1
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Siracusa ER, Pavez-Fox MA, Negron-Del Valle JE, Phillips D, Platt ML, Snyder-Mackler N, Higham JP, Brent LJN, Silk MJ. Social ageing can protect against infectious disease in a group-living primate. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.09.584237. [PMID: 38559098 PMCID: PMC10979879 DOI: 10.1101/2024.03.09.584237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
The benefits of social living are well established, but sociality also comes with costs, including infectious disease risk. This cost-benefit ratio of sociality is expected to change across individuals' lifespans, which may drive changes in social behaviour with age. To explore this idea, we combine data from a group-living primate for which social ageing has been described with epidemiological models to show that having lower social connectedness when older can protect against the costs of a hypothetical, directly transmitted endemic pathogen. Assuming no age differences in epidemiological characteristics (susceptibility to, severity, and duration of infection), older individuals suffered lower infection costs, which was explained largely because they were less connected in their social networks than younger individuals. This benefit of 'social ageing' depended on epidemiological characteristics and was greatest when infection severity increased with age. When infection duration increased with age, social ageing was beneficial only when pathogen transmissibility was low. Older individuals benefited most from having a lower frequency of interactions (strength) and network embeddedness (closeness) and benefited less from having fewer social partners (degree). Our study provides a first examination of the epidemiology of social ageing, demonstrating the potential for pathogens to influence evolutionary dynamics of social ageing in natural populations.
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Affiliation(s)
- Erin R. Siracusa
- School of Psychology, Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
| | | | | | - Daniel Phillips
- Center for Evolution and Medicine, Arizona State University, Arizona, USA
| | - Michael L. Platt
- Department of Neuroscience, University of Pennsylvania, PA, USA
- Department of Psychology, University of Pennsylvania, PA, USA
- Department of Marketing, University of Pennsylvania, PA, USA
| | - Noah Snyder-Mackler
- Center for Evolution and Medicine, Arizona State University, Arizona, USA
- School of Life Sciences, Arizona State University, Arizona, USA
- School for Human Evolution and Social Change, Arizona State University, Arizona, USA
| | - James P. Higham
- Department of Anthropology, New York University, New York, USA
| | - Lauren J. N. Brent
- School of Psychology, Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
| | - Matthew J. Silk
- Institute of Ecology and Evolution, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
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2
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Orbán-Bakk K, Witek M, Dubiec A, Heinze J, Markó B, Csata E. Infection with a non-lethal fungal parasite is associated with increased immune investment in the ant Myrmica scabrinodis. J Invertebr Pathol 2024; 202:108027. [PMID: 38042446 DOI: 10.1016/j.jip.2023.108027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 10/06/2023] [Accepted: 11/28/2023] [Indexed: 12/04/2023]
Abstract
Social insects, such as ants, are preferred host organisms of pathogens and parasites because colonies are densely populated, and the number of potential hosts is high in the same place and time. Within a colony, individuals are exposed differentially to risks according to their function and age. Thus, older individuals forage and are therefore the most exposed to infection, predation, or physical stress, while young workers mostly stay inside the sheltered nest being less exposed. Immune investment is considered to be dependent on an individual's age and pathogen pressure. Long-term exposure to a parasite could affect the immune activity of individuals in an intriguing way that interferes with the age-dependent decline in immunocompetence. However, there are only few cases in which such interferences can be studied. The myrmecopathogenic fungus Rickia wasmannii, which infects entire colonies without killing the workers, is a suitable candidate for such studies. We investigated the general immunocompetence of Myrmica scabrinodis ant workers associated with non-lethal fungal infection by measuring the levels of active phenoloxidase (PO) and total PO (PPO) (reflecting the amount of both active and inactive forms of the enzyme) in two age classes. The level of PO proved to be higher in infected workers than in uninfected ones, while the level of PPO increased with age but was not affected by infection. Overall, these results indicate that a long-term infection could go hand in hand with increased immune activity of ant workers, conferring them higher level of protection.
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Affiliation(s)
- Kincső Orbán-Bakk
- Hungarian Department of Biology and Ecology, Babeș-Bolyai University, 400006 Cluj-Napoca, Clinicilor st. 5-7, Romania; Center for Systems Biology, Biodiversity and Bioresources, Sociobiology and Insect Ecology Lab, Babeș-Bolyai University, 400006 Cluj-Napoca, Clinicilor st. 5-7, Romania.
| | - Magdalena Witek
- Museum and Institute of Zoology, Polish Academy of Sciences, Wilcza 64, 00-679 Warszawa, Poland.
| | - Anna Dubiec
- Museum and Institute of Zoology, Polish Academy of Sciences, Wilcza 64, 00-679 Warszawa, Poland.
| | - Jürgen Heinze
- Institute for Zoology, University of Regensburg, Universitätsstraße 31, D-93040 Regensburg, Germany.
| | - Bálint Markó
- Hungarian Department of Biology and Ecology, Babeș-Bolyai University, 400006 Cluj-Napoca, Clinicilor st. 5-7, Romania; Institute for Research, Development and Innovation in Applied Natural Sciences, Babeș-Bolyai University, Fântânele 30, 400294 Cluj-Napoca, Romania.
| | - Enikő Csata
- Institute for Zoology, University of Regensburg, Universitätsstraße 31, D-93040 Regensburg, Germany.
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3
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Sarkar A, McInroy CJA, Harty S, Raulo A, Ibata NGO, Valles-Colomer M, Johnson KVA, Brito IL, Henrich J, Archie EA, Barreiro LB, Gazzaniga FS, Finlay BB, Koonin EV, Carmody RN, Moeller AH. Microbial transmission in the social microbiome and host health and disease. Cell 2024; 187:17-43. [PMID: 38181740 PMCID: PMC10958648 DOI: 10.1016/j.cell.2023.12.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 12/06/2023] [Accepted: 12/06/2023] [Indexed: 01/07/2024]
Abstract
Although social interactions are known to drive pathogen transmission, the contributions of socially transmissible host-associated mutualists and commensals to host health and disease remain poorly explored. We use the concept of the social microbiome-the microbial metacommunity of a social network of hosts-to analyze the implications of social microbial transmission for host health and disease. We investigate the contributions of socially transmissible microbes to both eco-evolutionary microbiome community processes (colonization resistance, the evolution of virulence, and reactions to ecological disturbance) and microbial transmission-based processes (transmission of microbes with metabolic and immune effects, inter-specific transmission, transmission of antibiotic-resistant microbes, and transmission of viruses). We consider the implications of social microbial transmission for communicable and non-communicable diseases and evaluate the importance of a socially transmissible component underlying canonically non-communicable diseases. The social transmission of mutualists and commensals may play a significant, under-appreciated role in the social determinants of health and may act as a hidden force in social evolution.
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Affiliation(s)
- Amar Sarkar
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA.
| | - Cameron J A McInroy
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Siobhán Harty
- Independent, Tandy Court, Spitalfields, Dublin, Ireland
| | - Aura Raulo
- Department of Biology, University of Oxford, Oxford, UK; Department of Computing, University of Turku, Turku, Finland
| | - Neil G O Ibata
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Mireia Valles-Colomer
- Department of Medicine and Life Sciences, Pompeu Fabra University, Barcelona, Spain; Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
| | - Katerina V-A Johnson
- Institute of Psychology, Leiden University, Leiden, the Netherlands; Department of Psychiatry, University of Oxford, Oxford, UK
| | - Ilana L Brito
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY, USA
| | - Joseph Henrich
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Elizabeth A Archie
- Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA
| | - Luis B Barreiro
- Committee on Immunology, University of Chicago, Chicago, IL, USA; Department of Medicine, University of Chicago, Chicago, IL, USA; Committee on Genetics, Genomics and Systems Biology, University of Chicago, Chicago, IL, USA
| | - Francesca S Gazzaniga
- Molecular Pathology Unit, Cancer Center, Massachusetts General Hospital Research Institute, Charlestown, MA, USA; Department of Pathology, Harvard Medical School, Boston, MA, USA
| | - B Brett Finlay
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, BC, Canada; Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada; Department of Biochemistry, University of British Columbia, Vancouver, BC, Canada
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD, USA
| | - Rachel N Carmody
- Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, USA
| | - Andrew H Moeller
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, USA
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4
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Albery GF, Sweeny AR, Webber Q. How behavioural ageing affects infectious disease. Neurosci Biobehav Rev 2023; 155:105426. [PMID: 37839673 PMCID: PMC10842249 DOI: 10.1016/j.neubiorev.2023.105426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 10/10/2023] [Accepted: 10/12/2023] [Indexed: 10/17/2023]
Abstract
Ageing is associated with profound changes in behaviour that could influence exposure and susceptibility to infectious disease. As well as determining emergent patterns of infection across individuals of different ages, behavioural ageing could interact with, confound, or counteract age-related changes in other traits. Here, we examine how behavioural ageing can manifest and influence patterns of infection in wild animals. We discuss a range of age-related changes that involve interactions between behaviour and components of exposure and susceptibility to infection, including social ageing and immunosenescence, acquisition of novel parasites and pathogens with age, changes in spatial behaviours, and age-related hygiene and sickness behaviours. Overall, most behavioural changes are expected to result in a reduced exposure rate, but there is relatively little evidence for this phenomenon, emerging largely from a rarity of explicit tests of exposure changes over the lifespan. This review offers a framework for understanding how ageing, behaviour, immunity, and infection interact, providing a series of hypotheses and testable predictions to improve our understanding of health in ageing societies.
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Affiliation(s)
- Gregory F Albery
- Department of Biology, Georgetown University, Washington, DC, USA; Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, Scotland, UK; Leibniz Institute of Freshwater Ecology and Inland Fisheries, Berlin, Germany.
| | - Amy R Sweeny
- School of Biosciences, University of Sheffield, Sheffield, England, UK
| | - Quinn Webber
- Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
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5
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Kuenzi AJ, Luis AD. Food availability leads to more connected contact networks among peridomestic zoonotic reservoir hosts. ROYAL SOCIETY OPEN SCIENCE 2023; 10:230809. [PMID: 38026027 PMCID: PMC10646467 DOI: 10.1098/rsos.230809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023]
Abstract
The North American deermouse (Peromyscus maniculatus) is a reservoir host for many zoonotic pathogens. Deermice have been well studied, but few studies have attempted to understand social interactions within the species despite these interactions being key to understanding disease transmission. We performed an experiment to determine if supplemental food or nesting material affected social interactions of deermice and tested if interactions increased with increasing population density. We constructed three simulated buildings that received one of three treatments: food, nesting material, or control. Mice were tagged with passive integrated transponder (PIT) tags, and their movement in and out of buildings was monitored with PIT tag readers. PIT tag readings were used to create contact networks, assuming a contact if two deermice were in the same building at the same time. We found that buildings with food led to contact networks that were approximately 10 times more connected than buildings with nesting material or control buildings. We also saw a significant effect of population density on the average number of contacts per individual. These results suggest that food supplementation which is common in peridomestic settings, can significantly increase contacts between reservoir hosts, potentially leading to increased transmission of zoonotic viruses within the reservoir host and from reservoir hosts to humans.
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Affiliation(s)
- Amy J. Kuenzi
- Department of Biology, Montana Technological University, 1300 Park Street, Butte, MT 59701, USA
| | - Angela D. Luis
- Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, MT 59812, USA
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6
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Schwambergová D, Pátková Ž, Třebická Fialová J, Třebický V, Stella D, Havlíček J. Immunoactivation Affects Perceived Body Odor and Facial but Not Vocal Attractiveness. EVOLUTIONARY PSYCHOLOGY 2023; 21:14747049231218010. [PMID: 38087426 PMCID: PMC10722934 DOI: 10.1177/14747049231218010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 11/16/2023] [Indexed: 12/18/2023] Open
Abstract
Several previous studies have shown that in mammals, the health status of conspecifics can be assessed based on perceptual cues. Olfactory, visual, or acoustic cues may lead to avoidant behavior, thus reducing the risk of contagion by close contact with infected individuals. We tested whether immune system activation after immunization leads to perceptible changes in body odor and facial and vocal attractiveness in humans. We have experimentally activated the immune system of male participants using vaccination against hepatitis A/B and meningococcus. Their body odor, facial photographs, and vocal recordings were collected before and 14 days after vaccination. Subsequently, the body odor samples, facial photographs, and vocal recordings were assessed by female raters for their attractiveness and healthiness. We have also measured skin coloration (from facial photographs and in vivo using a spectrophotometer), vocal parameters, and C-reactive protein (CRP) levels as a marker of inflammation. We found an increase in perceived body odor attractiveness, a decrease in facial attractiveness and healthiness, and no change in vocal attractiveness 14 days after vaccination compared to the prevaccination condition. Moreover, there was no change in facial coloration or vocal parameters between the prevaccination and postvaccination conditions. Prevaccination CRP levels were negatively associated with body odor and facial attractiveness and positively associated with body odor intensity. Overall, our results suggest that perceived body odor as well as facial but not vocal attractiveness may provide cues to activation of the immune response and that each modality may carry specific information about the individual's condition.
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Affiliation(s)
- Dagmar Schwambergová
- Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Žaneta Pátková
- Department of Philosophy and History of Sciences, Faculty of Science, Charles University, Prague, Czech Republic
| | | | - Vít Třebický
- Faculty of Physical Education and Sport, Charles University, Prague, Czech Republic
| | - David Stella
- Department of the Human Dimensions of Global Change, Global Change Research Institute CAS, Brno, Czech Republic
| | - Jan Havlíček
- Department of Zoology, Faculty of Science, Charles University, Prague, Czech Republic
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7
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Kao AB, Hund AK, Santos FP, Young JG, Bhat D, Garland J, Oomen RA, McCreery HF. Opposing Responses to Scarcity Emerge from Functionally Unique Sociality Drivers. Am Nat 2023; 202:302-321. [PMID: 37606948 DOI: 10.1086/725426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2023]
Abstract
AbstractFrom biofilms to whale pods, organisms across taxa live in groups, thereby accruing numerous diverse benefits of sociality. All social organisms, however, pay the inherent cost of increased resource competition. One expects that when resources become scarce, this cost will increase, causing group sizes to decrease. Indeed, this occurs in some species, but there are also species for which group sizes remain stable or even increase under scarcity. What accounts for these opposing responses? We present a conceptual framework, literature review, and theoretical model demonstrating that differing responses to sudden resource shifts can be explained by which sociality benefit exerts the strongest selection pressure on a particular species. We categorize resource-related benefits of sociality into six functionally distinct classes and model their effect on the survival of individuals foraging in groups under different resource conditions. We find that whether, and to what degree, the optimal group size (or correlates thereof) increases, decreases, or remains constant when resource abundance declines depends strongly on the dominant sociality mechanism. Existing data, although limited, support our model predictions. Overall, we show that across a wide diversity of taxa, differences in how group size shifts in response to resource declines can be driven by differences in the primary benefits of sociality.
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8
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Tosa MI, Biel MJ, Graves TA. Bighorn sheep associations: understanding tradeoffs of sociality and implications for disease transmission. PeerJ 2023; 11:e15625. [PMID: 37576510 PMCID: PMC10416771 DOI: 10.7717/peerj.15625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 06/02/2023] [Indexed: 08/15/2023] Open
Abstract
Sociality directly influences mating success, survival rates, and disease, but ultimately likely evolved for its fitness benefits in a challenging environment. The tradeoffs between the costs and benefits of sociality can operate at multiple scales, resulting in different interpretations of animal behavior. We investigated the influence of intrinsic (e.g., relatedness, age) and extrinsic factors (e.g., land cover type, season) on direct contact (simultaneous GPS locations ≤ 25 m) rates of bighorn sheep (Ovis canadensis) at multiple scales near the Waterton-Glacier International Peace Park. During 2002-2012, male and female bighorn were equipped with GPS collars. Indirect contact (GPS locations ≤ 25 m regardless of time) networks identified two major breaks whereas direct contact networks identified an additional barrier in the population, all of which corresponded with prior disease exposure metrics. More direct contacts occurred between same-sex dyads than female-male dyads and between bighorn groups with overlapping summer home ranges. Direct contacts occurred most often during the winter-spring season when bighorn traveled at low speeds and when an adequate number of bighorn were collared in the area. Direct contact probabilities for all dyad types were inversely related to habitat quality, and differences in contact probability were driven by variables related to survival such as terrain ruggedness, distance to escape terrain, and canopy cover. We provide evidence that probabilities of association are higher when there is greater predation risk and that contact analysis provides valuable information for understanding fitness tradeoffs of sociality and disease transmission potential.
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Affiliation(s)
- Marie I. Tosa
- Northern Rocky Mountain Science Center, U.S. Geological Survey, West Glacier, MT, United States of America
| | - Mark J. Biel
- Glacier National Park, National Park Service, West Glacier, MT, United States of America
| | - Tabitha A. Graves
- Northern Rocky Mountain Science Center, U.S. Geological Survey, West Glacier, MT, United States of America
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9
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Gupte PR, Albery GF, Gismann J, Sweeny A, Weissing FJ. Novel pathogen introduction triggers rapid evolution in animal social movement strategies. eLife 2023; 12:e81805. [PMID: 37548365 PMCID: PMC10449382 DOI: 10.7554/elife.81805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/04/2023] [Indexed: 08/08/2023] Open
Abstract
Animal sociality emerges from individual decisions on how to balance the costs and benefits of being sociable. Novel pathogens introduced into wildlife populations should increase the costs of sociality, selecting against gregariousness. Using an individual-based model that captures essential features of pathogen transmission among social hosts, we show how novel pathogen introduction provokes the rapid evolutionary emergence and coexistence of distinct social movement strategies. These strategies differ in how they trade the benefits of social information against the risk of infection. Overall, pathogen-risk-adapted populations move more and have fewer associations with other individuals than their pathogen-risk-naive ancestors, reducing disease spread. Host evolution to be less social can be sufficient to cause a pathogen to be eliminated from a population, which is followed by a rapid recovery in social tendency. Our conceptual model is broadly applicable to a wide range of potential host-pathogen introductions and offers initial predictions for the eco-evolutionary consequences of wildlife pathogen spillover scenarios and a template for the development of theory in the ecology and evolution of animals' movement decisions.
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Affiliation(s)
- Pratik Rajan Gupte
- Groningen Institute for Evolutionary Life Sciences, University of GroningenGroningenNetherlands
| | - Gregory F Albery
- Georgetown UniversityWashingtonUnited States
- Wissenschaftskolleg zu BerlinBerlinGermany
| | - Jakob Gismann
- Groningen Institute for Evolutionary Life Sciences, University of GroningenGroningenNetherlands
| | - Amy Sweeny
- Institute of Evolutionary Biology, University of EdinburghEdinburghUnited Kingdom
| | - Franz J Weissing
- Groningen Institute for Evolutionary Life Sciences, University of GroningenGroningenNetherlands
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10
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Hoekendijk JPA, Grundlehner A, Brasseur S, Kellenberger B, Tuia D, Aarts G. Stay close, but not too close: aerial image analysis reveals patterns of social distancing in seal colonies. ROYAL SOCIETY OPEN SCIENCE 2023; 10:230269. [PMID: 37564067 PMCID: PMC10410205 DOI: 10.1098/rsos.230269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 05/31/2023] [Indexed: 08/12/2023]
Abstract
Many species aggregate in dense colonies. Species-specific spatial patterns provide clues about how colonies are shaped by various (a)biotic factors, including predation, temperature regulation or disease transmission. Using aerial imagery, we examined these patterns in colonies on land of two sympatric seal species: the harbour seal and grey seal. Results show that the density of grey seals on land is twice as high as that of harbour seals. Furthermore, the nearest neighbour distance (NND) of harbour seals (median = 1.06 m) is significantly larger than that of grey seals (median = 0.53 m). Avoidance at small distances (i.e. social distancing) was supported by spatial simulation: when the observed seal locations were shuffled slightly, the frequency of the smallest NNDs (0-25 cm) increased, while the most frequently observed NNDs decreased. As harbour seals are more prone to infectious diseases, we hypothesize that the larger NNDs might be a behavioural response to reduce pathogen transmission. The approach presented here can potentially be used as a practical tool to differentiate between harbour and grey seals in remote sensing applications, particularly in low to medium resolution imagery (e.g. satellite imagery), where morphological characteristics alone are insufficient to differentiate between species.
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Affiliation(s)
- J. P. A. Hoekendijk
- NIOZ Royal Netherlands Institute for Sea Research, 1790AB Den Burg, The Netherlands
- Wageningen University and Research, 6708PB Wageningen, The Netherlands
| | - A. Grundlehner
- Wageningen University and Research, 6708PB Wageningen, The Netherlands
- Wageningen Marine Research, Wageningen University and Research, 1781AG Den Helder, The Netherlands
| | - S. Brasseur
- NIOZ Royal Netherlands Institute for Sea Research, 1790AB Den Burg, The Netherlands
- Wageningen Marine Research, Wageningen University and Research, 1781AG Den Helder, The Netherlands
| | - B. Kellenberger
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA
| | - D. Tuia
- Ecole Polytechnique Fédérale de Lausanne (EPFL), 1950 Sion, Switzerland
| | - G. Aarts
- NIOZ Royal Netherlands Institute for Sea Research, 1790AB Den Burg, The Netherlands
- Wageningen University and Research, 6708PB Wageningen, The Netherlands
- Wageningen Marine Research, Wageningen University and Research, 1781AG Den Helder, The Netherlands
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11
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Rushmore J, Beechler BR, Tavalire H, Gorsich EE, Charleston B, Devan‐Song A, Glidden CK, Jolles AE. The heterogeneous herd: Drivers of close-contact variation in African buffalo and implications for pathogen invasion. Ecol Evol 2023; 13:e10447. [PMID: 37621318 PMCID: PMC10445036 DOI: 10.1002/ece3.10447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/28/2023] [Accepted: 08/05/2023] [Indexed: 08/26/2023] Open
Abstract
Many infectious pathogens are shared through social interactions, and examining host connectivity has offered valuable insights for understanding patterns of pathogen transmission across wildlife species. African buffalo are social ungulates and important reservoirs of directly-transmitted pathogens that impact numerous wildlife and livestock species. Here, we analyzed African buffalo social networks to quantify variation in close contacts, examined drivers of contact heterogeneity, and investigated how the observed contact patterns affect pathogen invasion likelihoods for a wild social ungulate. We collected continuous association data using proximity collars and sampled host traits approximately every 2 months during a 15-month study period in Kruger National Park, South Africa. Although the observed herd was well connected, with most individuals contacting each other during each bimonthly interval, our analyses revealed striking heterogeneity in close-contact associations among herd members. Network analysis showed that individual connectivity was stable over time and that individual age, sex, reproductive status, and pairwise genetic relatedness were important predictors of buffalo connectivity. Calves were the most connected members of the herd, and adult males were the least connected. These findings highlight the role susceptible calves may play in the transmission of pathogens within the herd. We also demonstrate that, at time scales relevant to infectious pathogens found in nature, the observed level of connectivity affects pathogen invasion likelihoods for a wide range of infectious periods and transmissibilities. Ultimately, our study identifies key predictors of social connectivity in a social ungulate and illustrates how contact heterogeneity, even within a highly connected herd, can shape pathogen invasion likelihoods.
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Affiliation(s)
- Julie Rushmore
- Carlson College of Veterinary MedicineOregon State UniversityCorvallisOregonUSA
- One Health Institute, School of Veterinary MedicineUniversity of CaliforniaDavisCaliforniaUSA
- EpiCenter for Disease Dynamics, School of Veterinary MedicineUniversity of CaliforniaDavisCaliforniaUSA
| | - Brianna R. Beechler
- Carlson College of Veterinary MedicineOregon State UniversityCorvallisOregonUSA
| | - Hannah Tavalire
- Department of Integrative BiologyOregon State UniversityCorvallisOregonUSA
| | - Erin E. Gorsich
- Department of Integrative BiologyOregon State UniversityCorvallisOregonUSA
- The Zeeman Institute: Systems Biology and Infectious Disease Epidemiology ResearchUniversity of WarwickCoventryUK
- School of Life SciencesUniversity of WarwickCoventryUK
| | | | - Anne Devan‐Song
- Department of Integrative BiologyOregon State UniversityCorvallisOregonUSA
| | | | - Anna E. Jolles
- Carlson College of Veterinary MedicineOregon State UniversityCorvallisOregonUSA
- Department of Integrative BiologyOregon State UniversityCorvallisOregonUSA
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12
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Dos Santos EO, Klain VF, B Manrique S, Rodrigues RO, Dos Santos HF, Sangioni LA, Dasso MG, de Almeida MAB, Dos Santos E, Born LC, Reck J, Botton SDA. Influence of landscape structure on previous exposure to Leptospira spp. and Brucella abortus in free-living neotropical primates from southern Brazil. Am J Primatol 2023; 85:e23472. [PMID: 36814095 DOI: 10.1002/ajp.23472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 01/14/2023] [Accepted: 01/21/2023] [Indexed: 02/24/2023]
Abstract
The environments in which neotropical primates live have been undergoing an intense fragmentation process, constituting a major threat to the species' survival and causing resource scarcity, social isolation, and difficulty in dispersal, leaving populations increasingly vulnerable. Moreover, the proximity of wild environments to anthropized landscapes can change the dynamics of pathogens and the parasite-host-environment relationship, creating conditions that favor exposure to different pathogens. To investigate the previous exposure of free-living primates in Rio Grande do Sul State (RS), southern Brazil, to the bacterial agents Leptospira spp. and Brucella abortus, we investigated agglutinating antibodies against 23 serovars of Leptospira spp. using the microscopic agglutination test and B. abortus acidified antigen test in primate serum samples; 101 samples from primates captured between 2002 and 2016 in different forest fragments were used: 63 Alouatta caraya, 36 Alouatta guariba clamitans, and 02 Sapajus nigritus cucullatus. In addition, the forest remnants where the primates were sampled were characterized in a multiscale approach in radii ranging from 200 to 1400 m to investigate the potential relationship of previous exposure to the agent with the elements that make up the landscape structure. The serological investigation indicated the presence of antibodies for at least one of the 23 serovars of Leptospira spp. in 36.6% (37/101) of the samples analyzed, with titers ranging from 100 to 1600. The most observed serovars were Panama (17.8%), Ballum (5.9%), Butembo (5.9%), Canicola (5.9%), Hardjo (4.9%), and Tarassovi (3.9%); no samples were seropositive for Brucella abortus. Decreased forest cover and edge density were the landscape factors that had a significant relationship with Leptospira spp. exposure, indicating that habitat fragmentation may influence contact with the pathogen. The data generated in this study demonstrate the importance of understanding how changes in landscape structure affect exposure to pathogenic microorganisms of zoonotic relevance. Hence, improving epidemiological research and understanding primates' ecological role in these settings can help improve environmental surveillance and conservation strategies for primate populations in different landscapes.
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Affiliation(s)
- Elisandro O Dos Santos
- Laboratório de Saúde Única, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais da Universidade Federal de Santa Maria (UFSM), Santa Maria, Brazil
| | - Vinícius F Klain
- Laboratório de Primatologia, Escola de Ciências da Saúde e da Vida da Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
| | - Sebastián B Manrique
- Laboratório de Primatologia, Escola de Ciências da Saúde e da Vida da Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Brazil
| | - Rogério O Rodrigues
- Laboratório de Leptospirose do Instituto de Pesquisas Veterinárias Desidério Finamor, Secretaria Estadual de Agricultura, Pecuária e Desenvolvimento Rural, Eldorado do Sul, Brazil
| | - Helton F Dos Santos
- Núcleo de Estudos e Pesquisas em Animais Silvestres, Laboratório Central de Diagnóstico de Patologias Aviárias, Departamento de Medicina Veterinária Preventiva, Universidade Federal de Santa Maria (UFSM), Santa Maria, Brazil
| | - Luís A Sangioni
- Laboratório de Saúde Única, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais da Universidade Federal de Santa Maria (UFSM), Santa Maria, Brazil
| | - Maurício G Dasso
- Laboratório de Leptospirose do Instituto de Pesquisas Veterinárias Desidério Finamor, Secretaria Estadual de Agricultura, Pecuária e Desenvolvimento Rural, Eldorado do Sul, Brazil
| | - Marco A B de Almeida
- Divisão de Vigilância Ambiental em Saúde, Centro Estadual de Vigilância em Saúde, Secretaria de Estado da Saúde, Porto Alegre, Brazil
| | - Edmilson Dos Santos
- Divisão de Vigilância Ambiental em Saúde, Centro Estadual de Vigilância em Saúde, Secretaria de Estado da Saúde, Porto Alegre, Brazil
| | - Lucas C Born
- Divisão de Vigilância Ambiental em Saúde, Centro Estadual de Vigilância em Saúde, Secretaria de Estado da Saúde, Porto Alegre, Brazil
| | - José Reck
- Laboratório de Parasitologia do Instituto de Pesquisas Veterinárias Desidério Finamor, Secretaria Estadual de Agricultura, Pecuária e Desenvolvimento Rural, Eldorado do Sul, Brazil
| | - Sônia de Avila Botton
- Laboratório de Saúde Única, Departamento de Medicina Veterinária Preventiva, Centro de Ciências Rurais da Universidade Federal de Santa Maria (UFSM), Santa Maria, Brazil
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13
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Herrera JP, Moody J, Nunn CL. Predicting primate-parasite associations using exponential random graph models. J Anim Ecol 2023; 92:710-722. [PMID: 36633380 DOI: 10.1111/1365-2656.13883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 12/07/2022] [Indexed: 01/13/2023]
Abstract
Ecological associations between hosts and parasites are influenced by host exposure and susceptibility to parasites, and by parasite traits, such as transmission mode. Advances in network analysis allow us to answer questions about the causes and consequences of traits in ecological networks in ways that could not be addressed in the past. We used a network-based framework (exponential random graph models or ERGMs) to investigate the biogeographic, phylogenetic and ecological characteristics of hosts and parasites that affect the probability of interactions among nonhuman primates and their parasites. Parasites included arthropods, bacteria, fungi, protozoa, viruses and helminths. We investigated existing hypotheses, along with new predictors and an expanded host-parasite database that included 213 primate nodes, 763 parasite nodes and 2319 edges among them. Analyses also investigated phylogenetic relatedness, sampling effort and spatial overlap among hosts. In addition to supporting some previous findings, our ERGM approach demonstrated that more threatened hosts had fewer parasites, and notably, that this effect was independent of hosts also having a smaller geographic range. Despite having fewer parasites, threatened host species shared more parasites with other hosts, consistent with loss of specialist parasites and threat arising from generalist parasites that can be maintained in other, non-threatened hosts. Viruses, protozoa and helminths had broader host ranges than bacteria, or fungi, and parasites that infect non-primates had a higher probability of infecting more primate species. The value of the ERGM approach for investigating the processes structing host-parasite networks provided a more complete view on the biogeographic, phylogenetic and ecological traits that influence parasite species richness and parasite sharing among hosts. The results supported some previous analyses and revealed new associations that warrant future research, thus revealing how hosts and parasites interact to form ecological networks.
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Affiliation(s)
- James P Herrera
- Duke Lemur Center SAVA Conservation, Duke University, Durham, North Carolina, USA
| | - James Moody
- Department of Sociology, Duke University, Durham, North Carolina, USA
| | - Charles L Nunn
- Department of Evolutionary Anthropology, Duke University, Durham, North Carolina, USA.,Duke Global Health Institute, Duke University, Durham, North Carolina, USA
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14
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Adhikari RB, Dhakal MA, Ale PB, Regmi GR, Ghimire TR. Survey on the prevalence of intestinal parasites in domestic cats (Felis catus Linnaeus, 1758) in central Nepal. Vet Med Sci 2023; 9:559-571. [PMID: 36346533 PMCID: PMC10029910 DOI: 10.1002/vms3.999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
INTRODUCTION Cats (Felis catus) are the only felines that live in close contact with humans. Since cats can act as vectors, carriers, reservoirs and definitive hosts of many gastrointestinal (GI) parasites, parasitic assessment could contribute to their survival and well-being. AIMS The current study aimed to assess the diversity and prevalence of GI parasites in domestic and feral cats from Ratnanagar in Chitwan in Central Nepal. METHODS A total of 107 fresh faecal samples of cats (90 household cats and 17 feral cats) of varied ages and sex were collected and transported to the laboratory. The copromicroscopic examination was carried out following direct wet mount, formalin-ethyl acetate sedimentation, saturated salt flotation, acid-fast staining and sporulation techniques. Furthermore, associated risk factors were evaluated to ascertain the predictor of risks for parasitic acquisition. RESULTS The current study revealed an overall 95.3% prevalence rate with a 100% rate in feral cats and 94.4% in household cats. Altogether, 18 (17 known and one unknown) different species of GI parasites were reported with the helminths (95.3%; 11 species) and the protozoa (55.1%; seven species). Besides age and sex, outdoor lifestyle, absence or unknown history of medication and hunting behaviour of the felines are the predictors of risk. Furthermore, mixed infection was comparatively higher than single infection in the faecal samples. CONCLUSIONS Cats harbour a higher prevalence and greater diversity of GI parasites, and parasitism varies with age and sex. This finding can be essential for veterinarians and public health authorities for strategic treatment and for assessing the zoonotic transmission of the parasites from these felines. Importantly, an effective medication strategy for cats and owners is recommended.
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Affiliation(s)
- Roshan Babu Adhikari
- Third Pole Conservancy, Bhaktapur, Nepal
- Nepalese Army Institute of Health Sciences (NAIHS), Kathmandu, Nepal
| | | | | | | | - Tirth Raj Ghimire
- Department of Zoology, Tri-Chandra Multiple Campus, Tribhuvan University, Kathmandu, Nepal
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15
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Rabies transmission in the Arctic: An agent-based model reveals the effects of broad-scale movement strategies on contact risk between Arctic foxes. Ecol Modell 2023. [DOI: 10.1016/j.ecolmodel.2022.110207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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16
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Zhu P, Liu W, Zhang X, Li M, Liu G, Yu Y, Li Z, Li X, Du J, Wang X, Grueter CC, Li M, Zhou X. Correlated evolution of social organization and lifespan in mammals. Nat Commun 2023; 14:372. [PMID: 36720880 PMCID: PMC9889386 DOI: 10.1038/s41467-023-35869-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 01/05/2023] [Indexed: 02/02/2023] Open
Abstract
Discerning the relationship between sociality and longevity would permit a deeper understanding of how animal life history evolved. Here, we perform a phylogenetic comparative analysis of ~1000 mammalian species on three states of social organization (solitary, pair-living, and group-living) and longevity. We show that group-living species generally live longer than solitary species, and that the transition rate from a short-lived state to a long-lived state is higher in group-living than non-group-living species, altogether supporting the correlated evolution of social organization and longevity. The comparative brain transcriptomes of 94 mammalian species identify 31 genes, hormones and immunity-related pathways broadly involved in the association between social organization and longevity. Further selection features reveal twenty overlapping pathways under selection for both social organization and longevity. These results underscore a molecular basis for the influence of the social organization on longevity.
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Affiliation(s)
- Pingfen Zhu
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China
| | - Weiqiang Liu
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiaoxiao Zhang
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Meng Li
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China
| | - Gaoming Liu
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China
| | - Yang Yu
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China.,Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, 230026, China
| | - Zihao Li
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuanjing Li
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Juan Du
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiao Wang
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China
| | - Cyril C Grueter
- School of Human Sciences, The University of Western Australia, Perth, WA, 6009, Australia.,Centre for Evolutionary Biology, School of Biological Sciences, The University of Western Australia, Perth, WA, 6009, Australia.,International Center of Biodiversity and Primate Conservation, Dali University, Dali, Yunnan, 671003, China
| | - Ming Li
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China. .,Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, 650223, China.
| | - Xuming Zhou
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Beijing, 100101, China.
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17
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Nordli K, Wabakken P, Eriksen A, Sand H, Wikenros C, Maartmann E, Zimmermann B. Spatial and temporal cohesion of parents and offspring in a social large carnivore. Anim Behav 2023. [DOI: 10.1016/j.anbehav.2022.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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18
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Pilakouta N, O'Donnell PJ, Crespel A, Levet M, Claireaux M, Humble JL, Kristjánsson BK, Skúlason S, Lindström J, Metcalfe NB, Killen SS, Parsons KJ. A warmer environment can reduce sociability in an ectotherm. GLOBAL CHANGE BIOLOGY 2023; 29:206-214. [PMID: 36259414 PMCID: PMC10092372 DOI: 10.1111/gcb.16451] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 08/15/2022] [Accepted: 09/25/2022] [Indexed: 05/05/2023]
Abstract
The costs and benefits of being social vary with environmental conditions, so individuals must weigh the balance between these trade-offs in response to changes in the environment. Temperature is a salient environmental factor that may play a key role in altering the costs and benefits of sociality through its effects on food availability, predator abundance, and other ecological parameters. In ectotherms, changes in temperature also have direct effects on physiological traits linked to social behaviour, such as metabolic rate and locomotor performance. In light of climate change, it is therefore important to understand the potential effects of temperature on sociality. Here, we took the advantage of a 'natural experiment' of threespine sticklebacks from contrasting thermal environments in Iceland: geothermally warmed water bodies (warm habitats) and adjacent ambient-temperature water bodies (cold habitats) that were either linked (sympatric) or physically distinct (allopatric). We first measured the sociability of wild-caught adult fish from warm and cold habitats after acclimation to a low and a high temperature. At both acclimation temperatures, fish from the allopatric warm habitat were less social than those from the allopatric cold habitat, whereas fish from sympatric warm and cold habitats showed no differences in sociability. To determine whether differences in sociability between thermal habitats in the allopatric population were heritable, we used a common garden breeding design where individuals from the warm and the cold habitat were reared at a low or high temperature for two generations. We found that sociability was indeed heritable but also influenced by rearing temperature, suggesting that thermal conditions during early life can play an important role in influencing social behaviour in adulthood. By providing the first evidence for a causal effect of rearing temperature on social behaviour, our study provides novel insights into how a warming world may influence sociality in animal populations.
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Affiliation(s)
- Natalie Pilakouta
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
- School of Biological SciencesUniversity of AberdeenAberdeenUK
| | - Patrick J. O'Donnell
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
| | - Amélie Crespel
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
- Department of BiologyUniversity of TurkuTurkuFinland
| | - Marie Levet
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
- Department of Biological SciencesUniversity of MontrealMontrealCanada
| | - Marion Claireaux
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
- Norwegian Institute of Marine ResearchBergenNorway
| | - Joseph L. Humble
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
| | | | - Skúli Skúlason
- Department of Aquaculture and Fish BiologyHólar UniversitySauðárkrókurIceland
- Icelandic Museum of Natural HistoryReykjavíkIceland
| | - Jan Lindström
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
| | - Neil B. Metcalfe
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
| | - Shaun S. Killen
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
| | - Kevin J. Parsons
- School of Biodiversity, One Health and Veterinary MedicineUniversity of GlasgowGlasgowUK
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19
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Xu Z, MacIntosh AJ, Castellano-Navarro A, Macanás-Martínez E, Suzumura T, Duboscq J. Linking parasitism to network centrality and the impact of sampling bias in its interpretation. PeerJ 2022; 10:e14305. [PMID: 36420133 PMCID: PMC9677876 DOI: 10.7717/peerj.14305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 10/05/2022] [Indexed: 11/19/2022] Open
Abstract
Group living is beneficial for individuals, but also comes with costs. One such cost is the increased possibility of pathogen transmission because increased numbers or frequencies of social contacts are often associated with increased parasite abundance or diversity. The social structure of a group or population is paramount to patterns of infection and transmission. Yet, for various reasons, studies investigating the links between sociality and parasitism in animals, especially in primates, have only accounted for parts of the group (e.g., only adults), which is likely to impact the interpretation of results. Here, we investigated the relationship between social network centrality and an estimate of gastrointestinal helminth infection intensity in a whole group of Japanese macaques (Macaca fuscata). We then tested the impact of omitting parts of the group on this relationship. We aimed to test: (1) whether social network centrality -in terms of the number of partners (degree), frequency of interactions (strength), and level of social integration (eigenvector) -was linked to parasite infection intensity (estimated by eggs per gram of faeces, EPG); and, (2) to what extent excluding portions of individuals within the group might influence the observed relationship. We conducted social network analysis on data collected from one group of Japanese macaques over three months on Koshima Island, Japan. We then ran a series of knock-out simulations. General linear mixed models showed that, at the whole-group level, network centrality was positively associated with geohelminth infection intensity. However, in partial networks with only adult females, only juveniles, or random subsets of the group, the strength of this relationship - albeit still generally positive - lost statistical significance. Furthermore, knock-out simulations where individuals were removed but network metrics were retained from the original whole-group network showed that these changes are partly a power issue and partly an effect of sampling the incomplete network. Our study indicates that sampling bias can thus hamper our ability to detect real network effects involving social interaction and parasitism. In addition to supporting earlier results linking geohelminth infection to Japanese macaque social networks, this work introduces important methodological considerations for research into the dynamics of social transmission, with implications for infectious disease epidemiology, population management, and health interventions.
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Affiliation(s)
- Zhihong Xu
- Wildlife Research Center, Kyoto University, Kyoto, Kyoto, Japan,Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| | - Andrew J.J. MacIntosh
- Wildlife Research Center, Kyoto University, Kyoto, Kyoto, Japan,Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan
| | - Alba Castellano-Navarro
- Ethology and Animal Welfare Section, Universidad CEU Cardenal Herrera, Valencia, Valencia, Spain,Institute of Biology, Universität Leipzig, Leipzig, Saxony, Germany
| | - Emilio Macanás-Martínez
- Ethology and Animal Welfare Section, Universidad CEU Cardenal Herrera, Valencia, Valencia, Spain,Institute of Biology, Universität Leipzig, Leipzig, Saxony, Germany
| | | | - Julie Duboscq
- UMR7206 Eco-Anthropologie, CNRS-MNHN-Université de Paris, Paris, Île-de-France, France,Department of Behavioural Ecology, Johann-Friedrich-Blumenbach Institute for Zoology and Anthropology, University of Göttingen, Göttingen, Lower Saxony, Germany
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20
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Johnson KVA, Watson KK, Dunbar RIM, Burnet PWJ. Sociability in a non-captive macaque population is associated with beneficial gut bacteria. Front Microbiol 2022; 13:1032495. [PMID: 36439813 PMCID: PMC9691693 DOI: 10.3389/fmicb.2022.1032495] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 10/03/2022] [Indexed: 11/12/2022] Open
Abstract
The relationship between social behaviour and the microbiome is known to be reciprocal. Research in wild animal populations, particularly in primate social groups, has revealed the role that social interactions play in microbial transmission, whilst studies in laboratory animals have demonstrated that the gut microbiome can affect multiple aspects of behaviour, including social behaviour. Here we explore behavioural variation in a non-captive animal population with respect to the abundance of specific bacterial genera. Social behaviour based on grooming interactions is assessed in a population of rhesus macaques (Macaca mulatta), and combined with gut microbiome data. We focus our analyses on microbiome genera previously linked to sociability and autistic behaviours in rodents and humans. We show in this macaque population that some of these genera are also related to an individual's propensity to engage in social interactions. Interestingly, we find that several of the genera positively related to sociability, such as Faecalibacterium, are well known for their beneficial effects on health and their anti-inflammatory properties. In contrast, the genus Streptococcus, which includes pathogenic species, is more abundant in less sociable macaques. Our results indicate that microorganisms whose abundance varies with individual social behaviour also have functional links to host immune status. Overall, these findings highlight the connections between social behaviour, microbiome composition, and health in an animal population.
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Affiliation(s)
- Katerina V.-A. Johnson
- Department of Psychiatry, University of Oxford, Oxford, United Kingdom,Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom,*Correspondence: Katerina V.-A. Johnson,
| | - Karli K. Watson
- Institute of Cognitive Science, University of Colorado Boulder, Boulder, CO, United States
| | - Robin I. M. Dunbar
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
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21
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Mongkol N, Wang FS, Suthisawat S, Likhit O, Charoen P, Boonnak K. Seroprevalence of Chikungunya and Zika virus in nonhuman primates: A systematic review and meta-analysis. One Health 2022; 15:100455. [DOI: 10.1016/j.onehlt.2022.100455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/26/2022] [Accepted: 11/03/2022] [Indexed: 11/06/2022] Open
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22
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Gago H, Ruiz-Fons F, Drechsler RM, Alambiaga I, Monrós JS. Patterns of adult tick parasitization of coexisting European (Erinaceus europaeus) and Algerian (Atelerix algirus) hedgehog populations in eastern Iberia. Ticks Tick Borne Dis 2022; 13:102048. [PMID: 36183586 DOI: 10.1016/j.ttbdis.2022.102048] [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: 03/29/2022] [Revised: 09/21/2022] [Accepted: 09/21/2022] [Indexed: 11/28/2022]
Abstract
The availability of data regarding population abundance and dynamics of ticks in wild vertebrate populations is crucial to understand the host-tick relationship and to assess the risk for domestic animals and humans from possible zoonotic diseases. In this study we analyse several host-intrinsic and environmental factors affecting the tick population of two sympatric hedgehog species (the European and the Algerian hedgehog) in two differently anthropized habitats in eastern Spain. We captured 215 hedgehogs and sampled 356 adult ticks of four different species (Rhipicephalus sanguineus, R. turanicus, R. bursa and R. pusillus). We analysed by General Linear Mixed Models how the hosts' species, sex, capture month and site and their interactions affected tick presence and tick load. Further, we carried out Spearman correlation tests to analyse how environmental temperature and precipitation affect tick presence and load on hedgehogs. We found that, in general, male hedgehogs were more infested than females. However, the effects of the different factors depended on the tick species, especially related to their endophilic or exophilic character. High values of general tick infestation can be explained by the coincidence of tick activity peaks and higher male host activity levels, especially within areas with higher habitat diversity and species richness. We also discuss how the potential immunosuppressive effect of testosterone could be affecting our results. Our results show that in highly anthropized environments hedgehogs potentially act as important mixing vessels for tick-borne zoonotic pathogens and that monitoring ticks in periurban wildlife is important to assess potential health risks for pets and humans.
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Affiliation(s)
- Héctor Gago
- Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, c/Catedrático José Beltrán Martínez 2, 46980 Paterna, Valencia, Spain.
| | - Francisco Ruiz-Fons
- Health and Biotechnology (SaBio) group, Instituto de Investigación en Recursos Cinegéticos IREC (CSIC-UCLM-JCCM), Ciudad Real, Spain
| | - Robby M Drechsler
- Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, c/Catedrático José Beltrán Martínez 2, 46980 Paterna, Valencia, Spain
| | - Iván Alambiaga
- Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, c/Catedrático José Beltrán Martínez 2, 46980 Paterna, Valencia, Spain
| | - Juan S Monrós
- Cavanilles Institute of Biodiversity and Evolutionary Biology, University of Valencia, c/Catedrático José Beltrán Martínez 2, 46980 Paterna, Valencia, Spain
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23
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Pinacho-Guendulain B, Montiel-Castro AJ, Ramos-Fernández G, Pacheco-López G. Social complexity as a driving force of gut microbiota exchange among conspecific hosts in non-human primates. Front Integr Neurosci 2022; 16:876849. [PMID: 36110388 PMCID: PMC9468716 DOI: 10.3389/fnint.2022.876849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 05/16/2022] [Indexed: 11/13/2022] Open
Abstract
The emergent concept of the social microbiome implies a view of a highly connected biological world, in which microbial interchange across organisms may be influenced by social and ecological connections occurring at different levels of biological organization. We explore this idea reviewing evidence of whether increasing social complexity in primate societies is associated with both higher diversity and greater similarity in the composition of the gut microbiota. By proposing a series of predictions regarding such relationship, we evaluate the existence of a link between gut microbiota and primate social behavior. Overall, we find that enough empirical evidence already supports these predictions. Nonetheless, we conclude that studies with the necessary, sufficient, explicit, and available evidence are still scarce. Therefore, we reflect on the benefit of founding future analyses on the utility of social complexity as a theoretical framework.
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Affiliation(s)
- Braulio Pinacho-Guendulain
- Doctorado en Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana (UAM), Ciudad de México, Mexico
| | - Augusto Jacobo Montiel-Castro
- Department of Health Sciences, Metropolitan Autonomous University (UAM), Lerma, Mexico
- *Correspondence: Augusto Jacobo Montiel-Castro,
| | - Gabriel Ramos-Fernández
- Institute for Research on Applied Mathematics and Systems (IIMAS), National Autonomous University of Mexico (UNAM), Mexico City, Mexico
- Center for Complexity Sciences, National Autonomous University of Mexico, Mexico City, Mexico
| | - Gustavo Pacheco-López
- Department of Health Sciences, Metropolitan Autonomous University (UAM), Lerma, Mexico
- Gustavo Pacheco-López,
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Drivers of the Ectoparasite Community and Co-Infection Patterns in Rural and Urban Burrowing Owls. BIOLOGY 2022; 11:biology11081141. [PMID: 36009768 PMCID: PMC9405203 DOI: 10.3390/biology11081141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 07/19/2022] [Accepted: 07/26/2022] [Indexed: 11/24/2022]
Abstract
Simple Summary We analyzed the ectoparasite community of a monomorphic and non-social bird, the burrowing owl, Athene cunicularia, breeding in rural and urban habitats. Such community was composed by two lice, one mite and one flea species. Rural individuals had more fleas and less mites than urban ones. Adult birds harbored less ectoparasites than young ones and females harbored more lice than males. The presence of lice was positively related to the presence of fleas. On the contrary, the presence of mites was negatively related to the presence of fleas and lice. The study of parasite communities in urban and rural populations of the same species can shed light on how urban stressor factors impact the physiology of wildlife inhabiting cities and, therefore, the host-parasite relationships. Abstract Urbanization creates new ecological conditions that can affect biodiversity at all levels, including the diversity and prevalence of parasites of species that may occupy these environments. However, few studies have compared bird–ectoparasite interactions between urban and rural individuals. Here, we analyze the ectoparasite community and co-infection patterns of urban and rural burrowing owls, Athene cunicularia, to assess the influence of host traits (i.e., sex, age, and weight), and environmental factors (i.e., number of conspecifics per nest, habitat type and aridity) on its composition. Ectoparasites of burrowing owls included two lice, one flea, and one mite. The overall prevalence for mites, lice and fleas was 1.75%, 8.76% and 3.50%, respectively. A clear pattern of co-infection was detected between mites and fleas and, to less extent, between mites and lice. Adult owls harbored fewer ectoparasites than nestlings, and adult females harbored more lice than males. Our results also show that mite and flea numbers were higher when more conspecifics cohabited the same burrow, while lice showed the opposite pattern. Rural individuals showed higher flea parasitism and lower mite parasitism than urban birds. Moreover, mite numbers were negatively correlated with aridity and host weight. Although the ectoparasitic load of burrowing owls appears to be influenced by individual age, sex, number of conspecifics per nest, and habitat characteristics, the pattern of co-infection found among ectoparasites could also be mediated by unexplored factors such as host immune response, which deserves further research.
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Odewahn R, Wright BR, Czirják GÁ, Higgins DP. Differences in constitutive innate immunity between divergent Australian marsupials. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2022; 132:104399. [PMID: 35307478 DOI: 10.1016/j.dci.2022.104399] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 06/14/2023]
Abstract
Understanding immunity in wildlife populations is important from both One Health and conservation perspectives. The constitutive innate immune system is the first line of defence against pathogens, and comparisons among taxa can test the impact of evolution and life history on immune function. We investigated serum bacterial killing ability (BKA) of five marsupial species that employ varying life history strategies, demonstrated to influence immunity in other vertebrates. The brushtail possum and eastern grey kangaroo had the greatest BKA, while ringtail possums and koalas had the least. These differences were independent of social structure, captivity status and phylogeny, but were associated with diet and body size. Sex and disease status had no effect on BKA in koalas, however potential for differences between wild and captive koalas warrants further investigation. The current study has provided a foundation for future investigations into how adaptive and innate immunity interact in marsupials from an eco-evolutionary perspective.
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Affiliation(s)
- Rebecca Odewahn
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW, Australia
| | - Belinda R Wright
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW, Australia
| | - Gábor Á Czirják
- Department of Wildlife Diseases, Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Straße 17, 10315, Berlin, Germany
| | - Damien P Higgins
- Sydney School of Veterinary Science, Faculty of Science, University of Sydney, NSW, Australia.
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Lynsdale CL, Seltmann MW, Mon NO, Aung HH, Nyein UK, Htut W, Lahdenperä M, Lummaa V. Investigating associations between nematode infection and three measures of sociality in Asian elephants. Behav Ecol Sociobiol 2022; 76:87. [PMID: 35765658 PMCID: PMC9232411 DOI: 10.1007/s00265-022-03192-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 06/05/2022] [Accepted: 06/07/2022] [Indexed: 12/19/2022]
Abstract
Abstract
Frequent social interactions, proximity to conspecifics, and group density are main drivers of infections and parasite transmissions. However, recent theoretical and empirical studies suggest that the health benefits of sociality and group living can outweigh the costs of infection and help social individuals fight infections or increase their infection-related tolerance level. Here, we combine the advantage of studying artificially created social work groups with different demographic compositions with free-range feeding and social behaviours in semi-captive Asian elephants (Elephas maximus), employed in timber logging in Myanmar. We examine the link between gastro-intestinal nematode load (strongyles and Strongyloides spp.), estimated by faecal egg counts, and three different aspects of an elephant’s social world: individual solitary behaviour, work group size, and work group sex ratio. Controlling for sex, age, origin, time since last deworming treatment, year, human sampler bias, and individual identity, we found that infection by nematodes ranged from 0 to 2720 eggs/g between and within 26 male and 45 female elephants over the 4-year study period. However, such variation was not linked to any investigated measures of sociality in either males or females. Our findings highlight the need for finer-scale studies, establishing how sociality is limited by, mitigates, or protects against infection in different ecological contexts, to fully understand the mechanisms underlying these pathways. Significance statement Being social involves not only benefits, such as improved health, but also costs, including increased risk of parasitism and infectious disease. We studied the relationship between and three different sociality measures—solitary behaviour, group size, and the proportion of females to males within a group—and infection by gut nematodes (roundworms), using a unique study system of semi-captive working Asian elephants. Our system allows for observing how infection is linked to sociality measures across different social frameworks. We found that none of our social measures was associated with nematode infection in the studied elephants. Our results therefore suggest that here infection is not a large cost to group living, that it can be alleviated by the benefits of increased sociality, or that there are weak infection–sociality associations present which could not be captured and thus require finer-scale measures than those studied here. Overall, more studies are needed from a diverse range of systems that investigate specific aspects of social infection dynamics.
Supplementary Information The online version contains supplementary material available at 10.1007/s00265-022-03192-8.
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Affiliation(s)
- Carly L. Lynsdale
- Natural Resources Institute, Helsinki, Finland
- Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
- Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | | | - Nay Oo Mon
- Department of Animal Science, University of Veterinary Science, Yezin, Myanmar
| | - Htoo Htoo Aung
- Myanma Timber Enterprise, Ministry of Natural Resources and Environmental Conservation, Yangon, Myanmar
| | - UKyaw Nyein
- Myanma Timber Enterprise, Ministry of Natural Resources and Environmental Conservation, Yangon, Myanmar
| | - Win Htut
- Myanma Timber Enterprise, Ministry of Natural Resources and Environmental Conservation, Yangon, Myanmar
| | - Mirkka Lahdenperä
- Department of Public Health, University of Turku and Turku University Hospital, 20014 Turku, Finland
- Centre for Population Health Research, University of Turku and Turku University Hospital, 20014 Turku, Finland
| | - Virpi Lummaa
- Department of Biology, University of Turku, 20014 Turku, Finland
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Shanebeck KM, Besson AA, Lagrue C, Green SJ. The energetic costs of sub-lethal helminth parasites in mammals: a meta-analysis. Biol Rev Camb Philos Soc 2022; 97:1886-1907. [PMID: 35678252 DOI: 10.1111/brv.12867] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 05/02/2022] [Accepted: 05/05/2022] [Indexed: 01/07/2023]
Abstract
Parasites, by definition, have a negative effect on their host. However, in wild mammal health and conservation research, sub-lethal infections are commonly assumed to have negligible health effects unless parasites are present in overwhelming numbers. Here, we propose a definition for host health in mammals that includes sub-lethal effects of parasites on the host's capacity to adapt to the environment and maintain homeostasis. We synthesized the growing number of studies on helminth parasites in mammals to assess evidence for the relative magnitude of sub-lethal effects of infection across mammal taxa based on this expanded definition. Specifically, we develop and apply a framework for organizing disparate metrics of parasite effects on host health and body condition according to their impact on an animal's energetic condition, defined as the energetic burden of pathogens on host physiological and behavioural functions that relate directly to fitness. Applying this framework within a global meta-analysis of helminth parasites in wild, laboratory and domestic mammal hosts produced 142 peer-reviewed studies documenting 599 infection-condition effects. Analysing these data within a multiple working hypotheses framework allowed us to evaluate the relative weighted contribution of methodological (study design, sampling protocol, parasite quantification methods) and biological (phylogenetic relationships and host/parasite life history) moderators to variation in the magnitude of health effects. We found consistently strong negative effects of infection on host energetic condition across taxonomic groups, with unusually low heterogeneity in effect sizes when compared with other ecological meta-analyses. Observed effect size was significantly lower within cross-sectional studies (i.e. observational studies that investigated a sub-set of a population at a single point in time), the most prevalent methodology. Furthermore, opportunistic sampling led to a weaker negative effect compared to proactive sampling. In the model of host taxonomic group, the effect of infection on energetic condition in carnivores was not significant. However, when sampling method was included, it explained substantial inter-study variance; proactive sampling showing a strongly significant negative effect while opportunistic sampling detected only a weak, non-significant effect. This may partly underlie previous assumptions that sub-lethal parasites do not have significant effects on host health. We recommend future studies adopt energetic condition as the framework for assessing parasite effects on wildlife health and provide guidelines for the selection of research protocols, health proxies, and relating infection to fitness.
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Affiliation(s)
- Kyle M Shanebeck
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, Alberta, Canada
| | - Anne A Besson
- Department of Zoology, University of Otago, 340 Great King Street, Dunedin, 9016, New Zealand
| | - Clement Lagrue
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, Alberta, Canada.,Department of Zoology, University of Otago, 340 Great King Street, Dunedin, 9016, New Zealand.,Department of Conservation, 265 Princes Street, Dunedin, 9016, New Zealand
| | - Stephanie J Green
- Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, Alberta, Canada
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Lutermann H. Socializing in an Infectious World: The Role of Parasites in Social Evolution of a Unique Rodent Family. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.879031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Transmission of parasites between hosts is facilitated by close contact of hosts. Consequently, parasites have been proposed as an important constraint to the evolution of sociality accounting for its rarity. Despite the presumed costs associated with parasitism, the majority of species of African mole-rats (Family: Bathyergidae) are social. In fact, only the extremes of sociality (i.e., solitary and singular breeding) are represented in this subterranean rodent family. But how did bathyergids overcome the costs of parasitism? Parasite burden is a function of the exposure and susceptibility of a host to parasites. In this review I explore how living in sealed burrow systems and the group defenses that can be employed by closely related group members can effectively reduce the exposure and susceptibility of social bathyergids to parasites. Evidence suggests that this can be achieved largely by investment in relatively cheap and flexible behavioral rather than physiological defense mechanisms. This also shifts the selection pressure for parasites on successful transmission between group members rather than transmission between groups. In turn, this constrains the evolution of virulence and favors socially transmitted parasites (e.g., mites and lice) further reducing the costs of parasitism for social Bathyergidae. I conclude by highlighting directions for future research to evaluate the mechanisms proposed and to consider parasites as facilitators of social evolution not only in this rodent family but also other singular breeders.
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Detrain C, Leclerc JB. Spatial distancing by fungus-exposed Myrmica ants is prompted by sickness rather than contagiousness. JOURNAL OF INSECT PHYSIOLOGY 2022; 139:104384. [PMID: 35318040 DOI: 10.1016/j.jinsphys.2022.104384] [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: 10/06/2021] [Revised: 02/24/2022] [Accepted: 03/16/2022] [Indexed: 06/14/2023]
Abstract
The ecological success of ants relies on their high level of sociality and cooperation between genetically related nestmates. However, these group-living insects suffer from elevated risks of disease outbreak in the whole nest. To face this sanitary challenge, social and spatial distancing of pathogen-exposed individuals from susceptible nestmates appear to be simple, although efficient, ways to limit the propagation of contact-transmitted pathogens. Here we question whether spatial distancing in Myrmica rubra ants is an active response of diseased individuals that correlates with their level of infectiousness. We contaminated foragers with spores of Metarhizium brunneum entomopathogenic fungus. We daily tracked the location of these pathogen-exposed individuals and we analyzed their movement patterns until their death on the 5th day post-contamination. Quite unexpectedly, we found that contagious individuals, whose body was covered with infectious spores, did not reduce their mobility nor stayed far away from larvae in order to limit pathogen transmission to healthy nestmates. Spatial distancing occurred later when diseased individuals were no longer contagious because spores had penetrated their body. These sick ants mainly stayed outside the nest, were less mobile and showed a shift from a superdiffusive to subdiffusive walking pattern. Furthermore, these diseased ants did not actively head towards directions that were opposite to the nest entrance. This study found no evidence for early spatial distancing by contaminated M.rubra workers that would fit to the actual risk of colony-wide contagion. Coupled to a lower mobility and area-reduced walking patterns, the late distancing of moribund individuals appears to be a symptom of sickness resulting from fungus-induced physical and physiological dysfunctions. Besides questioning the truly altruistic nature of death in isolation in this system (and potentially others), we discuss about the ecological and physiological constraints that explain the absence of early distancing when some ant species are exposed to pathogens.
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Affiliation(s)
- Claire Detrain
- Unit of Social Ecology CP 231, Université Libre de Bruxelles, 50 Avenue F Roosevelt, 1050 Brussels, Belgium.
| | - Jean-Baptiste Leclerc
- Unit of Social Ecology CP 231, Université Libre de Bruxelles, 50 Avenue F Roosevelt, 1050 Brussels, Belgium
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30
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Tepox-Vivar N, Stephenson JF, Guevara-Fiore P. Transmission dynamics of ectoparasitic gyrodactylids (Platyhelminthes, Monogenea): An integrative review. Parasitology 2022; 149:1-13. [PMID: 35481457 DOI: 10.1017/s0031182022000361] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Parasite transmission is the ability of pathogens to move between hosts. As a key component of the interaction between hosts and parasites, it has crucial implications for the fitness of both. Here, we review the transmission dynamics of Gyrodactylus species, which are monogenean ectoparasites of teleost fishes and a prominent model for studies of parasite transmission. Particularly, we focus on the most studied host–parasite system within this genus: guppies, Poecilia reticulata, and G. turnbulli/G. bullatarudis. Through an integrative literature examination, we identify the main variables affecting Gyrodactylus spread between hosts, and the potential factors that enhance their transmission. Previous research indicates that Gyrodactylids spread when their current conditions are unsuitable. Transmission depends on abiotic factors like temperature, and biotic variables such as gyrodactylid biology, host heterogeneity, and their interaction. Variation in the degree of social contact between hosts and sexes might also result in distinct dynamics. Our review highlights a lack of mathematical models that could help predict the dynamics of gyrodactylids, and there is also a bias to study only a few species. Future research may usefully focus on how gyrodactylid reproductive traits and host heterogeneity promote transmission and should incorporate the feedbacks between host behaviour and parasite transmission.
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Affiliation(s)
- Natalia Tepox-Vivar
- Maestría en Ciencias Biológicas, Benemérita Universidad Autónoma de Puebla (BUAP), Puebla 72592, Mexico
| | - Jessica F Stephenson
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Palestina Guevara-Fiore
- Facultad de Ciencias Biológicas, Benemérita Universidad Autónoma de Puebla (BUAP), Puebla 72592, Mexico
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Alaidrous W, Villa SM, de Roode JC, Majewska AA. Crowding does not affect monarch butterflies’ resistance to a protozoan parasite. Ecol Evol 2022; 12:e8791. [PMID: 35414899 PMCID: PMC8986514 DOI: 10.1002/ece3.8791] [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: 11/30/2021] [Revised: 03/08/2022] [Accepted: 03/14/2022] [Indexed: 11/12/2022] Open
Abstract
Host density is an important factor when it comes to parasite transmission and host resistance. Increased host density can increase contact rate between individuals and thus parasite transmission. Host density can also cause physiological changes in the host, which can affect host resistance. Yet, the direction in which host density affects host resistance remains unresolved. It is also unclear whether food limitation plays a role in this effect. We investigated the effect of larval density in monarch butterflies, Danaus plexippus, on the resistance to their natural protozoan parasite Ophryocystis elektroscirrha under both unlimited and limited food conditions. We exposed monarchs to various density treatments as larvae to mimic high densities observed in sedentary populations. Data on infection and parasite spore load were collected as well as development time, survival, wing size, and melanization. Disease susceptibility under either food condition or across density treatments was similar. However, we found high larval density impacted development time, adult survival, and wing morphology when food was limited. This study aids our understanding of the dynamics of environmental parasite transmission in monarch populations, which can help explain the increased prevalence of parasites in sedentary monarch populations compared to migratory populations.
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Affiliation(s)
- Wajd Alaidrous
- Department of Biology Emory University Atlanta Georgia USA
- Division of Biological and Environmental Science and Engineering (BESE) King Abdullah University for Science and Technology Thuwal Saudi Arabia
| | - Scott M. Villa
- Department of Biology Emory University Atlanta Georgia USA
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Tombak KJ, Easterling LA, Martinez L, Seng MS, Wait LF, Rubenstein DI. Divergent water requirements partition exposure risk to parasites in wild equids. Ecol Evol 2022; 12:e8693. [PMID: 35342568 PMCID: PMC8928873 DOI: 10.1002/ece3.8693] [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: 07/01/2021] [Revised: 01/22/2022] [Accepted: 01/28/2022] [Indexed: 11/16/2022] Open
Abstract
For grazing herbivores, dung density in feeding areas is an important determinant of exposure risk to fecal‐orally transmitted parasites. When host species share the same parasite species, a nonrandom distribution of their cumulative dung density and/or nonrandom ranging and feeding behavior may skew exposure risk and the relative selection pressure parasites impose on each host. The arid‐adapted Grevy's zebra (Equus grevyi) can range more widely than the water‐dependent plains zebra (Equus quagga), with which it shares the same species of gastrointestinal nematodes. We studied how the spatial distribution of zebra dung relates to ranging and feeding behavior to assess parasite exposure risk in Grevy's and plains zebras at a site inhabited by both zebra species. We found that zebra dung density declined with distance from water, Grevy's zebra home ranges (excluding those of territorial males) were farther from water than those of plains zebras, and plains zebra grazing areas had higher dung density than random points while Grevy's zebra grazing areas did not, suggesting a greater exposure risk in plains zebras associated with their water dependence. Fecal egg counts increased with home range proximity to water for both species, but the response was stronger in plains zebras, indicating that this host species may be particularly vulnerable to the elevated exposure risk close to water. We further ran experiments on microclimatic effects on dung infectivity and showed that fewer nematode eggs embryonated in dung in the sun than in the shade. However, only 5% of the zebra dung on the landscape was in shade, indicating that the microclimatic effects of shade on the density of infective larvae is not a major influence on exposure risk dynamics. Ranging constraints based on water requirements appear to be key mediators of nematode parasite exposure in free‐ranging equids.
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Affiliation(s)
- Kaia J. Tombak
- Department of Anthropology Hunter College of the City University of New York New York New York USA
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey USA
| | - Laurel A. Easterling
- School of Veterinary Medicine University of Pennsylvania Philadelphia Pennsylvania USA
| | | | | | - Liana F. Wait
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey USA
| | - Daniel I. Rubenstein
- Department of Ecology and Evolutionary Biology Princeton University Princeton New Jersey USA
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Figuerêdo Duarte Moraes M, de Souza Pollo A, Lux Hoppe EG. Filarids (Spirurida: Onchocercidae) in wild carnivores and domestic dogs from the Brazilian Atlantic forest. PLoS Negl Trop Dis 2022; 16:e0010213. [PMID: 35259155 PMCID: PMC8903299 DOI: 10.1371/journal.pntd.0010213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 01/27/2022] [Indexed: 12/05/2022] Open
Abstract
Onchocercidae nematodes are heteroxenous parasites with worldwide distribution, and some of the species associated to animals may present zoonotic potential. Climatic changes and anthropic influences on the environment may result in vectors’ proliferation, facilitating the spillover to humans and/or non-typical animal hosts. The Iguaçu National Park (PARNA Iguaçu), one of the most important Brazilian natural remanescents of Atlantic rainforest, is strongly affected by human activities such as tourism and agriculture. The complexity of this area is especially characterized by the close nexus between the rich wildlife, humans, and domestic animals, especially domestic dogs. Based on this, this research aimed to diagnose the Onchocercidae nematodes in wild carnivores and domestic dogs in the PARNA Iguaçu and the surrounding areas. For this, we collected 162 samples of seven species of wild carnivores and 225 samples of domestic dogs. The presence of microfilariae in the blood samples was diagnosed by the modified Knott’s test and molecular screening, and the specific identification was based on sequencing of the myoHC and hsp70 genes. Microfilariae were detected only in ring-tailed coatis, in which we found five species: Mansonella sp. 1, Mansonela sp. 2, Onchocercidade gen. sp. 1, Onchocercidade gen. sp. 2, and Dirofilaria immitis. The morphological analysis supported the molecular findings. The domestic dogs were parasitized by Acanthocheilonema reconditum, representing a new locality record for this species. Phylogenetic analysis showed high genetic similarity among the four undetermined species and Mansonella spp., Brugia spp., and Wuchereria bancrofti. The presence of D. immitis in ring-tailed coatis may be result of spillover from dogs, even though the parasite was not diagnosed in the sampled dogs. The presence of several undetermined Onchocercidae species indicates the necessity of continuous investigations on wild and domestic animals from Neotropical area, especially considering the growing anthropic influence on forest remnants. Filarids are vector-borne Onchocercidae nematodes widely distributed around the world, related to several hosts, both wild and domestic, in different Biomes, including human-related species. In consequence to deforestation, environmental degradation, and climate changes, there has been an expansion in the distribution of vector-borne diseases around the world, such as those caused by filarids, in endemic tropical areas and even in temperate regions where they did not used to occur before. Thus, epidemiology and molecular genetic diversity studies of these filarial parasites are of great importance for three main reasons: zoonotic potential of many known species of filarids; the lack of data about the species inhabiting neotropical regions and the current worldwide deforestation and consequent habitat loss scenario, which favors the emergence or re-emergence of diseases resulting from the infection of domestic animals and humans by parasites that used to have as reservoirs only wild animals.
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Affiliation(s)
- Marcela Figuerêdo Duarte Moraes
- São Paulo State University–Unesp, Agrarian and Veterinarian Sciences School (FCAV), Department of Pathology, Reproduction, and One Health, Jaboticabal, Brazil
| | - Andressa de Souza Pollo
- São Paulo State University–Unesp, Agrarian and Veterinarian Sciences School (FCAV), Department of Pathology, Reproduction, and One Health, Jaboticabal, Brazil
| | - Estevam Guilherme Lux Hoppe
- São Paulo State University–Unesp, Agrarian and Veterinarian Sciences School (FCAV), Department of Pathology, Reproduction, and One Health, Jaboticabal, Brazil
- * E-mail:
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Ketz AC, Robinson SJ, Johnson CJ, Samuel MD. Pathogen‐mediated selection and management implications for white‐tailed deer exposed to chronic wasting disease. J Appl Ecol 2022. [DOI: 10.1111/1365-2664.14109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Alison C. Ketz
- Wisconsin Cooperative Research Unit Department of Forest and Wildlife Ecology University of Wisconsin Madison WI USA
| | - Stacie J. Robinson
- NOAA Hawaiian Monk Seal Research Program Pacific Islands Fisheries Science Center Honolulu HI USA
| | - Chad J. Johnson
- Medical Microbiology and Immunology University of Wisconsin Madison WI USA
| | - Michael D. Samuel
- Department of Forest and Wildlife Ecology University of Wisconsin Madison WI USA
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Catenacci LS, Oliveira JBS, De Vleeschouwer KM, de Carvalho Oliveira L, Deem SL, Sousa Júnior SCD, Santos KRD. Gastrointestinal parasites of Leontopithecus chrysomelas in the Atlantic Forest, Brazil. REVISTA BRASILEIRA DE PARASITOLOGIA VETERINARIA = BRAZILIAN JOURNAL OF VETERINARY PARASITOLOGY : ORGAO OFICIAL DO COLEGIO BRASILEIRO DE PARASITOLOGIA VETERINARIA 2022; 31:e013521. [PMID: 35195183 PMCID: PMC9901878 DOI: 10.1590/s1984-29612022005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 12/10/2021] [Indexed: 11/21/2022]
Abstract
We performed coproparasitological testing of free-living golden-headed lion tamarins, Leontopithecus chrysomelas, using the Hoffmann-Pons-Janner method. In total, we collected 118 samples from ten groups: four living in Federal Protected Area and six living in Non-Protected Areas of cocoa farms. Eggs from parasites of the Acanthocephala phylum and Spiruridae, Ancylostomatidae, Ascarididae and Oxyuridae families were identified, as well as the genus Strongyloides (Nematode: Strongyloididae) and phylum Apicomplexa. This is the first description of infection with coccidian, Trichuridae family and Strongyloides spp. in L. chrysomelas. A total of 48% (n= 57) of the animals were infected and the highest prevalence (37.2±SD 8.72, n = 44) was for Acanthocephalidae, followed by Spiruridae (8.5±SD 5.03, n = 10). There was no difference in parasite prevalence by age classes or sex. However, we found higher diversity and prevalence of parasites in animals living in the Federal Protected Area. These results suggest that intestinal parasites may be influenced by environmental factors, such as the management of the areas where the animals live, in addition to the feeding behavior of L. chrysomelas and distinct transmission strategies of parasites. The combination of ecological and demographic data combined with parasitological studies may contribute to conservation programs for this species.
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Affiliation(s)
- Lilian Silva Catenacci
- Programa de Pós-Graduação em Tecnologias em Animais de Interesse Regional - PPGTAIR, Universidade Federal do Piauí, Teresina, PI, Brasil.,Programa de Pós-Graduação em Saúde Animal na Amazônia - PPGSAAM, Universidade Federal do Pará, Castanhal, PA, Brasil.,Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium.,Saint Louis Zoo Institute for Conservation Medicine, Saint Louis, MO, United States
| | | | | | - Leonardo de Carvalho Oliveira
- Departamento de Ciência, Universidade Estadual do Rio de Janeiro, Rio de Janeiro, RJ, Brasil.,Bicho do Mato Instituto de Pesquisa, Belo Horizonte, MG, Brasil
| | - Sharon Lynn Deem
- Saint Louis Zoo Institute for Conservation Medicine, Saint Louis, MO, United States
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Gut Microbiota Implications for Health and Welfare in Farm Animals: A Review. Animals (Basel) 2021; 12:ani12010093. [PMID: 35011199 PMCID: PMC8749645 DOI: 10.3390/ani12010093] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 12/24/2021] [Accepted: 12/28/2021] [Indexed: 12/11/2022] Open
Abstract
Simple Summary Farm animal health and welfare have been paid increasing concern in the world, which is generally assessed by the measurements of physical health, immune response, behavior, and physiological indicators, such as stress-related hormone, cortisone, and norepinephrine. Gut microbiota as a “forgotten organ” has been reported for its great influence on the host phenotypes through the immune, neural, and endocrine pathways to affect the host health and behavior. In addition, fecal microbiota transplantation as a novel approach is applied to regulating the composition and function of the recipient farm animals. In this review, we summarized recent studies that gut microbiota influenced health, immunity, behavior, and stress response, as well as the progress of fecal microbiota transplantation in farm animals. The review will provide new insights into the measurement of farm animal health and welfare concerning gut microbiota, and the implication of fecal microbiota transplantation to improve productivity, health, and welfare. Above all, this review suggests that gut microbiota is a promising field to evaluate and improve animal welfare. Abstract In the past few decades, farm animal health and welfare have been paid increasing concern worldwide. Farm animal health and welfare are generally assessed by the measurements of physical health, immune response, behavior, and physiological indicators. The gut microbiota has been reported to have a great influence on host phenotypes, possibly via the immune processes, neural functions, and endocrine pathways, thereby influencing host phenotypes. However, there are few reviews regarding farm animals’ health and welfare status concerning the gut microbiota. In this point of view, (1) we reviewed recent studies showing that gut microbiota (higher alpha diversity, beneficial composition, and positive functions) effectively influenced health characteristics, immunity, behaviors, and stress response in farm animals (such as pigs, chickens, and cows), which would provide a novel approach to measure and evaluate the health status and welfare of farm animals. In addition, fecal microbiota transplantation (FMT) as one of the methods can modulate the recipient individual’s gut microbiota to realize the expected phenotype. Further, (2) we highlighted the application of FMT on the improvement of the production performance, the reduction in disease and abnormal behavior, as well as the attenuation of stress in farm animals. It is concluded that the gut microbiota can be scientifically used to assess and improve the welfare of farm animals. Moreover, FMT may be a helpful strategy to reduce abnormal behavior and improve stress adaption, as well as the treatment of disease for farm animals. This review suggests that gut microbiota is a promising field to evaluate and improve animal welfare.
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Torfs JRR, Eens M, Laméris DW, Staes N. Respiratory Disease Risk of Zoo-Housed Bonobos Is Associated with Sex and Betweenness Centrality in the Proximity Network. Animals (Basel) 2021; 11:3597. [PMID: 34944372 PMCID: PMC8698162 DOI: 10.3390/ani11123597] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/16/2021] [Accepted: 12/17/2021] [Indexed: 12/24/2022] Open
Abstract
Infectious diseases can be considered a threat to animal welfare and are commonly spread through both direct and indirect social interactions with conspecifics. This is especially true for species with complex social lives, like primates. While several studies have investigated the impact of sociality on disease risk in primates, only a handful have focused on respiratory disease, despite it being a major cause of morbidity and mortality in both wild and captive populations and thus an important threat to primate welfare. Therefore, we examined the role of social-network position on the occurrence of respiratory disease symptoms during one winter season in a relatively large group of 20 zoo-housed bonobos with managed fission-fusion dynamics. We found that within the proximity network, symptoms were more likely to occur in individuals with higher betweenness centrality, which are individuals that form bridges between different parts of the network. Symptoms were also more likely to occur in males than in females, independent of their social-network position. Taken together, these results highlight a combined role of close proximity and sex in increased risk of attracting respiratory disease, two factors that can be taken into account for further welfare management of the species.
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Affiliation(s)
- Jonas R. R. Torfs
- Behavioral Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium; (M.E.); (D.W.L.); (N.S.)
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium
| | - Marcel Eens
- Behavioral Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium; (M.E.); (D.W.L.); (N.S.)
| | - Daan W. Laméris
- Behavioral Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium; (M.E.); (D.W.L.); (N.S.)
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium
| | - Nicky Staes
- Behavioral Ecology and Ecophysiology Group, Department of Biology, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium; (M.E.); (D.W.L.); (N.S.)
- Centre for Research and Conservation, Royal Zoological Society of Antwerp, Koningin Astridplein 26, 2018 Antwerp, Belgium
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Podgórski T, Pepin KM, Radko A, Podbielska A, Łyjak M, Woźniakowski G, Borowik T. How do genetic relatedness and spatial proximity shape African swine fever infections in wild boar? Transbound Emerg Dis 2021; 69:2656-2666. [PMID: 34902218 DOI: 10.1111/tbed.14418] [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: 07/09/2021] [Revised: 10/31/2021] [Accepted: 11/30/2021] [Indexed: 11/29/2022]
Abstract
The importance of social and spatial structuring of wildlife populations for disease spread, though widely recognized, is still poorly understood in many host-pathogen systems. In particular, system specific kin relationships among hosts can create contact heterogeneities and differential disease transmission rates. Here, we investigate how distance-dependent infection risk is influenced by genetic relatedness in a novel host-pathogen system: wild boar (Sus scrofa) and African swine fever (ASF). We hypothesized that infection risk would correlate positively with proximity and relatedness to ASF-infected individuals but expected those relationships to weaken with distance between individuals due to decay in contact rates and genetic similarity. We genotyped 323 wild boar samples (243 ASF-negative and 80 ASF-positive) collected in north-eastern Poland in 2014-2016 and modeled the effects of geographic distance, genetic relatedness, and ASF virus transmission mode (direct or carcass-based) on the probability of ASF infection. Infection risk was positively associated with spatial proximity and genetic relatedness to infected individuals with generally stronger effect of distance. In the high-contact zone (0-2 km), infection risk was shaped by the presence of infected individuals rather than by relatedness to them. In the medium-contact zone (2-5 km), infection risk decreased but was still associated with relatedness and paired infections were more frequent among relatives. At farther distances, infection risk further declined with relatedness and proximity to positive individuals, and was 60% lower among unrelated individuals in the no-contact zone (33% in10-20 km) compared with among relatives in the high-contact zone (93% in 0-2 km). Transmission mode influenced the relationship between proximity or relatedness and infection risk. Our results indicate that the presence of nearby infected individuals is most important for shaping ASF infection rates through carcass-based transmission, while relatedness plays an important role in shaping transmission rates between live animals. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Tomasz Podgórski
- Mammal Research Institute, Polish Academy of Sciences, Stoczek 1, Białowieża, 17-230, Poland.,Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Kamýcká 129, Prague, 165 00, Czech Republic
| | - Kim M Pepin
- National Wildlife Research Center, USDA, APHIS, Wildlife Services, 4101 Laporte Ave., Fort Collins, CO, 80526
| | - Anna Radko
- Department of Animal Molecular Biology, National Research Institute of Animal Production, Krakowska 1, Balice, 32-083, Poland
| | - Angelika Podbielska
- Department of Animal Molecular Biology, National Research Institute of Animal Production, Krakowska 1, Balice, 32-083, Poland
| | - Magdalena Łyjak
- Department of Swine Diseases, National Veterinary Research Institute, Partyzantów 57, Pulawy, 24-100, Poland
| | - Grzegorz Woźniakowski
- Deparment of Diagnosis and Clinical Sciences, Faculty of Biological and Veterinary Sciences, Nicolaus Copernicus University, Lwowska 1, Torun, 87-100, Poland
| | - Tomasz Borowik
- Mammal Research Institute, Polish Academy of Sciences, Stoczek 1, Białowieża, 17-230, Poland
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Downie AE, Mayer A, Metcalf CJE, Graham AL. Optimal immune specificity at the intersection of host life history and parasite epidemiology. PLoS Comput Biol 2021; 17:e1009714. [PMID: 34932551 PMCID: PMC8730424 DOI: 10.1371/journal.pcbi.1009714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Revised: 01/05/2022] [Accepted: 12/02/2021] [Indexed: 11/30/2022] Open
Abstract
Hosts diverge widely in how, and how well, they defend themselves against infection and immunopathology. Why are hosts so heterogeneous? Both epidemiology and life history are commonly hypothesized to influence host immune strategy, but the relationship between immune strategy and each factor has commonly been investigated in isolation. Here, we show that interactions between life history and epidemiology are crucial for determining optimal immune specificity and sensitivity. We propose a demographically-structured population dynamics model, in which we explore sensitivity and specificity of immune responses when epidemiological risks vary with age. We find that variation in life history traits associated with both reproduction and longevity alters optimal immune strategies-but the magnitude and sometimes even direction of these effects depends on how epidemiological risks vary across life. An especially compelling example that explains previously-puzzling empirical observations is that depending on whether infection risk declines or rises at reproductive maturity, later reproductive maturity can select for either greater or lower immune specificity, potentially illustrating why studies of lifespan and immune variation across taxa have been inconclusive. Thus, the sign of selection on the life history-immune specificity relationship can be reversed in different epidemiological contexts. Drawing on published life history data from a variety of chordate taxa, we generate testable predictions for this facet of the optimal immune strategy. Our results shed light on the causes of the heterogeneity found in immune defenses both within and among species and the ultimate variability of the relationship between life history and immune specificity.
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Affiliation(s)
- Alexander E. Downie
- Department of Ecology & Evolutionary Biology, Princeton University, Princeton, New Jersey, United States of America
| | - Andreas Mayer
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, United States of America
| | - C. Jessica E. Metcalf
- Department of Ecology & Evolutionary Biology, Princeton University, Princeton, New Jersey, United States of America
- School of Public and International Affairs, Princeton University, Princeton, New Jersey, United States of America
| | - Andrea L. Graham
- Department of Ecology & Evolutionary Biology, Princeton University, Princeton, New Jersey, United States of America
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Chrétien E, Boisclair D, Cooke SJ, Killen SS. Social Group Size and Shelter Availability Influence Individual Metabolic Traits in a Social Fish. Integr Org Biol 2021; 3:obab032. [PMID: 34859193 PMCID: PMC8633746 DOI: 10.1093/iob/obab032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 09/22/2021] [Accepted: 10/28/2021] [Indexed: 11/14/2022] Open
Abstract
Group living is widespread among animal species and yields both costs and benefits. Presence of conspecifics can restrict or enhance the expression of individual behavior, and the recent social environment is thought to affect behavioral responses in later contexts, even when individuals are alone. However, little is known about how social group size influences the expression of individual physiological traits, including metabolic rates. There is some evidence that shoaling can reduce fish metabolic rates but this variable may be affected by habitat conditions such as shelter availability via density-dependent processes. We investigated how social group size and shelter availability influence Eurasian minnow (Phoxinus phoxinus) metabolic rates estimated by respirometry. Respirometry trials were conducted on fish in isolation before and after they were housed for 3 weeks in a social treatment consisting in a specific group size (n = 4 or 8) and shelter availability (presence or absence of plant shelter in the experimental tank). Plant shelter was placed over respirometers for half of the duration of the respirometry trials, allowing estimation of minimum daytime and nighttime metabolic rates in both conditions (in the presence or absence of plant shelter). Standard metabolic rate (SMR), maximum metabolic rate (MMR), and aerobic scope were also estimated over the entire trial. Minimum daytime and nighttime metabolic rates estimated while in presence of plant shelter were lower than when estimated in absence of plant shelter, both before and after individuals were housed in their social treatment. After the social treatment, SMRs were higher for fish that were held in groups of 4 as compared with those of fish held in groups of 8, while MMR showed no difference. Plant shelter availability during the social treatments did not influence SMR or MMR. Our results suggest that social group size may directly influence energy demands of individuals, highlighting the importance of understanding the role of group size on variations in physiological traits associated with energy expenditure.
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Affiliation(s)
- Emmanuelle Chrétien
- Département de sciences biologiques, Université de Montréal, Campus MIL, 1375 Av. Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, Canada
- Groupe interuniversitaire en limnologie et environnement aquatique (GRIL), Campus MIL, 1375 Av. Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, Canada
| | - Daniel Boisclair
- Département de sciences biologiques, Université de Montréal, Campus MIL, 1375 Av. Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, Canada
- Groupe interuniversitaire en limnologie et environnement aquatique (GRIL), Campus MIL, 1375 Av. Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, Canada
| | - Steven J Cooke
- Fish Ecology and Conservation Physiology Laboratory, Department of Biology and Institute of Environmental and Interdisciplinary Science, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6, Canada
| | - Shaun S Killen
- Groupe interuniversitaire en limnologie et environnement aquatique (GRIL), Campus MIL, 1375 Av. Thérèse-Lavoie-Roux, Montréal, QC H2V 0B3, Canada
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
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Schmid-Hempel P. Sociality and parasite transmission. Behav Ecol Sociobiol 2021; 75:156. [PMID: 34720348 PMCID: PMC8540878 DOI: 10.1007/s00265-021-03092-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 09/23/2021] [Accepted: 09/27/2021] [Indexed: 11/18/2022]
Abstract
Parasites and their social hosts form many different relationships. But what kind of selection regimes are important? A look at the parameters that determine fitness of the two parties suggests that social hosts differ from solitary ones primarily in the structure of transmission pathways. Because transmission is, both, the physical encounter of a new host and infecting it, several different elements determine parasite transmission success. These include spatial distance, genetic distance, or the temporal and ecological niche overlaps. Combing these elements into a ‘generalized transmission distance’ that determines parasite fitness aids in the identification of the critical steps. For example, short-distance transmission to genetically similar hosts within the social group is the most frequent process under sociality. Therefore, spatio-genetical distances are the main driver of parasite fitness. Vice versa, the generalized distance identifies the critical host defences. In this case, host defences should be primarily selected to defend against the within-group spread of an infection, especially among closely related group members.
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Affiliation(s)
- Paul Schmid-Hempel
- Institute of Integrative Biology (IBZ), ETH Zürich, ETH-Zentrum CHN, Universitätstrasse 16, CH-8092 Zürich, Switzerland
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Wielgus E, Caron A, Bennitt E, De Garine‐Wichatitsky M, Cain B, Fritz H, Miguel E, Cornélis D, Chamaillé‐Jammes S. Inter‐Group Social Behavior, Contact Patterns and Risk for Pathogen Transmission in Cape Buffalo Populations. J Wildl Manage 2021. [DOI: 10.1002/jwmg.22116] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Elodie Wielgus
- Department of Natural Sciences Manchester Metropolitan University, All Saints Manchester M15 6BH UK
| | - Alexandre Caron
- Faculdade de Veterinária Universidade Eduardo Mondlane Av. De Moçambique, CP 257 Maputo Mozambique
| | - Emily Bennitt
- Okavango Research Institute University of Botswana Shorobe Road Maun Botswana
| | | | - Bradley Cain
- Department of Natural Sciences Manchester Metropolitan University, All Saints Manchester M15 6BH UK
| | - Herve Fritz
- REHABS, CNRS ‐ Université Lyon 1 ‐ Nelson Mandela University International Research Laboratory George Campus, Madiba Drive George South Africa
| | - Eve Miguel
- Maladies Infectieuses et Vecteurs: Ecologie, Génétique, Evolution et Contrôle Institut de Recherche pour le Développement 911 Avenue Agropolis, 34394 Montpellier cedex 5 France
| | - Daniel Cornélis
- CIRAD, Forêts et Sociétés, F‐34398 Montpellier, France; Forêts et Sociétés Université de Montpellier CIRAD, 34090 Montpellier France
| | - Simon Chamaillé‐Jammes
- CEFE, University of Montpellier, CNRS, EPHE, IRD University Paul Valéry Montpellier 3 Montpellier France
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Duncan C, Manser MB, Clutton‐Brock T. Decline and fall: The causes of group failure in cooperatively breeding meerkats. Ecol Evol 2021; 11:14459-14474. [PMID: 34765119 PMCID: PMC8571573 DOI: 10.1002/ece3.7655] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/15/2021] [Accepted: 02/28/2021] [Indexed: 12/30/2022] Open
Abstract
In many social vertebrates, variation in group persistence exerts an important effect on individual fitness and population demography. However, few studies have been able to investigate the failure of groups or the causes of the variation in their longevity. We use data from a long-term study of cooperatively breeding meerkats, Suricata suricatta, to investigate the different causes of group failure and the factors that drive these processes. Many newly formed groups failed within a year of formation, and smaller groups were more likely to fail. Groups that bred successfully and increased their size could persist for several years, even decades. Long-lived groups principally failed in association with the development of clinical tuberculosis, Mycobacterium suricattae, a disease that can spread throughout the group and be fatal for group members. Clinical tuberculosis was more likely to occur in groups that had smaller group sizes and that had experienced immigration.
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Affiliation(s)
- Chris Duncan
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Kalahari Research Centre, Kuruman River ReserveVan ZylsrusSouth Africa
| | - Marta B. Manser
- Kalahari Research Centre, Kuruman River ReserveVan ZylsrusSouth Africa
- Animal BehaviourDepartment of Evolutionary Biology and Environmental StudiesUniversity of ZurichZurichSwitzerland
| | - Tim Clutton‐Brock
- Department of ZoologyUniversity of CambridgeCambridgeUK
- Kalahari Research Centre, Kuruman River ReserveVan ZylsrusSouth Africa
- Mammal Research InstituteUniversity of PretoriaPretoriaSouth Africa
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Solórzano-García B, Vázquez-Domínguez E, Pérez-Ponce de León G, Piñero D. Co-structure analysis and genetic associations reveal insights into pinworms (Trypanoxyuris) and primates (Alouatta palliata) microevolutionary dynamics. BMC Ecol Evol 2021; 21:190. [PMID: 34670486 PMCID: PMC8527708 DOI: 10.1186/s12862-021-01924-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 10/13/2021] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND In parasitism arm race processes and red queen dynamics between host and parasites reciprocally mold many aspects of their genetics and evolution. We performed a parallel assessment of population genetics and demography of two species of pinworms with different degrees of host specificity (Trypanoxyuris multilabiatus, species-specific; and T. minutus, genus-specific) and their host, the mantled howler monkey (Alouatta palliata), based on mitochondrial DNA sequences and microsatellite loci (these only for the host). Given that pinworms and primates have a close co-evolutionary history, covariation in several genetic aspects of their populations is expected. RESULTS Mitochondrial DNA revealed two genetic clusters (West and East) in both pinworm species and howler monkeys, although population structure and genetic differentiation were stronger in the host, while genetic diversity was higher in pinworms than howler populations. Co-divergence tests showed no congruence between host and parasite phylogenies; nonetheless, a significant correlation was found between both pinworms and A. palliata genetic pairwise distances suggesting that the parasites' gene flow is mediated by the host dispersal. Moreover, the parasite most infective and the host most susceptible haplotypes were also the most frequent, whereas the less divergent haplotypes tended to be either more infective (for pinworms) or more susceptible (for howlers). Finally, a positive correlation was found between pairwise p-distance of host haplotypes and that of their associated pinworm haplotypes. CONCLUSION The genetic configuration of pinworm populations appears to be molded by their own demography and life history traits in conjunction with the biology and evolutionary history of their hosts, including host genetic variation, social interactions, dispersal and biogeography. Similarity in patterns of genetic structure, differentiation and diversity is higher between howler monkeys and T. multilabiatus in comparison with T. minutus, highlighting the role of host-specificity in coevolving processes. Trypanoxyuris minutus exhibits genetic specificity towards the most frequent host haplotype as well as geographic specificity. Results suggest signals of potential local adaptation in pinworms and further support the notion of correlated evolution between pinworms and their primate hosts.
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Affiliation(s)
- Brenda Solórzano-García
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, 04510, Mexico City, Mexico
- Departamento de Sistemas y Procesos Naturales, Escuela Nacional de Estudios Superiores - Merida, Universidad Nacional Autónoma de México, Yucatán, Mexico
| | - Ella Vázquez-Domínguez
- Departamento de Ecología de la Biodiversidad, Instituto de Ecología, Universidad Nacional Autónoma de México, 04510, Mexico City, Mexico.
| | - Gerardo Pérez-Ponce de León
- Instituto de Biología, Universidad Nacional Autónoma de México, 04510, Mexico City, Mexico
- Departamento de Sistemas y Procesos Naturales, Escuela Nacional de Estudios Superiores - Merida, Universidad Nacional Autónoma de México, Yucatán, Mexico
| | - Daniel Piñero
- Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, 04510, Mexico City, Mexico
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Wang YXG, Matson KD, Santini L, Visconti P, Hilbers JP, Huijbregts MAJ, Xu Y, Prins HHT, Allen T, Huang ZYX, de Boer WF. Mammal assemblage composition predicts global patterns in emerging infectious disease risk. GLOBAL CHANGE BIOLOGY 2021; 27:4995-5007. [PMID: 34214237 PMCID: PMC8518613 DOI: 10.1111/gcb.15784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 06/13/2021] [Accepted: 06/13/2021] [Indexed: 06/13/2023]
Abstract
As a source of emerging infectious diseases, wildlife assemblages (and related spatial patterns) must be quantitatively assessed to help identify high-risk locations. Previous assessments have largely focussed on the distributions of individual species; however, transmission dynamics are expected to depend on assemblage composition. Moreover, disease-diversity relationships have mainly been studied in the context of species loss, but assemblage composition and disease risk (e.g. infection prevalence in wildlife assemblages) can change without extinction. Based on the predicted distributions and abundances of 4466 mammal species, we estimated global patterns of disease risk through the calculation of the community-level basic reproductive ratio R0, an index of invasion potential, persistence, and maximum prevalence of a pathogen in a wildlife assemblage. For density-dependent diseases, we found that, in addition to tropical areas which are commonly viewed as infectious disease hotspots, northern temperate latitudes included high-risk areas. We also forecasted the effects of climate change and habitat loss from 2015 to 2035. Over this period, many local assemblages showed no net loss of species richness, but the assemblage composition (i.e. the mix of species and their abundances) changed considerably. Simultaneously, most areas experienced a decreased risk of density-dependent diseases but an increased risk of frequency-dependent diseases. We further explored the factors driving these changes in disease risk. Our results suggest that biodiversity and changes therein jointly influence disease risk. Understanding these changes and their drivers and ultimately identifying emerging infectious disease hotspots can help health officials prioritize resource distribution.
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Affiliation(s)
- Yingying X. G. Wang
- Wildlife Ecology and Conservation GroupWageningen University and ResearchWageningenThe Netherlands
- Department of Biological and Environmental ScienceUniversity of JyväskyläJyväskyläFinland
| | - Kevin D. Matson
- Wildlife Ecology and Conservation GroupWageningen University and ResearchWageningenThe Netherlands
| | - Luca Santini
- Department of Biology and Biotechnologies “Charles Darwin”Sapienza University of RomeRomeItaly
- Institute of Research on Terrestrial Ecosystems (CNR‐IRET)National Research CouncilMonterotondo (Rome)Italy
- Department of Environmental ScienceRadboud UniversityNijmegenThe Netherlands
| | - Piero Visconti
- International Institute for Applied System AnalysisLaxenburgAustria
- Institute of ZoologyZoological Society of LondonLondonUK
| | - Jelle P. Hilbers
- Department of Environmental ScienceRadboud UniversityNijmegenThe Netherlands
| | | | - Yanjie Xu
- Wildlife Ecology and Conservation GroupWageningen University and ResearchWageningenThe Netherlands
- The Finnish Museum of Natural HistoryUniversity of HelsinkiHelsinkiFinland
| | - Herbert H. T. Prins
- Wildlife Ecology and Conservation GroupWageningen University and ResearchWageningenThe Netherlands
- Department of Animal SciencesWageningen University and ResearchWageningenThe Netherlands
| | | | - Zheng Y. X. Huang
- Wildlife Ecology and Conservation GroupWageningen University and ResearchWageningenThe Netherlands
- College of Life SciencesNanjing Normal UniversityNanjingChina
| | - Willem F. de Boer
- Wildlife Ecology and Conservation GroupWageningen University and ResearchWageningenThe Netherlands
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Attractiveness of female sexual signaling predicts differences in female grouping patterns between bonobos and chimpanzees. Commun Biol 2021; 4:1119. [PMID: 34556787 PMCID: PMC8460808 DOI: 10.1038/s42003-021-02641-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 09/06/2021] [Indexed: 12/27/2022] Open
Abstract
Here we show that sexual signaling affects patterns of female spatial association differently in chimpanzees and bonobos, indicating its relevance in shaping the respective social systems. Generally, spatial association between females often mirrors patterns and strength of social relationships and cooperation within groups. While testing for proposed differences in female-female associations underlying female coalition formation in the species of the genus Pan, we find only limited evidence for a higher female-female gregariousness in bonobos. While bonobo females exhibited a slightly higher average number of females in their parties, there is neither a species difference in the time females spent alone, nor in the number of female party members in the absence of sexually attractive females. We find that the more frequent presence of maximally tumescent females in bonobos is associated with a significantly stronger increase in the number of female party members, independent of variation in a behavioural proxy for food abundance. This indicates the need to look beyond ecology when explaining species differences in female sociality as it refutes the idea that the higher gregariousness among bonobo females is driven by ecological factors alone and highlights that the temporal distribution of female sexual receptivity is an important factor to consider when studying mammalian sociality. Surbeck and colleagues investigate the proximate drivers of female gregariousness in bonobos and chimpanzees across different observed communities. Their findings indicate that varied levels of sexual signalling in these two species result in different social behaviours regarding female grouping and potentially cooperation.
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The ecology of zoonotic parasites in the Carnivora. Trends Parasitol 2021; 37:1096-1110. [PMID: 34544647 DOI: 10.1016/j.pt.2021.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 08/24/2021] [Accepted: 08/25/2021] [Indexed: 01/08/2023]
Abstract
The order Carnivora includes over 300 species that vary many orders of magnitude in size and inhabit all major biomes, from tropical rainforests to polar seas. The high diversity of carnivore parasites represents a source of potential emerging diseases of humans. Zoonotic risk from this group may be driven in part by exceptionally high functional diversity of host species in behavioral, physiological, and ecological traits. We review global macroecological patterns of zoonotic parasites within carnivores, and explore the traits of species that serve as hosts of zoonotic parasites. We synthesize theoretical and empirical research and suggest future work on the roles of carnivores as biotic multipliers, regulators, and sentinels of zoonotic disease as timely research frontiers.
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Social group size influences pathogen transmission in salamanders. Behav Ecol Sociobiol 2021. [DOI: 10.1007/s00265-021-03057-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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A metapopulation model of social group dynamics and disease applied to Yellowstone wolves. Proc Natl Acad Sci U S A 2021; 118:2020023118. [PMID: 33649227 DOI: 10.1073/pnas.2020023118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The population structure of social species has important consequences for both their demography and transmission of their pathogens. We develop a metapopulation model that tracks two key components of a species' social system: average group size and number of groups within a population. While the model is general, we parameterize it to mimic the dynamics of the Yellowstone wolf population and two associated pathogens: sarcoptic mange and canine distemper. In the initial absence of disease, we show that group size is mainly determined by the birth and death rates and the rates at which groups fission to form new groups. The total number of groups is determined by rates of fission and fusion, as well as environmental resources and rates of intergroup aggression. Incorporating pathogens into the models reduces the size of the host population, predominantly by reducing the number of social groups. Average group size responds in more subtle ways: infected groups decrease in size, but uninfected groups may increase when disease reduces the number of groups and thereby reduces intraspecific aggression. Our modeling approach allows for easy calculation of prevalence at multiple scales (within group, across groups, and population level), illustrating that aggregate population-level prevalence can be misleading for group-living species. The model structure is general, can be applied to other social species, and allows for a dynamic assessment of how pathogens can affect social structure and vice versa.
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