• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.183-190
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• 2003

Data from live animal real time ultrasound (RTU) measures from 127 Hanwoo steers were used to assess nutritional physiology and relationship between RTU measures and real carcass measures represented meat quality. Traits considered were longissimus muscle area, fat thickness, and marbling score imaged and scanned using RTU by month and those of carcass measures at about 24 month of age. On this study, increasing pattern for longissimus muscle area would be closely related to growth pattern (p<0.01) and it of fat thickness would be related to quadratic effect of ages. Marbling score would be related to aging, that is, individual deviates of scores were distinctly characterized after 17 mo. even though they were started at about 11 mo. Correlation estimates between RTU measures and corresponding carcass traits were over 0.6 after 17 month of age for all traits considered and these estimates were high as 0.90 after 22 month of age. From this study, Real-time ultrasound measurement would be valuable after 15-17 mo. and measures at about 22 mo. would be helpful to decide age for slaughtering. To utilize these techniques for beef cattle breeding via progeny testing program, 15 mo. RTU measures would be efficiency rather than 12 mo. of other beef breeds. Further study to find genetic variation of RTU measures was needed to utilize these technologies for beef breeding.

• Korean Journal of Poultry Science
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• v.12 no.2
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• pp.53-57
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• 1985

This study was carried out to estimate genetic correlations among broiler body weights for the selection of broiler breeders at early age, and to investigate the difference of growth rates between male and female in mixed-sex population of broiler from 2wks to 8 wks of age. A total of 1109 records were used in this study. the heritability estimates from combined variance components for 2-,4-, 6- and 8- weeks body weights were 0.32, 0.31, 0.35 and 0.29 respectively. Genetic correlations were 0.91 between 4wks and 8wks body weights, 0.94 between 6wks and 8wks body weights. Records obtained on 4wks and 8wks might be useful in a selection program to improve traits in 8wks broiler weight. Growth rates of male and female from nonlinear equations from 2wks to 8wks were shown differently in both linear and quadratic terms, Even though both sexes showed closely equal body weights at 2wks of age, they manifested great difference about 300g at 8wks of age. At all. ages roles were havier, grew at a faster than female. From this result it might be profitable either to select the combination of lines which has little sex effect or to rear male and female broiler separately up to the marketing body weights.