author(s)
OR Sathyamoorthy, R Richard Churchill and N Karunakaran

abstract
The sternum of blue and yellow macaw was comprised of a manubrium sterni or sternal spine, a body and a sternal crest. The manubrium sterni was thick upwardly bent spine-like process arose only from the ventral edge of the cranial border. At the base of the sternal spine on left side, a large pneumatic foramina was noticed. The body of the sternum was rectangular in shape. In the cranial half presented numerous small pneumatic foramina. Two large oval foramina, the foramen ovale were located near the caudal border. The cranial border of the sternum was convex, thick and semicircular in shape. The craniolateral process was very short, roughly quadrilateral in shape and dorsolaterally directed. The lateral borders presented five transversely placed thin and short articular cylinders. The caudolateral process was short, broad and thin. It extended up to the caudal border of the sternum and fused with it and formed caudal border of the sternum. The sternal crest was well developed, triangular in shape, and projected from below the sternal spine. The cranial border of the sternal crest was the cranial most structure of the sternum. It formed a steep backward curve and extended up to the caudal border of the sternum. The processus thoracicus was absent.