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KMID : 1025520090510020105
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Journal of Animal Science and Technology
2009 Volume.51 No. 2 p.105 ~ p.110
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Comparison of Proven and Young Holstein Bulls for Major Economic Traits
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Choi You-Lim
Cho Kwang-Hyun
Jeon Byeong-Soon
Baek Kwang-Soo
Park Byoung-Ho
Lim Hyun-Joo
Kim Hyo-Sun
Cho Joo-Hyun
Ahn Byeong-Seog
Kim Nae-Soo
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Abstract
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The Objective of this study was to compare performances of proven and young holstein bulls bred in Korea. Proven bulls are categorized into the imported and the korean ones. Data from 148,329 heads of daughters of 1,128 bulls from 1990 to 2004 were used in this study. Proven bulls showed higher milk yield than young bulls in same year. Young bulls, however, always yielded more milk than korean bulls when proven bulls were categorized into the imported and the korean ones. Hence, it was proven that dairy bull selection program had properly been functioned in Korea. Selected bulls, which were korean proven bulls and young bulls, yielded higher milk fat than imported bulls as the selection was weighted on the yield of the milk fat. This comparison was based on the performances of daughters without the consideration of the semen price. Semen price of the imported proven bulls were higher than the korean proven bulls and the semen of young bulls was free. Hence, the performances of korean bulls with the consideration of the preferential effect would be much higher than others, and further studies are necessary.
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KEYWORD
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Holstein, Proven bull, Young bull, Progeny test
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