Two different doses of a natural extract titrated in phenylpropanoid glycosides (PPGs) were evaluated for their effect on blood parameters and plasma oxidative status in pairs of intensively reared Italian hares. The study lasted 210 days, during which 45 couples of hares were divided into three homogeneous groups. A control group (CON) was fed a control diet while the two experimental groups were fed a diet supplemented with 1 or 2 kg/t of a supplement titrated in PPGs. Blood samples were obtained at 0 d, 70 d, 140 d and 210 d and assayed for plasma lipid profiles, bilirubin, haematological parameters and indicators of oxidative status (Reactive Oxigen Metabolite (ROMs), Thiobarbituric Acid Reactive Substances (TBARS), vitamin A and E). Although the dietary treatment did affect levels of triglycerides, total cholesterol and total bilirubin, which all decreased markedly (P<0.05), while significantly increasing (P<0.01) HDL cholesterol values. The dietary treatment also significantly improved the oxidative status of the blood, which displayed an increase in both vitamin E (P<0.01) and vitamin A (P<0.05) and a decrease in ROMs (P<0.01) and TBARS (P<0.05). The improvements in the blood parameters, lipid profile and plasma oxidative status continued to increase significantly as the trial progressed, indicating a positive effect with increased length of treatment. The results of this study demonstrate an important role for feed supplementation with respect to antioxidant activity on some blood parameters, including the lipid profile and the oxidative status of blood.