The Optimal TDN Levels of Concentrates and Slaughter Age in Hanwoo Steers

거세한우에 있어서 배합사료의 적정 TDN 수준과 도축 월령

  • Kim, K.H. (National Livestock Research Institute, RDA) ;
  • Lee, J.H. (Department of Animal Science, GyeongSang University) ;
  • Oh, Y.G. (National Livestock Research Institute, RDA) ;
  • Kang, S.W. (National Livestock Research Institute, RDA) ;
  • Lee, S.C. (Ministry of Agriculture and Forestry) ;
  • Park, W.Y. (Samyang Corporation) ;
  • Ko, Y.D. (Department of Animal Science, GyeongSang University)
  • Published : 2005.10.31


Ninety Hanwoo steers(initial BW=167.2$\pm$13.4kg) were used to determine the effect of energy concentrations in concentrates and slaughter age on performance, carcass characteristics. Steers were allotted by BW to one of eighteen pens. Eighteen pens were randomly allotted to a low(70-70-71-72% for the growing, the early, the middle or the late fattening periods), medium(70-71-72-73%) or high(70-72- 73-74%) TDN level of concentrates. Five steers for each treatment of energy level were slaughtered every one month from 26 month of age to 31 month of age. Concentrates was fed restrictedly to achieve a predicted gain of 0.7-0.9kg from growing stage to middle fattening stage. All steers were fed orchard grass(Dactylis glomerata L.) hay as roughage during the growing period, fed rice straw gradually substituted for orchard grass hay during the early fattening period, and fed rice straw only thereafter. Overall body weight and feed intake were not affected by TDN levels of concentrates. Average daily gain for all treatments was higher than 0.9kg/d during the 19-21 month of age and decrease thereafter, but sustained above 0.7kg/d. Mean concentrates intake for all treatments was 1.0-1.3% of live BW during the growing period and 1.5% during the early fattening. Thereafter, it decreased up to 1.4% during the middle fattening and 1.0% during late fattening period. Delay of slaughter end point resulted in a gradual increase of rib-eye area, back fat thickness and marbling score, especially after slaughter age of 29 month there was significant increases(P<0.05). The appearance rate of 1+ and 1 grade related to the slaughter ages was 100% at 29, 30 and 31 months of age, whereas those at 26, 27 and 28 months were 93, 86 and 80%, respectively. Dressing rate was significantly(P<0.05) increased and rate of retailed cut weight significantly(P<0.05) decreased when slaughter age increased. In economic analysis, there was pronounced increase in net income up to 32-46% after slaughter age of 29 months. Under the conditions of this study, high TDN intake is not necessarily required for high quality Hanwoo meat production and slaughter age of 29 month might be the optimum for Hanwoo steers.


  1. 山崎敏雄. 1988. 黑毛和種去勢牛の體組織の發育に關する硏究. 日本草地試驗場. p. 11
  2. 강수원, 김준식, 조원모, 안병석, 기광석, 손용석, 2002. 육성비육 거세한우에 대한 점토광물 급여가 성장 및 도체특성에 미치는 영향. 한국동물자원과학회지 44(3):327
  3. 김내수, 주종철, 송만강, 정정수, 최양일, 박철진. 2002. 한우 거세 및 비거세우의 성장곡선 특성. 한국동물자원과학회지. 44(5):519
  4. 농림부, 축산기술연구소. 1998. 한우 고급육 생산기술개발 보고서
  5. 농촌진흥청. 2003. 농업경영 개선을 위한 2002 농축산물 소득 자료집
  6. 백봉현, 신기준, 김용곤, 이근상, 김강식. 1987. 한우육성비육시 체중별 육생산과 사료효율 및 적정출하체중에 관한 연구. 농시논문집. 29(1):6
  7. 송만강, 김내수, 정정수, 최양일, 원유석, 정재경, 최성호. 2000. 농후사료 급여수준이 거세 한우의 증체와 부위별 지방조직의 지방산에 미치는 효과. 한국동물자원과학회지 42(6):859
  8. 이주환. 2005. 거세한우의 에너지 수준과 비육기간이 육질과 육량에 미치는 영향. 경상대학교 석사학위논문
  9. 홍성구, 백봉현, 강희설, 조원모. 1996. 거세한우에 대한 제한급여 수준과 출하체중이 비육능력 및 육질에 미치는 효과. 한국축산학회지 38(3): 215
  10. 축산물등급판정소. 2003a. 축산물등급판정세부기준 농림부 고시 제 003-14호
  11. 축산물등급판정소. 2003b. 축산물등급판정연보

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