| Summary: | 碩士 === 國立宜蘭大學 === 生物技術與動物科學系 === 104 === Addition of inorganic selenium (Se) in Schizophyllum commune solid fermentation can convert Se to the organic form and produce large molecular polysaccharide in the enriched Se S. commune culture (Se-SCC) but its’ effect as feed additive is not yet clear. This trial was therefore conducted to evaluate effects of the different levels of Se content Se-SCC inclusion in layer feed on production performance and egg selenium concentration in laying hens. A total of 400 28-week-old laying hens were randomly allocated into sixteen pens with four dietary treatments: control diet, control diet supplemented with inorganic Se (0.15 mg/kg Se from Na2SeO3, SS), control diet supplemented with 0.2% low level Se-SCC (0.15 mg/kg Se from Se-SCC, LSCC), and control diet supplemented with 0.2% high level Se-SCC (0.60 mg/kg Se from Se-SCC, HSCC). Hens were housed in 4 m2 floor pens with set nests for 8 weeks. Production performance was measured weekly, and 2 eggs per pen were randomly collected every 4 weeks for analysis of egg quality and egg Se concentration. Two birds per pen were randomly selected and the blood samples taken at the end of the trial to assay serum antioxidant responses. Results showed the egg weights were increased and the feed/egg ratios went down as the trial progressed. Dietary supplementation of LSCC and HSCC significantly increased the ADFI than the other 2 groups (P < 0.05), and LSCC tended (P = 0.10) to enhance the egg weight than that of SS groups during whole trial period. However, dietary treatment showed little effect on egg production, egg mass, feed/egg ratio, or egg quality in the fresh stage. Supplementation of Se enhanced the serum trolox equivalent antioxidant capacity (TEAC) and glutathione peroxidase activity (GPx). Moreover, the HSCC was the highest among the groups which tended to reduce the egg malondialdehyde (MDA) level after 10 days storage in room temperature of the second period. Dietary supplementation of Se linearly increased egg Se concentration (y = -0.0623 ＋ 1.3229x － 0.8999x2, R² = 0.76), but linearly reduced the egg Se deposition efficiency (y = 44.57 － 25.69x, R² = 0.49). However, the LSCC was still 4.2% better in the Se deposition efficiency than that SS under the same dietary Se level (36.96 vs. 35.48%, P > 0.05). In conclusion, dietary supplementation of high dose of Se enriched S. commune culture was proven to improve egg antioxidant and egg Se, however, the Se deposition efficiency was similar as the inorganic Se under supplementation 0.15 mg/kg Se from LSCC.
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