Friday, October 7, 2011

Science, DNA, and Breeding

Why do we do what we do?
I think there are many breeders that ask themselves the question why are we doing this? When a shipment is delayed when blizzards cause canceled flights, an occurrence that happened in Texas this spring. Our mares and customer's mares refusing to cycle for the early baby. The baby is born and everything is put in perspective. At that moment, there is a hush in the stall, that you feel you are intruding.
The friends you meet when the foals are placed, the excitement to watch them show, the thrill of competing and accelerated when watching a foal from your stallion winning the trophy, a World or National Title or a Futurity, but the best feeling comes when we get a letter from a happy horse owner that has found their forever horse.
I lose track of time watching the mares graze and the foals play. I enjoy watching the stallions showing their macho side trying to attract the mares to their harem, as the mares continue to graze in teh pasture with no interest in the boys. The foals develop their own traits as the grow playing with the others and disciplined by their mothers when they get a bit out of hand or don't listen.

Our horses are breeding animals, but they are so much more.
Our mares and studs are a part of a program it has taken years to develop through selective choices of proven bloodlines. We choose mares to complement our stallions and if one or two mares are retained from our stallions, we choose outside stallions to complement our mares, considering conformation and production records. As DNA is further studied, Science will be a part of the equation, as well.

Breeding is so much more than Science and DNA.
A breeding program is choosing mares and stallions that work together and have the ability to produce a once in a lifetime foal that will give you the thrill of competition and the incomparable feeling of success. Science finds the newest genetic marker. Folks on the sideline start discussing which horses should be bred and which ones not. Many feel if you can see the faults, i.e.; crooked legs, poor heads, short necks, long backs, bad hocks, and nasty dispositions maybe okay to breed forward, yet they are not traits that can be corrected or managed with a healthy feeding program and lifestyle. What you see is what you get. Some mare and stallion owners may actually give those visible qualities a pass to breed forward without thought of consequences.

The recent genetic discovery identifies the gene that has been around for thousands of years.
The latest genetic marker presented to the equine industry is the PSSM marker. It is related to the syndrome that has been in the equine industry since before registration associations were formed. This test identifies the gene that may cause a case of "tying up". The old timers referred to tying up as "Monday Morning" sickness. When horses were worked hard all week and given a day off. The following Monday morning, the farmers would find their resource of power would be stiff and unable to return to the workforce for the day or maybe longer. I'm not sure how much time was allotted to these workhorses when it was time to plant or plow.

PSSM is a condition that may go undetected for the life of the horse, until you overdo or cause stress to your equine partner. Most often it is manmade; either through over work, over supplements, or just the wrong feed. Whenever, something new is discovered, there is a learning curve and we have to adjust our programs to make educated decisions.

We have just completed testing our entire herd and are waiting for the results. We tested our studs in the spring of 2011; NOT because there were problems or symptoms of tying up; because a mare owner had tested his mares and found his mares were carriers of the PSSM marker. Believing one marker is manageable, but rather not take the 25% chance for two PSSM genes, which could be tougher to manage, we tested our stallions and found both carry the PSSM marker. A decision was made to have the mare owner find another stallion. We have had no problem with one PSSM gene. We have and will share our information with mare owners after we learned the results of our stallions and before they breed their mares in 2012. This is the type of information we need to share. Responsible mare owners will need to test, even without the symptoms. This gene is not confined to one bloodline or family of horses. It is theorized PSSM has been around prior to the discovery of the New Worlds.

We take all of the information available to us and genetic testing is part of our equation. When we choose breeding animals we consider all aspects of the" what ifs". Our breeding program includes decisions from conformation to color. Homozygous color producers are night-blind, themselves, but management of their condition is a possibility. It runs on the color gene and can only be passed on if you breed color to color. We breed solid mares to the colored studs. Rat tailed horses or lack of hair is another inherited trait than can show up when you least expect it. These poor horses that live outside with the flies are tortured. There are so many things to consider when choosing the perfect cross. Poor conformation in general may cause a lifetime of problems, some can be managed with farriers and corrective shoeing.
Just when we get the perfect horse after a lifetime of breeding…along comes another genetic marker. The good news; because one horse is a carrier, it does not mean they will pass it on. Statistically there is a 50% chance of inheriting the gene if half of your breeding equation (stallion or mare) includes one of the hidden genes.

We encourage responsible breeding
We will continue to test and educate ourselves and mare owners. PSSM in particular is a genetic condition that is not precluded to one specific bloodline. We believe testing and sharing as much information available to us at the time gives the mare owner another decision to weigh when comparing to other genetic factors that may not be as manageable; in reference to visible conformation faults.

We encourage good equine management. Breeders need to look at the entire picture and decide which flaws they can live with and which ones they can live without. Early farmers learned to manage the tying up syndrome. Now, we have a test that will give us a headstart with the proper management and will prevent of an occurrence of tying up. Some genetic traits are quite manageable, others can be fatal. I believe PSSM is similar to a predisposition in humans and the animal world to Diabetes2. We know what we must do to prevent the disease as we enter middle age. It is a condition that can be controlled with proper diet years before we see signs of the disease. With the knowledge Science has provided us, as horse owners, we can be more responsible in our care.
There will be new discoveries, and better ways to feed and manage our equine friends that have learned to adapt to a manmade environment. If you are planning to breed, test your mares for the genetic markers available. From this point forward, we have made the commitment that foals from our breeding program will be tested before they go to their new homes. We understand that Science has new discoveries from color factors to hidden genetic markers. We will try to keep up as tests are available and pass them on to you.

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