DEVELOPMENT OF THE TYPICAL CERVICAL VERTEBRAE IN THE WHITE NEW ZEALAND RABBIT (ORYCTOLAGUS CUNICULUS)

Abstract

In order to study the pattern of ossification of the components of the postcranial axial skeleton of the white new Zeeland rabbit, intact embryos were isolated between days (d) 13 and 28 of pregnancy, and postnatal till three months old rabbit. All specimens were fixed in 95% ethanol for at least one week, a group was bulk-stained using alizarin and Alcian blue, in order to stain bone and cartilage, respectively, and cleared. Another group was histologically stained with H&E and Mason Trichrome. A third group was examined with CT and X-ray. The time of the first appearance of ossification centers of these prenatal and postnatal specimens was analyzed. The findings demonstrated that, with the exception of the atlas and axis, all of the cervical vertebrae studied had similar growth patterns. The time of appearance of the various centers of ossification in the skeletal elements studied proceeded in a similar order to that described by previous authors, although there were some discrepancies in the exact time of the first appearance of certain ossification centers. Secondary ossification for the epiphysis cranialis and caudalis (the bony collar) appear in cervical region and then extend in cephalocaudal direction till complete appearance at the age of 45-days old rabbit. The data presented here provide useful baseline information on the normal sequential pattern of ossification in the typical cervical vertebrae and the characteristic growth pattern of the individual components in the rabbit.