Immunosenescence in the wild? A longitudinal study in a long‐lived seabird

• Published in: Journal of Animal Ecology
• Main Authors: Bichet, Coraline, Moiron, Maria, Matson, Kevin, Vedder, Oscar, Bouwhuis, Sandra
• Other Authors: Institute of Avian Research Germany, Centre d'Études Biologiques de Chizé - UMR 7372 (CEBC), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD France-Sud )-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Université de Montpellier (UM), Wildlife Ecology and Conservation The Netherlands, Wageningen University and Research Wageningen (WUR)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2022
• Subjects: [SDE]Environmental Sciences; Sterna hirundo
• Online Access: https://hal.science/hal-03576801; https://hal.science/hal-03576801/document; https://hal.science/hal-03576801/file/Journal%20of%20Animal%20Ecology%20-%202021%20-%20Bichet%20-%20Immunosenescence%20in%20the%20wild%20A%20longitudinal%20study%20in%20a%20long%25u2010lived%20seabird.pdf; https://doi.org/10.1111/1365-2656.13642

International audience Longitudinal studies of various vertebrate populations have demonstrated senescent declines in reproductive performance and survival probability to be almost ubiquitous. Longitudinal studies of potential underlying proximate mechanisms, however, are still scarce. Due to its critical function in the maintenance of health and viability, the immune system is among the potential (mediators of) proximate mechanisms that could underlie senescence. Here, we studied three innate immune parameters—haemagglutination titre, haemolysis titre and haptoglobin concentration—in a population of common terns (Sterna hirundo) known to undergo actuarial senescence. We repeatedly sampled birds of known sex and age across 11 years and used random regression models to (a) quantify how immune parameters vary among individuals and (b) describe within-individual age-specific changes in, and potential trade-offs between, immune parameters. Our models revealed no differences between males and females in haemagglutination titre and haptoglobin concentration, and very low among-individual variation in these parameters in general. Within individuals, haemagglutination titre increased with age, while haptoglobin concentration did not change. We found no indication for selective (dis)appearance in relation to haemagglutination titre or haptoglobin concentration, nor for the existence of a trade-off between them. Haemolysis was absent in the majority (76%) of samples. Common terns do not exhibit clear senescence in haemagglutination titre and haptoglobin concentration and show very little among-individual variation in these parameters in general. This may be explained by canalisation of the immune parameters or by the colonial breeding behaviour of our study species, but more longitudinal studies are needed to facilitate investigation of links between species’ characteristics and immunosenescence in wild animals.