Abstract
This study was carried out to make early prediction of carcass yield grade. Sixty six Hanwoo steers were measured for back fat thickness, longissimus muscle area and body weight at 18, 21 and 24 months of age by ultrasound. Carcass evaluation was done after ultrasound measurement at 24 month of age. Ultrasonic yield grade at 18, 21 and 24 month of age were predicted by regression and decision tree methods. Classifying by carcass yield grade, ultrasonic back fat thickness at 18, 21 and 24 months of age was significantly different in each carcass yield grade (p<0.05). The prediction accuracy of carcass yield grade by regression method was 78.8% at 18 months, 86.4% at 21 months and 90.9% at 24 months of age. By using the decision tree method for carcass yield grade, 78.8%, 89.4% and 89.4% of prediction accuracy were obtained at 18, 21 and 24 months of age, respectively.
본 시험은 초음파를 이용하여 한우의 도체형질을 조기에 예측하기 위하여 거세한우 66두를 대상으로 18, 21 및 24개월령에 도체형질을 측정하고, 중회귀 분석 및 의사결정나무 분석을 이용하여 24개월령 출하시 도체형질을 예측하였다. 그 결과를 요약하면 다음과 같다. 도체육량등급에 따라 군을 분류하고 성장에 따른 도체형질의 변화를 관찰한 결과, 등지방 두께는 전기간에 걸쳐 각 도체육량등급간에 유의적(p<0.05)인 차이를 보이며 A, B, C등급 순으로 얇게 나타났다. 중회귀 분석에 의한 도체육량등급의 예측율은 18, 21 및 24개월령에서 각각 78.8%, 86.4% 및 90.9%를 나타냈으며, 의사결정나무 분석에 의한 도체육량등급 예측율은 각 개월령에 따라 78.8%, 89.4% 및 89.4%를 나타냈다.
