Background: The chicken egg is one of the nature’s flawlessly preserved biological products, recognized as an excellent source of nutrients for humans. Selenium (Se) is an essential micro-element that plays a key role in biological processes. Organic Se sources have shown many advantages over inorganic Se in poultry and can be produced biologically by microbial reduction of Se. Therefore, the possibility of integrating Se enriched bacteria as a supplement in poultry feed can provide an interesting source of organic Se, thereby increase egg Se concentration, improve oxidative stability and offer health-related advantages to humans. The objective of this study was to examine the effects inorganic and different organic Se sources on egg yolk colour, antioxidant profile, oxidative stability, and storage effect in relation to the treatments for fresh and stored egg yolk at 4±2 0C for 14 days.
Results: The results reveals that dietary Se supplementation, especially the organic (ADS18 > Se-Yeast) sources influence (p < 0.05) egg yolk colour. Dietary inorganic Se and organic Se were noted to significantly improves egg yolk and breast meat antioxidants profile (total carotenoid and phenol content). There was a significant (p < 0.05) decrease in total cholesterol in fresh, stored egg yolk and breast muscle of Se treated groups compared with control. Whereas for breast muscle, only hens with organic Se supplementation (ADS18 > Se-Yeast) showed lower (p < 0.05) cholesterol compared to inorganic and control hens. The oxidative stability parameters of the eggs, breast and thigh muscle, and plasma showed a significant decrease (p < 0.05) in primary oxidation products (MDA) concentrations with hens supplemented with ADS18. However, the MDA content increased (p < 0.05) with an advanced storage period in egg yolk. It should be noted that, compared to inorganic Se and basal diets, egg yolk from hens fed with organic Se remain fresh for 2 weeks.
Conclusions: Dietary Se organic supplementation (ADS18 > Se-Yeast) improves egg yolk colour, antioxidant profile, and oxidative status of egg yolk and tissue. For egg enrichment and antioxidant properties, the source of supplemented organic Se is essential. Thus, ‘’functional eggs’’ enriched with organic selenium becomes possible to produced.