Effects of hibernation on bone in yellow-bellied marmots

Figure 2.1: The gray highlighted on this femur outline is the region used for histology. After embedding, sections were cut perpendicular to the long axis of the bone. Sections were cut starting at the midshaft……………………………………… 26 Figure 2.2: Femur cross section, where the grey lines represent the location of anatomical octants. Red boxes indicate location of images obtained from each octant for analysis of osteocyte lacunar properties. Note: size representation of images in comparison to cross section size may vary…………………………………...… 26 Figure 2.3: Osteocyte lacunae data was collected in three groups. Lacunae with a partial halo (left), lacunae with no halo (middle), and lacunae with a halo (right). ………………………………………………………………………………….. 27 Figure 2.4: Refilling cavity (left), resorption cavity (right)…………………………….. 28 Figure 2.5: Marmot tibia next to the fixture used for micro-CT………………………... 29 Figure 2.6: Micro-CT scout view of a marmot tibia with evaluation region highlighted. ………………………………………………………………………………….. 30 Figure 2.7: 3-D reconstruction of the region of a marmot tibia scanned with µCT……. 30 Figure 2.8: Example of a digitized femoral cross section used to calculate cross sectional properties. The neutral axis and point furthest from the neutral axis, as well as the x and y distances from the centroidal axis to the point furthest from the neutral axis and moments of inertia were determined by the macro…..……………….. 32 Figure 2.9: Typical load-deformation curve, red X marks the failure point. Stiffness is denoted as S on the curve and yield force is denoted as F y .