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Kim N
8th January 2012, 12:49 PM
In my search for the right puppy I am looking for parents who have been MRI tested. I am running in to a lot of only the sire tested. Why is this and is it normal?

sins
8th January 2012, 01:09 PM
Hi Kim,
It's not unusual.
But there are litters who have both parents scanned.There's much greater availability of puppies from scanned parents now than even a year ago.
Having both parents scanned SM free cannot guarantee that your puppy will not go on to develop SM over it's lifetime,but breeders who have been scanning for a while seem to have done well in eliminating early onset SM in their lines.If you wish I can PM you with some names of breeders who have litters on the ground or who will have them in early 2012.
I'd also recommend contacting Sylvia lymer, who operates the cavalier Club puppy register and has always been very helpful to puppy buyers.
Sins

Kim N
8th January 2012, 01:32 PM
Thank you Sins, Any help would be greatly appreciated. I do know that and my husband and I discussed it yesterday what the chances are that we will do all the right things in finding a puppy and might well end up with SM in the future anyway. Sometimes I wish I hadn't fallen in love with this breed as I see the pain that you and others have endured but we can't help who we fall in love with can we. I can't do much to help this breed but I think if nothing else it is my small contribution to this beautiful breed to only buy from breeders who are doing right by them and doing all the right testing. I have already seen that breeders who are not testing do not like when the questions are asked, hopefully more people will ask before buying and these breeders will eventually be forced to do what is right when they see potential buyers walking the other way.

sins
8th January 2012, 01:35 PM
Also,talk to margaret C on this forum who can also help with advice re: breeders.
I always feel it's better to hand over your hard earned money to breeders who have the best interest of the breed at heart and the interest of the pet buyer rather than their own profit.
Sins

Margaret C
8th January 2012, 02:17 PM
In my search for the right puppy I am looking for parents who have been MRI tested. I am running in to a lot of only the sire tested. Why is this and is it normal?


A lot of breeders still try and minimise the risk of SM and make themselves look like half-way decent breeders by using one scanned parent.
A little word of warning here. With breeders that 'fudge' the guidelines like this you will sometimes find the 'Scanned Sire' has often been MRI'd much too young for the result to be worth much.

The truth is these breeders are saving themselves money by not paying for the testing of the other parent.

Another strong motive for not scanning one parent is that breeders will want to use a cavalier they consider 'desirable' in their breeding programme. If they have it scanned and it has SM they may be faced with a decision they don't want to make. If they don't scan they can convince themselves that all is well, mate it to a scanned partner, and still feel fairly good about themselves as a breeder.

Studies show that litters from these breedings will produce over 50% of early-onset SM. In other words, these breeders are still making the situation in the breed worse.

You may have a long search to find a breeder who has a litter of puppies that have both parents MRI scanned after they are 2.5 years (as per the guidelines now, although they will soon change slightly ) but they are out there and they are worth hanging on for.

Studies have shown that you have a much better chance of obtaining a healthier puppy if the parents are both grade 'A'

I have a website that shows copies of the three health certificates you should be shown by any responsible breeder.......... www.cavalierpuppy.co.uk (http://www.cavalierpuppy.co.uk) .
I also have more detailed advice and a list of breeders that may be able to help you.
PM me with your email address & I will send it to you.

ByFloSin
8th January 2012, 02:29 PM
I take on board what Sins and Margaret have had to say. However, unless I am so tired that I have missed mention of it, I think it is virtually worthless to breed a litter when only the sire is favourably scanned because I believe it is an accepted fact that the bitch (dam) contributes 80% of the genetic inheritance to the pups, whereas the sire (dog) only gives the remaining 20%.

On that basis, were I purchasing a puppy, and only one parent could be scanned, it would have to be the mother before I would show any interest in the litter.

Margaret C
8th January 2012, 03:31 PM
I take on board what Sins and Margaret have had to say. However, unless I am so tired that I have missed mention of it, I think it is virtually worthless to breed a litter when only the sire is favourably scanned because I believe it is an accepted fact that the bitch (dam) contributes 80% of the genetic inheritance to the pups, whereas the sire (dog) only gives the remaining 20%.

On that basis, were I purchasing a puppy, and only one parent could be scanned, it would have to be the mother before I would show any interest in the litter.

Hello Flo,

Welcome back, I'm really pleased you are feeling strong enough to join in the discussion.

I was not aware that the figures you give about the parent's contribution to the puppy's genetic inheritance were established fact? I would certainly be very interested to know where I can read more about this study.

I have to say that, despite who gives what percentage of inherited genes, after reading the report 'Effectiveness of breeding guidelines for reducing the prevalence of syringomyelia' ............... http://www.cavalierhealth.org/syringomyelia.htm#Effectiveness_of_breeding_guidel ines
there is no way I would settle for anything but both parents scanned when properly mature.

Kim N
8th January 2012, 06:09 PM
Thanks everyone.

I agree with you whole heatedly Sins. I think it may cost more but totally worth it in the long run, not only for my pup but for the breed as whole.

Margaret, I am still learning but that was my immediate thought as well. What is the point in having only one scanned other than to be able to say you have testing? It means nothing to me, as novice as I am unless you have scanned them both. I also see many saying they have all the appropriate tests and then it is only heart and BVA eye tested with no mention of any other testing. It's breaking my heart really to see how fast these litters seem to be selling despite the lack of testing. I have already been to your site and printed out the sample copies of the tests, thanks for that.

Karlin
8th January 2012, 06:15 PM
Glad to see you back, Flo! :)

I am with Margaret on this one -- I'd be very interested to know of studies that show dams are more important genetically. Are the people claiming this more informed than, say, leading global canine geneticists (whom they also quote when it suits them, of course) like Jerold Bell, who has written quite a bit on "popular sire syndrome' and has expressed concern at what is happening to pedigree dogs due to massive overuse of just a few sires? Nowhere here, for example, does he express concern or indicate about dams having any extra influence compared to a popular male (and of course no one talks about 'popular dam syndrome' :) ):


Popular Sire Syndrome and Concerns of Genetic Diversity

Jerold S. Bell, DVM
Department of Clinical Sciences, Tufts Cummings School of Veterinary Medicine
North Grafton, MA, USA
There is a tendency for breeders to breed to the male who is the top-winning dog. This can also occur with a popular dog that has OFA excellent hip conformation, or has produced no epileptic offspring in matings to epileptic dams. Regardless of the popularity of the breed, if a large portion are breeding to a single stud dog, (the popular-sire syndrome), the gene pool will drift in that dog's direction and there will be a loss of genetic diversity. Too much breeding to one dog will give the gene pool an extraordinary dose of his genes, and this will include whatever detrimental recessives he may carry, to be uncovered in later generations. This can cause future breed-related genetic disease through what is known as the founder's effect.
Along with the thrill of owning a popular sire, comes your responsibility to the breed. Over time, you will find out what detrimental genes he carries. Hopefully these will cause minor faults, but occasionally they may cause genetic disorders. The true measure of a conscientious breeder is how this knowledge is disseminated to the owners of the next generation.
Purebred dog breeds have closed studbooks. No new genes are available to the breed, except from infrequent mutations that are usually not desirable. Considering a breed as a whole, genes cannot be gained through selective breeding; they can only be lost. This has lead breeders to question whether a pure breed can go though hundreds of years of selective breeding and still maintain its health and viability.
All genes come in pairs: one from the sire and one from the dam. If both genes are of the same type, the gene pair is homozygous. If the two are different, the gene pair is heterozygous. While each dog can have a maximum of two different genes in a pair, many different genes are potentially available to be part of the pair. The greater the number of genes that are available to each pair, the greater the breed diversity. ...
The loss of genes from a breed's gene pool occurs through selection: the use and non-use of offspring. If a popular sire is used extensively, gene frequencies, and the gene pool can shift towards his genes, limiting the breed's genetic diversity.


Or this well known article by CA Sharp, who writes widely on genetics issues in dog breeding? http://www.canine-genetics.com/Popular_sires.htm and of course this one which is so appropriate to the cavalier clubs and kennel clubs right now: http://www.dogstuff.info/sleeping_dragons.html from which:


Breed Clubs tout themselves as guardians of all that is precious in their breeds. Most, if not all, have codes of ethics. But codes of ethics tend to be toothless documents that get dusted off and waved about only when a club is accused of not having addressed an ethical issue.

Codes of ethics ought to have sharp teeth, but this is not enough. Breed clubs should spend a lot more time-and money-educating their members and the public about the hereditary problems in their breeds. And on funding research on those problems.

No single entity will be more aware of what a breed's genetic drawbacks are than a breed club. It is in an excellent position to monitor those which have already been identified and look out for new ones. Someone needs to bring the attention of the veterinary community to specific breed concerns. Who better to do so than the organizations that allegedly exist for the protection and improvement of those breeds?

...

Urging people to lie, intimidating them into silence, even threatening them, is not ethical behavior. Not for breeders any more than anyone else. Nor is it ethical to heap scorn and ridicule upon those who exhibit the moral courage to be open about hereditary disease.


Even if a dam did give 80% of genetic inheritance, they have a limited number of litters and do not remain anything like as major an influence as a popular sire used hundreds of times, siring hundreds or event thousands of puppies, many of them that may be retained, shown and then bred to yet other dogs closely related to that sire.

This is currently happening with a few popular sires in cavaliers in the UK, as anyone involved in showing knows very well. There are not even 6 degrees of separation between some of the dogs being bred, as a result.

Along with increasingly well informed puppy buyers who will not buy puppies from unscanned parents, it is breeders themselves who want scan information on sires, and the fact is that few are getting scanned. Responsible breeders already scan their dams.

Kim N
8th January 2012, 06:26 PM
I am also seeing lots of adds saying the dams are scanned but no mention of the sire just saying to me that they aren't as careful about the sire they are breeding with.

I had no idea really how much work was going to be involved in finding a truly responsible breeder.

anniemac
8th January 2012, 07:38 PM
I would not say having only one parent scanned means the breeder is not responsible but I would personally want both parents scanned even know the status of the grandparents.

The reason I say that is because they technically could be following the SM protocol at the time. I know in the USA of well meaning breeders that have used a sire scanned over 5 A to an unscanned bitch (I hate that word). The problem with this is what Karlin mentioned of it could lead to popular sire syndrome.

I just want to say just because only one parent is scanned does not mean the breeder is not responsible. Sins said she knew of some breeders with both scanned so I would get with her if that's what you are looking for.

I don't know about genetics but I have heard both sides. A scanned older stud clear could be valuable to those unscanned because the could (how do I say it) produce more. However as Karlin said the problem could lead to popular sire.

I have read that some breeders would want the bitch status known because if they did have SM and were not symptomatic they do not know what the pregnancy would do. (would it be hard on them or then be symptomatic).

Either way, I would want the status known on both because of recent studies and having a cavalier with SM. I don't know why only one scanned in UK but I do know that researching and finding a puppy is so important. I would want to get to know the breeder and I'm sure they would too. It's such a big addition.

Good luck on your search :)

ByFloSin
8th January 2012, 07:54 PM
I have no idea what the study giving the 80/20 percent figures is. I got the information a couple of years ago from a friend who went on various KC or KC approved courses for judges. I will try to get more information if she has it.

anniemac
8th January 2012, 07:56 PM
Let me add that far more are not scanning at all in the USA and I don't feel that because of this that only one scanned is enough. However, I hope more and more do scan so we know more history.

Kim N
8th January 2012, 08:00 PM
Hi Anne, Thanks so much for your input. I appreciate what your saying. Not having a lot of experience with the breed and reading all I can get my hands on with tons and tons more to learn, all I know at this point is that I want to give my pup the best chance at a happy, healthy and pain free life. So to me that means having both parents (and yes, grandparents too if I can) scanned.

I can see that things are changing rapidly and that protocol seems to be changing so maybe not all breeders are doing the same.

You guys are great and I am learning a great deal from you, thank you again!

Kim N
8th January 2012, 08:03 PM
Let me add that far more are not scanning at all in the USA and I don't feel that because of this that only one scanned is enough. However, I hope more and more do scan so we know more history.


That's good to know since eventually we will be back in the US. It would be nice to get more on board for scanning both.

RodRussell
8th January 2012, 08:32 PM
I am also seeing lots of adds saying the dams are scanned but no mention of the sire just saying to me that they aren't as careful about the sire they are breeding with. ...

If you are looking randomly at breeder websites, they probably are mentioning only bitches being scanned because they don't have males. However, if they are referring specifically to the sire and dam of a litter on the ground, then I think it is a plus that the dams have been scanned. See, e.g., this article from June 2011: http://www.cavalierhealth.org/editorial.htm#June_13,_2011:

It probably should go without saying, but keep in mind that "just" scanning a cavalier is meaningless. Important points are the age of the dog when scanned, and, of course, the results of the scan.

Kim N
8th January 2012, 08:38 PM
Thanks Rod, I am keeping those points in mind. So far of the few I have sent questions to I am not getting full answers. ie when asked the age of parents I am getting some answers to other questions but no answer to that so just moving on. In the end I won't just be taking the fact that they are scanned but will be wanting to see the certificates.

Off to read the article you just posted...

RodRussell
8th January 2012, 08:43 PM
... So far of the few I have sent questions to I am not getting full answers. ie when asked the age of parents I am getting some answers to other questions but no answer to that so just moving on. In the end I won't just be taking the fact that they are scanned but will be wanting to see the certificates. ...

That reminds me of cavalier breeders who will advertise that their breeding stock has been OFA-certified to be clear of mitral valve disease (MVD), but when you look at the actual certificates you will find that the examining veterinarian was not a cardiologist, or that the dog was certified when it was, say, 18 months old, etc. Such OFA certifications are worthless.

Margaret C
8th January 2012, 08:57 PM
Thanks Rod, I am keeping those points in mind. So far of the few I have sent questions to I am not getting full answers. ie when asked the age of parents I am getting some answers to other questions but no answer to that so just moving on. In the end I won't just be taking the fact that they are scanned but will be wanting to see the certificates.

Off to read the article you just posted...

Thank you for what you are doing. Puppy buyers like you are so important to the future of the breed.

We need buyers ask questions about health testing and walk away when the breeder does not have certificates that show they have followed the health protocols.
So many breeders are uncaring about the health of the dogs they breed, but they may think again when they fail to sell their puppies.

Soushiruiuma
8th January 2012, 09:07 PM
I have no idea what the study giving the 80/20 percent figures is. I got the information a couple of years ago from a friend who went on various KC or KC approved courses for judges. I will try to get more information if she has it.

I think this figure may be some loose use of statistics, but based on reality. Each parent contributes 50% of the DNA. But there's more to genetics than DNA, environment can play a huge factor, and the early environment is entirely on the dam side, everything from the number of puppies, to the chemical composition of milk, and the quantity of milk produce (and several other factors). The sire contributes nothing to the environment.

But not all traits are environment linked (coat color, for example, will not be affected by environment interactions). And to say that environment contributes 35% of the offspring traits, would be totally bogus. It's not a fixed amount, and different traits are influenced differently by environment.

That's the only thing I can think that would let them swing the outcome so heavily towards the dam.

Brian M
8th January 2012, 09:27 PM
Hi Kim

You are a star for doing this so best wishes in your search .When my Lily came to me 2 1/2 yrs ago she came from two scanned A parents
but it took me a time to find her, but I also wanted a female Black and Tan and finally with Margarets help the little horror:) was found in the end up near Glasgow .