Effects of capture stress on free-ranging, reproductively active male Weddell seals
journal contribution
posted on 2023-05-17, 03:01authored byHarcourt, RG, Turner, E, Hall, A, Waas, JR, Mark HindellMark Hindell
Abstract Physiological stress responses to capture may be an indicator of welfare challenges induced by animal handling. Simultaneously, blood chemistry changes induced by stress responses may confound experimental design by interacting with the biological parameters being measured. Cortisol elevation is a common indicator of stress responses in mammals and reproductive condition can profoundly influence endocrine response. We mea- sured changes in blood cortisol and testosterone induced by handling reproductively active male Weddell seals (Lep- tonychotes weddellii) early and late in the breeding season. Weddell seals have the highest resting cortisol levels of all mammals yet showed a clear, prolonged elevation in cor- tisol in response to capture. Responses were similar when first caught and when caught a second time, later in the breeding season. Baseline testosterone levels declined over the breeding season but were not altered by capture. Administering a light dose of diazepam significantly ameliorated the cortisol response of handled animals without affecting testosterone levels. This may be an effective way of reducing acute capture stress responses. Male breeding success in years males were handled was no different to the years they were not, despite the acute capture response, suggesting no long-term impact of han- dling on male reproductive output.
History
Publication title
Journal of Comparative Physiology A: sensory, neural, and behavioral physiology
Volume
196
Pagination
147-154
ISSN
0340-7594
Department/School
School of Natural Sciences
Publisher
Springer-Verlag
Place of publication
175 Fifth Ave, New York, USA, Ny, 10010
Rights statement
The original publication is available at www.springerlink.com
Repository Status
Restricted
Socio-economic Objectives
Assessment and management of coastal and estuarine ecosystems