Abstract
Abstract
Despite the fact that the gestational period is essentially shorter, the rabbit development is homologous to the human in numerous ways. This study concentrates on the development of the sacrum and tail in the white New Zealand rabbit, as a step forward to allow the rabbit as an examination model for the human research. Specimens were collected prenatally (30) and postnatally (30). The specimens were stained for bone and cartilage using Alizarin Red and Alcian blue. Three primary centers one for the body and two for the neural arches appeared on the day 22 of gestation. Two weeks after birth, the proximal and distal epiphysis show secondary ossification center as a bony collar at the both ends of the body. Three months after birth, the rabbit sacrum showed a complete fusion occurs between the primary and secondary ossification centers of the vertebral body. The distal ends of all processes were ossified. The four or five chief caudal vertebrae have to a great extent the same developmental pattern as the sacral vertebrae. From eight to ten were more straightforward vertebrae. The most posteriorly put vertebrae being just bars of bone, with extended articular extremities. The chevron was absent in the tail the rabbit. The ossification centers of the tail appear in a progressive manner from cranial to caudal with the last four caudal vertebrae were ossified in the middle by the end of the 2nd week after birth.
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Key Words: Rabbit, Sacrum, Tail, Development, Double staining.

Key words: Rabbit, Sacrum, Tail, Development, Double staining.