Injectable all rac-α-tocopherol, at a dose of 12.4 IU/kg body mass, increased circulating levels of α-tocopherol in the black rhinoceros (Bicornis diceros) from 0.18 μg/ml to 1.47 μg/ml within 2 hr. Although the plasma level peaked at Day one (13.07 μg/ml) and dropped rapidly, substantial residual effects were seen even 10 days (1.50 μg/ml) following a single injection. It appears that parenteral vitamin E administration may be suitable for therapeutic treatment of vitamin E deficiency in the black rhinoceros.