Increases in plasma tocopherol concentrations were compared in sheep after a single oral administration of (per kg body-weight): 67 mg D- and 91 mg DL-epimers of alpha-tocopherol, and 74 mg D- and 100 mg DL-epimers of alpha-tocopheryl acetate, or intravenous administration of DL-alpha-tocopherol and DL-epimers of DL-alpha-tocopheryl acetate. 2. The results showed that biological availability was higher after D-alpha-tocopherol dosing than after the other forms. Intravenous administration of D-alpha-tocopherol acetate was a more effective way of dosing in sheep than equivalent intravenous amounts of DL-alpha-tocopheryl acetate or DL-alpha-tocopherol.