title: Assessment of nutritional status in rhesus monkeys: comparison of dual-energy X-ray absorptiometry and stable isotope dilution.
abstract: Body composition estimates from dual-energy X-ray absorptiometry and stable isotope dilution ((2)H and (18)O) were compared in 61 rhesus monkeys (Macaca mulatta) from the ongoing long-term energy restriction study at the University of Wisconsin. Their average age was 18.9 +/- 2.5 y/o. Of the animals, 51% were in the energy restricted group and 38% were females. Although the correlation between methods was highly significant for fat mass (R(2) = 0.97, SEE = 0.25 kg or 7.5%, P < 0.0001) and fat-free mass (R(2) = 0.98, SEE = 0.29 kg or 3.6%, P < 0.0001), we observed that dual-energy X-ray absorptiometry underestimated fat mass by 0.67 +/- 0.26 kg (7.5%, P < 0.0001) and overestimated fat-free mass by 0.57 +/- 0.29 kg (20%, P < 0.0001) when compared with isotope dilution. Taken together with data from the literature, the present results emphasize the usefulness of dual-energy X-ray absorptiometry to derive body composition and thus nutritional status in monkeys, but demonstrate the importance of validation experiments for a given DXA model and software.
authors.affiliation: Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA. stephane.blanc@c-strasbourg.fr
authors.forename: Stéphane
authors.initials: S
authors.lastname: Blanc
authors.forename: Ricki
authors.initials: R
authors.lastname: Colman
authors.forename: Joseph
authors.initials: J
authors.lastname: Kemnitz
authors.forename: Richard
authors.initials: R
authors.lastname: Weindruch
authors.forename: Scott
authors.initials: S
authors.lastname: Baum
authors.forename: Jon
authors.initials: J
authors.lastname: Ramsey
authors.forename: Dale
authors.initials: D
authors.lastname: Schoeller
mesh_terms: D015502:Absorptiometry, Photon; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001823:Body Composition / Q000502:physiology*; D005260:Female; D007201:Indicator Dilution Techniques; D007553:Isotope Labeling; D008253:Macaca mulatta / Q000502:physiology*; D008297:Male