Earticle

초록

영어

This study attempted to determine the characteristic features of postpartum dairy cows during their return to estrus. Moreover, it investigated the effects of abnormal ovarian cycles (AOC) on subsequent reproductive performance and the relationship between normal ovarian cycles (NOC) and the blood urea nitrogen (BUN) level postpartum. Incidentally, 56.3% of the Holstein cows and 66.7% of the Jersey cows had NOC, whereas the 43.7% and 33.3% of the Holstein and Jersey, respectively, had AOC. Within 100 days of calving, the cows with AOC had significantly lower rates of artificial insemination (AI) submission as well as pregnancy and a significantly longer interval to first AI, as compared to that in the cows with NOC. Additionally, the cows with NOC had a significantly higher first AI conception rate than that in the cows with AOC. In this study, of the 32 Holstein cows, 8 resumed their ovarian cycle within 20 days of calving, 10 resumed the cycle with 21-40 days of calving, 8 within 41-60 days of calving, while the remaining 6 did not resume their ovarian cycles until 60 days postpartum. Furthermore, the likelihood ratios of incidence of NOC are 0.93, 1.94, and 0.38, respectively, in the groups with BUN levels ＜ 15, 15-19.9, and ≥ 20 mg/ dl. In conclusion, AOC postpartum adversely affects reproductive performance such as AI submission rate, pregnancy rate, interval to first AI and first AI conception rate; moreover, an increase or decrease in the BUN levels beyond 15-19.9 mg/dL leads to the AOC postpartum.

목차

ABSTRACT
INTRODUCTION
MATERIALS AND METHODS
Animal selection
Blood collection and progesterone (P4) analysis
Estrus detection and artificial insemination (AI)
Different types of ovarian cycles and calculation methods of reproductive indices
Statistical analysis
RESULTS and DISCUSSION
CONCLUSION
REFERENCES

키워드

저자

• Doo-San Kim [ Dairy Science Division, National Institute of Animal Science, Department of Animal Life Science, Kangwon National University, Chuncheon 24341, Korea ]
• Ji-Hwan Lee [ Dairy Science Division, National Institute of Animal Science, Cheonan 31000, Korea ]
• Gul-Won Jang [ Dairy Science Division, National Institute of Animal Science, Cheonan 31000, Korea ]
• Eun-Jeong Choi [ Dairy Science Division, National Institute of Animal Science, Cheonan 31000, Korea ]
• Jin-Ju Kim [ Dairy Science Division, National Institute of Animal Science, Cheonan 31000, Korea ]
• Ji-An Lee [ Dairy Science Division, National Institute of Animal Science, Cheonan 31000, Korea ]
• Jun-Kyu Son [ Dairy Science Division, National Institute of Animal Science, Cheonan 31000, Korea ] Corresponding Author

참고문헌

발행기관

간행물

관심저널 등록

• 간행물명

  Journal of Animal Reproduction and Biotechnology

• 간기

  계간

• pISSN

  2671-4639

• eISSN

  2671-4663

• 수록기간

  2019~2025

• 십진분류

  KDC 527 DDC 636