Study of lycopene supplementation on carotenoid and lipid parameters of laying hens and investigation the deposition into egg yolk

More then 600 carotenoids are responsible for yellow or reddish coloration of plants and animals. Beside the coloration these molecules have special metabolic effects in plants and animals, as well. Carotenoids occur in the skin, ovary, liver and eyes, but the different types are distributed in a characteristic way in the various tissues. Birds, as all of animals metabolize carotenoids, but they are not able to synthesize these molecules. For these reason birds require carotenoids in their food. The oxygen containing carotenoids, the xanthophylls are deposited into feather, skin and egg yolk of birds. This feature of xanthophylls is used in the animal husbandry for the desired coloration of egg yolk. Lycopene is an acyclic hydrocarbon carotenoid which stains the tomato red. Lycopene has a lot of health benefit as antioxidant, cell cycle modulator; it has hypocholesterolemic and anticarcinogenic activity especially in prostate cancer. This carotenoid is not a common constituent of poultry fodder. In the present experiment after two weeks carotenoid depletion period Hy-Line Brown laying hens were supplied with two doses of lycopene (group L-5 250, group L-10 500 mu g/kg fodder) by Redivivo (TM) (DSM) for four weeks. Layers consumed carotenoid free diet assigned for controls (group L-0). Egg yolk colours were estimated by CIELab scale, serum and yolk samples were analysed for lycopene by HPLC, and some lipid parameters (cholesterol, HDL-cholesterol, triglycerides) by enzymatic colorimetric tests. The lycopene supplementation resulted high CIELab a* values (L-5 19, L-10 17.5) compared to L-0 (5.2) (p<0,001). The lycopene accumulation into egg was 80-100 mu g/yolk. The serum cholesterol concentration is decreased in group L-10 (p<0.05). The results indicate that dietary lycopene can be accumulated into yolk, resulting the desired colour. Taking into account the health benefits, lycopene enriched egg may be a candidate for functional food.