Dietary antioxidants in young swine

Young swine obtained by hysterectomy were fed purified diets low in vitamin E and supplemented with d-α-tocopheryl acetate and ethoxyquin (Santoquin^R). It was demonstrated that with very low levels of polyunsaturated fatty acids (PUFA) in the diet, both tocopherol and Santoquin protected the tissues of the pig from increased thiobarbituric acid (TBA) values and from increased hemolysis usually associated with low vitamin E status. When the dietary PUFA were increased to levels over 5%, the supplements of tocopherol and Santoquin protected against increased TBA values of tissue homogenates, but not against increased hemolysis of erythrocytes, even when blood serum showed substantial amounts of tocopherol. Some of the interrelationships of dietary PUFA and α-tocopherol were demonstrated. It was shown that for each 1% of peroxidized corn oil added to the diet above 4%, roughly 100 mg of d-α-tocopheryl acetate was necessary to protect the pigs from erythrocyte hemolysis. The failure to reach a “zero” TBA value in vitamin E-deficient swine tissue homogenates substantiated the theory ofin vivo lipid autoxidation, and the increased TBA values of incubated tissue homogenates demonstratedin vitro lipid autoxidation in tissues not protected by a biological antioxidant. Presented at the AOCS meeting in Toronto, Canada, 1962. Supported by grants from the Monsanto Chemical Co., St. Louis, Mo., and The Hormel Foundation.