Stereotypic behaviors like crib-biting, weaving, and box-walking in horses indicate underlying welfare problems and become self-reinforcing once established.
Stereotypies in horses are behavioral markers of chronic welfare compromise that reflect the mismatch between horses' evolutionary needs and typical stable management. Horses evolved to move continuously and consume fibrous forage throughout the day - instead, many are confined for 20+ hours daily and fed high-concentrate meals. The development of stereotypies represents an attempt to cope with this environment, and the endorphin release associated with crib-biting means the behavior becomes self-reinforcing. Crucially, preventing the stereotypy without addressing its cause removes a coping mechanism without improving welfare and may worsen the horse's emotional state.