da Paz Clarissa Araújo, de Oliveira Suzane Maia, Hamoy Maria Klara Otake, Dos Santos Murilo Farias, do Amaral Anthony Lucas Gurgel, Barbosa Anara de Sousa, Eiró-Quirino Luciana, Paixão Daércio José de Macedo Ribeiro, Barbas Luis André Luz, Lopes Dielly Catrina Favacho, Torres Marcelo Ferreira, Hamoy Moisés
Laboratory of Pharmacology and Toxicology of Natural Products, Biological Sciences Institute, Federal University of Pará (UFPA), UFPA Campus Belém, Rua Augusto Corrêa No 01 Guamá, Belém, PA, CEP: 66075 - 110, Brazil.
Tropical Species Aquaculture Laboratory (LAET), Federal Institute of Education, Science, and Technology of Para (IFPA), Castanhal, PA, Brazil.
Sci Rep. 2025 Jan 30;15(1):3846. doi: 10.1038/s41598-025-88042-z.
The present study aimed to characterize the behavior and evaluate the electromyographic (EMG), electrocardiographic (ECG), and respiratory responses of Nile tilapia (Oreochromis niloticus) when exposed to different concentrations of Camphor (CPR) as a potential anaesthetic in immersion and recovery baths. The goal was to determine the impact of CPR on muscle, cardiac, and respiratory functions, and assess its suitability as an anesthetic for tilapia. Therefore, juvenile fish (38.2 ± 5.5 g) were acclimatized in aquaria for 20 days under controlled environmental and water quality conditions. Four concentrations of CPR (150, 200, 250 and 300 mg L) were used in immersion baths to evaluate behavioral, EMG, ECG changes and recordings of opercular beats during the short-term treatment (5 min of exposure). The latency time for loss of the postural reflex was dependent on the CPR concentration. The EMG recordings demonstrated muscle activity during treatment and recovery. The ECG and opercular beat recordings demonstrated a decrease in heart and respiratory rates, with changes in the recorded tracings being more evident at higher concentrations. However, the use of a concentration of 300 mg L makes the cardiac and respiratory effects more evident, with changes in the tracing, which can harm the animal's hemodynamics. However, lower concentrations (150 mg L) showed tachycardia and opercular hypermotility, demonstrating changes not compatible with anesthesia. This article demonstrated that CPR in high concentrations can be harmful to the hemodynamics of tilapia, causing electrocardiographic and respiratory changes for a long period, even after recovery of muscular activity and postural reflex.
本研究旨在描述尼罗罗非鱼（Oreochromis niloticus）在浸入不同浓度的樟脑（CPR）以及在恢复浴中作为潜在麻醉剂时的行为，并评估其肌电图（EMG）、心电图（ECG）和呼吸反应。目的是确定CPR对肌肉、心脏和呼吸功能的影响，并评估其作为罗非鱼麻醉剂的适用性。因此，幼鱼（38.2±5.5克）在可控的环境和水质条件下在水族箱中适应20天。在浸入浴中使用四种浓度的CPR（150、200、250和300毫克/升）来评估短期处理（暴露5分钟）期间的行为、EMG、ECG变化以及鳃盖搏动记录。姿势反射丧失的潜伏时间取决于CPR浓度。EMG记录显示了处理和恢复过程中的肌肉活动。ECG和鳃盖搏动记录显示心率和呼吸频率降低，在较高浓度下记录曲线的变化更明显。然而，使用300毫克/升的浓度会使心脏和呼吸效应更明显，记录曲线发生变化，这可能会损害动物的血液动力学。然而，较低浓度（150毫克/升）显示心动过速和鳃盖运动亢进，表明出现了与麻醉不相符的变化。本文表明，高浓度的CPR可能对罗非鱼的血液动力学有害，即使在肌肉活动和姿势反射恢复后，也会导致心电图和呼吸长期变化。
