The new device, called EchoMRI, was
tested by ARS researchers to measure not only total body fat, but lean tissue
mass, free water mass and total body water in piglets. The research was done
under a grant from the National Institutes of Health, which wants to know if the
new technology could have future applications for human pediatric use.
Standard MRI systems are commonly used to
scan and visualise tissue in humans. However, when used for body composition
analysis, imaging systems are subject to substantial error rates caused by the
interpretation of visual images using software that relies on population
EchoMRI uses a new type of QMR methodology to obtain body
composition results. Its measurement principle depends on the density of
hydrogen nuclei and the physical state of the tissue.
scientist Alva Mitchell at the Animal Biosciences and Biotechnology Laboratory
in Beltsville, Md, tested the device, developed by Echo Medical Systems, to
determine EchoMRI's precision and accuracy in piglets as compared to dual x-ray
(DXA) technology and chemical analysis.
Twenty-five piglets, each weighing between 3.5 pounds and 8
pounds, were screened live, anesthetised, and post-mortem, using a prototype
EchoMRI device for infants. The piglets were also scanned using DXA and then
subjected to chemical analysis.
After DXA scans, EchoMRI screenings, and
chemical analyses were completed, EchoMRI was found to be a precise and accurate
method suitable for measuring piglet whole body composition, total body fat,
lean tissue mass, free water mass, and total body water. While these studies
were conducted on piglets, EchoMRI may be transferable to market-weight pigs.
EchoMRI allows for measurements to be conducted in
only a few minutes without anesthesia or sedation, is radiation-free, and does
not require the subject to remain completely motionless. This facilitates
convenient, low-stress repeated tracking of small changes in body composition
and can be advantageous to researchers to optimise feed utilisation. It could
also help researchers identify high-value hogs for breeding.
â€¢ US Department of Agriculture
â€¢ Agricultural Research Service
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