This study was conducted to investigate the effect of feeding with dietary silicate based complex mineral (SCM) on the performance of laying hens. SCM at five levels (0%, 0.2%, 0.4%, 0.6% and 0.8%) was added to commercial diets, and fed to four hundred fifty Hy-Line Brown from fifty four to sixty five weeks of age. Egg production increased as the addition of dietary SCM to basal diets increased up to 0.6% (P<0.05). Furthermore, Feed intake increased in a manner similar to that of egg production (P<0.05). However, there was no difference in feed efficiency among the treatments. Eggshell thickness and breaking strength were significantly higher for the chickens fed with SCM than control from sixty weeks old to the end of experiment (P<0.05). Similarly, albumen height and Haugh unit were significantly higher for the chickens fed with SCM compared to those of control group (P<0.05). AST of birds fed SCM showed significantly higher than control (P<0.05). However, blood neutral fat level tended to increase in SCM treatments. Moreover, bone mineral density increased with SCM addition up to 0.4% (P<0.05). IL-2 (Interleukin-2) and IL-6 (Interleukin-6) levels appeared to be improved in the chickens fed with SCM addition diets, although not statistically different from all treatments. The results of this study indicated that the optimum SCM for improving the performance, egg quality and immunological competence of laying hens from 54 to 65 weeks of age was 0.6%.(Key words: egg quality, immunological competence, laying hens, performance, silicate complex mineral) โ To whom correspondence should be addressed : seon@jbnu.ac.kr ์ ๋ก ๊ตญ๋ด์์ ์ฃผ์ ๊ด๋ฌผ์ง์ ์ํ๋ ๊ท์ฐ์ผ๊ณ ๋ณตํฉ๊ด๋ฌผ์ง์ ๋๋ฆฌ ๋ถํฌ๋์ด ์์ผ๋ฉฐ, ํ๋ฉด์ ์น์์ฑ ๋ฏธ์ธ๊ตฌ๋ฉ์ด ๋ค๋ ์กด์ฌ ํ์ฌ ํก์ฐฉ๋ ฅ์ด ๊ฐํ๋ฏ๋ก ์ฐ์
์ ์ผ๋ก ํ ์ง๊ฐ๋๊ณผ ์ด์จ๊ตํ ์ฅ์น ๋ฑ์ผ๋ก ๊ด๋ฒ์ํ๊ฒ ์ด์ฉ๋์ด ์์ผ๋ฉฐ, ์ถ์ฐ์
์์๋ ์ด ๋ฌํ ๊ท์ฐ์ผ ๊ณํต ์ด์ธ์๋ ์ ์ค๋ผ์ดํธ(zeolite), ๋ฒคํ ๋์ดํธ (bentonite), ๊ณ ๋ นํ (kaolin) ๋ฐ ํ์ด๋ชจ(biotite) ๋ฑ์ ํ์ฉํ์ฌ ํญ์์ ๋ฅผ ๋์ฒดํ๋ ์ฌ๋ฃ์ฒจ๊ฐ์ ๋ก ์ฐ๊ตฌํ์ฌ ์๋ค (Safaeikatouli et al., 2011;Melegy et al., 2015;Yenice et al., 2015).