134th Kentucky Derby

A Vivid Demonstration of the
Benefits and the Perils of Inbreeding

What a spectacle the 134th Kentucky Derby was! The favorite, Big Brown, came from the outside and behind to win with energy to spare. Second place was Eight Belles, the only filly in the race, who passed the finish in fine form, but then with no warning her two front ankles broke in the run out.

Trainer Dutrow was heavily criticized for his effusiveness on the subject of Big Brown prior to the race. After the Derby most of the critics were stating that now they knew what he meant and "it is not bragging if you win". Big Brown is certainly special. The ease with which he pulled past the leaders and flew to the post was wonderful to watch. What a horse! We haven't seen one like him in a long time.

Almost as astounding was the performance by the courageous filly, who obviously had the immense talent needed to be a Derby contender. In a spooky reminder of Ruffian, Eight Belles, a large, dark, leggy filly, with the extraordinary ability to leave 18 of the best colts of the year in the dust, demonstrated a fatal brittleness as well.

Eight Belles and Big Brown Flying
to the Finish (AP/Morry Gash)

The pedigrees of these two stars do not disappoint us- the story is there to see. First, the spectacular Big Brown is an inbred horse. The pedigree scholar Floyd Brown gives us a fascinating analysis of Brownie showing an intriquing connection to the great Domino's lineage structure. Link to the Blood Horse article by Floyd Brown We can see this same basic pedigree pattern in the sport horse Noteworthy, a great performer and sire.

Big Brown- pedigree

Inbred horses are seldom top performers, but when they are, they are amazing. I felt a factor in Big Brown's performance success is that his inbreeding is of a complex type. His sire and dam are clearly related being both by Northern Dancer sons- generally a no-no in linebreeding. However, the main concentrated power is coming instead from their dams. Edge, the sire's dam, and Syrian Circle, the dam's 2nd dam, (2x3) are 3/4 genetic sisters. Remember from our American Thoroughbred page that 3/4 siblings close up delivers speed. This identifies for us that the most power is traveling up the dam lines. Further, the dam Mien is 3x4 to the full siblings Thong and her brother Lt. Stevens. Full siblings give the needed class and quality to run the classic distance races.

The female power is further reinforced by the full siblings' (Thong/Lt. Stevens) 4th dam: Goody Two Shoes, is found also on the tail female line, and the 4 Nasrullah lines in Brownie also trace to Goody Two Shoes. This is what the Thoroughbred experts have said will give lasing racing and breeding success, to build up a strong maternal line - see the Mare.

Goody Two Shoes is considered a "reine de course" or "Blue Hen" by the Thoroughbred industry, a mare that is genetically pre-potent for racing success and with many top descendants.

Starting in the 6th generation the genetic activity picks up strength again, with multiple duplications including the full sibling power in Sickle/Pharamond, Bull Dog/Sir Gallahad, and the 7/8 siblings Riot/Fairway. This type of construction in the back of the pedigree guaranteed that Big Brown could also go the distance (see Stamina and the Thoroughbred).

We mentioned above that Big Brown carries a close up duplication of sons of a sire, something that as linebreeders we try to avoid because it tends to deaden the ability coming through to the foal. The only time the experts say that this can work is when there is an equally strong presence of daughters of another sire, and this they say can work as a sex balancing of sorts, plus add some hybrid vigor. We haven't discussed this particular pedigree structure earilier because, it is an exception to the "rule", and is used by only the most knowledgeable of breeders.

Here the breeder has created a hybrid vigor, as the second and third dams being 3/4 sisters by Damascus out of Round Table daughters, creating an outcross factor with the Northern Dancer sons.

We would expect a sprinting talent from the 3/4 sister placement 2x3, and classic distance from the full siblings 4x5, and the far reaches activity gives stamina, a pedigree construction that appears to have resulted in a level of talent similar to St. Simon and Nearco- able to go all distances, accelerating from any position. You are probably thinking- yeah, what about similar to Secretariat? We will see after the Preakness and Belmont, but barring a tragedy like Big Brown being sterile, the difference between Big Brown and Big Red will be that Brownie should be a better sire than Secretariat (he is tighter bred up close).

Eight Belles, inbred 3x4 to the premier sprint line: Mr. Prospector, would appear at first to be just a sprinter also, but then we see her background concentration gives her stamina as well. In addition, she carries reinforcement to this front power with another line of Mr. Prospector's sire, Raise A Native, making him 5x4x5 (all sons). Raise A Native, one of the top sire lines in this country because of the huge racing talent he gives, can also passes on fragile front legs, particularly the ankles. But while knowing about this possible weakness most race breeders decide that it is worth taking the chance of a breakdown to get his winning brilliance into their foals. It is a balancing act, if they can add enough strong soundness, and still keep the Raise A Native powerful, then they might have a super star.

Eight Belles lineage is loaded with top of the line racing stars- giving her ability in distance also, but like Ruffian, the fragile line is the most reinforced and it must have overriden the sound influences she carries.
Eight Belles- pedigree

Our hearts go out to the owners, breeder, trainer and handlers of Eight Belles for their loss of so beautiful, so courageous, so grand a girl.

Breeding is a risky business, no matter what your goal-sport or racing, concentrating the genes that bring down talent to the foals, also carries the chance that some negative recessive gene will surface. If you breed long enough you will find that you will be culling stock with great sport ability, because they carry some other negative trait that you don't want in your herd.

How well I know that sickening feeling that settles in the day you realize that the bloodline you have built up so carefully has a major fault in it. Then comes the struggle to either correct the defect in the next generation without losing the talent, or the decision to cull because it will take too long or too many generations to fix it.

Recessive genes are hidden, that is the problem, you don't know your horse carries one until it is reinforced and therefore displays itself. Every breeder faces this issue. When do the benefits of the bloodline out-weigh the unwanted trait. Do you throw the genetic baby out with the bath water, or soldier on? It is a tough decision we are all faced with- it is part of the business. We try to lessen our risks by researching the bloodlines and carefully planning our matings, to achieve the best sport outcome with the least drawbacks, but there will always be risks.

The Quarter Horse industry faced this quandary with the offspring of the stallion Impressive. Like his name he was the pinnacle of the muscular Quarter Horse conformation. He was used extensively because of his pre-potency for his fabulous physical type (over 2000 foals). Unfortunately, as time went on it became apparent that he was also pre-potent for a dibilating muscular disease, now called HYPP, previously unknown but now tested for in breeding Quarter Horses.

"Although he never exhibited symptoms of the disease himself it gradually became evident that many of his descendants were inflicted with a painful, alarming and often fatal disease. The disorder has never been observed in horses of other lineage." (Dr. Glynis Scott)

Breeding horses is an expensive gamble, but when it works the joy it gives us makes the struggle worth while.

Back to Pedigree Generation Position

Back to the Mare
Back to American Thoroughbred