Metabolic Profiles and Their Correlation with Carcass Traits in Japanese Black Steers under Progeny Testing

Abstract

The objective of this study was to investigate the improvement of production efficiency in Japanese Black cattle by determining its metabolic profiles during a shortened fattening period and by revealing the correlations among the profiles and carcass traits. Data were collected from 172 Japanese Black steers that were part of the progeny testing scheme at the Livestock Improvement Association of Miyazaki. A significant increase was observed in the α-tocopherol, glutamic oxaloacetic transaminase, total cholesterol and blood urea nitrogen levels, from 8 to 18 months of age, the finishing period. On the other hand, at 18 months of age, creatine phosphokinase showed a significant negative correlation with rib thickness and negative correlations with other carcass traits except for beef marbling score, although not significant. The least square mean of the sire candidates for creatinine activity at 11 months of age had a positive correlation with longissimus muscle area and carcass yield estimate. In our study, metabolic profiles of the Japanese Black steers during the short fattening period, which has not been reported so far, have been determined. Our results suggest that there is a genetic association between plasma α-tocopherol or creatinine levels and the increase in muscle or meat.