Metabolic adaptations of Muscovy duckling (Cairina moschata) and King penguin (Aptenodytes patagonicus) to chronic cold exposure

• Main Author: Teulier, Loïc
• Other Authors: Physiologie intégrative, cellulaire et moléculaire (PICM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard - Lyon I, Damien Roussel, Jean-Louis Rouanet
• Format: Doctoral or Postdoctoral Thesis
• Language: French
• Published: HAL CCSD 2010
• Subjects: Thermorgulation; King penguin; Birds; Metabolism; Indirect calorimetry; Aviar UCP; Cold; Ecophysiology; Oiseaux; Calorimétrie indirecte; Manchot royal; Métabolisme; Thermorégulation; UCP aviare; Froid; Ecophysiologie; [SDV.BA]Life Sciences [q-bio]/Animal biology; Arctic; Manchot; Antarc*; Antarctica; Antarctique*; Arctique*; King Penguins
• Online Access: https://theses.hal.science/tel-00799347; https://theses.hal.science/tel-00799347/document; https://theses.hal.science/tel-00799347/file/TH2010_Teulier_Loic.pdf

Because of their huge phenotypic diversity (10,000 species), birds were able to colonize many “extreme” ecological niches. Many studies have been focus on the polar areas (i.e. Arctic and Antarctica) with their typical cold climate. The aim of this work was to explore the onset of thermoregulatory mechanisms in birds. Using an integrative approach, from whole animal (indirect calorimetry) to gene expression (RT-PCR analysis), we investigated metabolic adaptations and avian uncoupling protein implication in non shivering thermogenesis (NST) during chronic cold exposure. In two studies, working on Muscovy ducklings, we have highlighted the “adaptative” aspect of NST and potential implication of avUCP in this mechanism in relation to different ambient temperatures of acclimation and to cold exposure duration.In a third study, we were interested by passage from shore to marine life of King Penguins that represents a key step of their life. This is defined by massive cold stress (cold water) and increase of physical activity (long-time swimming), leading great metabolic adaptations, such as an increase of lipid oxidative capacities which would sustain expensive energetic cost of marine life. De par leur importante diversité phénotypique (10000 espèces), les oiseaux ont colonisé la plupart des niches écologiques, aussi « extrêmes » soient-elles. Les zones polaires (Arctique et Antarctiques) et le climat extrêmement froid qui les aractérise, suscitent l’intérêt de nombreuses études. Ce travail de thèse avait pour but d’explorer les différents mécanismes intervenant dans la mise en place de la thermorégulation chez l’oiseau. Nous nous sommes principalement intéressés, par une approche intégrative, de l’animal entier (méthodes de calorimétrie indirecte) à l’expression génique (techniques de RT-PCR), à caractériser les modifications métaboliques et l’implication d’une protéine découplante (avUCP) dans les mécanismes de thermorégulation, et principalement la thermogenèse sans frisson (NST) en réponse à une exposition ...