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Zhang L, Tang X, Fan C, Ren S, Cheng Q, Zhou H, Liu K, Jia S, Zhang Y. Dysbiosis of Gut Microbiome Aggravated Male Infertility in Captivity of Plateau Pika. Biomolecules 2024; 14:403. [PMID: 38672421 PMCID: PMC11047922 DOI: 10.3390/biom14040403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 03/15/2024] [Accepted: 03/20/2024] [Indexed: 04/28/2024] Open
Abstract
Captivity is an important and efficient technique for rescuing endangered species. However, it induces infertility, and the underlying mechanism remains obscure. This study used the plateau pika (Ochotona curzoniae) as a model to integrate physiological, metagenomic, metabolomic, and transcriptome analyses and explore whether dysbiosis of the gut microbiota induced by artificial food exacerbates infertility in captive wild animals. Results revealed that captivity significantly decreased testosterone levels and the testicle weight/body weight ratio. RNA sequencing revealed abnormal gene expression profiles in the testicles of captive animals. The microbial α-diversity and Firmicutes/Bacteroidetes ratio were drastically decreased in the captivity group. Bacteroidetes and Muribaculaceae abundance notably increased in captive pikas. Metagenomic analysis revealed that the alteration of flora increased the capacity for carbohydrate degradation in captivity. The levels of microbe metabolites' short-chain fatty acids (SCFAs) were significantly high in the captive group. Increasing SCFAs influenced the immune response of captivity plateau pikas; pro-inflammatory cytokines were upregulated in captivity. The inflammation ultimately contributed to male infertility. In addition, a positive correlation was observed between Gastranaerophilales family abundance and testosterone concentration. Our results provide evidence for the interactions between artificial food, the gut microbiota, and male infertility in pikas and benefit the application of gut microbiota interference in threatened and endangered species.
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Affiliation(s)
- Liangzhi Zhang
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China; (L.Z.); (X.T.); (C.F.); (S.R.); (Q.C.)
| | - Xianjiang Tang
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China; (L.Z.); (X.T.); (C.F.); (S.R.); (Q.C.)
| | - Chao Fan
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China; (L.Z.); (X.T.); (C.F.); (S.R.); (Q.C.)
| | - Shi’en Ren
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China; (L.Z.); (X.T.); (C.F.); (S.R.); (Q.C.)
| | - Qi Cheng
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China; (L.Z.); (X.T.); (C.F.); (S.R.); (Q.C.)
| | - Huakun Zhou
- Key Laboratory of Restoration Ecology of Cold Area in Qinghai Province, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China;
| | - Kai Liu
- Qinghai Provincial Grassland Station, Xining 810008, China;
| | - Shangang Jia
- College of Grassland Science and Technology, China Agricultural University, Beijing 100193, China
| | - Yanming Zhang
- Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China; (L.Z.); (X.T.); (C.F.); (S.R.); (Q.C.)
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2
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Beattie UK, Rosen ES, Fefferman N, Romero LM. House sparrows prioritize skin repair over constitutive innate immunity during long-term chronic stress. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2023; 339:464-473. [PMID: 36918745 DOI: 10.1002/jez.2692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 02/08/2023] [Accepted: 03/01/2023] [Indexed: 03/16/2023]
Abstract
The reactive scope model was created to address two major unanswered questions in stress physiology: how and when does the adaptive acute stress response turn into harmful chronic stress? Previous studies suggest that immunoenhancement should occur in reactive homeostasis (acute stress) and immunosuppression should occur in homeostatic overload (chronic stress). We used this dichotomy of immune function to further elucidate the transition from acute to chronic stress by treating house sparrows (Passer domesticus) with different intensities of chronic stress and then monitoring their immune function. By varying the number of stressors given per day and the length of chronic stress bouts over a period of 6 months, we produced four treatment groups: high, medium, and low stress, and captivity-only. We tracked immunity through the bacterial killing assay and monitored healing of a 4 mm skin biopsy punch. We hypothesized that higher-stress birds would repair their skin more slowly and have lower bacterial killing capacity. The opposite was true-high-stress birds initially repaired their skin fastest. Additionally, all birds dramatically reduced bacterial killing capacity after the biopsy and increased food-derived uric acid, suggesting increased energy acquisition and a shift in immune resources to a more immediate concern (healing). Once healing finished, only the high-stress birds were unable to recover circulating immune function, suggesting that the combination of high stress and an immune challenge pushed these birds into homeostatic overload. Prioritizing healing over other immunological processes might be the best defense for a bird in its natural habitat.
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Affiliation(s)
- Ursula K Beattie
- Department of Biology, Tufts University, Massachusetts, Medford, USA
| | - Emma S Rosen
- Department of Biology, Tufts University, Massachusetts, Medford, USA
| | - Nina Fefferman
- Department of Ecology and Evolutionary Biology and Department of Mathematics, University of Tennessee, Tennessee, Knoxville, USA
| | - L Michael Romero
- Department of Biology, Tufts University, Massachusetts, Medford, USA
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3
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Padrones MN, Cid FD, Chediack JG. Effects of corticosterone administration on the body condition and blood parameters of the house sparrow, Passer domesticus. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2023; 339:369-382. [PMID: 36772870 DOI: 10.1002/jez.2683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 12/15/2022] [Accepted: 01/12/2023] [Indexed: 02/12/2023]
Abstract
Glucocorticoids are steroid hormones produced by the adrenal glands and released into the bloodstream in response to stressful situations. In birds, corticosterone (CORT) is the main glucocorticoid released under stress. Throughout their lives, animals in nature are continually exposed to noxious stimuli known as stressful events. Any alteration of homeostatic stability is a stressful situation and this alteration triggers physiological changes to restore homeostasis. Glucocorticoids are one of the components of the complex set of physiological and behavioral responses to stress. In this work, we use CORT supplied in drinking water to evaluate its effect in blood parameters and physiology in house sparrows (Passer domesticus). To accomplish this, P. domesticus were administered three different doses of CORT in drinking water for 72 h. Body mass, organ mass, pectoral muscle mass, leg muscle mass, and blood parameters (CORT, triglycerides, glucose and uric acid, heterophils/lymphocytes ratio, hematocrit, and serum protein profile) were determined before and after CORT treatment. A 15% decrease in body mass with a significant decrease in pectoral mass were observed after the higher CORT treatment, as well as a decrease in the plasma concentration of uric acid. Lastly, we found a reversal of the heterophils/lymphocytes ratio and a decrease in hematocrit. It was possible to establish first data for baseline and CORT-alteration values in serum protein profile for P. domesticus. Baseline and altered values of blood parameters and serum protein profile could be an important tool in field ecology because they provide important data to assess the physiological condition in wild birds.
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Affiliation(s)
- Marcelo N Padrones
- Laboratorio de Biología Integrativa, Instituto Multidisciplinario de Investigaciones Biológicas de San Luis (IMIBIO-SL), CONICET, San Luis, Argentina
- Área de Biología, Departamento de Biología, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina
| | - Fabricio D Cid
- Laboratorio de Biología Integrativa, Instituto Multidisciplinario de Investigaciones Biológicas de San Luis (IMIBIO-SL), CONICET, San Luis, Argentina
- Área de Biología, Departamento de Biología, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina
| | - Juan G Chediack
- Laboratorio de Biología Integrativa, Instituto Multidisciplinario de Investigaciones Biológicas de San Luis (IMIBIO-SL), CONICET, San Luis, Argentina
- Área de Biología, Departamento de Biología, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, San Luis, Argentina
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4
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Martin LB, Ruhs EC, Oakey S, Downs CJ. Leukocyte allometries in birds are not affected by captivity. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2022; 337:576-582. [PMID: 35286769 DOI: 10.1002/jez.2591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 01/17/2022] [Accepted: 02/11/2022] [Indexed: 12/15/2022]
Abstract
Body size affects many traits, but often in allometric, or disproportionate ways. For example, large avian and mammalian species circulate far more of some immune cells than expected for their size based on simple geometric principles. To date, such hypermetric immune scaling has mostly been described in zoo-dwelling individuals, so it remains obscure whether immune hyper-allometries have any natural relevance. Here, we asked whether granulocyte and lymphocyte allometries in wild birds differ from those described in captive species. Our previous allometric studies of avian immune cell concentrations were performed on animals kept for their lifetimes in captivity where conditions are benign and fairly consistent. In natural conditions, infection, stress, nutrition, climate, and myriad other forces could alter immune traits and hence mask any interspecific scaling relationships between immune cells and body size. Counter to this expectation, we found no evidence that immune cell allometries differed between captive and wild species, although we had to rely on cell proportion data, as insufficient concentration data were available for wild species. Our results indicate that even in variable and challenging natural contexts, immune allometries endure and might affect disease ecology and evolution.
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Affiliation(s)
- Lynn B Martin
- Global Health and Infectious Disease Research, University of South Florida, Tampa, Florida, USA
| | - Emily Cornelius Ruhs
- Global Health and Infectious Disease Research, University of South Florida, Tampa, Florida, USA
| | - Samantha Oakey
- Global Health and Infectious Disease Research, University of South Florida, Tampa, Florida, USA
| | - Cynthia J Downs
- Department of Environmental and Forest Biology, SUNY College of Environmental Science and Forestry, Syracuse, New York, USA
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5
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Madden AA, Oliverio AM, Kearns PJ, Henley JB, Fierer N, Starks PTB, Wolfe BE, Romero LM, Lattin CR. Chronic stress and captivity alter the cloacal microbiome of a wild songbird. J Exp Biol 2022; 225:274791. [DOI: 10.1242/jeb.243176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Accepted: 03/07/2022] [Indexed: 11/20/2022]
Abstract
There are complex interactions between an organism's microbiome and its response to stressors, often referred to as the “gut-brain axis;” however, the ecological relevance of this axis in wild animals remains poorly understood. Here, we used a chronic mild stress protocol to induce stress in wild-caught house sparrows (Passer domesticus), and compared microbial communities among stressed animals, those recovering from stress, captive controls (unstressed), and a group not brought into captivity. We assessed changes in microbial communities and abundance of shed microbes by culturing cloacal samples on multiple media to select for aerobic and anaerobic bacteria and fungi. We complemented this with cultivation-independent 16S and ITS rRNA gene amplification and sequencing, pairing these results with host physiological and immune metrics, including body mass change, relative spleen mass, and plasma corticosterone concentrations. We found significant effects of stress and captivity on the house sparrow microbiomes, with stress leading to an increased relative abundance of endotoxin-producing bacteria— a possible mechanism for the hyperinflammatory response observed in captive avians. While we found evidence that the microbiome community partially recovers after stress cessation, animals may lose key taxa, and the abundance of endotoxin-producing bacteria persists. Our results suggest an overall link between chronic stress, host immune system, and the microbiome, with the loss of potentially beneficial taxa (e.g., lactic acid bacteria), and an increase in endotoxin-producing bacteria due to stress and captivity. Ultimately, consideration of the host's microbiome may be useful when evaluating the impact of stressors on individual and population health.
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Affiliation(s)
- Anne A. Madden
- Department of Biology, Tufts University, Medford, MA 02155, USA
- The Microbe Institute, Everett, MA, 02149, USA
| | - Angela M. Oliverio
- Department of Soil and Crop Sciences, Colorado State University, Fort Collins, Colorado, USA
- Yale School of the Environment, Yale University, 195 Prospect St., New Haven, CT, 06511, USA
| | | | - Jessica B. Henley
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA
| | - Noah Fierer
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado, USA
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, USA
| | | | | | | | - Christine R. Lattin
- Department of Biology, Tufts University, Medford, MA 02155, USA
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
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6
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Cutrera AP, Luna F, Zenuto RR. Acute-Phase Immune Response Involves Fever, Sickness Behavior, and an Elevated Metabolic Rate in the Subterranean Rodent Ctenomys talarum. Physiol Biochem Zool 2022; 95:183-199. [PMID: 35148257 DOI: 10.1086/718409] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
AbstractThe acute-phase response (APR) is an induced innate response and may involve pronounced physiological and behavioral changes. One of the most common assays to study the APR involves the use of a lypopolysaccharide (LPS) from the cell wall of gram-negative bacteria. In this study, we determined the energetic costs of the APR in the subterranean rodent Ctenomys talarum, as well as the effects of the exposure to LPS on body temperature, body mass loss, and behavior in this species. Furthermore, we monitored levels of circulating endotoxin after LPS exposure. Our results suggest that in C. talarum, the APR is energetically costly, resulting in a 14% increase in metabolic rate. Animals exposed to LPS experienced a short-term thermal response, weight loss, and changes in their behavior that included more time spent resting and with their eyes totally or partially closed. However, the magnitude of the effects of LPS exposure varied between sexes and among animals. Also, there was a clear peak in circulating endotoxin levels in plasma 3 h postinjection (hpi) and a significant decrease of these levels 24 hpi, but peak endotoxin concentration values recorded were highly variable among animals. In light of these results, ecological determinants of immune function variation in tuco-tucos are discussed considering the roles of pace of life, habitat, and degree of pathogen exposure in these subterranean rodents.
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7
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Zimmer C, Hanson HE, Martin LB. FKBP5 expression is related to HPA flexibility and the capacity to cope with stressors in female and male house sparrows. Horm Behav 2021; 135:105038. [PMID: 34280702 DOI: 10.1016/j.yhbeh.2021.105038] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 07/06/2021] [Accepted: 07/08/2021] [Indexed: 12/16/2022]
Abstract
The hypothalamic-pituitary-adrenal (HPA) axis and its end products, the glucocorticoids, are critical to responding appropriately to stressors. Subsequently, many studies have sought relationships between glucocorticoids and measures of health or fitness, but such relationships are at best highly context dependent. Recently, some endocrinologists have started to suggest that a focus on HPA flexibility, the ability of an individual to mount appropriate responses to different stressors, could be useful. Here, we tested the hypothesis that expression of FKBP5, a cochaperone in the glucocorticoid receptor complex, is a simple and reliable proxy of HPA flexibility in a wild songbird, the house sparrow (Passer domesticus). We quantified HPA flexibility in a novel way, using guidance from research on heart rhythm regulation. As predicted, we found that adult sparrows with low stress-induced FKBP5 expression in the hypothalamus exhibited high HPA flexibility. Moreover, low FKBP5 expression was associated with greater exploratory disposition and were better at maintaining body mass under stressful conditions. Altogether, these results suggest that FKBP5 may be important in the regulation of HPA flexibility, potentially affecting how individuals cope with natural and anthropogenic adversity.
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Affiliation(s)
- Cedric Zimmer
- Global Health and Infectious Disease Research, University of South Florida, Tampa, FL, USA.
| | - Haley E Hanson
- Global Health and Infectious Disease Research, University of South Florida, Tampa, FL, USA
| | - Lynn B Martin
- Global Health and Infectious Disease Research, University of South Florida, Tampa, FL, USA
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8
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Hanson HE, Zimmer C, Koussayer B, Schrey AW, Maddox JD, Martin LB. Epigenetic potential affects immune gene expression in house sparrows. J Exp Biol 2021; 224:224/6/jeb238451. [PMID: 33775934 DOI: 10.1242/jeb.238451] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 02/06/2021] [Indexed: 12/15/2022]
Abstract
Epigenetic mechanisms may play a central role in mediating phenotypic plasticity, especially during range expansions, when populations face a suite of novel environmental conditions. Individuals may differ in their epigenetic potential (EP; their capacity for epigenetic modifications of gene expression), which may affect their ability to colonize new areas. One form of EP, the number of CpG sites, is higher in introduced house sparrows (Passer domesticus) than in native birds in the promoter region of a microbial surveillance gene, Toll-like Receptor 4 (TLR4), which may allow invading birds to fine-tune their immune responses to unfamiliar parasites. Here, we compared TLR4 gene expression from whole blood, liver and spleen in house sparrows with different EP, first challenging some birds with lipopolysaccharide (LPS), to increase gene expression by simulating a natural infection. We expected that high EP would predict high inducibility and reversibility of TLR4 expression in the blood of birds treated with LPS, but we did not make directional predictions regarding organs, as we could not repeatedly sample these tissues. We found that EP was predictive of TLR4 expression in all tissues. Birds with high EP expressed more TLR4 in the blood than individuals with low EP, regardless of treatment with LPS. Only females with high EP exhibited reversibility in gene expression. Further, the effect of EP varied between sexes and among tissues. Together, these data support EP as one regulator of TLR4 expression.
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Affiliation(s)
- Haley E Hanson
- University of South Florida, Global Health and Infectious Disease Research, Tampa, FL 33612, USA
| | - Cedric Zimmer
- University of South Florida, Global Health and Infectious Disease Research, Tampa, FL 33612, USA
| | - Bilal Koussayer
- University of South Florida, Global Health and Infectious Disease Research, Tampa, FL 33612, USA
| | - Aaron W Schrey
- Georgia Southern University Armstrong Campus, Department of Biology, Savannah, GA 31419, USA
| | - J Dylan Maddox
- Field Museum of Natural History, 1400 S. Lake Shore Drive, Chicago, IL 60605, USA.,American Public University System, Environmental Sciences, Charles Town, WV 25414, USA.,Universidad Científica del Perú, Laboratorio de Biotecnología y Bioenergética, Iquitos 16007, Perú
| | - Lynn B Martin
- University of South Florida, Global Health and Infectious Disease Research, Tampa, FL 33612, USA
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Abstract
Whilst the immune system often varies seasonally and exhibits differences between males and females, the general patterns in seasonality and sex differences across taxa have remained controversial. Birds are excellent model organisms to assess these patterns, because the immune system of many species is well characterised. We conducted a meta-analysis using 41 wild bird species from 24 avian families to investigate sex differences and seasonal (breeding/non-breeding) variations in immune status, including white blood cell counts, phytohaemagglutinin (PHA) test, bacteria-killing ability (BKA), haemolysis and haemagglutination assays. We found male-biased macrophage concentration, BKA and haemolysis titers, but only during the breeding season. Sex-specific heterophil concentrations, heterophil/lymphocyte ratios and PHA responses differed between breeding and non-breeding, suggesting larger changes in males than in females. Importantly, sex differences in immune status are stronger during the breeding period than during the non-breeding period. Taken together, our study suggests that both seasonal variation and sex differences in immune system are common in birds, although their associations are more complex than previously thought.
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10
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Gormally BMG, Romero LM. What are you actually measuring? A review of techniques that integrate the stress response on distinct time‐scales. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13648] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Hanson HE, Koussayer B, Kilvitis HJ, Schrey AW, Maddox JD, Martin LB. Epigenetic Potential in Native and Introduced Populations of House Sparrows (Passer domesticus). Integr Comp Biol 2020; 60:1458-1468. [PMID: 32497186 DOI: 10.1093/icb/icaa060] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Epigenetic potential, defined as the capacity for epigenetically-mediated phenotypic plasticity, may play an important role during range expansions. During range expansions, populations may encounter relatively novel challenges while experiencing lower genetic diversity. Phenotypic plasticity via epigenetic potential might be selectively advantageous at the time of initial introduction or during spread into new areas, enabling introduced organisms to cope rapidly with novel challenges. Here, we asked whether one form of epigenetic potential (i.e., the abundance of CpG sites) in three microbial surveillance genes: Toll-like receptors (TLRs) 1B (TLR1B), 2A (TLR2A), and 4 (TLR4) varied between native and introduced house sparrows (Passer domesticus). Using an opportunistic approach based on samples collected from sparrow populations around the world, we found that introduced birds had more CpG sites in TLR2A and TLR4, but not TLR1B, than native ones. Introduced birds also lost more CpG sites in TLR1B, gained more CpG sites in TLR2A, and lost fewer CpG sites in TLR4 compared to native birds. These results were not driven by differences in genetic diversity or population genetic structure, and many CpG sites fell within predicted transcription factor binding sites (TFBS), with losses and gains of CpG sites altering predicted TFBS. Although we lacked statistical power to conduct the most rigorous possible analyses, these results suggest that epigenetic potential may play a role in house sparrow range expansions, but additional work will be critical to elucidating how epigenetic potential affects gene expression and hence phenotypic plasticity at the individual, population, and species levels.
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Affiliation(s)
- Haley E Hanson
- Global and Planetary Health, University of South Florida, 3720 Spectrum Blvd, Suite 304, Tampa, FL 33620, USA
| | - Bilal Koussayer
- Global and Planetary Health, University of South Florida, 3720 Spectrum Blvd, Suite 304, Tampa, FL 33620, USA
| | - Holly J Kilvitis
- Department of Integrative Biology, University of South Florida, 4202 E. Fowler Ave, SCA110, Tampa, FL 33620, USA
| | - Aaron W Schrey
- Department of Biology, Georgia Southern University, Armstrong Campus, 11935 Abercorn St, SC1010, Savannah, GA 31419, USA
| | - J Dylan Maddox
- Field Museum of Natural History, 1400 S. Lake Shore Drive, Chicago, IL 60605, USA.,Laboratorio de Biotecnología y Bioenergética, Universidad Científica del Perú, Iquitos, Perú.,American Public University System, Environmental Sciences, Charles Town, WV 25414, USA
| | - Lynn B Martin
- Global and Planetary Health, University of South Florida, 3720 Spectrum Blvd, Suite 304, Tampa, FL 33620, USA
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12
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Gardner ST, Assis VR, Smith KM, Appel AG, Mendonça MT. Innate immunity of Florida cane toads: how dispersal has affected physiological responses to LPS. J Comp Physiol B 2020; 190:317-327. [PMID: 32189063 DOI: 10.1007/s00360-020-01272-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 02/24/2020] [Accepted: 03/02/2020] [Indexed: 12/21/2022]
Abstract
Physiological tradeoffs occur in organisms coping with their environments, which are likely to increase as populations reach peripheries of established ranges. Invasive species offer opportunities to study tradeoffs that occur, with many hypotheses focusing on how immune responses vary during dispersal. The cane toad (Rhinella marina) is a well-known invasive species. Populations near the expanding edge of the Australian invasion have altered immune responses compared to toads from longer-established core populations, although this has not been well-documented for Florida populations. In this study, cane toads from a northern edge [New Port Richey (NPR)] and southern core (Miami) population in Florida were collected and injected with lipopolysaccharide (LPS) to compare immune responses. Core population individuals injected with LPS showed greater metabolic increases compared to their baseline rates that were higher compared to those from the edge population. In addition, LPS-injected core individuals had different circulating leukocyte profiles compared to saline-injected cane toads while edge individuals did not. There was a significant interaction between plasma bacteria-killing capability (BKA) and treatment, such that BKA decreased with time in saline compared to LPS-injected individuals, and saline-injected toads from the edge population had lower BKA compared to LPS-injected edge toads at 20 h post-injection. There was also a significant interaction between location and time on circulating corticosterone (CORT) levels following injections with saline or LPS, with CORT decreasing more with time in core population toads. The differential CORT response indicates that differential stress responses contribute to the tradeoffs observed with immunity and dispersal.
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Affiliation(s)
- Steven T Gardner
- Department of Biological Sciences, Auburn University, 331 Funchess Hall, 350 South College St, Auburn, AL, 36849, USA.
| | - Vania R Assis
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua Do Matão, trav. 14, 101, São Paulo, SP, 05508-900, Brazil
| | - Kyra M Smith
- Department of Biological Sciences, Auburn University, 331 Funchess Hall, 350 South College St, Auburn, AL, 36849, USA
| | - Arthur G Appel
- Department of Entomology and Plant Pathology, Auburn University, 301 Funchess Hall, 350 South College St, Auburn, AL, 36849, USA
| | - Mary T Mendonça
- Department of Biological Sciences, Auburn University, 331 Funchess Hall, 350 South College St, Auburn, AL, 36849, USA
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13
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Schoenle LA, Moore IT, Dudek AM, Garcia EB, Mays M, Haussmann MF, Cimini D, Bonier F. Exogenous glucocorticoids amplify the costs of infection by reducing resistance and tolerance, but effects are mitigated by co-infection. Proc Biol Sci 2020; 286:20182913. [PMID: 30966992 DOI: 10.1098/rspb.2018.2913] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Individual variation in parasite defences, such as resistance and tolerance, can underlie heterogeneity in fitness and could influence disease transmission dynamics. Glucocorticoid hormone concentrations often change in response to fluctuating environmental conditions and mediate changes in immune function, resource allocation and tissue repair. Thus, changes in glucocorticoid hormone concentrations might mediate individual variation in investment in resistance versus tolerance. In this study, we experimentally increased glucocorticoid concentrations in red-winged blackbirds ( Agelaius phoeniceus) that were naturally infected with haemosporidian parasites, and assessed changes in resistance and tolerance of infection. Glucocorticoid treatment increased burdens of Plasmodium, the parasite causing avian malaria, but only in the absence of co-infection with another Haemosporidian, Haemoproteus. Thus, glucocorticoids might reduce resistance to infection, but co-infection can mitigate the negative consequences of increased hormone concentrations. Glucocorticoid treatment also decreased tolerance of infection. We found no evidence that the inflammatory immune response or rate of red blood cell production underlie the effects of glucocorticoids on resistance and tolerance. Our findings suggest that exogenous glucocorticoids can increase the costs of haemosporidian infections by both increasing parasite numbers and reducing an individual's ability to cope with infection. These effects could scale up to impact populations of both host and parasite.
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Affiliation(s)
- Laura A Schoenle
- 1 Office of Undergraduate Biology, Cornell University , Ithaca, NY , USA.,2 Department of Biological Sciences, Virginia Tech , Blacksburg, VA , USA
| | - Ignacio T Moore
- 2 Department of Biological Sciences, Virginia Tech , Blacksburg, VA , USA
| | - Alana M Dudek
- 2 Department of Biological Sciences, Virginia Tech , Blacksburg, VA , USA
| | - Ellen B Garcia
- 3 Department of Biological Sciences and Biocomplexity Institute, Virginia Tech , Blacksburg, VA , USA
| | - Morgan Mays
- 2 Department of Biological Sciences, Virginia Tech , Blacksburg, VA , USA
| | - Mark F Haussmann
- 4 Department of Biology, Bucknell University , Lewisburg, PA , USA
| | - Daniela Cimini
- 3 Department of Biological Sciences and Biocomplexity Institute, Virginia Tech , Blacksburg, VA , USA
| | - Frances Bonier
- 2 Department of Biological Sciences, Virginia Tech , Blacksburg, VA , USA.,5 Biology Department, Queen's University , Kingston, Ontario , Canada
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14
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Thomas F, Giraudeau M, Dheilly NM, Gouzerh F, Boutry J, Beckmann C, Biro PA, Hamede R, Abadie J, Labrut S, Bieuville M, Misse D, Bramwell G, Schultz A, Le Loc'h G, Vincze O, Roche B, Renaud F, Russell T, Ujvari B. Rare and unique adaptations to cancer in domesticated species: An untapped resource? Evol Appl 2020. [DOI: 10.1111/eva.12920] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Frédéric Thomas
- CREECUMR IRD 224‐CNRS 5290‐Université de Montpellier Montpellier France
| | - Mathieu Giraudeau
- CREECUMR IRD 224‐CNRS 5290‐Université de Montpellier Montpellier France
| | - Nolwenn M. Dheilly
- School of Marine and Atmospheric Sciences Stony Brook University Stony Brook NY USA
| | - Flora Gouzerh
- CREECUMR IRD 224‐CNRS 5290‐Université de Montpellier Montpellier France
| | - Justine Boutry
- CREECUMR IRD 224‐CNRS 5290‐Université de Montpellier Montpellier France
| | - Christa Beckmann
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Waurn Ponds VIC Australia
- School of Science Western Sydney UniversityParramatta NSW Australia
| | - Peter A. Biro
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Waurn Ponds VIC Australia
| | - Rodrigo Hamede
- School of Natural Sciences University of Tasmania Hobart TAS Australia
| | | | | | - Margaux Bieuville
- CREECUMR IRD 224‐CNRS 5290‐Université de Montpellier Montpellier France
| | - Dorothée Misse
- CREECUMR IRD 224‐CNRS 5290‐Université de Montpellier Montpellier France
| | - Georgina Bramwell
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Waurn Ponds VIC Australia
| | - Aaron Schultz
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Waurn Ponds VIC Australia
| | - Guillaume Le Loc'h
- Clinique des NAC et de la Faune Sauvage, UMR IHAP École Nationale Vétérinaire de Toulouse Toulouse France
| | - Orsolya Vincze
- Hungarian Department of Biology and Ecology Evolutionary Ecology Group Babeş‐Bolyai University Cluj‐Napoca Romania
- Department of Tisza Research MTA Centre for Ecological Research‐DRI Debrecen Hungary
| | - Benjamin Roche
- CREECUMR IRD 224‐CNRS 5290‐Université de Montpellier Montpellier France
- Unité mixte Internationale de Modélisation Mathématique et Informatique des Systèmes Complexes UMI IRD/Sorbonne UniversitéUMMISCO Bondy France
| | - François Renaud
- CREECUMR IRD 224‐CNRS 5290‐Université de Montpellier Montpellier France
| | - Tracey Russell
- School of Life and Environmental Sciences The University of Sydney Sydney NSW Australia
| | - Beata Ujvari
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Waurn Ponds VIC Australia
- School of Natural Sciences University of Tasmania Hobart TAS Australia
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15
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Martínez-Mota R, Kohl KD, Orr TJ, Denise Dearing M. Natural diets promote retention of the native gut microbiota in captive rodents. THE ISME JOURNAL 2020; 14:67-78. [PMID: 31495829 PMCID: PMC6908644 DOI: 10.1038/s41396-019-0497-6] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 08/06/2019] [Accepted: 08/14/2019] [Indexed: 01/18/2023]
Abstract
Wild animals entering captivity experience radical lifestyle changes resulting in microbiome alterations. However, little is known about the factors that drive microbial community shifts in captivity, and what actions could mitigate microbial changes. Using white-throated woodrats (Neotoma albigula), we tested whether offering natural diets in captivity facilitates retention of native microbial communities of captive animals. Wild-caught woodrats were brought to laboratory conditions. Woodrats received either a natural diet of Opuntia cactus or an artificial diet of commercial chow over three weeks. Microbial inventories from woodrat feces at the time of capture and in captivity were generated using Illumina 16S rRNA sequencing. We found that providing woodrats with wild-natural diets significantly mitigated alterations in their microbiota, promoting a 90% retention of native microbial communities across the experiment. In contrast, the artificial diet significantly impacted microbial structure to the extent that 38% of the natural microflora was lost. Core bacteria including Bifidobacterium and Allobaculum were lost, and abundances of microbes related to oxalate degradation decreased in individuals fed artificial but not natural diets. These results highlight the importance of supplementing captive diets with natural foods to maintain native microbiomes of animals kept in artificial conditions for scientific or conservation purposes.
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Affiliation(s)
- Rodolfo Martínez-Mota
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT, 84112, USA
| | - Kevin D Kohl
- Department of Biological Sciences, University of Pittsburgh, 4249 Fifth Avenue, Pittsburgh, PA, 15260, USA
| | - Teri J Orr
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT, 84112, USA
| | - M Denise Dearing
- School of Biological Sciences, University of Utah, 257 South 1400 East, Salt Lake City, UT, 84112, USA.
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16
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Martin LB, Kernbach ME, Unnasch TR. Distinct effects of acute versus chronic corticosterone exposure on Zebra finch responses to West Nile virus. CONSERVATION PHYSIOLOGY 2019; 7:coz094. [PMID: 31824675 PMCID: PMC6894510 DOI: 10.1093/conphys/coz094] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 06/28/2019] [Accepted: 12/03/2019] [Indexed: 06/10/2023]
Abstract
Wild animals are exposed to both short- (acute) and long-term (chronic) stressors. The glucocorticoid hormones, such as corticosterone (CORT), facilitate coping with such stressors, but these hormones can have quite distinct effects contingent on the duration of their elevation. Previously, we found that experimental elevation of CORT for 2 days (via implantation) affected zebra finch (Taeniopygia guttata) responses to West Nile virus (WNV). CORT-elevated birds had higher viremia for at least 2 days longer than controls, and West Nile virus (WNV)-associated mortality occurred only in CORT-elevated birds. Here, we queried how acute elevations of CORT, via injection an hour prior to WNV exposure, would affect host responses, as short-term CORT elevations can be protective in other species. Although CORT injections and implantations elevated circulating CORT to a similar degree, the type of CORT exposure had quite distinct effects on WNV responses. CORT-implanted individuals reached higher viremia and suffered more mortality to WNV than control and CORT-injected individuals. However, CORT-implanted birds maintained body mass better during infection than the other two groups. Our results further support the possibility that chronic physiological stress affects aspects of host competence and potentially community-level WNV disease dynamics.
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Affiliation(s)
- Lynn B Martin
- Global Health and Infectious Disease Research Center, University of South Florida, Tampa, FL 33620, USA
| | - Meredith E Kernbach
- Global Health and Infectious Disease Research Center, University of South Florida, Tampa, FL 33620, USA
| | - Thomas R Unnasch
- Global Health and Infectious Disease Research Center, University of South Florida, Tampa, FL 33620, USA
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17
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Matsushima W, Brink K, Schroeder J, Miska EA, Gapp K. Mature sperm small-RNA profile in the sparrow: implications for transgenerational effects of age on fitness. ENVIRONMENTAL EPIGENETICS 2019; 5:dvz007. [PMID: 31139435 PMCID: PMC6527922 DOI: 10.1093/eep/dvz007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 03/16/2019] [Accepted: 04/09/2019] [Indexed: 05/13/2023]
Abstract
Mammalian sperm RNA has recently received a lot of interest due to its involvement in epigenetic germline inheritance. Studies of epigenetic germline inheritance have shown that environmental exposures can induce effects in the offspring without altering the DNA sequence of germ cells. Most mechanistic studies were conducted in laboratory rodents and C.elegans while observational studies confirm the phenotypic phenomenon in wild populations of humans and other species including birds. Prominently, paternal age in house sparrows affects offspring fitness, yet the mechanism is unknown. This study provides a first reference of house sparrow sperm small RNA as an attempt to uncover their role in the transmission of the effects of paternal age on the offspring. In this small-scale pilot, we found no statistically significant differences between miRNA and tRNA fragments in aged and prime sparrow sperm. These results indicate a role of other epigenetic information carriers, such as distinct RNA classes, RNA modifications, DNA methylation and retained histones, and a clear necessity of future studies in wild populations.
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Affiliation(s)
- Wayo Matsushima
- Wellcome Trust/Cancer Research UK Gurdon Institute, Henry Wellcome Building of Cancer and Developmental Biology, Tennis Court Road, Cambridge CB2 1QN, UK
- Wellcome Sanger Institute, Human Genetics Programme, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, UK
- Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
| | - Kristiana Brink
- Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot SL5 7PY, UK
| | - Julia Schroeder
- Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot SL5 7PY, UK
| | - Eric A Miska
- Wellcome Trust/Cancer Research UK Gurdon Institute, Henry Wellcome Building of Cancer and Developmental Biology, Tennis Court Road, Cambridge CB2 1QN, UK
- Wellcome Sanger Institute, Human Genetics Programme, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, UK
- Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
| | - Katharina Gapp
- Wellcome Trust/Cancer Research UK Gurdon Institute, Henry Wellcome Building of Cancer and Developmental Biology, Tennis Court Road, Cambridge CB2 1QN, UK
- Wellcome Sanger Institute, Human Genetics Programme, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, UK
- Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
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18
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Fischer CP, Romero LM. Chronic captivity stress in wild animals is highly species-specific. CONSERVATION PHYSIOLOGY 2019; 7:coz093. [PMID: 31824674 PMCID: PMC6892464 DOI: 10.1093/conphys/coz093] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 10/04/2019] [Accepted: 10/13/2019] [Indexed: 05/05/2023]
Abstract
Wild animals are brought into captivity for many reasons-conservation, research, agriculture and the exotic pet trade. While the physical needs of animals are met in captivity, the conditions of confinement and exposure to humans can result in physiological stress. The stress response consists of the suite of hormonal and physiological reactions to help an animal survive potentially harmful stimuli. The adrenomedullary response results in increased heart rate and muscle tone (among other effects); elevated glucocorticoid (GC) hormones help to direct resources towards immediate survival. While these responses are adaptive, overexposure to stress can cause physiological problems, such as weight loss, changes to the immune system and decreased reproductive capacity. Many people who work with wild animals in captivity assume that they will eventually adjust to their new circumstances. However, captivity may have long-term or permanent impacts on physiology if the stress response is chronically activated. We reviewed the literature on the effects of introduction to captivity in wild-caught individuals on the physiological systems impacted by stress, particularly weight changes, GC regulation, adrenomedullary regulation and the immune and reproductive systems. This paper did not review studies on captive-born animals. Adjustment to captivity has been reported for some physiological systems in some species. However, for many species, permanent alterations to physiology may occur with captivity. For example, captive animals may have elevated GCs and/or reduced reproductive capacity compared to free-living animals even after months in captivity. Full adjustment to captivity may occur only in some species, and may be dependent on time of year or other variables. We discuss some of the methods that can be used to reduce chronic captivity stress.
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Affiliation(s)
| | - L Michael Romero
- Department of Biology, 200 College Ave. Tufts University, Medford, MA 02155 USA
- Corresponding author: Department of Biology, Medford, MA 02155, USA.
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19
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Andrew SC, Jensen H, Hagen IJ, Lundregan S, Griffith SC. Signatures of genetic adaptation to extremely varied Australian environments in introduced European house sparrows. Mol Ecol 2018; 27:4542-4555. [DOI: 10.1111/mec.14897] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 09/24/2018] [Indexed: 12/19/2022]
Affiliation(s)
- Samuel C. Andrew
- Department of Biological Sciences; Macquarie University; Sydney New South Wales Australia
| | - Henrik Jensen
- Centre for Biodiversity Dynamics; Department of Biology; Norwegian University of Science and Technology; Trondheim Norway
| | - Ingerid J. Hagen
- Centre for Biodiversity Dynamics; Department of Biology; Norwegian University of Science and Technology; Trondheim Norway
- Norwegian Institute for Nature Research; Trondheim Norway
| | - Sarah Lundregan
- Centre for Biodiversity Dynamics; Department of Biology; Norwegian University of Science and Technology; Trondheim Norway
| | - Simon C. Griffith
- Department of Biological Sciences; Macquarie University; Sydney New South Wales Australia
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20
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Cuervo PF, Beldomenico PM, Sánchez A, Pietrobon E, Valdez SR, Racca AL. Chronic exposure to environmental stressors enhances production of natural and specific antibodies in rats. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2018; 329:536-546. [DOI: 10.1002/jez.2218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 06/14/2018] [Accepted: 07/04/2018] [Indexed: 01/13/2023]
Affiliation(s)
- Pablo Fernando Cuervo
- Laboratorio de Ecología de Enfermedades, Instituto de Ciencias Veterinarias del Litoral, Universidad Nacional del Litoral/Consejo Nacional de Investigaciones Científicas y Técnicas; Esperanza Argentina
| | - Pablo Martín Beldomenico
- Laboratorio de Ecología de Enfermedades, Instituto de Ciencias Veterinarias del Litoral, Universidad Nacional del Litoral/Consejo Nacional de Investigaciones Científicas y Técnicas; Esperanza Argentina
- Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral; Esperanza Argentina
| | - Amorina Sánchez
- Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral; Esperanza Argentina
| | - Elisa Pietrobon
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo, Consejo Nacional de Investigaciones Científicas y Técnicas; Mendoza Argentina
| | - Susana Ruth Valdez
- Laboratorio de Reproducción y Lactancia, Instituto de Medicina y Biología Experimental de Cuyo, Consejo Nacional de Investigaciones Científicas y Técnicas; Mendoza Argentina
| | - Andrea Laura Racca
- Laboratorio de Ecología de Enfermedades, Instituto de Ciencias Veterinarias del Litoral, Universidad Nacional del Litoral/Consejo Nacional de Investigaciones Científicas y Técnicas; Esperanza Argentina
- Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral; Esperanza Argentina
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21
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Brown GP, Holden D, Shine R, Phillips BL. Invasion history alters the behavioural consequences of immune system activation in cane toads. J Anim Ecol 2018; 87:716-726. [DOI: 10.1111/1365-2656.12799] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 12/22/2017] [Indexed: 02/02/2023]
Affiliation(s)
- Gregory P. Brown
- School of Life and Environmental Sciences University of Sydney Sydney NSW Australia
| | - Damian Holden
- School of Life and Environmental Sciences University of Sydney Sydney NSW Australia
| | - Richard Shine
- School of Life and Environmental Sciences University of Sydney Sydney NSW Australia
| | - Ben L. Phillips
- School of Biosciences University of Melbourne Parkville Vic. Australia
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22
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Habig B, Doellman MM, Woods K, Olansen J, Archie EA. Social status and parasitism in male and female vertebrates: a meta-analysis. Sci Rep 2018; 8:3629. [PMID: 29483573 PMCID: PMC5827031 DOI: 10.1038/s41598-018-21994-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 02/14/2018] [Indexed: 12/21/2022] Open
Abstract
Social status is an important predictor of parasite risk in vertebrates. To date, general frameworks to explain status-related variation in parasitism have remained elusive. In this meta-analysis, we evaluated five hypotheses proposed to explain status-related variation in parasitism in male and female vertebrates by leveraging variation in hierarchy type, mating system, parasite transmission mode, and allostatic load to test associated predictions. Our meta-analyses span 66 analyses (26 studies) of male vertebrates (two orders and five classes), and 62 analyses (13 studies) of female vertebrates (four vertebrate orders). Contrary to the prevailing paradigm that low status is linked to poor health, we found that dominant animals typically faced higher parasite risk than subordinates. This pattern was especially well-supported in analyses of males versus females, in linear versus egalitarian hierarchies, in mating systems where dominance rank predicts mating effort, and for contact- and environmentally-transmitted parasites rather than vector-borne parasites. These findings supported the priority-of-access and tradeoffs hypotheses suggesting that variation in parasitism is driven by rank-associated differences in exposure to parasites and mating effort. Together, these results suggest that high parasite risk might sometimes be an unappreciated cost of high rank, and conversely, reduced parasite risk might be a benefit of social subordination.
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Affiliation(s)
- Bobby Habig
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, IN, 46556, USA.
| | - Meredith M Doellman
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, IN, 46556, USA
| | - Kourtney Woods
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, IN, 46556, USA
| | - Jonathan Olansen
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, IN, 46556, USA
| | - Elizabeth A Archie
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, IN, 46556, USA
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23
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Gervasi SS, Burkett-Cadena N, Burgan SC, Schrey AW, Hassan HK, Unnasch TR, Martin LB. Host stress hormones alter vector feeding preferences, success, and productivity. Proc Biol Sci 2017; 283:rspb.2016.1278. [PMID: 27512147 DOI: 10.1098/rspb.2016.1278] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 07/15/2016] [Indexed: 01/05/2023] Open
Abstract
Stress hormones might represent a key link between individual-level infection outcome, population-level parasite transmission, and zoonotic disease risk. Although the effects of stress on immunity are well known, stress hormones could also affect host-vector interactions via modification of host behaviours or vector-feeding patterns and subsequent reproductive success. Here, we experimentally manipulated songbird stress hormones and examined subsequent feeding preferences, feeding success, and productivity of mosquito vectors in addition to defensive behaviours of hosts. Despite being more defensive, birds with elevated stress hormone concentrations were approximately twice as likely to be fed on by mosquitoes compared to control birds. Moreover, stress hormones altered the relationship between the timing of laying and clutch size in blood-fed mosquitoes. Our results suggest that host stress could affect the transmission dynamics of vector-borne parasites via multiple pathways.
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Affiliation(s)
- Stephanie S Gervasi
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620, USA
| | - Nathan Burkett-Cadena
- Florida Medical Entomology Laboratory, University of Florida, Vero Beach, FL 32962, USA
| | - Sarah C Burgan
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620, USA
| | - Aaron W Schrey
- Biology Department, Armstrong State University, Savannah, GA 31419, USA
| | - Hassan K Hassan
- Department of Global Health, University of South Florida, Tampa, FL 33620, USA
| | - Thomas R Unnasch
- Department of Global Health, University of South Florida, Tampa, FL 33620, USA
| | - Lynn B Martin
- Department of Integrative Biology, University of South Florida, Tampa, FL 33620, USA
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24
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Huber N, Fusani L, Ferretti A, Mahr K, Canoine V. Measuring short-term stress in birds: Comparing different endpoints of the endocrine-immune interface. Physiol Behav 2017; 182:46-53. [DOI: 10.1016/j.physbeh.2017.09.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 09/11/2017] [Accepted: 09/18/2017] [Indexed: 01/10/2023]
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25
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Schoenle LA, Kernbach M, Haussmann MF, Bonier F, Moore IT. An experimental test of the physiological consequences of avian malaria infection. J Anim Ecol 2017; 86:1483-1496. [DOI: 10.1111/1365-2656.12753] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 08/24/2017] [Indexed: 01/03/2023]
Affiliation(s)
| | - Meredith Kernbach
- Department of Biological Sciences Virginia Tech Blacksburg VA USA
- Department of Integrative Biology University of South Florida Tampa FL USA
| | | | - Frances Bonier
- Department of Biological Sciences Virginia Tech Blacksburg VA USA
- Biology Department Queen's University Kingston ON Canada
| | - Ignacio T. Moore
- Department of Biological Sciences Virginia Tech Blacksburg VA USA
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26
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Love AC, Lovern MB, DuRant SE. Captivity influences immune responses, stress endocrinology, and organ size in house sparrows (Passer domesticus). Gen Comp Endocrinol 2017; 252:18-26. [PMID: 28733227 DOI: 10.1016/j.ygcen.2017.07.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 07/08/2017] [Accepted: 07/16/2017] [Indexed: 01/01/2023]
Abstract
Studies using wild animals in laboratory-based research require bringing wild-captured organisms into a novel setting, which can have long-lasting impacts on physiology and behavior. In several species, captivity stimulates stress hormone production and can alter immune function. Despite this, there is little consensus on how captivity influences stress hormone regulation, or if captivity-induced changes in stress hormone production and regulation mediate changes in immune function. In this study, we investigate the influence of captivity on the physiology of a wild bird commonly-used in laboratory-based research, the house sparrow (Passer domesticus). We tested how captivity influences stress endocrinology, immune responses, and organ mass, and also investigated if the production or regulation of corticosterone, the main stress hormone in birds, correlated with changes in immunity. We found that baseline corticosterone concentrations and maximum capacity of the adrenals to secrete corticosterone increase following captivity and remain elevated after 9weeks of captivity. A measure of innate immune function, the bactericidal ability of plasma, also increased with time spent in captivity. Wound healing was also influenced by time spent in captivity, with birds taking almost 2days longer to heal if they were wounded after 3weeks in captivity when compared with birds that were wounded immediately upon capture. Additionally, captivity caused notable reductions in spleen and liver mass. Together, these results imply that captivity can have long-lasting effects on house sparrow corticosterone release and immune function, and suggest that even after 9weeks house sparrows do not acclimate physiologically to life in captivity.
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Affiliation(s)
- Ashley C Love
- Department of Integrative Biology, Oklahoma State University, Stillwater, OK 74078, USA.
| | - Matthew B Lovern
- Department of Integrative Biology, Oklahoma State University, Stillwater, OK 74078, USA
| | - Sarah E DuRant
- Department of Integrative Biology, Oklahoma State University, Stillwater, OK 74078, USA
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27
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Wein Y, Geva Z, Bar-Shira E, Friedman A. Transport-related stress and its resolution in turkey pullets: activation of a pro-inflammatory response in peripheral blood leukocytes. Poult Sci 2017; 96:2601-2613. [DOI: 10.3382/ps/pex076] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 03/15/2017] [Indexed: 12/21/2022] Open
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28
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Silva DMMD, Pinheiro L, Azevedo CS, Costa GDP, Talvani A. Influence of environmental enrichment on the behavior and physiology of mice infected by Trypanosoma cruzi. Rev Soc Bras Med Trop 2017; 50:341-349. [DOI: 10.1590/0037-8682-0536-2016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 05/18/2017] [Indexed: 11/22/2022] Open
Affiliation(s)
| | | | | | | | - André Talvani
- Universidade Federal de Ouro Preto, Brazil; Universidade Federal de Ouro Preto, Brazil; Universidade Federal de Ouro Preto, Brazil; Universidade Federal de Ouro Preto, Brazil
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29
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Lattin CR, Pechenenko AV, Carson RE. Experimentally reducing corticosterone mitigates rapid captivity effects on behavior, but not body composition, in a wild bird. Horm Behav 2017; 89:121-129. [PMID: 28065712 PMCID: PMC5359069 DOI: 10.1016/j.yhbeh.2016.12.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 12/23/2016] [Accepted: 12/29/2016] [Indexed: 01/02/2023]
Abstract
Wild animals and captives display physiological and behavioral differences, and it has been hypothesized, but rarely tested, that these differences are caused by sustained elevation of the hormone corticosterone. We used repeated computed tomography (CT) imaging to examine body composition changes in breeding male and female wild house sparrows (Passer domesticus; n=20) in response to two weeks of captivity, and assessed behavioral changes using video recordings. Half of the birds received the drug mitotane, which significantly decreased stress-induced corticosterone titers compared to controls. Based on the CT images, fat volumes increased, and pectoralis muscle density and heart and testes volumes decreased, over the two weeks of captivity in both groups of birds. However, beak-wiping, a behavior that can indicate anxiety and aggression, showed increased occurrence in controls compared to mitotane-treated birds. While our results do not support the hypothesis that these body composition changes were primarily driven by stress-induced corticosterone, our data suggest that experimentally reducing stress-induced corticosterone may mitigate some captivity-induced behavioral changes. Broadly, our results emphasize that researchers should take behavioral and physiological differences between free-living animals and captives into consideration when designing studies and interpreting results. Further, time in captivity should be minimized when birds will be reintroduced back to the wild.
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Affiliation(s)
- Christine R Lattin
- Department of Radiology and Biomedical Imaging, Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT 06520-8048, United States.
| | - Anita V Pechenenko
- Department of Radiology and Biomedical Imaging, Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT 06520-8048, United States
| | - Richard E Carson
- Department of Radiology and Biomedical Imaging, Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT 06520-8048, United States
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30
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Martin LB, Kilvitis HJ, Brace AJ, Cooper L, Haussmann MF, Mutati A, Fasanello V, O'Brien S, Ardia DR. Costs of immunity and their role in the range expansion of the house sparrow in Kenya. J Exp Biol 2017; 220:2228-2235. [DOI: 10.1242/jeb.154716] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 04/02/2017] [Indexed: 01/09/2023]
Abstract
There are at least two reasons to study traits that mediate successful range expansions. First, dispersers will found new populations and thus impact the distribution and evolution of species. Second, organisms moving into new areas will influence the fate of resident communities, directly competing with or indirectly affecting residents by spreading non-native or spilling-back native parasites. The success of invaders in new areas is likely mediated by a counterbalancing of costly traits. In new areas where threats are comparatively rare, individuals that grow rapidly and breed prolifically should be at an advantage. High investment in defenses should thus be disfavored. In the present study, we compared the energetic, nutritional and collateral damage costs of an inflammatory response among Kenyan house sparrow (Passer domesticus) populations of different ages, asking whether costs were related to traits of individuals from three different capture sites. Kenya is among the world's most recent range expansions for this species, and we recently found that the expression of Toll-like receptors (TLRs), leukocyte receptors that instigate inflammatory responses when bound to microbial elements, was related to the range expansion across the country. Here, we found (contrary to our expectations) that energetic and nutritional costs of inflammation were higher, but damage costs were lower, in range-edge compared to core birds. Moreover, at the individual level, TLR-4 expression was negatively related to commodity costs (energy and a critical amino acid) of inflammation. Our data thus suggest that costs of inflammation, perhaps mediated by TLR expression, might mitigate successful range expansions.
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Affiliation(s)
- Lynn B. Martin
- University of South Florida, Department of Integrative Biology, Tampa FL 33620, USA
| | - Holly J. Kilvitis
- University of South Florida, Department of Integrative Biology, Tampa FL 33620, USA
| | - Amber J. Brace
- University of South Florida, Department of Integrative Biology, Tampa FL 33620, USA
| | - Laken Cooper
- Radford University, Department of Biology, Radford, VA 24142, USA
| | | | - Alex Mutati
- National Museums of Kenya, Department of Ornithology, Nairobi, Kenya
| | - Vincent Fasanello
- Bucknell University, Department of Biology, Lewisburg, PA, USA
- Washington University in Saint Louis, Department of Biology, Saint Louis, MO, USA
| | - Sara O'Brien
- Radford University, Department of Biology, Radford, VA 24142, USA
| | - Daniel R. Ardia
- Franklin and Marshall College, Department of Biology, Lancaster, PA, USA
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Broughton DR, Schneider BC, McGraw KJ, Ardia DR. Carotenoids buffer the acute phase response on fever, sickness behavior, and rapid bill color change in zebra finches. J Exp Biol 2017; 220:2957-2964. [DOI: 10.1242/jeb.155069] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Accepted: 06/01/2017] [Indexed: 12/18/2022]
Abstract
Carotenoids are finite resources that animals can allocate to self-maintenance, attractiveness, or reproduction. Here we test how carotenoids affect the acute phase response (APR), an intense rapid systemic response characterized by fever, sickness behavior, and production of acute phase proteins, which serves to reduce pathogen persistence. We conducted a 2x2 factorial design experiment in captive adult male and female zebra finches (Taeniopygia guttata) to determine the effects of carotenoid supplementation on the intensity of the APR. We measured changes in feeding rate, activity level, and body temperature of the birds. We found that, relative to unsupplemented controls, carotenoid-supplemented birds exhibited less severe reductions in feeding and activity, smaller increases in body temperature, and lower circulating levels of haptoglobin (an acute phase protein) 24 h after inducing an APR. Among supplemented individuals, those with higher blood carotenoid levels exhibited a lower reduction in activity rate after 24 h. Forty-eight hours after APR induction, birds exhibited a significant decrease in plasma carotenoid levels and a decrease in bill hue, with less reduction in hue in carotenoid-supplemented individuals. These results demonstrate that carotenoids can alleviate several important behavioral and physiological effects of an APR and that bill color can change rapidly following induction of the costly APR immune defense. In particular, immune activation may have caused birds to preferentially draw down carotenoids from the bloodstream, ostensibly for use in health. Rapid bill color changes over a 48-hr period support growing evidence that bills may serve as short-term signals of health and condition.
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Affiliation(s)
- Deanna R. Broughton
- Department of Biology, Franklin & Marshall College, Lancaster, PA 17604, USA
| | - Brent C. Schneider
- Department of Biology, Franklin & Marshall College, Lancaster, PA 17604, USA
| | - Kevin J. McGraw
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Daniel R. Ardia
- Department of Biology, Franklin & Marshall College, Lancaster, PA 17604, USA
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Bailly J, Garnier S, Khimoun A, Arnoux E, Eraud C, Goret J, Luglia T, Gaucher P, Faivre B. Reduced inflammation in expanding populations of a neotropical bird species. Ecol Evol 2016; 6:7511-7521. [PMID: 28725417 PMCID: PMC5513268 DOI: 10.1002/ece3.2486] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 08/12/2016] [Accepted: 08/18/2016] [Indexed: 01/29/2023] Open
Abstract
The loss of regulating agents such as parasites is among the most important changes in biotic interactions experienced by populations established in newly colonized areas. Under a relaxed parasite pressure, individuals investing less in costly immune mechanisms might experience a selective advantage and become successful colonizers as they re‐allocate resources to other fitness‐related traits. Accordingly, a refinement of the evolution of increased competitive ability (EICA) hypothesis proposed that immunity of invasive populations has evolved toward a reduced investment in innate immunity, the most costly component of immunity, and an increased humoral immunity that is less costly. Biogeographical approaches comparing populations between native and expansion ranges are particularly relevant in exploring this issue, but remain very scarce. We conducted a biogeographical comparison between populations of Spectacled Thrush (Turdus nudigenis) from the native area (South America) and from the expansion range (Caribbean islands). First, we compared haemosporidian prevalence and circulating haptoglobin (an acute‐phase protein produced during inflammation). Second, we challenged captive birds from both ranges with Escherichia coli lipopolysaccharides (LPS) and measured postchallenge haptoglobin production and body mass change. Birds from the expansion range showed lower haemosporidian prevalence and lower levels of haptoglobin than birds from the native range. In addition, the inflammation elicited by LPS injection and its associated cost in terms of body mass loss were lower in birds from the expansion range than in birds from the native range. In accordance with the enemy release hypothesis, our results suggest that range expansion is associated with a reduced infection risk. Our study also supports the hypothesis that individuals from newly established populations have evolved mechanisms to dampen the inflammatory response and are in accordance with one prediction of the refined EICA hypothesis, proposed to understand biological invasions.
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Affiliation(s)
- Juliette Bailly
- BioGéoSciencesUMR CNRS 6282Univ Bourgogne Franche‐ComtéDijonFrance
| | - Stéphane Garnier
- BioGéoSciencesUMR CNRS 6282Univ Bourgogne Franche‐ComtéDijonFrance
| | - Aurélie Khimoun
- BioGéoSciencesUMR CNRS 6282Univ Bourgogne Franche‐ComtéDijonFrance
| | - Emilie Arnoux
- BioGéoSciencesUMR CNRS 6282Univ Bourgogne Franche‐ComtéDijonFrance
| | - Cyril Eraud
- Office National de la Chasse et de la Faune SauvageCNERA Avifaune migratriceVilliers en BoisFrance
| | - Jean‐Yves Goret
- UMR Ecologie des Forêts de GuyaneKourou CedexGuyane FrançaiseFrance
| | - Thomas Luglia
- Groupe d'Etude et de Protection des Oiseaux de GuyaneCayenneGuyane FrançaiseFrance
| | | | - Bruno Faivre
- BioGéoSciencesUMR CNRS 6282Univ Bourgogne Franche‐ComtéDijonFrance
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DuRant SE, Arciniega ML, Bauer CM, Romero LM. A test of reactive scope: Reducing reactive scope causes delayed wound healing. Gen Comp Endocrinol 2016; 236:115-120. [PMID: 27432814 DOI: 10.1016/j.ygcen.2016.07.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 07/14/2016] [Indexed: 12/18/2022]
Abstract
Reactive scope predicts that all animals have an adaptive ability to respond to stressors in their environment, termed reactive homeostasis, and that only when an animal's response to stressful stimuli exceeds a certain threshold (homeostatic overload) will stress have pathological effects. While this framework has successfully helped interpret effects of stressors on wildlife, no study has designed an experiment to directly test this framework. This study was designed to expose house sparrows (Passer domesticus) to treatments that would result in varying ranges of reactive homeostasis during chronic stress, which based on the reactive scope model should cause birds with the lowest reactive homeostasis range to exhibit signs of pathology during a subsequent challenge. To modulate the reactive homeostasis range, we altered allostatic load of birds by exposing them to chronic stress while either elevating, blocking, or not manipulating corticosterone. After concluding chronic stress treatments, birds were exposed to the subsequent challenge of a superficial wound. Individuals treated with corticosterone during chronic stress (high allostatic load) experienced the most pathology, including both weight loss and slower wound healing. Unmanipulated birds (medium allostatic load) also experienced weight loss but had normal healing rates, while birds with blocked corticosterone (low allostatic load) had minimal weight loss and normal healing rates. Our results indicate that increased allostatic load reduces the reactive homeostasis range, thereby causing individuals to cross the homeostatic overload threshold sooner, and thus support the reactive scope framework.
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Affiliation(s)
- S E DuRant
- Department of Integrative Biology, Oklahoma State University, Stillwater OK, 74078, United States; Department of Biology, Tufts University, Medford, MA 02144, United States.
| | - M L Arciniega
- Department of Biology, Tufts University, Medford, MA 02144, United States
| | - C M Bauer
- Department of Biology, Tufts University, Medford, MA 02144, United States
| | - L M Romero
- Department of Biology, Tufts University, Medford, MA 02144, United States
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Stutz WE, Schmerer M, Coates JL, Bolnick DI. Among-lake reciprocal transplants induce convergent expression of immune genes in threespine stickleback. Mol Ecol 2015; 24:4629-46. [PMID: 26118468 DOI: 10.1111/mec.13295] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Revised: 06/22/2015] [Accepted: 06/24/2015] [Indexed: 12/25/2022]
Abstract
Geographic variation in parasite communities can drive evolutionary divergence in host immune genes. However, biotic and abiotic environmental variation can also induce plastic differences in immune function among populations. At present, there is little information concerning the relative magnitudes of heritable vs. induced immune divergence in natural populations. We examined immune gene expression profiles of threespine stickleback (Gasterosteus aculeatus) from six lakes on Vancouver Island, British Columbia. Parasite community composition differs between lake types (large or small, containing limnetic- or benthic-like stickleback) and between watersheds. We observed corresponding differences in immune gene expression profiles among wild-caught stickleback, using a set of seven immune genes representing distinct branches of the immune system. To evaluate the role of environmental effects on this differentiation, we experimentally transplanted wild-caught fish into cages in their native lake, or into a nearby foreign lake. Transplanted individuals' immune gene expression converged on patterns typical of their destination lake, deviating from their native expression profile. Transplant individuals' source population had a much smaller effect, suggesting relatively weak genetic underpinning of population differences in immunity, as viewed through gene expression. This strong environmental regulation of immune gene expression provides a counterpoint to the large emerging literature documenting microevolution and genetic diversification of immune function. Our findings illustrate the value of studying immunity in natural environmental settings where the immune system has evolved and actively functions.
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Affiliation(s)
- William E Stutz
- Department of Integrative Biology, University of Texas at Austin, One University Station C0990, Austin, TX, 78712, USA
| | - Matthew Schmerer
- Department of Integrative Biology, University of Texas at Austin, One University Station C0990, Austin, TX, 78712, USA
| | - Jessica L Coates
- Department of Biology, Spelman College, 350 Spelman Lane SW, Atlanta, GA, 30314, USA
| | - Daniel I Bolnick
- Department of Integrative Biology, University of Texas at Austin, One University Station C0990, Austin, TX, 78712, USA.,Howard Hughes Medical Institute, University of Texas at Austin, One University Station C0990, Austin, TX, 78712, USA
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Schulte-Hostedde AI, Mastromonaco GF. Integrating evolution in the management of captive zoo populations. Evol Appl 2015; 8:413-22. [PMID: 26029256 PMCID: PMC4430766 DOI: 10.1111/eva.12258] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Accepted: 02/27/2015] [Indexed: 01/12/2023] Open
Abstract
Both natural animal populations and those in captivity are subject to evolutionary forces. Evolutionary changes to captive populations may be an important, but poorly understood, factor that can affect the sustainability of these populations. The importance of maintaining the evolutionary integrity of zoo populations, especially those that are used for conservation efforts including reintroductions, is critical for the conservation of biodiversity. Here, we propose that a greater appreciation for an evolutionary perspective may offer important insights that can enhance the reproductive success and health for the sustainability of captive populations. We provide four examples and associated strategies that highlight this approach, including minimizing domestication (i.e., genetic adaptation to captivity), integrating natural mating systems into captive breeding protocols, minimizing the effects of translocation on variation in photoperiodism, and understanding the interplay of parasites/pathogens and inflammation. There are a myriad of other issues that may be important for captive populations, and we conclude that these may often be species specific. Nonetheless, an evolutionary perspective may mitigate some of the challenges currently facing captive populations that are important from a conservation perspective, including their sustainability.
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Habig B, Archie EA. Social status, immune response and parasitism in males: a meta-analysis. Philos Trans R Soc Lond B Biol Sci 2015; 370:20140109. [PMID: 25870395 PMCID: PMC4410375 DOI: 10.1098/rstb.2014.0109] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2015] [Indexed: 12/15/2022] Open
Abstract
In male vertebrates, two conflicting paradigms--the energetic costs of high dominance rank and the chronic stress of low rank--have been proposed to explain patterns of immune function and parasitism. To date, neither paradigm has provided a complete explanation for status-related differences in male health. Here, we applied meta-analyses to test for correlations between male social status, immune responses and parasitism. We used an ecoimmunological framework, which proposes that males should re-allocate investment in different immune components depending on the costs of dominance or subordination. Spanning 297 analyses, from 77 studies on several vertebrate taxa, we found that most immune responses were similar between subordinate and dominant males, and neither dominant nor subordinate males consistently invested in predictable immune components. However, subordinate males displayed significantly lower delayed-type hypersensitivity and higher levels of some inflammatory cytokines than dominant males, while dominant males exhibited relatively lower immunoglobulin responses than subordinate males. Despite few differences in immunity, dominant males exhibited consistently higher parasitism than subordinate males, including protozoan blood parasites, ectoparasites and gastrointestinal helminths. We discuss our results in the context of the costs of dominance and subordination and advocate future work that measures both parasitism and immune responses in wild systems.
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Affiliation(s)
- Bobby Habig
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, IN 46556, USA
| | - Elizabeth A Archie
- Department of Biological Sciences, University of Notre Dame, 100 Galvin Life Sciences Center, Notre Dame, IN 46556, USA
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Martin LB, Liebl AL, Kilvitis HJ. Covariation in stress and immune gene expression in a range expanding bird. Gen Comp Endocrinol 2015; 211:14-9. [PMID: 25448257 DOI: 10.1016/j.ygcen.2014.11.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Revised: 10/21/2014] [Accepted: 11/02/2014] [Indexed: 11/23/2022]
Abstract
The enemy release hypothesis (ERH) posits that hosts encounter fewer infectious parasites when they arrive in new areas, so individuals that adjust their immune defenses most effectively should thrive and even expand the range of that species. An important aspect of vertebrate immune defense is inflammation, as it provides rapid defense against diverse parasites. Glucocorticoids (GCs) are integral to the regulation of inflammation, so here we investigated whether and how covariation in the expression of genes affecting the regulation of inflammation and GCs might have impacted the house sparrow (Passer domesticus) invasion of Kenya. Toll-like receptors 2 and 4 (TLRs) detect microbial threats and instigate inflammatory responses, whereas the glucocorticoid receptor (GR) is integral to resolving inflammation via both local and systemic pathways. As with a previous study on circulating leukocytes, we found that splenic TLR-4 and TLR-2 (the latter marginally non-significant) expression was higher in younger than older populations but only when differences in spleen size were considered; birds at the range edge had larger spleens. In regards to covariation, we found that TLR-2, TLR-4 and GR expression were closely inter-related within individuals, but covariation did not differ among populations. Subsequently, our data suggest that house sparrows are using variants of a common stress-immune regulatory mechanism to expand their Kenyan range.
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Affiliation(s)
- Lynn B Martin
- University of South Florida, Department of Integrative Biology, SCA 110, Tampa, FL 33620, United States.
| | - Andrea L Liebl
- Centre for Ecology and Conservation, University of Exeter, Cornwall, Penryn TR10 9EZ, UK
| | - Holly J Kilvitis
- University of South Florida, Department of Integrative Biology, SCA 110, Tampa, FL 33620, United States
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Martin LB, Liebl AL. Physiological flexibility in an avian range expansion. Gen Comp Endocrinol 2014; 206:227-34. [PMID: 25125084 DOI: 10.1016/j.ygcen.2014.07.016] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 06/13/2014] [Accepted: 07/20/2014] [Indexed: 11/29/2022]
Abstract
The mechanisms that enable animals to colonize new areas are little known, but growing evidence indicates that the regulation of stress hormones is important. Stress hormones probably influence invasions because they enable organisms to adjust their phenotypes depending on environmental context. Often, studies of stress hormones are based on single or a few samples from individuals even though the flexibility in the regulation of such hormones is what enables them to achieve homeostasis and facilitate performance. Here, we asked whether flexibility in the regulation of one stress hormone, corticosterone, was related to colonization success in one of the world's most successful avian invaders, the house sparrow (Passer domesticus). We studied Kenyan house sparrows, as the species was recently introduced there (around 1950) and has since expanded northwestward. Previous work in this system revealed that younger populations released more corticosterone during a restraint stressor than older populations. Our first goal was to discern whether such population differences were fixed or flexible in adulthood; our second goal was to determine whether individual identity explained any variation in corticosterone regulation. As before, we found that corticosterone responses to short-term restraint (i.e., stress responses), but not baseline corticosterone, were larger in younger populations. We also found that both baseline and stress-induced corticosterone measures were flexible; both metrics became similar among sites after one week of captivity. For stress responses, we also found that individual identity was important. Altogether, the present data suggest that the colonization of Kenya by house sparrows might have been facilitated by stress hormone regulatory flexibility.
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Affiliation(s)
- Lynn B Martin
- University of South Florida, Department of Integrative Biology, SCA 110, Tampa, FL 33620, United States.
| | - Andrea L Liebl
- University of South Florida, Department of Integrative Biology, SCA 110, Tampa, FL 33620, United States; University of Exeter, Centre for Ecology and Conservation, Penryn TR10 9EZ, United Kingdom
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Sild E, Meitern R, Männiste M, Karu U, Hõrak P. High feather corticosterone indicates better coccidian infection resistance in greenfinches. Gen Comp Endocrinol 2014; 204:203-10. [PMID: 24953456 DOI: 10.1016/j.ygcen.2014.05.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Revised: 04/21/2014] [Accepted: 05/19/2014] [Indexed: 11/22/2022]
Abstract
Differential exposure or sensitivity to stressors can have substantial effects on the variation in immune responsiveness of animals. However, the questions about the causes and consequences of these processes have remained largely unclear, particularly as regards wild animals and their natural pathogens. Here we ask how a potential marker of stress responses, the feather corticosterone (CORT) content, reflects the resistance to an experimental infection with natural coccidian parasites in wild-caught captive greenfinches (Carduelis chloris). CORT content of tail feathers grown in captivity correlated positively with a behavioural measure of captivity-intolerance, i.e., the amount of damage accrued to tail feathers in captivity that results from flapping against cage bars. This finding is consistent with an idea that feather CORT reflects the amount of stress experienced during feather growth. Experimental infection with heterologous coccidian strains increased feather CORT levels. Birds with highest feather CORT levels appeared most resistant to new infection, assessed on the basis of parasite oocyst shedding at the peak phase of infection. Birds with highest feather CORT levels also cleared the infection faster than the birds with lower feather CORT levels. These findings provide the first evidence about positive covariation between feather CORT and resistance to a natural pathogen in a wild bird species. Assuming that feather CORT levels reflect circulating hormone titres, these findings suggest that parasite-mediated selection may contribute to maintenance of phenotypes with high corticosterone responsiveness to stress, despite potential negative behavioural consequences.
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Affiliation(s)
- Elin Sild
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia
| | - Richard Meitern
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia
| | - Marju Männiste
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia
| | - Ulvi Karu
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia
| | - Peeter Hõrak
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia.
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Coon CAC, Brace AJ, McWilliams SR, McCue MD, Martin LB. Introduced and Native Congeners Use Different Resource Allocation Strategies to Maintain Performance during Infection. Physiol Biochem Zool 2014; 87:559-67. [DOI: 10.1086/676310] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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41
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Meitern R, Andreson R, Hõrak P. Profile of whole blood gene expression following immune stimulation in a wild passerine. BMC Genomics 2014; 15:533. [PMID: 24972896 PMCID: PMC4092216 DOI: 10.1186/1471-2164-15-533] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Accepted: 06/24/2014] [Indexed: 12/22/2022] Open
Abstract
Background Immunoecology aims to explain variation among hosts in the strength and efficacy of immunological defences in natural populations. This requires development of biomarkers of the activation of the immune system so that they can be collected non-lethally and sampled from small amounts of easily obtainable tissue. We used transcriptome profiling in wild greenfinches (Carduelis chloris) to detect whole blood transcripts that most profoundly indicate upregulation of antimicrobial defences during acute phase response. The more general aim of this study was to obtain a functional annotation of a substantial portion of the greenfinch transcriptome that would enable to gain access to more specific genomic tools in subsequent studies. The birds received either bacterial lipopolysaccharide or saline injections and RNA-seq transcriptional profiling was performed 12 h after treatment to provide initial functional annotation of the transcriptome and assess whole blood response to immune stimulation. Results A total of 66,084 transcripts were obtained from de novo Trinty assembly, out of which 23,153 could be functionally annotated. Only 1,911 of these were significantly upregulated or downregulated. The manipulation caused marked upregulation of several transcripts related to immune activation. These included avian-specific antimicrobial agents avidin and gallinacin, but also some more general host response genes, such as serum amyloid A protein, lymphocyte antigen 75 and copper-transporting ATPase 1. However, links with avian immunity for most differentially regulated transcripts remained rather hypothetical, as a large set of differentially expressed transcripts lacked functional annotation. Conclusions This appears to be the first large scale transcriptional profiling of immune function in passerine birds. The transcriptomic data obtained suggest novel markers for the assessment of the immunological state of wild passerines. Characterizing the function of those possible novel infection markers would assist future vertebrate genome annotation. The extensive sequence information collected enables to identify possible target and housekeeping genes needed to gain access to more specific genomic tools in future studies. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-533) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Richard Meitern
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Vanemuise 46, 51014 Tartu, Estonia.
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Kohl KD, Dearing MD. Wild-caught rodents retain a majority of their natural gut microbiota upon entrance into captivity. ENVIRONMENTAL MICROBIOLOGY REPORTS 2014; 6:191-5. [PMID: 24596293 DOI: 10.1111/1758-2229.12118] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 10/22/2013] [Indexed: 05/20/2023]
Abstract
Experiments conducted on captive animals allow scientists to control many variables; however, these settings are highly unnatural. Previous research has documented a large difference in microbial communities between wild animals and captive-bred individuals. However, wild-caught animals brought into captivity might retain their natural microbiota and thus provide a better study system in which to investigate the ecology of the gut microbiome. We collected individuals of the desert woodrat (Neotoma lepida) from nature and investigated changes in the microbial community over 6 months in captivity. Additionally, we inventoried potential environmental sources of microbes (food, bedding) from the wild and captivity. We found that environmental sources do not make large contributions to the woodrat gut microbial community. We documented a slight decrease in several biodiversity metrics over 6 months in captivity, yet the magnitude of change was small compared with other studies. Wild and captive animals shared 64% of their microbial species, almost twice that observed in other studies of wild and captive-bred individuals (≤ 37% shared). We conclude that wild-caught animals brought into captivity retain a substantial proportion of their natural microbiota and represent an acceptable system in which to study the gut microbiome.
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Affiliation(s)
- Kevin D Kohl
- Department of Biology, University of Utah, 257 South 1400 East, Salt Lake City, UT, 84112, USA
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Ekblom R, Wennekes P, Horsburgh GJ, Burke T. Characterization of the house sparrow (Passer domesticus) transcriptome: a resource for molecular ecology and immunogenetics. Mol Ecol Resour 2014; 14:636-46. [PMID: 24345231 DOI: 10.1111/1755-0998.12213] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Revised: 12/04/2013] [Accepted: 12/11/2013] [Indexed: 11/30/2022]
Abstract
The house sparrow (Passer domesticus) is an important model species in ecology and evolution. However, until recently, genomic resources for molecular ecological projects have been lacking in this species. Here, we present transcriptome sequencing data (RNA-Seq) from three different house sparrow tissues (spleen, blood and bursa). These tissues were specifically chosen to obtain a diverse representation of expressed genes and to maximize the yield of immune-related gene functions. After de novo assembly, 15,250 contigs were identified, representing sequence data from a total of 8756 known avian genes (as inferred from the closely related zebra finch). The transcriptome assembly contain sequence data from nine manually annotated MHC genes, including an almost complete MHC class I coding sequence. There were 407, 303 and 68 genes overexpressed in spleen, blood and bursa, respectively. Gene ontology terms related to ribosomal function were associated with overexpression in spleen and oxygen transport functions with overexpression in blood. In addition to the transcript sequences, we provide 327 gene-linked microsatellites (SSRs) with sufficient flanking sequences for primer design, and 3177 single-nucleotide polymorphisms (SNPs) within genes, that can be used in follow-up molecular ecology studies of this ecological well-studied species.
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Affiliation(s)
- Robert Ekblom
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18 D, Uppsala, SE-75236, Sweden; Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
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Martin LB, Coon CAC, Liebl AL, Schrey AW. Surveillance for microbes and range expansion in house sparrows. Proc Biol Sci 2013; 281:20132690. [PMID: 24258722 DOI: 10.1098/rspb.2013.2690] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Interactions between hosts and parasites influence the success of host introductions and range expansions post-introduction. However, the physiological mechanisms mediating these outcomes are little known. In some vertebrates, variation in the regulation of inflammation has been implicated, perhaps because inflammation imparts excessive costs, including high resource demands and collateral damage upon encounter with novel parasites. Here, we tested the hypothesis that variation in the regulation of inflammation contributed to the spread of house sparrows (Passer domesticus) across Kenya, one of the world's most recent invasions of this species. Specifically, we asked whether inflammatory gene expression declines with population age (i.e. distance from Mombasa (dfM), the site of introduction around 1950). We compared expression of two microbe surveillance molecules (Toll-like receptors, TLRs-2 and 4) and a proinflammatory cytokine (interleukin-6, IL-6) before and after an injection of an immunogenic component of Gram-negative bacteria (lipopolysaccharide, LPS) among six sparrow populations. We then used a best-subset model selection approach to determine whether population age (dfM) or other factors (e.g. malaria or coccidian infection, sparrow density or genetic group membership) best-explained gene expression. For baseline expression of TLR-2 and TLR-4, population age tended to be the best predictor with expression decreasing with population age, although other factors were also important. Induced expression of TLRs was affected by LPS treatment alone. For induced IL-6, only LPS treatment reliably predicted expression; baseline expression was not explained by any factor. These data suggest that changes in microbe surveillance, more so than downstream control of inflammation via cytokines, might have been important to the house sparrow invasion of Kenya.
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Affiliation(s)
- Lynn B Martin
- Department of Integrative Biology, University of South Florida, , SCA 110, Tampa, FL 33620, USA, Department of Biology, Armstrong Atlantic State University, , Savannah, GA 31419, USA
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Meitern R, Sild E, Lind MA, Männiste M, Sepp T, Karu U, Hõrak P. Effects of Endotoxin and Psychological Stress on Redox Physiology, Immunity and Feather Corticosterone in Greenfinches. PLoS One 2013; 8:e67545. [PMID: 23805316 PMCID: PMC3689720 DOI: 10.1371/journal.pone.0067545] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 05/20/2013] [Indexed: 12/24/2022] Open
Abstract
Assessment of costs accompanying activation of immune system and related neuroendocrine pathways is essential for understanding the selective forces operating on these systems. Here we attempted to detect such costs in terms of disruption to redox balance and interference between different immune system components in captive wild-caught greenfinches (Carduelis chloris). Study birds were subjected to an endotoxin-induced inflammatory challenge and temporary exposure to a psychological stressor (an image of a predator) in a 2*2 factorial experiment. Injection of bacterial endotoxin resulted in up-regulation of two markers of antioxidant protection – erythrocyte glutathione, and plasma oxygen radical absorbance (OXY). These findings suggest that inflammatory responses alter redox homeostasis. However, no effect on markers of oxidative damage to proteins or DNA in erythrocytes could be detected. We found no evidence that the endotoxin injection interfered with antibody production against Brucella abortus antigen or the intensity of chronic coccidiosis. The hypothesis of within-immune system trade-offs as a cost of immunity was thus not supported in our model system. We showed for the first time that administration of endotoxin can reduce the level of corticosterone deposited into feathers. This finding suggests a down-regulation of the corticosterone secretion cascade due to an endotoxin-induced immune response, a phenomenon that has not been reported previously. Exposure to the predator image did not affect any of the measured physiological parameters.
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Affiliation(s)
- Richard Meitern
- Department of Zoology, Institute of Ecology and Earth Sciences, Tartu University, Tartu, Estonia
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Männiste M, Sepp T, Hõrak P. Locomotor Activity of Captive Greenfinches Involves Two Different Behavioural Traits. Ethology 2013. [DOI: 10.1111/eth.12099] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marju Männiste
- Department of Zoology; Institute of Ecology and Earth Sciences; Tartu University; Tartu; Estonia
| | - Tuul Sepp
- Department of Zoology; Institute of Ecology and Earth Sciences; Tartu University; Tartu; Estonia
| | - Peeter Hõrak
- Department of Zoology; Institute of Ecology and Earth Sciences; Tartu University; Tartu; Estonia
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Previtali MA, Ostfeld RS, Keesing F, Jolles AE, Hanselmann R, Martin LB. Relationship between pace of life and immune responses in wild rodents. OIKOS 2012. [DOI: 10.1111/j.1600-0706.2012.020215.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Martin LB, Brace A, Urban A, Coon CAC, Liebl AL. Does immune suppression during stress occur to promote physical performance? J Exp Biol 2012; 215:4097-103. [DOI: 10.1242/jeb.073049] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Summary
Two adaptationist hypotheses have been proposed to explain why stress, particularly elevation of stress hormones (i.e., glucocorticoids), tends to suppress immune functions. One is that immune suppression represents efforts to minimize autoimmune responses to self-antigens released as organisms cope with stressors (i.e., the autoimmune-avoidance hypothesis). The other is that immune suppression occurs to promote a shunting of resources to life processes more conducive to survival of the stressor (i.e., the re-allocation hypothesis). Here in wild-caught house sparrows (Passer domesticus), we tested the second hypothesis, asking whether sustained elevation of baseline glucocorticoids, due to captivity, caused a greater rate of decline in immune functions than flight performance. A greater decline in immune functions than flight performance would support the re-allocation hypothesis. As in previous studies, we found that captivity tended to alter baseline corticosterone, suggesting that house sparrows experience captivity as a stressor. Captivity also affected several constitutive and induced innate immune metrics: bacterial (Escherichia coli) killing activity (BKA) of blood and oxidative burst of leukocytes both changed in a manner consistent with immune disregulation. In contrast, breast muscle size and vertical flight (hovering) duration improved over captivity. Collectively, these changes provide indirect support for the re-allocation hypothesis, although within individuals, changes in immune and physical performance were unrelated.
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