Proximal tibiotarsal cancellous bone mechanical properties in broilers

Broiler leg abnormalities cause significant economic losses through decreased body weight gains and increased mortalities. The mechanical properties of poultry cancellous bone could be contributory factors in lameness caused by these abnormalities. For example, a decreased elastic modulus indicates that the bone is less resistant to deformation. In the subchondral growth plate area, decreased deformation resistance could lead to greater incidences of damage to the growth plate, resulting in morphologic changes causing lameness. The objective of this study was to examine the effects of age and of altering protein and amino acid nutrition on body weight, bone ash content, and cancellous bone compressive strength characteristics (strength, elastic modulus, and resilience). Body weights increased as age increased, regardless of other factors. Bone ash content typically declined by nine weeks of age. A reduction in strength, elastic modulus, and resilience was seen at nine weeks of age with elastic modulus in the lateral region of proximal tibiotarsal cancellous bone being the exception. In general, bone ash content directly affected the measured bone strength parameters, i.e., a decrease in bone strength parameters occurred when bone ash content decreased.