Skip to Main content Skip to Navigation
Journal articles

Lipid-induced thermogenesis is up-regulated by the first cold-water immersions in juvenile penguins

Abstract : The passage from shore to marine life is a critical step in the development of juvenile penguins and is characterized by a fuel selection towards lipid oxida- tion concomitant to an enhancement of lipid-induced ther- mogenesis. However, mechanisms of such thermogenic improvement at fledging remain undefined. We used two different groups of pre-fledging king penguins (Apteno- dytes patagonicus) to investigate the specific contribution of cold exposure during water immersion to lipid metabo- lism. Terrestrial penguins that had never been immersed in cold water were compared with experimentally cold-water immersed juveniles. Experimentally immersed penguins underwent ten successive immersions at approximately 9–10 °C for 5 h over 3 weeks. We evaluated adaptive ther- mogenesis by measuring body temperature, metabolic rate and shivering activity in fully immersed penguins exposed to water temperatures ranging from 12 to 29 °C. Both never-immersed and experimentally immersed penguins were able to maintain their homeothermy in cold water, exhibiting similar thermogenic activity. In vivo, perfusion of lipid emulsion at thermoneutrality induced a twofold larger calorigenic response in experimentally immersed than in never-immersed birds. In vitro, the respiratory rates and the oxidative phosphorylation efficiency of isolated muscle mitochondria were not improved with cold-water immersions. The present study shows that acclimation to cold water only partially reproduced the fuel selection towards lipid oxidation that characterizes penguin acclima- tization to marine life.
Document type :
Journal articles
Complete list of metadatas
Contributor : Nathalie Lyvet <>
Submitted on : Thursday, June 16, 2016 - 3:15:45 PM
Last modification on : Tuesday, March 17, 2020 - 2:36:21 AM




Loïc Teulier, Benjamin Rey, Jérémy Tornos, Marion Le Coadic, Pierre-Axel Monternier, et al.. Lipid-induced thermogenesis is up-regulated by the first cold-water immersions in juvenile penguins. Journal of Comparative Physiology B, Springer Verlag, 2016, 186, pp.639-650. ⟨10.1007/s00360-016-0975-3⟩. ⟨hal-01332835⟩



Record views