The present study estimated rumen fermentation characteristics and greenhouse gas emissions of different forages. Alfalfa, timothy, tall fescue, Italian ryegrass, and rice straw as the main forage sources for Hanwoo were used in the present study. Crude protein was highest in alfalfa but lowest in rice straw (p<0.05). Ether extract was higher in alfalfa and Italian ryegrass than in the other forages (p<0.05). Crude ash was highest in rice straw but lowest in tall fescue (p<0.05). Neutral detergent fiber was highest in tall fescue but lowest in alfalfa (p<0.05). Acid detergent fiber was highest in Italian ryegrass and rice straw but lowest in alfalfa (p<0.05). In vitro digestibilities of dry matter (DMD) and neutral detergent fiber (NDFD) were highest in timothy but lowest in rice straw (p<0.05). Rumen pH was highest (p<0.05) in alfalfa, while ammonia-N was higher (p<0.05) in alfalfa and Italian ryegrass than in the other forages. Total volatile fatty acid was highest (p<0.05) in timothy, while acetate and propionate were highest (p<0.05) in alfalfa and rice straw, respectively. Acetate to propionate ratio was higher (p<0.05) in alfalfa, timothy, and Italian ryegrass than in rice straw. Rice straw had lowest total gas (mL) (p<0.05) but highest its per DMD and NDFD. Rice straw had higher (p<0.05) CO2 (per DMD and NDFD) compared to alfalfa (per DMD and NDFD), timothy (per DMD and NDFD), tall fescue (per NDFD), and Italian ryegrass (per DMD). Again, rice straw had higher (p<0.05) CH4 (per DMD and NDFD) compared to timothy (per DMD and NDFD) and tall fescue (per NDFD). Therefore, this study indicates that timothy has a higher nutrient digestibility and volatile fatty acid in the rumen leading to a reduction of greenhouse gas emission.

Ⅰ. 서론
Ⅱ. 재료 및 방법
    1. 한우용 조사료
    2. 영양소 함량
    3. In vitro 반추위 내 발효특성
    4. In vitro 반추위 내 가스 발생량
    5. 통계처리
Ⅲ. 결과 및 고찰
    1. 영양소 함량
    2. In vitro 반추위 내 소화율 및 발효특성
    3. In vitro 반추위 내 가스 발생량
Ⅳ. 요약
Ⅴ. 사사

• 주영호(경상국립대학교 농업생명과학연구원) | Young Ho Joo (Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, South Korea)
• 김지윤(경상국립대학교 응용생명과학부(BK21Four)) | Ji Yoon Kim (Division of Applied Life Science (BK21Four), Gyeongsang National University, Jinju 52828, South Korea)
• 서명지(경상국립대학교 응용생명과학부(BK21Four)) | Myeong Ji Seo (Division of Applied Life Science (BK21Four), Gyeongsang National University, Jinju 52828, South Korea)
• 백창현(경상국립대학교 응용생명과학부(BK21Four)) | Chang Hyun Baeg (Division of Applied Life Science (BK21Four), Gyeongsang National University, Jinju 52828, South Korea)
• 정승민(국립축산과학원 초지사료과) | Seung Min Jeong (Grassland and Forages Division, National Institute of Animal Science, RDA, Cheonan 31000, South Korea)
• 김삼철(경상국립대학교 농업생명과학연구원, 경상국립대학교 응용생명과학부(BK21Four)) | Sam Churl Kim (Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, South Korea, Division of Applied Life Science (BK21Four), Gyeongsang National University, Jinju 52828, South Korea) Corresponding author