Comparison of a GE Lunar DPX-IQ and a Norland XR-26 dual energy X-ray absorptiometry scanner for body composition measurements in pigs – <i>in vivo</i>

Abstract

In the context of future growth and performance testing, this study compares corresponding body composition results measured by two dual energy X-ray absorptiometry systems. To test the capability of each device to detect differences among experimental groups widely varying in body composition, 77 pigs from 6 purebred/crossbred groups were used for the experiment. Each pig was scanned consecutively on a Norland XR-26 and on a GE Lunar DPX-IQ. Coefficients of determination were: R²=0.92 for bone mineral content (BMC), R²=0.90 for bone mineral density (BMD), R²=0.94 for lean mass (LEAN), R²=0.92 for fat mass (FAT), R²=0.88 for lean percentage (%LEAN) and fat percentage (%FAT). However, Norland yielded larger values for %FAT and smaller values for %LEAN, BMC, and BMD than Lunar (P<0.001) with the extent of deviation depending on the specific trait and on the breeding group. The deviation in BMC was greater than the deviation in BMD, suggesting different bone detecting algorithms. Both systems revealed similar differences among the breeding groups, and ranked them in the same order based on numerical values. Differences in calibration, bone detection, and software algorithms, however, require a prior crosscalibration to make the body composition data from both systems directly comparable. Finally, they can be used across research centres for the determination of relative and absolute body composition differences among animal groups and individuals.

Use of magnetic resonance imaging to predict the body composition of pigs in vivo

“…It accurately provides information about fat, lean tissue and bone mineral, regarding mass and percentage distribution of the whole body -though it does not provide three-dimensional information about the distribution of the tissues of interest, such as fat, soft lean or bone mineral. DXA has been used successfully to predict body composition in live pigs (Mitchell et al, 1996 and1998a;Scholz, 2002;Suster et al, 2003;Scholz and Foerster, 2006) and carcasses (Mitchell et al, 1998Marcoux et al, 2005) and has been proven for several BW categories (Mitchell et al, 1998a andLukaski et al, 1999;Scholz 2002) (Ruge, 2006;Lö sel et al, 2010). Therefore, by using only one device and software mode, the present study used DXA as quantitative in vivo analysis reference technique to evaluate the potential of MRI as in vivo imaging technique for predicting body composition in live pigs.…”

In vivo body composition in autochthonous and conventional pig breeding groups by dual-energy X-ray absorptiometry and magnetic resonance imaging under special consideration of Cerdo Ibérico

“…DXA (Mitchell et al, 1996;Mitchell et al, 2001a;Lö sel et al, 2010) and MRI (Mitchell et al, 2001b;Tholen et al, 2003) are accurate methods to measure differences in body composition in vivo and carcass traits among different pig lines. Scholz (2002) confirmed these results by calculating high coefficients of determination (R 2 .…”

Effects of l-carnitine supplementation to suckling piglets on carcass and meat quality at market age

“…The following day after each biopsy, pigs were sedated for the estimation of body composition by DXA using the Norland XR-26 device (Norland Corporation, White Plains, NY, USA) as described by Lö sel et al (2010). The DXA technology provides values for bone mineral density, bone mineral content, fat mass and lean mass of the whole body.…”