Body Composition Measurement
Total body fat, lean, and bone mineral content is measured by dual x-ray absorptiometry (DXA) using a PIXImus instrument (General Electric). The measurements are performed in a CNRF procedure room. Each mouse is lightly anesthetized by placing it in a chamber with isoflurane (5% and 95% oxygen). As soon as the mouse is sedated it is placed on a disposable PIXImus measuring tray for proper alignment and is fitted with a loosely-fitting nose cone for administration of isoflurane (2% isoflurane) until the measurement is complete. The mouse is inserted into the instrument for measurement (approx. 5 minutes) and then returned to its cage to recover. If you prefer, you may use an injectable anesthetic.