These studies were conducted to evaluate developmental competence of follicular oocyte collected from the ovaries of Hanwoo cows with the high offspring meat quality (1++ and 1+ grade). Cumulus oocyte complexes from individual cows were matured, fertilized and cultured using protocols of in-vitro maturation (IVM), in-vitro fertilization (IVF) and in-vitro culture (IVC). The rates of blastocyst development from Hanwoo cows with the offspring meat quality grades of 1++ and 1+ were 18.6 and 21.2%, respectively. The rates of blastocyst development were 26.3, 20.7, 20.7, 17.2 and 31.2% from Hanwoo cows with the meat quality grades of 1++, 1+, 1, 2 and 3, respectively. Fiftyseven transferable embryos were recovered from 11 Hanwoo donor cows (5.2/head) with the high offspring meat quality grades of 1++ and 1+ in vivo, and the pregnancy rate after embryo transfer was 61.1%. In conclusion, these results suggest that in vitro embryo production from the ovaries of cows with the high meat quality grades using individual culture system can be used an efficient method for livestock improvement. In addition, for the successful industrialization of embryo transfer, conception rate should be improved.

ABSTRACT
 서 론
 재료 및 방법
  체외수정란 생산
  체내수정란 생산
  통계분석
 결 과
  도축 한우 암소의 등록 현황
  도축 한우 암소의 후대와 당대의 육질등급에 따른 체외수정 및배반포 발달
  체내수정란 회수 및 수정란이식 후 수태율
 고 찰
 결 론
 CONFLICTS OF INTEREST
 REFERENCES

• 이해이(전라북도동물위생시험소 축산시험장) | Hae-Lee Lee (Livestock Experiment Station, Jeollabuk-do Institute of Livestock and Veterinary Research)
• 박재희(전북대학교 동물자원과학과) | Jae-Hee Park (Department of Animal Sciences, College of Agriculture & Life Science, Chonbuk National University)
• 김용수(전라북도동물위생시험소 축산시험장) | Yong-Su Kim (Livestock Experiment Station, Jeollabuk-do Institute of Livestock and Veterinary Research)
• 김종국(전북대학교 동물자원과학과) | Jong-Gug Kim (Department of Animal Sciences, College of Agriculture & Life Science, Chonbuk National University) Correspondence