Size
A horse is measured from the ground to the withers (the tip of its shoulders), in units called hands (one hand equals 10.2 cm or 4 in.).
Adult male Clydesdales measure 17 to 19 hands (1.7-1.9 m or 5.7-6.3 ft.). A male's average weight is between 771 to 998 kg (1,700-2,200 lb.).
Adult females measure 16 to 18 hands (1.6-1.7 m or 5.3-5.7 ft.). A female averages 680 to 771 kg (1,500-2,000 lb.).
Body Shape
A horse's body is adapted for speed. Other animals, such as antelope, are as fast as the horse, but not nearly as large.
The Clydesdale is an immensely strong, barrel-chested horse. It was originally bred for hauling and doing farm work.
Coloration
The most common Clydesdale colors are bay (a deep mahogany brown) and brown, though some may be gray, black, or roan (bay with some white hairs). White markings on the face, legs, and sometimes on the body are typical of this breed.
Limbs
Horses are cursorial (adapted for running). They're adapted to a mobile open-country existence.
Specializations of the leg and foot enable these animals to be swift and strong runners.
In the forelegs, the ulna is reduced in size so that all the weight is carried by the radius. The radius and ulna are fused.
In the hind legs, the fibula is reduced in size so that all the weight is supported by the tibia. The tibia and fibula are fused.
Hooves
In odd-toed hoofed mammals, the body's weight is borne on the central or third digit (toe). The main axis of the foot passes through the third digit, which is the longest on all four feet.
In all horses, only the third digit of each foot is functional. The remaining digits are vestigial (reduced and nonfunctioning).
The single functional digit of a horse's foot is completely surrounded by a hoof composed of keratin (a tough, fibrous protein which also composes a human's fingernail). The hooves protect a horse's feet from the terrain.
A horse's stance is known as unguligrade. They walk on their hooves, which are at the tips of the digits, or toes. By contrast, cats have a digitigrade stance (on the toes), and humans have a plantigrade stance (on the soles of the feet).
A horseshoe for a full-grown Clydesdale measures more than 51 cm (22 in.) from end to end and weighs about 2.3 kg (5 lb.). It's more than two times as long and four times as heavy as shoes worn by a riding horse.
To shoe a horse, excess hoof growth is trimmed away. The shoe is then attached to the hoof by eight nails, each 8 to 10 cm (3-4 in.) in length.
Shoes for the hind feet have tips that curve out for additional support and traction, since these feet bear the heaviest load when hauling.
Shoes are reset approximately every six weeks.
Head
The head has a relatively elongated muzzle, providing space for the teeth. A Clydesdale's profile is just slightly convex ("Roman" nose), compared to the more concave profiles of other breeds.
The eyes are well above ground level while the horse is grazing. This provides the horse with a greater area of vision to look out for potential danger.
The ears are exceptionally mobile. A horse can move its ears toward the direction of a sound.
Teeth
Depending upon the breed, horses have 40 to 48 teeth that continually grow throughout their lifetime.
Rear teeth have tablelike surfaces crossed by ridges that form a grinding surface between the upper and lower jaw. The jaw moves in a sweeping side-to-side motion, compared to the more up and down motion of other mammals.
Hair
Horses have two types of hair: the fine and comparatively short hair of the coat, and the coarser and longer hair known as horsehair. The horsehair forms the forelock (hair on forehead), mane, tail, tuft of hair at the back of the fetlock (the lower part of the leg) and the feather (the long white hair found on the Clydesdale's ankle).
Long, coarse bristles about the muzzle and eyes of a horse are generously supplied with nerves and act as delicate organs of touch.
A mane covers the neck, and in the domestic horse it falls to the side. On the only species of wild horse, the Przewalski's horse, it stands erect.
Body Temperature
The body temperature of the Clydesdale is 38°C (101°F).