Effects of carcass traits, proportion of monounsaturated fatty acids and fineness index of marbling on the carcass unit price of Japanese Black cattle in Hyogo prefecture

Abstract

Using 6,564 Japanese Black cattle slaughtered at a meat market in Hyogo prefecture, we conducted the least squares analysis of variance by assigning the carcass unit price as a dependent variable. The analytical model included carcass traits, proportion of monounsaturated fatty acids (MUFA) estimated by fiber-optic near-infrared spectrometer, and fineness index of marbling obtained by digital image analysis. All the explanatory variables, except for subcutaneous fat thickness and beef fat score, had significant effects on the carcass unit price (P < 0.05). We verified that MUFA and fineness index showed significant effects on the carcass unit price, whereas beef marbling score (BMS) had large impact on it. When the same analysis was applied to each of the four subsets of the data, generated by subdividing all the data by BMS, it was found that fineness index and MUFA significantly affected the carcasses unit price in high (10 ≤) and moderate (6 to 9) BMS categories, respectively. Partial regression coefficients of the both traits were positive in all the subsets of the data, indicating that improvements of these two traits might increase the economic values of the carcasses.