Triagem de óleos essenciais de plantas nativas para o desenvolvimento de novos sedativos e anestésicos para peixes

Abstract

Essential oils and their major constituents are now used in animals, mainly for the development of new drugs for veterinary use. Furthermore, the sedative and anesthetic actions of various oils are proven in the most varied procedures performed in animal production. However, there is a need for further studies aiming to characterize their sedative and anesthetic properties in fish. Among the challenges found in fish farming, one of them that deserves to be highlighted is the stress caused when handling biometrics, transport, surgical procedures, among others. This affects animal welfare and causes economic losses to production. So, natural agents are a possibility to minimize stress through anesthesia, as they cause minimal impacts to the environment and some have a good central depressant effect on fish, without causing major adverse effects. Thus, the chemical composition of essential oils was verified by gas chromatography. Furthermore, anesthetic induction and recovery experiments were carried out, also with long exposure to different essential oils, using jundiá juveniles (Rhamdia quelen) to determine effective concentrations for induction and recovery from anesthesia, as well as observation of possible adverse effects and mortality. The results indicated that the essential oils suitable for sedation are those from leaves of Pilocarpus pennatifolius, Cordia verbenacea, Casearia sylvestris, Prunus myrtifolia, Acmella oleracea and Aloysia hatschbachii; in addition to these, the oils from the inflorescences of Prunus myrtifolia and Acmella oleracea are also suitable for sedation. For anesthesia, essential oils from leaves of Prunus myrtifolia, Aloysia hatschbachii, Acmella oleracea, as well as A. oleracea flowers are indicated.