Taking Charge of the Pedigree

re: Taking Charge of the Pedigree

Greythorobred — Thu, 12 Apr 2012 02:09:29 GMT

I have a mare by Rubiano out of a Dynaformer mare--I noticed that she crosses well with son's of Giant's Causeway, would son's by AP Indy also be a good cross on her--just trying to get some idea as to which way to go--this would be her 1st foal--thank you---

re: Taking Charge of the Pedigree

Ian Tapp — Mon, 09 Apr 2012 20:05:15 GMT

Hi Robert,

In reply to your "large heart" comment, I thought I'd share something Byron Rogers said in the comments for an earlier Princequillo blog:

At the Pedigree & Genetics symposium earlier this year, four world respected equine geneticists - Dr Jamie Macleod, Dr Emmeline Hill, Dr Steve Tammariello and Dr Matthew Binns, all confirmed that the myth of the x-factor was exactly that....a myth. Three of the four geneticits mentioned above were part of the Equine Genome project that sequenced the horse's genome and Dr Binns co-wrote the original horse genome map.

While there may well be genes associated with large hearts, more specifically left ventricular size and wall mass, and indeed there will be genes that regulate heart stroke, there is no evidence whatsoever in their studies that the inheritance of such genes follows the mystical pattern as described in Marianna Haun's books.

It is romantic to think that the great mare Pocahontas has in some way weaved her magic through the maze of inheritance and recombination of genes, but it just doesn't work that way. Scientists who study heart size are now finding that the sire has just as much of a role in determining heart size of the resultant foal as the mare. As an example, in talking to quite a few of the companies that measure hearts they have mentioned independently that the stallion Tapit is almost homozygous for heart morphology with his colts and fillies getting a similar heart shape to his own. There is no fabled "x-factor" at work.

"While I have to applaud her for her belief in something, what Marianna Haun wrote in her books doesn't work how she has described it and it has lead many breeders astray. Heart size and function looks to be polygenic and certainly outside the scope of something that relies totally on the x-chromosome.

Genetics is going to bring a lot of things to the table in the next few years and have a lot of misconceptions and myths like this put to bed.

Byron Rogers

re: Taking Charge of the Pedigree

Robert — Mon, 09 Apr 2012 17:11:24 GMT

I always wondered if Dehere or even his full brother Defrere would blend well with A.P. Indy. In my opinion, Inbreeding to Secretariat can help if you are looking to concentrait the genes for the Large Heart and gives you a doubling up of the perfect conformational horse. I personally don't see anything wrong with that. Several years ago, there was a filly named Bishops Idea. She was 2x2 to Secretariat. Her breeder intentionally inbred her to see if the size and scope of Secretariat came through. It did to some extent, but she never ran against top flight competition. A.P. Indy with Dehere/Defrere is a cross I would not shy away from regardless of the stats. Even reversing it....Dehere on top of the pedigree and an A.P.Indy mare on bottom or a granddaughter of A.P.Indy...breeders should continue to try both ways.

re: Taking Charge of the Pedigree

sceptre — Mon, 09 Apr 2012 15:10:29 GMT

Hi Byron,

After thinking more about it, I'm sorry I made that last post. It's far too easy to poke holes in legitamate stats and requires too much effort from the other to then defend. I plead guilty to the above, and don't feel this matter is worthy of your attention.

re: Taking Charge of the Pedigree

sceptre — Sat, 07 Apr 2012 20:12:01 GMT

Thanks for that useful information, Byron. While true stats can often serve to clarify misperceptions-and numbers don't lie-, limited stats sometimes don't portray accurately the "broader" reality. I had contended that linebreeding/inbreeding Dehere mares back to Secretariat was a rather potent "nick". The stats you offer appear to contradict this conclusion. I grant that I could be mistaken-my belief derived solely from cursory observation, and not from review of numbers/stats-, but while your numbers do give me pause, I'm still inclined to trust my style of observation. While % SWs is a reasonable methodology to employ for this case, it wasn't (and isn't) the sole criteria/stimulus for how I arrive at such opinions. I admit that the SW stat often corresponds to the overall "quality runner" percentages, but I sense this isn't here (Dehere broodmares crossed with Secretariat) the case...I don't wish to split hairs, but 5.5% SW/foals is a nearly 50% improvement on average for the breed. Also, as Dehere is a relatively "young" broodmare sire, all else equal these Dehere/Secretariat offspring are earlier in their careers than average. You noted that there were 10% SWs/foals for Dehere mares with A P Indy anywhere in their pedigrees. Of those 64 foals, how many were sired by A P Indy and of those, how many were SWs? Also, I doubt that there is anything close to a 10% SW strike rate among (all) foals of racing age containing A P Indy anywhere in their pedigrees. Perhaps another revealing stat would be the % of SW for all racing age foals of Dehere mares that (the foals) were not sired by stallions containing Secretariat. There's more to play with all these statistics, but I should tell you that my focus was originally stimulated by the fact that I neither considered Secretariat nor Dehere as particularly positive influences. That's partly why I made the remark-"Dehere's brand of Secretariat"-that he may possess, and often pass on a highly desirable "cluster" of Secretariat alleles. But, such a remark as this is begging the question. I agree, first things first, there must be PROPER evidence to substantiate the observation.

re: Taking Charge of the Pedigree

Byron Rogers — Fri, 06 Apr 2012 16:12:04 GMT

Sceptre,

With Dehere as the Broodmare sire, Secretariat appears anywhere in the sire in 259 foals of racing age, 168 runners, 125 winners and 14 stakes winners (5.5% SW to foals). Take Charge Indy is the first G1 winner with the previous best being Friesan Fire and Oratory, both G2 winners.

With Dehere as a Broodmare sire, A.P. Indy appears anywhere in the sire in 64 foals, 34 runners, 27 winners and 6 stakes winners (10% SW to foals). All of the A.P. Indy/Dehere combinations are in the Secretariat/Dehere combinations so when you back these out you are looking at the Secretariat/Dehere combination without A.P. Indy at 4% SW to foals.

I would say that there is more value in using A.P. Indy anywhere in the pedigree than using Secretariat as a standalone influence. These are the type of nuances that we believe that our planned whole pedigree assessment will tease out.

Byron

re: Taking Charge of the Pedigree

sceptre — Thu, 05 Apr 2012 23:35:03 GMT

Dehere mares seem to really relish stallions with Secretariat in their pedigrees-resulting in the offspring being linebred/inbred to Secretariat. I've noticed it for a couple of years now, and from my vantage it's quite a potent "nick". The glaring "exception" to the "rule" is the excellent producer, Candytuft, as none of her first ten foals carries a Secretariat in their sire...There must be something rather special about Dehere's "brand" of Secretariat. Those who control Friesan Fire might be well advised to consider offering him more Secretariat (if far enough "back") or, perhaps, Somethingroyal alone, as there's also some evidence to suggest that the latter (sans Seretariat) works well with Dehere.