Interrelationships between Densitometric, Morphometric, and Mechanical Properties of the Tibia in Turkeys

The aim of the study was to evaluate the interrelationships between parameters assessed with the use of a computed tomography technique and mechanical properties of the tibia in male turkeys at different stages of skeletal development. Healthy male turkeys (N = 120) were kept under standard rearing conditions and randomly selected from the farm flock at the age of 4, 8, 12, and 20 weeks of life to obtain a right tibia for the investigations. Using a computed tomography technique, volumetric bone mineral density of the trabecular and cortical bone, mean volumetric bone mineral density, total bone volume, and cortical bone area of the tibia were estimated. Geometrical properties, such as cross-sectional area, second moment of inertia, mean relative wall thickness, and cortical index, were derived from computed tomography measurements of horizontal and vertical diameters of the tibia in the midshaft. Using a three-point bending test, the mechanical parameters were estimated in terms of maximum elastic strength and ultimate strength of the tibia. A Pearson’s correlation coefficient was determined for all the investigated variables. The obtained results showed age-related changes of the skeletal system in growing turkeys in terms of morphological, densitometric, and mechanical properties. Positive correlations among the investigated parameters were found, except for mean relative wall thickness and cortical index, which were negatively correlated with these parameters. Morphometric and densitometric parameters assessed with the use of computed tomography were significantly correlated with maximum elastic strength and ultimate strength proving the usefulness of this technique for predicting mechanical properties of bones. In conclusion, this study showed computed tomography as a precise and non-invasive technique for the determination of skeletal system properties that may serve to monitor in vivo the dynamics of the changes of bone metabolism in studies on physiological, nutritional, and pharmacological factors influencing the skeletal system.