Posthatching developmental studies on the tongue and laryngeal entrance of the common quail (Coturnix coturnix, Linnaeus, 1758) in different five age-stages.

The present study represents the first trial to characterize the ultrastructural of five ages of Coturnix coturnix. Lingual nail had membrane that differ in number among five studied ages. Filiform papillary system had four caudally directed papillae types; small (apex, rostral, and median part of body in 1 day, body in 10 and 20 days), long (apex and rostral part of body in 10 days, tip and two lateral area in 20, 30, 40-days, lateral border in 1 and 10 days, two lateral area of body in 40 days), broad (median area of body in 20, 30, 40 days). Scales on the ventral surface of apex, mound. Lingual sulci on the apex and body without reaching tip in 10, 20, 30, 40-days while, in 1 day the body had ridge caudally. Three papillae on posterior part of lateral border of body. W-shape crest had papillae on its median part while, its lateral part had two giant papillae on each side. Dorsal giant papillae terminated caudally with six processes, while ventral papillae terminated caudally with three processes. The unique root appearance, at 1 day had four papillae while in 10-day, it had one papilla however in 20, 30, 40 days, it had T-shaped ridge. Mound had one longitudinal row on each side of cleft and two transverse papillary rows at its caudal border and additional row at 40-days. Our findings exposed unique structural and functional characterizations of lingual and laryngeal entrance that reflected with feeding behavior.