The use of clove oil as an anesthetic for advanced juvenile tilapia

• Published in: Acta scientiarum. Animal sciences 2012-04, Vol.34 (2), p.175
• Main Authors: Simoes, Larissa Novaes, Gomide, Andrea Tassis Mendonca, Almeida-Val, Vera Maria Fonseca, Val, Adalberto Luis, Gomes, Levy Carvalho
• Format: Article
• Language: Spanish
• Subjects: Anesthesia; Aquaculture industry; Blood glucose; Central nervous system agents; Evaluation; Glucocorticoids; Hemoglobins; Mariculture; Physiological aspects
• ISSN: 1806-2636
• DOI: 10.4025/actascianimsci.v34i2.13022

Handling of live fish is inevitable in fish farms and causes a number of adverse physiological reactions, thus requiring the use of anesthetics. The main goal of the present work was to evaluate the efficiency of clove oil as an anesthetic for juvenile tilapia (approximately 55 g and 13 cm) during handling. In the first experiment, fishes were exposed to an anesthetic bath at six concentrations (80, 100, 150, 200, 250 and 300 mg [L.sup.-1]). Subsequently, the induction time was assessed for different stages of anesthesia. In the second experiment, different times of exposure to anesthesia were tested, aiming to assess the safety margin of the anesthetic. Finally, we evaluated the responses to stress after exposure to 250 mg [L.sup.-1] anesthesia. The following parameters were tested: cortisol, glucose, hematocrit, hemoglobin, and plasma sodium and potassium levels. The concentration of 250 mg [L.sup.-1] of clove oil is the most appropriate to induce surgical anesthesia, and 150 mg [L.sup.-1] for biometrics and brief handling. Anesthesia at the ideal concentration for 10 minutes did not result in severe stress. Only blood glucose and hematocrit were affected after anesthesia. Keywords: stress, eugenol, handling, sedation. A inevitavel manipulacao de peixes vivos em piscicultura causa uma serie de reacoes fisiologicas adversas, o que exige o uso de anestesicos. O objetivo foi avaliar a eficiencia do oleo de cravo como anestesico para juvenis avancados (aproximadamente 55g e 13 cm) de tilapia do Nilo durante o manejo. No primeiro experimento, os peixes foram expostos a banhos anestesicos em seis diferentes concentracoes (80; 100; 150; 200; 250 e 300 mg [L.sup.-1]) e foi avaliado o tempo de inducao aos diferentes estagios de anestesia. No segundo experimento, avaliaram-se os diferentes tempos de exposicao a anestesia, sendo verificada a margem de seguranca do anestesico. Por ultimo, avaliaram-se as respostas de estresse apos a anestesia em 250 mg [L.sup.-1]. Os parametros avaliados foram cortisol, glicose, hematocrito, hemoglobina e niveis plasmaticos de sodio e potassio. A concentracao 250 mg [L.sup.-1] de oleo de cravo foi a mais adequada para inducao de anestesia cirurgica. Para a anestesia voltada para biometria e breve manejo, a concentracao mais adequada foi 150 mg [L.sup.-1]. A exposicao a concentracao ideal de oleo de cravo por 10 min., nao causou estresse severo, ocorrendo alteracoes apos a anestesia somente nos niveis de glicose e hematocrito. Palavr