Epilepsy in Norwich
Knowlton A. Reynders, Highwood Norwich
click here for printer friendly version
Published in Dog News, The NNT News, and Norwich
Notes and Banta
I was asked to address the topic of epilepsy and seizures
in our breed. Perhaps the best way to transmit the information
I have accumulated is to answer the most frequently asked
questions about the disease. My answers are based on the
many articles, columns, and veterinary publications I have
read. They also reflect conversations I have had with other
breeders, with owners of afflicted dogs and puppies, and
general research of cases with help from my local veterinarian.
What is Canine
Epilepsy?
In Seizures and Epilepsy in Dogs, Dr. A. Parker defines canine
epilepsy as "a state of repeated, intermittent seizures .
A seizure is an external manifestation of an intermittent massive
electrical abnormality in the brain." When one speaks to a veterinarian
about a definition of canine epilepsy, he classifies the seizures
in two categories: Those that are produced by demonstrable diseases,
best called acquired, or secondary seizures; and those seizures for
which no cause can be determined. The latter are categorized as idiopathic,
and are the most common form. Typically, they begin between the ages
of six months and five years. There is a higher incidence of idiopathic
seizures in males. An acquired seizure can be the result of such
metabolic extra cranial diseases as hepatic encephalophathy or hypoglycemia
or of such intracranial diseases as encephalitis, brain tumor, head
trauma, hydrocephalus, or neurotropic toxins -- a fancy term for
insect sprays or other poisons.
Return to the top
How
Do I Recognize a Seizure?
Any of the listed affectations can occur alone or
in combination, depending on what parts of the brain
have been involved:
 |
Behavioral changes |
 |
Disorientation |
 |
Hallucination |
 |
Hysteria |
 |
Momentary/complete loss of consciousness |
 |
Fixed expression |
 |
Stiffening or rigidity |
 |
Muscle spasms |
 |
Rapid heartbeat |
 |
Twitching |
 |
Paddling |
 |
Salivation |
 |
Urination |
 |
Defecation |
 |
Vomiting |
Speaking with owners
and breeders and my local veterinarian, I have collected
some examples of lighter
episodes: "Very
tense, tight shake. Unable to walk, although might try,
but have extended steps and are uncoordinated, sometimes
going down on rear legs or front. They do not fall over,
paw, froth, or get sick. Eyes appear wide and frightened." (From
correspondence.) "Jaw could be pried open. There
was rapid heartbeat and a body tenseness. No loss of
bladder control or defecation. The seizure lasts a minute
or two. These light seizures occur in the middle of sleep,
walking from one room to another, in the middle of an
argument--in the middle of a meal. There is no boundary
for time or place of seizure incident."
These are accepted
overviews about seizures: Dogs do not suffer during
a seizure -- their actions are involuntary;
a dog should not be moved during a seizure, except
to ensure his safety; dogs on anticonvulsant medication
enjoy a normal life expectancy; once stabilized,
some dogs can be weaned off of their medication; and, if
a
seizure lasts longer than ten minutes, call your
veterinarian immediately.
Return to the top
Are Seizures Genetic?
There was a very good article, most aptly entitled "Inheritance
and Idiopathic Canine Epilepsy", by James G. Cunningham,
DVM, PhD and George C. Farnbach, VMD, PhD, published in the
July/ August
1988 Volume of the Journal of the American Animal Hospital
Association. The article described a study that bred selectively
using epileptic
stock and traced the incidence of the disease through four
generations, watching where the epilepsy most commonly occurred.
The authors concluded "genetic mechanisms play an
important role in transmission of some and possibly most
cases of idiopathic canine epilepsy,
although the mechanism for this inheritance is not yet known.
Until the genetic
mechanisms involved are more clearly delineated, the authors
recommend that veterinarians advise owners of dogs with idiopathic
epilepsy
that 1) the idiopathic form of canine epilepsy may have a
major genetic component; 2) it generally is impossible without
considerably more
test breedings to determine the degree of involvement of
either dam or sire in producing epileptic offspring; 3) it
is unwise to breed
an epileptic dog or repeat the breeding that produced it
and it is unwise also to breed its littermates."
From my discussions with
several veterinarians, owners, and breeders, here
are some thoughts that could perhaps
benefit Norwich breeding in the future:
If a dog has a seizure of any kind, take him to the vet
for a complete
physical examination, including a blood
test. Try to determine if it was a disease-related seizure.
And
be sure to check for toxins around the
house, and have them
analyzed as well. A dog may have epilepsy
for genetic reasons or may have acquired it through a disease
--
which could itself be a genetic problem.
As a veterinarian told me, "Epilepsy is a diagnosis of elimination
-- elimination of all other causes of the seizures." If
you can find no external reason for
the seizures and they continue, you
have idiopathic epilepsy, and you
must look for its origin to your genetic
input. If you discover suspect seizures
in a bitch or dog you
are breeding
or in its background, do some serious
checking into previous breedings and
litters. Don't take chances.
The heartbreak
occurs when unknowledgeable breeders
fail to recognize danger signs, fail
to heed the concerns reflected to
them by worried owners, and continue to breed.
Since
some cases of epilepsy do not arise until the dog
is five years of age, it is understandable that a
caring breeder could unwittingly produce several litters
from an afflicted dog, with no idea that the litters
were potentially affected. But it is another thing
for a breeder who has been made aware of the problem
to make
his own determinations on the nature of the problem
-- and to continue to breed the dog.
Return to the top
What Medications are Given
for Seizures?
Dr. Parker
states "Dogs
with seizures
due to diseases
other than epilepsy
are given specific
treatment for
their disease.
They
may also be given anti-convulsants." Epileptic
dogs are treated with anticonvulsants. But
Dr. Parker further cautions, "If
the seizures are mild and occur singly and
less frequently than one every two months,
the side effects of the drug may outweigh the
benefits
of seizure control." The owner and the
veterinarian must determine the risk/benefit
component of anticonvulsant treatment. In
fact,
only 60 to 70 percent of known cases of epilepsy
are controlled. The following drugs are used
in the control of canine epilepsy:
Diphenyl hydantoin (Dilantin); primidone (Primidone,
Mylepsin); and phenobarbitol
and diazepam (Valium). And, less commonly:
Valprroic acid (Depakene); paramethadione (Paradione);
ethosuximide (Zarontin) and carbamezepine
(Tegratol). Dr. Parker also mentions progesterone's
and even indicates that acupuncture has been
used. The article goes on to list some
of the side effects, temporary or long-term,
that can accompany treatment with these anti-convulsant
drugs: Drowsiness; clumsiness;
hyper-excitability;
loss of appetite; increased thirst; and excessive urination.
Return to the top
What is Scottie Cramp?
Scottie
cramp is described in an
article entitled "'Cramp'
in Norwich" by Jean
Gledhill, appearing in
the April 1985 Dog World
Breed Notes, which I paraphrase
here: The bitch began to
manifest
symptoms at two and one-half, after her
first litter, by going
stiff in her hindquarters.
She remained conscious,
but the muscles in her
thighs were knotted and tight. I massaged
the affected muscles until
the rigidity dissipated; it took about
six minutes. She seemed
perfectly normal afterward.
Several attacks occurred
over the next few months,
and, after particularly severe attacks,
she would vomit. The veterinarian
recommended that Vitamin E and selenium
be added to her diet. I
fed
her the Vitamin E and seaweed meal, which
contains selenium, and
the incidents subsided:
One attack in the next
ten months, one further
attack eleven months after that, and then clear.
Ms Gledhill equates "Scottie cramp" to human
cramping and explains
it as the body's inability to deal with the build-up of lactic
acid in the muscles. The
human body gets rid of
the acid by sweating or urinating, allowing more oxygen to
get to the muscles. The author
notes, "It has been
suggested that Vitamin
E helps by being a transport
system for lactic acid's
removal
via urine and that the
selenium acts as a catalyst
for the removal process." Jean
Gledhill maintains a
catalogue of dogs with
this disorder. I have
found no
other documentation of this disorder in Norwich.
I hope
that, in some small
way, this article has given you some information about seizures.
I feel very strongly
that we have it,
visibly and less visibly, in many lines
of our breeding
-- old and new. In fact, no one can say with certainty that
one is entirely clear of the
problem.
The evidence strongly
suggests that idiopathic seizures are transferred genetically.
And the solution is diligently
to breed away from
any animal with a history or lineage containing suspicious
seizures. Line breeding is an
accepted practice,
and, if done carefully, has produced fabulous
Norwich. If, however,
there are seizures in the background on either side, I feel
that line breeding multiplies
the incidence of
genetic carry through. One might end up with an aesthetically
perfect dog, but in the process,
pass along to the
unsuspecting breeder or pet owner the untold miseries of
idiopathic epilepsy -- a serious
abuse
to the future of
the breed. I have tried to approach the broad issue of epilepsy
in Norwich fairly and objectively.
I hope that the
publication of what I have learned to date will help to enlighten
all of us who care about
the breed.
Information from this page cannot be used
without permission from the author.
Also see
EPILEPSY in NORWICH
An Update
Return to the top
return to home
page
|