Stereotypies or stable vices in horses including crib-biting and weaving indicate past or current welfare deprivation and require environmental improvement rather than punishment or physical prevention.
Stereotypies develop as coping mechanisms in response to welfare deprivation, most commonly limited forage access, social isolation, or confinement frustration. Once established they indicate a history of welfare compromise even if current conditions are improved. Physical devices that prevent stereotypies block the coping mechanism without improving welfare. The appropriate response to stereotypies is to identify and address the underlying welfare deficit rather than suppress the symptom.