Estimation of genetic parameters and genetic evaluation of Hanwoo lean meat traits using BLUP

The goal of Hanwoo breeding is to produce large quantities of high-quality beef at a low cost. Breeding research has led to an increase of more than 100 kg in the average carcass weight of Hanwoo cattle. However, carcass weight includes bone and inedible fat, which differ from the percentage of lean meat. Enhancing the percentage of lean meat is essential for improving meat efficiency. Therefore, this study aimed to enhance the productivity of Hanwoo cattle by analyzing 1,905 Hanwoo cattle. This study investigated the correlations between carcass traits (carcass weight, eye muscle area, back fat thickness, and marbling score) and lean meat traits (weight and percentage). Additionally, genetic parameters for lean meat weight and percentage were estimated using the Best Linear Unbiased Prediction (BLUP) method. Based on the estimated genetic parameters, breeding value analysis was conducted. Furthermore, accuracy and correlation analyses between the estimated breeding values and the phenotypic data were performed. The accuracies of the estimated breeding values for carcass traits such as carcass weight, eye muscle area, backfat thickness, and marbling score, were 0.380, 0.373, 0.338, and 0.366, respectively; whereas for lean meat traits, namely weight and percentage, the accuracies were 0.381 and 0.373, respectively. Although the accuracy was relatively low, establishing a larger reference population is expected to enable more precise genetic evaluation. Based on the results of this study, improving lean meat traits is expected to significantly enhance Hanwoo beef productivity.