Stabling horses often suits our needs as people (e.g., convenience), not the horses. Horses are social, herd animals and we know that they are not meant to live alone. Isolation and confinement suppress their natural instincts for friends, forage and freedom . Many of today’s top horse athletes are kept in confined stable areas of approximately 12 square metres. Stabled sometimes for 23 hours a day, this can lead to chronic stress and altered behaviours. Some horses may exhibit learned helplessness to deal with their boredom, frustration, and loss of agency. The gold standard guide for assessing horse welfare is “The Five Domains”. This considers nutrition, environment, health, and behavioural interactions, all of which influence the mental state of the horse. The RSPCA acknowledges that there may be occasions where stabling horses is necessary, or unavoidable e.g., under veterinary direction.
When horses are able to exhibit their natural behaviour, they will rest and graze near each other (for up to 16 hours a day), groom and play, and in the wild, they can travel up to 25 kms a day . Confinement and isolation takes away their freedom of choice for movement, expressing natural behaviours such as lying and rolling, grazing pasture and prevents them from exhibiting herd behaviours . If given the choice, horses will not dwell near their faeces and urine; however, in stables they are unable to avoid their manure due to minimal available space. Horses have four different stages of sleep, one of them is REM sleep, where horses need to be lying, with their head rested on the ground, supported. Horses will be in REM sleep anywhere from 30 to 70 minutes every day. They can manage without this for several days, but they will eventually need to lie down. Group housing and space are important for this to be possible. Horses will exhibit more lying if they are in a herd as this gives them more protection from predators . It has also been shown that stabled horses that are experiencing poor welfare may display more negative behaviours when being ridden and an increased tendency toward aggression .
Some important social actions are mutual grooming and playing together; standing together with a friend in the shade, nose to tail during hot weather, so their tails can flick the flies away from their faces; or when in cold, wet weather standing close and using their bodies to keep each other warm. They build strong bonds with certain horses in the herd, and it is a remarkable testament to their adaptability that so many seem to cope (at least to a certain extent) with the loss of freedom and the isolation they may be experiencing. Many people will confine a horse to a stable as an attempt to provide protection from injury and shelter, as well as to keep them at close hand. However, studies have shown that when a group of horses is turned out (moved to a pasture or field) in a domestic setting, the chances of injury are low. This is especially the case where horses have enough food on which to forage, shelter, space and water to negate the need to compete with their companions over resources . Foals require socialisation from a young age to develop their social behaviours with other horses 
Horses have evolved to meet their nutritional needs by consuming small amounts of forage regularly throughout the day (grazing behaviour). In nature, horses will spend approximately 60% of their time grazing. In comparison, stabled horses typically spend just 15% of their time feeding . Smaller and more frequent meals can reduce the occurrence of stereotypic behaviours (wind sucking, crib biting, pacing), and promote greater digestibility, obesity control, and less risk of developing metabolic diseases related to insulin resistance, as well as reducing the risk of colic, stress severity, and associated diseases . The RSPCA recommends that horses should have access to grazing and pasture as much as possible. If horses must be confined, then pasture access should be equal to, or more than the time horses are in their stables. If stabling is necessary or unavoidable, then it is recommended that “slow” or “trickle” feeding systems are used to maximise the amount of time a horse spends consuming roughage .
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