I've heard this term down at the stable but no one can give me a decent answer. What exactly does mutton backed mean? And why does everyone seem to think it is bad.

A mutton withered horse is one with a very round back, particularly at the withers where the saddle bars contact. The withers of a horse go between the bars of the saddle at the front (pommel) and between the swells. A properly built horse and well fitting saddle will keep the saddle from shifting left and right or too far forward. If a horse has a low wither, or a mutton back, that area is rounded and won't help the saddle stay put at all. Think of any saddle rack and how they have a pitch with a point like a roof. This is somewhat how a horse's withers should be. A mutton withered horse is more like trying to keep a saddle on a barrel. You will at best have to keep the cinch much tighter, and at worst, have a saddle that won't stay put.
It is indeed an undesirable flaw, but not terrible depending on what the animal is to be used for. For example, if you are needing to rope off of a horse, then mutton withers are a fatal flaw. If you just want to trail ride (not in very rough mountain type country) then it's probably not a big deal. I would certainly advise someone with a mutton withered horse to use a breast collar of some sort to help keep the saddle from rolling. Mules and certain breeds of horse tend to be this way. Most two year olds are also this way and built downhill to make it worse. They generally grow out of it in the Spring of their three year old year. Horses that are too fat will also tend to be mutton withered, but the worst offenders are usually just built that way. Hope that helps.

???? Did that help?

You're welcome....

This has become more and more common in quarter horses as of late, at least in my opinion. Mostly it comes from breeding horses for a particular activity without regard for their general conformation. Sheep have no withers, thus the term mutton backed.

I'd have to disagree with you on this becoming more prevalent, jstevens, at least in QHs. Remember the old bulldog style horses that founded the breed, like "Wimpy"? That was a mutton backed style horse, and I still hate riding that style of horse. I'll grant you that I don't ride the full spectrum of QHs, but among the cutters and ranch type horses, this is generally not a problem, as these type horses NEED a good set of withers.

Remember when they say things like we've bred the legs off of race horses and such, that what those in the biz really do is breed winners to winners in hopes of improving the breed. Nobody is out there trying to breed the smallest bones to the smallest bones, or searching for the lowest withers (though the West plsr guys sure seem to like em built downhill), and reputable breeders spend a great deal of time and hard work doing their level best to improve the breed.
IMO, the problem lies with old Jim down the road with that buckskin stud who'll breed any and every mare for $200. And let's not forget those who think that color is the sole factor to look for when looking for a horse. Regarding the "color" breeds, I'd have to agree with you, since so many breeders are only worried about color, the rest is definitely neglected.

Daniel,
That was a very clear and well thought out description. Thanks for posting.

Actually the Quarter horse association has moved away from mutton withered horses, I attribute this to the race horse industry. When the Race horse folks stepped in and made the quarter horse races so popular, and the breed changed with the influx of the Throughbred blood and we went to the "Running Quarter", it was a good move and the quarter horse is the no. 1 horse in the world today. The horse by which all others are judged.

From that came a horse that is level on top, fast and leaner. He is actually about 1/8 quarter and 7/8s Throughbred..The type of horse used in rodeos for roping events etc.

Then cutting horse people refined this horse or downsized him I guess to a animal that may tend to slope down from the hips and had a little Less wither, but not mutton withered by any means, he is sloped down so that he can get under himself,

soooo, we have two types of quarter horses now, and both perform their respective jobs and they flow over into each others diciplines very well. Both have withers enough to hold a saddle and thats the point.

So if you have a mutton backed horse already and want to fit a saddle on it what do you do?

Sorry I don't mean to hijack but I do have one that is a great horse will do anything go anywhere and is willing in every way and not spooky anybody can ride trails, ranch sort or run barrels on her but we are having one hell of a time fitting a saddle on her. She is wide at the shoulders and round backed (no withers), a little short backed too.
Any suggestions?

Snellstrom, Try a mule saddle it worked on my
friends witherless four legged friend. Most mules are lacking good withers {THERE ARE ECEPTIONS) But remember any horse without good withers will allow much easier the saddle to roll around causing the horse to gald.

The mule saddle is a good idea. Also, don't use too thick of a pad, cause that only makes the situation worse. I'd darn sure have a breast collar on one like that all the time. You may also want to look at your saddle, or talk a saddle maker. The width, as well as the angle of bars of the saddle tree can be made/ordered to fit just about any animal. Full QH bars are the widest, as far as I know, and a saddle with wider and flatter bars would be the ticket on a mutton withered horse. That is also how mule saddles are made.