Ecology, Environment and Conservation Paper

OBSERVATIONS ON THE FUNCTIONAL SIGNIFICANCE OF HISTO- LOGICAL AND HISTOCHERNICAL COMPONENTS IN OESOPHAGUS OF A FRESHWATER FISH 4 CLARIAS BATRACHUS

G. Benarjee, B. Laxma Reddy, G. Rajender, M. Swamy and N.J. Rama Rao

Abstract

The study has been made to elucidate the histomorphological and histochemical components in the oesophagus of freshwater cat fish, Clarias batrachus. The histological observations revealed that the oesophagus consists typical four layers i.e., mucosa, submucosa, muscularis layer and serosa.The mucous layer consists of undifferentiated cells. The epithelial cells differ in their structure from anterior to the posterior region of the oesophagus.The circular muscle bundles occupy major part and impart abundant thickness to the oesophagus. Due to this thickness the oesophagus has attained contractile and expansion ability.The histochemical tests applied on the oesophageal sections revealed the presence of elastin, collagen, acid mucopolysaccharides, neutral mucopolysaccharides and hyaluronic acid.The weak and strong acid mucopolysaccharides were also identified in the esophagus.The occurrence of sialomucins and sulphates mucous substances revealed their significance in the physiological function of oesophageal part of digestive tract.