A SIMPLE ULTRASOUND INSTRUMENT IS AN EFFECTIVE TOOL IN PREDICTING BODY-COMPOSITION OF LIVE PIGS

Assessing changes in body composition of live animals is important for studying nutrition, physiology, or growth of animals. The use of the ultrasound technology to estimate in vivo body composition of animals has a long history. Numerous ultrasound instruments with varying compl exity are currently available for use in swine research, but there see m to be considerable variations among complex, rear-time ultrasound in struments in the efficacy of estimating body composition. The use of c omplex ultrasound instruments can be justified only if their additiona l costs of instruments and operation are more than offset by benefits in extra precision. Data collected from 177 crossbred pigs were used t o describe the relationship between backfat thicknesses (BF) measured using a simple ultrasound instrument and carcass traits and lean. The average ultrasound BF was highly correlated with carcass BF and percen tage of lean, and multiple regressions based on ultrasound BF and live measurements accounted for 78 to 83% of variation in predicting carca ss BF and lean. The results indicate that the use of a simple ultrasou nd instrument capable of measuring only BF is a practical and effectiv e means to estimate carcass traits and composition of live pigs.