Anesthetic efficacy of tricaine methanesulfonate, metomidate and eugenol: Effects on plasma cortisol concentration and neutrophil function in fathead minnows (Pimephales promelas Rafinesque, 1820)

Abstract

Anesthetic efficacy, plasma cortisol concentration, and two parameters of neutrophil function (oxidative burst and degranulation of primary granules) were compared among three anesthetics in the fathead minnow: tricaine methanesulfonate (MS 222), metomidate hydrochloride (MTMD), and eugenol (EUG). The optimum anesthetic concentration was determined as: MS 222 75 mg L − 1 , EUG 30 mg L − 1 and MTMD 4 mg L − 1 . Handling and crowding stress was induced in fish with (SA) and without (S) anesthetic. Plasma cortisol concentration was measured at 0, 30, 90, and 240 min after stress and found to increase at 30 min post-stress in S and SA MS 222 groups, but not in SA MTMD and SA EUG groups. To test the effects of different anesthetics on neutrophil function, fish were divided into a baseline control group, a group exposed to handling and crowding stress (S) and a stressed anesthetized group (SA). Fish were assayed for neutrophil function before and after stress (24 h, 72 h and 7 days). The degranulation of neutrophil primary granules was measured as exocytosis of myeloperoxidase (MPO) using 3, 3′, 5, 5′-tetramethylbenzidine as a substrate. Degranulation of primary granules was decreased to 60-75% of non-stressed control in stressed and fish treated with MS 222, and was not affected when MTMD and EUG were used. The degranulation of primary granules proved to be a useful assay for measuring the effects of stress on neutrophil function in fish. Eugenol and metomidate prevented stress-induced decrease of neutrophil function while MS 222 did not. RightsWorks produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted. AbstractAnesthetic efficacy, plasma cortisol concentration, and two parameters of neutrophil function (oxidative burst and degranulation of primary granules) were compared among three anesthetics in the fathead minnow: tricaine methanesulfonate (MS 222), metomidate hydrochloride (MTMD), and eugenol (EUG). The optimum anesthetic concentration was determined as: MS 222 75 mg L − 1 , EUG 30 mg L − 1 and MTMD 4 mg L − 1 . Handling and crowding stress was induced in fish with (SA) and without (S) anesthetic. Plasma cortisol concentration was measured at 0, 30, 90, and 240 min after stress and found to increase at 30 min post-stress in S and SA MS 222 groups, but not in SA MTMD and SA EUG groups. To test the effects of different anesthetics on neutrophil function, fish were divided into a baseline control group, a group exposed to handling and crowding stress (S) and a stressed anesthetized group (SA). Fish were assayed for neutrophil function before and after stress (24 h, 72 h and 7 days). The degranulation of neutrophil primary granules was measured as exocytosis of myeloperoxidase (MPO) using 3, 3′, 5, 5′-tetramethylbenzidine as a substrate. Degranulation of primary granules was decreased to 60-75% of non-stressed control in stressed and fish treated with MS 222, and was not affected when MTMD and EUG w...

Hematological effects of etomidate and tricaine in common carp

“…Inhibition of the immunosuppressive effect of handling stress (lymphopenia, neutrophilia, and reduction of phagocyte oxidative metabolic activity) in carp juveniles sedated with etomidate was also observed in our previous study (18). Palic et al (30) reported that metomidate prevented stressinduced decrease of neutrophil function in Pimephales promelas, while MS-222 did not. Ortuno et al (21) found that tricaine did not suppress respiratory burst and other phagocyte functions in Sparus aurata.…”

Anesthetic use of eugenol and benzocaine in juveniles of red tilapia (Oreochromis sp.)

“…In the same study, higher plasma cortisol concentrations were found in benzocaine-exposed fish as compared to those exposed to eugenol (Iversen et al, 2003). In contrast to the present results, Palic et al (2006) reported no significant differences in plasma cortisol concentrations of fish anesthetized with MS-222, metomidate and eugenol (Palić et al,2006). In rainbow trout, no differences were observed in plasma cortisol levels between MS-222, eugenol, and CO 2 (Pirhonen et al, 2003).…”

Anesthesia and transport of fat snook Centropomus parallelus with the essential oil of Nectandra megapotamica(Spreng.) Mez

“…A variety of anesthetics such as tricaine methanesulphonate (MS-222), 2-phenoxyethanol, quinaldine, benzocaine, and metomidate have been used for this purpose (Ross & Ross, 2008). However, the use of some anesthetics has been limited or rejected due to undesirable side effects for fish and humans (Palic et al, 2006). Alternatively, several studies using plant derivative compounds, such as essential oils (EOs) from Eugenia, Mentha, and Lippia species, have demonstrated that these natural products are effective for fish sedation and may have benefits over traditional methods, including lower cost and higher safety (Cunha et al, 2010a;Gonçalves et al, 2008;Palic et al, 2006).…”