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American Miniature Schnauzer
Club, Inc. |
from the AMSC Health Committee
Errolyn Martin, Gwen Mulheron, and Vera Potiker
Canine Eye Registration Foundation (CERF) annual reports indicate that many of us are not having our puppies’ eyes examined. There are many reasons why some breeders do not make puppy eye exams a routine part of their breeding program. Our job is to help breeders understand why these exams are very important, not only to the individual breeder but to the breed as a whole.
Let’s first address congenital cataracts and the
somewhat popular belief that it is a problem of the past. Perhaps this defect was eliminated from
our gene pool by the dedicated efforts of the breeders who were willing to
test-breed away from the problem in the not-so-distant past. Certainly, their efforts at least
greatly reduced the frequency of the gene in the gene pool. Statistically, it is almost impossible
to completely eradicate a recessive gene from a population without a DNA
test. Breeders can help reduce the risk
of this problem resurfacing and spreading before being noticed - by having
puppy eye exams.
Recently there have been reports of unilateral and bilateral
cataracts in young adult dogs. It
is unclear at this time whether these “juvenile” cataracts are
diagnostically distinguishable from congenital cataracts. Juvenile cataracts are thought to sometimes
develop in one eye and later develop in the other eye. For a dog with a unilateral cataract,
the issue is confusing enough. But
for an adult dog with bilateral cataracts, that has not had a puppy eye exam,
getting an accurate diagnosis can be a lengthy and costly process. Breeders can help prevent misdiagnosis, save
time and money, and know what defect they are dealing with - by having puppy
eye exams.
Now consider that there are other eye defects that occur in
our breed. At the Oct, 2001 AMSC Board
meeting, Catherine McMillan brought to our attention the issue of retinal
dysplasia. This defect is known to
be inherited in several other breeds and evidence provided to the AMSC Health
Committee suggests this may be the case in our breed as well. Retinal dysplasia can be found in three
forms: retinal folds, geographic dysplasia, and retinal detachment. The defect results in varying degrees of
vision loss with detachment resulting in blindness. All three forms can occur in the same
litter. Folds may be mild to
severe, with mild folds appearing to improve with age. A puppy with mild folds may have a
normal adult eye exam, so without a puppy exam the breeder might never be aware
of the problem. It is possible that
a more severely affected puppy might not act suspiciously, as puppies with
vision impairment often adapt to their surroundings and/or follow their
littermates to navigate their environment.
The earliest indication that there might be a problem could occur when
the puppy goes to his new home and he no longer has the security of his
littermates or familiar surroundings.
Unfortunately, this is when the defect becomes the buyer’s
problem. The breeders
currently working to uncover the genetics of retinal dysplasia have commented
that had they not been performing routine puppy eye exams this problem might
have gone unnoticed for some time.
Their discovery was not based on a suspicious puppy, but on routine eye
exam results. Breeders can more easily identify
a potential problem before it becomes a larger problem - by having puppy eye
exams.
What about CERF? If you cannot get CERF exams, get exams performed by a veterinary ophthalmologist, preferably board certified. CERF exams help the organization gather important statistical information, but getting the exam is most important. If you do get CERF exams, you don’t have to send your form in if you choose not to. The ophthalmologist automatically sends in a statistical copy, so the stats are recorded with CERF but the individual dog is not. If you want to send in your individual CERF form and have the dog registered there are advantages, such as the CERF number appearing on registration forms and the dog's exam recorded in the AKC Awards publication.
There are several other eye anomalies that are monitored by CERF statistically. Although currently their incidence may not be significant, tracking of these defects is very important as an upswing in the number of reportable cases of a defect might assist CERF in investigation of the problem. In addition, scientists and researchers sometimes use statistical information from databases to identify health issues within and across breeds for potential research opportunities.
Try to get exams done anywhere from 8-12 weeks of age. From a statistical position, show and pet puppies alike should have an eye exam if possible. Breeders should consider the information they may gain when deciding whether or not to examine all puppies. For example, a litter of five pups is evaluated and two are kept as show prospects. If the three pet pups don’t have an exam, that amounts to 60% of the litter for which no basic information is known. If even one of the three pets had been examined and found to have an irregularity, the breeder would know to watch for this problem. If even one of the three had been diagnosed with an inherited disorder, the breeder would have been able to advise the buyer as to the condition and, more importantly, determine the ancestors’ and the two show puppies’ risk for being carriers and breed away from the problem in their breeding program.
Special Note: The 8-12 week exam age is recommended for routine exams. Several ophthalmologists recommend this age range. Exams before eight weeks of age can be more difficult due to size of the eye, and results can be ambiguous due to developmental issues. If you are dealing with a particular eye issue in your breeding program, please consult your VO for optimum exam age.
If you have questions regarding eye exams you can contact:
Canine Eye Registration Foundation - http://www.vmdb.org/cerf.html
You can also find links to ACVO Diplomates and Eye Clinics
in the
Copyright 2003.
American Miniature Schnauzer Club, Inc. All rights reserved.
Revised March 27, 2005