INTERSPECIES DIFFERENCES IN BONE-COMPOSITION, DENSITY, AND QUALITY - POTENTIAL IMPLICATIONS FOR IN-VIVO BONE RESEARCH

This study compares bone composition, density, and quality in bone sam ples derived from seven vertebrates that are commonly used in bone res earch: human, dog, pig, cow, sheep, chicken, and rat. Cortical femoral bone samples were analyzed for their content of ash, collagen, extrac table proteins, and insulin-like growth factor-I. These parameters wer e also measured in bone powder fractions that were obtained after sepa ration of bone particles according to their density. Large interspecie s differences were observed in all analyses. Of all species included i n the biochemical analyses, rat bone was most different, whereas canin e bone best resembled human bone. In addition, bone density and mechan ical testing analyses were performed on cylindrical trabecular bone co res. Both analyses demonstrated large interspecies variations. The low est bone density and fracture stress values were found in the human sa mples; porcine and canine bone best resembled these samples. The relat ive contribution of bone density to bone mechanical competence was lar gely species-dependent. Together, the data reported here suggest that interspecies differences are likely to be found in other clinical and experimental bone parameters and should therefore be considered when c hoosing an appropriate animal model for bone research.