Effect of selenium on performance, egg quality, egg selenium content and serum antioxidant capacity in laying hens

Abstract

The objective of this work was to compare the effect of sodium selenite (SS) and selenium yeast (SY) on performance, egg quality, selenium concentration in eggs and serum antioxidant capacity in laying hens. Seven-hundred and twenty 21-week-old healthy Roman laying hens with a similar laying rate were randomly divided into 5 groups with 6 replicates of 24 hens. The experiment was designed by 2 × 2 factorial arrangement with two sources of Se and two levels of Se. The hens in control group were fed a basal diet without adding exogenous selenium source, and the hens in other four groups were fed basal diets supplemented with SY and SS containing 0.3 ppm and 0.5 ppm, respectively. Pre-trial period lasted 7 d and experimental period lasted 42 d. The results showed that: compared with the control diets, 1) there was significant difference in average daily feed intake, and feed conversion rate (P < 0.05), but no difference in egg quality and laying rate (P > 0.05); 2) there was significant difference in serum GSH-Px and MDA (P < 0.05). No difference in SOD, CAT and T-AOC (P >0.05). Compared with basal diets, adding selenium lead to increase serum GSH-Px and decrease MDA; 3) there was significant difference on egg selenium content after feeding different sources and levels of Se (P < 0.05). Compared with basal diets, adding 0.3 or 0.5 ppm SY can improve egg selenium content 89.5%, 139.2% respectively; adding 0.3 or 0.5 ppm SS in diets can improve egg selenium content 78.3%, 93.2% respectively. In conclusions, adding selenium increase laying hen antioxidant capability and egg selenium contents. We suggested that adding 0.5ppm SY in the diet of laying hens to produce Se-rich egg.