Vitamin C overcomes the detrimental effect of vanadium on Brown eggshell pigmentation

Phosphorus supplementation from poor quality feed-grade sources may introduce excessive levels of vanadium (V) into the diets of laying hens. Vanadium in the diet of chickens has been shown to be detrimental to egg production, albumen height, BW, and feed consumption. This study showed that dietary V also has a negative effect on the color of brown eggshells from commercial-type layers. Commercial-type brown egg layers were fed a corn-soybean meal basal diet supplemented with 0, 50, or 100 ppm of V as NH4VO3 to determine the effect on shell pigmentation. Hens fed V at both dietary concentrations laid lighter colored eggs (less redness) after only 2 d. Another experimental group of the same type of hens that were fed lower V concentrations (0, 15, or 30 ppm) also had less shell pigmentation. After the detrimental bleaching effect on shell color was observed, these diets were supplemented with 1 of the following: no supplement, 100 ppm of vitamin C, 100 IU of vitamin E, or 100 ppm of beta-carotene. Only vitamin C restored the eggshell color of eggs from hens fed both levels of V. When these same antioxidants were added as preventive agents to diets supplemented with 15 ppm of V before the effects of V were established, brown layers benefited again from 100 ppm of vitamin C but not from vitamin E or beta-carotene.