Pork carcass evaluation with an automated and computerized ultrasonic system

Carcass data were collected from market barrows and gilts (n = 325) slaughtered at a commercial slaughter facility in Canada to estimate carcass composition from longitudinal average fat depth and muscle depth measured automatically by a computerized real-time ultrasonic system. Similar and other ultrasonic measurements were also made manually from the same carcasses for comparison purposes. Results of regression analysis indicated that the optimum measurements were hot carcass weight, automatic average fat depth, and muscle depth made from the carcass longitudinal scans between the 10th rib and last rib in predicting weight of lean (defatted, deboned four lean cuts, R2 = .88, RSD = 1.19) and weight of grade lean (weight of lean plus skinless square-cut belly and side (spare) ribs, R2 = .92, RSD = 1.09). The automatic depth measurements provided more precise factors for estimation of lean than the careful manual measurements of fat depth, muscle depth, and loin muscle area. Manually measured loin muscle area was not required (P > .05) after hot carcass weight, manually measured fat depth, and loin depth were included in the models for predicting weight and percentage of any of the dependent variables. These results suggest that the automated and computerized ultrasonic system tested in this study can be used as an efficient and objective tool in a meat animal value-based marketing system.