The Effect of Various Forms and Doses of Selenium Supplementation of the Hens Diet on Selected Qualitative Parameters and Freshness of Table Eggs

In this experiment the effects of supplementing of the diet for laying hens with sodium selenite (SS) or selenized yeast (SY) on the quality and content of some minerals of eggs were studied. Hy-Line Brown chickens were randomly divided on the day of hatching into 4 groups (12 birds per group). The birds were fed from day 1 of life till 9 months of age with diets differing in amounts and/or forms of selenium. The control group received a basal diet (BD) containing selenium naturally occurring in feeds (0.1 mg Se/kg of dry matter (DM)). The first and second experimental groups were fed by the same BD enriched with Se at a dose of 0.4 mg/kg DM from sodium selenite or selenized yeast, respectively. The feed for the third experimental group consisted of BD supplemented with selenized yeast to a final selenium content of 1.0 mg/kg DM. The results showed that supplementation of SY to the diet significantly affected egg weight and Haugh units. The Haugh units in both hybrids were higher in all experimental groups of hens fed with feed supplement of selenium in both forms, with significant differences only in the groups with addition of organic forms at both doses compared to the control group (84.52±3.87, 86.60±3.80, 87.21±4.10*, 86.93±3.56*, P<0.05), respectively. Freshness of eggs was positively influenced by the addition of selenium, but with no statistically significant difference (P>0.05). Higher values were recorded in each of the four analyzes in the groups with the addition of selenium in the form of selenized yeast. Analyzing after three weeks of storage showed an obvious decrease of Haugh units in relation to the decreasing quality of the internal contents of eggs (75.39±3.07, 76.15±2.97, 78.77±4.32, 78.24± 4.84, P>0.05) but still retained a tendency to higher values in groups with the addition of selenium, especially organic form.