Equine conformation

Equine conformation evaluates the degree of correctness of a horse's bone structure, musculature, and its body proportions in relation to each other. Undesirable conformation can limit the ability to perform a specific task. Although there are several universal "faults," a horse's conformation is usually judged by what its intended use may be. Thus "form to function" is one of the first set of traits considered in judging conformation. A horse with poor form for a Grand Prix show jumper could have excellent conformation for a World Champion cutting horse, or to be a champion draft horse. Every horse has good and bad points of its conformation and many horses (including Olympic caliber horses) excel even with conformation faults.

The standard of the ideal head varies dramatically from breed to breed based on a mixture of the role the horse is bred for and what breeders, owners and enthusiasts find appealing. Breed standards frequently cite large eyes, a broad forehead and a dry head-to-neck connection as important to correctness about the head. Traditionally, the length of head as measured from poll to upper lip should be two-thirds the length of the neck topline (measured from poll to withers). Presumably, the construction of the horse's head influences its breathing, though there are few studies to support this. Historically, a width of 4 fingers or 7.2 cm was associated with an unrestricted airflow and greater endurance. However, a study in 2000 which compared the intermandibular width-to-size ratio of Thoroughbreds with their racing success showed this to be untrue. The relationship between head conformation and performance are not well-understood, and an appealing head may be more a matter of marketability than performance. Among mammals, morphology of the head often plays a role in temperature regulation. Many ungulates have a specialized network of blood vessels called the carotid rete, which keeps the brain cool while the body temperature rises during exercise. Horses lack a carotid rete and instead use their sinuses to cool blood around the brain. These factors suggest that the conformation of a horse's head influences its ability to regulate temperature.

Straight, upright, or vertical shoulder

Laid-back or sloping shoulder

The Humerus (a.k.a. the arm bone)

The arm bone is from the point of shoulder to the elbow, it is covered in heavy muscle and serves as a leverage point for the muscle of the front leg attached near the elbow.

"Ideal"

Conformation of the Ideal Humerus (all measurements are while the horse is standing squarely)

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