Influence of dietary vitamin C and selenium, alone and in combination, on the performance of laying hens and quality of eggs

Two hundred and forty laying hens were fed diets supplemented with vitamin C and selenium (Se). Vitamin C was added at 0 or 200 mg/kg, and Se was added as sodium selenite or selenized yeast at 0.3 mg/kg. The feed intake and egg production were measured, and egg quality parameters were determined. Supplementation of the basal diet with Se significantly increased the laying performance; however, vitamin C significantly decreased feed intake and egg production. Vitamin C increased vitamin E concentration in the yolk. Both selenite and Se-enriched yeast increased the vitamin E concentration in the yolk and the Se concentration in the yolk and albumen. The oxidative stability of yolk lipids was improved in hens fed diets supplemented with sodium selenite, but not in those fed diets supplemented with Se-yeast. After 28 days of storage, however, the beneficial effect of selenite on lipid stability ceased. The supplementation of the basal diet with vitamin C significantly worsened the oxidative stability of yolk lipids, indicating that vitamin C acted as a pro-oxidant. Thus, vitamin C increased the laying performance and influenced some traits of egg quality. The combined supplementation of vitamin C and Se did not prove to be successful.