The effects of probe type and intensity of ultrasound on accuracy of intramuscular fat prediction in longissimus dorsi muscle of pigs

Abstract

This study evaluates the possibility of intramuscular fat prediction in live pigs using two different ultrasound probes (3.5 and/or 5.0 MHz) at three various levels of total ultrasound intensity. One hundred and forty-five hybrid pigs were weighed and scanned one to three days before slaughter by device ALOKA SSD 500. Each pig was scanned by both probes but at different levels of intensity. Cross-sectional images of longissimus dorsi muscle were processed by video image analysis for prediction of intramuscular fat content. Day after slaughter a sample of longissimus dorsi muscle was taken for laboratory analysis of true content of intramuscular fat. Correlation coefficients between predicted and true IMF content were calculated. Better results were achieved by probe 3.5 MHz than 5.0 MHz. Statistically significant correlation was found between analyzed IMF and estimated one at intensity of 80 % (r = 0.31), less significant at intensity of 75 % (r = 0.20). After the improvement of accuracy of data proccessing and evaluation of sonographic images the ultrasound prediction of intramuscular fat in live pigs is feasible.