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Hediger JA, Spencer BD, Rice MF, Hopper ML, DeYoung RW, Ortega-Santos JA, Fulbright TE, Hewitt DG, Foley AM, Schofield LR, Campbell TA, Sheriff MJ, Cherry MJ. Physiological carry-over effects of variable precipitation are mediated by reproductive status in a long-lived ungulate. CONSERVATION PHYSIOLOGY 2024; 12:coae045. [PMID: 38974502 PMCID: PMC11224986 DOI: 10.1093/conphys/coae045] [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: 08/01/2023] [Revised: 06/04/2024] [Accepted: 06/14/2024] [Indexed: 07/09/2024]
Abstract
In the age of global climate change, extreme climatic events are expected to increase in frequency and severity. Animals will be forced to cope with these novel stressors in their environment. Glucocorticoids (i.e. 'stress' hormones) facilitate an animal's ability to cope with their environment. To date, most studies involving glucocorticoids focus on the immediate physiological effects of an environmental stressor on an individual, few studies have investigated the long-term physiological impacts of such stressors. Here, we tested the hypothesis that previous exposure to an environmental stressor will impart lasting consequences to an individual's glucocorticoid levels. In semi-arid environments, variable rainfall drives forage availability for herbivores. Reduced seasonal precipitation can present an extreme environmental stressor potentially imparting long-term impacts on an individual's glucocorticoid levels. We examined the effects of rainfall and environmental characteristics (i.e. soil and vegetation attributes) during fawn-rearing (i.e. summer) on subsequent glucocorticoid levels of female white-tailed deer (Odocoileus virginianus) in autumn. We captured 124 adult (≥2.5-year-old) female deer via aerial net-gunning during autumn of 2015, 2016 and 2021 across four populations spanning a gradient of environmental characteristics and rainfall in the semi-arid environment of South Texas, USA. We found for every 1 cm decrease in summer rainfall, faecal glucocorticoid levels in autumn increased 6.9%, but only in lactating females. Glucocorticoid levels in non-lactating, female deer were relatively insensitive to environmental conditions. Our study demonstrates the long-lasting effects of environmental stressors on an individual's glucocorticoid levels. A better understanding of the long-term effects stressors impart on an individual's glucocorticoid levels will help to evaluate the totality of the cost of a stressor to an individual's welfare and predict the consequences of future climate scenarios.
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Affiliation(s)
- Joseph A Hediger
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
| | - Bryan D Spencer
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
| | - Michaela F Rice
- Minnesota Department of Natural Resources, 500 Lafayette Road North, Saint Paul, MN 55155, USA
| | - Miranda L Hopper
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
| | - Randy W DeYoung
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
| | - J Alfonso Ortega-Santos
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
| | - Timothy E Fulbright
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
| | - David G Hewitt
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
| | - Aaron M Foley
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
| | - Landon R Schofield
- East Foundation, 200 Concord Plaza Drive, Suite 410, San Antonio, TX 78216, USA
| | - Tyler A Campbell
- East Foundation, 200 Concord Plaza Drive, Suite 410, San Antonio, TX 78216, USA
| | - Michael J Sheriff
- Biology Department, University of Massachusetts-Dartmouth, 285 Old Westport Road, Dartmouth, MA 02747, USA
| | - Michael J Cherry
- Caesar Kleberg Wildlife Research Institute, Texas A&M University –Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA
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2
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Seeley KE, Proudfoot KL, Edes AN. The application of allostasis and allostatic load in animal species: A scoping review. PLoS One 2022; 17:e0273838. [PMID: 36040981 PMCID: PMC9426905 DOI: 10.1371/journal.pone.0273838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/16/2022] [Indexed: 11/25/2022] Open
Abstract
Principles of allostasis and allostatic load have been widely applied in human research to assess the impacts of chronic stress on physiological dysregulation. Over the last few decades, researchers have also applied these concepts to non-human animals. However, there is a lack of uniformity in how the concept of allostasis is described and assessed in animals. The objectives of this review were to: 1) describe the extent to which the concepts of allostasis and allostatic load are applied theoretically to animals, with a focus on which taxa and species are represented; 2) identify when direct assessments of allostasis or allostatic load are made, which species and contexts are represented, what biomarkers are used, and if an allostatic load index was constructed; and 3) detect gaps in the literature and identify areas for future research. A search was conducted using CABI, PubMed, Agricola, and BIOSIS databases, in addition to a complementary hand-search of 14 peer-reviewed journals. Search results were screened, and articles that included non-human animals, as well as the terms “allostasis” or “allostatic” in the full text, were included. A total of 572 articles met the inclusion criteria (108 reviews and 464 peer-reviewed original research). Species were represented across all taxa. A subset of 63 publications made direct assessments of allostatic load. Glucocorticoids were the most commonly used biomarker, and were the only biomarker measured in 25 publications. Only six of 63 publications (9.5%) constructed an allostatic load index, which is the preferred methodology in human research. Although concepts of allostasis and allostatic load are being applied broadly across animal species, most publications use single biomarkers that are more likely indicative of short-term rather than chronic stress. Researchers are encouraged to adopt methodologies used in human research, including the construction of species-specific allostatic load indexes.
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Affiliation(s)
- Kathryn E. Seeley
- Department of Preventive Medicine, The Ohio State University College of Veterinary Medicine, Columbus, Ohio, United States of America
- * E-mail:
| | - Kathryn L. Proudfoot
- Health Management, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, Prince Edward Island, Canada
| | - Ashley N. Edes
- Department of Reproductive and Behavioral Sciences, Saint Louis Zoo, St. Louis, Missouri, United States of America
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3
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Sandfoss MR, Brischoux F, Lillywhite HB. Intraspecific investigation of dehydration-enhanced innate immune performance and endocrine stress response to sublethal dehydration in a semi-aquatic species of pit viper. J Exp Biol 2022; 225:276533. [PMID: 35946379 DOI: 10.1242/jeb.243894] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 08/03/2022] [Indexed: 11/20/2022]
Abstract
Sublethal dehydration can cause negative physiological effects, but recent studies investigating the sub-lethal effects of dehydration on innate immune performance in reptiles have found a positive correlation between innate immune response and plasma osmolality. To investigate if this is an adaptive trait that evolved in response to dehydration in populations inhabiting water-scarce environments, we sampled free-ranging cottonmouths (n=26 adult cottonmouths) from two populations inhabiting contrasting environments in terms of water availability: Snake Key (n=12), an island with no permanent sources of fresh water and Paynes Prairie (n=14), a flooded freshwater prairie. In addition to field surveys, we manipulated the hydration state of 17 cottonmouths (Paynes Prairie n=9, Snake Key n=8) in a laboratory setting and measured the response of corticosterone and innate immune performance to dehydration with the aim of identifying any correlation or trade-offs between them. We measured corticosterone of cottonmouths at a baseline level and then again following a 60-min stress test when at three hydration states: hydrated, dehydrated, and rehydrated. We found that innate immune performance improved with dehydration and then returned to baseline levels within 48 hours of rehydration, which agrees with previous research in reptiles. Despite the frequent exposure of cottonmouths on Snake Key to dehydrating conditions, we did not find cottonmouths inhabiting the island to show a greater magnitude or more prolonged immune response compared to cottonmouths from Paynes Prairie. We also found a positive association between dehydration and corticosterone values.
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Affiliation(s)
- Mark R Sandfoss
- Department of Biology, University of Florida, Gainesville, Florida, USA
| | - François Brischoux
- Centre d'Etudes Biologiques de Chizé (CEBC), UMR 7372 CNRS and La Rochelle Université, 79360 Villiers en Bois, France
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4
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Stead SM, Bădescu I, Boonstra R. Of mammals and milk: how maternal stress affects nursing offspring. Mamm Rev 2021. [DOI: 10.1111/mam.12267] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Samantha M. Stead
- Department of Anthropology University of Toronto Scarborough 1265 Military Trail Scarborough ONM1C 1A4Canada
| | - Iulia Bădescu
- Département d’Anthropologie Université de Montréal 3150 Rue Jean‐Brillant Montréal QCH3T 1N8Canada
| | - Rudy Boonstra
- Department of Biological Sciences University of Toronto Scarborough 1265 Military Trail Scarborough ONM1C 1A4Canada
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5
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Skippington J, Manne T, Veth P. Isotopic Indications of Late Pleistocene and Holocene Paleoenvironmental Changes at Boodie Cave Archaeological Site, Barrow Island, Western Australia. Molecules 2021; 26:2582. [PMID: 33925244 PMCID: PMC8124622 DOI: 10.3390/molecules26092582] [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: 03/21/2021] [Revised: 04/25/2021] [Accepted: 04/26/2021] [Indexed: 11/17/2022] Open
Abstract
This paper presents the first application of mammal tooth enamel carbonate stable isotope analysis for the purpose of investigating late Pleistocene-early Holocene environmental change in an Australian archaeological context. Stable carbon (δ13C) and oxygen (δ18O) isotope ratios were analyzed from archaeological and modern spectacled hare wallaby (Lagorchestes conspicillatus) and hill kangaroo (Osphranter robustus) tooth enamel carbonates from Boodie Cave on Barrow Island in Western Australia. δ18O results track the dynamic paleoecological history at Boodie Cave including a clear shift towards increasing aridity preceding the onset of the Last Glacial Maximum and a period of increased humidity in the early to mid-Holocene. Enamel δ13C reflects divergent species feeding ecology and may imply a long-term shift toward increasing diversity in vegetation structure. This study contributes new data to the carbonate-isotope record for Australian fauna and demonstrates the significant potential of stable isotope based ecological investigations for tracking paleoenvironment change to inter-strata resolution.
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Affiliation(s)
- Jane Skippington
- Archaeology, School of Social Science, University of Western Australia, Perth, WA 6009, Australia;
| | - Tiina Manne
- School of Social Science, University of Queensland, Brisbane, QLD 4072, Australia;
| | - Peter Veth
- Archaeology, School of Social Science, University of Western Australia, Perth, WA 6009, Australia;
- Australian Centre for Excellence in Biodiversity and Heritage, University of Wollongong, Wollongong, NSW 2522, Australia
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Martínez-Pérez PA, Hyndman TH, Fleming PA. Haematology and blood chemistry in free-ranging quokkas (Setonix brachyurus): Reference intervals and assessing the effects of site, sampling time, and infectious agents. PLoS One 2020; 15:e0239060. [PMID: 32941511 PMCID: PMC7498088 DOI: 10.1371/journal.pone.0239060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 08/28/2020] [Indexed: 11/18/2022] Open
Abstract
Quokkas (Setonix brachyurus) are small macropodid marsupials from Western Australia, which are identified as of conservation concern. Studies on their blood analytes exist but involve small sample sizes and are associated with very little information concerning the health of the animals. Blood was collected from free-ranging quokkas from Rottnest Island (n = 113) and mainland (n = 37) Western Australia, between September 2010 and December 2011, to establish haematology and blood chemistry reference intervals. Differences in haematology and blood chemistry between sites (Rottnest Island v mainland) were significant for haematology (HMT, p = 0.003), blood chemistry (BLC, p = 0.001) and peripheral blood cell morphology (PBCM, p = 0.001). Except for alkaline phosphatase, all blood chemistry analytes were higher in mainland animals. There were also differences with time of year in HMT (p = 0.001), BLC (p = 0.001) and PBCM (p = 0.001) for Rottnest Island quokkas. A small sample of captive animals (n = 8) were opportunistically sampled for plasma concentrations of vitamin E and were found to be deficient compared with wild-caught animals. Fifty-eight of the 150 quokkas were also tested for the presence of Salmonella, microfilariae, Macropodid herpesvirus-6, Theileria spp., Babesia spp., trypanosomes, Cryptococcus spp. and other saprophytic fungi. All eight infectious agents were detected in this study. Infectious agents were detected in 24 of these 58 quokkas (41%), with more than one infectious agent detected for all 24 individuals. Salmonella were detected concurrently with microfilariae in 8 of these 24 quokkas, and this mixed infection was associated with lower values across all haematological analytes, with Salmonella having the greater involvement in the decreased haematological values (p < 0.05). There was no evidence for an effect of sex on HMT, BLC and PBCM. Our data provide important haematological and blood chemistry reference intervals for free-ranging quokkas. We applied novel methods of analyses to HMT and BLC that can be used more broadly, aiding identification of potential disease in wildlife.
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Affiliation(s)
| | - Timothy H. Hyndman
- School of Veterinary Medicine, Murdoch University, Murdoch, Western Australia, Australia
- * E-mail:
| | - Patricia A. Fleming
- Harry Butler Institute, Murdoch University, Murdoch, Western Australia, Australia
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7
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Fardell LL, Pavey CR, Dickman CR. Fear and stressing in predator-prey ecology: considering the twin stressors of predators and people on mammals. PeerJ 2020; 8:e9104. [PMID: 32391213 PMCID: PMC7196326 DOI: 10.7717/peerj.9104] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2019] [Accepted: 04/09/2020] [Indexed: 12/28/2022] Open
Abstract
Predators induce stress in prey and can have beneficial effects in ecosystems, but can also have negative effects on biodiversity if they are overabundant or have been introduced. The growth of human populations is, at the same time, causing degradation of natural habitats and increasing interaction rates of humans with wildlife, such that conservation management routinely considers the effects of human disturbance as tantamount to or surpassing those of predators. The need to simultaneously manage both of these threats is particularly acute in urban areas that are, increasingly, being recognized as global hotspots of wildlife activity. Pressures from altered predator-prey interactions and human activity may each initiate fear responses in prey species above those that are triggered by natural stressors in ecosystems. If fear responses are experienced by prey at elevated levels, on top of responses to multiple environmental stressors, chronic stress impacts may occur. Despite common knowledge of the negative effects of stress, however, it is rare that stress management is considered in conservation, except in intensive ex situ situations such as in captive breeding facilities or zoos. We propose that mitigation of stress impacts on wildlife is crucial for preserving biodiversity, especially as the value of habitats within urban areas increases. As such, we highlight the need for future studies to consider fear and stress in predator-prey ecology to preserve both biodiversity and ecosystem functioning, especially in areas where human disturbance occurs. We suggest, in particular, that non-invasive in situ investigations of endocrinology and ethology be partnered in conservation planning with surveys of habitat resources to incorporate and reduce the effects of fear and stress on wildlife.
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Affiliation(s)
- Loren L. Fardell
- School of Life and Environmental Sciences, University of Sydney, Sydney, NSW, Australia
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8
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Brunton EA, Clemente CJ, Burnett SE. Not all urban landscapes are the same: interactions between urban land use and stress in a large herbivorous mammal. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2020; 30:e02055. [PMID: 31828865 DOI: 10.1002/eap.2055] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 08/22/2019] [Accepted: 11/04/2019] [Indexed: 06/10/2023]
Abstract
Urbanization significantly impacts the health and viability of wildlife populations yet it is not well understood how urban landscapes differ from non-urban landscapes with regard to their effects on wildlife. This study investigated the physiological response of eastern grey kangaroos (Macropus giganteus) to land use at a landscape scale. Using fecal glucocorticoid metabolites (FGM) we compared stress levels of kangaroo populations in urban and non-urban environments. We modeled FGM concentrations from 24 kangaroo populations against land use (urban or non-urban) and other anthropogenic and environmental factors, using a linear modeling approach. We found that land use was a significant predictor of FGM concentrations in eastern grey kangaroos with significant differences in concentrations between urban and non-urban populations. However, the direction of the relationship differed between northern and southern regions of Australia. In the northern study sites, kangaroos in urban areas had significantly higher FGM levels than their non-urban counterparts. In contrast, in southern sites, where kangaroos occur in high densities in many urban areas, urban kangaroos had lower FGM concentrations than non-urban kangaroos. Rainfall and temperature were also significant predictors of FGM and the direction of the relationship was consistent across both regions. These results are consistent with the contrasting abundance and persistence of kangaroo populations within the urban matrix between the two study regions. In the northern region many populations have declined over the last two decades and are fragmented, also occurring at lower densities than in southern sites. Our study indicates that it is the characteristics of urban environments, rather than the urban environment per se, which determines the extent of impacts of urbanization on kangaroos. This research provides insights into how the design of urban landscapes can influence large mammal populations.
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Affiliation(s)
- Elizabeth A Brunton
- School of Science and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, Queensland, 4556, Australia
| | - Christofer J Clemente
- School of Science and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, Queensland, 4556, Australia
| | - Scott E Burnett
- School of Science and Engineering, University of the Sunshine Coast, 90 Sippy Downs Drive, Sippy Downs, Queensland, 4556, Australia
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9
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Letendre C, Sawyer E, Young LJ, Old JM. Immunosenescence in a captive semelparous marsupial, the red-tailed phascogale (Phascogale calura). BMC ZOOL 2018. [DOI: 10.1186/s40850-018-0036-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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10
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Dunlop J, Morris K. Environmental determination of body size in mammals: Rethinking ‘island dwarfism’ in the golden bandicoot. AUSTRAL ECOL 2018. [DOI: 10.1111/aec.12624] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Judy Dunlop
- Biodiversity and Conservation Science; Department of Biodiversity, Conservation and Attractions; Locked Bag 104, Bentley Delivery Centre Perth Western Australia Australia
| | - Keith Morris
- Biodiversity and Conservation Science; Department of Biodiversity, Conservation and Attractions; Locked Bag 104, Bentley Delivery Centre Perth Western Australia Australia
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11
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Bradshaw SD. A state of non-specific tension in living matter? Stress in Australian animals. Gen Comp Endocrinol 2017; 244:118-129. [PMID: 26449159 DOI: 10.1016/j.ygcen.2015.10.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Revised: 09/27/2015] [Accepted: 10/03/2015] [Indexed: 10/22/2022]
Abstract
Evidence of stress responses in Australian animals is reviewed through a series of case studies involving desert frogs and lizards, small carnivorous marsupials, desert wallabies, a dwarf kangaroo species, the quokka wallaby and a small nectarivorous bird. An operational definition of stress as "the physiological resultant of demands that exceed an animal's homeostatic capacities" is used to identify instances of stress responses in the field, and to gauge their intensity. Clear evidence of stress responses is found in small dasyurid marsupial carnivores, and desert agamid lizards, both of which are semelparous. Other instances of seasonal stress responses include the Rottnest Island quokka, the Barrow Island euro kangaroo and a small nectarivorous bird, the Silvereye. The review also highlights the high level of physiological adaptation of some desert wallabies, such as the Spectacled hare wallaby, which is able to maintain physiological homeostasis in the field when challenged by conditions of extreme drought. The importance of thermal and hygric refugia for the long-term survival or rock wallabies, which apparently lack any hormonal control of renal function, is also highlighted.
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Affiliation(s)
- S Don Bradshaw
- School of Animal Biology, The University of Western Australia, Perth, WA 6009, Australia.
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12
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Cooper CE. Endocrinology of osmoregulation and thermoregulation of Australian desert tetrapods: A historical perspective. Gen Comp Endocrinol 2017; 244:186-200. [PMID: 26449158 DOI: 10.1016/j.ygcen.2015.10.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 09/30/2015] [Accepted: 10/03/2015] [Indexed: 10/22/2022]
Abstract
Many Australian tetrapods inhabit desert environments characterised by low productivity, unpredictable rainfall, high temperatures and high incident solar radiation. Maintaining a homeostatic milieu intérieur by osmoregulation and thermoregulation are two physiological challenges faced by tetrapods in deserts, and the endocrine system plays an important role in regulating these processes. There is a considerable body of work examining the osmoregulatory role of antidiuretic hormones for Australian amphibians, reptiles and mammals, with particular contributions concerning their role and function for wild, free-living animals in arid environments. The osmoregulatory role of the natriuretic peptide system has received some attention, while the role of adrenal corticosteroids has been more thoroughly investigated for reptiles and marsupials. The endocrinology of thermoregulation has not received similar attention. Reptiles are best-studied, with research examining the influence of arginine vasotocin and melatonin on body temperature, the role of prostaglandins in heart rate hysteresis and the effect of melanocyte-stimulating hormone on skin reflectivity. Australian mammals have been under-utilised in studies examining the regulation, development and evolution of endothermy, and there is little information concerning the endocrinology of thermoregulation for desert species. There is a paucity of data concerning the endocrinology of osmoregulation and thermoregulation for Australian desert birds. Studies of Australian desert fauna have made substantial contributions to endocrinology, but there is considerable scope for further research. A co-ordinated approach to examine arid-habitat adaptations of the endocrine system in an environmental and evolutionary context would be of particular value.
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Affiliation(s)
- Christine Elizabeth Cooper
- Department of Environment and Agriculture, Curtin University, Perth, Western Australia 6847, Australia; School of Animal Biology, University of Western Australia, Crawley, Western Australia 6009, Australia.
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Sotohira Y, Suzuki K, Sano T, Arai C, Asakawa M, Hayashi H. Stress assessment using hair cortisol of kangaroos affected by the lumpy jaw disease. J Vet Med Sci 2017; 79:852-854. [PMID: 28302942 PMCID: PMC5447972 DOI: 10.1292/jvms.16-0633] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The aim of this study was to objectively assess stress of kangaroos affected by lumpy jaw disease (LJD) using plasma and hair cortisol concentrations. The plasma and hair samples were collected from kangaroos with LJD and healthy controls. Collected hair samples were extracted with methanol after washing with isopropanol, following which they were processed with the cortisol enzyme immunoassay kit. The plasma cortisol concentration of LJD animals tended to be higher than that of the control. Ventral hair cortisol, but not dorsal hair, of LJD animals was significantly higher than that of the control. In conclusion, stress in kangaroos infected with LJD could be assessed by measuring ventral hair cortisol.
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Affiliation(s)
- Yukari Sotohira
- School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan.,Itozu no mori Zoological Park, 4-1-8 Kamiitozu, Kokurakita, Kitakyushu, Fukuoka 803-0845, Japan
| | - Kazuyuki Suzuki
- School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan
| | - Tadashi Sano
- School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan
| | - Chigusa Arai
- School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan
| | - Mitsuhiko Asakawa
- School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan
| | - Hideaki Hayashi
- School of Veterinary Medicine, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501, Japan
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14
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Moeller KT, Demare G, Davies S, DeNardo DF. Dehydration enhances multiple physiological defense mechanisms in a desert lizard, Heloderma suspectum. J Exp Biol 2017; 220:2166-2174. [DOI: 10.1242/jeb.150367] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 03/27/2017] [Indexed: 11/20/2022]
Abstract
The physiological challenges associated with dehydration can induce an increase in plasma glucocorticoid concentrations, a response thought to provide the mechanism for dehydration suppressing immune function. However, a comprehensive examination of the interrelationship of dehydration, stress, and immune function has not been conducted within a single species. We previously demonstrated that Gila monsters (Heloderma suspectum), which inhabit a xeric environment with a predictable seasonal drought, have enhanced measures of innate immunity when dehydrated. These results suggest that, in this species, dehydration may not induce a glucocorticoid response, but, instead, enhances physiological defense mechanisms. To explore this possibility, we examined multiple measures of innate immunity as well as initial and reactive plasma concentrations of glucocorticoids in captive and free-ranging Gila monsters at various hydration states. Our results show that, in this species, dehydration alone does not cause a substantial increase in plasma glucocorticoids, and we provide broader evidence that dehydration enhances defensive mechanisms including stress reactivity and various measures of innate immune function. These findings suggest that physiological responses to dehydration may depend heavily on an organism's ecology. More research on the effects of dehydration on the glucocorticoid response and immunity will help clarify the interactive roles they play in response to hydric challenges and whether adaptations to water-limited environments influence these interactions.
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Affiliation(s)
- Karla T. Moeller
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Guillaume Demare
- School of Geography & the Environment, University of Oxford, Oxford, United Kingdom
| | - Scott Davies
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
| | - Dale F. DeNardo
- School of Life Sciences, Arizona State University, Tempe, AZ, USA
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Johnstone CP, Lill A, Reina RD. Use of erythrocyte indicators of health and condition in vertebrate ecophysiology: a review and appraisal. Biol Rev Camb Philos Soc 2015; 92:150-168. [PMID: 28075072 DOI: 10.1111/brv.12219] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 08/26/2015] [Accepted: 08/28/2015] [Indexed: 12/01/2022]
Abstract
We review evidence for and against the use of erythrocyte indicators of health status and condition, parasite infection level and physiological stress in free-living vertebrates. The use of indicators that are measured directly from the blood, such as haemoglobin concentration, haematocrit and erythrocyte sedimentation rate, and parameters that are calculated from multiple measured metrics, such as mean cell volume, mean cell haemoglobin content or mean cell haemoglobin concentration is evaluated. The evidence for or against the use of any given metric is equivocal when the relevant research is considered in total, although there is sometimes strong support for using a particular metric in a particular taxon. Possibly the usefulness of these metrics is taxon, environment or condition specific. Alternatively, in an uncontrolled environment where multiple factors are influencing a metric, its response to environmental change will sometimes, but not always, be predictable. We suggest that (i) researchers should validate a metric's utility before use, (ii) multiple metrics should be used to construct an overall erythrocyte profile for an individual or population, (iii) there is a need for researchers to compile reference ranges for free-living species, and (iv) some metrics which are useful under controlled, clinical conditions may not have the same utility or applicability for free-living vertebrates. Erythrocyte metrics provide useful information about health and condition that can be meaningfully interpreted in free-living vertebrates, but their use requires careful forethought about confounding factors.
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Affiliation(s)
- Christopher P Johnstone
- School of Biological Sciences, Monash University, Clayton Campus, Clayton, Victoria, 3800, Australia
| | - Alan Lill
- Department of Ecology, Environment and Evolution, School of Life Sciences, La Trobe University, Bundoora Campus, Bundoora, Victoria, 3068, Australia
| | - Richard D Reina
- School of Biological Sciences, Monash University, Clayton Campus, Clayton, Victoria, 3800, Australia
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Hing S, Narayan E, Thompson RCA, Godfrey S. A review of factors influencing the stress response in Australian marsupials. CONSERVATION PHYSIOLOGY 2014; 2:cou027. [PMID: 27293648 PMCID: PMC4732483 DOI: 10.1093/conphys/cou027] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Revised: 05/16/2014] [Accepted: 06/02/2014] [Indexed: 05/29/2023]
Abstract
Many Australian marsupials are threatened species. In order to manage in situ and ex situ populations effectively, it is important to understand how marsupials respond to threats. Stress physiology (the study of the response of animals to challenging stimuli), a key approach in conservation physiology, can be used to characterize the physiological response of wildlife to threats. We reviewed the literature on the measurement of glucocorticoids (GCs), endocrine indicators of stress, in order to understand the stress response to conservation-relevant stressors in Australian marsupials and identified 29 studies. These studies employed a range of methods to measure GCs, with faecal glucocorticoid metabolite enzyme immunoassay being the most common method. The main stressors considered in studies of marsupials were capture and handling. To date, the benefits of stress physiology have yet to be harnessed fully in marsupial conservation. Despite a theoretical base dating back to the 1960s, GCs have only been used to understand how 21 of the 142 extant species of Australian marsupial respond to stressors. These studies include merely six of the 60 marsupial species of conservation concern (IUCN Near Threatened to Critically Endangered). Furthermore, the fitness consequences of stress for Australian marsupials are rarely examined. Individual and species differences in the physiological stress response also require further investigation, because significant species-specific variations in GC levels in response to stressors can shed light on why some individuals or species are more vulnerable to stress factors while others appear more resilient. This review summarizes trends, knowledge gaps and future research directions for stress physiology research in Australian marsupial conservation.
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Affiliation(s)
- Stephanie Hing
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - Edward Narayan
- Environmental Futures Research Institute, Griffith School of Environment, Griffith University, Southport, QLD 4222, Australia
| | - R. C. Andrew Thompson
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
| | - Stephanie Godfrey
- School of Veterinary and Life Sciences, Murdoch University, Murdoch, WA 6150, Australia
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O’Shea TJ, Bowen RA, Stanley TR, Shankar V, Rupprecht CE. Variability in seroprevalence of rabies virus neutralizing antibodies and associated factors in a Colorado population of big brown bats (Eptesicus fuscus). PLoS One 2014; 9:e86261. [PMID: 24465996 PMCID: PMC3899234 DOI: 10.1371/journal.pone.0086261] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 12/11/2013] [Indexed: 12/25/2022] Open
Abstract
In 2001–2005 we sampled permanently marked big brown bats (Eptesicus fuscus) at summer roosts in buildings at Fort Collins, Colorado, for rabies virus neutralizing antibodies (RVNA). Seroprevalence was higher in adult females (17.9%, n = 2,332) than males (9.4%, n = 128; P = 0.007) or volant juveniles (10.2%, n = 738; P<0.0001). Seroprevalence was lowest in a drought year with local insecticide use and highest in the year with normal conditions, suggesting that environmental stress may suppress RVNA production in big brown bats. Seroprevalence also increased with age of bat, and varied from 6.2 to 26.7% among adult females at five roosts sampled each year for five years. Seroprevalence of adult females at 17 other roosts sampled for 1 to 4 years ranged from 0.0 to 47.1%. Using logistic regression, the only ranking model in our candidate set of explanatory variables for serological status at first sampling included year, day of season, and a year by day of season interaction that varied with relative drought conditions. The presence or absence of antibodies in individual bats showed temporal variability. Year alone provided the best model to explain the likelihood of adult female bats showing a transition to seronegative from a previously seropositive state. Day of the season was the only competitive model to explain the likelihood of a transition from seronegative to seropositive, which increased as the season progressed. We found no rabies viral RNA in oropharyngeal secretions of 261 seropositive bats or in organs of 13 euthanized seropositive bats. Survival of seropositive and seronegative bats did not differ. The presence of RVNA in serum of bats should not be interpreted as evidence for ongoing rabies infection.
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Affiliation(s)
- Thomas J. O’Shea
- United States Geological Survey, Fort Collins Science Center, Fort Collins, Colorado, United States of America
- * E-mail:
| | - Richard A. Bowen
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Thomas R. Stanley
- United States Geological Survey, Fort Collins Science Center, Fort Collins, Colorado, United States of America
| | - Vidya Shankar
- Department of Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
- Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Charles E. Rupprecht
- Ross University School of Veterinary Medicine, Basseterre, Saint Kitts, West Indies
- The Global Alliance for Rabies Control, Manhattan, Kansas, United States of America
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Moeller KT, Butler MW, Denardo DF. The effect of hydration state and energy balance on innate immunity of a desert reptile. Front Zool 2013; 10:23. [PMID: 23642164 PMCID: PMC3660207 DOI: 10.1186/1742-9994-10-23] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 04/24/2013] [Indexed: 11/24/2022] Open
Abstract
Introduction Immune function is a vital physiological process that is often suppressed during times of resource scarcity due to investments in other physiological systems. While energy is the typical currency that has been examined in such trade-offs, limitations of other resources may similarly lead to trade-offs that affect immune function. Specifically, water is a critical resource with profound implications for organismal ecology, yet its availability can fluctuate at local, regional, and even global levels. Despite this, the effect of osmotic state on immune function has received little attention. Results Using agglutination and lysis assays as measures of an organism’s plasma concentration of natural antibodies and capacity for foreign cell destruction, respectively, we tested the independent effects of osmotic state, digestive state, and energy balance on innate immune function in free-ranging and laboratory populations of the Gila monster, Heloderma suspectum. This desert-dwelling lizard experiences dehydration and energy resource fluctuations on a seasonal basis. Dehydration was expected to decrease innate immune function, yet we found that dehydration increased lysis and agglutination abilities in both lab and field studies, a relationship that was not simply an effect of an increased concentration of immune molecules. Laboratory-based differences in digestive state were not associated with lysis or agglutination metrics, although in our field population, a loss of fat stores was correlated with an increase in lysis. Conclusions Depending on the life history of an organism, osmotic state may have a greater influence on immune function than energy availability. Thus, consideration of osmotic state as a factor influencing immune function will likely improve our understanding of ecoimmunology and the disease dynamics of a wide range of species.
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Affiliation(s)
- Karla T Moeller
- School of Life Sciences, Arizona State University, Tempe, AZ, USA.
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Johnstone CP, Reina RD, Lill A. Interpreting indices of physiological stress in free-living vertebrates. J Comp Physiol B 2012; 182:861-79. [PMID: 22415475 DOI: 10.1007/s00360-012-0656-9] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 02/22/2012] [Accepted: 02/24/2012] [Indexed: 10/28/2022]
Abstract
When vertebrate physiological ecologists use the terms 'stress' or 'physiological stress', they typically mean the level of hypothalamus-pituitary-adrenal (HPA-) axis activation. Measurements of stress hormone concentrations (e.g. glucocorticoids in blood, urine or faeces), leukocytes (e.g. the neutrophil-lymphocyte ratio or heterophil equivalent), immunofunction (e.g. innate, cell-mediated or humoral immunity measures) and regenerative anaemia (e.g. mean erythrocyte volume and red blood cell distribution width) have all been used to estimate HPA-axis activity in free-living vertebrates. Stress metrics have provided insights into aspects of autecology or population regulation that could not have been easily obtained using other indices of population wellbeing, such as body condition or relative abundance. However, short- and long-term stress (often problematically termed acute and chronic stress, respectively) can interact in unpredictable ways. When animals experience trapping and handling stress before blood, faeces and/or urine is sampled, the interaction of short- and long-term stress can confound interpretation of the data, a fact not always acknowledged in studies of stress in free-living vertebrates. This review examines how stress metrics can be confounded when estimates of HPA-axis activation are collected for free-living vertebrates and outlines some approaches that can be used to help circumvent the influence of potentially confounding factors.
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Affiliation(s)
- Christopher P Johnstone
- School of Biological Sciences, Monash University, Clayton Campus, Melbourne, VIC 3800, Australia.
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Does habitat fragmentation cause stress in the agile antechinus? A haematological approach. J Comp Physiol B 2011; 182:139-55. [PMID: 21710385 DOI: 10.1007/s00360-011-0598-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 06/12/2011] [Accepted: 06/16/2011] [Indexed: 10/18/2022]
Abstract
Although the vertebrate stress response is essential for survival, frequent or prolonged stress responses can result in chronic physiological stress, which is associated with a suite of conditions that can impair survivorship and reproductive output. Anthropogenic habitat fragmentation and degradation are potential stressors of free-living vertebrates, and in theory could result in chronic stress. To address this issue, we compared haematological indicators of stress and condition in agile antechinus (Antechinus agilis) populations in 30 forest fragments and 30 undisturbed, continuous forest sites (pseudofragments) in south-eastern Australia over 2 years. In peripheral blood, the total leucocyte count was lower and the neutrophil/lymphocyte ratio and percentage of eosinophils in the total leucocyte population was higher in fragment than pseudofragment populations, indicating that fragment populations were probably experiencing higher levels of stress hormone-mediated and/or parasite infection-related chronic physiological stress. The total erythrocyte count and haematocrit were higher and mean erythrocyte haemoglobin content was lower in fragment than pseudofragment populations. This suggests that fragment populations showed possible signs of regenerative anaemia, a syndrome associated with elevated hypothalamus-pituitary-adrenal axis mediated stress. However, mean erythrocyte volume was also lower in fragments, and red blood cell distribution width did not differ between the study populations, findings which were not consistent with this diagnosis. Whole blood and mean cell haemoglobin concentrations were similar in fragment and pseudofragment populations. We suggest that where anthropogenic activity results in habitat fragmentation and degradation, chronic stress could contribute to a decline in agile antechinus populations. The broader implication is that chronic stress could be both symptomatic of, and contributing to, decline of some vertebrate populations in anthropogenically fragmented and degraded habitats.
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