Bone Abstracts

Considering limited information on skeletal system properties in emu (Dromaius novaehollandiae), the aim of this study was to determine morphological and densitometric parameters of tarsometatarsus obtained from adult males (N=6) and females (N=7). The study was performed on birds reared at the Department of Poultry and Ornamental Bird Breeding of Western Pomeranian University of Technology in Szczecin, Poland. Male and female emu were slaughtered to obtain left tarsometatarsus for analyses. Bone weight, relative bone weight and bone length were determined. Using quantitative computed tomography (QCT) technique and self-determined regions of interest

(ROIs), volumetric bone mineral density (vBMD) of trabecular (Td) and cortical bone (Cd), as well as cortical bone area (CBA) were measured. Td was determined in proximal epiphysis, while Cd was measured in the midshaft. Automatically defined ROIs were used to determine mean Td, mean Cd and mean CBA. Moreover, total bone volume (Bvol) and mean volumetric bone mineral density (MvBMD) were determined. All QCT measurements were performed using LightSpeed VCT scanner (GE Medical Systems, USA) and OsiriX software for Mac Pro 29-ZRL computer. Statistical analysis was performed using paired Student t-test and P<0.05 was statistically significant. Final body weight was significantly higher by 25% in females than in males (P=0.01). Significantly higher values of bone weight, bone length, Bvol, and mean CBA of tarsometatarsus were found in females, when compared to males (P<0.01).

In conclusion, this study has shown sex-related differences of body weight and morphological properties of tarsometatarsus in emu, while the investigated densitometric parameters were not sex-differentiated. This study provided data on morphological and densitometric properties of tarsometatarsus in emu. The obtained results indicate that emu may serve as an experimental model for further studies on bone metabolism regulation in vertebrates with the use of physiological, environmental, pharmacological, nutritional and toxicological factors influencing skeletal system properties.