Histological study of the gall bladder of the common quail (Coturnix coturnix)

The objective of this investigation was to study the histological structure of the gall bladder in the common quail (Coturnix coturnix). Samples were obtained from six male and six female healthy adult common quail. Tissue sections were stained with haematoxylin and eosin. Histological results showed that the overall histology of the gall bladder of the common quail is similar to that in the chukar partridge except for the goblet cells. No significant sex-based differences were found. The gall bladder was composed of tunica mucosa, tunica muscularis and tunica serosa or tunica adventitia. The tunica mucosa was mainly lined with simple columnar epithelium which was covered by a continuous striated border of microvilli. Goblet cells were observed among the epithelial cells. The tunica mucosa formed some folds which appeared to be regularly distributed over the whole gall bladder luminal surface and were mostly isometric. Deep invaginations of the surface epithelium were observed to have grown down into the underlying mesenchyme, showing a tubular gland-like appearance. The muscularis mucosa was absent. The thin lamina propria-submucosa contained loose connective tissue which consisted of numerous diffuse lymphatic tissues, but no glands were observed. The tunica muscularis consisted of a thin circular layer of smooth muscle fibres. The loose connective tissue of the tunica serosa or adventitia was made up of adipose tissues and blood vessels. It is concluded that the histological structures of the gall bladder of the common quail are similar to those of the chukar partridge except for the presence of goblet cells among the epithelial cells of the tunica mucosa.