Interaction of Zinc and Vitamin E in the Chick 1

Summary

Chicks fed a low zinc diet (5 ppm) based on soybean protein, cornstarch, and corn oil developed severe skin lesions on the toes and foot pads as well as gross joint abnormalities that severely impaired locomotion. Incubation of foot skin in a peroxidative buffer containing 5 ppm Cu resulted in the release of malon-dialdehyde or other thiobarbituric acid reactive substances. The rate of release from skin or zinc deficient chicks was 4-5 times as great as from skin of controls fed adequate zinc. Supplementation of the zinc deficient diet with fat soluble antioxidants, particularly vitamin E, decreased the severity of the skin and joint pathology. High levels of dietary vitamin E also decreased the rate of release of peroxidative products from zinc-deficient skin but had no effect on control skin. The results show a significant physiological interaction between dietary vitamin E and zinc. It appears that cells from zinc-deficient chicks can benefit from incorporating higher than normal levels of vitamin E into their membrane structure. It is postulated that zinc protects against peroxidative damage and promotes membrane integrity.