The health of
our dogs is our top priority. We hope that
the information on these pages can aid you
in the care of your Border Collie.
Neuronal Ceroid Lipofuscinosis (C.L)
Hip Dysplasia (H.D)
Collie Eye Anomaly / Choroidal Hypoplasia (CEA)
Links to Other
Sites:
What Vaccines Should My Dog Receive and How
Often? -
written by Ron
Hines DVM PhD
What Should I Feed My Dog? -
written by Ron
Hines DVM PhD
More on OCD -
written by
Debbie Brooks DVM
C.L. is a
disease that affects the cells of the body,
and in particular the nerve cells. C.L. is
not contagious but it is inherited by a
simple recessive gene in the same way that
coat colour is inherited. The disease will
only manifest itself in dogs which have
inherited the recessive gene from both
parents. Other offspring of a litter
containing an affected dog can either be
carriers or clear.
C.L. is
characterised by the accumulation of ceroid
lipofuscin, a waxlike lipid waste product of
cell metabolism. This substance accumulates
in the tissue cells of the body. In the
brain there is limited room for storage of
waste products and, as an estimate, at
somewhere between 18 and 22 months of age,
sufficient waste product has accumulated to
begin compressing and destroying healthy
brain cells. At this time the dogs display
changes in behaviour, deteriorate rapidly
and are usually euthanased. Confirmation of
the disease is performed by brain biopsy.
This can also be used to identify affected
pups at approximately 7 months of age.
Further research is needed to develop a DNA
test to identify carrier animals.
There have been
approximately 36 cases in Australia of C.L.
affected (clinically proven) Border Collies
since the first case was diagnosed in 1980.
When compared with the number of puppies
produced during this time, it can be seen
that this disease is very rare in the
breed. Carrier dogs can only be identified
when they have produced affected offspring
and the owners have given permission for the
details to be published. There are other
carrier dogs in the gene pool but as yet
these have not produced affected offspring
and therefore are not known at his time.
There are some known carriers whose owners
have not permitted the dogs' name to be
published.
Prospective
breeders of Border Collies should be aware
of the need for very careful selection of
breeding animals to ensure that known
carriers are not mated together. The
majority of Border Collies today will have
known carriers in a seven-generation
pedigree. However when you have this
information you can make decisions to ensure
that you have one parent with relatively
clear lines, or a small number of carriers
well back in the pedigree of both sire and
dam.
Research
continues at the University of New South
Wales to locate the gene responsible for the
disease so that puppies and adult dogs can
be screened for the disease and determine if
they are carriers or clear. The State Breed
Clubs raise funds and donate it to assist
funding this ongoing research.
Unlike other
breeds the Border Collie does not usually
show physical signs of H.D. Border Collies
can appear normal and have good movement,
but on examination by x-ray clearly show
that they are affected by H.D. to varying
degrees. Border Collie breeders have been
known to say that their lines are clear and
that they have no problem with H.D. but
unless they have all their breeding stock
x-rayed and scored, this statement may not
be true. If breeders have been scoring all
breeding stock an offspring for many
generations and the scores are low, for
example less then 5, then they may consider
that they have a reduced chance of producing
a severely affected animal.
All breeders at
a minium should x-ray all breeding stock and
submit all films for scoring. The
importance of submitting all x-rays for
scoring, no matter how bad they appear, is
to get a true breed average. What has
happened in the past is that x-rays that
definitely show a moderate to severe problem
are not necessarily submitted for scoring
and therefore the score is not included in
the data. We therefore end up with a breed
average that is not necessarily a true
reflection of the degree to which Border
Collies are affected by HD.
For example you
have a dog that has received a total score
of 13 but because only moderately affected
dogs' x-rays have been submitted for scoring
the breed average is 9, and therefore your
dog may not be recommended for breeding
because it exceeds the breed average.
However if all x-rays were submitted the
breed average may be 15 and therefore your
dog would be suitable for breeding. The
more Border Collies that are x-rayed and
scored the better idea we have concerning
this disease and the less likely it is that
we will breed affected animals, and so
improve the breed overall. Other breeds are
undertaking such control measures through
their club regulations.
CEA refers to an
inherited abnormality in the development of
the retina, optic nerve and choroid. These
are all structures at the back of the eye
involved with vision. CEA is a multigenetic
trait, is present at birth and does not
change with age. If is strongly recommended
that puppies 6 to 10 weeks are tested for
CEA by a specialist eye vet
(ophthalmologist). There are varying
degrees of abnormality with CEA. It can
affect one eye or both; from a mild case
where vision may be reduced, to severe CEA
with retinal detachment and total loss of
vision.
Just because an
animal is mildly affected, one cannot assume
that progeny will not have a sever case.
The same may be said of dogs that hold clear
eye certificates. They may carry CEA, and
produce carrier or affected offspring. To
produce affected offspring both parents must
either be carriers or affected.
Testing for CEA
and other eye disorders involves no pain.
It is performed using eye drops that dilate
the pupil so that the ophthalmologist can
examine the eye. Annual eye examinations
are recommended to detect any abnormalities
or the eye, but testing for CEA is only
required once.
These two
diseases are becoming more apparent in the
Border Collie. Both require further
research into their causes, diagnosis,
management and their impact on the breed.
TNS was recognised in Border Collies about 8
years ago in New Zealand and Australia.
Puppies aged between 6 weeks and 7 months
have a range of symptoms including lameness,
chronic diarrhoea, fevers and loss of
appetite. The pups also persistent bone and
gastrointestinal infections. The bone
marrow of the affected dogs identifies that
neutrophils are not released into the
circulation. Consequently, the bone marrow
becomes clogged with neutrophils - a state
called myelokathexis. It is thought the
condition has a genetic basis, as there
seems to be some familial correlation in the
pedigrees of affected dogs.
OCD is a
degenerative disease involving the joint
bone and cartilage. It is characterised by
partial or complete detachment of a fragment
of bone. It is caused by the interaction of
a number of factors including a genetic
predisposition as well as environmental
conditions eg. over-supplementation.
