Received: 2021-10-04 | Accepted: 2021-11-29 | Available online: 2021-12-31 https://doi.org/10.15414/afz.2021.24.04.340-344 Grape pomace is a bioactive compound rich winery by-product having antioxidant properties. However, its use in equine nutrition in this regard have been unexploited to date. Thus, this study aimed to investigate whether dried grape pomace (DGP) could enhance the antioxidant mechanisms of horses. Redox status was assessed through glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity in blood serum, and ferric reducing ability of plasma (FRAP). Twelve horses were assigned to three groups recieving a basal diet (control group) or the basal diet supplemented with 200 g of DGP (experimental group 1), or 400 g of DGP (experimental group 2) for 30 days. Dietary DGP supplementation of horses at a level of 200 g positively affected their redox status through increased FRAP (P<0.05). 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