The metabolic cost of subcutaneous and abdominal rewarming in king penguins after long-term immersion in cold water
| Autor: | Batshéva Bonnet, Andreas Nord, Agnès Lewden |
|---|---|
| Přispěvatelé: | Institut Pluridisciplinaire Hubert Curien (IPHC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
0106 biological sciences
Physiology 030310 physiology [SDV]Life Sciences [q-bio] Abdominal Fat Subcutaneous Fat 010603 evolutionary biology 01 natural sciences Biochemistry 03 medical and health sciences Animal science Blubber Immersion Medicine Heterothermy Animals 0303 health sciences biology business.industry Thermoregulation Feathers biology.organism_classification Aptenodytes patagonicus Metabolic cost Spheniscidae Cold Temperature Basal metabolic rate Metabolic rate Basal Metabolism General Agricultural and Biological Sciences Splanchnic business Developmental Biology Body Temperature Regulation |
| Zdroj: | Journal of Thermal Biology Journal of Thermal Biology, Elsevier, 2020, 91, pp.102638-. ⟨10.1016/j.jtherbio.2020.102638⟩ |
| ISSN: | 0306-4565 |
| DOI: | 10.1016/j.jtherbio.2020.102638⟩ |
| Popis: | Marine endotherms in the polar regions face a formidable thermal challenge when swimming in cold water. Hence, they use morphological (fat, blubber) adjustment and peripheral vasoconstriction to reduce demands for heat production in water. The animals then regain normothermia when resting ashore. In the king penguin (Aptenodytes patagonicus) metabolic rate is lower in fed than in fasted individuals during subsequent rewarming on land. This has been suggested to be a consequence of diversion of blood flow to the splanchnic region in fed birds, which reduces peripheral temperatures. However, peripheral temperatures during recovery have never been investigated in birds with different nutritional status. The aim of this study was, therefore, to measure subcutaneous and abdominal temperatures during the rewarming phase on land in fasted and fed king penguins, and investigate to which extent any different rewarming were reflected in recovery metabolic rate (MRR) after long term immersion in cold water. We hypothesized that fed individuals would have a slower increase of subcutaneous temperatures compared to fasted penguins, and a correspondingly lower MRR. Subcutaneous tissues reached normothermia after 24.15 (back) and 21.36 min (flank), which was twice as fast as in the abdomen (46.82 min). However, recovery time was not affected by nutritional condition. MRR during global rewarming (4.56 ± 0.42 W kg−1) was twice as high as resting metabolic rate (RMR; 2.16 ± 0.59 W kg−1). However, MRR was not dependent on feeding status and was significantly elevated above RMR only until subcutaneous temperature had recovered. Contrary to our prediction, fed individuals did not reduce the subcutaneous circulation compared to fasted penguins and did not show any changes in MRR during subsequent recovery. It seems likely that lower metabolic rate in fed king penguins on land reported in other studies might not have been caused primarily by increased circulation to the visceral organs. |
| Databáze: | OpenAIRE |
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