Diets different in crude protein (CP) and undegraded intake protein (UIP) contents were offered to sheep in a metabolism study to describe their effects on nutrient digestibility and nitrogen (N) metabolism. Six Corriedale sheep (body weight=56.2±2.3 kg) were divided in random within a Latin square design (replicated) to 1 of 3 diets: 1) a low-CP diet (LP; 12.2% CP with 35.1% UIP), 2) high CP with low UIP diet (HPLU; 14.9% CP with 33.7% UIP), and 3) high CP with high UIP diet (HPHU; 15.5% CP with 45.8% UIP). High-protein dried distillers grain and soybean meal were the main CP sources for the adjustment of UIP:DIP in the diets. No significant differences were found in feed consumption and nutrient digestibility; however, a greater proportion of CP was digested in sheep fed the HPLU diet (69.4%; P=0.04). Although N intake was greater in sheep receiving HPLU and HPHU diets, loss of N through fecal or urinary route was not different among sheep, which resulted in the highest (12.7 g/d) and lowest N retention (7.40 g/d) in HPHU- and LP-fed sheep, respectively. In conclusion, although CP or UIP content had marginal effects on feed consumption and whole-tract digestibility of the majority of nutrients, with the increased CP and UIP levels in the diet, the efficiency of N utilization was improved with regard to increased N retention with minimal differences in N excretion, which is important from an economic and environmental standpoint.

This study evaluated the effects of TMC (trace mineral-fortified microbial culture) supplementation on growth performance, carcass characteristics, and meat quality parameters of Hanwoo steers during the last 4 months of finishing period. The TMC was a combination of 0.4% trace minerals, 20.0% Na-bentonite, and 79.6% feedstuffs, which was inoculated with a mixed microbial culture (Enterobacter ludwigii, Bacillus cereus, B. subtilis, Lactobacillus plantarum, and Saccharomyces cerevisiae). Twenty-four steers were blocked by initial BW (634 ± 16 kg) and randomly allocated to one of two treatments (control vs. 3.3% TMC). The effect of TMC supplementation on the growth performance was not significant. There was no incidence of urolithiasis in TMCfed steers. However 3 out 12 steers (25%) fed the control diet were observed to have urinary calculi. The carcass yield and meat quality parameters were not affected by TMC supplementation, however marbling score was increased in TMC-fed steers (P = 0.08). There was no effect of TMC treatment on the chemical composition of longissimus dorsi muscle (LM). The TMC supplementation increased concentrations of manganese (P < 0.01), cobalt (P = 0.02), iron, and copper (P = 0.06) in LM. In conclusion, TMC treatment did not negatively affect growth performance and meat quality parameters, and positively affected the trace minerals profile of LM.

본 연구는 버섯재배부산물, 재활용가금깔개, 미강 및 straw로 구성되는 BF 사일리지 급여가 육성 거세한우의 행 동양상에 미치는 영향을 규명하기 위하여 실시하였다. 시 험에 사용한 공시 한우는 11개월령 총 10두(평균 301.7 kg) 를 2처리로 배치하였으며, 이 때 대조구(볏짚 자유채식)와 처리구(BF silage 자유채식)로 하여 48시간 행동관찰을 실 시하였다. 대조구와 비교해서 BF 사일리지 급여구는 총 DM 섭취량과 NDF 섭취량이 각각 30% 및 36% 높았고, 채식시간, 반추시간 및 저작시간은 유의적인 차이가 없었 다. 식괴수, 식괴당 반추시간에 있어서도 유의적 차이가 없 었고, 식괴당 저작수와 FVI는 낮게 나타났다(p<0.05). 또한 대조구와 비교해서 BF 사일리지 급여구는 배뇨 회수가 높 고(p<0.05), 음수 및 배분 회수에 있어서는 상호간에 차이 가 없었고, 채식율, 반추효율 및 저작효율에 있어서는 더 높게 나타났다(p<0.05). 이상의 결과로 볼 때, BF 사일리지 급여는 볏짚과 비교 시 육성거세한우의 반추행동 상 큰 차 이가 없다는 결과로 미루어 볼 때 차후 볏짚 대용으로 활 용하여도 좋을 것으로 사료되었다. 즉 입자도가 큰 straw를 peNDF를 충족시키는 최소량을 혼합하여 부산물사료 사일 리지를 제조, 급여하였을 때 육성거세한우의 반추행동은 볏짚 급여 시와 차이가 없었다.