PRA-prcd test.

Another test has been available for Vizsla for little while and I am now plodding through all the dogs having them done.  

Results first for Willow as she is pregnant.   I am thrilled to tell you she is clear, and can not pass this to her offspring as she does not carry the gene for it.  So super thrilled as PRA is vile. 

I am going to next do Maverick, followed by others.   So watch this space.  

We go the extra mile because we care.  We go the extra mile because we want you as our puppy owners to have assurance.  We go the extra mile because we do not like to think of dogs we have bred with eye issues.  

Please also note I need to write an article on dry eye condition which has affected hundreds of dogs across the UK due to buckwheat in the diet.  I will get around to this. 

So what is it?  


PRA-prcd in Dogs: Causes, Symptoms, Testing, and What Owners Need to KnowProgressive retinal atrophy, or PRA, is a group of inherited eye diseases that gradually cause vision loss in dogs. One specific form is progressive rod-cone degeneration, commonly abbreviated PRA-prcd.
Although PRA-prcd is not painful, it can significantly affect a dog’s quality of life. The good news is that many dogs adapt remarkably well to gradual vision loss, especially when their environment and daily routine remain consistent. Genetic testing also allows responsible breeders to reduce the risk of producing affected puppies.

What Is PRA-prcd?PRA-prcd is an inherited degenerative disease affecting the retina—the light-sensitive layer at the back of the eye.
The retina contains two main types of photoreceptor cells:

• Rods, which help with vision in dim light and at night
• Cones, which support daylight vision and color perception

In dogs with PRA-prcd, rod cells typically deteriorate first, followed by cone cells. As the disease progresses, the dog develops worsening night blindness and eventually loses much or all of its daytime vision.

PRA-prcd is caused by a mutation in the PRCD gene. It is inherited in an autosomal recessive pattern, meaning a dog generally must inherit two copies of the disease-associated variant—one from each parent—to be at risk of developing the condition.

Which Dog Breeds Can Develop PRA-prcd?
ANY dog breed can develop it. 

The PRA-prcd variant has been identified in many breeds and mixed-breed dogs. It is especially relevant in certain lines of:

• Labrador Retrievers
• Golden Retrievers
• American Cocker Spaniels
• English Cocker Spaniels
• Miniature and Toy Poodles
• Portuguese Water Dogs
• Australian Cattle Dogs
• Chinese Cresteds
• American Eskimo Dogs
• Finnish Lapphunds
• Chesapeake Bay Retrievers
• Nova Scotia Duck Tolling Retrievers

This is not a complete list, and the presence of a breed-related risk does not mean every dog in that breed will develop PRA-prcd. Other forms of PRA can also occur, sometimes due to entirely different genetic mutations.
Signs and Symptoms of PRA-prcdPRA-prcd usually develops gradually. The age at which signs appear can vary considerably depending on the dog’s breed, genetics, and individual health.
Early signs may include:

• Reluctance to go outside or move around in dim light
• Hesitation on stairs or in unfamiliar areas
• Bumping into objects at night
• Difficulty finding toys in low light
• Increased dependence on familiar routes or people
• Dilated pupils or an unusual eye shine

As the disease advances, owners may notice:

• Poor vision during the day
• Bumping into furniture or walls
• Difficulty navigating unfamiliar environments
• Less interest in visually guided activities
• Cloudiness in the eyes caused by cataracts

Some dogs develop cataracts as a secondary effect of retinal degeneration. Cataracts can make the eyes appear cloudy and may occasionally lead to painful complications, such as inflammation or glaucoma. A dog showing signs of eye discomfort should be examined promptly by a veterinarian.
Is PRA-prcd Painful?PRA-prcd itself is generally not painful. However, complications such as cataracts, inflammation, or glaucoma can cause discomfort.
Dogs may not always show obvious signs of eye pain, so changes such as squinting, redness, excessive tearing, rubbing at the eyes, or sudden worsening of vision should be evaluated by a veterinary professional.
How Is PRA-prcd Diagnosed?Diagnosis usually involves a combination of the dog’s history, an eye examination, and genetic testing.
Veterinary eye examinationA veterinarian or veterinary ophthalmologist may examine the retina for characteristic changes, including:

• Abnormal retinal pigmentation
• Narrowing of retinal blood vessels
• Changes to the optic nerve
• Increased reflection from the back of the eye

An instrument called an electroretinogram, or ERG, may be used to measure the electrical responses of the retina. This can help detect retinal dysfunction before changes are obvious during a routine examination.
DNA testingA DNA test can identify whether a dog has:

• Two normal copies of the tested gene variant
• One normal copy and one disease-associated copy
• Two copies of the disease-associated variant

It is important to understand that a DNA test for PRA-prcd detects a specific genetic variant. A clear result does not rule out every possible form of PRA or every inherited eye disease. Breeders should choose tests appropriate to the breed and bloodline and discuss results with a veterinarian, genetic testing laboratory, or breed health specialist.
Understanding PRA-prcd Genetic Test ResultsBecause PRA-prcd is usually autosomal recessive, test results are commonly described as follows:
ClearThe dog does not carry the tested PRA-prcd variant and is not expected to develop PRA-prcd caused by that variant or pass it to its puppies.
CarrierThe dog carries one copy of the variant but is generally not expected to develop PRA-prcd from that variant. A carrier can pass the variant to its puppies.
AffectedThe dog carries two copies of the variant and is at risk of developing PRA-prcd. Clinical signs and the age of onset may vary.
A carrier is not an unhealthy or undesirable dog. Responsible breeding programs can safely include carriers by mating them with clear dogs, followed by appropriate testing of offspring. Removing all carriers from a breeding population at once can unnecessarily reduce genetic diversity.
Is There a Cure for PRA-prcd?At present, there is no widely available cure that reverses the retinal degeneration caused by PRA-prcd. Treatment focuses on:

• Monitoring the eyes for cataracts and glaucoma
• Managing any inflammation or discomfort
• Keeping the home environment predictable
• Preventing falls and other injuries
• Helping the dog adjust to reduced vision

Many dogs with gradual vision loss continue to enjoy a good quality of life. Dogs rely heavily on their sense of smell and hearing, and they often learn to navigate familiar spaces successfully.
Helping a Dog Adjust to Vision LossIf your dog is losing vision, a few practical changes can make a major difference:

• Keep furniture, food bowls, and beds in consistent locations.
• Use baby gates near stairs or other hazards.
• Block access to swimming pools and unsafe outdoor areas.
• Keep your dog on a leash in unfamiliar places.
• Use verbal cues before touching or approaching the dog.
• Avoid leaving objects in walkways.
• Consider textured mats or scent markers to identify important areas.
• Introduce changes gradually.
• Maintain a calm, predictable routine.

It is important not to assume that a blind or visually impaired dog cannot enjoy walks, play, training, or social interaction. Activities that use scent, hearing, and touch can be especially rewarding.
Breeding and Preventing PRA-prcdGenetic testing is one of the most effective tools for reducing PRA-prcd in future generations. Breeders should test potential breeding dogs before mating and interpret results carefully.
A common approach is to avoid breeding affected dogs and to pair carriers only with clear dogs when there is a sound reason to preserve valuable genetics. Puppies from carrier-to-clear matings should be tested or managed appropriately before being used for breeding.
DNA testing should be combined with regular eye examinations and a broader health program. A dog can test clear for PRA-prcd and still carry another inherited eye disease or develop an unrelated eye condition.
When Should You Contact a Veterinarian?Arrange a veterinary examination if your dog:

• Has difficulty seeing at night
• Bumps into objects
• Hesitates on stairs
• Develops cloudy eyes
• Squints or rubs its eyes
• Has red or watery eyes
• Experiences sudden vision loss
• Comes from a breed or family line known to carry PRA-prcd

Early assessment can help confirm the cause of vision changes and identify complications that may require treatment.
Final ThoughtsPRA-prcd is an inherited retinal disease that can gradually lead to blindness, but it does not necessarily prevent a dog from living a happy and active life. Early recognition, veterinary monitoring, environmental adjustments, and appropriate genetic testing can all help.
For breeders, DNA testing provides valuable information for making responsible mating decisions. For owners, understanding the condition can make it easier to support a dog as its vision changes.

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This article is for general educational purposes and is not a substitute for advice from a veterinarian or veterinary ophthalmologist.