Óleo essencial de Aloysia triphylla é efetivo no transporte de tilápia do Nilo

Abstract

The study evaluated the use of the essential oil of Aloysia triphylla (EOAT) as stress reducer in transporting Nile tilapia, Oreochromis niloticus. Juveniles were transported for 8 h in plastic bags by car with water containing 0 (control), 20 or 30 μL L-1 EOAT (three replicates). We evaluated water quality, net ion fluxes (Cl−, Na+ and K+) and plasma parameters (cortisol, glucose, lactate and paraoxonase) and ventilatory rate (VR) of Nile tilapia. There was no mortality in juveniles undergoing transport. Nile tilapia transported with 20 or 30 μL L-1 EOAT presented lower pH than control group and with 30 μL L-1 EOAT presented lower water conductivity, alkalinity and Cl−, Na+ and K+ net ion fluxes compared to other treatments. The EOAT did not alter plasma cortisol and paraoxonase levels, but reduced VR, and 30 μL L-1 EOAT reduced plasma glucose levels compared to the control group after transport. The use of 20 μL L-1 EOAT increased plasma lactate levels compared to other treatments. The use of 30 μL L-1 EOAT for sedation in 8 h transport of Nile tilapia is recommended because it improved water quality and reduced ionic losses, plasma glucose levels and VR.

Essential oil of Ocimum basilicum and Eugenol as Sedatives for Nile Tilapia

“…According to Baldisserotto et al (2008), the pH decrease occurs due to a reduction in the excretion of non-ionized ammonia, which can justify the results of the present work, considering that the total ammonia nitrogen concentration was lower in the treatment with eugenol 20 µl L -1 . Similar results were obtained in the transport water of Nile tilapia with essential oil of A. triphylla at the concentrations of 20 or 30 μL L -1 (Teixeira et al, 2018). It is important to highlight that the values of pH obtained in all treatments were within the range (6 to 9) considered adequate for tropical fish (Boyd, 1998).…”

“…However, after 2, 3 and 4 h, the ventilatory frequency was significantly lower in all treatments with anesthetics when compared to the control group (Becker et al, 2012). Nevertheless, the essential oil of A. triphylla reduced the ventilatory frequency of Nile tilapia after 30 minutes of exposure (Teixeira et al, 2018). Therefore, it is possible to infer that de modulation of the ventilatory frequency is easily changed, making it difficult to establish a pattern for a general response.…”

“…Journal of Agricultural Studies ISSN 2166-0379 2020 out to evaluate the sedative effect and the ventilatory frequency in different fish species exposed to essential oils, obtaining positive results for the modulation of the ventilatory frequency in Nile tilapia O. niloticus with essential oil of L. alba (Hohlenwerger et al, 2017) and Aloysia triphylla (Teixeira et al, 2018). However, the species and size of fish, as well as the dose, composition, and relative abundance of certain compounds of the essential oil are factors that influence the ventilatory response.…”

Essential Oils as Stress-Reducing Agents for Fish Aquaculture: A Review

“…In addition, transport significantly decreased corticotrophin-releasing hormone ( crh ) and urotensin I ( ui ) expression levels in the brain of Coilia nasus and induced oxidative stress (Du et al, 2015). Furthermore, stress by transport induced an osmotic imbalance with ion loss in freshwater fish, showing a good correlation with transport stress (Becker et al, 2013, 2016; Parodi et al, 2014; Zeppenfeld et al, 2014; Garcia et al, 2015; Ostrensky et al, 2016; Teixeira et al, 2018; Table 2). Thus, during or prior to transport, sedation of the fish is desirable to reduce or prevent stress.…”

“…The use of this EO (40 and 50 μL⋅L –1 ) during a 6 h transport reduced net ion loss (Parodi et al, 2014), ammonia excretion and plasma cortisol levels in silver catfish compared to control fish submitted to the same procedure (Zeppenfeld et al, 2014). Plasma cortisol enhancement in fat snook due to transport was reduced by adding 20 μL⋅L –1 of this EO to the water (Parodi et al, 2016), whereas 30 μL⋅L –1 decreased ventilatory rate, ion loss and plasma glucose levels, with no effects preventing cortisol increase in Nile tilapia (Teixeira et al, 2018), both compared to their respective control fish subjected to the same procedure. In addition, this EO (25 μL⋅L –1 ) also decreased ventilatory rate of pacamã, Lophiosilurus alexandri , as well as ammonia excretion during 4 h transport (Becker et al, 2017; Table 2), also reducing the swimming activity of black piranha at concentration of 10 μL⋅L –1 (Almeida et al, 2018) both compared to their respective control fish subjected to the same procedure.…”