Glycoconjugates Study in Surface Secretions of a Fresh Water Edible Catfish, Clarias gariepinus in Response to Clove Oil Anaesthesia: Experimental Investigation

The effects of clove oil anaesthesia on the gills, dendritic organs, and skin of Clarias gariepinus, a locally available fresh water edible catfish, are investigated in this histopathology and histochemistry study. Clove oil is well known for its medicinal values from ancient time as it was/is more commonly used as analgesic and antiseptic. The gills, dendritic organs and skin constitute surface organs in C. gariepinus and remain in direct contact with the surrounding water and provide greater surface area of absorption for any xenobiotics including the clove and were thus chosen for investigation. Clove oil, derived from the flower buds, leaves, and stems of the Syzygium aromaticum plant, has lately been introduced as an efficient anaesthetic agent in the fishing business to address a variety of purposes. C. gariepinus of total length 30 ± 2 cm and total weight 200 ± 5 g were exposed to various concentrations of clove oil (LOBA CHEM. PVT. LTD, MUMBAI, Minimum assay 85%) in the range of 0.07 ml/l to 0.3 ml/l. During clove oil exposures, C. gariepinus exhibited irregular swimming, bubbling, rubbing against the side and bottom walls of the glass aquarium, and protrusion of the head above the water surface. Fish, on the other hand, become static and horizontal as their opercular motions cease and their balance is lost. Clove oil anaesthesia changes the mucogenic properties of all surface organs, causing more Alcian Blue pH 2.5 positive mucus and slime to be secreted on the surface. Other harmful indications of clove oil anaesthesia in C. gariepinus include wear and tear of the epithelial linings of the gills, breakdown of vascular components, leaking of blood on the surface of dendritic organs, and lifting of the gill epithelium.