Page 37 - 12 April 2013

The Power
by Larry Thornton
Three Bars
One aspect of our look at Three Bars and Top Deck in these articles that didn’t come out was how the sire lines of these two stallions would go on to impact the breed.
of a Sire Line
The sire line then traces or eventually goes to a prominent stallion that becomes the foundation sire of that line. It is these sire lines that become a reference point in the study of the pedigrees and the mating patterns that have evolved through the years.
One of the common ways for this sire line influence to appear is through a nick. The usual definition of a nick is the phenomenon that takes place when a stallion is crossed on a mare or mares from another bloodline that produces superior foals. Thus we can say in this case that a nick occurs when a stallion from one sire line is mated with mares whose sire is from another sire line and that cross produces superior foals.
The stallion we breed to comes from a distinct sire line. The key genetic factor that defines that sire line comes from the Y part of the XY sex chromosomes that make him a male. It is the Y chromosome that is passed from a sire to his son, determining the sex of the foal as a male. The stallion passes his Y sex chromosome to his sons just as he passes his mother’s X to his daughters. This sets up a similar situation to the Mitochondrial DNA that we inherit from our mothers, giving us a unique genetic tie to the mare. The Y chromosome gives a colt a unique genetic tie to his sire.
The study of the Y chromosome through modern genetics has introduced us to some interesting facts about the influence of the
Y chromosome. They have found that the Y chromosome has less genetic information than its counterpart the X chromosome. They have also found that there is genetic information passed down generation after generation that is consistent through what they call haplotypes. Haplotypes are sets or groups of genes that pass on to the next generation together. These haplotypes, or groups of genes, carry certain markers that identify the specific information telling us where the individual comes from. These markers have allowed geneticists to trace migration patterns of people through history and are a part of paternity testing when trying
B
One aspect of our look at Three Bars and Top Deck in these articles that didn’t come out was how the sire lines of these two stallions would go on to impact the breed. The sire line is that line in the bracket pedigree that follows along the top line of the pedigree. It starts with the individual’s sire and then on to his sire and so on through that top line of the pedigree.
ack in 1985 I did a three part series for
Speedhorse on the influence of Three Bars and Top Deck on modern Quarter Horse racing. The premise of the first two articles was to show how each of these now legendary stallions came to influence the breed through the performance of their offspring. The final installment took a look at how the blood of these two stallions was going to intermingle to influence the breed and the role inbreeding or linebreeding would play in the perpetuation of their bloodlines.
SPEEDHORSE, April 12, 2013 35
million dollar sires
Speedhorse files