This study was conducted to investigate the possibility of replacing imported Timothy hay (TH) with domestic Italian ryegrass silage (IRGS) as a horse feed considering feed quality, nutrient digestibility and feed price. Two experimental diets (TH and IRGS) were fed to six-headed Thoroughbred (body weight, 475.7±33.3kg) of the Korea Racing Authority of Wondang Stud Farm. The 3 head animals were assigned to Control group (TH) and Treatment group (IRGS), respectively. The nutrient digestibility was determined by the total collection method. IRGS is enough for using as a horse feed because its Relative feed value(RFV) was higher than TH and its fermentation quality is suitable for horses. Although no difference was observed in nutrient digestibility, Total digestible nutrients(TDN), and Digestible energy(DE) between Control and Treatment group (p>0.05), the fact that price of IRGS was much lower (53.7~62.4%) than that of TH indicates IRGS has competitive advantage over TH as a horse forage feed. The present study indicates that IRGS can be fully replaced with TH due to its superior economic value even though the similarity of its nutrient digestibility, TDN, and DE to TH.

ABSTRACT
Ⅰ. 서 론
Ⅱ. 재료 및 방법
    1. 공시시료 및 처리
    2. 공시동물
    3. 소화실험
    4. 조사항목 및 조사방법
    5. 통계분석
Ⅲ. 결 과
Ⅳ. 고 찰
Ⅴ. 요 약
Ⅵ. 사 사
Ⅶ. REFERENCES

• 김지융(강원대학교 동물생명과학대학) | Ji Yung Kim (College of Animal Life Sciences, Kangwon National University)
• 손진(한국식품안전관리인증원) | Jin Son (Korea Agency of HACCP Accreditation and Services)
• 이배훈(농촌진흥청 국립축산과학원) | Bae Hun Lee (National Institute of Animal Science, RDA)
• 김병완(강원대학교, 동물생명과학대학) | Byong Wan Kim (College of Animal Life Sciences, Kangwon National University)
• 성경일(강원대학교, 동물생명과학대학) | Kyung Il Sung (College of Animal Life Sciences, Kangwon National University) Corresponding author