Macroscopic study of syrinx in the common bulbul (Pycnontus barbatus) and indigenous pigeon (Columba domestica)

Abstract

In this study, syrinx of five male common bulbuls (Pycnontus barbatus) weighing (25.93 ±0.89 g) and five male indigenous pigeons (Columba domestica) weighing (286±0.73 g) were examined for macroscopic structure. The results showed the anatomical positions of the syrinx. The syrinx was observed ventral to the esophagus exactly on the base of heart in the common bulbul, whilst in pigeon; the syrinx was hidden by the heart. The morphological structure of the syrinx in both species could be classified as tracheobronchial type. The number of tracheo-syringeal rings could not be determined certainly in common bulbul, while in the pigeon, tracheo-syringeal part was composed of the two cartilaginous rings (T1 and T2). These two cartilaginous rings were different in diameters, and joined each other at middle. In the common bulbul, tympanum which is the middle part of syrinx has the bilateral bulla; while tympanum of pigeon does not have bulla. Furthermore the broncheo-syringeal cartilages form the caudal part of syrinx, which are composed of five C-shaped rings in both species. The caudal syringeal part of common bulbul has interbronchial foramen, which absents in pigeon.