number of years, she continues
to dedicate her life to the welfare of dogs and their owners. She
is a wonderful, caring lady to whom the Foundation will always be indebted.