Evaluation of electronarcosis and clove oil for short-term anesthesia in common carp, Cyprinus carpio L. 1758

Anesthesia is considered to be the best way to ensure animal welfare during handling, manipulation, etc. Clove oil and electronarcosis are among the most popular chemical and physical anesthetics used in fisheries and biology. However there is a little information available on the effect of anesthesia using direct electric current in fish. In the present study, the impacts of clove oil (30 mg.l^-1) and electro-anesthesia (constant direct current, 0.5 v.cm^-1) (DC) were assessed in common carp, Cyprinus carpio during narcotic stage in two experimental sets. Experiment 1 was conducted to quantitatively compare induction of anesthesia and recovery time. The biochemical and hematological effects of anesthetics were analyzed as experiment 2. The results revealed that induction and recovery times in fish anesthetized with electric current were significantly lower than clove oil treatment. Significant differences were observed in cortisol concentrations, red blood cells and mean corpuscular hemoglobin concentration between anesthetic methods. Our results suggest that constant direct current electronarcosis induces anesthesia more quickly than clove oil, with lower side effects in common carp.