Over 25 years ago I got a call from Richard, a Quarter horse breeder, who had just moved to a farm a few miles from my place. He had come to Maine from down south and was looking for a vet. We made an appointment, and a week later I backed my truck up to his barn. I slid open the big white barn door and walked in. I didn’t see Richard, so I started walking through the barn to get a feel for his animals. By the time I reached the fourth stall I was starting to think I was in Disneyland. Every single one of his 8 horses was a buckskin. Every one! I have always liked the color, maybe because I don’t see that many, so they always make me look twice. I had never seen a barn full of them.
Richard came into the barn from the house a few minutes later. We introduced ourselves, and I commented on his horses. “Yup, I breed for that. I won’t have a horse that isn’t buckskin. I will tolerate a dun, but they come out any different than that, and they’re gone.” As I listened to him talk about each horse, I realized that he was practicing very close inbreeding so that he could keep getting the color. It was father bred to daughter, sister to brother sort of thing. I have always believed in hybrid vigor, and this was going against that and everything I had ever been taught or read. My trips to his barn were infrequent, and after 2 years he moved away. He felt that there wasn’t a market here for his animals. The fact is that the constant inbreeding was causing all kinds of conformation issues, and us Maineiacs just weren’t buying his nicely colored but deeply flawed horses. Selecting for just one thing was causing big problems. Richard was “color blind”, unable to see beyond the appearance that he wanted. Select for just one thing and sooner or later those recessive genes will come home to roost.
Most of us are drawn to one breed of horse. Maybe it’s the one we grew up with and know. Sometimes we like a particular because that’s the one who’s best at what we like to do. I googled the term “horse activities”, and found 97, running from trail riding to hunting wild boar on horseback (with a spear)! Then I tried “breeds of horses”, and found hundreds worldwide. I got tired trying to count them, so I just counted the breeds whose name starts with A, and found 38! There are actually 6 breeds that start with the word American! All breeds were started by an individual or group of horse people who wanted a horse that would look or perform a certain way. A Belgian weighing close to a ton can plow a field or pull a hay wagon loaded with 50 adults up a hill. Don’t try those things with an American Saddlebred. But that peacock of the horse world can bring a stadium of people to their feet cheering as he prances around the show ring. Each breed has an activity that it does best. The consumer (horse owner) demands the traits and the breeders respond. The term that best describes what is going on here is “Fashion vs Function.”
Let’s look at vehicles for an analogy. You drive the one you have because it fits you and what you need it for. No point in having all wheel drive in Florida unless you like to race in the sand. However, your drive home on a stormy winter nights may require that extra traction. As a consequence we have all kinds of vehicles, fitting every need. If a new need like 50 mpg arises, the need is met, and hybrids start coming down the line. The difference between horses and vehicles is that vehicles are stamped out on an assembly line. The 100th vehicle leaving the line that day is just like the first. Not so with horses. The more you use the same genes the bigger the problem down the road.
As an example of what happens with the “manufacture” of horses, let’s look at the Appaloosa breed. The Nez Pierce Indians found and bred a horse that could handily carry a warrior and be flashy. Lots of white men liked the look of the colored Appys too, and that “blanket” over the hind end became selected for. Whenever one trait is selected for and others are forgotten, other things start to happen, and it usually isn’t good. The result has been a weakness of the Appaloosa eye. Many in the breed suffer from periodic opthalmia which can result in early blindness. There is also a tendency toward night blindness and, way at the other end, an often skimpy tail. It would be GM deciding to make the most incredibly advanced all-wheel drive ever seen, but letting everything else like brakes and safety get shoddy.
There are many more examples of what happens when a narrow set of traits is concentrated on and selected for. The Morgan horse was born in the hills of Vermont to answer the need for a hardy horse able to take the family in a buggy to church and the next day get hooked to till the garden. Maybe that night the teenage boy in the family would throw a saddle on to go visit the pretty girl down the road. Justin Morgan, the foundation sire, was such a horse, and stamped the breed. The old style Morgens are still hardy, and as every vet can tell you they are almost too hardy. Many have metabolic syndrome and have to be kept away from grain or green grass. Some Morgan owners decided to go in another direction and make their horses look and act like Saddlebreds, and the easy keeper trait of the breed has gotten lost in that pursuit.
There are many more Quarter horses than any other breed in the US. Some people like to show them at halter, and for a time it was the extraordinarily muscled horse that took the blue ribbons. In selecting for that one characteristic other things were left behind. The Quarter Horse stud “Impressive” had this quality like none before and threw lots of babies who at birth looked as though they had been lifting weights in the womb. The problem was that other items like feet and legs were ignored, and his descendants had a hard time doing any degree of athletics because there was no foundation to support it. They were also subject to HYPP, a debilitating muscle problem, later proven to be thrown by Impressive.
“Minis” of all breeds are popular, and have enabled owners to have a horse on the property without the need for acres and acres. The prime trait selected for has been small size, and again, things that pop up on the way are often ignored. As a result minis are sometimes born with dwarf characteristics like misshapen joints and heads. They often have dental problems because they get issued the normal number of teeth without enough room to house them all. These recessive traits can surface even if both parents are normal.
Consider the racing Thoroughbred. The fastest Kentucky Derby was run by Secretariat 42 years ago! Every year records are broken in every sport. Granted, Secretariat was exceptional in every way, but there have been improvements in training and tracks since then. The racing thoroughbred has been selected for early speed as a 3 year old. That’s where the money is. You can’t have both early maturity and a long life. Many in the breed are old and creaky in their mid and late teen years. In a northern New England winter it is hard to keep their ribs covered. Thin walled and shelly feet are a common issue, and many have to be shod with glue-ons because they can’t take a nail.
An extreme example of the inbreeding issue leading to recurrent problems is the Fresian breed. They are flashy movers and several Hollywood films have added to their popularity. Demand has meant constant inbreeding which has led to immune problems. They are not the easiest horse to settle when bred and have many more problems associated with foaling than other breeds. Veterinarians dealing with them on a regular basis all have stories of their issues.
Arabians, long noted for their endurance and excellent conformation have suffered dictates from the halter horse group of owners. The unique dished face has been selected for to the point that it is a parody, and there will be a price to be paid in these horses not getting enough air if they are asked to do more than stand around and look pretty. I was sad to see an example of this on the cover of a recent leading Arabian magazine.
If I have not mentioned your breed it is only because this article would get a little tedious. Whenever and wherever animals (all types) are bred and a trait or two is selected for there will be issues. So, what’s to be done? First, I think it is wise to deeply research any breed you are interested in. The official breed web site will rarely mention its genetic problems, even though every breed has them. The breeders themselves are likewise quiet about issues, even though they live with them every day. Dig deep enough and you will find references to them. You may have to do an end run and do a search for a particular problem in the veterinary literature. Usually every such article has a paragraph on predilections which means the breeds that are apt to have the problem. Talk to your vet about his or her experiences with the breed. Before you take possession of a horse, check the pedigree for inbreeding. There is a mathematical way of quantifying this, called the coefficient of inbreeding which can tell you what the risks are. If it’s performance you want, don’t be afraid of the horse of mixed breeding. Like mutts in the dog world they are often healthier and live longer than horses locked into generations of careless breeding.
–David A. Jefferson, DVM