Horseshoe

A horseshoe is a U-shaped piece of iron, rubber, plastic, rawhide or a laminate of these, nailed or glued to the hooves of horses and some other draught animals--like a shoe. They are used to protect the animal's hooves from wear and tear. more...

Early horseshoes had "calkins" or protruding tabs at the ends of the shoe to provide additional traction (these are still used on some competition horses in sports like team penning). Kept as a talisman, horseshoes are said to bring luck. Horseshoes are also used for a popular game, horseshoes.

The horseshoe seems to have been introduced to Western culture by the Greeks in the 4th Century. Horseshoes are available in a wide variety of materials and styles, developed for different types of horses and the work they do. Common materials are steel, aluminum and plastic, and some specialized shoes are made from magnesium, titanium or copper.

Reasons for use in domestic environment

The traditional point of view

Since the early history of the domestication and use of horses, many factors have contributed to the need for the bottoms of domestic horses' feet (hooves) to have additional protection over and above their natural hardness.

Less healthy food

Live grasses, weeds and shrubs, which are eaten in the wild, are high in nutrients such as beta carotene. Cultivated feeds lose a high proportion of their carotene within hours of harvesting and so do not provide this vital ingredient to the horse. The hoof is made of horn, much as the human fingernail, and grows hard, tough and flexible only with optimal nutrition.

Less varied terrain

Horseshoes are not needed in nature as the horse walks and grazes continuously over a wide variety of surfaces. The consequence of this nonstop travel on the horse's feet is to keep them worn to a small, smooth, even and hard state. The continual stimulation and irritation of the sole of the foot keeps it thick and hard, much like a callus. However, in domestication, the customary amount of ground covered by a horse on a daily basis is greatly reduced. Therefore, the hooves harden much less and are more vulnerable to injury.

Added weight

Horses' hooves can become quite worn out when subjected to the added weight/stress of a human, pack loads, cart or wagon traces.

Wetter climate

Horses have moved from the more arid steppes to the wetter climate of northern Europe. This wetter climate and heavy soils softened the hooves and made them prone to splitting, making hoof protection necessary, and consequently it was in northern Europe that the first practical horseshoe arose.

Exposure to ammonia

The hooves of horses that are kept in stalls or small turnouts are constantly exposed to ammonia from urine. The hoof capsule is mostly made from keratin, a protein, and is weakened by this exposure. Wearing shoes does not prevent or reduce damage from ammonia exposure. Rather, they are meant to reduce wear on weakened hooves.

Consequences of less healthy hooves

In captivity, absent the natural conditioning factors present in the wild, the feet of horses grow overly large, long, fragile and soft. Hence, protection from rocks, pebbles and hard, uneven surfaces is lacking. Cracks in overgrown and overly brittle hoof walls are a constant danger, as is bruising of the soft tissues within the foot because of inadequately thick and hard sole material.

Corrective shoeing

The shape, weight, and thickness of a horseshoe can significantly affect the horse's gait. Farriers trained in hot shoeing can make custom shoes to help horses with bone or musculature problems in their legs.

Traction

Traction devices such as borium for ice, studs for muddy or slick conditions, calks, and rims are useful for performance horses such as eventers, show jumpers, polo ponies, and other horses that perform at high speeds, over changing terrain, or in less-than-ideal footing.

Gait Manipulation

Some breeds such as the Saddlebred, Tennessee Walking Horse, and other gaited horses are judged on their high-stepping movement. Special shoeing can help enhance their natural movement.

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