Differential effects of high dietary levels of vitamin A on the vitamin E-selenium nutrition of young and adult chickens.

Experiments were conducted to determine the nature of the interaction of high levels of vitamin A and vitamin E-selenium nutrition in the chicken. Results showed that chicks were protected from the vitamin E-selenium deficiency disease exudative diathesis (ED) by a high dietary level of vitamin A (1.0 X 10(6) IU/kg) which moderately depressed growth. A greater concentration (1.5 X 10(6) IU/kg) of vitamin A in the diets of hens fed a low vitamin E diet hastened their depletion of plasma tocopherols and increased plasma glutathione peroxidase (GSH-px) activity. At hatching the progeny of vitamin A-fed hens were severely depleted of plasma tocopherols but had normal plasma GSH-px activities. They showed increased susceptibility to ED when fed selenium-deficient, vitamin E-free diets for 2 weeks. Absorption studies using ligated duodenal loops or oral doses indicated that high-level dietary vitamin A promoted the enteric absorption of selenium but interfered with the absorption of vitamin E. The dual nature of these effects was related to the ED-protective influence of vitamin A when fed to chicks, and the ED-stimulative influence on progeny when vitamin A was fed to dams.