Survey on Anesthetic Effects in Different Concentrations of Eugenol on Fingerlings and Broodstocks Caspian Roach (Rutilus caspicus)

Inroduction & Objective: Due to the side effects of chemical drugs, in recent years, the use of herbal medicines and their compounds in fish has been widely considered. In the present study anesthetic effects of eugenol has been studied in fingerling and broodstock Caspian roach (Rutilus caspicus). Material and Methods: In this regard, 100 fingerling with average weight of 10.4 ± 3.1 g and 75 broodstock Caspian roach with average weight of 60.5 ± 4.4 g prepared. After adaptation anaesthetic and recovery status were evaluated for each group of the fingerlings and broodstock in concentrations of 10, 20, 40, 80 and 100 ppm of eugenol. To evaluate the side effects of this drug, gill and kidney histology analysis were performed in the fish that anesthetized with 100 ppm of eugenol. Result showed eugenol in concentrations of 40 – 100 mg/l can induce anesthesia in less than 3 minutes in broodstocks. On the other hand, fingerlings fish were anesthetized in less than 3 minutes in all concentrations of 10 – 100 mg/l eugenol. For all studied concentrations of eugenol the recovery times were recorded in both fingerlings and broodstocks fish less than 5 minutes. In histological analysis of fingerlings fish that anesthetized with 100 mg/l of eugenol, epithelial lifting of secondary lamella in gill was recorded, also no histopathologic abnormality was observed in kidney tissue. Based on this study, eugenol can be used as a safe anesthetic drug in concentrations of 40 to 100 ppm in the Caspian fish.