1989 Volume 42 Issue 3 Pages 161-165
Changes in level of serum and red blood cell tocopherol, and serum vitamin A (retinol and retinyl palmitate) after oral administration of vitamin AD3E premix were examined in calves and milk cattle of the Holstein Breed.
In the calves to which 2, 5000, 000 IU of vitamin A were administered, serum vitamin A levels increased markedly from two to 48 hours after the administration. Serum tocopherol level was not increased by the administration of 1, 000 IU of vitamin E. However, makred increase of the tocopherol levels was observed from eight to 72 hours after the administration of 2, 000 and 2, 500 IU.
In the milk cattle administered with 7, 500, 000 IU of vitamin A, serum vitamin A levels incresed markedly from two to 48 hours after the administration. Although tocopherol levels (in serum and red blood cell) did not increase after the administration of 3, 000 IU of vitamin E, marked increase of the tocopherol levels was observed from 24 to 72 hours after the administration of 6, 000 and 7, 500 IU of vitamin E.
From the findings described above, the effective oral dose of vitamin E for cattle was considered to be about 25 IU/kg for calves and about 12.5 IU/kg for milk cattle.