Earticle

초록

영어

The objective of this study was to identify the phenotypic relationships among calving difficulty, calf birth weight and gestation length of Holstein dairy cattle under the environment of Korea. A total of 1,834 calving records collected by Dairy Science Division of National Institute of Animal Science, RDA from 2000 to 2014 was analyzed. General linear multivariate models for calving difficulty scores (CD: 1=no assistance, 2=minor assistance, 3=two to three persons assisted, 4=more than three persons assisted, 5=cesarean section), calf body weight at birth (BW), and gestation length (GL) included fixed effects of year and season (spring, summer, autumn, winter) of births (YS), sex of calves, and parity. For GL and BW, all three fixed effects (YS, sex of calves, parity) were significant (p<0.05). For CD, the effects of YS and sex of calves were significant (p<0.05). Bull calves were born with heavier BW by 3.18 kg, with greater CD by 0.18 point and with longer GL by 0.6 days than heifer calves. The least squares mean of BW was the heaviest at the third parity (44.1 kg) compared to those at the first, the second and the fourth parities or later (41.3-41.9 kg). The least squares mean CD at the first parity was 1.74 point, which was higher than CD at the second and later parities (about 1.68 points). Phenotypic correlation (partial residual correlation) between GL and BW was 0.36. But those between GL and CD and between BW and CD were -0.03 and 0.04, almost zeros. To conclude, we observed higher incidence of calving difficulty in the first calving than in the later ones. Further investigation on the relationships between calf’s birth weight and calving difficulty is needed.

목차

ABSTRACT
 Ⅰ. 서론
 Ⅱ. 재료 및 방법
 Ⅲ. 결과
 Ⅳ. 고찰
 Ⅴ. 요약
 사사
 Ⅵ. REFERENCES

저자

• 최연호 [ Yun Ho Choy | 농촌진흥청 국립축산과학원 ] Corresponding author
• 원정일 [ Jeong Il Won | 농촌진흥청 국립축산과학원 ]
• 윤호백 [ Ho Baek Yoon | 농촌진흥청 국립축산과학원 ]
• 조광현 [ Kwang Hyun Cho | 농촌진흥청 국립축산과학원 ]
• Alam Mahboob [ 농촌진흥청 국립축산과학원 ]
• 조충일 [ ChungIl Cho | 농촌진흥청 국립축산과학원 ]
• 연성흠 [ Seong Heum Yeon | 농촌진흥청 국립축산과학원 ]
• 박병호 [ Byoungho Park | 농촌진흥청 국립축산과학원 ]
• 양보석 [ Bohsuk Yang | 농촌진흥청 국립축산과학원 ]

참고문헌