Breeding coefficients

[Fran Griffin]

Just out of interest, I have just been looking at the inbreeding coefficients of some of the litters currently available and have discovered that many of them are way over the breed average of 13.4  one litters coefficient is way over 25.

I am wondering if breeders are bothered that they are producing litters with these results? If not can somebody please explain to me, as a Setter pet owner why this is so?  If I was currently looking for a puppy, these kind of results would make me look elsewhere.

[eva ciechonska]

Susan, you have missed out two influential UK sires:
ShCh Thendara Kennedy who sired 449 offspring from 52 litters
ShCh Thendara Don Corleone who sired 180 offspring from 25 litters. Again there could be a discrepency between actual data and Mate Select data because of the ATC numbers.

[Susan Stone]

Thank you, Eva. That was not intentional, I just looked up a select few on Mate select that came to mind and not doubt numbers will not be 100% as I am sure some pups are never registered.

 

[Susan Stone]

Hi Mel,

I meant my post as a general thread discussing breeding traditions, not aimed at accusing you of being personally responsible for the Popular Sire Syndrome;-)

[Margaret Sierakowski]

Thanks for the link to Jeffrey Bragg's article , its about the most succinct and comprehensive summary of how to breed using knowledge of population genetics. And a wake up call about breeding in a way that is good for the whole breed rather than to produce one or a few exceptional dogs

[Margaret Sierakowski]

With respect, Greg, your ideas are  out of date. Twenty or thirty years ago, it might have been thought that identifying DNA markers would solve most canine health problems, and some basic understanding of Mendelian genetics was as much as most breeders needed. Genetics has made huge advances, and today population genetics should play as big a part in dog breeding as the use of DNA testing. And yes, there is now plenty of scientific evidence that loss of genetic diversity IS causing health problems in pedigree dogs, DNA testing for a few genetic diseases is not enough - and as gene pools shrink, the chance of doubling up on recessive genes increases, one cannot continue indefinitely doing more and more DNA testing (and discarding more dogs from the breeding stock) to keep a breed healthy.

[david lyus]

I think the answer to this humans have have an open gene pool there are millions of us and popular sires of irish setter stud proportions went out with genghis khan ;if for example  you have a child with cystic fibrosis its possible  to test to see if siblings are affected( two copies of the gene) or carriers of one copy of the gene. carriers partners can be tested to see if they are carriers; if the partner is not a carrier a proportion of children could be carriers but not have the condition;The unborn child  of a double carrier union can be tested to see if a carrier or affected .I did read somewhere if there is a bottleneck in the human genome its the diminishing variety of the male sex y chromosome

[Margaret Sierakowski]

Not caused in the sense that loss of genetic diversity creates a  mutation, but the speed with which  a mutation spreads through the breed is very much affected by inbreeding and use of popular sires. Why do you think the gene for rcd4  became so widespread in both Irish and Gordon Setters? Thats why understanding of population genetics matters as much as understanding Mendelian genetics and the use of DNA testing. And loss of diversity is also linked to problems such as weakened autoimmune systems, loss of fertility, smaller litter size, smaller puppies , poor dentition

I understand that its hard to change the way many older breeders think , and not a lot of point in arguing endlessly with people who grew up believing that selection of the "best" and close breeding was the way to produce winning dogs with the desired  "type". Also breeders who have spent twenty or thirty years developing a line with recognisable type are reluctant to breed away from that line ,even if staying with it means producing dogs with health problems. Doing a couple of DNA tests doesnt make a healthy dog, it only reassures the breeder and puppy buyers that the dog is clear of a couple of specific problems

It is hard to change the way one goes about dog breeding, and I can understand why - ten years ago I was very against outcrossing and argued that we had a sufficient gene pool in IRWS which if used would continue to ensure healthy dogs, and it took a lot of listening and reading to open my mind . The start was joining Dr John Armstrong's Canine Genetics group. Meanwhile I could watch the COIs starting to rise in my own breeding because I couldnt find healthy alternative stud dogs to use. Younger and newer breeders seem to find it easier to keep up  with advances in genetics , and to grasp a different paradigm for breeding healthier dogs. And very importantly , the Kennel Club is moving in this direction too.

[Rhonda Fisher]

It is wonderful Fran and Margaret that the Kennel Club is forward thinking and also makes the information available to the public. Allowing setter owners to use the tool to acquire a lower COI pup when a breeder takes this into account and steer clear of those that don't. Combined with the results of other tests for Clad , Pra etc it all helps non breeders immensely as well breeders if they choose. Hopefully our own Kennel club will be working toward such a public way of promoting healthy pedigree dogs.

[Susan Stone]

Greg, you say:

The link between the breeding co efficent and health has never been established and lacks scientific credibility.

No? I suggest you start with the Habsburgs and carry on from there. I look forward to reading your peer reviewed proof that inbreeding has a positive effect on Canine Health.

To suggest that English Setters and Gordons should need to look outside the breed when there are a wealth of bloodlines internationally is simply absurd.

Has this been suggested?

[Margaret Sierakowski]

Well, the Kennel Club are saying that English Setters are one of the five endangered breeds for whom a breeding strategy , which could include importing new dogs,outcrossing and limiting the use of popular sires,  should be considered. But I'm not aware of any actuall proposals of outcrossing.

IRWS are the only setter breed where outcrossing has already  been used to widen the gene pool , but we are fortunate in having both working IRWS who are not too different from  the show bred IRWS, and working red Irish Setters who are very similar to the working red and whites except in colour, so its not "absurd" to consider outcrossing

[david lyus]

our red has a coi of 23% where the breed average is about 16 she has about 120 half siblings  and the vet loves her unlike our ex insurance company whom we decided to let go

[Fran Griffin]

Well one of my reds has a COI of around 11, and the vet loves her, and the insurance company hates her, but there is something genetic going on, as I am in contact with the owner of one of her siblings, and I know there are similar problems going on there too. Before her breeder died, I did managed to discover that another relative appeared to have the same problem, and it could be that Tally's dam did too :-/