Progressive retinal atrophy (PRA) any experience?

Cuffey

Cuffey

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A friend is asking for any info--ie what did owners notice before a diagnosis was made.
Her dog is a rescue, born deaf, works on hand signals so his sight is particularly important

Any experience anyone please?
 
Plenty of experience including working towards genetic markers.

What breed as there are several forms which can have different progression rates?

PM if you prefer.
 
You will notice in certain lights that the eye reflects light back at you.It depends if it is early onset,more rapid sigtloss,or the later sort.I have a lab with it,from eye tested clear parents...but it is a recessive gene,so obviously both parents were carriers.lesson learnt though,my girls are now DNA clear tested,and my new lab puppy boy is DNA clear by parentage.It would seem that the stock phrase "eye tested parents" does not mean a lot.The eye specialist stated it is quite rare to get affecteds in labs...oh well,trust me!But I would recognise it now anywhere.
 
Is PRA the same thing as "Collie Eye"? I've googled it, and from what I can see, the article on C.E. only refers to Rough (Scotch) Collies, and their short coated counterparts.

C.E. is also evident in working sheep dogs, though they didn't seem to be mentioned, or not that I could see.

When I was seriously into gun dogs in the '70s, it was usual that the show bench were blamed for everything! That can't have been right, because they've had virtually no effect upon work dogs.

The heritable diseases and problems since the '70s, and we were well aware then of HD, have become much worse; spaniels and their elbows being one example. What on earth are we doing which is so wrong? The breeds which we keep today have evolved, is it not time that breed societies and the Kennel Club recognise that health testing, though a useful tool in the battle against ill health, isn't the only answer? Is it not time for the genetics of our canines to be adjusted, strengthened and improved, by the careful inclusion of out crossing to other and similar breeds?

It seems to me that the current list of health problems which effect our dogs today is growing and worsening. If we can't stem the tide, then disaster looms for many breeds, I fear.

Alec.
 
Alec,
PRA & CEA are not the same.
Why are we seeing more problems? Some are known to be recent mutations and as such are unique to one breed (eg PRA in Glen of Imaals whiich differs from all other variations and thankfully now has a genetic test) also dogs are not being tested in the same way.

Dogs used to have a working life prior to breeding - particularly collies & gundogs whereas no they are often bred from at an earlier age before problems become apparent.
Cross breeds are throwing up all sorts of inherited problems. The mutt breeders make a big show of having a DNA tested parent so the pups can't have X & ignore Y, Z, A,B .....

A bit of light reading ;-
http://www.bva.co.uk/public/documents/Eye_Leaflet.pdf

At the last test session I help at the only affected dog was an unpapered border collie. His eyes were green and at 2 he had sired several litters. Totally blind and his owners were asking if the son that they had kept was ok to breed from.
 
Thank you guys, it is my dog that is under question. Just trying to get to the bottom of some concerning behaviours, it is more and more apparent to me that his sight is not right, but clarifying what it could be is a challenge. Obviously I am working with the vet, but just doing some research of my own as well and PRA sounded so spot on, I wanted some anecdotes to compare with.

I think there are many reasons for increasing health problems, including issues with breeding, but there are also many more dogs staying alive than there were, and being diagnosed better instead of PTS at birth. Certainly within the deaf dog world we have far more litters being given a chance, whereas over the years they have been hushed up because they are just PTS at birth or soon after.
 
s4sugar,

thank you for that. I'm amazed that there are breed specific strains or certain mutations, of known heritable diseases. Would I be right in saying, specifically with those breeds which are of numerically low populations, that only breeding from health tested parents would bring about it's own risks, considering the vastly reduced gene pool?

If I am right, then where do you see the answer? I'd be interested to hear from anyone who has sensible solutions to the problems.

Alec.
 
Pip our Lancashire Heeler is a carrier of PLL, she was DNA tested and we were given the certificate on purchase. If we bred from her she would only go to a stud who was clear, as a breed on the vunerable list only breedng clear to clear would dramatically reduce the gene pool and would come with its own problems.

Unfortunately as a vunerable breed there are breeders out there who are not eye testing and are breeding from known lines with eye problems and are selling for the same or more than responsibley health tested breeders. Never more is it more important for prospective puppy buyers to do their research.
 
Alec Swan said:
The breeds which we keep today have evolved, is it not time that breed societies and the Kennel Club recognise that health testing, though a useful tool in the battle against ill health, isn't the only answer? Is it not time for the genetics of our canines to be adjusted, strengthened and improved, by the careful inclusion of out crossing to other and similar breeds?

It seems to me that the current list of health problems which effect our dogs today is growing and worsening. If we can't stem the tide, then disaster looms for many breeds, I fear.

Alec.
Click to expand...

But the health testing means and DNA registering means that problem lines/genes can be bred away from?

Are there actually more problems, or more reporting/more awareness/more testing?
 
Like dobiegirls Pip, our heeler is a carrier of PLL, tested before we had him. My daughter made the decision to castrate him because an entire dog would have been difficult for her to take to work with her. Had he been a bitch of suitable quality, we might have considered a litter, to a clear dog just because of the small gene pool in the breed.

dollyanna, I have no experience of PRA but my old GSD did have some sight issues. I became aware that she was tripping up and down steps, having trouble sometimes gauging gaps in doorways, and if you threw a ball any distance she had no idea where it had gone. My vet checked her out thoroughly, and referred her to a specialist eye hospital. After many tests the conclusion was that there was no problem with her eyes, so the likelihood it was the signal not been sent from eye to brain or vice versa (that was how it was explained to me in laymans terms). Possibile cause was some sort of tumour, however the only way to confirm this was an mri scan and although we would have got a diagnosis, surgery wasn't an option. So we just left and hoped the deterioration wouldn't be too fast. In fact although her eyesight did worsen it was very gradual and she coped well for 3 or 4 years, it was only when her worsening sight was combined with a deterioration in a spinal condition that we made the decision to pts.
That has probably been of no use to you, but your mention of concerning behaviours just rang a bell, if your vet is not able to determine the problem it might be worse asking for a referral, as long as you have deep pockes (or insurance).
 
Miniature Bull Terriers suffered from PLL as do Lancashire Heelers,we were lucky,because the AHT@KC allowed us to interbreed ..subject to rigorous health tests to get permission,so we were able to "tread water" until the DNA marker was found.Basically,the big bull terrier does NOT have PLL in it`s genes at all,so by mating a mini bull to a bull terrier it was impossible to produce an affected .However,it was found that while these interbred animals were always ok,it only took a couple more generations for the gene to reappear.Finding the Marker for PLL took some eight years,with the AHT running in competition with an American facility ,neck and neck.All of us in the breed sent in DNA swabs galore,and raised a lot of money for this,the strange thing is that both facilities found the marker at more or less the same time!Since then there are very few breeders,in fact I can only think of one,who do not know the DNA status of every breeding dog they own.
The relief of being on top of this one major defect in my breed really cannot be imagined.Once we sold puppies in the hope they would not be affected,and no good dog breeder wants heartbroken owners three years down the line.About fifteen years ago it was found that the eye drops used in Glaucoma in humans, Xalatan, worked well in minis whose eyes had lens "on the wobble" this at least meant blindness was`nt the threat it had been.However,it meant every owner going for an eye check six monthly from the time the dog was 2 1/2 years old.Pet owners are not always so commited.PLL is horrible in that it strikes between the ages of around three and seven,after seven the dog is ok.Now that meant of course that it was likely a good one would have been bred from already,before the defect became noticeable.
Now we have the DNA it is possible to breed it out,although to only use clears is a way of reducing the gene pool,so personally my carriers go to clears,sometimes clears to clears,depends always on the most suited dog for that bitch.And,sometimes I will inject some completely new blood by using a small bull terrier ..under license from the KC
The use of science in dog breeding is a whole new brave world,whilst I know thee are bad eggs a lot of us are dedicated to producing the very best ,healthiest of our breed possible.
 
I hope everything goes as well as possible with your dog Dollyanna.



About the breeding I want to add that there is today several dog breeds who can check for some inherited diseases by using DNA-test, but for example with PRA, we first have to know if the breed is carrying the gene for prcd-PRA or rcd2-PRA or rcd3-PRA or Dominant PRA ...

It also isn't as "easy" as the breeders just saying that in our dog breed we will only breed puppies where both parents are known non carrier for this or that disease. Because I've read that they've already tried that in the eighties in the Basenji breed, and it didn't end completely successful.


As I recall it, note that it was some years since I read this, Basenjis could have a liver disease, however the veterinarians could simply do some test on the liver, and even though I don't know if the test actually involved DNA-testing, the result of the test was the same as today's DNA-test, and showed whether the dog was clear, if it was a gene carrier or had the disease.

Then some very influential breeder/breeders decided that they should only breed Basenjis with a clear result, thereby excluding not only Basenjis with liver disease from breeding but also those Basenjis who was gene carriers. The problem is that even with today's DNA-tests, a clear result only applies to the specific disease that you have tested for, and the dog can very well carry the gene for another disease.

But the influential Basenji breeders didn't think about that, they were on a crusade to eradicate the liver disease and by only using the clear tested Basenjis in their breeding, as I recall it, they succeeded.


However it also meant a big difference in the number of Basenjis that was available to be used in breeding and suddenly it turned out that a few Basenjis had been carrying a gene for another disease, before with the larger number of possible breeding animals, the risk for that you should happen to breed two of those few Basenjis to each other was very slim. Now since they unfortunately were among the Basenjis to have a clear liver test the gene for Fanconi syndrome, which can cause kidney failure, spread like wildfire through the breed.

Up until only a few years ago, there was no test available that could tell whether a Basenji was a carrier of the gene for Fanconi syndrome or not, and even now the test that does exist only seem to be able to give probable results, as in probably clear, probably gene carrier etc.
Maybe I'm making a wrong assumption, but to me the use of the word probable makes it sound as if there is actually, hopefully only very small but still, risk that a Basenji with a probably clear result, could turn out to be gene carrier.



Anyhow, as I understand it, the risk involved with narrowing the gene pool is the reason for why the Swedish Kennelklubben mostly have chosen to say, that breeds that have a disease where DNA-test is available, should only exclude the dogs with affected test result from breeding.

So to use Finnish Lapphund as an example, if I want to breed there is the following options :
* Both parents have clear prcd-PRA result = all the puppies will be clear and no puppies can develop prcd-PRA.
* One parent have a clear prcd-PRA test and the other is either a gene carrier or not tested = some of the puppies will be clear, some puppies might be gene carriers and no puppies can develop prcd-PRA.


But as I understand it, and to make it even more complicated, even a Finnish Lapphund with a clear prcd-PRA test result can still as it gets old, develop a non inherited old age cataract that comes simply from bad luck and having lived long.


 
Talking of Basenjis...do any fans of these know what hereditary diseases they suffer? Heard a rumour the LAD..Lethal Acrodrmititus has been found in some,this causes dwarfism and skin probs esp on the feety..anyone in the know?
 
My "Quote" button wont work, so posted by CaveCanem;

"But the health testing means and DNA registering means that problem lines/genes can be bred away from?"

I agree with you but then depending upon how exclusive or selective we are to be, when choosing to breed, and especially with the breeds which are numerically challenged, to start with, then we reduce the available gene pool EVEN FURTHER, and that in itself, will exacerbate the problem.

With GSDs, for instance, the world wide gene pool is massive, and there is no earthly reason why, by testing and being selective, we shouldn't see the improvements which we do, but if we consider Great Danes, Deerhounds and Wolfhounds, by selecting through an already shrunken gene supply can only make matters worse.

I remember the first Lancashire Heeler that I saw, back in the early '80s, and what a super little thing it was. Then I saw more, as they became more popular, and every single one of them, was a delight. I may well be wrong, but at the time, they either weren't, or had only just been recognised by the KC. What has gone so wrong for them, where we now have a breed which has grown to achieve problems which simply didn't exist previously? We knew enough about heritable problems in certain breeds THEN, so how have we created the problem? Is it simply a case of a breed becoming popular and a case of over breeding?

It's all very sad, and I suspect that there are those who fiddled whilst Rome burnt.

Alec.
 
EAST KENT said:
Talking of Basenjis...do any fans of these know what hereditary diseases they suffer? Heard a rumour the LAD..Lethal Acrodrmititus has been found in some,this causes dwarfism and skin probs esp on the feety..anyone in the know?
Click to expand...

I haven't found anything about that disease in connection to Basenjis in Sweden, however the breedclub in Sweden do have a list with other diseases that they know have occured either in Sweden or abroad :

*"Basenji retinopathy" (a new disease that haven't got a proper name yet, but they've found out that Basenjis can have this eye disease that resembles PRA but it isn't quite the same).

*Coloboma (some sort of a hole in one of the structures of the eye).

*Epilepsy.

*Fanconi syndrome (can cause kidney failure).

*Furunculosis (seems to be a sort of "paw furunculosis", I hope that makes sense).

*Hip dysplasia.

*Hypothyroidism (thyroid gland doesn't make enough thyroid hormone).

*Immunoproliferative enteropathy (also called Malabsorption, an autoimmune intestinal disease).

*Inguinal hernia.

*Pancreatic insufficiency (lack of digestive enzymes).

*Persistent pupillary membrane (involves the lens in the eye and remnants of a fetal membrane).

*Progressive retinal atrophy.

*Pyruvate kinase deficiency (involves enzyme and decreased red blood cells).

*Umbilical hernia.


And a disease that I don't seem to be able to find the correct translation for :
*Chronic inflammation in oral cavity /Allergic gingivitis (an autoimmune disease in the oral cavity).




However note that some of those diseases have yet not occured in Swedish Basenjis, and that in general they seem to be a small problem in the breed (of course for the owner of a Basenji that does become ill, that isn't much of a comfort), but still overall, Basenjis have a high life expectancy.



By the way, about the Fanconi syndrome DNA-test that I mentioned in my other reply, they have since about 2 years or so been able to get a more definite test result, so it isn't just probably this or that test result anymore.


Also by the way, personally I prefer being told that these diseases does occur and this is what we do to try and avoid them, rather than those crossbreed breeders that believes that all their puppies must be innate healthy, when Optigen for example actually offers 2 different DNA-test for inherited diseases if you have a "Cockapoo" ( http://www.optigen.com/opt9_test.html ).
 
Thankyou for that,so glad that Basenjis do not have LAD,it is a horrible always fatal disease.
I think an awful lot of these afflictions were thee but not identified.Labradors "got stiff" after seven,shepherds too,old dogs got cataract,it wa just accepted.Now we have vet science ,DNA etc to help us breed even better dogs than before.PRA is not an invention of "show" people,in fact gundog lines have it more,there is one male with late onset still trialling...and no doubt some will doubt the Optigen result too!
Having been involved for over a couple of decades with a breed blighted by an unpredictable blindness I can only thank the Lord we can now be free of it.
I am still of the opinion that feeding has an awful lot to answer for,especially in skin and behavioural issues,and as a result only feed raw natural food.It is just a base fact that the ingredients are waste combined with cereal ,that no wolf would ever eat,that to me makes even the most expensive just a very expensively bought waste disposal system.
 
Alec Swan said:
My "Quote" button wont work, so posted byI remember the first Lancashire Heeler that I saw, back in the early '80s, and what a super little thing it was. Then I saw more, as they became more popular, and every single one of them, was a delight. I may well be wrong, but at the time, they either weren't, or had only just been recognised by the KC. What has gone so wrong for them, where we now have a breed which has grown to achieve problems which simply didn't exist previously? We knew enough about heritable problems in certain breeds THEN, so how have we created the problem? Is it simply a case of a breed becoming popular and a case of over breeding?

It's all very sad, and I suspect that there are those who fiddled whilst Rome burnt.

Alec.
Click to expand...

Alec I bought my first 2 Heelers back in the 80s and its was known about PLL then but there was no way of testing so breeders tended to breed away from lines with known problems. Now we have the DNA test and we know for sure but back in the day I believe the breeders did a good job. My LHeeler is no different from my first 2 and has all the breed traits and characteristics I remember so well.:)
 
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