Conformation Determines a Horse’s Usefulness and Comfort

Conformation is a major factor in the physical soundness of a horse. Poor conformation can lead to problems related to concussion. Concussion is the force that travels up the leg each time the hoof hits the ground and if excessive, leads to injuries and conditions such as ringbone (a disease of the pastern joints). Poor conformation also leads to gait abnormalities (the leg or legs do not travel in a straight line) and gait interference (the legs hit each other in movement).

Very few horses have perfect conformation. Conformation also varies with breed, within a breed and between individuals. Some conformation faults are not serious and others will affect one activity more than another. Unless you want to compete at the top level, most horses can do most activities within reason. As the horse develops and is trained, the stronger muscles will carry the animal better and this can override, to some extent, milder conformation faults.

Assessing conformation

To assess conformation, stand the horse on a level surface with someone holding the head, but allowing the horse to stand with its head at the natural height. On first appraisal, a horse with good conformation should:

• Be symmetrical from all angles. Walk around the horse to assess this.
• Be able to stand square. With a little pushing backwards and forwards the horse should be able to stand with all four legs coming straight down from the body to the ground.
• Be in proportion. For example, the head should look in proportion to the rest of the horse, not too large or small. The front end of the horse should not be too small or large for the back end.

Neck

The neck can be too short or too long, too thick or too thin. Minor imperfections can often be improved with work; for example, a thin neck will improve as it develops fat and muscle. A short, thick neck is difficult to change, but as long as the horse is not required to work collected (i.e., the higher levels of dressage) then it may not be a problem.

In ewe-necked horses, the neck dips rather than curves up at the crest and is a conformation fault. Correct work will improve a ewe-neck, but will not eliminate it. A horse with this problem will be difficult to ride in a collected frame.

A swan neck is arched at the top and dips in front of the withers. Again, correct work will improve but not eliminate the problem.

Parrot mouth/overshot jaw describes conformation in which the lower jaw is set back. In a mild case, the horse is usually unaffected, but in a more severe case the horse is unable to graze properly because the front teeth (incisors) do not meet to clip the grass. These horses often ingest dirt as they try to graze. In addition, the upper and lower incisors do not wear each other down as they would in a normal mouth, and the molars develop hooks because they are out of alignment. Therefore the horse needs more frequent attention by a dentist.

Sow mouth/undershot jaw is the opposite of parrot mouth. The lower jaw is set forward from the top jaw. It is not as common as parrot mouth and horses with this condition also require extra care with feeding and dental attention.

Head

Facial shape may be a fault in some breeds. A draught horse is expected to have a roman nose, while an Arabian is expected to have a dished face. If a horse’s face is too dished it can affect the breathing.

The head should be well set on. The neck should taper towards the top and join the head in a way that allows the horse to flex the head in and out. Draught horses tend to be thicker through the jowls than other breeds, but should still be able to flex the head to some extent.

The head can be too big or too small. A large head is more common than an undersized one and results in the horse having problems with balance, particularly when working in a collected frame. Correct work will improve imbalance by strengthening the muscles of the neck and back.

Thorax

The withers should be neither too low nor too high. Low withers tend to shift the centre of gravity forward and the saddle will also tend to move forward, which can cause soreness. Horses that have very high withers usually require a custom-made saddle.

The shoulder should be sloping, which is believed to give the horse a longer stride. Heavier horses (draught types) tend to have more upright shoulders. The slope of the shoulder usually corresponds to the slope of the pasterns. If the shoulder is upright rather than sloping, it will tend to suffer more concussion-related injuries and therefore speed work on hard surfaces should be limited.

The girth should be deep to allow room for the lungs and heart. The ribs should be well sprung (i.e., wide as opposed to flat) to give the lungs room to expand. The chest should be neither too narrow (which tends to lead to leg interference) nor too wide. Very wide-chested horses tend to roll as they move, which can be uncomfortable for the rider. The coupling where the loins join the croup at the sacroiliac joint should be smooth and well muscled. Horses that have old sacroiliac ligament damage may have enlargements on either side of the spine at the highest point of the rump.

Back

The horse’s back should be reasonably short and strong. A short back tends to be stronger than a long back and draught horses are naturally short in the back for power. However, if the back is too short the horse is more likely to forge, or hit its front hooves with its back hooves while moving.

In a roach back, the spine curves upwards in the loin area. Unless this is very pronounced, it is not usually a problem. It is certainly preferable to a sway back and is more likely to affect a horse used for riding than one used for driving. Despite the potential for saddle-fit problems, some sway-backed horses do very well.

A straight back is a back that is straight from the withers to the point of the croup. Straight-backed horses tend to be uncomfortable to ride because of being rather rigid. It is, however, a strong back and is not as much a fault in a driving horse as in a riding horse.

Hindquarters

The hindquarters should be well muscled, powerful and symmetrical when viewed from behind. Lean, long muscles are good for endurance as opposed to bulky muscles that are good for power. If you were to compare a top endurance horse (usually an Arabian) with a top Quarter Horse (cutting bred), they would be very different in their hindquarters. The Arabian would have long, lean muscles whereas the Quarter Horse would have short, bulky muscles, yet both horses would be in top condition.

The horse should be as long as possible from the point of the hip to the point of the buttock. Most good racehorses (Thoroughbreds) are long in this area. The horse should also be long from the hip to the hock and short from the hock to the floor. In other words, the hocks should be low to the ground.

The hindquarters are the powerhouse for the rest of the body, so it is important that they are correct and strong. The slope of the croup varies between breeds and individual horses. Arabs and Thoroughbreds tend to have a flatter croup whereas driving/draught breeds are more sloping. Flatter croups are supposed to indicate galloping speed in a horse, and sloping croups are more powerful for pushing/pulling and jumping. Many top-level show jumpers have quite sloping croups.

Legs

Because the horse’s legs are so important in locomotion, serious conformation faults of the legs may severely limit a horse’s usefulness and soundness. See separate articles for details on leg conformation faults in horses.

This article is adapted, with permission, from Horse Sense—The Guide to Horse Care in Australia and New Zealand, second edition (2004).