Macro-and micromorphological studies on the laryngeal mound of Turkey

Abstract EN

Ten turkey birds were used to study the morphological features of the laryngeal mound grossly, histologically and by scanning electron microscopy.

The laryngeal mound appeared to consist of two adjoining, raised; quadrilateral mucosal plates located in the floor of the pharynx.

It divided into two parts by laryngeal inlet which was V- shaped.

The length of the mound and its inlet measured about 20.45 mm and 13.6 mm respectively.

By SEM, the dorsal surface of the laryngeal mound appeared scaly and carried few small conical papillae at its caudal part.

At the caudal end of mound, the laryngeal papillae arranged into two rows of the papillae; each row included 20 – 24 conical papillae.

The rostral row consisted of long spinous conical papillae which carried numerous fine elongated papillae toward their bases and displayed two large gaint papillae on the midline.

The caudal row had short conical papillae, their bases were surrounded by numerous thin thron-like papillae.

Microscopically, the laryngeal mound covered with stratified squamous epithelium and gradually transformed to pseudostratified ciliated columnar epithelium (respiratory epithelium) at the laryngeal inlet.

The cricoarytenoid salivary glands were presented in the lamina propria of the lateral part of the laryngeal mound.

Their ducts penetrated the mucosa to open into the pharyngeal cavity.

Each gland was formed from a varying number of units, each unit comprising many tubules, opening into a common cavity and possessing a common duct.

The glandular tubules lined by mucous secreting cells showing strong PAS positive reaction.