A Tragedy in the Horse Barn

This is Missy, an American Quarter Horse. She is the second horse we acquired when we moved to the farm. She was bought as Kate's first horse and served her well for the first 2 years while Kate gained her confidence and learned to ride. Kate has since moved on to Jazz and Missy has become our dependable, anyone-can-ride horse for guests. She is definitely our best quality mare, pedigree and conformation wise, and by far our largest horse. She is HUGE; 15.2 H tall, with big bones and bulky muscles. In the spring of 2006, Ted decided he would breed Missy to a stallion of his choice and keep the baby for himself. Ted picked Conclusive Mister ( below) a champion halter stallion. He is an (American Paint Horse) APHA buckskin overo. What a handsome guy!



Overo is a color pattern. Those beautiful white blotches on Conclusive Mister's body are caused by the Lethal White Overo color gene. It is called that because if a horse is heterozygous for the LWO gene, ( has 1 copy of the gene from 1 parent), it will usually have the spot pattern, but if it is homozygous for the gene, ( has 2 copies of the gene, 1 from each parent), it will be a Lethal White - a totally white foal with a deformed digestive tract that will die within hours of birth. In this case, homozygosity is 100% lethal. This is usually no problem because breeders simply breed LWO carriers to non carriers. If you remember your high school biology, you can only get homozygosity if BOTH parents carry the gene. However, even if you do breed two LWO carriers together, you only have a 25% chance of producing a lethal white foal. ( remember Punnett squares?)



Well, what we didn't know is that Missy, our beautiful solid bay quarter horse, is "secretly" a "Paint" and carries the LWO gene. We found this out one sad May night, when Missy produced a beautiful, but pure white colt. We were simply shocked and heart broken. Lethal Whites are born perfectly healthy, but once they start to ingest milk, become colicky and eventually die. Within hours of birth, this sad little boy began to have gut pain and gastric discharge out of his nose, proof that he was indeed a lethal white foal. We had him euthanized that day. His name was Casper.


Well, once we were over the shock, we had to decide what to do. In our breeding contract with Conclusive Mister, we have what's called a "live foal guarantee." That means that the stallion owners owed us another breeding for free. The problem is, we couldn't re breed Missy and risk producing another lethal white foal. We had no other mare with the right type of pedigree. So we started searching for a broodmare to substitute. My vet recommended an older mare she knew was for sale. I'll tell her story in my next post!