Efficiency of clove oil as anesthetic for abalone (Haliotis Tuberculata Coccinea, Revee)

Abstract

The efficacy of clove oil as an anesthetic was evaluated in adult Haliotis tuberculata coccinea (shell length, 42-80 mm) and was compared with the commonly used 2-phemoxyethanol. The clove oil was previously mixed at 50% with absolute ethanol, and 4 different concentrations were tested: 0.1, 0.3, 0.5, and 0.7 mL/L. The trial was replicated 3 times. Relaxation and recovery time, muscle condition, and mortality after 1 wk were considered to evaluate the efficiency of anesthetics. The results showed that clove oil at 0.5 mL/L was the lowest concentration that removed all abalone from the rearing helters in 8.9 +/- 3.5 min, showing 2 +/- 1.5 min of recovery time. Although clove oil is appropriate for handling animals, it was not suitable for pearl culture because it left the abalone muscle hard, making access to the pearl nuclei insertion site difficult. In comparison with 2-phenoxyethanol, clove oil was effective in 10-fold lower doses.