Zylkene® Equine Calming Supplement Rs a behavior supplement that helps horses relax, adapt to new environments, and cope with challenging situations — without sedation. Zylkene Equine is a specially formulated calming supplement that works with the horse’s body to provide a sense of relaxation and contentment. Box of 20. Apple flavored. When to use Zylkene: Loading and travel Veterinary visits Farrier visits New training procedures Stall rest New environments Social regrouping Weaning Our formula contains natural, bovine-sourced, lactose-free hydrolyzed milk protein commonly known as alpha-casozepine. This active ingredient has unique relaxation properties that help to reduce stress caused by situational and environmental changes. *CONTAINS NO PROHIBITED SUBSTANCES. Review the regulations for the competition you are participating in for specific rules.