Ultrasonographic in vivo estimation of back fat depth and Longissimus dorsi area in Iberian pigs

Real-time ultrasound is a useful technology for measuring carcass composition in live animals and to select future seedstock for carcass merit. Therefore, the objective of this study was to evaluate the use of ultrasound to predict the amount of fat and muscle in Iberian pigs. A total of 163 Iberian pigs were ultrasonically scanned one day before slaughter, and carcass composition was also determined in the slaughterhouse. Ultrasound and carcass traits included the three lays of back fat and Longissimus dorsi (LD) area, at the 10 th and 14 th rib levels. Data were analyzed by regression and correlation procedures using SAS. Results indicated a positive correlation between ultrasound and carcass traits at both rib levels. Regression results indicated that ultrasound measurements had smaller values than carcass measurements. Correlations between ultrasound back fat measurements and carcass, ham, and foreleg weights were positive, but they were negative with respect to LD weight. The highest correlation with LD weight was LD area at the 14 th rib level.