The Efficacy of Clove Seed Aqueous Extract as an Anesthetic Agent on the Stress Response of Mystus cavasius During Transportation

Mystus cavasius (locally known as Gulsha) is a commercially important catfish in Bangladesh, typically transported live in oxygenated polythene bags without anesthetics, often resulting in severe stress, injuries, and high mortality. This study evaluated the efficacy of clove seed aqueous extract (CAE) as a natural anesthetic at different concentrations to establish a standardized anesthetic protocol for minimizing transport‐related stress. Fish (15.14 ± 1.75 cm; 24.80 ± 1.50 g) were exposed to CAE across three experimental phases: (1) determination of effective concentrations (30–100 mg/L) based on induction and recovery times; (2) evaluation of opercular rate, water quality, and physiological stress indicators in oxygenated bags; (3) assessment of stress responses under varying packing densities using the optimal concentration. Results indicated that sedation was initiated between 40–55 mg/L CAE, with 55 mg/L identified as the most effective concentration for 9–12 h of transport. At this concentration, fish exhibited significantly reduced total ammonia nitrogen (TAN), blood glucose, and leukocyte counts, while maintaining 100% survival and minimal stress even under high‐density conditions. These findings demonstrate that CAE is an effective, natural, and locally available anesthetic for M. cavasius , leaving no harmful residues and ensuring safe and high‐quality live fish for consumers.