Gross anatomical studies on the sternum and ribs of Emu (Dromaius novaehollandiae)

In Emu the sternum was large and bowl shaped. The craniolateral processes were short, wide and flattened while presternum, caudolateral processes were absent. The lateral border of the sternum showed oval facets for the ribs from 4th to 5th. In Emu 9 pairs of ribs were present. The 1st, 2nd, 3rd, 8th and 9th pairs were floating type and showed only vertebral ribs, while 4th-5th pairs showed sternal ribs also in addition to vertebral ribs. Each rib consisted of a shaft and proximal and distal extremities. The proximal extremity of vertebral rib showed a head, long neck and tubercle. The ventral ends of vertebral ribs were narrow and pointed while the ventral ends of sternal ribs were wide and flattened and articulated with sternum. The proximal ends of sternal ribs form gliding joints with dorsal extremity of vertebral ribs 4–7.