Anesthetic effect and acute toxicity of Citrus sinensis essential oil in betta

Abstract

This study investigated the use of Citrus sinensis essential oil (EOCS) in Betta splendens, evaluating toxicity, induction and recovery times to anesthesia, its action on agonist behavior, and on male collective transport. To toxicity, fish were exposed to EOCS at different concentrations during 48 h. The induction test was performed to evaluate sedation, anesthesia, and recovery under different concentrations. To assess agonist behavior, male subjects were maintained with different dosages of EOCS, assessing opercular beat and fin expansion, while exposed to untreated animals. In the mass transport study, males were divided into two treatments with two levels of EOCS, for 6 h, also analyzing gill histometry at the end of transport. The results obtained show that the mean lethal concentration in 48 h of exposure to EOCS was calculated at 49.17 μL·L−1. The shortest anesthesia induction time was at 300 μL·L−1 EOCS. EOCS was able to reduce agonist behavior in males individual. Histometric analyzes revealed a reduction in the height of gill filaments in fish transported with 20 μL·L-1 EOCS. EOCS can be used as a sedative and anesthetic agent for B. splendens.