The influence of dietary ethoxyquin on the vitamin E status in broilers.

In a feeding experiment with 48 male broiler chickens was the effect of dietary ethoxyquin and dl-alpha-tocopherol acetate on vitamin E status of chickens investigated. The experimental diets were offered the chickens from the first day of age until the end of the experiment at 42 days. Chickens were fed on diets containing 0, 75, or 150 mg ethoxyquin/kg feed, with (30 mg/kg feed) or without added dl-alpha-tocopherol acetate. The concentration of alpha-tocopherol in plasma of chickens on dl-alpha-tocopherol acetate supplemented diets were significantly higher than those of chickens fed on the nonsupplemented diets. Supplementation with alpha-tocopherol acetate reduced the haemolysis in vitro. Ethoxyquin seemed to have an increasing effect on the concentration of alpha-tocopherol in plasma, but not in the liver. Addition of ethoxyquin to diets without dl-tocopherol acetate reduced the concentration of gamma-tocopherol in plasma. Significant interactions between the addition of ethoxyquin and the addition of dl-alpha-tocopherol acetate to the feed were observed on the haemolysis in vitro and the activity of glutathione peroxidase in plasma. The results indicate that incorporation of ethoxyquin in the diets of chickens exert an improving effect on the vitamin E status of the organism.