Effects of Dietary Selenium Sources on Performance and Selenium Retention in Broiler Chickens and Laying Hens

摘要

Two experiments were conducted to investigate the effect of dietary selenium sources on performance and selenium retention in broiler chickens and laying hens. In experiment 1, the effects of dietary selenium sources and levels on the weight gain, feed intake, feed conversion, and selenium retention of meat in broiler chickens were investigated. For each growth phase, the basal diet was supplemented with 0 (control), 0.12 and 0.24 ppm Se from sodium selenite (SS) and 0.12, 0.24 and 0.60 ppm Se from selenium yeast(SY). Weight gain was significantly increased(P<0.05) in supplemental 0.24 and 0.60 ppm SY compared to the 0.24 ppm SS by diet during day 1 to 35, but feed intake and feed conversion were not affected by the source or the level of Se. Selenium concentrations of breast and leg muscle were significantly mcreased(P<0.05) in supplemental SS and SY compared to the control, and linearly increased(P<0.05) as dietary. Se level increased by SY, but there was no difference in supplemental 0.12 ppm SScompared to 0.24 ppm SS. In experiment 2, 12-week-experiment using Hy-Line laying hens(31 wk of age) was conducted to compare the effects of selenium sources and levels on egg production, egg weight, daily egg mass, feed intake, feed conversion, egg quality, and selenium retention of egg in laying hens. A corn-soybean meal basal diet was supplemented with 0 (control), 0.06 and 0.12 ppm Se from sodium selenite (SS) and 0.06, 0.12 and 0.30 ppm Se from selenium yeast(SY). Feed conversion was significantlyimproved(P<0.05) in supplemental 0.06 ppm SS compared to the control, but egg production, egg weight, daily egg mass, and feed intake were not affected by source and level of Se. Haugh unit was not affected by source or level of Se. Yolk color was significantly(P<0.05) higher in supplemental 0.3 ppm SY compared to the control and other supplement in week 12. Eggshell breaking strength was significantly(P<0.05) higher in supplemental 0.06 ppm SY(P<0.05). Thickness of eggshell was not affected by sourceor level of Se. Se concentrations of egg was significantly improved(P<0.05) in supplemental SS and SY compared to the control, and was significantly increased(P<0.05) as dietary Se level increased by SS and SY, especially SY more effective compared to the SS.