Analysis of changes in coral trout (Plectropomus leopardus) morphology and tissue after exposure to clove oil

Abstract

Clove oil has been shown to be effective as an alternative to cyanide in the catching of groupers on coral reefs. However, it is necessary to analyze the quality of fish after exposure prior to application in the field. The aim of this study was to analyze changes in morphology and tissues of the eyes, gills and liver of coral trout (Plectropomus leopardus) after exposure to clove oil. Experiments were conducted in an aquarium measuring 1.0 mx 0.5 m x 1.0 m filled with seawater. The fish were sprayed with several concentrations of clove oil (20, 30, 40, 50, 60 ppm) until stunned, then transferred into the tank for observation of external morphology and fish tissue. The results showed that exposure to clove oil at concentrations of 20-60 ppm had no effect on coral trout external morphology (eyes, skin, scales, fins and gill covers). Histologically, small changes were observed in the eye, gill and liver tissues starting at a concentration of 30 ppm. This study showed that exposure to clove oil at a concentrations of 20 ppm did not appear to have harmful effects on coral trout (Plectropomus leopardus).