Morphological comparison of the chukar partridge (Alectoris chukar) and Japanese quail (Coturnix coturnix japonica) syrinx

Syrinx is a voice device and shows structural and functional differences between bird species. This study aimed to investigate morphological and histological structures of the syrinx in chukar partridge (Alectoris chukar) and Japanese quail (Coturnix coturnix japonica). In the present study, ۱۲ male chukar partridges and ۱۲ male Japanese quail were used. The syrinx tissues were photographed by digital camera and fixed in formaldehyde solution. Five syrinxes were stained with methylene blue to make the syrinx rings distinct. After anatomical examination, tissues were passed through alcohol series, cleaned in xylene, and embedded in paraffin blocks. The blocks were cut and obtained sections were stained with Crossman modified triple staining and examined under camera attached light microscope. The syrinx of chukar partridges and Japanese quail consisted of cartilaginous tracheasyngeales and bronchosyngeales in the region of bifurcatio trachea and at the level of basis cordis. The tracheal rings constituting syrinx were counted three in chukar partridge and four in Japanese quail. The bronchial rings comprising syrinx counted nine in chukar partridge and eight in Japanese quail. In the histological examination, the pesullus structure was hyaline cartilage and calcificated with increasing ages being covered by pseudostratified columnar epithelium. The results of the study suggested that chukar partridge and Japanese quail syrinxes have some morphological differences compared to the other bird species; but, anatomically and histologically similarities to many bird species.