Accuracy of real-time ultrasound measurements of total tissue, fat, and muscle depths at different measuring sites in lamb1

Abstract

Accuracy of live ultrasound measurements to evaluate the total tissue depth (GR), as well as fat and LM depths at different scanning sites, was studied in 96 purebred Suffolk and Dorset lambs of both sexes slaughtered between 36 and 54 kg of BW. Before slaughter, 7 real-time ultrasound measurements were taken on lambs: fat and LM depths between the 12th and 13th ribs (transverse) and between the 3rd and 4th lumbar vertebrae (transverse and longitudinal), and GR. After slaughter, the measurements equivalent to ultrasound measurements were taken on digitized images of the cuts on the left half carcass of each lamb. Ultrasound GR and fat depth measurements were closely correlated with the corresponding carcass measurements (0.76 < or = r < or = 0.81). Ultrasound GR measurement exhibited a large error of central tendency, but the level of error due to the disturbance (ED) was comparable with fat depth measurements (ED = 8.5%; residual SD = 2.24 mm; CV of residuals = 9.5%). Ultrasound fat depth measurements were more accurate between the 12th and 13th ribs (error due to regression = 1.20; ED = 0.82) than between the 3rd and 4th lumbar vertebrae (error due to regression = 5.58 and 5.4; ED = 1.10 and 0.93, transverse and longitudinal, respectively), mainly due to image interpretation errors in the lumbar region. Measurements of LM depth demonstrated low variability in the population under study (SD = 2.6 mm), and these ultrasound measurements showed low correlation with the corresponding carcass measurements (0.34 < or = r < or = 0.43). The results of this study demonstrated that ultrasound measurements were more accurate for evaluating fat depth and the GR measurements than for estimating LM depths. Ultrasound GR measurement is a promising measurement, especially where carcass grading systems are based on this carcass measurement.

Bayesian inference of genetic parameters for ultrasound scanning traits of Kivircik lambs

“…Similar results were reported for SBFT in other breeds (Karya, Karacabey Merino and Kivircik) reared in Turkey (Cemal et al, 2007;Yilmaz et al, 2014). Mean of MD in this study was lower than the mean values reported in some meat-type breeds (Theriault et al, 2009;Slosarz et al, 2011). This was most probably due to the fact that measurements were taken at a relatively early age as part of our breeding program compared with other breeding programs.…”

“…The mean of BFT measurements is within the range of values reported by various researchers (Cemal et al, 2007;Theriault et al, 2009;Slosarz et al, 2011;Esquivelzeta et al, 2012;Santos et al, 2014). Similar results were reported for SBFT in other breeds (Karya, Karacabey Merino and Kivircik) reared in Turkey (Cemal et al, 2007;Yilmaz et al, 2014).…”

The relationship of ultrasound measurements taken from two different anatomical regions to carcass traits and chemical composition of the carcass in Karayaka lambs

“…Supporting the current results, various authors have noted high positive correlations of UFT with live weight (7,22,23,28), cold carcass weight, bone amount (10), and meat amount (2,10). The fact that UFT measured from both regions in this study had a high correlation with live weight, warm carcass weight, cold carcass weight, and bone and meat amounts means that UFT may be used for a primary estimation of carcass traits (4,9). It was also reported by Agamy et al that ULW values have a significant positive correlation with live weight (7); the same was reported for cold carcass weight by Ripol et al (10).…”

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

“…In recent years, several works have been published that clearly show that the RTU technique allows good estimates of the composition of the carcass to be obtained. These studies aimed to predict carcass composition in adult animals (Hopkins et al ., 2007;Teixeira et al ., 2008), market lambs Leeds et al ., 2008;Orman et al ., 2008;Thériault et al ., 2009;Emenheiser et al ., 2010;Orman et al ., 2010) or light carcasses (Ripoll et al ., 2009). Although the results obtained were generally good, attention must be paid to the factors that lead to inaccuracy in the RTU technique when used for small ruminants.…”