The gross anatomy of larynx, trachae and syrinx in the long-legged buzzard (Buteo rufinus)

Abstract

Five long-legged buzzards (Buteo rufinus), weighing 475-570 g, were used in this study. It was determined that long-legged buzzards' larynx is composed of three different cartilages. Among these cartilages, the cricoid and procricoid cartilages were single and the arytenoid cartilage was double. The partially ossified corpus and ala of the cricoid cartilage were connected with cartilaginous plate. Trachea was formed up of complete cartilage circles. The tracheal cartilages were notched in dorsal and ventral directions and a number of the tracheal cartilages inter-mingling one another were between 89-96. Syrinx, which was covered with the inter-clavicular air sac, was in contact with basis cordis. It was observed that there is tracheobronchial type syrinx in long-legged buzzard and this syrinx is formed by two different cartilage groups named as the cartt. tracheosyringeales and cartt. bronchosyringeales. The first cartilage rings of the cartt. tracheosyringeales formed the tympanum. The tympanum, cartt. tracheosyringeales and cartt. bronchosyringeales were created of three, two or three and four cartilage rings, respectively. Membrana tympaniformis lateralis and medialis, two pairs of thin membranes constituting voice formation, also determined in long-legged buzzard. Membrana tympaniformis lateralis was observed to be very short between the first and second cartilage rings of cartt. bronchosyringeales. Although the instrictic syringeal muscles were not present in long-legged buzzard, the sternotracheal and tracheolateral muscles, expressed as extrinsic syringeal muscles, were evident. In this study, which is expected to give contribution to veterinary anatomy literature, the similarities and differences in larynx, trachea and syrinx of long-legged buzzard with other bird species were exposed.