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Fleischer R, Jones C, Ledezma-Campos P, Czirják GÁ, Sommer S, Gillespie TR, Vicente-Santos A. Gut microbial shifts in vampire bats linked to immunity due to changed diet in human disturbed landscapes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 907:167815. [PMID: 37852483 DOI: 10.1016/j.scitotenv.2023.167815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 09/14/2023] [Accepted: 10/11/2023] [Indexed: 10/20/2023]
Abstract
Anthropogenic land-use change alters wildlife habitats and modifies species composition, diversity, and contacts among wildlife, livestock, and humans. Such human-modified ecosystems have been associated with emerging infectious diseases, threatening human and animal health. However, human disturbance also creates new resources that some species can exploit. Common vampire bats (Desmodus rotundus) in Latin America constitute an important example, as their adaptation to human-modified habitats and livestock blood-feeding has implications for e.g., rabies transmission. Despite the well-known links between habitat degradation and disease emergence, few studies have explored how human-induced disturbance influences wildlife behavioural ecology and health, which can alter disease dynamics. To evaluate links among habitat disturbance, diet shifts, gut microbiota, and immunity, we quantified disturbance around roosting caves of common vampire bats in Costa Rica, measured their long-term diet preferences (livestock or wildlife blood) using stable isotopes of carbon and nitrogen, evaluated innate and adaptive immune markers, and characterized their gut microbiota. We observed that bats from roosting caves with more cattle farming nearby fed more on cattle blood. Moreover, gut microbial richness and the abundance of specific gut microbes differed according to feeding preferences. Interestingly, bats feeding primarily on wildlife blood harboured a higher abundance of the bacteria Edwardsiella sp., which tended to be associated with higher immunoglobulin G levels. Our results highlight how human land-use change may indirectly affect wildlife health and emerging infectious diseases through diet-induced shifts in microbiota, with implications for host immunity and potential consequences for susceptibility to pathogens.
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Affiliation(s)
- Ramona Fleischer
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany.
| | - Christie Jones
- Department of Environmental Sciences, Emory University, Atlanta, GA, USA; Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | | | - Gábor Á Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Simone Sommer
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Ulm, Germany
| | - Thomas R Gillespie
- Department of Environmental Sciences, Emory University, Atlanta, GA, USA; Department of Environmental Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA; Program in Population Biology, Ecology, and Evolution, Emory University, Atlanta, GA, USA
| | - Amanda Vicente-Santos
- Program in Population Biology, Ecology, and Evolution, Emory University, Atlanta, GA, USA.
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2
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Jennifer T, Emily F, Neuman-Lee LA. Assessment of glucocorticoids, sex steroids, and innate immunity in wild red-eared slider turtles (Trachemys scripta elegans). Gen Comp Endocrinol 2023; 339:114288. [PMID: 37060930 DOI: 10.1016/j.ygcen.2023.114288] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 03/21/2023] [Accepted: 04/11/2023] [Indexed: 04/17/2023]
Abstract
When access to resources is limited, organisms must shift energy investment among physiological processes to survive, reproduce, and respond to unpredictable events. The shifting of these limited resources among processes may result in physiological tradeoffs, often mediated by glucocorticoids. We assessed relationships among the physiological processes of immunity, reproduction, and the stress response in wild adult red-eared slider turtles (Trachemys scripta elegans). Red-eared sliders exhibit a multi-clutching reproductive strategy that requires high energetic investment in reproduction at the beginning of the nesting season in females. Males mate in spring and undergo spermatogenesis and mating in late summer/early fall. We expected to observe tradeoffs when investment toward reproductive processes was particularly demanding. To test this, we subjected 123 individuals to a standardized acute stressor and collected blood to measure innate immunocompetence and circulating steroid hormone concentrations. Tradeoffs between female reproduction and immunocompetence occurred early in the nesting season. This high reproductive investment was evident by heightened circulating progesterone and reduced baseline innate immunity. Corticosterone (CORT) was also high during this period, indicating a role in facilitating allocation of energy. Tradeoffs were not as evident in males, though males upregulated innate immune function, baseline CORT, and testosterone prior to fall spermatogenesis and mating. Throughout the entire sampling period, both males and females increased CORT and immunocompetence following the acute standardized stressor. Taken together, we concluded that reproduction requires shifts in energy allocation in during the highest reproductive period for females but all individuals in this population remain able to respond to the standardized stressor even during increased reproductive investment. These findings reinforce the continuing evidence that physiological relationships are context-dependent and resource demands are dynamic across the reproductive season.
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Affiliation(s)
- Terry Jennifer
- Arkansas State University, PO Box 599, State University, Arkansas, 72467, USA.
| | - Field Emily
- Arkansas State University, PO Box 599, State University, Arkansas, 72467, USA; Mississippi Department of Wildlife, Fisheries, and Parks, Mississippi Museum of Natural Science, 2148 Riverside Drive Jackson, MS 39202
| | - Lorin A Neuman-Lee
- Arkansas State University, PO Box 599, State University, Arkansas, 72467, USA
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3
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Rivera-Ruiz DA, Flores-Martínez JJ, Rosales C, Herrera Montalvo LG. Constitutive Innate Immunity of Migrant and Resident Long-Nosed Bats (Leptonycteris yerbabuenae) in the Drylands of Mexico. DIVERSITY 2023. [DOI: 10.3390/d15040530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Abstract
In contrast to birds, the relationship between migration and immunity has been scarcely studied in bats. We examined how the expression of the humoral portion of the constitutive immunity varied in a bat with partial, sex-biased migration: the lesser long-nosed bat (Leptonycteris yerbabuenae (Phyllostomidae)). The lesser long-nosed bat is a nectarivorous species distributed in the arid and semi-arid regions of North and Central America. We evaluated the bacteria-killing abilities (BKAs) of the plasma of male and female lesser long-nosed bats on the Pacific coast in different periods of the year. Because adult males are resident, they were used to explore the effect of reproductive activity on BKA, and we predicted higher values in mating males (i.e., individuals presenting scrotal testicles and a fresh dorsal patch). In contrast to males, most females migrate to cactus deserts in northern Mexico during pregnancy and lactation, and then return to the dry forests of west-central Mexico to mate. We predicted that the combined effect of breeding and migration would have an adverse effect on BKA; therefore, migratory pregnant and lactating females were expected to exhibit a lower BKA than mating females in west-central Mexico. We compared the BKAs of females captured in October and December in central Mexico, and we predicted that migratory females that had recently arrived in October should exhibit a lower BKA than females captured two months later. In addition, we compared the BKAs between lactating females and young in northern Mexico and predicted lower values in recently born individuals. We found that the BKAs of males were higher in reproductive individuals than in non-reproductive individuals. We found a significant difference in the BKAs between females at the two extremes of their migratory range: the values of pregnant females in Sonora and females in December were higher than those of females captured in October. Finally, we found no difference in BKAs between lactating females and young individuals. Our findings indicate that the basal levels of the innate humoral component are heightened in mating males, that this response is reduced in females that recently returned to their mating grounds, and that the constitutive immunity of young individuals matures early, probably in anticipation of the potential to encounter pathogens during their migration to west-central Mexico.
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Affiliation(s)
- David A. Rivera-Ruiz
- Posgrado en Ciencias Biológicas, Unidad de Posgrado, Edificio D, 1° Piso, Circuito de Posgrados, Ciudad Universitaria, Coyoacán 04510, Ciudad de México, Mexico
- Estación de Biología Chamela, Instituto de Biología, Universidad Nacional Autónoma de México, Apartado Postal 21, San Patricio 48989, Jalisco, Mexico
| | - José Juan Flores-Martínez
- Laboratorio de Sistemas de Información Geográfica, Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Coyoacán 04510, Ciudad de México, Mexico
| | - Carlos Rosales
- Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Circuito Exterior s/n, Ciudad Universitaria, Coyacán 04510, Ciudad de México, Mexico
| | - Luis Gerardo Herrera Montalvo
- Estación de Biología Chamela, Instituto de Biología, Universidad Nacional Autónoma de México, Apartado Postal 21, San Patricio 48989, Jalisco, Mexico
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CLINICOPATHOLOGIC EVALUATION OF AN EX SITU POPULATION OF ADULT AFRICAN WHITE-BELLIED PANGOLIN (PHATAGINUS TRICUSPIS). J Zoo Wildl Med 2022; 53:551-560. [DOI: 10.1638/2021-0055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2022] [Indexed: 11/21/2022] Open
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5
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Rissmann M, Friedrichs V, Kley N, Straube M, Sadeghi B, Balkema-Buschmann A. Baseline of Physiological Body Temperature and Hematological Parameters in Captive Rousettus aegyptiacus and Eidolon helvum Fruit Bats. Front Physiol 2022; 13:910157. [PMID: 36105294 PMCID: PMC9465388 DOI: 10.3389/fphys.2022.910157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 06/16/2022] [Indexed: 11/30/2022] Open
Abstract
The discovery of bats as reservoir hosts for a number of highly pathogenic zoonotic agents has led to an increasing interest of infectious disease research in experimental studies with bats. Therefore, we established breeding colonies of Rousettus aegyptiacus and Eidolon helvum fruit bats, which both have been identified as reservoir hosts for relevant zoonotic disease agents, such as Marburg virus and Lagos bat virus. Since 2013, individuals of both species have been recruited to the Friedrich-Loeffler-Institut (FLI) from zoological gardens in Europe, to where these species had been introduced from the wild several decades ago. The aviaries have been designed according to national recommendations published by the Federal Ministry of Agriculture. Under these conditions, both species have been reproducing for years. To better understand the physiology of these animals, and to generate baseline knowledge for infection experiments, we monitored the body core temperatures of R. aegyptiacus bats in the aviaries, and found a circadian variation between 34°C and 41.5°C. We also determined the hematological parameters of both species, and detected specific differences between both bat species. For values of clinical chemistry, no correlation to age or sex was observed. However, species-specific differences were detected since ALT, BUN and CREA were found to be significantly higher in R. aegyptiacus and GLU and TP were significantly higher in E. helvum bats. A higher hematocrit, hemoglobin and red blood cell level was observed in subadult R. aegyptiacus, with hemoglobin and red blood cells also being significantly increased compared to E. helvum. Lymphocytes were found to be the dominant white blood cells in both species and are higher in female E. helvum. Neutrophil granulocytes were significantly higher in E. helvum bats. This underlines the necessity to define baseline profiles for each bat species prior to their use in experimental challenge.
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Affiliation(s)
- Melanie Rissmann
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Greifswald, Germany
- Department of Viroscience, Erasmus MC, Rotterdam, Netherlands
| | | | - Nils Kley
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Martin Straube
- Landratsamt Ortenaukreis, Amt für Veterinärwesen und Lebensmittelüberwachung, Offenburg, Germany
| | - Balal Sadeghi
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Greifswald, Germany
| | - Anne Balkema-Buschmann
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Greifswald, Germany
- *Correspondence: Anne Balkema-Buschmann,
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6
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Bichet C, Régis C, Gilot‐Fromont E, Cohas A. Variations in immune parameters with age in a wild rodent population and links with survival. Ecol Evol 2022; 12:e9094. [PMID: 35845372 PMCID: PMC9273568 DOI: 10.1002/ece3.9094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 06/14/2022] [Accepted: 06/20/2022] [Indexed: 12/02/2022] Open
Abstract
Recent findings suggest that immune functions do not unidirectionally deteriorate with age but that a potentially adaptive remodeling, where functions of the immune system get downregulated while others get upregulated with age could also occur. Scarce in wild populations, longitudinal studies are yet necessary to properly understand the patterns and consequences of age variations of the immune system in the wild. Meanwhile, it is challenging to understand if the observed variations in immune parameters with age are due to changes at the within-individual level or to selective (dis)appearance of individuals with peculiar immune phenotypes. Thanks to a long-term and longitudinal monitoring of a wild Alpine marmot population, we aimed to understand within- and between-individual variation in the immune phenotype with age, in order to improve our knowledge about the occurrence and the evolutionary consequences of such age variations in the wild. To do so, we recorded the age-specific leukocyte concentration and leukocyte profile in repeatedly sampled dominant individuals. We then tested whether the potential changes with age were attributable to within-individual variations and/or selective (dis)appearance. Finally, we investigated if the leukocyte concentration and profiles were correlated to the probability of death at a given age. The leukocyte concentration was stable with age, but the relative number of lymphocytes decreased, while the relative number of neutrophils increased, over the course of an individual's life. Moreover, between individuals of the same age, individuals with fewer lymphocytes but more neutrophils were more likely to die. Therefore, selective disappearance seems to play a role in the age variations of the immune parameters in this population. Further investigations linking age variations in immune phenotype to individual fitness are needed to understand whether remodeling of the immune system with age could or could not be adaptive.
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Affiliation(s)
- Coraline Bichet
- Centre d'Etudes Biologiques de ChizéCNRS‐La Rochelle UniversitéVilliers‐en‐BoisFrance
- Institut für Vogelforschung "Vogelwarte Helgoland" (Institute of Avian Research)WilhelmshavenGermany
- UMR‐CNRS 5558, Laboratoire Biométrie et Biologie ÉvolutiveUniversité Claude Bernard Lyon 1VilleurbanneFrance
| | - Corinne Régis
- UMR‐CNRS 5558, Laboratoire Biométrie et Biologie ÉvolutiveUniversité Claude Bernard Lyon 1VilleurbanneFrance
| | - Emmanuelle Gilot‐Fromont
- UMR‐CNRS 5558, Laboratoire Biométrie et Biologie ÉvolutiveUniversité Claude Bernard Lyon 1VilleurbanneFrance
- Université de Lyon, VetAgro SupMarcy‐l'EtoileFrance
| | - Aurélie Cohas
- UMR‐CNRS 5558, Laboratoire Biométrie et Biologie ÉvolutiveUniversité Claude Bernard Lyon 1VilleurbanneFrance
- Institut Universitaire de France (IUF)ParisFrance
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7
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Rogers EJ, McGuire L, Longstaffe FJ, Clerc J, Kunkel E, Fraser E. Relating wing morphology and immune function to patterns of partial and differential bat migration using stable isotopes. J Anim Ecol 2022; 91:858-869. [PMID: 35218220 DOI: 10.1111/1365-2656.13681] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 01/26/2022] [Indexed: 11/28/2022]
Abstract
Migration is energetically expensive and is predicted to drive similar morphological adaptations and physiological trade-offs in migratory bats and birds. Previous studies suggest that fixed traits like wing morphology vary among species and individuals according to selective pressures on flight, while immune defenses can vary flexibly within individuals as energy is variably reallocated throughout the year. We assessed intraspecific variation in wing morphology and immune function in silver-haired bats (Lasionycteris noctivagans), a species that follows both partial and differential migration patterns. We hypothesized that if bats experience energy constraints associated with migration, then wing morphology and immune function should vary based on migratory tendency (sedentary or migratory) and migration distance. We predicted that long-distance migrants would have reduced immune function and more migration-adapted wing shapes compared to resident or short-distance migrating bats. We estimated breeding latitude of spring migrants using stable hydrogen isotope techniques. Our sample consisted primarily of male bats, which we categorized as residents, long-distance northern migrants, short-distance northern migrants, and southern migrants (apparent breeding location south of capture site). Controlling for individual condition and capture date, we related wing characteristics and immune indices among groups. Some, but not all, aspects of wing form and immune function varied between migrants and residents. Long-distance northern migrants had larger wings than short-distance northern migrants and lower wing loading than southern migrants. Compared with resident bats, short-distance northern migrants had reduced IgG while southern migrants had heightened neutrophils and neutrophil-to-lymphocyte ratios. Body fat, aspect ratio, wing tip shape, and bacteria killing ability did not vary with migration status or distance. In general, male silver-haired bats do not appear to mediate migration costs by substantially downregulating immune defenses or to be under stronger selection for wing forms adapted for fast, energy-efficient flight. Such phenotypic changes may be more adaptive for female silver-haired bats, which migrate farther and are more constrained by time in spring than males. Adaptations for aerial hawking and the use of heterothermy by migrating bats may also reduce the energetic cost of migration and the need for more substantial morphological and physiological trade-offs.
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Affiliation(s)
- Elizabeth J Rogers
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA.,Organismic and Evolutionary Biology Program, University of Massachusetts, Amherst, MA, USA
| | - Liam McGuire
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA.,Department of Biology, University of Waterloo, Waterloo, ON, Canada
| | - Fred J Longstaffe
- Department of Earth Sciences, The University of Western Ontario, London, ON, Canada
| | - Jeff Clerc
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA.,Normandeau Associates Inc, Gainesville, FL, USA
| | - Emma Kunkel
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA
| | - Erin Fraser
- Environmental Science Program, Memorial University of Newfoundland (Grenfell Campus), Corner Brook, NL, Canada
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8
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Roast MJ, Hidalgo Aranzamendi N, Teunissen N, Fan M, Verhulst S, Peters A. No Evidence for Constitutive Innate Immune Senescence in a Longitudinal Study of a Wild Bird. Physiol Biochem Zool 2021; 95:54-65. [PMID: 34870562 DOI: 10.1086/717937] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractAging is associated with declines in physiological performance; declining immune defenses particularly could have consequences for age-related fitness and survival. In aging vertebrates, adaptive (memory-based) immune responses typically become impaired, innate (nonspecific) responses undergo lesser declines, and inflammation increases. Longitudinal studies of immune functions in wild animals are rare, yet they are needed to understand immunosenescence under evolutionarily relevant conditions. Using longitudinal data from a tropical passerine (Malurus coronatus) population, we investigate how population trends emerge from within-individual changes and between-individual heterogeneity (e.g., selective disappearance) in immune status. We quantified constitutive immune indexes (haptoglobin [inflammation associated], natural antibodies, complement [lytic] activity, and heterophil-lymphocyte ratio; n=505-631) in individuals sampled one to seven times over 5 yr. Unexpectedly, longitudinal analyses showed no age-related change within individuals in any immune index, despite sufficient power to detect within-individual change. Between individuals, we found age-related declines in natural antibodies and increases in heterophil-lymphocyte ratios. However, selective disappearance could not adequately explain between-individual age effects, and longitudinal models could not explain our data better than cross-sectional analyses. The lack of clear within-individual immunosenescence is itself notable. Persistent levels of haptoglobin, complement activity, and natural antibodies into old age suggests that these immune components are maintained, potentially with adaptive significance.
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9
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Bichet C, Moiron M, Matson KD, Vedder O, Bouwhuis S. Immunosenescence in the wild? A longitudinal study in a long-lived seabird. J Anim Ecol 2021; 91:458-469. [PMID: 34850397 DOI: 10.1111/1365-2656.13642] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 11/18/2021] [Indexed: 01/03/2023]
Abstract
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.
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Affiliation(s)
- Coraline Bichet
- Institute of Avian Research, Wilhelmshaven, Germany.,Centre d'Etudes Biologiques de Chizé, CNRS-La Rochelle Université, UMR-7372, Villiers-en-Bois, France
| | - Maria Moiron
- Institute of Avian Research, Wilhelmshaven, Germany.,CEFE, Université de Montpellier, CNRS, EPHE, IRD, Université Paul Valéry Montpellier 3, Montpellier, France
| | - Kevin D Matson
- Wildlife Ecology and Conservation, Environmental Sciences Group, Wageningen University, Wageningen, The Netherlands
| | - Oscar Vedder
- Institute of Avian Research, Wilhelmshaven, Germany
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10
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Fritze M, Puechmaille SJ, Costantini D, Fickel J, Voigt CC, Czirják GÁ. Determinants of defence strategies of a hibernating European bat species towards the fungal pathogen Pseudogymnoascus destructans. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 119:104017. [PMID: 33476670 DOI: 10.1016/j.dci.2021.104017] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 01/12/2021] [Accepted: 01/12/2021] [Indexed: 06/12/2023]
Abstract
Pseudogymnoascus destructans (Pd), the causative agent of white-nose syndrome in North America, has decimated bat populations within a decade. The fungus impacts bats during hibernation when physiological functions, including immune responses, are down-regulated. Studies have shown that Pd is native to Europe, where it is not associated with mass mortalities. Moreover, genomic and proteomic studies indicated that European bats may have evolved an effective immune defence, which is lacking in North American bats. However, it is still unclear which defence strategy enables European bats to cope with the pathogen. Here, we analyzed selected physiological and immunological parameters in torpid, Pd infected European greater mouse-eared bats (Myotis myotis) showing three different levels of infection (asymptomatic, mild and severe symptoms). From a subset of the studied bats we tracked skin temperatures during one month of hibernation. Contrasting North American bats, arousal patterns remained unaffected by Pd infections in M. myotis. In general, heavier M. myotis aroused more often from hibernation and showed less severe disease symptoms than lean individuals; most likely because heavy bats were capable of reducing the Pd load more effectively than lean individuals. In the blood of severely infected bats, we found higher gene expression levels of an inflammatory cytokine (IL-1β), but lower levels of an acute phase protein (haptoglobin), reactive oxygen metabolites (ROMs) and plasma non-enzymatic antioxidant capacity (OXY) compared to conspecifics with lower levels of infection. We conclude that M. myotis, and possibly also other European bat species, tolerate Pd infections during torpor by using selected acute phase response parameters at baseline levels, yet without arousing from torpor and without synthesizing additional immune molecules.
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Affiliation(s)
- Marcus Fritze
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany; Institute of Biology, Freie Universität Berlin, Takustr. 6, 14195, Berlin, Germany.
| | - Sebastien J Puechmaille
- Institut des Sciences de L'Evolution, University of Montpellier, CNRS, EPHE, IRD, Montpellier, 34095, Montpellier, France
| | - David Costantini
- Unité Physiologie Moléculaire et Adaptation (PhyMA), Muséum National D'Histoire Naturelle, CNRS, CP32, 57 Rue Cuvier, 75005, Paris, France
| | - Jörns Fickel
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany; Institute for Biochemistry and Biology, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476, Potsdam, Germany
| | - Christian C Voigt
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany; Institute of Biology, Freie Universität Berlin, Takustr. 6, 14195, Berlin, Germany
| | - Gábor Á Czirják
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315, Berlin, Germany
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11
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Becker DJ, Speer KA, Korstian JM, Volokhov DV, Droke HF, Brown AM, Baijnauth CL, Padgett-Stewart T, Broders HG, Plowright RK, Rainwater TR, Fenton MB, Simmons NB, Chumchal MM. Disentangling interactions among mercury, immunity and infection in a Neotropical bat community. J Appl Ecol 2021; 58:879-889. [PMID: 33911313 PMCID: PMC8078557 DOI: 10.1111/1365-2664.13809] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Accepted: 12/01/2020] [Indexed: 12/13/2022]
Abstract
1. Contaminants such as mercury are pervasive and can have immunosuppressive effects on wildlife. Impaired immunity could be important for forecasting pathogen spillover, as many land-use changes that generate mercury contamination also bring wildlife into close contact with humans and domestic animals. However, the interactions among contaminants, immunity and infection are difficult to study in natural systems, and empirical tests of possible directional relationships remain rare. 2. We capitalized on extreme mercury variation in a diverse bat community in Belize to test association among contaminants, immunity and infection. By comparing a previous dataset of bats sampled in 2014 with new data from 2017, representing a period of rapid agricultural land conversion, we first confirmed bat species more reliant on aquatic prey had higher fur mercury. Bats in the agricultural habitat also had higher mercury in recent years. We then tested covariation between mercury and cellular immunity and determined if such relationships mediated associations between mercury and bacterial pathogens. As bat ecology can dictate exposure to mercury and pathogens, we also assessed species-specific patterns in mercury-infection relationships. 3. Across the bat community, individuals with higher mercury had fewer neutrophils but not lymphocytes, suggesting stronger associations with innate immunity. However, the odds of infection for haemoplasmas and Bartonella spp. were generally lowest in bats with high mercury, and relationships between mercury and immunity did not mediate infection patterns. Mercury also showed species- and clade-specific relationships with infection, being associated with especially low odds for haemoplasmas in Pteronotus mesoamericanus and Dermanura phaeotis. For Bartonella spp., mercury was associated with particularly low odds of infection in the genus Pteronotus but high odds in the subfamily Stenodermatinae. 4. Synthesis and application. Lower general infection risk in bats with high mercury despite weaker innate defense suggests contaminant-driven loss of pathogen habitat (i.e. anemia) or vector mortality as possible causes. Greater attention to these potential pathways could help disentangle relationships among contaminants, immunity and infection in anthropogenic habitats and help forecast disease risks. Our results also suggest that contaminants may increase infection risk in some taxa but not others, emphasizing the importance of considering surveillance and management at different phylogenetic scales.
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Affiliation(s)
| | - Kelly A. Speer
- Richard Gilder Graduate School, American Museum of Natural History, New York, NY, USA
- Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, USA
- Center for Conservation Genomics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, USA
| | | | - Dmitriy V. Volokhov
- Center for Biologies Evaluation and Research, Food and Drug Administration, Silver Spring, MD, USA
| | - Hannah F. Droke
- Department of Global and Planetary Health, University of South Florida, Tampa, FL, USA
| | - Alexis M. Brown
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY, USA
| | - Catherene L. Baijnauth
- Sackler Institute of Comparative Genomics, American Museum of Natural History, New York, NY, USA
| | - Ticha Padgett-Stewart
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Hugh G. Broders
- Department of Biology, University of Waterloo, Waterloo, ON, Canada
| | - Raina K. Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Thomas R. Rainwater
- Department of Forestry and Environmental Conservation, Clemson University, Clemson, SC, USA
- Baruch Institute of Coastal Ecology and Forest Science, Clemson University, Georgetown, SC, USA
- Tom Yawkey Wildlife Center, Georgetown, SC, USA
| | - M. Brock Fenton
- Department of Biology, Western University, London, ON, Canada
| | - Nancy B. Simmons
- Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY, USA
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12
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Leivesley JA, Rollinson N. Maternal provisioning and fluctuating thermal regimes enhance immune response in a reptile with temperature-dependent sex determination. J Exp Biol 2021; 224:jeb.237016. [PMID: 33536300 DOI: 10.1242/jeb.237016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Accepted: 01/22/2021] [Indexed: 11/20/2022]
Abstract
The Charnov-Bull model of differential fitness is often used to explain the evolution and maintenance of temperature-dependent sex determination (TSD). Most tests of the model focus on morphological proxies of fitness, such as size traits, whereas early life physiological traits that are closely related to lifetime fitness might provide a framework for generalizing the Charnov-Bull model across taxa. One such trait is the strength of the early-life immune response, which is strongly linked to early-life survival and fitness. Here, we manipulated temperature, variance in temperature, and sex to test the Charnov-Bull model using a physiological trait, immune system strength, in the snapping turtle (Chelydra serpentina). We found no evidence of sex-specific differences in bactericidal capacity of hatchling blood, and no evidence that mean temperature influences bactericidal capacity. However, we did find that fluctuating incubation temperature (i.e. a more naturalized incubation regime) is associated with a greater bactericidal capacity compared with constant temperature incubation. We also found that egg mass, a proxy for maternal provisioning, is positively associated with bactericidal capacity. Our findings suggest that the evolution of temperature-dependent sex determination in reptiles is unrelated to our measure of early-life innate immunity. Our study also underlines how immune response is condition dependent in early life, and questions the biological relevance of constant temperature incubation in experimental studies on ectotherm development.
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Affiliation(s)
- Jessica Alice Leivesley
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada, M5S 3B2
| | - Njal Rollinson
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, Canada, M5S 3B2.,School of the Environment, University of Toronto, Toronto, ON, Canada, M5S 3E8
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13
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Roast MJ, Aranzamendi NH, Fan M, Teunissen N, Hall MD, Peters A. Fitness outcomes in relation to individual variation in constitutive innate immune function. Proc Biol Sci 2020; 287:20201997. [PMID: 33143586 DOI: 10.1098/rspb.2020.1997] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Although crucial for host survival when facing persistent parasite pressure, costly immune functions will inevitably compete for resources with other energetically expensive traits such as reproduction. Optimizing, but not necessarily maximizing, immune function might therefore provide net benefit to overall host fitness. Evidence for associations between fitness and immune function is relatively rare, limiting our potential to understand ultimate fitness costs of immune investment. Here, we assess how measures of constitutive immune function (haptoglobin, natural antibodies, complement activity) relate to subsequent fitness outcomes (survival, reproductive success, dominance acquisition) in a wild passerine (Malurus coronatus). Surprisingly, survival probability was not positively linearly predicted by any immune index. Instead, both low and high values of complement activity (quadratic effect) were associated with higher survival, suggesting that different immune investment strategies might reflect a dynamic disease environment. Positive linear relationships between immune indices and reproductive success suggest that individual heterogeneity overrides potential resource reallocation trade-offs within individuals. Controlling for body condition (size-adjusted body mass) and chronic stress (heterophil-lymphocyte ratio) did not alter our findings in a sample subset with available data. Overall, our results suggest that constitutive immune components have limited net costs for fitness and that variation in immune maintenance relates to individual differences more closely.
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Affiliation(s)
- Michael J Roast
- School of Biological Sciences, Monash University, Victoria 3800, Australia
| | | | - Marie Fan
- School of Biological Sciences, Monash University, Victoria 3800, Australia
| | - Niki Teunissen
- School of Biological Sciences, Monash University, Victoria 3800, Australia
| | - Matthew D Hall
- School of Biological Sciences, Monash University, Victoria 3800, Australia
| | - Anne Peters
- School of Biological Sciences, Monash University, Victoria 3800, Australia
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14
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van Lieshout SHJ, Badás EP, Mason MWT, Newman C, Buesching CD, Macdonald DW, Dugdale HL. Social effects on age-related and sex-specific immune cell profiles in a wild mammal. Biol Lett 2020; 16:20200234. [PMID: 32673548 PMCID: PMC7423055 DOI: 10.1098/rsbl.2020.0234] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Evidence for age-related changes in innate and adaptive immune responses is increasing in wild populations. Such changes have been linked to fitness, and knowledge of the factors driving immune response variation is important for understanding the evolution of immunity. Age-related changes in immune profiles may be owing to factors such as immune system development, sex-specific behaviour and responses to environmental conditions. Social environments may also contribute to variation in immunological responses, for example, through transmission of pathogens and stress arising from resource and mate competition. Yet, the impact of the social environment on age-related changes in immune cell profiles is currently understudied in the wild. Here, we tested the relationship between leukocyte cell composition (proportion of neutrophils and lymphocytes [innate and adaptive immunity, respectively] that were lymphocytes) and age, sex and group size in a wild population of European badgers (Meles meles). We found that the proportion of lymphocytes in early life was greater in males in smaller groups compared to larger groups, but with a faster age-related decline in smaller groups. By contrast, the proportion of lymphocytes in females was not significantly related to age or group size. Our results provide evidence of sex-specific age-related changes in immune cell profiles in a wild mammal, which are influenced by the social environment.
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Affiliation(s)
- Sil H J van Lieshout
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Elisa P Badás
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.,Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
| | - Michael W T Mason
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Chris Newman
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Abingdon, Oxfordshire OX13 5QL, UK
| | - Christina D Buesching
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Abingdon, Oxfordshire OX13 5QL, UK
| | - David W Macdonald
- Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, The Recanati-Kaplan Centre, Abingdon, Oxfordshire OX13 5QL, UK
| | - Hannah L Dugdale
- School of Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.,Groningen Institute for Evolutionary Life Sciences, University of Groningen, 9747 AG Groningen, The Netherlands
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15
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Peters A, Delhey K, Nakagawa S, Aulsebrook A, Verhulst S. Immunosenescence in wild animals: meta‐analysis and outlook. Ecol Lett 2019; 22:1709-1722. [DOI: 10.1111/ele.13343] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 05/30/2019] [Accepted: 06/18/2019] [Indexed: 12/15/2022]
Affiliation(s)
- Anne Peters
- School of Biological Sciences Monash University Clayton Vic. 3800 Australia
| | - Kaspar Delhey
- School of Biological Sciences Monash University Clayton Vic. 3800 Australia
| | - Shinichi Nakagawa
- School of Biological, Earth and Environmental Sciences University of New South Wales Sydney NSW 2052 Australia
| | - Anne Aulsebrook
- School of Biological Sciences Monash University Clayton Vic. 3800 Australia
- School of BioSciences University of Melbourne Parkville Vic. 3010 Australia
| | - Simon Verhulst
- Groningen Institute for Evolutionary Life Sciences University of Groningen 9747 AGGroningen The Netherlands
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16
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Cheynel L, Douhard F, Gilot-Fromont E, Rey B, Débias F, Pardonnet S, Carbillet J, Verheyden H, Hewison AJM, Pellerin M, Gaillard JM, Lemaître JF. Does body growth impair immune function in a large herbivore? Oecologia 2018; 189:55-68. [PMID: 30470888 DOI: 10.1007/s00442-018-4310-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 11/16/2018] [Indexed: 11/26/2022]
Abstract
According to the principle of allocation, trade-offs are inevitable when resources allocated to one biological function are no longer available for other functions. Growth, and to a lesser extent, immunity are energetically costly functions that may compete with allocation to reproductive success and survival. However, whether high allocation to growth impairs immune system development during the growing period or immune system performance during adulthood is currently unknown in wild mammals. Using three roe deer (Capreolus capreolus) populations experiencing contrasting environmental conditions, we tested for potential costs of growth on immune phenotype over both the short-term (during growth), and the long-term (during adulthood) over the course of an individuals' life. We investigated potential costs on a set of 12 immune traits that reflect both innate and adaptive responses, and compared them between sexes and populations. Although fast growth tended to be associated with low levels of some humoral traits (globulins) during the growing period and some cellular immune traits (i.e. eosinophil and neutrophil counts) during adulthood, evidence for a trade-off between growth and other immune components was limited. Unexpectedly, no detectable growth costs on immunity were found in females from the population experiencing the least favourable environment. We discuss our findings in the light of the complex interplay between resource allocation strategies among reproduction, maintenance and immunity, in relation to local environmental conditions experienced by roe deer.
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Affiliation(s)
- L Cheynel
- Université de Lyon, Université Lyon 1, UMR CNRS 5558, Villeurbanne Cedex, France.
| | - F Douhard
- GenPhySE, Université de Toulouse, INRA, INPT, INP-ENVT, 31320, Castanet Tolosan, France
| | - E Gilot-Fromont
- Université de Lyon, Université Lyon 1, UMR CNRS 5558, Villeurbanne Cedex, France
- Université de Lyon, VetAgro Sup, Marcy-l'Etoile, France
| | - B Rey
- Université de Lyon, Université Lyon 1, UMR CNRS 5558, Villeurbanne Cedex, France
| | - F Débias
- Université de Lyon, Université Lyon 1, UMR CNRS 5558, Villeurbanne Cedex, France
| | - S Pardonnet
- Université de Lyon, Université Lyon 1, UMR CNRS 5558, Villeurbanne Cedex, France
| | - J Carbillet
- CEFS, Université de Toulouse, INRA, Castanet Tolosan, France
| | - H Verheyden
- CEFS, Université de Toulouse, INRA, Castanet Tolosan, France
| | - A J M Hewison
- CEFS, Université de Toulouse, INRA, Castanet Tolosan, France
| | - M Pellerin
- Office National de la Chasse et de la Faune Sauvage, Centre National de Recherches Appliquées sur les Cervidés-Sanglier, Bar-le-Duc, France
| | - J-M Gaillard
- Université de Lyon, Université Lyon 1, UMR CNRS 5558, Villeurbanne Cedex, France
| | - J-F Lemaître
- Université de Lyon, Université Lyon 1, UMR CNRS 5558, Villeurbanne Cedex, France
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17
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Whiting JR, Magalhaes IS, Singkam AR, Robertson S, D'Agostino D, Bradley JE, MacColl ADC. A genetics-based approach confirms immune associations with life history across multiple populations of an aquatic vertebrate (Gasterosteus aculeatus). Mol Ecol 2018; 27:3174-3191. [PMID: 29924437 PMCID: PMC6221044 DOI: 10.1111/mec.14772] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Revised: 05/10/2018] [Accepted: 05/10/2018] [Indexed: 12/15/2022]
Abstract
Understanding how wild immune variation covaries with other traits can reveal how costs and trade‐offs shape immune evolution in the wild. Divergent life history strategies may increase or alleviate immune costs, helping shape immune variation in a consistent, testable way. Contrasting hypotheses suggest that shorter life histories may alleviate costs by offsetting them against increased mortality, or increase the effect of costs if immune responses are traded off against development or reproduction. We investigated the evolutionary relationship between life history and immune responses within an island radiation of three‐spined stickleback, with discrete populations of varying life histories and parasitism. We sampled two short‐lived, two long‐lived and an anadromous population using qPCR to quantify current immune profile and RAD‐seq data to study the distribution of immune variants within our assay genes and across the genome. Short‐lived populations exhibited significantly increased expression of all assay genes, which was accompanied by a strong association with population‐level variation in local alleles and divergence in a gene that may be involved in complement pathways. In addition, divergence around the eda gene in anadromous fish is likely associated with increased inflammation. A wider analysis of 15 populations across the island revealed that immune genes across the genome show evidence of having diverged alongside life history strategies. Parasitism and reproductive investment were also important sources of variation for expression, highlighting the caution required when assaying immune responses in the wild. These results provide strong, gene‐based support for current hypotheses linking life history and immune variation across multiple populations of a vertebrate model.
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Affiliation(s)
- James R Whiting
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK.,School of Life Sciences, University of Sussex, Falmer, Brighton, UK
| | - Isabel S Magalhaes
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK.,Department of Life Sciences, Whitelands College, University of Roehampton, London, UK
| | - Abdul R Singkam
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK.,Pendidikan Biologi JPMIPA FKIP, University of Bengkulu, Bengkulu, Indonesia
| | - Shaun Robertson
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK.,Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - Daniele D'Agostino
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK
| | - Janette E Bradley
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK
| | - Andrew D C MacColl
- School of Life Sciences, University of Nottingham, University Park, Nottingham, UK
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18
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Seasonal effects on behavior and immunity in a precocial rodent. Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2513-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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19
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Phelps KL, Kingston T. Environmental and biological context modulates the physiological stress response of bats to human disturbance. Oecologia 2018; 188:41-52. [PMID: 29858693 DOI: 10.1007/s00442-018-4179-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 05/29/2018] [Indexed: 11/28/2022]
Abstract
Environmental and biological context play significant roles in modulating physiological stress responses of individuals in wildlife populations yet are often overlooked when evaluating consequences of human disturbance on individual health and fitness. Furthermore, most studies gauge individual stress responses based on a single physiological biomarker, typically circulating glucocorticoid concentrations, which limits interpretation of the complex, multifaceted responses of individuals to stressors. We selected four physiological biomarkers to capture short-term and prolonged stress responses in a widespread cave-roosting bat, Hipposideros diadema, across multiple gradients of human disturbance in and around caves in the Philippines. We used conditional inference trees and random forest analysis to determine the role of environmental quality (cave complexity, available roosting area), assemblage composition (intra- and interspecific associations and species richness), and intrinsic characteristics of individuals (sex and reproductive status) in modulating responses to disturbance. Direct cave disturbance (hunting pressure and human visitation) was the primary driver of neutrophil-to-lymphocyte ratios, with lower ratios associated with increased disturbance, while context-specific factors were more important in explaining total leukocyte count, body condition, and ectoparasite load. Moreover, conditional inference trees revealed complex interactions among human disturbance and modulating factors. Cave complexity often ameliorated individual responses to human disturbance, whereas conspecific abundance often compounded responses. Our study demonstrates the importance of an integrated approach that incorporates environmental and biological context when identifying drivers of physiological responses, and that assesses responses to gradients of direct and indirect disturbance using multiple complementary biomarkers.
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Affiliation(s)
- Kendra L Phelps
- Department of Biological Sciences, Texas Tech University, Lubbock, USA. .,Southeast Asian Bat Conservation Research Unit, Lubbock, USA. .,EcoHealth Alliance, 460 West 34th Street, New York, NY, 10001, USA.
| | - Tigga Kingston
- Department of Biological Sciences, Texas Tech University, Lubbock, USA.,Southeast Asian Bat Conservation Research Unit, Lubbock, USA
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20
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Ruoss S, Becker NI, Otto MS, Czirják GÁ, Encarnação JA. Effect of sex and reproductive status on the immunity of the temperate bat Myotis daubentonii. Mamm Biol 2018; 94:120-126. [PMID: 32218715 PMCID: PMC7091572 DOI: 10.1016/j.mambio.2018.05.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 05/22/2018] [Indexed: 12/17/2022]
Abstract
Studies of immunity in bat species are rare. However, it is important to determine immunological variations to identify factors influencing the health status of these endangered mammals from an evolutionary, ecological, conservation, and public health point of view. Immunity is highly variable and can be influenced by both internal (e.g. hormone levels, energy demand) and external factors (e.g. pathogens, climate). As bats have some peculiar ecological, energetic, and putative immunological characteristics, they are outstanding study organisms for ecoimmunological studies. We tested if (i) female bats have a higher immunity than males similar to most other mammalian species and (ii) individuals differ according to their energy demand (e.g. reproductive status). To study these questions, we sampled female and male Myotis daubentonii with different reproductive states and estimated their bacterial killing activity, hemolysis/hemagglutination titer, immunoglobulin G (IgG) concentration, and total and differential white blood cell counts. These methods characterize the cellular and humoral branches of both the adaptive and the innate immune responses of these individuals. Reproductively active males had lower cellular immunity compared to non-reproductive individuals. Pregnant females had increased IgG concentrations while hemolysis was enhanced during lactation. No clear trade-off between immunity and reproduction was found; instead immunity of males and female bats seems to be modulated differently due to varying hormonal and energetic states. Our data suggest that both adaptive and innate immunity as well as individual differences (i.e. sex and reproductive state) need to be considered to get a comprehensive overall picture of immunity in wild mammals.
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Affiliation(s)
- Sara Ruoss
- Mammalian Ecology Group, Department of Animal Ecology and Systematics, Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26 (IFZ), 35392 Giessen, Germany
| | - Nina I. Becker
- Institute for Applied Animal Ecology and Ecoinformatics (inatu.re), Im Brühl 2, 35457 Lollar, Germany
| | - Matthias S. Otto
- Mammalian Ecology Group, Department of Animal Ecology and Systematics, Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26 (IFZ), 35392 Giessen, Germany
| | - Gábor Á. Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Str. 17, 10315 Berlin, Germany
| | - Jorge A. Encarnação
- Mammalian Ecology Group, Department of Animal Ecology and Systematics, Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26 (IFZ), 35392 Giessen, Germany
- Institute for Applied Animal Ecology and Ecoinformatics (inatu.re), Im Brühl 2, 35457 Lollar, Germany
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21
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Becker DJ, Czirják GÁ, Volokhov DV, Bentz AB, Carrera JE, Camus MS, Navara KJ, Chizhikov VE, Fenton MB, Simmons NB, Recuenco SE, Gilbert AT, Altizer S, Streicker DG. Livestock abundance predicts vampire bat demography, immune profiles and bacterial infection risk. Philos Trans R Soc Lond B Biol Sci 2018; 373:20170089. [PMID: 29531144 PMCID: PMC5882995 DOI: 10.1098/rstb.2017.0089] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2017] [Indexed: 12/14/2022] Open
Abstract
Human activities create novel food resources that can alter wildlife-pathogen interactions. If resources amplify or dampen, pathogen transmission probably depends on both host ecology and pathogen biology, but studies that measure responses to provisioning across both scales are rare. We tested these relationships with a 4-year study of 369 common vampire bats across 10 sites in Peru and Belize that differ in the abundance of livestock, an important anthropogenic food source. We quantified innate and adaptive immunity from bats and assessed infection with two common bacteria. We predicted that abundant livestock could reduce starvation and foraging effort, allowing for greater investments in immunity. Bats from high-livestock sites had higher microbicidal activity and proportions of neutrophils but lower immunoglobulin G and proportions of lymphocytes, suggesting more investment in innate relative to adaptive immunity and either greater chronic stress or pathogen exposure. This relationship was most pronounced in reproductive bats, which were also more common in high-livestock sites, suggesting feedbacks between demographic correlates of provisioning and immunity. Infection with both Bartonella and haemoplasmas were correlated with similar immune profiles, and both pathogens tended to be less prevalent in high-livestock sites, although effects were weaker for haemoplasmas. These differing responses to provisioning might therefore reflect distinct transmission processes. Predicting how provisioning alters host-pathogen interactions requires considering how both within-host processes and transmission modes respond to resource shifts.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'.
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Affiliation(s)
- Daniel J Becker
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
- Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA 30602, USA
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, USA
| | - Gábor Á Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Dmitriy V Volokhov
- Center for Biologics Evaluation & Research, U.S. Food & Drug Administration, Rockville, MD, USA
| | - Alexandra B Bentz
- Department of Poultry Science, University of Georgia, Athens, GA, USA
- Department of Biology, Indiana University, Bloomington, IN, USA
| | - Jorge E Carrera
- Facultad de Ciencias, Universidad Nacional de Piura, Piura, Perú
- Programa de Conservación de Murciélagos de Perú, Piura, Perú
| | - Melinda S Camus
- Department of Pathology, College of Veterinary Medicine, University of Georgia, Athens, GA, USA
| | - Kristen J Navara
- Department of Poultry Science, University of Georgia, Athens, GA, USA
| | - Vladimir E Chizhikov
- Center for Biologics Evaluation & Research, U.S. Food & Drug Administration, Rockville, MD, USA
| | - M Brock Fenton
- Department of Biology, Western University, London, Ontario, Canada
| | - Nancy B Simmons
- Department of Mammalogy, Division of Vertebrate Zoology, American Museum of Natural History, New York, NY, USA
| | - Sergio E Recuenco
- Department of Preventive Medicine and Public Health, Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Perú
| | - Amy T Gilbert
- National Wildlife Research Center, United States Department of Agriculture, Fort Collins, CO, USA
| | - Sonia Altizer
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
- Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA 30602, USA
| | - Daniel G Streicker
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
- MRC-University of Glasgow Centre for Virus Research, Glasgow, UK
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22
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Hwang J, Kim Y, Lee S, Kim N, Chun M, Lee H, Gottdenker N. Anthropogenic food provisioning and immune phenotype: Association among supplemental food, body condition, and immunological parameters in urban environments. Ecol Evol 2018; 8:3037-3046. [PMID: 29531715 PMCID: PMC5838038 DOI: 10.1002/ece3.3814] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 11/06/2017] [Accepted: 12/11/2017] [Indexed: 11/23/2022] Open
Abstract
Direct or indirect supplemental feeding of free-ranging animals occurs worldwide, resulting in significant impacts on population density or altered demographic processes. Another potential impact of increased energy intake from supplemental feeding is altered immunocompetence. As immune system maintenance is energetically costly, there may be trade-offs between immune responses and other energy-demanding physiological processes in individual animals. Although increased availability of food sources through supplemental feeding is expected to increase the overall immunocompetence of animals, empirical data verifying the association between supplemental feeding and different immune parameters are lacking. Understanding the potential influence of supplemental feeding on immune phenotypes is critical, as it may also impact host-pathogen dynamics in free-ranging animals. Using urban stray cats as a study model, we tested for associations between the intensity of supplemental feeding due to cat caretaker activity (CCA); body condition; and immune phenotype (bacterial killing assay (BKA), immunoglobulin G (IgG) concentration, and leukocyte counts). Significantly higher bacterial killing ability was observed in cats from high CCA districts, whereas higher IgG concentration and eosinophil counts were observed in cats from low CCA districts. Other leukocyte counts and body condition indices showed no significant association with CCA. We observed varying patterns of different immune components in relation to supplemental feeding. Out data suggest that supplemental feeding influences immune phenotype, not only by means of energy provisioning, but also by potentially reducing exposure rates to parasite infections through stray cat behavioral changes.
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Affiliation(s)
- Jusun Hwang
- Department of Veterinary PathologyCollege of Veterinary MedicineUniversity of GeorgiaAthensGAUSA
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Yongbaek Kim
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Sang‐Won Lee
- College of Veterinary MedicineKon‐Kuk UniversitySeoulKorea
| | - Na‐Yon Kim
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Myung‐Sun Chun
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Hang Lee
- College of Veterinary MedicineSeoul National UniversitySeoulKorea
| | - Nicole Gottdenker
- Department of Veterinary PathologyCollege of Veterinary MedicineUniversity of GeorgiaAthensGAUSA
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23
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Cheynel L, Lemaître JF, Gaillard JM, Rey B, Bourgoin G, Ferté H, Jégo M, Débias F, Pellerin M, Jacob L, Gilot-Fromont E. Immunosenescence patterns differ between populations but not between sexes in a long-lived mammal. Sci Rep 2017; 7:13700. [PMID: 29057949 PMCID: PMC5651810 DOI: 10.1038/s41598-017-13686-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 09/22/2017] [Indexed: 11/08/2022] Open
Abstract
In animals, physiological mechanisms underlying reproductive and actuarial senescence remain poorly understood. Immunosenescence, the decline in the ability to display an efficient immune response with increasing age, is likely to influence both reproductive and actuarial senescence through increased risk of disease. Evidence for such a link has been reported from laboratory animal models but has been poorly investigated in the wild, where variation in resource acquisitions usually drives life-history trade-offs. We investigated immunosenescence patterns over 7 years in both sexes of two contrasting roe deer populations (Capreolus capreolus). We first measured twelve immune markers to obtain a thorough identification of innate and adaptive components of immunity and assessed, from the same individuals, the age-dependent variation observed in parasitic infections. Although the level of innate traits was maintained at old age, the functional innate immune traits declined with increasing age in one of two populations. In both populations, the production of inflammatory markers increased with advancing age. Finally, the adaptive response declined in late adulthood. The increasing parasite burden with age we reported suggests the effective existence of immunosenescence. Age-specific patterns differed between populations but not between sexes, which indicate that habitat quality could shape age-dependent immune phenotype in the wild.
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Affiliation(s)
- L Cheynel
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France.
| | - J-F Lemaître
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - J-M Gaillard
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - B Rey
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - G Bourgoin
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
- Université de Lyon, VetAgro Sup, Marcy-l'Etoile, France
| | - H Ferté
- EA 4688 "VECPAR", UFR Pharmacie, Université de Reims Champagne-Ardenne, Reims, France
| | - M Jégo
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - F Débias
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - M Pellerin
- Office National de la Chasse et de la Faune Sauvage, Centre National de Recherches Appliquées sur les Cervidés-Sanglier, Bar-le-Duc, France
| | - L Jacob
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
| | - E Gilot-Fromont
- Univ Lyon, Université Lyon 1; CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, F-69622, Villeurbanne, France
- Université de Lyon, VetAgro Sup, Marcy-l'Etoile, France
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24
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Weise P, Czirják GA, Lindecke O, Bumrungsri S, Voigt CC. Simulated bacterial infection disrupts the circadian fluctuation of immune cells in wrinkle-lipped bats ( Chaerephon plicatus). PeerJ 2017; 5:e3570. [PMID: 28791196 PMCID: PMC5545106 DOI: 10.7717/peerj.3570] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 06/22/2017] [Indexed: 11/29/2022] Open
Abstract
Background Leukocyte concentrations follow a circadian pattern in mammals, with elevated values at times of potential contact with pathogens and parasites. We hypothesized that this pattern is disturbed after an immune challenge. Methods In Thailand, we captured wrinkle-lipped bats (Chaerephon plicatus), when they returned to their colony at dawn. We challenged half of the animals (experimental group) with bacterial lipopolysaccharides and treated the others only with the carrier liquid (control group). We then compared body mass changes and differences in circulating immune cell counts at 8 h post-treatment. Results In experimental animals, we observed an increase in total leukocyte and neutrophil numbers of 17% and 95%, respectively. In control animals, concentrations of leukocytes decreased by 44% and those of neutrophils remained constant. Experimental treatment had no effect on lymphocytes, yet changes in eosinophil numbers were explained by sex. Eosinophils decreased by 66% in females and by 62% in males. Basophils and monocytes were rarest among all observed cell types and analysis was either impossible because of low numbers or yielded no significant effects, respectively. Discussion Our findings show that a simulated bacterial infection triggered a neutrophil-associated immune response in wrinkle-lipped bats, indicating a disruption of the diurnal fluctuation of immune cells. Our study suggests that bats exhibit circadian rhythms in immune cell counts. The magnitude of these fluctuations may vary across species according to specific-specific infection risks associated with colony sizes or specific roosting habits.
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Affiliation(s)
- Philipp Weise
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.,Department of Biology, Humboldt Universität, Berlin, Germany
| | - Gábor A Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Oliver Lindecke
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.,Department of Animal Behaviour, Freie Universität Berlin, Berlin, Germany
| | - Sara Bumrungsri
- Department of Biology, Prince of Songkla University, Hat Yai, Thailand
| | - Christian C Voigt
- Department of Evolutionary Ecology, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany.,Department of Animal Behaviour, Freie Universität Berlin, Berlin, Germany
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25
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Becker DJ, Chumchal MM, Bentz AB, Platt SG, Czirják GÁ, Rainwater TR, Altizer S, Streicker DG. Predictors and immunological correlates of sublethal mercury exposure in vampire bats. ROYAL SOCIETY OPEN SCIENCE 2017; 4:170073. [PMID: 28484633 PMCID: PMC5414270 DOI: 10.1098/rsos.170073] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 03/21/2017] [Indexed: 05/21/2023]
Abstract
Mercury (Hg) is a pervasive heavy metal that often enters the environment from anthropogenic sources such as gold mining and agriculture. Chronic exposure to Hg can impair immune function, reducing the ability of animals to resist or recover from infections. How Hg influences immunity and susceptibility remains unknown for bats, which appear immunologically distinct from other mammals and are reservoir hosts of many pathogens of importance to human and animal health. We here quantify total Hg (THg) in hair collected from common vampire bats (Desmodus rotundus), which feed on blood and are the main reservoir hosts of rabies virus in Latin America. We examine how diet, sampling site and year, and bat demography influence THg and test the consequences of this variation for eight immune measures. In two populations from Belize, THg concentrations in bats were best explained by an interaction between long-term diet inferred from stable isotopes and year. Bats that foraged more consistently on domestic animals exhibited higher THg. However, relationships between diet and THg were evident only in 2015 but not in 2014, which could reflect recent environmental perturbations associated with agriculture. THg concentrations were low relative to values previously observed in other bat species but still correlated with bat immunity. Bats with higher THg had more neutrophils, weaker bacterial killing ability and impaired innate immunity. These patterns suggest that temporal variation in Hg exposure may impair bat innate immunity and increase susceptibility to pathogens such as bacteria. Unexpected associations between low-level Hg exposure and immune function underscore the need to better understand the environmental sources of Hg exposure in bats and the consequences for bat immunity and susceptibility.
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Affiliation(s)
- Daniel J. Becker
- Odum School of Ecology, University of Georgia, Athens, GA, USA
- Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA, USA
- e-mail:
| | | | | | - Steven G. Platt
- Wildlife Conservation Society, Myanmar Program, Yangon, Myanmar
| | - Gábor Á. Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Berlin, Germany
| | - Thomas R. Rainwater
- Tom Yawkey Wildlife Center and Belle W. Baruch Institute of Coastal Ecology and Forest Science, Clemson University, Georgetown, SC, USA
| | - Sonia Altizer
- Odum School of Ecology, University of Georgia, Athens, GA, USA
- Center for the Ecology of Infectious Disease, University of Georgia, Athens, GA, USA
| | - Daniel G. Streicker
- Odum School of Ecology, University of Georgia, Athens, GA, USA
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, UK
- MRC-University of Glasgow Centre for Virus Research, Glasgow G61 1QH, UK
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26
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Liudmila K, Vladimir M, Liudmila C, Vladimir S, Nikolay M. Haematological parameters of pond bats (Myotis dasycneme Boie, 1825 Chiroptera: Vespertilionidae) in the Ural Mountains. ACTA ACUST UNITED AC 2017. [DOI: 10.1080/21658005.2017.1305153] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Kovalchuk Liudmila
- Laboratory of Evolutionary Ecology, Institute of Plant and Animal Ecology, The Ural Branch of the Russian Academy of Sciences, Yekaterinburg, The Russian Federation
| | - Mishchenko Vladimir
- Laboratory of Evolutionary Ecology, Institute of Plant and Animal Ecology, The Ural Branch of the Russian Academy of Sciences, Yekaterinburg, The Russian Federation
- Department of Human and Animal Physiology, The Ural Federal University Named After the First President of Russia B. N. Yeltsin, Yekaterinburg, The Russian Federation
| | - Chernaya Liudmila
- Laboratory of Evolutionary Ecology, Institute of Plant and Animal Ecology, The Ural Branch of the Russian Academy of Sciences, Yekaterinburg, The Russian Federation
| | - Snitko Vladimir
- The Ural Branch of the Russian Academy of Sciences, The Ilmen State Reserve, Miass, The Russian Federation
| | - Mikshevich Nikolay
- Department of Health and Safety, The Ural State Pedagogical University, Yekaterinburg, The Russian Federation
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27
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Beirne C, Waring L, McDonald RA, Delahay R, Young A. Age-related declines in immune response in a wild mammal are unrelated to immune cell telomere length. Proc Biol Sci 2016; 283:20152949. [PMID: 26888036 PMCID: PMC4810837 DOI: 10.1098/rspb.2015.2949] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Senescence has been hypothesized to arise in part from age-related declines in immune performance, but the patterns and drivers of within-individual age-related changes in immunity remain virtually unexplored in natural populations. Here, using a long-term epidemiological study of wild European badgers (Meles meles), we (i) present evidence of a within-individual age-related decline in the response of a key immune-signalling cytokine, interferon-gamma (IFNγ), to ex vivo lymphocyte stimulation, and (ii) investigate three putative drivers of individual variation in the rate of this decline (sex, disease and immune cell telomere length; ICTL). That the within-individual rate of age-related decline markedly exceeded that at the population level suggests that individuals with weaker IFNγ responses are selectively lost from this population. IFNγ responses appeared to decrease with the progression of bovine tuberculosis infection (independent of age) and were weaker among males than females. However, neither sex nor disease influenced the rate of age-related decline in IFNγ response. Similarly, while ICTL also declines with age, variation in ICTL predicted neither among- nor within-individual variation in IFNγ response. Our findings provide evidence of within-individual age-related declines in immune performance in a wild mammal and highlight the likely complexity of the mechanisms that generate them.
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Affiliation(s)
- Christopher Beirne
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| | - Laura Waring
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire GL10 3UJ, UK
| | - Robbie A McDonald
- Environment and Sustainability Institute, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
| | - Richard Delahay
- National Wildlife Management Centre, Animal and Plant Health Agency, Woodchester Park, Gloucestershire GL10 3UJ, UK
| | - Andrew Young
- Centre for Ecology and Conservation, University of Exeter, Penryn Campus, Cornwall TR10 9EZ, UK
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28
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Reichard M. Evolutionary ecology of aging: time to reconcile field and laboratory research. Ecol Evol 2016; 6:2988-3000. [PMID: 27069592 PMCID: PMC4809807 DOI: 10.1002/ece3.2093] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Revised: 02/25/2016] [Accepted: 03/03/2016] [Indexed: 12/19/2022] Open
Abstract
Aging is an increase in mortality risk with age due to a decline in vital functions. Research on aging has entered an exciting phase. Advances in biogerontology have demonstrated that proximate mechanisms of aging and interventions to modify lifespan are shared among species. In nature, aging patterns have proven more diverse than previously assumed. The paradigm that extrinsic mortality ultimately determines evolution of aging rates has been questioned and there appears to be a mismatch between intra‐ and inter‐specific patterns. The major challenges emerging in evolutionary ecology of aging are a lack of understanding of the complexity in functional senescence under natural conditions and unavailability of estimates of aging rates for matched populations exposed to natural and laboratory conditions. I argue that we need to reconcile laboratory and field‐based approaches to better understand (1) how aging rates (baseline mortality and the rate of increase in mortality with age) vary across populations within a species, (2) how genetic and environmental variation interact to modulate individual expression of aging rates, and (3) how much intraspecific variation in lifespan is attributable to an intrinsic (i.e., nonenvironmental) component. I suggest integration of laboratory and field assays using multiple matched populations of the same species, along with measures of functional declines.
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Affiliation(s)
- Martin Reichard
- Institute of Vertebrate Biology Academy of Sciences of the Czech Republic Brno Czech Republic
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29
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Multifactorial processes to slowing the biological clock: Insights from a comparative approach. Exp Gerontol 2015; 71:27-37. [DOI: 10.1016/j.exger.2015.08.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 08/20/2015] [Accepted: 08/29/2015] [Indexed: 02/07/2023]
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30
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Leclaire S, Czirják GÁ, Hammouda A, Gasparini J. Feather bacterial load shapes the trade-off between preening and immunity in pigeons. BMC Evol Biol 2015; 15:60. [PMID: 25881311 PMCID: PMC4392809 DOI: 10.1186/s12862-015-0338-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 03/24/2015] [Indexed: 12/20/2022] Open
Abstract
Background Complex communities of bacteria inhabit the feathers of all birds. Under normal conditions, individuals maintain a healthy state by defending themselves against these potential invaders by preening. The immune system is only triggered when bacteria gain access into the body. Preening is, however, costly and may trade-off with investment in the immune system. To shed light on how birds balance the trade-off between immunity and preen secretions when facing high or low feather bacterial load, we experimentally manipulated feather bacteria load of feral pigeons (Columba livia), and investigated the effects on immune defenses. Results Birds facing high feather bacterial load had lower immune response to PHA skin-swelling test (a measure of induced pro-inflammatory capacity) than controls, while birds facing low feather bacterial load had higher blood bacterial killing ability (a measure of the capacity to eliminate bacterial pathogens) than controls. No other components of the immune system (i.e., hemagglutination and hemolysis capacity of plasma, primary and secondary responses to KLH and quantity of blood parasites) were found to be affected by feather bacterial load. Conclusion Pigeons had previously been shown to adjust preening to feather bacterial load. The decrease in the energetically costly inflammatory response of birds experiencing high bacterial load suggests a trade-off between investment in preen secretion and immunity and reinforces the idea that feather microbiota may have a strong impact on the ecology and evolution of the avian host.
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Affiliation(s)
- Sarah Leclaire
- Sorbonnes Universités, UPMC Université Paris 06, Institut d'Ecologie et des Sciences de l'Environnement de Paris, Paris, F-75005, France. .,CEFE-CNRS, UMR5175, Centre d'Ecologie Fonctionnelle et Evolutive, 1919 Rte de Mende, Montpellier, 34293, France.
| | - Gábor Árpád Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straße 17, Berlin, 10315, Germany.
| | - Abdessalem Hammouda
- Département des Sciences de la Vie, Faculté des Sciences de Gabès, Cité Erriadh, Zrig 6072, Gabès, Tunisia.
| | - Julien Gasparini
- Sorbonnes Universités, UPMC Université Paris 06, Institut d'Ecologie et des Sciences de l'Environnement de Paris, Paris, F-75005, France.
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