Animals have long been used in therapy. Renowned psychoanalyst Sigmund Freud, who died in 1939, believed dogs helped his patients relax during sessions. Getty Images
A youngster at Sirona Therapeutic Horsemanship in Devon shares a special moment with one of the clinic's five horses. Equine therapy may help people suffering from depression, bipolar disorder, phobias, anger issues and trauma. Courtesy Shaun Derioz
Equine therapy has grown in popularity in the UK in recent years and is now a member of the British Association for Counseling & Psychotherapy (BACP). Courtesy Shaun Derioz
For patients coming from traumatic home lives, the fresh air of the great outdoors and chance to socialize, are just as much a part of the healing process as the horses themselves. Courtesy Shaun Derioz
Anne Romney, the wife of Republican presidential candidate Mitt Romney, helped boost equine therapy's public profile this year when she revealed it helped her overcome depression. Getty Images
British TV celebrity Katie Price, pictured launching a range of equestrian wear, has spoken of the therapeutic benefits of riding horses. Getty Images
Patrick Swayze and wife Lisa Niemi, bred Arabian horses at their multimillion dollar ranch in the San Fernando Valley. The actor, who died in 2009, said the horses offered a relief from Hollywood superficiality. Getty Images
The U.S.'s Jonathan Wentz competes in the dressage event at the London 2012 Paralympics. Many competitors said they became involved in riding as part of their treatment for physical disabilities. Getty Images
Terminally ill patients at a hospice in Colorado enjoy the company of a visiting llama, used to boost morale and wellbeing. Getty Images