A study was conducted to determine the dietary effects of Na-bentonite (NaB) and probiotics on meat characteristics and health of Hanwoo steers fed rice straw as a sole roughage source. A total of 24 growing Hanwoo steers (avg BW 232 kg) were assigned to two treatments which included a control diet (concentrate mix and rice straw) and a treatment diet (control diet + 0.5-1.0% NaB + 0.5-1.0% probiotics. The diets were fed for 22 months up to the time the animals were slaughtered. Dietary treatment increased (p<0.05) concentrations of trace minerals such as Zn, Cu, and Fe in the longissimus muscle compared to the control. The treatment diet did not affect cold carcass weight, yield traits such as backfat thickness, longissimus muscle area, yield index, yield grade and quality traits such as marbling score, meat color, fat color, texture, maturity and quality grade. Blood profiles of growing steers were within the normal ranges for healthy cattle. In conclusion, feeding a combination of clay mineral and probiotics to Hanwoo steers fed rice straw as a sole roughage source could have a desirable effect on improving trace mineral retention in longissimus muscle without any deleterious effects on carcass traits of steers.

A study was carried out to evaluate the values of roughages available in Korea on feed intake and digestibility of Korean native goats and consequently to apply its results to the feeding system of Korean goats as a basic information. The results are as f

홀스타인 암소 육성우에 옥수수사일리지와 볏짚을 급여하면서 영양수준을 80, 100 그리고 12%(NRC 요구량 대비)로 급여할때 육성우의 중체량 및 영양소 섭취량을 조사하기 위하여 육성우 30두를 각 처리당 5두씩 완전임의 배치로 공시히여 체중 400kg까지 시험을 수행한 결과는 다음과 같다. 1. 옥수수사일리지 및 볏짚급여시 육성기 최대 일당중체량은 각각 체중 200과 250kg 일때였다. 2. 체중이 증가할수록 DM, CP 및 TDN 요구량은 증가되