Anestesia de juvenis de curimba (Prochilodus lineatus, (Valenciennes, 1836): efeito da temperatura e anestésicos.

Abstract

The intensification of fish production in Brazil has driven research aimed at reducing stress in animals farmed. In this scenario, the use of anesthetics in handling procedures, such as: biometric, markers application, breeding selection and others, contribute to the maintenance of farmed fish well-being. This study represent more one improvement in Brazilian aquaculture by addressing the use of anesthetics in handling procedures of curimba Prochilodus lineatus. The aim of this study was to evaluate the effect of temperature and benzocaine, menthol and eugenol anesthetics, in curimba juvenile. The work was developed in the Pisciculture Didactic Unit, belonging to the Fisheries Institute Foundation of Rio de Janeiro State. The work is written in two capters. Chapter I adressed benzocaine anesthetic efficiency in curimba juvenile keeped at temperatures of 22, 25, 28 and 31°C. Chapter II reported the use of natural anesthetics (menthol and eugenol) for the specie anesthesia. The result showed that benzocaine is an efficient anesthetic to be used in curimba juveniles. The temperature has a direct effect on the induction time and recovery of juvenile species, while higher temperatures lead to a rapid induction and recovery. For deep anesthesia it is recommended that the concentration of 50 mg of benzocaine L-1 at temperatures of 25, 28 and 31°C and 60 mg L-1 at temperature of 22°C. The surgical anesthesia can be performed with the concentration of 50 mg L-1 at four temperatures. Regarding natural anesthetics, menthol and eugenol were effective to induce curimba juveniles to deep anesthesia stage and can be used for management practices in fish farming. The indicated menthol and eugenol concentrations for anesthesia of curimba juveniles, with an average weight of 7 g, are 60 and 50 mg L-1 respectively.