Comparison of accuracy of intramuscular fat prediction in live pigs using five different ultrasound intensity levels

Abstract

The objective of this study was to evaluate the possibility of prediction of intramuscular fat (IMF) in live pigs using ultrasound method. Moreover, the accuracy of prediction at five different ultrasound intensity levels was investigated. Cross-sectional images of longissimus dorsi muscle (LD) at right last rib area, from hybrid pigs, were taken. Each pig was scanned at the same frequency (3.5 MHz) and at the five different ultrasound intensity levels 70%, 75%, 80%, 85% and 90% of total amplifying of sonograph, using the device ALOKA SSD-500. The video image analysis was used to predict IMF content (ultrasound intramuscular fat (UIMF) 70 to UIMF90). The second day after slaughter, the dissection of right half carcass was done. A sample of LD at the last rib was taken for laboratory analysis of IMF content (LAIMF). Scatter plots with UIMF on the x-axis and LAIMF on the y-axis were constructed to account for individual variability within and between intensity levels. Correlations between LAIMF and UIMF were significantly different from zero (r 5 0.40-0.52), except for correlation between LAIMF and UIMF90 (r 5 0.14). Statistical model with LAIMF (the dependent variable), UIMF (the same model for each intensity level), live weight (the covariates) and sex (the fixed effect) was developed. Coefficients of determination (R 2 ) were 0.33, 0.38, 0.34, 0.25 and 0.17 with UIMF at the intensity level 70%, 75%, 80%, 85% and 90%. Root mean square errors ranged from 0.516% to 0.639%. Standard errors of individual prediction ranged from 0.523% to 0.649%. Goodness-of-fit of the model was also justified by testing the residuals for normality. Although the results are not quite unequivocal in favour of the one intensity level, it seems that intensity levels 75% and 80% are the most suitable to predict IMF in live pigs. Further research is needed, mainly to increase accuracy of collecting, processing and evaluating the sonograms using video image analysis.

Does the Degree of Fatness and Muscularity Determined by Ultrasound Method Affect Sows’ Reproductive Performance?

“…Intramuscular fat in our study was determined in a similar manner as in the study of Bahelka et al [24]. The results of these authors confirm that Aloka SSD-500 device with 3.5 MHz UST-5044 head, with a signal amplification of 80%, allows to determine intramuscular fat content with a very high accuracy.…”

Real-time ultrasound (RTU) imaging methods for quality control of meats

“…Since then, ultrasound technology has become a well-established and widely accepted method for predicting IMF in live cattle and swine (i.e., Brethour, 1994;Herring et al ., 1998;Hassen et al ., 1999bHassen et al ., , 2001Chambaz et al ., 2002;Newcom et al ., 2002;Bahelka et al ., 2009;Schwab et al ., 2010). Recently, the RTU technology for predicting IMF was chosen as one of the 100 Innovations from Academic Research to Real-World Application (AUTM, 2007).…”

Predicting intramuscular fat content and marbling score of pork along the longissimus muscle based on the last rib

“…There are usually around fourteen pairs of ribs along the longissimus muscle of the pig, that is, there are around fourteen different sampling sites available for the determination of IMF content for each pig. Different sampling locations including the last rib (Fernandez et al, 1999;Bahelka et al, 2009;Lo Fiego et al, 2010), the 10th rib (Witte et al, 2000;Lonergan et al, 2007;Rincker et al, 2008), the 3rd/ 4th last ribs (Sather et al, 1996;Fortin et al, 2005;Suzuki et al, 2005b) and the 2nd/3rd last ribs (Lakshmanan et al, 2012) have been adopted in different studies. It is readily obvious that among the different anatomical sites adopted in various studies, the five last ribs are the most sampling sites.…”