Light and electron microscopic studies of phyarynx and osophagus of barbussharP~fish

The histomorphological studies of Pharynx and oesophagus ofbarbus Sharpyi have been reported. The pharynx has two lateral pharyngeal bones each with 3 rows of pharyngeal teeth arranged in the dental formula: 20305-50302 in it's cranial part. The epithelium ofpharynx was thick nonkeratinized stratified type and 144.6+21.2m thick. The mucous cells were seen scattered in this epithelium. The weredeep branched crypts in epithelium that depth and the branching of crypts increased near the oesophagus. The bases of the cryptste1nainated into large mucous acini. Electron microscopic study showed that the mucous columnar cells of pharynx and oesophagus glands cQntained large amounts of large secretory granules. The basal cells also seen in these glands . The apical cytoplasm of basal cells containemucous g1anules, which shows that the basal cell are able to change to mucous cells. The epithelium had taste buds. The muscularis mucosa was absent. Tunica muscularis comprised of striated muscle cells. Oesophagus has two strong and thick sphincters ie, cranial or pharyngeooesophageal and caudal or bulbo-oesophageal. The mucosal epithelium was nonkeratin~zed stratifiedsquamous type and had a few scattered goblet cells and a few taste buds in the cranial part. Numerous oesophageal mucous glands were seen in lamina properia-submucosa. Seromucous glands were seen in the ternainal portion of oesophagus, near the opening of swim bladder. Tunica muscularis comprised of striated muscularis tissue, which was arranged in two layers, thin internal (longitudinal) andthick external (circular). In tenninal portion, the scattered smooth muscle fibers were also seen. At the point connection of oesophagus with intestinal bulb, arrangement of cellular muscle fibers was reversed.

Keywords:

Barbus sharpyi , Pharynx , Oesophagus , Histology