Dear Lucille,

There are some studies conducted on fish as well as animals:

Mice:

Pharmacology. 1976;14(4):367-77.

Anesthetic action of methyleugenol and other eugenol derivatives.

Sell AB, Carlini EA.

Abstract

A comparative study of four natural eugenol compounds found in the volatile oil fraction of Myristica fragans, namely eugenol (E), methyleugenol (ME), isoeugenol and methylisoeugenol, was carried out in mice. Using a mixture of saline + tween-80 to suspend the compounds and the intraperitoneal route, ME revealed to be the most active and the less toxic in inducing the loss of the righting reflex. ME was further compared with pentobarbital and with the synthetic E derivative, propanidid, using the intraperitoneal route in rats. ME anesthetized the rats more rapidly than pentobarbital; however, the duration of anesthesia was the same for both drugs. Propanidid was not active when injected through the intraperitoneal route. Rats under ME anesthesia could be more easily operated, showed less cyanosis, and recovered better than those under pentobarbital. When injected intravenously in rabbits, ME and propanidid showed equivalent anesthetic effects. Daily intraperitoneal injections of ME in rats and mice for up to 42 days, showed that the drug was not toxic and that the animals became more sensitive to the anesthetic action with repeating the injections. Similarly to pentobarbital, ME induced large amounts of slow wave activity in EEG of rats and did not change the total brain levels of dopamine, norepinephrine, and 5-hydroxytryptamine.

http://www.ncbi.nlm.nih.gov/pubmed/935250

Fish:

An. Acad. Bras. Ciênc. vol.87 no.1 Rio de Janeiro Mar. 2015

http://dx.doi.org/10.1590/0001-3765201520140024 

AGRARIAN SCIENCES

Efficiency of eugenol as anesthetic for the early life stages of Nile tilapia (Oreochromis niloticus)

Paula A.P. Ribeiro1  , Kleber C. Miranda-Filho1  , Daniela C. de Melo1  , Ronald K. Luz1 

 ABSTRACT

In aquaculture, activities with anesthetic compounds are usually used in order to ensure the welfare of farmed fish, allowing handling out of water with decreased trauma by stress. Presently, there is no information about anesthetic action of eugenol in early life stages of Nile tilapia (Oreochromis niloticus). The objective of this study was to evaluate different concentrations of eugenol for larvae and juveniles of Nile tilapia. Sixty animals were used for each group of weight, group I = 0.02 g; group II = 0.08 g; group III = 0.22 g; group IV = 2.62 g; and group V = 11.64 g. The eugenol concentrations tested were 50, 75, 100, 125, 150 and 175 mg L-1. No mortality was reported during the tests with eugenol. Tilapia larvae with 0.02 g and juveniles around 11.64 g can be anesthetized with eugenol concentrations between 150 and 175 mg L-1, since they determine the shortest sedation time (23 and 72 seconds, for the group of lowest and highest weights, respectively).

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000100529

Cienc. Rural vol.40 no.10 Santa Maria Oct. 2010  Epub Oct 01, 2010

http://dx.doi.org/10.1590/S0103-84782010005000154 

PAPERS

BIOLOGY

Anesthesia of silver catfish with eugenol: time of induction, cortisol response and sensory analysis of fillet

ABSTRACT

The aim of this study was to identify the time of anesthetic induction and recovery of silver catfish (Rhamdia quelen) exposed to eugenol. It was also determined the efficacy of the anesthetic as a stress reducing agent and performed a sensory analysis of the fillets from fish exposed to this substance. The silver catfish were exposed to air for 1min to carry out biometry, and blood was collected at 0, 1 and 4 hours later. Eugenol can be used in the range of 20-50mg L-1 for anesthetic induction in silver catfish, and recovery time from anesthesia was not affected by eugenol concentration. The control group showed significantly higher cortisol levels 4 hours after biometry than at time zero. Fish anesthetized with eugenol (50mg L-1) presented significantly lower plasma cortisol levels than control fish at the same time. These data indicate that eugenol inhibits the rise of cortisol in the blood. The sensory analysis test demonstrated that eugenol modifies the flavor of the fillet and therefore is contra-indicated for anesthetization of silver catfish that are intended for human consumption.

http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782010001000009

Clinical Anesthesia and Analgesia in Fish

Lynne U. Sneddon

University of Liverpool

ABSTRACT

Fish have become a popular experimental model and companion animal, and are also farmed and caught for food. Thus, surgical and invasive procedures in this animal group are common, and this review will focus on the anesthesia and analgesia of fish. A variety of anesthetic agents are commonly applied to fish

via immersion. Correct dosing can result in effective anesthesia for acute procedures as well as loss of consciousness for surgical interventions. Dose and anesthetic agent vary between species of fish and are further confounded by a variety of physiological parameters (e.g., body weight, physiological stress) as

well as environmental conditions (e.g., water temperature). Combination anesthesia, where 2 anesthetic agents are used, has been effective for fish but is not routinely used because of a lack of experimental validation. Analgesia is a relatively underexplored issue in regards to fish medicine. However, recent

studies have investigated opioid agents, nonsteroidal anti-inflammatory drugs, and local anesthetics to determine their efficacy in minimizing pain and discomfort. The opioid morphine and the local anesthetic lidocaine do have significant effectiveness in reducing pain-related responses in rainbow trout (Oncorhynchus mykiss). Studies aimed at developing reliable analgesic protocols should explore a wide

range of analgesic drug classes in several fish species.

http://animalstudiesrepository.org/cgi/viewcontent.cgi?article=1032&context=acwp_vsm

Hoping this will be helpful,

Rafik

Dear Lucille,

Refik has given you some good references, particularly the last one.   As you will see in that paper , the response of different fish species to different anesthetic agents varies widely.

I have only done a little in vivo electrophysiology (mapping visual field responses), but I have done this in two different types of fish (goldfish and zebrafish).  What I can tell you is that if you plan to use artificial ventilation with a mouth tube to maintain animal viability and good neuronal function (similar to Figure 6 in the last reference), you need to find a drug that has a dose and kinetics that is compatible with that delivery method.

I believe many investigators use MS-222.  It has been around a long time, so you have a baseline with which to find the correct dosage.  Also, although the method of action isn't totally understood, I believe it acts mostly on sodium channels.  I have never used eugenol, but the neuropharmacological profile suggests that it acts on many different aspects of brain function.  It would not be suitable for the studies done in the lab in which I work, but I don't know what studies you have planned.  

Whatever you decide to try, you should also consult with your campus Veterinarian. 

Good Luck!

Jill

Hi, the attached link will provide a paper published in 2008 by my group, showing that isoeugenol activates the TRPA1 ion channel expressed in human and rat sensory nerves.  This ion channel is involved in nociception or pain signalling.

http://www.sciencedirect.com/science/article/pii/S0304394008004679