韓牛의 體重과 體型에 對한 遺傳力, 遺傳相關 및 早期選拔에 關한 硏究 = Study on the Heritabilities, Genetic Correlations and Early Selection on Body Weight and Body Measurements of Korean Native Cattle

다국어 초록 (Multilingual Abstract)

The purpose of this study was to establish the genetic basis for the improvement of Korean Native Cattle.
The data used in this study were the records of 407 Korean Native Cattle which were raised at the Livestock Experiment Station and Alpine Experiment Station for 11 years from 1960 to 1970. Heritabilities were estimated by the method of variance component analysis(paternal half-sib method) for 55 economic traits. Phenotypic, genetic and environmental correlations among these traits were also estimated, and selection indexes were constructed to investigate the methods of early selection for effective improvement of these economic traits. The results obtained are as follows;
1. The heritabilities estimated were 0.220 for body weight at birth, 0.039 at 3 months, 0.208 at 6 months(weaning), 0.144 at 9 months, 0.178 at 12 months, 0.252 at 15 months, 0.516 at 18 months, 0.435 to 0.909 for withers heights, 0.443 to 0.586 for hip heights, 0.330 to 0.529 for body lengths, 0.219 to 0.767 for chest girths, 0.142 to 0.853 for rump lengths, 0.025 to 0.348 for hip widths, 0.422 to 0.553 for pine widths and 0.087 to 0.411 for shank circumferences, respectively.
2. The genetic correlations were -0.815 to 0.089 among body weights, 0.489 to 0.995 among withers heights, 0.391 to 0.991 among hip heights, 0.344 to 0.977 among body lengths, 0.148 to 0.985 among chest girths, 0.068 to 0.936 among rump lengths, -0.001 to 0.957 among hip widths, 0.652 to 0.980 among pine widths and -0.551 to 0.999 among shank circumferences, at different ages, respectively. Correlations of body weights with withers heights, hip heights, body 0.542, -0.052 to 0.644, 0.354 to 0.603 and -0.717 to 0.859, respectively. The genetic correlations between body measurements at different ages were from -0.385 to 1.047.
On the basis of the results obtained in this study, it is recommended that for the improvement of growth rate, selection should be practiced for body weight and body measurements at 12 months, and for postweaning gain after 6 months of age.