Asian Journal of Biological Sciences1996-3351xxxx-xxxxScience International10.3923/ajbs.2017.98.103AhmedYasser Abdelsabourv-KhalafMohamed KhalilFatma 32017103Background and Objective: Mammalian compact bone is composed mostly of Haversian system. Although there are many studies describing the typical Haversian system in mammals, there are few studies conducted on bones from non-mammalian species. The objective of the current study was to investigate the existence of the typical Haversian system in compact bones from reptiles and birds. Materials and Methods: Femora were collected from geckos, Nile monitors, sparrows, ducks and geese. Samples were then, fixed in 10% paraformaldehyde and embedded in paraffin. Paraffin sections were stained with hematoxylin and eosin or Von Kossa and then examined using light microscopy. Results: The current study showed different histological structures of compact bones from studied species and an absence of the typical Haversian system seen in mammals. The compact bone of geckos was mostly avascular, while Nile monitor bone was highly vascular. Sparrow bone showed one side vascular and the other side avascular. The vascularity was represented by primary vascular canals surrounded by a few irregularly arranged osteocytes inside their lacunae forming primary osteons. Bone tissue from ducks and geese were similar and were composed mostly of dense Haversian tissue, while some areas had primary osteons. Conclusion: The compact bone microstructure in some reptile and bird species lack the typical Haversian system described in mammals. This will be of a great importance in developing a better understanding of long bone anatomy and physiology in different species.]]>Foote, J.S.,19113087140Cvetkovic, V.J., S.J. Najman, J.S. Rajkovic, A. Zabar, P.J. Vasiljevic, L.B. Djordjevic and M.D. Trajanovic,201358339351Hillier, M.L. and L.S. Bell,200752249263Martiniakova, M., B. Grosskopf, R. Omelka, K. Dammers, M. Vondrakova and M. Bauerova,2007178290Zedda, M., G. Lepore, P. Manca, V. Chisu and V. Farina,2008Equus caballus) and cows (Bos taurus).]]>37442445Martiniakova, M., B. Grosskopf, R. Omelka, M. Vondrakova and M. Bauerova,20065112351239Martiniakova, M., B. Grosskopf, M. Vondrakova, R. Omelka and M. Fabis,2006Bos taurus) and pigs (Sus scrofa domestica).]]>35167170Castrogiovanni, P., R. Imbesi, M. Fisichella and V. Mazzone,20111163037Dominguez, V.M. and C.M. Crowder,20121498491Giua, S., V. Farina, A. Cacchioli, F. Ravanetti, M. Carcupino, M.M. Novas and M. Zedda,2014Ovis aries musimon) and sheep (Ovis aries aries).]]>877477Bancroft, J.D.,2008Pages: 725Pages: 725Zedda, M., G. Lepore, G.P. Biggio, S. Gadau, E. Mura and V. Farina,201544328332Martiniakova, M., R. Omelka, B. Grosskopf, Z. Mokosova and R. Toman,2009425659Kumas, M. and D. Ayaz,2015Stellagama stellio (Linnaeus, 1758)(Squamata: Sauria: Agamidae) in Barla/Isparta, Turkey.]]>3911601161Ahmed, Y.A., S.A. Soliman and E.A. Abdel-Hafez,201316859864Gudea, A. and A. Stefan,2015Ovis aries), goat (Capra hircus) and roe deer (Capreolus capreolus).]]>39528536De Buffrenil, V., A. Houssaye and W. Bohme,2008269533543Smirina, E.M. and N.B. Ananjeva,200728193204