PSV-23 Prediction of retail yield for purebred and crossbred Jersey cattle raised for natural markets

Abstract

Abstract The USDA yield grade (YG) equation is used to predict the cutability of beef carcasses for the more accurate payment of cattle when sold in grid pricing systems. In the United States, an increasing percent of Jersey genetics are being implemented into dairy farms, which is resulting in a greater percent of Jersey genetics contributing to the fed beef cattle supply. Cattle (n = 91) were fed a similar diet, harvested, and fabricated into boneless closely trimmed retail cuts (BCTRC). Inconsistencies occurred between the calculated USDA YG and %BCTRC compared to actual measures from purebred and crossbred Jersey cattle. Therefore, the objective was to evaluate the validity of the current USDA YG equation to predict the cutability of purebred and crossbred Jersey cattle raised for natural markets. Data were analyzed in SAS with the mixed model: Yijklm = μ + (EQ×HCW)ij + (EQ×BFT)ik + (EQ×LMA)il + (EQ×KPH)im + eijklm, where EQi = the USDA predicted estimates or actual Jersey measurements. Jersey YG [Y=9.66+(0.005×HCW)+(0.54×BFT)+(-0.035×LMA)+(0.083×KPH)] and %BCTRC [Y=34.68+(-0.012×HCW)+(-1.01×BFT)+(0.081×LMA)+(-0.192×KPH)] equations more accurately predicted the retail yield of the purebred and crossbred Jersey cattle in the present study compared to the current USDA equations. The parameter estimates for the y-intercept (P ≤ 0.01), BFT (P ≤ 0.01), and LMA (P = 0.06) were different between the current USDA YG and the Jersey YG equations and current %BCTRC and the Jersey %BCTRC equations. Mean differences between the calculated and actual YG and % BCTRC were 5.8 USDA YG and 13.1% BCTRC. In conclusion, the current USDA YG equation over predicted the retail yield of purebred and crossbred Jersey cattle in the current study. Evidence of such disparities between calculated and actual values may warrant a reevaluation for the use of the USDA YG for the prediction of beef carcass retail yield for fed cattle with Jersey influence.