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Progressive Retinal Atrophy (PRA) In Dogs:
Progressive Retinal Atrophy (PRA) In Dogs:
The retina is at the back of the eye. It is composed of highly
specialized nerve cells that receive light impulses. The retina
passes on a message to the brain as nerve impulses.
In progressive retinal atrophy, there is a gradually wasting
or thinning of the dog's retina, so that sight is lost. It is an
inherited condition and is incurable. Although PRA has been
eliminated in some breeds, generally speaking the incidence of PRA is
increasing.
The main difficulty with controlling this serious condition is that in
some breeds of dog, it only becomes apparent when the dog is several
years old and by that time the dog may have produced many pups.
In PRA-affected Miniature and Toy Poodles, for example, night blindness
is present between 2-4 years of age, and day blindness between about
5-8 years.
What Are The Signs Of PRA in dogs?
At first, the dog may be unwilling to go out at night. He may
appear to be "afraid" of the dark, stays close to you at night and
appears "short-sighted". Little signs such as stumbling while
going down stairs, or going much more slowly than before, can be
indications of failing sight. In Miniature and Toy Poodles and
Irish Setters, sight at night always goes first, progressing to
blindness even in the daylight. All dogs affected by PRA go blind
if they live long enough. There is an instrument called an
electroretinograph which can be used to detect early PRA before it is
otherwise present and this instrument can be useful in selecting
breeding stock.
What Breeds Of Dog Are Affected?
Any breed can be affected.
At What Age Can You Be Sure Dogs Do Not Have PRA?
A veterinary ophthalmologist must examine the back of the eye with
specialized equipment. The earliest one can be certain with most
breeds of dog is 5 years of age, but with some breeds the specialist
can certify freedom from the disorder as early as 3 years.
Is There Any Treatment For PRA?
No. Sometimes complications such as cataracts and glaucoma set in
and they may have to be managed to reduce inflammation or pain.
How Can PRA be eliminated?
The only way to eliminate the condition is to avoid breeding from carriers of PRA or from affected dogs.