Anotace:
The aim of this study was to assess the effects of four types of selenium (Se) feed supplements on the indicators of the oxidative stability of egg yolk. A total of 1,740 Bovans Brown laying hens were divided into 4 experimental and 1 control group. The diets fed to the experimental groups were supplemented with 0.2 mg/kg of Se, provided as sodium selenite, Se-enriched yeast, synthetic L-selenomethionine and hydroxy-analogue of selenomethionine. The highest concentrations of MDA, an indicator of secondary lipid oxidation, were confirmed in the Control Group eggs (P < 0.001). Egg yolks from the Control Group were found to have the highest lightness (P = 0.032), the lowest colour chroma and the lowest proportions of the red and yellow colours (P < 0.001). The highest vitelline membrane strength was measured in eggs from groups fed diets supplemented with organic Se (P < 0.001). No significant differences were found between groups in the total fatty acid content, the content of saturated and unsaturated fatty acids or the n-6/n-3 fatty acid ratios. Our study confirmed the effect of Se feed supplements on the concentration of MDA and the colour indicators of egg yolk and on the vitelline membrane strength.