Anaesthetic and antioxidant effects ofMyrcia sylvatica(G. Mey.)DC. andCurcuma longaL. essential oils on tambaqui (Colossoma macropomum)

Abstract

Anaesthetic substances are necessary to reduce fish stress during aquaculture activities. The objectives of this study were: (i) to determine the efficacy of essential oils (EOs) of Myrcia sylvatica (EOMS) and Curcuma longa (EOCL) as anaesthetics for Colossoma macropomum and (ii) to evaluate the effects of rapid anaesthesia and long-term sedation (6 h) with these oils. Therefore, the main primary stress indicator (cortisol) and secondary factors (biochemical indices, hepatic metabolism, oxidative biomarkers) were measured. Sedation with the EOCL resulted in lower cortisol levels compared to control group. Total cholesterol levels were lower in fish sedated with EOMS than in control. Lactate levels were higher in fish anaesthetized with both EOs and sedated with EOCL compared to control. Both EOs increased hepatic glycogen levels after anaesthesia and EOMS increased this parameter after sedation compared to control. Anaesthesia and sedation with EOs resulted in lower levels of lipid peroxidation (LPO) compared to control. In turn, the activity of some antioxidant enzymes evaluated (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase), the content of non-protein thiols and total reactive antioxidant potential were higher in tissues of fish anaesthetized and sedated with EOs compared to control. This induction of antioxidant capacity in the tissues could be due to the antioxidant property exerted by these EOs. Thus, EOMS and EOCL are recommended for anaesthesia and sedation of fish because in spite of inducing anaerobic metabolism, these EOs did not alter most biochemical parameters, reduced the LPO and increased the antioxidant capacity in vital tissues.

Myrcia sylvatica essential oil in the diet of gilthead sea bream (Sparus aurata L.) attenuates the stress response induced by high stocking density

“…Similar results were found in R. quelen and Paralichthys olivaceus fed with diets containing rutin (Pês, Saccol, Ourique, Londero, Gressler, Finamor et al., ) and quercetin (Shin, Yoo, Min, Lee, & Choi, ), respectively, both compounds considered as important antioxidants. Regarding the effects of EOs, several studies have shown that these substances act as anaesthetics and prevent an increase in plasma cortisol levels in different fish species, supposedly blocking sensorial transmission to the hypothalamus, as well as the subsequent triggering of the hormonal cascade (Gressler et al., ; Iversen, Finstad, McKinley, & Eliassen, ; Saccol, Londero et al., ; Saccol, Toni et al., ). However, the exact mechanism underlying the effect of EOs on cortisol secretion remains unknown.…”

“…These results are similar to those found in previous studies on this plant. In the study of Saccol, Toni et al (2017), the major components of the EOMS were β-selinene (9.96%), cadalene (9.36%), α-calacorene (9.17%) and Z-calamene (8.17%), whereas Silva et al (2016) they found these and others components at higher percentages, such as 1-epi-cubenol (9.9%), cadalene (7.2%), β-selinene (7.0%),…”

“…This species is known as “murta” in the Amazon region and is frequently used in popular medicine (Zoghbi, Andrade, Silva, Carreira, & Maia, ). Previous studies demonstrated that the EO of this species (EOMS) has anaesthetic and sedative effects in matrinxã ( Brycon amazonicus ) (Saccol, Londero et al., ) and tambaqui ( Colossoma macropomum ) (Saccol, Toni et al., ), associated with stress reduction as a consequence of decreased cortisol levels. Silva et al.…”

“…Previous studies demonstrated that the EO of this species (EOMS) has anaesthetic and sedative effects in matrinxã (Brycon amazonicus) (Saccol, Londero et al, 2017) and tambaqui (Colossoma macropomum) (Saccol, Toni et al, 2017), associated with stress reduction as a consequence of decreased cortisol levels. Silva et al (2016) concluded that EOMS could be used in pharmaceutical formulations to control resistant bacterial strains or to prevent food spoilage, individually or in combination with traditional antibiotic products.…”

The use of feed and water additives for live fish transport

“…The use of plant essential oils as dietary supplements in aquaculture was recently reviewed (Sutili et al 2017) but to our knowledge, only two studies have considered the effects of plant extracts on stress tolerance during transportation through administration as a dietary supplement. Turmeric (Curcuma longa, Linnaeus 1758) has a variety of documented medicinal properties (anti-inflammatory, Ara ujo & Leon 2001;immunostimulant, Chattopadhyay et al 2004;antioxidant, Luthra et al 2001;Saccol et al 2016;anaesthetic, Saccol et al 2016;antimicrobial, Luthra et al 2001;antiparasitic, Ara ujo & Leon 2001). Supplementing the diet of juvenile yellow tail tetra (Astyanax aff.…”