anaesthetic effect of camphor (Cinnamomum camphora), clove (Syzygium aromaticum) and mint (Mentha arvensis) essential oils on clown anemonefish, Amphiprion ocellaris (Cuvier 1830)

The aim of this study was to evaluate the use of clove (Syzygium aromaticum), camphor (Cinnamomum camphora) and mint (Mentha arvensis) essential oils as anaesthetics during the management of clown anemonefish (Amphiprion ocellaris). For 15 min, the animals were subjected to concentrations of 5, 10, 20, 27 and 35 μL L⁻¹ of clove oil, 17, 35, 50, 70 and 100 μL L⁻¹ of mint oil, and 200, 400, 500, 550 and 600 μL L⁻¹ of camphor oil (tested in 10 animals per concentration). A control group (without anaesthetic) and a complementary group, which was exposed to ethanol, were also evaluated. After exposure to the anaesthetic, the fish were transferred to clean water to assess recovery. The mortality and feeding behaviour of the fish were then observed for 48 h after exposure to the oils. All of the essential oils produced an anaesthetic effect on A. ocellaris. The 27, 70 and 500 μL L⁻¹ concentrations of clove, mint, and camphor oils promoted surgical anaesthesia after 310.5, 312.0, and 535.0 s (medians) respectively. The recovery times of fish exposed to these same concentrations were 396, 329.5 and 229 s respectively. The decision of which oil to use is dependent on the management situation and the consideration of the induction and recovery times of each essential oil.