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Horses have been central to human transportation and agriculture for centuries. These symbols of strength and speed require hoof care and new shoes every four to six weeks to stay on the job. But why?
Horses (Equus caballus) that are domesticated for human use and selectively bred for performance wear shoes because their feet are delicate and therefore need protection, he said. Dr Fernanda Camargo (opens in new tab), a veterinarian and equine extension agent at the University of Kentucky. “Shoes provide protection for some areas of the foot of the horse“, Camargo told Live Science via email. “They prevent the hooves from wearing too much and thus becoming sensitive.”
The outside of the hull, known as the wall, is made of a horn-like material that grows continuously and needs to be trimmed, just like a person’s fingernails, according to University of Missouri Extension (opens in new tab). “Shoes also help the foot maintain proper shape,” Camargo said.
However, rough terrain such as sand and rocks can wear away the exterior, exposing the sensitive inner hull. Then the horse feels pain and may not be able to walk. Historically, such deficiencies would have prevented the horses from being used on the battlefields or during harvesting, so horseshoes were added to reinforce the hoof wall, Camargo said.
It is estimated that horses have worn some type of horseshoe since they were domesticated. 6000 years ago (opens in new tab)Camargo said.
Related: Why do we still measure things in horsepower?
Originally, horseshoes were made from leather or plant material. Metal shoes nailed to horses’ feet were first used around 500 AD and became commonplace over the next 500 years, Camargo said. While aluminum and steel shoes nailed to the hull are still the most common, she said, a variety of other materials – such as rubber, resin and plastic – can also be nailed or glued to the hull like a horseshoe.
While many horses need shoes, not all do; it depends on the type of riding, the terrain and the frequency with which the horse is ridden. Those riding on rocky or concrete terrain are more likely to need shoes. Even horses that are not ridden may need shoes to protect them from the terrain or therapeutic shoes to help manage a foot condition. But “many horses that are ridden here and there, and are kept on grassy/not hard ground, will do fine without shoes, with regular visits from farriers,” Camargo said.
Wild mustangs, on the other hand, don’t wear shoes and can move over rough terrain because they have very strong feet, Camargo said. But their hooves can still wear down and cause lameness. If that happens, it will cost a mustang its life, she said.
Some people wonder if nailing horseshoes to a horse’s hoof hurts them. There is not blood veins or nerves in the hoof wall, according to University of Missouri Extension, so if the shoe is nailed in correctly, it’s not painful. “But inappropriate shoes can hurt,” said Camargo. If the shoes or nails are misplaced, if the shoes are the wrong shape or size, or if the farrier applies pressure in the wrong areas, they can injure the horse. And if the hooves are poorly trimmed beforehand, it can cause pain or lameness with or without horseshoes, she said.
