The ossification of the vertebral column, thorax and sternum in the quail (Coturnix coturnix japonica)

The ossification centers onset of the quail vertebrae, ribs, and sternum in embryos and hatchling birds was studied. Specimens were cleared, stained with Alcian Blue and Alizarin Red S and examined using stereomicroscope. The chondral rudiments of the vertebrae were observed at the ۶th day of incubation (E۶). The osteogenesis of the vertebrae was accomplished with both perichondral and endochondral ossifications. The cervical vertebrae began to ossify at E۹-E۱۰, whereas the thoracic ones began at E۱۰-E۱۱. The synsacral vertebrae began to ossify at E۱۱-E۱۳. In the caudal vertebrae, ossification was observed at E۱۴ and in the pygostylous ones, at E۱۵. The true ribs began to ossify at E۷, whereas the ۱st and the ۲nd ribs began to ossify at E۹ and E۸, respectively. The uncinate processes were ossified late at E۱۵. At E۱۳, ossification was observed in the caudo-lateral process of the sternum. At E۱۴, the cranio-lateral process of the sternum began to ossify, whereas late at and after hatching ossification was observed in the carina and the sternal body, respectively. The data presented here provide useful baseline information on the normal sequential pattern of ossification in the vertebral column and thoracic cage in quail.

Keywords:

Ontogeny , Osteology , Quail , Skeletal development