The accuracy of the use of two probes (UST-586-5 MHz and UST-556 tu-7.5 MHz) for
predicting the carcass composition were used in 36 lambs of Churra Bragançana breed
ranging in body weight from 26 to 47kg. Comparison between the ultrasonic
measurements assessed in live lambs with the same measurements taken on carcass were
established. The best relationship obtained were between the ultrasonic measurements
assessed with 7.5 MHz probe on last rib and the same fat thickness measurements taken
on carcass. Between 41 and 86tm of the variation in the weight of carcass components
were accounted for by variation in body weight and the ultrasonic measurements
