E53 - Effect of a Supplement Containing Cannabidiol (CBD) on Sedation and Ataxia Scores and Health Parameter

Abstract: Supplements containing cannabidiol (CBD) have recently been introduced into the equine market, but few research studies on their safety have been published. The purpose of this study was to determine if a supplement containing CBD would lead to sedation and/or ataxia or changes in other health parameters after being fed for 56 days. Twenty clinically normal horses were housed in stalls for 56 days of the study. On day -1, prior to treatment, horses underwent physical examinations, blood work (CBC and biochemistry panel) and were scored for sedation and ataxia. Horse were then randomly divided into treatment (CBD, 150 mg in supplement pellets top-dressed on a grain ration once daily [n=10]) and control (CTR; [n=10]) groups. Horses were observed daily and scored weekly for sedation and ataxia, 2 hours after feeding, by 2 masked observers using validated scoring systems. A CBC and biochemical panel were performed on days 28 and 56, 2 hours after administration. The supplement was readily consumed and no adverse effects were observed. Sedation and ataxia scores were near zero in most horses during the weekly exams. There was no treatment effects on blood values, including anemia and blood proteins, liver enzymes, kidney values, or electrolytes and calcium. Body weight significantly increased in all of the horses by day 56 of the study, but a significant treatment by day effect was not observed. The supplement containing CBD (150 mg) did not cause sedation, ataxia or negative effects on health or blood parameters during 56 days of treatment.