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Turko AJ, Firth BL, Craig PM, Eliason EJ, Raby GD, Borowiec BG. Physiological differences between wild and captive animals: a century-old dilemma. J Exp Biol 2023; 226:jeb246037. [PMID: 38031957 DOI: 10.1242/jeb.246037] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Laboratory-based research dominates the fields of comparative physiology and biomechanics. The power of lab work has long been recognized by experimental biologists. For example, in 1932, Georgy Gause published an influential paper in Journal of Experimental Biology describing a series of clever lab experiments that provided the first empirical test of competitive exclusion theory, laying the foundation for a field that remains active today. At the time, Gause wrestled with the dilemma of conducting experiments in the lab or the field, ultimately deciding that progress could be best achieved by taking advantage of the high level of control offered by lab experiments. However, physiological experiments often yield different, and even contradictory, results when conducted in lab versus field settings. This is especially concerning in the Anthropocene, as standard laboratory techniques are increasingly relied upon to predict how wild animals will respond to environmental disturbances to inform decisions in conservation and management. In this Commentary, we discuss several hypothesized mechanisms that could explain disparities between experimental biology in the lab and in the field. We propose strategies for understanding why these differences occur and how we can use these results to improve our understanding of the physiology of wild animals. Nearly a century beyond Gause's work, we still know remarkably little about what makes captive animals different from wild ones. Discovering these mechanisms should be an important goal for experimental biologists in the future.
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Affiliation(s)
- Andy J Turko
- Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada, N2L 3C5
| | - Britney L Firth
- Department of Biology, University of Waterloo, Waterloo, ON, Canada, N2L 3G1
| | - Paul M Craig
- Department of Biology, University of Waterloo, Waterloo, ON, Canada, N2L 3G1
| | - Erika J Eliason
- Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, Goleta, CA 93117, USA
| | - Graham D Raby
- Department of Biology, Trent University, Peterborough, ON, Canada, K9L 0G2
| | - Brittney G Borowiec
- Department of Biology, University of Waterloo, Waterloo, ON, Canada, N2L 3G1
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2
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Born-Torrijos A, Riekenberg P, van der Meer MTJ, Nachev M, Sures B, Thieltges DW. Parasite effects on host's trophic and isotopic niches. Trends Parasitol 2023; 39:749-759. [PMID: 37451950 DOI: 10.1016/j.pt.2023.06.003] [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: 03/08/2023] [Revised: 06/09/2023] [Accepted: 06/09/2023] [Indexed: 07/18/2023]
Abstract
Wild animals are usually infected with parasites that can alter their hosts' trophic niches in food webs as can be seen from stable isotope analyses of infected versus uninfected individuals. The mechanisms influencing these effects of parasites on host isotopic values are not fully understood. Here, we develop a conceptual model to describe how the alteration of the resource intake or the internal resource use of hosts by parasites can lead to differences of trophic and isotopic niches of infected versus uninfected individuals and ultimately alter resource flows through food webs. We therefore highlight that stable isotope studies inferring trophic positions of wild organisms in food webs would benefit from routine identification of their infection status.
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Affiliation(s)
- Ana Born-Torrijos
- Department of Coastal Systems, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands.
| | - Philip Riekenberg
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - Marcel T J van der Meer
- Department of Marine Microbiology and Biogeochemistry, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands
| | - Milen Nachev
- Department of Aquatic Ecology and Centre for Water and Environmental Research, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany
| | - Bernd Sures
- Department of Aquatic Ecology and Centre for Water and Environmental Research, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany; Research Center One Health Ruhr, Research Alliance Ruhr, University Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany
| | - David W Thieltges
- Department of Coastal Systems, NIOZ Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands; Groningen Institute for Evolutionary Life-Sciences, GELIFES, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands
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3
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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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Gomez SR, Morgans S, Kristan DM. Rapamycin exposure to host and to adult worms affects life history traits of Heligmosomoides bakeri. Exp Parasitol 2019; 204:107720. [PMID: 31279929 DOI: 10.1016/j.exppara.2019.107720] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 03/26/2019] [Accepted: 07/03/2019] [Indexed: 01/24/2023]
Abstract
Parasite life history can be affected by conditions of the host and of the external environment. Rapamycin, a known immunosuppressant of mammals, was fed to laboratory mice that were then infected with the Trichostrongylid nematode Heligmosomoides bakeri to determine if host rapamycin exposure would affect parasite survival, growth, and reproduction. In addition, adult worms from control fed mice were directly exposed to rapamycin to assess if rapamycin would affect worm viability and ex vivo reproduction. We found that host ingestion of rapamycin did not affect H. bakeri survival or growth for male or female worms, but female worms had increased reproduction both in vivo and when removed from the host and cultured ex vivo. After direct rapamycin exposure, motility of female worms was greater at low levels of rapamycin compared to high levels of rapamycin or high levels of DMSO (the vehicle used to solubilize rapamycin) in control media, but was similar to females in low levels of DMSO in control media. Male motility was not affected by the presence of rapamycin or DMSO in the media. Ex vivo egg deposition was higher when exposed to rapamycin than when cultured in control media that contained DMSO, regardless of DMSO dose. Overall, we conclude that host ingestion of rapamycin or direct exposure to rapamycin was generally favorable or neutral for parasite life history traits.
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Affiliation(s)
- Sarah R Gomez
- Department of Biological Sciences, 333 S. Twin Oaks Valley Rd, California State University San Marcos, San Marcos, CA, 92096, USA
| | - Scott Morgans
- Department of Biological Sciences, 333 S. Twin Oaks Valley Rd, California State University San Marcos, San Marcos, CA, 92096, USA
| | - Deborah M Kristan
- Department of Biological Sciences, 333 S. Twin Oaks Valley Rd, California State University San Marcos, San Marcos, CA, 92096, USA.
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Campbell L, Bower DS, Clulow S, Stockwell M, Clulow J, Mahony M. Interaction between temperature and sublethal infection with the amphibian chytrid fungus impacts a susceptible frog species. Sci Rep 2019; 9:83. [PMID: 30643160 PMCID: PMC6331562 DOI: 10.1038/s41598-018-35874-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 11/07/2018] [Indexed: 11/09/2022] Open
Abstract
The amphibian chytrid fungus Batrachochytrium dendrobatidis is an emerging infectious pathogen present on every continent except Antarctica. It causes the disease chytridiomycosis in a subset of species but does not always result in disease or death for every host. Ambient temperature influences both amphibian metabolism and chytrid pathogenicity, however the interactive effects on host physiology is not well understood. We investigated the sublethal effect of B. dendrobatidis infection on a susceptible host, Litoria aurea to test (1) whether the infection load, metabolic activity, body fat and gonad size differed in L. aurea at either 24 °C or 12 °C ambient temperatures and (2) whether previous Bd infection caused long-term changes to body fat and gonad size. Litoria aurea in 12 °C treatments had higher infection loads of B. dendrobatidis and lower survivorship. Metabolic rate was higher and fat mass was lower in infected individuals and in animals in 24 °C treatments. Male L. aurea previously infected with B. dendrobatidis had smaller testes 5 months-post clearance of infection, an effect likely to translate to fitness costs in wild populations. These experiments demonstrate a physiological cost to sublethal B. dendrobatidis infection, which suggests a reduction in host fitness mediated by temperature in the host's environment regardless of whether infection leads to mortality.
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Affiliation(s)
- Lachlan Campbell
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, Newcastle, 2300, NSW, Australia.
| | - Deborah S Bower
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, Newcastle, 2300, NSW, Australia.,James Cook University, Townsville, 4811, Qld, Australia
| | - Simon Clulow
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, Newcastle, 2300, NSW, Australia.,Department of Biological Sciences, Macquarie University, Sydney, NSW, 2109, Australia
| | - Michelle Stockwell
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, Newcastle, 2300, NSW, Australia
| | - John Clulow
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, Newcastle, 2300, NSW, Australia
| | - Michael Mahony
- School of Environmental and Life Sciences, University of Newcastle, Callaghan, Newcastle, 2300, NSW, Australia
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6
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Luong LT, Horn CJ, Brophy T. Mitey Costly: Energetic Costs of Parasite Avoidance and Infection. Physiol Biochem Zool 2017; 90:471-477. [DOI: 10.1086/691704] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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7
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Moretti EH, Titon B, Madelaire CB, de Arruda R, Alvarez T, Gomes FR. Behavioral, physiological and morphological correlates of parasite intensity in the wild Cururu toad ( Rhinella icterica). INTERNATIONAL JOURNAL FOR PARASITOLOGY-PARASITES AND WILDLIFE 2017; 6:146-154. [PMID: 28725553 PMCID: PMC5502792 DOI: 10.1016/j.ijppaw.2017.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 06/06/2017] [Accepted: 06/08/2017] [Indexed: 11/28/2022]
Abstract
Large numbers of parasites are found in various organs of anuran amphibians, with parasite intensities thought to modulate the host's Darwinian fitness traits. Interaction between the anuran hosts and their multiple parasites should modulate the host's phenotypic characteristic, such as those associated with high energetic demand (such as calling effort and locomotor performance), energy balance (standard metabolic rate), and morphological plasticity (as indicated by organ masses). The present study investigated the impact of parasite intensities on the behavioral, physiological, and morphological traits of wild adult male Rhinella icterica (Anura: Bufonidae). We tested as to whether individuals with higher parasite intensities would present: 1) lower vocal calling effort in the field, as well as poorer locomotor performance and body-condition index; and 2) higher standard metabolic rates and internal organ masses. Measurements included: calling effort in the field; standard metabolic rate; locomotor performance; parasite intensity; internal organ masses (heart, liver, kidneys, intestines, stomach, lungs, hind limb muscle, and spleen); and the body-condition index. Results showed a negative association of parasite intensities with locomotor performance, and standard metabolic rate of R. icterica. A positive association between parasite intensities and relative organ masses (heart, intestines and kidneys) was also evident. Toads with higher pulmonary and intestinal parasites intensities also showed higher total parasite intensities.
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Affiliation(s)
- Eduardo Hermógenes Moretti
- Departamento de Fisiologia, Instituto de Biociências, Universidade Estadual Paulista "Júlio de Mesquita Filho", Rua Prof. Dr. Antônio Celso Wagner Zanin, s/n, 18618-689, Botucatu, SP, Brazil
| | - Braz Titon
- Departamento de Fisiologia, Instituto de Biociências, Universidade Estadual Paulista "Júlio de Mesquita Filho", Rua Prof. Dr. Antônio Celso Wagner Zanin, s/n, 18618-689, Botucatu, SP, Brazil
| | - Carla Bonetti Madelaire
- Departamento de Fisiologia, Instituto de Biociências, Universidade Estadual Paulista "Júlio de Mesquita Filho", Rua Prof. Dr. Antônio Celso Wagner Zanin, s/n, 18618-689, Botucatu, SP, Brazil
| | - Raquel de Arruda
- Departamento de Fisiologia, Instituto de Biociências, Universidade Estadual Paulista "Júlio de Mesquita Filho", Rua Prof. Dr. Antônio Celso Wagner Zanin, s/n, 18618-689, Botucatu, SP, Brazil
| | - Tatiana Alvarez
- Departamento de Fisiologia, Instituto de Biociências, Universidade Estadual Paulista "Júlio de Mesquita Filho", Rua Prof. Dr. Antônio Celso Wagner Zanin, s/n, 18618-689, Botucatu, SP, Brazil
| | - Fernando Ribeiro Gomes
- Departamento de Fisiologia, Instituto de Biociências, Universidade Estadual Paulista "Júlio de Mesquita Filho", Rua Prof. Dr. Antônio Celso Wagner Zanin, s/n, 18618-689, Botucatu, SP, Brazil
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8
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Gupta N, Gupta DK, Sharma PK. Condition factor and organosomatic indices of parasitized Rattus rattus as indicators of host health. J Parasit Dis 2017; 41:21-28. [PMID: 28316383 DOI: 10.1007/s12639-015-0744-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Accepted: 10/07/2015] [Indexed: 11/30/2022] Open
Abstract
This study describes the influence of parasitism (Trypanosoma lewisi and Cysticercus fasciolaris) on the condition factor, hepato and splenosomatic indices of the common house rat, Rattus rattus Linnaeus, 1758 from Rohilkhand, Uttar Pradesh, India. Examination of R. rattus (n = 389) revealed T. lewisi (prevalence 12.40 %; intensity14 parasites/1000 RBC) from the blood and C. fasciolaris (larval Taenia taeniaeformis) (prevalence 46.70 %; intensity 2-4 par/host) from the liver. Condition factor (K) and organosomatic indices [hepatosomatic index, spleenosomatic index (SSI)] were evaluated in two groups (Group I non pregnant, Group II pregnant) of female rats which were further subdivided into four subgroups each (a Uninfected, b T. lewisi infected, c C. fasciolaris infected, d T. lewisi and C. fasciolaris infected) belonging to three weight groups (A 50-100 g; B 100-150 g; C 150-200 g). The results indicated that reduction in K-factor was more apparent in young rats, Group Ic (weight category A) showing the maximum depletion (21.62 %), hepatomegaly and splenomegaly were frequent outcomes of parasitic infection and maximum change (50 %) was recorded in dual-infected pregnant rats (Group IId) expressed as SSI of the infected rat. The abnormal condition factor and organosomatic indices indicate perturbations in the biological systems at the organismal level. Thus, the information generated through this piece of work is a warning of an incipient or impending problem.
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Affiliation(s)
- Neelima Gupta
- Centre of Excellence Laboratory, Department of Animal Science, M.J.P. Rohilkhand University, Bareilly, 243 006 U.P. India
| | - D K Gupta
- Department of Zoology, Bareilly College, Bareilly, 243 005 U.P. India
| | - P K Sharma
- Centre of Excellence Laboratory, Department of Animal Science, M.J.P. Rohilkhand University, Bareilly, 243 006 U.P. India
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Orlofske SA, Belden LK, Hopkins WA. Effects of Echinostoma trivolvis metacercariae infection during development and metamorphosis of the wood frog (Lithobates sylvaticus). Comp Biochem Physiol A Mol Integr Physiol 2016; 203:40-48. [PMID: 27543422 DOI: 10.1016/j.cbpa.2016.08.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 07/28/2016] [Accepted: 08/05/2016] [Indexed: 11/27/2022]
Abstract
Many organisms face energetic trade-offs between defense against parasites and other host processes that may determine overall consequences of infection. These trade-offs may be particularly evident during unfavorable environmental conditions or energetically demanding life history stages. Amphibian metamorphosis, an ecologically important developmental period, is associated with drastic morphological and physiological changes and substantial energetic costs. Effects of the trematode parasite Echinostoma trivolvis have been documented during early amphibian development, but effects during later development and metamorphosis are largely unknown. Using a laboratory experiment, we examined the energetic costs of late development and metamorphosis coupled with E. trivolvis infection in wood frogs, Lithobates [=Rana] sylvaticus. Echinostoma infection intensity did not differ between tadpoles examined prior to and after completing metamorphosis, suggesting that metacercariae were retained through metamorphosis. Infection with E. trivolvis contributed to a slower growth rate and longer development period prior to the initiation of metamorphosis. In contrast, E. trivolvis infection did not affect energy expenditure during late development or metamorphosis. Possible explanations for these results include the presence of parasites not interfering with pronephros degradation during metamorphosis or the mesonephros compensating for any parasite damage. Overall, the energetic costs of metamorphosis for wood frogs were comparable to other species with similar life history traits, but differed from a species with a much shorter duration of metamorphic climax. Our findings contribute to understanding the possible role of energetic trade-offs between parasite defense and host processes by considering parasite infection with simultaneous energetic demands during a sensitive period of development.
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Affiliation(s)
- Sarah A Orlofske
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA.
| | - Lisa K Belden
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061, USA
| | - William A Hopkins
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA
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10
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Time budget, oxygen consumption and body mass responses to parasites in juvenile and adult wild rodents. Parasit Vectors 2016; 9:120. [PMID: 26932152 PMCID: PMC4774152 DOI: 10.1186/s13071-016-1407-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 02/24/2016] [Indexed: 12/03/2022] Open
Abstract
Background The study of changes in a host’s energy allocation in response to parasites is crucial for understanding parasite impact on both individual- and population-level processes. Experimental studies have explored such responses mainly in a single subsample of hosts per study, primarily adult males, and have only assessed either the overall energy acquisition or expenditure, rather than their different components simultaneously, or the behavioral responses. Accordingly, two fundamental questions arise: why have multiple host strategies evolved to cope with increased energy expenditure? and, which factors determine this variation (e.g. host species, identity, age)? This study provides an important step towards addressing both questions by experimentally disentangling the short-term physiological and behavioral responses of juvenile and non-reproductive adult rodents to natural levels of flea infestation. These two cohorts represent extreme cases of the energy demand continuum, as the former, in contrast to the latter, is involved in growth - a highly energy-demanding process - and may not be able to operate far below its upper limit of energy expenditure, and thus should reduce its energy expenses upon the occurrence of extra demands (e.g. due to parasitic pressure). Accordingly, we hypothesized that the response to fleas is age-dependent and varies according to the age-specific energy requirements and constraints. Methods We monitored the behavior and physiology of juvenile and non-reproductive adult rodents before and after experimental flea infestation. First, we used a model selection approach to search for the factors that best explained the variability in the time budget, oxygen consumption, and body mass change in response to fleas. Then, using a path analysis approach, we quantified the different pathways connecting the important associations revealed at stage 1. Results Compared to their flea-free counterparts, flea-infested adults groomed longer and had a higher oxygen consumption rate, but did not lose body mass. Infested juveniles also groomed longer but grew slower and had a similar rate of oxygen consumption. Conclusions Results suggest that both juvenile and adult rodents suffer from natural flea infestation levels. However, the comparison between the responses of juveniles and adults to experimental infestation, also suggests that juveniles may reallocate their energy expenditure from growth to maintenance, while non-reproductive adults increase their energy acquisition. Such age-dependent responses suggest that juveniles may be constrained by their higher need to rest for full functioning or by an upper limit in energy expenditure. Taken together, our study provides experimental evidence that hosts can compensate for the costs incurred by parasitism through physiological and behavioral plasticity, depending on their age, which probably determines their requirements and constraints. These compensatory responses may have important implications for the population dynamics of hosts and their parasites.
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Novikov E, Kondratyuk E, Petrovski D, Krivopalov A, Moshkin M. Effects of parasites and antigenic challenge on metabolic rates and thermoregulation in northern red-backed voles (Myodes rutilus). Parasitol Res 2015; 114:4479-86. [DOI: 10.1007/s00436-015-4691-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 08/24/2015] [Indexed: 01/09/2023]
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12
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Robertson LM, Alley MR, Gartrell BD, Castro IC, Lopez-Villalobos N, Sancha E. Efficacy of anthelmintic treatment in captive-reared black stilts (Himantopus novaezelandiae) released to the wild. N Z Vet J 2015. [PMID: 26208464 DOI: 10.1080/00480169.2015.1073636] [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: 10/23/2022]
Abstract
AIMS To assess the efficacy of praziquantel (PZQ) administered to control helminths in captive-reared critically endangered black stilts (Himantopus novaezelandiae) before their release into the wild and determine the effect on their survival shortly after release. METHODS Of 77 captive black stilts, 37 were treated with PZQ prior to release into the wild in South Canterbury, New Zealand, in August and September 2007. Faecal helminth egg counts (FEC) were measured before and after anthelmintic treatment, and before and after release to the wild using modified faecal flotation and sedimentation methods. In addition, total helminth counts were determined in 11 of the birds that died following release, as well as four captive and 11 other wild stilts. RESULTS The efficacy of PZQ against trematodes was 92% and against Capillaria spp. was 34%. No trematode or Capillaria spp. eggs were detected in treated birds 1 day after treatment, but FEC increased 3-5 days after treatment. There were no differences in the total helminth counts for trematodes, cestodes or Capillaria spp. in control or treated birds (p>0.2). Survival did not differ between treatment groups in the August or September releases (p>0.4). Of control and treated birds, 11/17 (65%) and 8/14 (57%) survived to 31 days, respectively, in the August release, and 16/20 (80%) and 10/15 (67%) survived to 84 days, respectively, in the September release. CONCLUSION Overall, the results suggest that PZQ treatment may be an unnecessary cost and the risks of producing anthelmintic resistance, injuring the birds during processing or producing an unnecessary stress response at the time of release could exceed any likely benefits. CLINICAL RELEVANCE It is recommended that pre-release anthelmintic treatment of black stilts should be used only if indicated by health screening. Any treatment should incorporate annual efficacy testing to monitor the emergence of anthelmintic resistance.
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Affiliation(s)
- L M Robertson
- a Institute of Natural Resources , Massey University , Private Bag 11222, Palmerston North 4474 , New Zealand
| | - M R Alley
- b Wildbase, Institute of Veterinary, Animal and Biomedical Sciences , Massey University , Private Bag 11222, Palmerston North 4474 , New Zealand
| | - B D Gartrell
- b Wildbase, Institute of Veterinary, Animal and Biomedical Sciences , Massey University , Private Bag 11222, Palmerston North 4474 , New Zealand
| | - I C Castro
- a Institute of Natural Resources , Massey University , Private Bag 11222, Palmerston North 4474 , New Zealand
| | - N Lopez-Villalobos
- b Wildbase, Institute of Veterinary, Animal and Biomedical Sciences , Massey University , Private Bag 11222, Palmerston North 4474 , New Zealand
| | - E Sancha
- c Department of Conservation , Private Bag, Twizel 7901 , New Zealand
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13
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Krams IA, Krama T, Moore FR, Kivleniece I, Kuusik A, Freeberg TM, Mänd R, Rantala MJ, Daukšte J, Mänd M. Male mealworm beetles increase resting metabolic rate under terminal investment. J Evol Biol 2014; 27:541-50. [DOI: 10.1111/jeb.12318] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Revised: 12/10/2013] [Accepted: 12/10/2013] [Indexed: 12/15/2022]
Affiliation(s)
- I. A. Krams
- Institute of Systematic Biology; University of Daugavpils; Daugavpils Latvia
- Institute of Ecology and Earth Sciences; University of Tartu; Tartu Estonia
- Department of Biology; University of Turku; Turku Finland
| | - T. Krama
- Institute of Systematic Biology; University of Daugavpils; Daugavpils Latvia
| | - F. R. Moore
- School of Psychology; University of Dundee; Dundee UK
| | - I. Kivleniece
- Institute of Systematic Biology; University of Daugavpils; Daugavpils Latvia
| | - A. Kuusik
- Department of Plant Protection; Institute of Agricultural and Environmental Sciences; Estonian University of Life Science; Tartu Estonia
| | - T. M. Freeberg
- Department of Psychology and Department of Ecology and Evolutionary Biology; University of Tennessee; Knoxville TN USA
| | - R. Mänd
- Institute of Ecology and Earth Sciences; University of Tartu; Tartu Estonia
| | - M. J. Rantala
- Department of Biology; University of Turku; Turku Finland
| | - J. Daukšte
- Institute of Food Safety; Animal Health and Environment “BIOR”; Riga Latvia
| | - M. Mänd
- Department of Plant Protection; Institute of Agricultural and Environmental Sciences; Estonian University of Life Science; Tartu Estonia
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14
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Xu YC, Yang DB, Speakman JR, Wang DH. Oxidative stress in response to natural and experimentally elevated reproductive effort is tissue dependent. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12168] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Yan-Chao Xu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents; Institute of Zoology; Chinese Academy of Sciences; Beijing 100101 China
- University of Chinese Academy of Sciences; Beijing 100049 China
| | - Deng-Bao Yang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents; Institute of Zoology; Chinese Academy of Sciences; Beijing 100101 China
- University of Chinese Academy of Sciences; Beijing 100049 China
| | - John R. Speakman
- State Key Laboratory of Molecular Developmental Biology; Institute of Genetics and Developmental Biology; Chinese Academy of Sciences; Beijing 100101 China
- Institute of Biological and Environmental Sciences; University of Aberdeen; Aberdeen AB24 2TZ UK
| | - De-Hua Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents; Institute of Zoology; Chinese Academy of Sciences; Beijing 100101 China
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15
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Gamo Y, Troup C, Mitchell SE, Hambly C, Vaanholt LM, Speakman JR. Limits to sustained energy intake. XX. Body temperatures and physical activity of female mice during lactation. ACTA ACUST UNITED AC 2013; 216:3751-61. [PMID: 23788704 DOI: 10.1242/jeb.090308] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Lactating animals consume greater amounts of food than non-reproductive animals, but energy intake appears to be limited in late lactation. The heat dissipation limit theory suggests that the food intake of lactating mice is limited by the capacity of the mother to dissipate heat. Lactating mice should therefore have high body temperatures (Tb), and changes in energy intake during lactation should be reflected by variation in Tb. To investigate these predictions, 26 mice (Mus musculus) were monitored daily throughout lactation for food intake, body mass, litter size and litter mass. After weaning, 21 days postpartum, maternal food intake and body mass were monitored for another 10 days. Maternal activity and Tb were recorded every minute for 23 h a day using implanted transmitters (vital view). Energy intake increased to a plateau in late lactation (days 13-17). Daily gain in pup mass declined during this same period, suggesting a limit on maternal energy intake. Litter size and litter mass were positively related to maternal energy intake and body mass. Activity levels were constantly low, and mice with the largest increase in energy intake at peak lactation had the lowest activity. Tb rose sharply after parturition and the circadian rhythm became compressed within a small range. Tb during the light period increased considerably (1.1 ° C higher than in baseline), and lactating mice faced chronic hyperthermia, despite their activity levels in lactation being approximately halved. Average Tb increased in relation to energy intake as lactation progressed, but there was no relationship between litter size or litter mass and the mean Tb at peak lactation. These data are consistent with the heat dissipation limit theory, which suggests performance in late lactation is constrained by the ability to dissipate body heat.
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Affiliation(s)
- Y Gamo
- Institute of Biological and Environmental Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
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16
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Orlofske S, Belden L, Hopkins W. Larval wood frog (Rana [=Lithobates] sylvatica) development and physiology following infection with the trematode parasite, Echinostoma trivolvis. Comp Biochem Physiol A Mol Integr Physiol 2013; 164:529-36. [DOI: 10.1016/j.cbpa.2012.12.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Revised: 12/11/2012] [Accepted: 12/13/2012] [Indexed: 11/25/2022]
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17
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Order of Inoculation during Heligmosomoides bakeri and Hymenolepis microstoma Coinfection Alters Parasite Life History and Host Responses. Pathogens 2013; 2:130-52. [PMID: 25436885 PMCID: PMC4235709 DOI: 10.3390/pathogens2010130] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 02/02/2013] [Accepted: 02/21/2013] [Indexed: 11/24/2022] Open
Abstract
Parasite life history may differ during coinfection compared to single infections, and the order of infection may be an important predictor of life history traits. We subjected laboratory mice (Mus musculus) to single and coinfections with Heligmosomoides bakeri and Hymenolepis microstoma and measured life history traits of worms and also hepatobiliary and morphological responses by the host. We found that fewer H. bakeri larvae established, and adult worms were shorter and produced fewer eggs during a coinfection where H. microstoma occurred first. H. microstoma grew more and released more eggs after simultaneous inoculation of both parasites compared to a single H. microstoma infection, despite similar worm numbers. Mouse small intestine mass, but not length, varied with coinfection and bile duct mass was largest when H. microstoma was given alone or first. Mouse serum alkaline phosphatase levels were greatest for mice infected with H. microstoma only but did not vary with number of scolices; no change in mouse serum alanine transaminase levels was observed. Overall, the order of coinfection influenced life history traits of both H. bakeri and H. microstoma, but changes in survival, growth, and reproduction with order of inoculation were not consistent between the two parasites.
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Lutermann H, Bodenstein C, Bennett NC. Natural parasite infection affects the tolerance but not the response to a simulated secondary parasite infection. PLoS One 2012; 7:e52077. [PMID: 23300593 PMCID: PMC3531392 DOI: 10.1371/journal.pone.0052077] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 11/15/2012] [Indexed: 01/15/2023] Open
Abstract
Parasites deplete the resources of their host and can consequently affect the investment in competing traits (e.g. reproduction and immune defence). The immunocompetence handicap hypothesis posits that testosterone (T) mediates trade-offs between parasite defence and reproductive investment by suppressing immune function in male vertebrates while more recently a role for glucocorticoids (e.g. cortisol (C)) in resource allocation has been suggested. These hypotheses however, have not always found support in wild animals, possibly because most studies focus on a single parasite species, whereas infections with multiple parasites are the rule in nature. We measured body mass, T- and C-levels of wild male highveld mole-rats (Cryptomys hottentotus pretoriae) naturally uninfected or infected with a cestode (Mathevotaenia sp.) right after capture. Subsequently, we injected animals subcutaneously with a lipopolysaccharide (LPS) to simulate a bacterial infection and recorded changes in body mass, food intake, haematological parameters and hormone levels. As a control, animals were injected with saline. Natural infection neither affected initial body mass nor C-levels, whereas infected males had significantly reduced T-levels. We observed significant reductions in food intake, body mass and T in response to LPS but not saline while C increased. However, this response did not vary with infection status. In contrast, final body mass and some haematological parameters were significantly lowered in infected males. Our results suggest that naturally infected males are able to compensate for resource depletion by physiological adjustments. However, this leaves them less tolerant to the challenges of a secondary infection.
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Affiliation(s)
- Heike Lutermann
- Department of Zoology and Entomology, University of Pretoria, Private Bag X20, Hatfield, South Africa.
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POLLOCK NICHOLASB, VREDEVOE LARISAK, TAYLOR EMILYN. The Effect of Exogenous Testosterone on Ectoparasite Loads in Free-Ranging Western Fence Lizards. ACTA ACUST UNITED AC 2012; 317:447-54. [DOI: 10.1002/jez.1737] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Revised: 04/03/2012] [Accepted: 04/25/2012] [Indexed: 11/12/2022]
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20
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Hawley DM, DuRant SE, Wilson AF, Adelman JS, Hopkins WA. Additive metabolic costs of thermoregulation and pathogen infection. Funct Ecol 2012. [DOI: 10.1111/j.1365-2435.2012.01978.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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21
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Kolluru GR, Green ZS, Vredevoe LK, Kuzma MR, Ramadan SN, Zosky MR. Parasite infection and sand coarseness increase sand crab (Emerita analoga) burrowing time. Behav Processes 2011; 88:184-91. [PMID: 21959036 DOI: 10.1016/j.beproc.2011.09.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Revised: 09/09/2011] [Accepted: 09/13/2011] [Indexed: 11/26/2022]
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22
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Robar N, Murray DL, Burness G. Effects of parasites on host energy expenditure: the resting metabolic rate stalemate. CAN J ZOOL 2011. [DOI: 10.1139/z11-084] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Detrimental effects of parasitism on host fitness are frequently attributed to parasite-associated perturbations to host energy budgets. It has therefore been widely hypothesized that energetic costs of infection may be manifest as changes in host resting metabolic rate (RMR). Attempts to quantify these effects have yielded contradictory results across host–parasite systems. We used a meta-analysis of the literature to test the effects of parasites on mass-specific (n = 22) and whole-body (n = 15) host RMR. Parasites resulted in a qualitative increase in host RMR in the majority of studies; however, the overall effect of parasites on host RMR was small and statistically nonsignificant. Additionally, substantial among-study variation in host RMR could not be explained by any of the tested covariates. We conclude that the lack of an overall effect of parasites on host metabolism reflects inconsistent directionality and varying magnitudes of parasite-associated effects across studies, rather than an absence of system-specific effects. We contend that a general understanding of parasite effects on host energetics may be best achieved through identifying mechanisms underlying among-system variance in parasite effects on host RMR and relating parasite-associated perturbations of host energy budgets to robust estimates of host fitness.
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Affiliation(s)
- Nicholas Robar
- Environmental and Life Sciences Graduate Program, Trent University, 1600 West Bank Drive, Peterborough, ON K9J 7B8, Canada
| | - Dennis L. Murray
- Department of Biology, Trent University, Peterborough, ON K9J 7B8, Canada
| | - Gary Burness
- Department of Biology, Trent University, Peterborough, ON K9J 7B8, Canada
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Dietary protein and energy supplies differentially affect resistance to parasites in lactating mammals. Br J Nutr 2011; 106:1207-15. [PMID: 21736817 DOI: 10.1017/s0007114511001565] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Periparturient relaxation of immunity (PPRI) to parasites in mammals results in higher worm burden and worm egg excretion and may have a nutritional basis. Nippostrongylus brasiliensis re-infected lactating rats fed low-crude protein (CP) diets show an augmented degree of PPRI compared with their high CP-fed counterparts. However, such effects of CP scarcity have been confounded by metabolisable energy (ME) scarcity due to increased intake of the high-CP foods. Here, we independently assessed the effects of dietary CP and ME scarcity on the degree of PPRI. Second, parity rats were infected with N. brasiliensis larvae before mating. Upon parturition, dams were allocated to one of six feeding treatments (1-6), consisting of two levels of dietary ME supply, each with three levels of CP supply. On day 2 of lactation, dams were either re-infected with 1600 N. brasiliensis larvae or sham-infected with PBS, while litter size was standardised at ten pups. Dams and litters were weighed daily until either day 8 or 11 of lactation, when worm burdens were assessed as a proxy for PPRI. Increased CP and ME supply independently improved lactational performance. While ME supply did not affect parasitism, increasing CP supply reduced worm burden and the percentage of female worms in the small intestine; the latter was especially pronounced at the lower level of ME supply. The present results support the view that PPRI to parasites may be sensitive to CP scarcity, but not to moderate ME scarcity.
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Scantlebury M, Maher McWilliams M, Marks NJ, Dick JTA, Edgar H, Lutermann H. Effects of life-history traits on parasite load in grey squirrels. J Zool (1987) 2010. [DOI: 10.1111/j.1469-7998.2010.00734.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Mallitt KL, Bonser SP, Hunt J. The plasticity of phenotypic integration in response to light and water availability in the pepper grass, Lepidium bonariense. Evol Ecol 2010. [DOI: 10.1007/s10682-010-9373-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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26
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Devevey G, Bize P, Fournier S, Person E, Christe P. Testing the predictive adaptive response in a host-parasite system. Funct Ecol 2010. [DOI: 10.1111/j.1365-2435.2009.01609.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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27
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Concurrent nematode infection and pregnancy induce physiological responses that impair linear growth in the murine foetus. Parasitology 2009; 137:991-1002. [DOI: 10.1017/s0031182009991764] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
SUMMARYThis study examined concurrent stresses of nematode infection and pregnancy using pregnant and non-pregnant CD1 mice infected 3 times with 0, 50 or 100 Heligmosomoides bakeri larvae. Physiological, energetic, immunological and skeletal responses were measured in maternal and foetal compartments. Resting metabolic rate (RMR) was elevated by pregnancy, but not by the trickle infection. Energy demands during pregnancy were met through increased food intake and fat utilization whereas mice lowered their body temperature during infection. Both infection and pregnancy increased visceral organ mass and both altered regional bone area and mineralization. During pregnancy, lumbar mineralization was lower but femur area and mineralization were higher. On the other hand, infection lowered maternal femur bone area and this was associated with higher IFN-γ in maternal serum of heavily infected pregnant mice. Infection also reduced foetal crown-rump length which was associated with higher amniotic fluid IL-1β.
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28
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Orlofske SA, Belden LK, Hopkins WA. Moderate Echinostoma trivolvis Infection Has No Effects on Physiology and Fitness-Related Traits of Larval Pickerel Frogs (Rana palustris). J Parasitol 2009; 95:787-92. [DOI: 10.1645/ge-1840.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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29
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Devevey G, Niculita-Hirzel H, Biollaz F, Yvon C, Chapuisat M, Christe P. Developmental, metabolic and immunological costs of flea infestation in the common vole. Funct Ecol 2008. [DOI: 10.1111/j.1365-2435.2008.01493.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Tu T, Phillips AT, Koski KG, Scott ME. Acute phase nematode infection reduces resting metabolic rate in both protein-sufficient and protein-deficient mice. CAN J ZOOL 2008. [DOI: 10.1139/z08-123] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The objective of this study was to investigate whether protein deficiency concurrent with the acute phase of infection with the murine nematode Heligmosomoides bakeri (Durette-Desset, Kinsella and Forrester, 1972; Tenora and Barus, 2001) affected the resting metabolic rate (RMR) in BALB/c mice, and whether deworming caused RMR to return to normal. Mice fed either a protein-sufficient (PS, 24%) or protein-deficient (PD, 3%) diet were infected with 100 larvae, and then treated with an anthelmintic drug on 9 and 14 days postinfection (dpi). RMR was measured on –2, 2, 7, and 19 dpi. The results showed that protein deficiency did not affect RMR at any of these times. RMR was unchanged immediately following infection (2 vs. –2 dpi) at the time when larvae are first embedded in the serosal musculture. Surprisingly, at 7 dpi when larvae migrate from the serosal musculture into the intestinal lumen, RMR was significantly lower in both diet groups compared with earlier time points. This reduced RMR persisted even after deworming. Possible reasons for these results are discussed.
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Affiliation(s)
- T. Tu
- School of Dietetics and Human Nutrition, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, QC H9X 3V9, Canada
- Institute of Parasitology, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, QC H9X 3V9, Canada
| | - A. T. Phillips
- School of Dietetics and Human Nutrition, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, QC H9X 3V9, Canada
- Institute of Parasitology, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, QC H9X 3V9, Canada
| | - K. G. Koski
- School of Dietetics and Human Nutrition, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, QC H9X 3V9, Canada
- Institute of Parasitology, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, QC H9X 3V9, Canada
| | - M. E. Scott
- School of Dietetics and Human Nutrition, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, QC H9X 3V9, Canada
- Institute of Parasitology, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, QC H9X 3V9, Canada
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Abstract
The strength of the immune response and the outcome of the interaction of a host with a parasite are influenced by genetic and phenotypic characteristics of both parties, and by environmental variables. Allocation of host resources to immune defence reduces resources available for other life-history traits. This review identifies six potential costs to the host from immune activation. The costs are likely to be broadly applicable to other immune responses in vertebrate species. Five phenotypic costs arise from: (i) increased metabolic activity; (ii) reduced nutrient availability due to anorexia; (iii) altered priorities for nutrient utilization; (iv) change in size and turnover of pools of immune cells and proteins; and (v) immunopathology from inappropriate or excessive immune activation. Subsumed by these costs is the cost of altered efficiency of nutrient use. A sixth cost is the genetic cost which arises from a change in the capacity of offspring to express production and life-history traits following selection for parasite resistance. The sensitivity of immune responses to the phenotypic status of the host, and the role the immune system shares with the neuroendocrine system in controlling use of resources underpin the importance of immunocompetence to the life-history of the host.
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Affiliation(s)
- I G Colditz
- CSIRO Livestock Industries, F.D. McMaster Laboratory, Armidale NSW, Australia.
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32
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COX ROBERTM, JOHN-ALDER HENRYB. Increased mite parasitism as a cost of testosterone in male striped plateau lizards Sceloporus virgatus. Funct Ecol 2007. [DOI: 10.1111/j.1365-2435.2007.01251.x] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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33
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Püttker T, Meyer-Lucht Y, Sommer S. Effects of fragmentation on parasite burden (nematodes) of generalist and specialist small mammal species in secondary forest fragments of the coastal Atlantic Forest, Brazil. Ecol Res 2007. [DOI: 10.1007/s11284-007-0366-z] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Tu T, Koski KG, Wykes LJ, Scott ME. Re-feeding rapidly restores protection againstHeligmosomoides bakeri(Nematoda) in protein-deficient mice. Parasitology 2007; 134:899-909. [PMID: 17288635 DOI: 10.1017/s0031182007002314] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
SUMMARYThis study determined whether the timing of re-feeding of protein-deficient mice restored functional protection against the gastrointestinal nematode,Heligmosomoides bakeri. Balb/c mice were fed a 3% protein-deficient (PD) diet and then transferred to 24% protein-sufficient (PS) diet either on the day of primary infection, 10 days after the primary infection, on the day of challenge infection, or 7 days after the challenge infection. Control mice were fed either the PD or PS diet. Onset of challenge, but not primary, infection caused short-term body weight loss, anorexia and reduced feed efficiency. Weight gain was delayed in mice when re-feeding commenced on the day of challenge infection; alkaline phosphatase (ALP) was also elevated in these mice on day 28 post-challenge. In contrast, other re-feeding groups attained similar body weights to PS mice within 4 days and had similar ALP at day 28. Serum leptin was higher in PD than PS mice and positively associated with food intake. As expected, worm survival was prolonged in mice fed the PD diet. However, egg production and worm burdens were similar in all re-feeding groups to the PS mice, indicating that protein re-feeding during either the primary or challenge infection rapidly restored normal parasite clearance.
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Affiliation(s)
- T Tu
- School of Dietetics and Human Nutrition, Institute of Parasitology, McGill University (Macdonald Campus), 21 111 Lakeshore Road, Ste-Anne de Bellevue, Quebec H9X 3V9, Canada
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35
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Schwanz LE. Schistosome infection in deer mice (Peromyscus maniculatus):impacts on host physiology, behavior and energetics. J Exp Biol 2006; 209:5029-37. [PMID: 17142691 DOI: 10.1242/jeb.02601] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
SUMMARY
Animals routinely encounter environmental stressors and may employ phenotypic plasticity to compensate for the costs of these perturbations. Parasites represent an ecologically important stressor for animals, which may induce host plasticity. The present study examined the effects of a trematode parasite, Schistosomatium douthitti, on deer mouse (Peromyscus maniculatus) physiology, behavior and energetics. Measures were taken to assess direct parasite pathology as well as potential host plasticity used to reduce the costs of these pathologies. Parasitized mice had increased liver and spleen masses, as well as decreased liver protein synthesis. Parasitism also led to increased gastrointestinal (GI) mass, either directly due to parasite presence or as host compensation for decreased GI function. No additional plasticity was recorded - infected animals did not consume more food, decrease in body mass or reduce their activity. Parasitism led to reduced thermoregulation during short-term cold exposure, indicating that there may be fitness costs of parasitism. There were no changes in the other measures of energetics taken here, namely basal metabolic rate (BMR) and cold-induced maximal metabolic rate (MRmax). Together, the results suggest that many costs of parasite infection are largely ameliorated through physiological or morphological compensatory mechanisms.
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Affiliation(s)
- Lisa E Schwanz
- Department of Biology, University of New Mexico, Albuquerque, NM 87109, USA.
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36
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Brown T, Fuller C. Stress and parasitism of white-footed mice (Peromyscus leucopus) in dry and floodplain environments. CAN J ZOOL 2006. [DOI: 10.1139/z06-183] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We hypothesized that flooding represents an environmental stressor that might affect the corticosterone levels, parasite prevalence, and life history of small mammals living in floodplain environments. We compared populations of white-footed mice ( Peromyscus leucopus (Rafinesque, 1818)) on floodplains and dry areas. We found more males on floodplains (p = 0.008) and more females on dry areas (p = 0.005). There were no differences in mass (p > 0.05) or intestinal parasite prevalence (p = 0.665) between dry and floodplain habitats, but bot fly larvae were significantly more prevalent in males living on floodplains (p = 0.043). Floodplain animals had significantly higher levels of corticosterone than dry-area animals in fall, and lower levels in summer (F[1,20] = 4.483, p = 0.047). In addition, we found that animals with intestinal parasites had higher levels of corticosterone than those that were without parasites (p = 0.014) or that harbored bot fly larvae (p = 0.001). Floodplains seem to be harsher environments than dry areas, but this may be a result of differences in habitat rather than a direct result of flooding.
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Affiliation(s)
- T.T. Brown
- Department of Biological Sciences, Murray State University, 334 Blackburn Hall, Murray, KY 42071, USA
| | - C.A. Fuller
- Department of Biological Sciences, Murray State University, 334 Blackburn Hall, Murray, KY 42071, USA
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37
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Magnanou E, Fons R, Feliu C, Morand S. Physiological responses of insular wild black rat (Rattus rattus) to natural infection by the digenean trematode Fasciola hepatica. Parasitol Res 2006; 99:97-101. [PMID: 16470416 DOI: 10.1007/s00436-005-0063-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Accepted: 10/14/2005] [Indexed: 11/29/2022]
Abstract
Wild black rat Rattus rattus is regularly infected by the liver fluke Fasciola hepatica on Corsica. This report constitutes the only example of a murid rodent that plays an important epidemiological role for the Fasciolosis. We investigated the influence of such unusual parasite infection on black rat physiology by measuring its oxygen consumption at different ambient temperatures. Black rat energy requirements are influenced by body mass, temperature of the experiment and parasite infestation. The influence of the presence of F. hepatica was more pronounced for cold temperatures. The mean increase of 56% in oxygen requirements for infected rats is extremely high, indeed unexpected, according to previous knowledge. These high physiological constraints may be explained by the recent confrontation of the digenean and the rodent.
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Affiliation(s)
- E Magnanou
- Centre d'Ecologie Evolutive, UMR 7628 CNRS-Université Pierre et Marie Curie Observatoire Océanologique de Banyuls sur Mer-Laboratoire Arago BP 44, 66 651, Banyuls sur mer Cedex, France.
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Kristan DM, Hammond KA. Effects of three simultaneous demands on glucose transport, resting metabolism and morphology of laboratory mice. J Comp Physiol B 2006; 176:139-51. [PMID: 16416287 DOI: 10.1007/s00360-005-0036-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2005] [Revised: 08/11/2005] [Accepted: 09/29/2005] [Indexed: 10/25/2022]
Abstract
In nature, animals must successfully respond to many simultaneous demands from their environment in order to survive and reproduce. We examined physiological and morphological responses of mice given three demands: intestinal parasite infection with Heligmosomoides polygyrus followed by caloric restriction (70% of ad libitum food intake versus ad libitum for 10 days) and/or cold exposure (5 degrees C vs. 23 degrees C for 10 days). We found significant interactions between these demands as well as independent effects. Small intestine structure and function changed with demands in both independent and interactive ways. Body mass decreased during caloric restriction and this decrease was greater for cold-exposed than warm-exposed mice. In ad libitum fed mice, body mass did not change with either cold exposure or parasite infection but body composition (fat versus lean mass of whole body or organs) changed with both demands. Generally, organ masses decreased with caloric restriction (even after accounting for body mass effects) and increased with cold exposure and parasite infection whereas fat mass decreased with both caloric restriction and parasite infection. Mass adjusted resting metabolic rate (RMR) increased with cold exposure, decreased with caloric restriction but, unlike previous studies with laboratory mice, did not change with parasite infection. Our results demonstrate that the ability of mice to respond to a demand is influenced by other concurrent demands and that mice show phenotypic plasticity of morphological and physiological features ranging from the tissue level to the level of the whole organism when given three simultaneous demands.
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Affiliation(s)
- Deborah M Kristan
- Department of Biology, University of California, Riverside, CA 92521, USA.
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Magnanou E, Fons R, Blondel J, Morand S. Energy expenditure in Crocidurinae shrews (Insectivora): Is metabolism a key component of the insular syndrome? Comp Biochem Physiol A Mol Integr Physiol 2005; 142:276-85. [PMID: 16154371 DOI: 10.1016/j.cbpb.2005.07.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2005] [Revised: 07/13/2005] [Accepted: 07/14/2005] [Indexed: 10/25/2022]
Abstract
A cascade of morphological, ecological, demographical and behavioural changes operates within island communities compared to mainland. We tested whether metabolic rates change on islands. Using a closed circuit respirometer, we investigated resting metabolic rate (RMR) of three species of Crocidurinae shrews: Suncus etruscus, Crocidura russula, and C. suaveolens. For the latter, we compared energy expenditure of mainland and island populations. Our measurements agree with those previously reported for others Crocidurinae: the interspecific comparison (ANCOVA) demonstrated an allometric relation between energy requirements and body mass. Energy expenditure also scaled with temperature. Island populations (Corsica and Porquerolles) of C. suaveolens differed in size from mainland (gigantism). A GLM showed a significant relationship between energy expenditure, temperature, body mass and locality. Mass specific RMR allometrically scales body mass, but total RMR does not significantly differ between mainland and island, although island shrews are giant. Our results are consistent with other studies: that demonstrated that the evolution of mammalian metabolism on islands is partially independent of body mass. In relation to the insular syndrome, we discuss how island selective forces (changes in resource availability, decrease in competition and predation pressures) can operate in size and physiological adjustments.
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Affiliation(s)
- Elodie Magnanou
- Centre d'Ecologie Evolutive, UMR 7628 CNRS, Université Pierre et Marie Curie, Observatoire Océanologique de Banyuls sur Mer, Laboratoire Arago, BP 44, 66 651 Banyuls sur mer Cedex, France.
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THOMPSON ROSSM, MOURITSEN KIMN, POULIN ROBERT. Importance of parasites and their life cycle characteristics in determining the structure of a large marine food web. J Anim Ecol 2004. [DOI: 10.1111/j.1365-2656.2004.00899.x] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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WILLIAMS CM, POULIN R, SINCLAIR BJ. Increased haemolymph osmolality suggests a new route for behavioural manipulation of Talorchestia quoyana (Amphipoda: Talitridae) by its mermithid parasite. Funct Ecol 2004. [DOI: 10.1111/j.0269-8463.2004.00910.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kristan DM, Hammond KA. Morphological plasticity varies with duration of infection: evidence from lactating and virgin wild-derived house mice (Mus musculus) infected with an intestinal parasite (Heligmosomoides polygyrus; Nematoda). ACTA ACUST UNITED AC 2004; 207:2351-60. [PMID: 15159439 DOI: 10.1242/jeb.01020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
With chronic parasite infection, host response to the parasite may change throughout the duration of the infection as the host progresses from the acute to the chronic phase. We investigated the effects of parasite infection ranging in duration from 30 to 120 days on host morphology both alone and in combination with lactation by using captive wild-derived house mice (Mus musculus) experimentally infected with a naturally occurring intestinal nematode (Heligmosomoides polygyrus). We found that some changes in host morphology were greatest at 30-60 days post-infection (e.g. spleen mass) followed by a decline towards the control state whereas other morphological changes were greatest at 90-120 days post-infection (e.g. small intestine mass) after a relatively steady increase with infection duration. For all infection durations, the morphological responses to parasite infection were similar for virgin and lactating mice (except for lean body mass). After accounting for changes in body mass with lactation, lactating mice increased organs of the gastrointestinal tract as well as liver and kidney but had less body fat than virgin mice. This is the first study to demonstrate that morphological plasticity of mice parasitized by H. polygyrus varies with infection duration and that this variation is generally similar for lactating and virgin mice.
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Affiliation(s)
- Deborah M Kristan
- Department of Biology, University of California, Riverside, CA 92521, USA.
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Kristan DM, Hammond KA. Aerobic Performance of Wild‐Derived House Mice Does Not Change with Cold Exposure or Intestinal Parasite Infection. Physiol Biochem Zool 2004; 77:440-9. [PMID: 15286917 DOI: 10.1086/383513] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2003] [Indexed: 11/03/2022]
Abstract
Aerobic performance is affected by numerous endogenous and exogenous factors. We investigated the effects of ambient temperature and parasite infection on resting metabolism and maximal exercise-induced oxygen consumption in wild-derived house mice (Mus musculus). We also collected preliminary data for effects of lactation on these measures of aerobic performance. Mice were experimentally infected with a naturally occurring intestinal nematode (Heligmosomoides polygyrus) and then exposed to cold temperatures for 10 d or allowed to mate and reproduce. Wild-derived house mice did not change their resting metabolism with H. polygyrus infection or cold exposure, which is in stark contrast to similar studies with laboratory mice. Preliminary data also showed no effect of lactation on aerobic performance. Similarly, maximal exercise-induced oxygen consumption and hematocrit and hemoglobin were unaffected by all experimental treatments. We conclude that resting metabolism, maximal oxygen consumption, and hematology of wild-derived house mice are unaffected by exogenous (temperature) and endogenous (H. polygyrus) demands and, therefore, wild-derived mice respond to these demands without incurring potential costs associated with changes in aerobic performance.
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Affiliation(s)
- Deborah M Kristan
- Department of Biology, University of California, Riverside, California 92521, USA.
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Kristan DM. Intestinal nematode infection affects host life history and offspring susceptibility to parasitism. J Anim Ecol 2004. [DOI: 10.1111/j.0021-8790.2004.00794.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Heitman TL, Koski KG, Scott ME. Energy deficiency alters behaviours involved in transmission ofHeligmosomoides polygyrus(Nematoda) in mice. CAN J ZOOL 2003. [DOI: 10.1139/z03-168] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Independent studies have shown that animal behaviour is affected by nutritional deficiency and that host behaviour influences parasite transmission. The objectives of this study were to determine whether energy deficiency alters the behaviour profile of mice and the rate of exposure of mice to naturally acquired Heligmosomoides polygyrus (Nematoda) larvae. Outbred CF-1 and CD-1 female mice were fed either a control or an energy-deficient (65% of control) diet for 7 days, after which time, the mice fed the deficient diet had consumed signficantly less energy, had lower rectal temperatures, and lower masses (CD-1 mice only) compared with control mice. On day 7, mice were placed individually in natural transmission arenas containing damp peat moss and parasite larvae for 6 h, during which time, each mouse was observed 60 times and her behaviour recorded. All mice were then returned to standard caging and fed the energy-sufficient diets to eliminate confounding effects of energy deficiency on the host immune response over the following 8 days. At necropsy, parasite numbers were significantly lower in the energy-deficient mice of both strains. The behaviour profile differed significantly between diet groups and between strains; deficient mice of both strains groomed less and dug in the peat substrate less than control mice. The frequency of grooming was positively correlated with worm burden in both strains, the frequency of mouthing the peat moss and of sleeping were positively associated with worm burden in CD-1 mice, and the frequency of standing and walking low was positively associated with worm burden in CF-1 mice. These results indicate that grooming and contact with the peat moss are important behaviours in transmission of H. polygyrus, that energy deficiency causes a decrease in the frequency of these behaviours, and that these behavioural changes may contribute to reduced parasite transmission in mice fed the energy-restricted diet.
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Stein RW, Williams TD. Tissue Damage Precludes the Use of the Everted Sleeve Technique to Measure Nutrient Uptake in a Small Migratory Shorebird, the Western Sandpiper (Calidris mauri). Physiol Biochem Zool 2003; 76:762-70. [PMID: 14671723 DOI: 10.1086/376426] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2003] [Indexed: 11/03/2022]
Affiliation(s)
- R Will Stein
- Centre for Wildlife Ecology, Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S6, Canada.
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Kristan DM, Hammond KA. Physiological and morphological responses to simultaneous cold exposure and parasite infection by wild-derived house mice. Funct Ecol 2003. [DOI: 10.1046/j.1365-2435.2003.00751.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
An important question about traditional caloric restriction (CR) experiments on laboratory mice is how food intake in the laboratory compares with that of wild mice in nature. Such knowledge would allow us to distinguish between two opposing views of the anti-aging effect of CR--whether CR represents, in laboratory animals, a return to a more normal level of food intake, compared with excess food consumption typical of laboratory conditions or whether CR represents restriction below that of animals living in nature, i.e. the conditions under which house mice evolved. To address this issue, we compared energy use of three mouse genotypes: (1) laboratory-selected mouse strains (= laboratory mice), (2) house mice that were four generations or fewer removed from the wild (= wild-derived mice) and (3) mice living in nature (= wild mice). We found, after correcting for body mass, that ad libitum fed laboratory mice eat no more than wild mice. In fact, under demanding natural conditions, wild mice eat even more than ad libitum fed laboratory mice. Laboratory mice do, however, eat more than wild-derived mice housed in similar captive conditions. Therefore, laboratory mice have been selected during the course of domestication for increased food intake compared with captive wild mice, but they are not particularly gluttonous compared with wild mice in nature. We conclude that CR experiments do in fact restrict energy consumption beyond that typically experienced by mice in nature. Therefore, the retarded aging observed with CR is not due to eliminating the detrimental effects of overeating.
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Affiliation(s)
- Steven N Austad
- University of Idaho, Department of Biological Sciences, Moscow, ID 83844-3051, USA.
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Kristan DM. Effects of intestinal nematodes during lactation: consequences for host morphology, physiology and offspring mass. J Exp Biol 2002; 205:3955-65. [PMID: 12432017 DOI: 10.1242/jeb.205.24.3955] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARYSublethal parasites are often assumed to have no detrimental effects on their host. However, the sublethal intestinal nematode Heligmosomoides polygyrus affects both the morphology and the physiology of its laboratory mouse (Mus musculus) host and therefore has the potential to affect host life history. The objectives of the present study were to determine (1) whether lactating and non-lactating mice responded similarly to experimental infection with H. polygyrus and (2) whether the changes in morphology and physiology that occurred with parasite infection affected host reproductive performance. Parasitized mice had greater whole body mass as a result of greater lean mass compared with unparasitized mice. Parasitized mice had larger organs (spleen, stomach, cecum and small intestine) and a diminished rate of glucose transport by the small intestine compared with unparasitized mice. Lactating mice had larger organs (liver, kidney, spleen,heart, stomach, large intestine, cecum and small intestine), lean mass and whole body mass, but a similar rate of glucose transport compared with virgin mice. Resting metabolism increased with lactation but not with parasitism. Lactating and non-lactating mice responded similarly to parasite infection for most measured variables. Production of large litters was followed by production of small litters for parasitized but not unparasitized females. After adjusting for parity and litter size, parasitized mothers produced female pups that were 6% smaller at weaning than female pups from unparasitized mothers, but there was no effect of maternal parasite infection on mass at weaning for male pups. Other measures of reproductive output were not affected by parasite infection.
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Affiliation(s)
- Deborah M Kristan
- Department of Biology, University of California, Riverside 92521, USA.
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Kristan DM. Maternal and direct effects of the intestinal nematode Heligmosomoides polygyrus on offspring growth and susceptibility to infection. J Exp Biol 2002; 205:3967-77. [PMID: 12432018 DOI: 10.1242/jeb.205.24.3967] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
The laboratory mouse (Mus musculus) has a naturally occurring intestinal nematode (Heligmosomoides polygyrus) that induces an immune response, causes phenotypic plasticity in metabolism and in organ structure and function, and results in changes in host reproductive output. The objectives of the present study were to determine (1) whether pups infected with parasites at weaning grew differently and had a different body composition at adulthood compared with uninfected pups, (2) whether offspring from parasitized mothers grew differently and had a different body composition at adulthood compared with offspring from unparasitized mothers, (3) whether parasite effects on body composition of pups varied under different infection intensities and (4) whether maternal parasite infection affected susceptibility, duration and intensity of offspring parasite infection. H. polygyrus had direct and maternal effects on offspring growth, but final adult mass was not affected by parasites. Parasite infection in offspring had no effect on overall fat mass, but mass changes for some organs were greater for mice that had a high infection intensity compared with mice that had a low infection intensity. Only offspring from parasitized mothers cleared their parasite infection; however, if the infection was not cleared, the final infection intensity was greater for offspring born to parasitized mothers than to unparasitized mothers. This study shows that chronic, sublethal parasite infection with H. polygyrus has both maternal and direct effects that induce physiological changes in growing mice sufficient to alter host growth trajectories, morphology and susceptibility to parasite infection.
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Affiliation(s)
- Deborah M Kristan
- Department of Biology, University of California, Riverside 92521, USA.
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