28/01/2015
How to determine your dog's (or hypothetical breeding) XY factor
Start out by numbering a copy of your 4-generation pedigree.
The Sire is 1.
The Dam is 2.
The paternal Grand Sire is 3.
The paternal Grand Dam is 4.
Maternal Grand Sire is 5.
Maternal Grand Dam is 6.
Back to the top of the pedigree with the Paternal Great-Grand Sire is 7.
Now numbering straight down the Great Grandparents ending with 14.
Back to the top of the pedigree with the Great-Great-Grand parents numbering 15 through 30.
On a Bitch's Pedigree (XX)
Locate and highlight the key positions that contribute the most to her genetic makeup .
1, 2, 4, 5, 6, 9, 10, 12, 13, 14, 20, 21, 22, 25, 26, 28, 29 and 30
The strongest x factor are the bi***es in the positions 2, 6, 14 and 30, these bi***es are the “ tail female ” line, because that x chromosome is passed along with the least amount of change (mosaic). These bi***es contribute more than all of the other key positions.
If these key positions (1, 2, 4, 5, 6, 9, 10, 12, 13, 14, 20, 21, 22, 25, 26, 28, 29 and 30) are STRONG in your pedigree, you have something good to work with, now breed her wisely.
If your key positions are occupied/dominated by non-champions, poor showmanship, unhealthy, low ability, bad mothers &/or poor temperaments, you probably need spay and place this bitch. You will be spinning your wheels and wasting your money trying to breed up from something that is not plausible for bettering.
The “ black holes ” for bi***es are in positions 3,7,8,11,15,16,17,18,19,23,24 and 27. These dogs contribute little or nothing to the offspring. The dog (xy) that precedes it only passed his Y chromosome, because a bitch is (XX) it takes these dogs influence out of the equation.
On a Dog's Pedigree (XY)
Locate and highlight the key positions that contributed the most to his genetic makeup .
1, 2, 3, 5, 6, 7, 11, 12, 13, 14, 15, 24, 25, 26, 28, 29 and 30
Again the strongest X factor are the bi***es in positions 2, 6, 14 and 30, these positions are the “ tail females ” who are still key positions in a dog's pedigree. However the “ tail males ” are the males who's Y Chromosome gets passed along with the least mosaic, they are in positions 1, 3, 7 and 15. These “ tail males ” are very important to the male offspring produced in any litter. The “ tail males ” influence is most of what male offspring receive from their father's pedigree.
The “ black holes ” on a male dog's (XY) pedigree are in positions 4, 8, 9, 10, 16, 17, 18, 19, 20, 21, 22 and 27. Remember only the Y chromosome is being passed along on the sires side. These “ black hole ” dogs have little or no genetic influence.
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The XY Factor
Breed to Succeed
As I have studied and practiced dog breeding I have discovered that breeding for both genotype (genetic makeup) and phenotype (physical appearance) is a necessary consideration for the complete dog. “Complete” meaning health, temperament, function and type all consistently exhibited in a litter. Line breeding can work wonders to lock in both good genotype and phenotype, but my attempts were more hit and miss. The pedigrees looked like near perfection on paper, but I wasn't getting the consistency throughout the litters. My problem was that I did not understand that some of the dogs that I was trying incorporate were falling into “ black holes ”.
“ Black holes ” (for the lack of a better term) are positions in a pedigree that for genetic inheritance reasons, tend to have little or NO effect on the offspring. These “ black holes ” are different on a male's pedigree versus a female's pedigree, because there is more genetic material (information) on a X chromosome versus a Y chromosome. This is called the X Factor, the racehorse community conducted a study about why famous stallions (namely Secretariat) couldn't reproduce a son that was equally as talented as his father. What they found was that Secretariat's daughters got a gene that they could pass on to their sons (Secretariat's grandsons) and those grandsons in turn could pass that on to their daughters. It was a sex-linked gene, Secretariat did not pass on his “maternal” information to his sons on the Y chromosome. He was only able to pass this genetic information to his daughters on the X chromosome.
The second theory was brought up at a “dog breeding” seminar put on by one of the well-known breeder/judges in reference to the “ tail male ” or “ tail female ”. These “ tail (fe)male ” dogs being the strongest Y or X positions of inheritance in any pedigree.
These “ black holes ” & “ tail (fe)male ” are interesting theories, which so far is ringing true in my own breeding program. When I start looking at breedings that I have done in the past that worked. Then look at others that looked just as good as far as the line breeding coefficients, but turned out with a big fat flop. I used this XY factor formula (in hindsight) and the breedings that did NOT work as well were INDEED breedings where the line breeding fell into those “ black holes ”. The successful litters fell into the highlighted areas (key positions) perfectly as expected by the theory. I found this totally amazing, it predicted my successes and my failures right there on the paper. Now if I had only known about this theory in the preparation stages, I could have had more consistent litters. Anyone can “get lucky” and have a surprise success, even when the numbers don't add-up, but to be better prepared is to have better consistency & consistency equals success.
I've always been told, “beg, borrow and steal to get the best brood bitch you can possibly get your hands on”. It makes perfect sense now. It is eye opening when you start to realize that the strength of a breeding program truly is in your bi***es & not the stud dog that someone is specialing all over the country. Not that the stud dog isn't important, but the brood bi***es are the key.
It has totally changed my way of thinking when I am considering a breeding between any two dogs. A pedigree can have the best dogs ever, but if those dogs are in “ black holes ” they have very little effect on the breeding. So now, even pedigrees that have dogs in them with traits that I do NOT want … I CAN consider using the dogs if the objectionable ancestor is located in a “ black hole ” position in the pedigree. The key is to double or triple up in key positions for the most successful impact on the offspring.
