Gross anatomy, histology, histochemistry and scanning electron microscopy of tongue, cranial larynx, and associated glands in broiler chicks
Abstract
In 07, 11, 18, 25 and 32 days age group broiler chicks the tissues were collected from the apex,
body, root and caudal lingual papillae of the tongue, anterior portion, middle portion, posterior portion and
pharyngeal papillae of the cranial larynx and associated glands for the gross anatomy, histology,
histochemistory and scanning electron microscopic studies of the tongue. Grossly, the tongue was divided
in to 3 parts i.e. apex, body and root. In between the body and root of the tongue a row caudal lingual
papillae was present. Histologically, the dorsal and ventral surface of the tongue was lined by stratified
squamous type epithelium except at the ventral surface of the apex. The glands were anterior and posterior
lingual glands which showed different affinity for the various types of mucopolysaccharides, mucins and
glycogen. Scanning electron micrograph presented desquamated cells on the dorsal surface of the apex and
body whereas on the root these desquamated cells were absent. Grossly, the cranial larynx was presented 2
laryngeal mounds, laryngeal cleft, laryngeal fissure, middle rows of papillae and 2 rows of pharyngeal
papillae. Histotologically, the dorsal surface of the cranial larynx was lined by stratified squamous non
keratinized type epithelium and the ventral surface was lined by respiratory type epithelium. The glands
were mucous type and showed various concentrations of acidic mucopolysaccharides, mucins, weakly
sulfated acidic mucopolysaccharides, hyaluronic acid and sialomucins. The scanning electron microscopy
presented well defined structure of laryngeal mounds, cleft and pharyngeal papillae. The different patterns
of micropliacae were evident on the surface of the middle and pharyngeal papillae.