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Anaesthetic effects of essence, water and water-alcohol extractions of clove flower (Eugina caryophillata) were studied on rainbow trout (Oncorhynchus mykiss) at water temperatures of 5°C, 15°C and 20°C and pH of 6,7,8 and 9. Results showed both water and water-alcohol extractions had similar effects with a very low anaesthetic effect even at concentration of 2000 ppm. However, clove oil essence anaesthetized fish at a concentration below 100 ppm. The best anaesthetic effect and recovery time was found at concentration of 250 ppm at water temperature of 5°C and pH7. Considering the required times to anaesthetize and recovery the most suitable anaesthetic concentrations for fish at water temperature of 5°C were as follows:

* Fish less than I g body weight ** Fish of 1-10 g body weight