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

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 increased(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 SS compared 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 significantly improved(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 source or 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.

Selenium의 첨가가 육계 및 산란계의 생산성 및 축적에 미치는 효과

셀레늄의 첨가가 육계 및 산란계의 생산성과 축적에 미치는 영향을 구명하기 위하여 2차례의 실험을 수행하였다. 실험 1은 무기태 selenium 0.12, 0.24 ppm과 유기태 selenium 0.12, 0.24 및 0.6 ppm의 첨가가 육계의 사료 섭취량, 증체량, 사료 요구율 및 닭고기 내 selenium 축적에 미치는 영향을 조사하였다. 시험 전 기간의 증체량은 무기태 0.24 ppm 첨가구보다 유기태 selenium 0.24와 0.60 ppm 첨가구에서 높았다(P<0.05). 그러나 사료 섭취량과 사료 요구율은 대조구, 무기태 및 유기태 selenium의 첨가 수준에 의한 차이는 없었다. 가슴과 다리근육의 selenium 함량은 대조구에 비하여 유기태와 무기태 selenium 첨가구가 높았으며(P<0.05), 유기태 selenium의 첨가 수준에 따른 차이는 있으나(P<0.05), 무기태 selenium의 첨가 수준에 따른 차이는 없었다. 실험 2에서는 산란계 사료에 무기태 selenium 0.06, 0.12 ppm과 유기태 selenium 0.06, 0.12 및 0.30 ppm의 첨가하여 급여시에 산란율, 사료 섭취량, 사료 요구율, 난질 및 계란 내 selenium 함량에 미치는 영향을 조사하였다. 사료 요구율은 무기태 0.06 ppm 첨가구가 대조구보다 유의적으로 개선되었으나(P<0.05), 산란율, 난중, 1일 산란량, 사료 섭취량은 대조구, 무기태 및 유기태 selenium의 첨가 수준에 따른 차이는 없었다. Haugh unit는 모든 처리구에서 차이가 없었으며, 난황색은 유기태 selenium 0.30 ppm 첨가구가 대조구를 포함한 다른 처리구에 비하여 높았다(P<0.05). 난각 강도는 유기태 selenium 0.06 ppm 첨가구가 높았다.(P<0.05). 그러나 난각 두께는 대조구를 포함한 모든 처리구에서 차이는 없었다. 계란 중의 selenium 함량은 대조구에 비하여 selenium을 첨가한 모든 처리구에서 높았다(P<0.05). 이외에도 사료내 selenium 첨가 수준에 비례하여 계란에서 selenium 축적량도 증가하였으며(P<0.05), 특히 유기태 selenium 이 무기태 selenium보다 효과적이었다.