Equine-assisted services: an overview of current scientific contributions on efficacy and outcomes on humans and horses

The review provides an overview of the current literature concerning the use of horses in equine-assisted services (EAS) and of their effects on humans, and it focuses on their effects on horses. The scientific contributions on EAS are discussed and it is underlined the need to monitor the ability of horses to cope with stress conditions during activity in order to maintain and enhance their welfare. The changes of hypothalamus-pituitary-adrenal axis’ hormones and of total and free iodothyronines during therapeutic riding are presented and critically discussed. The hypothesis of the utilization of triiodothyronine (T₃) and free triiodothyronine (fT₃) as markers to assess the mental stress of therapeutic horses during EAS is presented.