Use of Clove, Mint and Camphor Essential Oils on Confinement of Clown Anemonefish Amphiprion ocellaris (Cuvier 1830): Anesthetic Effects and Influence on Water Quality

Abstract

The aim of this study was to evaluate the anesthetic efficacy of essential oils of clove, mint and camphor to clownfish Amphiprion ocellaris and their effects on water quality in simulated confinement transport conditions. Anesthetic effects of clove, mint and camphor oils were tested at concentrations of 2.5, 5.0 and 7.5 μL L-1; 20, 25 and 30 μL L-1; and 100, 120 and 140 μL L-1, respectively. Confinement periods of 6 h, 12 h and 24 h were simulated (n=8 fish/time/concentration). Animals were randomly selected and transferred to polyethylene bags (16 × 30 cm, 5 fish L-1). Water concentrations of dissolved oxygen (DO), nitrogen in the form of total ammonium (N-TA=NH3+NH4 +) and non-ionized ammonia (N-NH3) and pH were measured before closing and after opening the bags. Different confinement densities of A. ocellaris (5, 10, 15 and 20 fish L-1) were tested in polyethylene bags containing water and anesthetics essential oils. Concentrations of 5, 25 and 120 μL L-1 (clove, mint and, camphor oils, respectively) were used during 24 h of confinement. Water-quality parameters monitored were the same as in the previous experiment, with addition of measuring concentrations of dissolved CO2 in water. The use of mint oil (25 μL L-1, maximum density of 10 fish L-1) significantly reduced the concentration of N-TA. At low densities (5 fish L-1) clove (5 μL L-1) and camphor (120 μL L-1) oils can also be safely used for confinement of Amphiprion ocellaris for 24 h.