Evaluation of Anesthesia Protocols for Handling Hogfish Using Tricaine Methanesulfonate and AQUI‐S 20E

Abstract

AbstractThe Hogfish Lachnolaimus maximus is a high‐value food fish with significant recreational and commercial fishing pressure and is a candidate species for marine aquaculture. There is a need to define safe and effective methods of anesthesia for handling of this species for aquaculture. Anesthesia efficacy was assessed with wild‐collected adult (>20 cm; 0.2–1.2 kg) and juvenile F1 (<11 cm; 5–50 g) Hogfish by using tricaine methanesulfonate (Tricaine‐S) at 25, 50, 100, 125, and 150 mg/L and AQUI‐S 20E (10% eugenol) at 50, 75, 100, 200, 300, 400, and 500 mg/L to determine favorable doses for minor handling. Favorable doses resulted in induction of light anesthesia and recovery times each under 5 min, zero mortality, and limited excitation behavior. For adult Hogfish, Tricaine‐S was effective at inducing light anesthesia at 100–150 mg/L and was preferred over the effective range of AQUI‐S 20E doses (100–200 mg/L) based on fish behavioral observations while undergoing anesthesia. Additionally, induction of deep anesthesia was explored to inform potential doses for major and potentially lethal procedures. These same ranges were effective at inducing deep anesthesia in adults. Juvenile fish were effectively anesthetized at the same doses of Tricaine‐S (100–150 mg/L) and were induced to light and deep anesthesia faster than adults at the same dose levels. AQUI‐S 20E was effective at inducing light anesthesia in juveniles at all levels tested; however, no favorable dose for deep anesthesia was found. Overall, Hogfish were anesthetized with Tricaine‐S at similar doses used with other species and responded to AQUI‐S 20E similarly in terms of efficacy but unfavorably in terms of behavior.