Use of Electric Fish-Handling Gloves for the Implantation of Coelomic Transmitters in Adult Brook Trout (Salvelinus fontinalis)
Centre québécois sur la santé des animaux sauvages/Canadian Wildlife Health Cooperative, Faculté de Médecine Vétérinaire, Université de Montréal, St. Hyacinthe, Quebec, Canada
Electro-immobilization involves the passage of a low-voltage electric current through the body of a fish to induce tonic immobility. Electric fish-handling gloves1 (EFHGs) have been developed to facilitate fish handling. Even though the use of such gloves has been suggested as a residue-free alternative to chemical immobilization in field procedures such as surgical implantation of transmitters, the impact of this method on fish welfare has not been properly assessed. We evaluated markers of stress and of muscle integrity in fish following the surgical implantation of intracelomic transmitters in brook trout immobilized with EFHGs, with and without local infiltration of lidocaine.2 Surgeries performed on fish anesthetized with buffered Tricaine-methanesulfonate3 or with 40 mg/L eugenol were used as comparisons. The increase in lactate and creatine kinase levels were higher in fish immobilized with EFHGs, suggesting higher levels of muscular damage. An increase in plasmatic cortisol concentrations were observed in all groups one-hour post-procedure, but this increase was higher in the EFHGs group. These results suggest that surgeries performed on brook trout immobilized with EFHGs are associated with a higher stress level compared to standard immersion anesthesia. The infiltration of lidocaine did not have a measurable effect on the parameters tested. Based on our observations, immersion anesthesia remains superior to EFHGs for surgical procedures in brook trout, as far as animal welfare goes. Even if this study failed to demonstrate an analgesic effect of lidocaine infiltration, local analgesia is still recommended when performing surgical procedures in fish solely immobilized with EFHGs.
1. Electric Fish Handling Gloves, Smith-Root, Vancouver, WA 98686, USA.
2. Lurocaine 2%, Vetoquinol, Lavaltrie, QC J5T 3S5, Canada. 6 mg/kg.
3. TMS (MS-222), Syndel, Nanaimo, BC V9S 4M9, Canada. 60 mg/L.
We wish to thank the Station piscicole de Baldwin and Smith-Root for their collaboration. This project was supported by a grant from the Fond du Centenaire and by a contract with the Ministère des Forêts, de la Faune et des Parcs.
* Presenting author