Abstract

Status of individual animals is often shown in pigmentation. For instance, stress responsiveness is associated with melanin-based pigmentation in vertebrates in general. This pattern is evident in Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss), with melanin-based spots indicating stress coping style. Arctic char (Salvelinus alpinus) differ from other salmonids in pigmentation but have an association between carotenoid-based pigmentation and stress coping style. These pigmentation differences could be used as a fast and simple tool for improving breeding programs. However, the procedure for photographing individuals is stressful. Therefore, we wanted to investigate if 3 common inhalation anesthetics could be used to reduce the stress involved in the procedure compared to a no-anesthetics group. Behavior was also monitored during the anesthetization. All 3 anesthetics (Aquacalm, Benzocaine, and MS-222) differed in pigmentation compared to the no-anesthetics group by having a higher number of spots. In the anesthetic treatments as well as the no-anesthetics group, the fish had elevated plasma cortisol levels. In fact, the no-anesthetics group had higher cortisol than treated fish. This was probably because of procedural differences such as time affecting the stress response. Furthermore, in a long-term experiment, all fish survived and had similar condition factors 1 week after photographing as before. Therefore, the method for photographing Arctic char is deemed safe and could be used as a tool for estimating stress coping style, but careful planning is needed for experiments using it

Keywords

anesthetics; animal welfare; Arctic char; carotenoid pigmentation; stress

Published in

Journal of Veterinary Behavior: Clinical Applications and Research
2015, Volume: 10, number: 2, pages: 179-184

SLU Authors

• Backström, Tobias

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Heynen, Martina

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Brännäs, Eva

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Nilsson, Jan

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

• Magnhagen, Carin

  • Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Fish and Aquacultural Science
Ecology


Publication identifier

DOI: https://doi.org/10.1016/j.jveb.2014.11.007

Permanent link to this page (URI)

https://res.slu.se/id/publ/65405