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Bacigalupe LD, Solano‐Iguaran JJ, Longo AV, Gaitán‐Espitia JD, Valenzuela‐Sánchez A, Alvarado‐Rybak M, Azat C. Nor climate nor human impact factors: Chytrid infection shapes the skin bacterial communities of an endemic amphibian in a biodiversity hotspot. Ecol Evol 2024; 14:e11249. [PMID: 38590552 PMCID: PMC10999949 DOI: 10.1002/ece3.11249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 03/27/2024] [Indexed: 04/10/2024] Open
Abstract
The bacterial communities of the amphibian skin (i.e., the bacteriome) are critical to the host's innate immune system. However, it is unclear how different drivers can alter this function by modulating the bacteriome's structure. Our aim was to assess the extent to which different host attributes and extrinsic factors influence the structure of the bacterial communities of the skin. Skin bacterial diversity was examined in 148 individuals of the four-eyed frog (Pleurodema thaul) from 16 localities spanning almost 1800 km in latitude. The richness and beta diversity of bacterial families and the richness and abundance of Bd-inhibitory bacterial genera were used to describe their structure. Predictors associated with the host (developmental stage, genetic lineage, individual Batrachochytrium dendrobatidis [Bd] infection status) and the landscape (current climate, degree of anthropogenic disturbance) were used in the statistical modeling in an information theoretical approach. Bd infection and host developmental stage were the only predictors affecting bacteriome richness, with Bd+ individuals and postmetamorphic stages (adults and juveniles) having higher richness than Bd- ones and tadpoles. High diversity in Bd+ individuals is not driven by bacterial genera with known anti-Bd properties. Beta diversity was not affected by Bd infection and was mainly a consequence of bacterial family turnover rather than nestedness. Finally, for those bacterial genera known to have inhibitory effects on chytrid, Bd+ individuals had a slightly higher diversity than Bd- ones. Our study confirms an association between Bd infection and the host developmental stage with the bacterial communities of the skin of P. thaul. Unexpectedly, macroclimate and human impact factors do not seem to play a role in shaping the amphibian skin microbiome. Our study exemplifies that focusing on a single host-parasite system over a large geographic scale can provide essential insights into the factors driving host-parasite-bacteriome interactions.
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Affiliation(s)
| | - Jaiber J. Solano‐Iguaran
- Instituto de Ciencias Ambientales y EvolutivasUniversidad Austral de ChileValdiviaChile
- Departamento de Salud HidrobiológicaInstituto de Fomento PesqueroPuerto MonttChile
| | - Ana V. Longo
- Department of BiologyUniversity of FloridaGainesvilleFloridaUSA
| | - Juan D. Gaitán‐Espitia
- School of Biological Sciences and the SWIRE Institute of Marine ScienceThe University of Hong KongHong KongSARChina
| | | | - Mario Alvarado‐Rybak
- Núcleo de Ciencias Aplicadas en Ciencias Veterinarias y AgronómicasUniversidad de Las AméricasSantiagoChile
| | - Claudio Azat
- Sustainability Research Centre & PhD in Conservation MedicineUniversidad Andres BelloSantiagoChile
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2
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Thumsová B, González-Miras E, Rubio Á, Granados I, Bates KA, Bosch J. Chemical disinfection as a simple and reliable method to control the amphibian chytrid fungus at breeding points of endangered amphibians. Sci Rep 2024; 14:5151. [PMID: 38431740 PMCID: PMC10908824 DOI: 10.1038/s41598-024-55946-1] [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: 11/27/2023] [Accepted: 02/29/2024] [Indexed: 03/05/2024] Open
Abstract
Chytridiomycosis caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd) is pushing amphibians towards extinction. Whilst mitigation methods were suggested a decade ago, we lack field trials testing their efficacy. We used the agrochemical fungicide, tebuconazole, to treat Bd infected breeding waterbodies of an endangered species that is highly susceptible to the fungus. Just two applications of tebuconazole led to a significant reduction in infection loads in the vast majority of sites, and at six sites the disinfection remained one/two-years post-application. Tebuconazole values drastically decreased in the waterbodies within a week after application, with no significant effects on their hydrochemical and hydrobiological characteristics. Although the use of chemicals in natural populations is undesirable, the growing existential threat to amphibians all over the world indicates that effective interventions in selected populations of endangered species are urgently needed.
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Affiliation(s)
- Barbora Thumsová
- Asociación Herpetológica Española (AHE), Madrid, Spain
- Museo Nacional de Ciencias Naturales-CSIC, 28006, Madrid, Spain
- IMIB-Research Unit of Biodiversity (University of Oviedo, CSIC, Principality of Asturias), 33600, Mieres, Spain
| | - Emilio González-Miras
- Agencia de Medio Ambiente y Agua de Andalucía, Consejería de Sostenibilidad, Medio Ambiente y Economía Azul, Junta de Andalucía, Seville, Spain
| | - Ángel Rubio
- Centro de Investigación, Seguimiento y Evaluación, Parque Nacional Sierra de Guadarrama, 28740, Rascafría, Spain
| | - Ignacio Granados
- Centro de Investigación, Seguimiento y Evaluación, Parque Nacional Sierra de Guadarrama, 28740, Rascafría, Spain
| | - Kieran A Bates
- Centre for Immunobiology, The Blizard Institute, Queen Mary University of London, London, E1 2AT, UK
| | - Jaime Bosch
- IMIB-Research Unit of Biodiversity (University of Oviedo, CSIC, Principality of Asturias), 33600, Mieres, Spain.
- Centro de Investigación, Seguimiento y Evaluación, Parque Nacional Sierra de Guadarrama, 28740, Rascafría, Spain.
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3
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Berger L, Skerratt LF, Kosch TA, Brannelly LA, Webb RJ, Waddle AW. Advances in Managing Chytridiomycosis for Australian Frogs: Gradarius Firmus Victoria. Annu Rev Anim Biosci 2024; 12:113-133. [PMID: 38358840 DOI: 10.1146/annurev-animal-021122-100823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Extensive knowledge gains from research worldwide over the 25 years since the discovery of chytridiomycosis can be used for improved management. Strategies that have saved populations in the short term and/or enabled recovery include captive breeding, translocation into disease refugia, translocation from resistant populations, disease-free exclosures, and preservation of disease refuges with connectivity to previous habitat, while antifungal treatments have reduced mortality rates in the wild. Increasing host resistance is the goal of many strategies under development, including vaccination and targeted genetic interventions. Pathogen-directed strategies may be more challenging but would have broad applicability. While the search for the silver bullet solution continues, we should value targeted local interventions that stop extinction and buy time for evolution of resistance or development of novel solutions. As for most invasive species and infectious diseases, we need to accept that ongoing management is necessary. For species continuing to decline, proactive deployment and assessment of promising interventions are more valid than a hands-off, do-no-harm approach that will likely allow further extinctions.
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Affiliation(s)
- Lee Berger
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Lee F Skerratt
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Tiffany A Kosch
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Laura A Brannelly
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Rebecca J Webb
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
| | - Anthony W Waddle
- One Health Research Group, Melbourne Veterinary School, Faculty of Science, University of Melbourne, Werribee, Victoria, Australia; , , , ,
- Applied Biosciences, Macquarie University, Sydney, New South Wales, Australia;
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4
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Ujszegi J, Boros Z, Fodor A, Vajna B, Hettyey A. Metabolites of Xenorhabdus bacteria are potent candidates for mitigating amphibian chytridiomycosis. AMB Express 2023; 13:88. [PMID: 37615904 PMCID: PMC10449739 DOI: 10.1186/s13568-023-01585-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 07/20/2023] [Indexed: 08/25/2023] Open
Abstract
Chytridiomycosis, caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd), has caused extreme losses in amphibian biodiversity. Finding bacteria that produce metabolites with antifungal properties may turn out to be invaluable in the fight against this devastating disease. The entomopathogenic bacteria, Xenorhabdus szentirmaii and X. budapestensis produce secondary metabolites that are effective against a wide range of fungal plant pathogens. To assess whether they may also be effective against Bd, we extracted cell-free culture media (CFCM) from liquid cultures of X. szentirmaii and X. budapestensis and tested their ability to inhibit Bd growth in vitro. As a second step, using juvenile common toads (Bufo bufo) experimentally infected with Bd we also tested the in vivo antifungal efficacy of X. szentirmaii CFCM diluted to 2 and 10% (v/v), while also assessing possible malign side effects on amphibians. Results of the in vitro experiment documented highly effective growth inhibition by CFCMs of both Xenorhabdus species. The in vivo experiment showed that treatment with CFCM of X. szentirmaii applied at a dilution of 10% resulted in infection intensities reduced by ca. 73% compared to controls and to juvenile toads treated with CFCM applied at a dilution of 2%. At the same time, we detected no negative side effects of treatment with CFCM on toad survival and development. Our results clearly support the idea that metabolites of X. szentirmaii, and perhaps of several other Xenorhabdus species as well, may prove highly useful for the treatment of Bd infected amphibians.
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Affiliation(s)
- János Ujszegi
- Department of Evolutionary Ecology, Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network, Budapest, Hungary.
- Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary.
| | - Zsófia Boros
- Department of Evolutionary Ecology, Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network, Budapest, Hungary
- Department of Genetics, Eötvös Loránd University, Budapest, Hungary
- Department of Microbiology, Eötvös Loránd University, Budapest, Hungary
| | - András Fodor
- Department of Genetics, Eötvös Loránd University, Budapest, Hungary
| | - Balázs Vajna
- Department of Microbiology, Eötvös Loránd University, Budapest, Hungary
| | - Attila Hettyey
- Department of Evolutionary Ecology, Plant Protection Institute, Centre for Agricultural Research, Eötvös Loránd Research Network, Budapest, Hungary
- Department of Systematic Zoology and Ecology, Eötvös Loránd University, Budapest, Hungary
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5
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Vahedi SM, Salek Ardetani S, Brito LF, Karimi K, Pahlavan Afshari K, Banabazi MH. Expanding the application of haplotype-based genomic predictions to the wild: A case of antibody response against Teladorsagia circumcincta in Soay sheep. BMC Genomics 2023; 24:335. [PMID: 37330501 DOI: 10.1186/s12864-023-09407-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 05/24/2023] [Indexed: 06/19/2023] Open
Abstract
BACKGROUND Genomic prediction of breeding values (GP) has been adopted in evolutionary genomic studies to uncover microevolutionary processes of wild populations or improve captive breeding strategies. While recent evolutionary studies applied GP with individual single nucleotide polymorphism (SNP), haplotype-based GP could outperform individual SNP predictions through better capturing the linkage disequilibrium (LD) between the SNP and quantitative trait loci (QTL). This study aimed to evaluate the accuracy and bias of haplotype-based GP of immunoglobulin (Ig) A (IgA), IgE, and IgG against Teladorsagia circumcincta in lambs of an unmanaged sheep population (Soay breed) based on Genomic Best Linear Unbiased Prediction (GBLUP) and five Bayesian [BayesA, BayesB, BayesCπ, Bayesian Lasso (BayesL), and BayesR] methods. RESULTS The accuracy and bias of GPs using SNP, haplotypic pseudo-SNP from blocks with different LD thresholds (0.15, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.00), or the combinations of pseudo-SNPs and non-LD clustered SNPs were obtained. Across methods and marker sets, higher ranges of genomic estimated breeding values (GEBV) accuracies were observed for IgA (0.20 to 0.49), followed by IgE (0.08 to 0.20) and IgG (0.05 to 0.14). Considering the methods evaluated, up to 8% gains in GP accuracy of IgG were achieved using pseudo-SNPs compared to SNPs. Up to 3% gain in GP accuracy for IgA was also obtained using the combinations of the pseudo-SNPs with non-clustered SNPs in comparison to fitting individual SNP. No improvement in GP accuracy of IgE was observed using haplotypic pseudo-SNPs or their combination with non-clustered SNPs compared to individual SNP. Bayesian methods outperformed GBLUP for all traits. Most scenarios yielded lower accuracies for all traits with an increased LD threshold. GP models using haplotypic pseudo-SNPs predicted less-biased GEBVs mainly for IgG. For this trait, lower bias was observed with higher LD thresholds, whereas no distinct trend was observed for other traits with changes in LD. CONCLUSIONS Haplotype information improves GP performance of anti-helminthic antibody traits of IgA and IgG compared to fitting individual SNP. The observed gains in the predictive performances indicate that haplotype-based methods could benefit GP of some traits in wild animal populations.
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Affiliation(s)
- Seyed Milad Vahedi
- Department of Animal Science and Aquaculture, Dalhousie University, Truro, NS, B2N5E3, Canada
| | | | - Luiz F Brito
- Department of Animal Sciences, Purdue University, West Lafayette, IN, 47907, USA
| | - Karim Karimi
- Molecular Diagnostics Program, Verspeeten Clinical Genome Centre, London Health Sciences Centre, London, ON, N6A 5W9, Canada
| | - Kian Pahlavan Afshari
- Department of Animal Sciences, Islamic Azad University, Varamin, Varamin-Pishva Branch3381774895, Iran
| | - Mohammad Hossein Banabazi
- Department of Animal Breeding and Genetics (HGEN), Centre for Veterinary Medicine and Animal Science (VHC), Swedish University of Agricultural Sciences (SLU), 75007, Uppsala, Sweden.
- Department of Biotechnology, Animal Science Research Institute of IRAN (ASRI), Agricultural Research, Education & Extension Organization (AREEO), Karaj, 3146618361, Iran.
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6
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Kaganer AW, Ossiboff RJ, Keith NI, Schuler KL, Comizzoli P, Hare MP, Fleischer RC, Gratwicke B, Bunting EM. Immune priming prior to pathogen exposure sheds light on the relationship between host, microbiome and pathogen in disease. ROYAL SOCIETY OPEN SCIENCE 2023; 10:220810. [PMID: 36756057 PMCID: PMC9890126 DOI: 10.1098/rsos.220810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Dynamic interactions between host, pathogen and host-associated microbiome dictate infection outcomes. Pathogens including Batrachochytrium dendrobatidis (Bd) threaten global biodiversity, but conservation efforts are hindered by limited understanding of amphibian host, Bd and microbiome interactions. We conducted a vaccination and infection experiment using Eastern hellbender salamanders (Cryptobranchus alleganiensis alleganiensis) challenged with Bd to observe infection, skin microbial communities and gene expression of host skin, pathogen and microbiome throughout the experiment. Most animals survived high Bd loads regardless of their vaccination status and vaccination did not affect pathogen load, but host gene expression differed based on vaccination. Oral vaccination (exposure to killed Bd) stimulated immune gene upregulation while topically and sham-vaccinated animals did not significantly upregulate immune genes. In early infection, topically vaccinated animals upregulated immune genes but orally and sham-vaccinated animals downregulated immune genes. Bd increased pathogenicity-associated gene expression in late infection when Bd loads were highest. The microbiome was altered by Bd, but there was no correlation between anti-Bd microbe abundance or richness and pathogen burden. Our observations suggest that hellbenders initially generate a vigorous immune response to Bd, which is ineffective at controlling disease and is subsequently modulated. Interactions with antifungal skin microbiota did not influence disease progression.
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Affiliation(s)
- Alyssa W. Kaganer
- Department of Natural Resources and the Environment, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, 14853, USA
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, 20008, USA
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
| | - Robert J. Ossiboff
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- Department of Comparative, Diagnostic, and Population Medicine, College of Veterinary Medicine, University of Florida, Gainesville, FL, 32611, USA
| | - Nicole I. Keith
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
- Biology Department, Hamilton College, Clinton, NY, 13323, USA
| | - Krysten L. Schuler
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
| | - Pierre Comizzoli
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, 20008, USA
| | - Matthew P. Hare
- Department of Natural Resources and the Environment, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, 14853, USA
| | - Robert C. Fleischer
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, 20008, USA
| | - Brian Gratwicke
- Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, VA, 22630, USA
| | - Elizabeth M. Bunting
- Cornell Wildlife Health Laboratory, Animal Health Diagnostic Center, Cornell University, Ithaca, NY, 14853, USA
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, 14853, USA
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7
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Efficacy of Plant-Derived Fungicides at Inhibiting Batrachochytrium salamandrivorans Growth. J Fungi (Basel) 2022; 8:jof8101025. [PMID: 36294589 PMCID: PMC9605044 DOI: 10.3390/jof8101025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 09/23/2022] [Accepted: 09/27/2022] [Indexed: 11/21/2022] Open
Abstract
The emerging fungal amphibian pathogen, Batrachochytrium salamandrivorans (Bsal), is currently spreading across Europe and given its estimated invasion potential, has the capacity to decimate salamander populations worldwide. Fungicides are a promising in situ management strategy for Bsal due to their ability to treat the environment and infected individuals. However, antifungal drugs or pesticides could adversely affect the environment and non-target hosts, thus identifying safe, effective candidate fungicides for in situ treatment is needed. Here, we estimated the inhibitory fungicidal efficacy of five plant-derived fungicides (thymol, curcumin, allicin, 6-gingerol, and Pond Pimafix®) and one chemical fungicide (Virkon® Aquatic) against Bsal zoospores in vitro. We used a broth microdilution method in 48-well plates to test the efficacy of six concentrations per fungicide on Bsal zoospore viability. Following plate incubation, we performed cell viability assays and agar plate growth trials to estimate the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of each fungicide. All six fungicides exhibited inhibitory and fungicidal effects against Bsal growth, with estimated MIC concentrations ranging from 60 to 0.156 μg/mL for the different compounds. Allicin showed the greatest efficacy (i.e., lowest MIC and MFC) against Bsal zoospores followed by curcumin, Pond Pimafix®, thymol, 6-gingerol, and Virkon® Aquatic, respectively. Our results provide evidence that plant-derived fungicides are effective at inhibiting and killing Bsal zoospores in vitro and may be useful for in situ treatment. Additional studies are needed to estimate the efficacy of these fungicides at inactivating Bsal in the environment and treating Bsal-infected amphibians.
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8
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Carver S, Peters A, Richards SA. Model Integrated Disease Management to facilitate effective translatable solutions for wildlife disease issues. J Appl Ecol 2022. [DOI: 10.1111/1365-2664.14298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Scott Carver
- Department of Biological Sciences University of Tasmania
| | - Andrew Peters
- School of Animal and Veterinary Sciences Charles Sturt University
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9
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Cook K, Pope K, Cummings A, Piovia‐Scott J. In situ treatment of juvenile frogs for disease can reverse population declines. CONSERVATION SCIENCE AND PRACTICE 2022. [DOI: 10.1111/csp2.12762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Affiliation(s)
- Kimberly Cook
- School of Biological Sciences Washington State University Vancouver WA USA
| | - Karen Pope
- Pacific Southwest Research Station United States Forest Service California USA
| | - Adam Cummings
- Pacific Southwest Research Station United States Forest Service California USA
| | - Jonah Piovia‐Scott
- School of Biological Sciences Washington State University Vancouver WA USA
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10
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Estrada A, Medina D, Gratwicke B, Ibáñez R, Belden LK. Body condition, skin bacterial communities and disease status: insights from the first release trial of the limosa harlequin frog,
Atelopus limosus. Proc Biol Sci 2022; 289:20220586. [PMID: 35858072 PMCID: PMC9277274 DOI: 10.1098/rspb.2022.0586] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Many endangered amphibian species survive in captive breeding facilities, but there have been few attempts to reintroduce captive-born individuals to rebuild wild populations. We conducted a soft-release trial of limosa harlequin frogs,
Atelopus limosus,
which are highly susceptible to the amphibian chytrid fungus
Batrachochytrium dendrobatidis
(Bd), to understand changes associated with the transition from captivity to the wild. Specifically, we assessed changes in body condition, skin-associated bacterial communities and disease status after release. Frogs were housed individually in field mesocosms and monitored for 27 days. Body condition did not significantly change in the mesocosms, and was similar to, or higher than, that of wild conspecifics at day 27. The skin bacteria of captive-born frogs, based on 16S rRNA gene amplicons, became similar to that of wild conspecifics after 27 days in mesocosms. Prevalence of Bd in wild conspecifics was 13–27%, and 15% of the
A. limosus
in mesocosms became infected with Bd, but no mortality of infected frogs was observed. We conclude that mesocosms are suitable for systematically and repeatedly monitoring amphibians during release trials, and that body condition, the skin microbiome, and Bd status can all change within one month of placement of captive-born individuals back into the wild.
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Affiliation(s)
- Angie Estrada
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061-0131, USA
| | - Daniel Medina
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061-0131, USA
- Smithsonian Tropical Research Institute, Panama City, Panama
- Sistema Nacional de Investigación, SENACYT, Panama
| | - Brian Gratwicke
- Smithsonian's National Zoo and Conservation Biology Institute, Front Royal, VA 22630, USA
| | - Roberto Ibáñez
- Smithsonian Tropical Research Institute, Panama City, Panama
- Sistema Nacional de Investigación, SENACYT, Panama
| | - Lisa K. Belden
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24061-0131, USA
- Smithsonian Tropical Research Institute, Panama City, Panama
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11
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Turner GG, Sewall BJ, Scafini MR, Lilley TM, Bitz D, Johnson JS. Cooling of bat hibernacula to mitigate white-nose syndrome. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2022; 36:e13803. [PMID: 34224186 DOI: 10.1111/cobi.13803] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/09/2021] [Accepted: 06/22/2021] [Indexed: 06/13/2023]
Abstract
White-nose syndrome (WNS) is a fungal disease that has caused precipitous declines in several North American bat species, creating an urgent need for conservation. We examined how microclimates and other characteristics of hibernacula have affected bat populations following WNS-associated declines and evaluated whether cooling of warm, little-used hibernacula could benefit bats. During the period following mass mortality (2013-2020), we conducted 191 winter surveys of 25 unmanipulated hibernacula and 6 manipulated hibernacula across Pennsylvania (USA). We joined these data with additional datasets on historical (pre-WNS) bat counts and on the spatial distribution of underground sites. We used generalized linear mixed models and model selection to identify factors affecting bat populations. Winter counts of Myotis lucifugus were higher and increased over time in colder hibernacula (those with midwinter temperatures of 3-6 °C) compared with warmer (7-11 °C) hibernacula. Counts of Eptesicus fuscus, Myotis leibii, and Myotis septentrionalis were likewise higher in colder hibernacula (temperature effects = -0.73 [SE 0.15], -0.51 [0.18], and -0.97 [0.28], respectively). Populations of M. lucifugus and M. septentrionalis increased most over time in hibernacula surrounded by more nearby sites, whereas Eptesicus fuscus counts remained high where they had been high before WNS onset (pre-WNS high count effect = 0.59 [0.22]). Winter counts of M. leibii were higher in hibernacula with high vapor pressure deficits (VPDs) (particularly over 0.1 kPa) compared with sites with lower VPDs (VPD effect = 15.3 [4.6]). Counts of M. lucifugus and E. fuscus also appeared higher where VPD was higher. In contrast, Perimyotis subflavus counts increased over time in relatively warm hibernacula and were unaffected by VPD. Where we manipulated hibernacula, we achieved cooling of on average 2.1 °C. At manipulated hibernacula, counts of M. lucifugus and P. subflavus increased over time (years since manipulation effect = 0.70 [0.28] and 0.51 [0.15], respectively). Further, there were more E. fuscus where cooling was greatest (temperature difference effect = -0.46 [SE 0.11]), and there was some evidence there were more P. subflavus in hibernacula sections that remained warm after manipulation. These data show bats are responding effectively to WNS through habitat selection. In M. lucifugus, M. septentrionalis, and possibly P. subflavus, this response is ongoing, with bats increasingly aggregating at suitable hibernacula, whereas E. fuscus remain in previously favored sites. Our results suggest that cooling warm sites receiving little use by bats is a viable strategy for combating WNS.
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Affiliation(s)
| | - Brent J Sewall
- Department of Biology, Temple University, Philadelphia, Pennsylvania, USA
| | | | - Thomas M Lilley
- Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - Daniel Bitz
- CNX Gas Company LLC, Canonsburg, Pennsylvania, USA
| | - Joseph S Johnson
- Department of Biological Sciences, Ohio University, Athens, Ohio, USA
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12
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Hardy BM, Muths E, Koons DN. Context-dependent variation in persistence of host populations in the face of disease. J Anim Ecol 2022; 91:282-286. [PMID: 35112351 DOI: 10.1111/1365-2656.13654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 12/07/2021] [Indexed: 11/28/2022]
Abstract
Research Highlight: Valenzuela-Sánchez, A., Azat, C., Cunningham, A. A., Delgado, S., Bacigalupe, L. D., Beltrand, J., Serrano, J. M., Sentenac, H., Haddow, N., Toledo, V., Schmidt, B. R., & Cayuela, H. (2022). Interpopulation differences in male reproductive effort drive the population dynamics of a host exposed to an emerging fungal pathogen. Journal of Animal Ecology, 00, 1- 12. https://doi.org/10.1111/1365-2656.13603. Understanding the nuances of population persistence in the face of a stressor can help predict extinction risk and guide conservation actions. However, the exact mechanisms driving population stability may not always be known. In this paper, Valenzuela-Sánchez et al. (2022) integrate long-term mark-recapture data, focal measurements of reproductive effort, a population matrix model and inferences on life-history variation to reveal differences in demographic response to disease in a susceptible frog species (Rhinoderma darwinii). Valenzuela-Sánchez et al. found that demographic compensation via recruitment explained the positive population growth rate in their high disease prevalence population whereas the low disease prevalence population did not compensate and thus had decreasing population growth. Compensatory recruitment was likely due to the high probability of males brooding, and the high number of brooded larvae in the high prevalence population compared to low prevalence and disease-free populations. Valenzuela-Sánchez et al. also document faster generation times in the high prevalence population, which may indicate a faster life history that may be contributing to the population's ability to compensate for reduced survival. Lastly, the authors find a positive relationship between disease prevalence and the proportion of juveniles in a given population that suggest that there may be a threshold for disease prevalence that triggers increased reproductive effort. Altogether, their study provides novel support for increased reproductive effort as the pathway for compensatory recruitment leading to increasing population growth despite strong negative effects of disease on adult survival. Their results also caution the overgeneralization of the effects of stressors (e.g. disease) on population dynamics, where context-dependent responses may differ among host populations of a given species.
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Affiliation(s)
- Bennett M Hardy
- Department of Fish, Wildlife and Conservation Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
| | - Erin Muths
- U.S. Geological Survey, Fort Collins Science Center, Fort Collins, CO, USA
| | - David N Koons
- Department of Fish, Wildlife and Conservation Biology and Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO, USA
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13
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Knapp RA, Joseph MB, Smith TC, Hegeman EE, Vredenburg VT, Erdman Jr JE, Boiano DM, Jani AJ, Briggs CJ. Effectiveness of antifungal treatments during chytridiomycosis epizootics in populations of an endangered frog. PeerJ 2022; 10:e12712. [PMID: 35036095 PMCID: PMC8742549 DOI: 10.7717/peerj.12712] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 12/09/2021] [Indexed: 01/07/2023] Open
Abstract
The recently-emerged amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) has had an unprecedented impact on global amphibian populations, and highlights the urgent need to develop effective mitigation strategies. We conducted in-situ antifungal treatment experiments in wild populations of the endangered mountain yellow-legged frog during or immediately after Bd-caused mass die-off events. The objective of treatments was to reduce Bd infection intensity ("load") and in doing so alter frog-Bd dynamics and increase the probability of frog population persistence despite ongoing Bd infection. Experiments included treatment of early life stages (tadpoles and subadults) with the antifungal drug itraconazole, treatment of adults with itraconazole, and augmentation of the skin microbiome of subadults with Janthinobacterium lividum, a commensal bacterium with antifungal properties. All itraconazole treatments caused immediate reductions in Bd load, and produced longer-term effects that differed between life stages. In experiments focused on early life stages, Bd load was reduced in the 2 months immediately following treatment and was associated with increased survival of subadults. However, Bd load and frog survival returned to pre-treatment levels in less than 1 year, and treatment had no effect on population persistence. In adults, treatment reduced Bd load and increased frog survival over the entire 3-year post-treatment period, consistent with frogs having developed an effective adaptive immune response against Bd. Despite this protracted period of reduced impacts of Bd on adults, recruitment into the adult population was limited and the population eventually declined to near-extirpation. In the microbiome augmentation experiment, exposure of subadults to a solution of J. lividum increased concentrations of this potentially protective bacterium on frogs. However, concentrations declined to baseline levels within 1 month and did not have a protective effect against Bd infection. Collectively, these results indicate that our mitigation efforts were ineffective in causing long-term changes in frog-Bd dynamics and increasing population persistence, due largely to the inability of early life stages to mount an effective immune response against Bd. This results in repeated recruitment failure and a low probability of population persistence in the face of ongoing Bd infection.
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Affiliation(s)
- Roland A. Knapp
- Sierra Nevada Aquatic Research Laboratory, University of California, Mammoth Lakes, California, United States
- Earth Research Institute, University of California, Santa Barbara, California, United States
| | | | - Thomas C. Smith
- Sierra Nevada Aquatic Research Laboratory, University of California, Mammoth Lakes, California, United States
- Earth Research Institute, University of California, Santa Barbara, California, United States
| | - Ericka E. Hegeman
- Sierra Nevada Aquatic Research Laboratory, University of California, Mammoth Lakes, California, United States
- Earth Research Institute, University of California, Santa Barbara, California, United States
| | - Vance T. Vredenburg
- Department of Biology, San Francisco State University, San Francisco, California, United States
| | - James E. Erdman Jr
- California Department of Fish and Wildlife, Bishop, California, United States
| | - Daniel M. Boiano
- Sequoia and Kings Canyon National Parks, National Park Service, Three Rivers, California, United States
| | - Andrea J. Jani
- Pacific Biosciences Research Center, University of Hawai’i at Mànoa, Honolulu, Hawai’i, United States
| | - Cheryl J. Briggs
- Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California, United States
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14
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Holt WV, Comizzoli P. Opportunities and Limitations for Reproductive Science in Species Conservation. Annu Rev Anim Biosci 2021; 10:491-511. [PMID: 34699258 DOI: 10.1146/annurev-animal-013120-030858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Reproductive science in the context of conservation biology is often understood solely in terms of breeding threatened species. Although technologies developed primarily for agriculture or biomedicine have a potentially important role in species conservation, their effectiveness is limited if we regard the main objective of animal conservation as helping to support populations rather than to breed a small number of individuals. The global threats facing wild species include the consequences of climate change, population growth, urbanization, atmospheric and water pollution, and the release of chemicals into the environment, to cite but a few. Reproductive sciences provide important and often unexpected windows into many of these consequences, and our aim here is both to demonstrate the breadth of reproductive science and the importance of basic knowledge and to suggest where some of the insights might be useful in mitigating the problems. Expected final online publication date for the Annual Review of Animal Biosciences, Volume 10 is February 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- William V Holt
- Academic Unit of Reproductive and Developmental Medicine, Department of Oncology & Metabolism, University of Sheffield, Sheffield, United Kingdom;
| | - Pierre Comizzoli
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, USA;
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15
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Koo MS, Vredenburg VT, Deck JB, Olson DH, Ronnenberg KL, Wake DB. Tracking, Synthesizing, and Sharing Global Batrachochytrium Data at AmphibianDisease.org. Front Vet Sci 2021; 8:728232. [PMID: 34692807 PMCID: PMC8527349 DOI: 10.3389/fvets.2021.728232] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 09/02/2021] [Indexed: 11/13/2022] Open
Abstract
Emerging infectious diseases have been especially devastating to amphibians, the most endangered class of vertebrates. For amphibians, the greatest disease threat is chytridiomycosis, caused by one of two chytridiomycete fungal pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal). Research over the last two decades has shown that susceptibility to this disease varies greatly with respect to a suite of host and pathogen factors such as phylogeny, geography (including abiotic factors), host community composition, and historical exposure to pathogens; yet, despite a growing body of research, a comprehensive understanding of global chytridiomycosis incidence remains elusive. In a large collaborative effort, Bd-Maps was launched in 2007 to increase multidisciplinary investigations and understanding using compiled global Bd occurrence data (Bsal was not discovered until 2013). As its database functions aged and became unsustainable, we sought to address critical needs utilizing new technologies to meet the challenges of aggregating data to facilitate research on both Bd and Bsal. Here, we introduce an advanced central online repository to archive, aggregate, and share Bd and Bsal data collected from around the world. The Amphibian Disease Portal (https://amphibiandisease.org) addresses several critical community needs while also helping to build basic biological knowledge of chytridiomycosis. This portal could be useful for other amphibian diseases and could also be replicated for uses with other wildlife diseases. We show how the Amphibian Disease Portal provides: (1) a new repository for the legacy Bd-Maps data; (2) a repository for sample-level data to archive datasets and host published data with permanent DOIs; (3) a flexible framework to adapt to advances in field, laboratory, and informatics technologies; and (4) a global aggregation of Bd and Bsal infection data to enable and accelerate research and conservation. The new framework for this project is built using biodiversity informatics best practices and metadata standards to ensure scientific reproducibility and linkages across other biological and biodiversity repositories.
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Affiliation(s)
- Michelle S Koo
- Museum of Vertebrate Zoology, University of California, Berkeley, Berkeley, CA, United States
| | - Vance T Vredenburg
- Museum of Vertebrate Zoology, University of California, Berkeley, Berkeley, CA, United States.,Department of Biology, San Francisco State University, San Francisco, CA, United States
| | - John B Deck
- Berkeley Natural History Museums, University of California, Berkeley, Berkeley, CA, United States
| | - Deanna H Olson
- US Department of Agriculture, Forest Service, Pacific Northwest Research Station, Corvallis, OR, United States
| | - Kathryn L Ronnenberg
- US Department of Agriculture, Forest Service, Pacific Northwest Research Station, Corvallis, OR, United States
| | - David B Wake
- Museum of Vertebrate Zoology, University of California, Berkeley, Berkeley, CA, United States
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16
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Becker MH, Brophy JAN, Barrett K, Bronikowski E, Evans M, Glassey E, Kaganer AW, Klocke B, Lassiter E, Meyer AJ, Muletz-Wolz CR, Fleischer RC, Voigt CA, Gratwicke B. Genetically modifying skin microbe to produce violacein and augmenting microbiome did not defend Panamanian golden frogs from disease. ISME COMMUNICATIONS 2021; 1:57. [PMID: 37938636 PMCID: PMC9723765 DOI: 10.1038/s43705-021-00044-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 08/02/2021] [Accepted: 08/09/2021] [Indexed: 04/21/2023]
Abstract
We designed two probiotic treatments to control chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) on infected Panamanian golden frogs (Atelopus zeteki), a species that is thought to be extinct in the wild due to Bd. The first approach disrupted the existing skin microbe community with antibiotics then exposed the frogs to a core golden frog skin microbe (Diaphorobacter sp.) that we genetically modified to produce high titers of violacein, a known antifungal compound. One day following probiotic treatment, the engineered Diaphorobacter and the violacein-producing pathway could be detected on the frogs but the treatment failed to improve frog survival when exposed to Bd. The second approach exposed frogs to the genetically modified bacterium mixed into a consortium with six other known anti-Bd bacteria isolated from captive A. zeteki, with no preliminary antibiotic treatment. The consortium treatment increased the frequency and abundance of three probiotic isolates (Janthinobacterium, Chryseobacterium, and Stenotrophomonas) and these persisted on the skin 4 weeks after probiotic treatment. There was a temporary increase in the frequency and abundance of three other probiotics isolates (Masillia, Serratia, and Pseudomonas) and the engineered Diaphorobacter isolate, but they subsequently disappeared from the skin. This treatment also failed to reduce frog mortality upon exposure.
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Affiliation(s)
- Matthew H Becker
- Smithsonian's National Zoo and Conservation Biology Institute, Center for Species Survival, Front Royal, VA, USA
- Liberty University Department of Biology and Chemistry, Lynchburg, VA, USA
| | - Jennifer A N Brophy
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | - Ed Bronikowski
- Smithsonian's National Zoo and Conservation Biology Institute Reptile Discovery Center, Washington, DC, USA
| | - Matthew Evans
- Smithsonian's National Zoo and Conservation Biology Institute Reptile Discovery Center, Washington, DC, USA
| | - Emerson Glassey
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Alyssa W Kaganer
- Smithsonian's National Zoo and Conservation Biology Institute, Center for Species Survival, Front Royal, VA, USA
| | - Blake Klocke
- Smithsonian's National Zoo and Conservation Biology Institute, Center for Species Survival, Front Royal, VA, USA
- Department of Environmental Science and Policy, George Mason University, Fairfax, VA, USA
| | - Elliot Lassiter
- Smithsonian's National Zoo and Conservation Biology Institute Reptile Discovery Center, Washington, DC, USA
| | - Adam J Meyer
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Carly R Muletz-Wolz
- Smithsonian's National Zoo and Conservation Biology Institute, Center for Conservation Genetics, Washington, DC, 20001, USA
| | - Robert C Fleischer
- Smithsonian's National Zoo and Conservation Biology Institute, Center for Conservation Genetics, Washington, DC, 20001, USA
| | - Christopher A Voigt
- Synthetic Biology Center, Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Brian Gratwicke
- Smithsonian's National Zoo and Conservation Biology Institute, Center for Species Survival, Front Royal, VA, USA.
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17
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Wang Y, Verbrugghe E, Meuris L, Chiers K, Kelly M, Strubbe D, Callewaert N, Pasmans F, Martel A. Epidermal galactose spurs chytrid virulence and predicts amphibian colonization. Nat Commun 2021; 12:5788. [PMID: 34608163 PMCID: PMC8490390 DOI: 10.1038/s41467-021-26127-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 09/09/2021] [Indexed: 02/08/2023] Open
Abstract
The chytrid fungal pathogens Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans cause the skin disease chytridiomycosis in amphibians, which is driving a substantial proportion of an entire vertebrate class to extinction. Mitigation of its impact is largely unsuccessful and requires a thorough understanding of the mechanisms underpinning the disease ecology. By identifying skin factors that mediate key events during the early interaction with B. salamandrivorans zoospores, we discovered a marker for host colonization. Amphibian skin associated beta-galactose mediated fungal chemotaxis and adhesion to the skin and initiated a virulent fungal response. Fungal colonization correlated with the skin glycosylation pattern, with cutaneous galactose content effectively predicting variation in host susceptibility to fungal colonization between amphibian species. Ontogenetic galactose patterns correlated with low level and asymptomatic infections in salamander larvae that were carried over through metamorphosis, resulting in juvenile mortality. Pronounced variation of galactose content within some, but not all species, may promote the selection for more colonization resistant host lineages, opening new avenues for disease mitigation.
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Affiliation(s)
- Yu Wang
- grid.5342.00000 0001 2069 7798Wildlife Health Ghent, Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Elin Verbrugghe
- grid.5342.00000 0001 2069 7798Wildlife Health Ghent, Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Leander Meuris
- grid.5342.00000 0001 2069 7798Center for Medical Biotechnology, Department of Biochemistry and Microbiology, VIB-Ghent University, Zwijnaarde, Belgium
| | - Koen Chiers
- grid.5342.00000 0001 2069 7798Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Moira Kelly
- grid.5342.00000 0001 2069 7798Wildlife Health Ghent, Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Diederik Strubbe
- grid.5342.00000 0001 2069 7798Terrestrial Ecology Unit, Department of Biology, Faculty of Sciences, Ghent University, Ghent, Belgium
| | - Nico Callewaert
- grid.5342.00000 0001 2069 7798Center for Medical Biotechnology, Department of Biochemistry and Microbiology, VIB-Ghent University, Zwijnaarde, Belgium
| | - Frank Pasmans
- grid.5342.00000 0001 2069 7798Wildlife Health Ghent, Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - An Martel
- grid.5342.00000 0001 2069 7798Wildlife Health Ghent, Department of Pathology, Bacteriology and Poultry Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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18
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Nava-González B, Suazo-Ortuño I, López PB, Maldonado-López Y, Lopez-Toledo L, Raggi L, Parra-Olea G, Alvarado-Díaz J, Gómez-Gil B. Inhibition of Batrachochytrium dendrobatidis Infection by Skin Bacterial Communities in Wild Amphibian Populations. MICROBIAL ECOLOGY 2021; 82:666-676. [PMID: 33598748 DOI: 10.1007/s00248-021-01706-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 01/26/2021] [Indexed: 06/12/2023]
Abstract
Skin-associated bacteria are known to inhibit infection by the fungal pathogen Batrachochytrium dendrobatidis (Bd) in amphibians. It has also been postulated that skin-associated bacterial community is related to Bd infection intensity. However, our understanding of host microbial dynamics and their importance in regulating Bd intensity is limited. We analyzed Bd infection and skin-associated bacteria from two amphibian species, the salamander Ambystoma rivulare and the frog Lithobates spectabilis that co-occurred in a tropical high-altitude site in central Mexico. Sixty-three percent of sampled salamander individuals and 80% of frog individuals tested positive for Bd. Overall, we registered 622 skin-associated bacterial genera, from which 73 are known to have Bd inhibitory effects. These inhibitory taxa represented a relative abundance of 50% in relation to total relative bacterial abundance. Our results indicated that, although sharing some bacterial taxa, bacterial community from the skin of both species was different in taxonomic composition and in relative abundance. Pseudomonas spp. and Stenotrophomonas spp. were among the five most abundant bacterial taxa of both species. Both bacterial taxa inhibit Bd infection. We detected that bacterial richness and relative abundance of inhibitory Bd bacteria were negatively related to intensity of Bd infection independent of species and seasons. Despite the high Bd prevalence in both host species, no dead or sick individuals were registered during field surveys. The relatively low levels of Bd load apparently do not compromise survival of host species. Therefore, our results suggested that individuals analyzed were able to survive and thrive under a dynamic relation with enzootic infections of Bd and their microbiota.
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Affiliation(s)
- Bisbrian Nava-González
- Instituto de Investigaciones sobre los Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Avenida Juanito Itzícuaro SN, Nueva Esperanza, 58330, Morelia, Michoacán, México
| | - Ireri Suazo-Ortuño
- Instituto de Investigaciones sobre los Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Avenida Juanito Itzícuaro SN, Nueva Esperanza, 58330, Morelia, Michoacán, México.
| | - Perla Bibian López
- Universidad Tecnológica de Morelia, Avenida Vicepresidente Pino Suárez 750, Cd. Industrial, 58200, Morelia, Michoacán, México
| | - Yurixhi Maldonado-López
- CONACyT-Instituto de Investigaciones sobre los Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Avenida Juanito Itzícuaro SN, Nueva Esperanza, 58330, Morelia, Michoacán, México
| | - Leonel Lopez-Toledo
- Instituto de Investigaciones sobre los Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Avenida Juanito Itzícuaro SN, Nueva Esperanza, 58330, Morelia, Michoacán, México
| | - Luciana Raggi
- CONACYT-Instituto de Investigaciones Agropecuarias y Forestales, Universidad Michoacana de San Nicolás de Hidalgo, Avenida Juanito Itzícuaro SN, Nueva Esperanza, 58330, Morelia, Michoacán, México
| | - Gabriela Parra-Olea
- Instituto de Biología, Universidad Nacional Autónoma de México, Cd de México, México
| | - Javier Alvarado-Díaz
- Instituto de Investigaciones sobre los Recursos Naturales, Universidad Michoacana de San Nicolás de Hidalgo, Avenida Juanito Itzícuaro SN, Nueva Esperanza, 58330, Morelia, Michoacán, México
| | - Bruno Gómez-Gil
- CIAD A.C., Mazatlán Unit for Aquaculture, AP 711, Mazatlán, 82000, Sinaloa, México
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19
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Deknock A, Pasmans F, van Leeuwenberg R, Van Praet S, Bruneel S, Lens L, Croubels S, Martel A, Goethals P. Alternative food sources interfere with removal of a fungal amphibian pathogen by zooplankton. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.14018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Arne Deknock
- Department of Animal Sciences and Aquatic Ecology Faculty of Bioscience Engineering Ghent University Ghent Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Poultry Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - Robby van Leeuwenberg
- Department of Pathology, Bacteriology and Poultry Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - Sarah Van Praet
- Department of Pathology, Bacteriology and Poultry Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - Stijn Bruneel
- Department of Animal Sciences and Aquatic Ecology Faculty of Bioscience Engineering Ghent University Ghent Belgium
| | - Luc Lens
- Department of Biology Faculty of Sciences Ghent University Ghent Belgium
| | - Siska Croubels
- Department of Pharmacology Toxicology and Biochemistry Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - An Martel
- Department of Pathology, Bacteriology and Poultry Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - Peter Goethals
- Department of Animal Sciences and Aquatic Ecology Faculty of Bioscience Engineering Ghent University Ghent Belgium
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20
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Waddle AW, Rivera R, Rice H, Keenan EC, Rezaei G, Levy JE, Vasquez YS, Sai M, Hill J, Zmuda A, Lambreghts Y, Jaeger JR. Amphibian resistance to chytridiomycosis increases following low‐virulence chytrid fungal infection or drug‐mediated clearance. J Appl Ecol 2021. [DOI: 10.1111/1365-2664.13974] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Anthony W. Waddle
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
- One Health Research Group Faculty of Veterinary and Agricultural Sciences University of Melbourne Werribee Vic. Australia
| | - Rebeca Rivera
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Hannah Rice
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Emma C. Keenan
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Ghazal Rezaei
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Joshua E. Levy
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Yesenia S. Vasquez
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Marlai Sai
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Jessica Hill
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Alexandra Zmuda
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
| | - Yorick Lambreghts
- School of Biological Sciences University of Tasmania Hobart TAS Australia
| | - Jef R. Jaeger
- School of Life Sciences University of Nevada, Las Vegas Las Vegas NV USA
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21
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Scheele BC, Hollanders M, Hoffmann EP, Newell DA, Lindenmayer DB, McFadden M, Gilbert DJ, Grogan LF. Conservation translocations for amphibian species threatened by chytrid fungus: A review, conceptual framework, and recommendations. CONSERVATION SCIENCE AND PRACTICE 2021. [DOI: 10.1111/csp2.524] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Ben C. Scheele
- Fenner School of Environment and Society Australian National University Canberra Australian Capital Territory Australia
| | - Matthijs Hollanders
- Faculty of Science and Engineering Southern Cross University Lismore New South Wales Australia
| | - Emily P. Hoffmann
- Fenner School of Environment and Society Australian National University Canberra Australian Capital Territory Australia
- School of Biological Sciences The University of Western Australia Crawley Western Australia Australia
| | - David A. Newell
- Faculty of Science and Engineering Southern Cross University Lismore New South Wales Australia
| | - David B. Lindenmayer
- Fenner School of Environment and Society Australian National University Canberra Australian Capital Territory Australia
| | - Michael McFadden
- Taronga Conservation Society Australia Mosman New South Wales Australia
| | - Deon J. Gilbert
- Wildlife Conservation and Science Zoos Victoria Parkville Victoria Australia
| | - Laura F. Grogan
- Centre for Planetary Health and Food Security, School of Environment and Science Griffith University Southport Queensland Australia
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22
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McGaugh SE, Lorenz AJ, Flagel LE. The utility of genomic prediction models in evolutionary genetics. Proc Biol Sci 2021; 288:20210693. [PMID: 34344180 PMCID: PMC8334854 DOI: 10.1098/rspb.2021.0693] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Accepted: 07/15/2021] [Indexed: 12/25/2022] Open
Abstract
Variation in complex traits is the result of contributions from many loci of small effect. Based on this principle, genomic prediction methods are used to make predictions of breeding value for an individual using genome-wide molecular markers. In breeding, genomic prediction models have been used in plant and animal breeding for almost two decades to increase rates of genetic improvement and reduce the length of artificial selection experiments. However, evolutionary genomics studies have been slow to incorporate this technique to select individuals for breeding in a conservation context or to learn more about the genetic architecture of traits, the genetic value of missing individuals or microevolution of breeding values. Here, we outline the utility of genomic prediction and provide an overview of the methodology. We highlight opportunities to apply genomic prediction in evolutionary genetics of wild populations and the best practices when using these methods on field-collected phenotypes.
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Affiliation(s)
- Suzanne E. McGaugh
- Ecology, Evolution, and Behavior, University of Minnesota, 140 Gortner Lab, 1479 Gortner Avenue, Saint Paul, MN 55108, USA
| | - Aaron J. Lorenz
- Agronomy and Plant Genetics, University of Minnesota, 411 Borlaug Hall, 1991 Upper Buford Circle, Saint Paul, MN 55108, USA
| | - Lex E. Flagel
- Plant and Microbial Biology, University of Minnesota, 140 Gortner Lab, 1479 Gortner Avenue, Saint Paul, MN 55108, USA
- Bayer Crop Science, 700 W Chesterfield Parkway, Chesterfield, MO 63017, USA
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23
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Fisher MC, Pasmans F, Martel A. Virulence and Pathogenicity of Chytrid Fungi Causing Amphibian Extinctions. Annu Rev Microbiol 2021; 75:673-693. [PMID: 34351790 DOI: 10.1146/annurev-micro-052621-124212] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Ancient enzootic associations between wildlife and their infections allow evolution to innovate mechanisms of pathogenicity that are counterbalanced by host responses. However, erosion of barriers to pathogen dispersal by globalization leads to the infection of hosts that have not evolved effective resistance and the emergence of highly virulent infections. Global amphibian declines driven by the rise of chytrid fungi and chytridiomycosis are emblematic of emerging infections. Here, we review how modern biological methods have been used to understand the adaptations and counteradaptations that these fungi and their amphibian hosts have evolved. We explore the interplay of biotic and abiotic factors that modify the virulence of these infections and dissect the complexity of this disease system. We highlight progress that has led to insights into how we might in the future lessen the impact of these emerging infections. Expected final online publication date for the Annual Review of Microbiology, Volume 75 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Matthew C Fisher
- MRC Centre for Global Infectious Disease Analysis, Department of Infectious Disease Epidemiology, Imperial School of Public Health, Imperial College London, London W2 1PG, United Kingdom;
| | - Frank Pasmans
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
| | - An Martel
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
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24
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Ujszegi J, Ludányi K, Móricz ÁM, Krüzselyi D, Drahos L, Drexler T, Németh MZ, Vörös J, Garner TWJ, Hettyey A. Exposure to Batrachochytrium dendrobatidis affects chemical defences in two anuran amphibians, Rana dalmatina and Bufo bufo. BMC Ecol Evol 2021; 21:135. [PMID: 34217227 PMCID: PMC8254444 DOI: 10.1186/s12862-021-01867-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 06/23/2021] [Indexed: 11/03/2022] Open
Abstract
Background Batrachochytrium dendrobatidis (Bd) is the causative agent of chytridiomycosis, one of the major causes of worldwide amphibian biodiversity loss. Many amphibians exhibit skin-based chemical defences, which may play an important role against invading pathogens, but whether the synthesis of these chemical compounds is enhanced or suppressed in the presence of pathogens is largely unknown. Here we investigated direct and indirect effects of larval exposure to the globally distributed and highly virulent Bd-GPL strain on skin secreted chemical defences and life history traits during early ontogeny of agile frogs (Rana dalmatina) and common toads (Bufo bufo). Results Exposure to Bd during the larval stage did not result in enhanced synthesis of the antimicrobial peptide Brevinin-1 Da in R. dalmatina tadpoles or in increased production of bufadienolides in B. bufo tadpoles. However, exposure to Bd during the larval stage had a carry-over effect reaching beyond metamorphosis: both R. dalmatina and B. bufo froglets contained smaller quantities of defensive chemicals than their Bd-naïve conspecifics in the control treatment. Prevalence of Bd and infection intensities were very low in both larvae and metamorphs of R. dalmatina, while in B. bufo we observed high Bd prevalence and infection intensities, especially in metamorphs. At the same time, we did not find a significant effect of Bd-exposure on body mass or development rate in larvae or metamorphs in either species. Conclusions The lack of detrimental effect of Bd-exposure on life history traits, even parallel with high infection intensities in the case of B. bufo individuals, is surprising and suggests high tolerance of local populations of these two species against Bd. However, the lowered quantity of defensive chemicals may compromise antimicrobial and antipredatory defences of froglets, which may ultimately contribute to population declines also in the absence of conspicuous mass-mortality events.
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Affiliation(s)
- János Ujszegi
- Lendület Evolutionary Ecology Research Group, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary.
| | - Krisztina Ludányi
- Department of Pharmaceutics, Faculty of Pharmacy, Semmelweis University, Hőgyes Endre utca 7, Budapest, 1092, Hungary
| | - Ágnes M Móricz
- Department of Pathophysiology, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary
| | - Dániel Krüzselyi
- Department of Pathophysiology, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary
| | - László Drahos
- MS Proteomics Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest, 1117, Hungary
| | - Tamás Drexler
- Lendület Evolutionary Ecology Research Group, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary.,Department of Ecology, Institute for Biology, University of Veterinary Medicine, Rottenbiller utca 50, Budapest, 1077, Hungary
| | - Márk Z Németh
- Department of Plant Pathology, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary
| | - Judit Vörös
- Department of Zoology, Hungarian Natural History Museum, Baross street 13, Budapest, 1088, Hungary
| | - Trenton W J Garner
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, UK.,Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
| | - Attila Hettyey
- Lendület Evolutionary Ecology Research Group, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary.,Department of Ecology, Institute for Biology, University of Veterinary Medicine, Rottenbiller utca 50, Budapest, 1077, Hungary
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25
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Bozzuto C, Canessa S, Koella JC. Exploring artificial habitat fragmentation to control invasion by infectious wildlife diseases. Theor Popul Biol 2021; 141:14-23. [PMID: 34139201 DOI: 10.1016/j.tpb.2021.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 05/26/2021] [Accepted: 06/01/2021] [Indexed: 10/21/2022]
Abstract
One way to reduce the impacts of invading wildlife diseases is setting up fences that would reduce the spread of pathogens by limiting connectivity, similarly to exclusion fences that are commonly used to conserve threatened species against invasive predators. One of the problems with fences is that, while they may have the short-term benefit of impeding the spread of disease, this benefit may be offset by potential long-term ecological costs of fragmentation by fencing. However, managers facing situations where a pathogen has been detected near the habitat of a (highly) vulnerable species may be willing to explore such a trade-off. To aid such exploration quantitatively, we present a series of models trading off the benefits of fragmentation (potential reduction of disease impacts on susceptible individuals) against its costs (both financial and ecological, i.e. reduced viability in the patches created by fragmentation), and exploring the effects of fragmentation on non-target species richness. For all model variants we derive the optimal number of artificial patches. We show that pre-emptive disease fences may have benefits when the risk of disease exceeds the impacts of fragmentation, when fence failure rates are lower than a specific threshold, and when sufficient resources are available to implement optimal solutions. A useful step to initiate planning is to obtain information about the expected number of initial infection events and on the host's extinction threshold with respect to the focal habitat and management duration. Our approach can assist managers to identify whether the trade-offs support the decision to fence and how intensive fragmentation should be.
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Affiliation(s)
- Claudio Bozzuto
- Wildlife Analysis GmbH, Oetlisbergstrasse 38, 8053 Zurich, Switzerland.
| | - Stefano Canessa
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
| | - Jacob C Koella
- Laboratory of ecology and epidemiology of parasites, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
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26
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Lammens L, Martel A, Pasmans F. Application of Disinfectants for Environmental Control of a Lethal Amphibian Pathogen. J Fungi (Basel) 2021; 7:jof7060406. [PMID: 34064294 PMCID: PMC8224365 DOI: 10.3390/jof7060406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 11/16/2022] Open
Abstract
Chytridiomycosis is an emerging infectious disease threatening amphibian populations worldwide. While environmental disinfection is important in mitigating the disease, successful elimination of Batrachochytrium dendrobatidis (Bd) without excessively harming ecosystems is challenging. We selected peracetic acid (PAA) as the most potent of six commercially available products regarding their ability to inhibit growth of a highly virulent Bd strain. PAA killed Bd after 5 min of exposure to approximately 94.7 mg/L. We examined the toxicity of PAA against three invertebrate species and Discoglossus pictus tadpoles. 93% of invertebrates, but none of the tadpoles survived 5 min of exposure to 94.7 mg/L. Tadpoles showed no adverse effects after 5 min exposure to concentrations of approximately 37.9 mg/L or lower. Addition of PAA to aquatic microcosms decreased pH, while dissolved oxygen (DO) initially increased. Degradation of PAA reversed the pH drop, but caused a massive drop in DO, which could be remedied by aeration. As proof of concept, microcosms that were aerated and treated with 94.7 mg/L PAA sustained survival of tadpoles starting 48 h after treatment. Disinfecting aquatic environments using PAA could contribute to mitigating chytridiomycosis, while preserving at least some invertebrate diversity, but requires temporary removal of resident amphibians.
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27
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Bielby J, Price SJ, Monsalve-CarcaÑo C, Bosch J. Host contribution to parasite persistence is consistent between parasites and over time, but varies spatially. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e02256. [PMID: 33164249 DOI: 10.1002/eap.2256] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 06/11/2020] [Accepted: 08/16/2020] [Indexed: 06/11/2023]
Abstract
Most parasites and pathogens infect multiple hosts, but a great deal of variation exists in the role of those hosts in persistence of infection. Understanding which hosts are most important in maintaining parasites can provide a clearer target for infection control. Recently developed empirical and theoretical approaches provide a way to quantify the relative contribution of hosts within a community and place them in a multi-host framework to better direct control efforts. Amphibians provide a framework for better understanding multi-host-multi-parasite dynamics. Two well-studied amphibian parasites, Batrachochytrium dendrobatidis (Bd) and Ranavirus, infect multiple host species and exhibit a great deal of heterogeneity in how they affect hosts. We used these two parasites and a community of five amphibian species to investigate the relative importance of hosts in parasite persistence, and how any patterns varied spatially and temporally. At two sites (Lake Ercina and Lake Lloroza in the Picos de Europa National Park, Spain) we collected data on the prevalence and shedding rate of parasite infection for both Bd and Ranavirus, and the abundance of each species' life stages. We used these data to parameterize a recently developed modeling framework, which was used to quantify the relative contribution of each host to the community reproductive number, R0 . By comparing each host-category over time and between sites we were able to identify consistencies in which host was responsible for the maintenance of these two parasites. Within a site one species consistently contributed the most to the persistence of both parasites. This consistency did not transfer between sites, the maintenance host species being different for each. At one site (Ercina), life stages of the common midwife toad, Alytes obstetricans, acted as the maintenance host for both Bd and Ranavirus. In contrast, at the second site, Lloroza, the alpine newt, Ichthyosaura alpestris, fulfilled that role. A single host species was responsible for infection persistence of both parasites at each lake. Attempts to control the infection levels and impacts of multiple parasites can benefit from a community epidemiology approach, and provide clarity on which hosts are the foci of mitigation efforts. However, at a small spatial scale, the target host may vary according to the physical qualities of those sites and the demographics of the host community.
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Affiliation(s)
- Jon Bielby
- School of Natural Sciences and Psychology, Liverpool John Moores University, James Parsons Building, Byrom Street, Liverpool, L3 3AF, United Kingdom
| | - Stephen J Price
- UCL Genetics Institute, Darwin Building, Gower Street, London, WC1E 6BT, United Kingdom
- Institute of Zoology, Zoological Society of London, Regents Park, London, NW1 4RY, United Kingdom
| | | | - Jaime Bosch
- Museo Nacional de Ciencias Naturales, CSIC, José Gutiérrez Abascal 2, Madrid, 28006, Spain
- Research Unit of Biodiversity (CSIC, UO, PA), Oviedo University-Campus Mieres, Mieres, Spain
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28
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Valenzuela-Sánchez A, Wilber MQ, Canessa S, Bacigalupe LD, Muths E, Schmidt BR, Cunningham AA, Ozgul A, Johnson PTJ, Cayuela H. Why disease ecology needs life-history theory: a host perspective. Ecol Lett 2021; 24:876-890. [PMID: 33492776 DOI: 10.1111/ele.13681] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 12/16/2020] [Accepted: 12/18/2020] [Indexed: 12/16/2022]
Abstract
When facing an emerging infectious disease of conservation concern, we often have little information on the nature of the host-parasite interaction to inform management decisions. However, it is becoming increasingly clear that the life-history strategies of host species can be predictive of individual- and population-level responses to infectious disease, even without detailed knowledge on the specifics of the host-parasite interaction. Here, we argue that a deeper integration of life-history theory into disease ecology is timely and necessary to improve our capacity to understand, predict and mitigate the impact of endemic and emerging infectious diseases in wild populations. Using wild vertebrates as an example, we show that host life-history characteristics influence host responses to parasitism at different levels of organisation, from individuals to communities. We also highlight knowledge gaps and future directions for the study of life-history and host responses to parasitism. We conclude by illustrating how this theoretical insight can inform the monitoring and control of infectious diseases in wildlife.
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Affiliation(s)
- Andrés Valenzuela-Sánchez
- Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile.,ONG Ranita de Darwin, Valdivia and Santiago, Chile.,Centro de Investigación para la Sustentabilidad, Universidad Andrés Bello, Santiago, Chile
| | - Mark Q Wilber
- Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA, 93106, USA.,Center for Wildlife Health, Department of Forestry, Wildlife and Fisheries, University of Tennessee Institute of Agriculture, Knoxville, TN, 37996, USA
| | - Stefano Canessa
- Wildlife Health Ghent, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Leonardo D Bacigalupe
- Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Valdivia, Chile
| | - Erin Muths
- U.S. Geological Survey, 2150 Centre Avenue Bldg C, Fort Collins, Colorado, 80526, USA
| | - Benedikt R Schmidt
- Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland.,Info Fauna Karch, UniMail, Bâtiment G, Bellevaux 51, 2000, Neuchâtel, Switzerland
| | - Andrew A Cunningham
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, UK
| | - Arpat Ozgul
- Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - Pieter T J Johnson
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, 80309, USA
| | - Hugo Cayuela
- IBIS, Department of Biology, University Laval, Pavillon Charles-Eugène-Marchand, Avenue de la Médecine, Quebec City, Canada.,Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland
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29
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Continued preference for suboptimal habitat reduces bat survival with white-nose syndrome. Nat Commun 2021; 12:166. [PMID: 33420005 PMCID: PMC7794521 DOI: 10.1038/s41467-020-20416-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 11/23/2020] [Indexed: 12/27/2022] Open
Abstract
Habitat alteration can influence suitability, creating ecological traps where habitat preference and fitness are mismatched. Despite their importance, ecological traps are notoriously difficult to identify and their impact on host–pathogen dynamics remains largely unexplored. Here we assess individual bat survival and habitat preferences in the midwestern United States before, during, and after the invasion of the fungal pathogen that causes white-nose syndrome. Despite strong selection pressures, most hosts continued to select habitats where disease severity was highest and survival was lowest, causing continued population declines. However, some individuals used refugia where survival was higher. Over time, a higher proportion of the total population used refugia than before pathogen arrival. Our results demonstrate that host preferences for habitats with high disease-induced mortality can create ecological traps that threaten populations, even in the presence of accessible refugia. Temperature-dependent host–pathogen interactions may lead species to shift their thermal preferences under pathogen pressure. However, here the authors show that bats have not altered their microclimate preferences due to temperature-mediated mortality from white-nose syndrome, finding instead a sustained preference for warmer sites with high mortality.
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30
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Burns TJ, Scheele BC, Brannelly LA, Clemann N, Gilbert D, Driscoll DA. Indirect terrestrial transmission of amphibian chytrid fungus from reservoir to susceptible host species leads to fatal chytridiomycosis. Anim Conserv 2020. [DOI: 10.1111/acv.12665] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Thomas J. Burns
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University (Burwood Campus) Geelong Vic. Australia
| | - Ben C. Scheele
- Fenner School of Environment and Society Australian National University Canberra ACT Australia
| | - Laura A. Brannelly
- Melbourne Veterinary School Faculty of Veterinary and Agricultural Sciences University of Melbourne Werribee Vic. Australia
| | - Nick Clemann
- Department of Environment, Land, Water and Planning Arthur Rylah Institute for Environmental Research Heidelberg Vic. Australia
| | - Deon Gilbert
- Wildlife Conservation and Science. Zoos Victoria Parkville Vic. Australia
| | - Don A. Driscoll
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University (Burwood Campus) Geelong Vic. Australia
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31
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Bosch J, Carrascal LM, Manica A, Garner TWJ. Significant reductions of host abundance weakly impact infection intensity of Batrachochytrium dendrobatidis. PLoS One 2020; 15:e0242913. [PMID: 33253322 PMCID: PMC7703926 DOI: 10.1371/journal.pone.0242913] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 11/10/2020] [Indexed: 11/19/2022] Open
Abstract
Infectious diseases are considered major threats to biodiversity, however strategies to mitigate their impacts in the natural world are scarce and largely unsuccessful. Chytridiomycosis is responsible for the decline of hundreds of amphibian species worldwide, but an effective disease management strategy that could be applied across natural habitats is still lacking. In general amphibian larvae can be easily captured, offering opportunities to ascertain the impact of altering the abundance of hosts, considered to be a key parameter affecting the severity of the disease. Here, we report the results of two experiments to investigate how altering host abundance affects infection intensity in amphibian populations of a montane area of Central Spain suffering from lethal amphibian chytridiomycosis. Our laboratory-based experiment supported the conclusion that varying density had a significant effect on infection intensity when salamander larvae were housed at low densities. Our field experiment showed that reducing the abundance of salamander larvae in the field also had a significant, but weak, impact on infection the following year, but only when removals were extreme. While this suggests adjusting host abundance as a mitigation strategy to reduce infection intensity could be useful, our evidence suggests only heavy culling efforts will succeed, which may run contrary to objectives for conservation.
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Affiliation(s)
- Jaime Bosch
- Research Unit of Biodiversity (CSIC, UO, PA), Gonzalo Gutiérrez Quirós s/n, Oviedo University - Campus Mieres, Edificio de Investigación, Mieres, Spain
- Centro de Investigación, Seguimiento y Evaluación, Rascafría, Spain
- Museo Nacional de Ciencias Naturales-CSIC, Madrid, Spain
| | | | - Andrea Manica
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
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32
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Bozzuto C, Schmidt BR, Canessa S. Active responses to outbreaks of infectious wildlife diseases: objectives, strategies and constraints determine feasibility and success. Proc Biol Sci 2020; 287:20202475. [PMID: 33234080 DOI: 10.1098/rspb.2020.2475] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Emerging wildlife diseases are taking a heavy toll on animal and plant species worldwide. Mitigation, particularly in the initial epidemic phase, is hindered by uncertainty about the epidemiology and management of emerging diseases, but also by vague or poorly defined objectives. Here, we use a quantitative analysis to assess how the decision context of mitigation objectives, available strategies and practical constraints influences the decision of whether and how to respond to epidemics in wildlife. To illustrate our approach, we parametrized the model for European fire salamanders affected by Batrachochytrium salamandrivorans, and explored different combinations of conservation, containment and budgetary objectives. We found that in approximately half of those scenarios, host removal strategies perform equal to or worse than no management at all during a local outbreak, particularly where removal cannot exclusively target infected individuals. Moreover, the window for intervention shrinks rapidly if an outbreak is detected late or if a response is delayed. Clearly defining the decision context is, therefore, vital to plan meaningful responses to novel outbreaks. Explicitly stating objectives, strategies and constraints, if possible before an outbreak occurs, avoids wasting precious resources and creating false expectations about what can and cannot be achieved during the epidemic phase.
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Affiliation(s)
- Claudio Bozzuto
- Wildlife Analysis GmbH, Oetlisbergstrasse 38, 8053 Zurich, Switzerland
| | - Benedikt R Schmidt
- Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.,info fauna karch, UniMail, Bâtiment G, Bellevaux 51, 2000 Neuchâtel, Switzerland
| | - Stefano Canessa
- Wildlife Health Ghent, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
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33
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Brannelly LA, McCallum HI, Grogan LF, Briggs CJ, Ribas MP, Hollanders M, Sasso T, Familiar López M, Newell DA, Kilpatrick AM. Mechanisms underlying host persistence following amphibian disease emergence determine appropriate management strategies. Ecol Lett 2020; 24:130-148. [PMID: 33067922 DOI: 10.1111/ele.13621] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 06/18/2020] [Accepted: 09/08/2020] [Indexed: 12/19/2022]
Abstract
Emerging infectious diseases have caused many species declines, changes in communities and even extinctions. There are also many species that persist following devastating declines due to disease. The broad mechanisms that enable host persistence following declines include evolution of resistance or tolerance, changes in immunity and behaviour, compensatory recruitment, pathogen attenuation, environmental refugia, density-dependent transmission and changes in community composition. Here we examine the case of chytridiomycosis, the most important wildlife disease of the past century. We review the full breadth of mechanisms allowing host persistence, and synthesise research on host, pathogen, environmental and community factors driving persistence following chytridiomycosis-related declines and overview the current evidence and the information required to support each mechanism. We found that for most species the mechanisms facilitating persistence have not been identified. We illustrate how the mechanisms that drive long-term host population dynamics determine the most effective conservation management strategies. Therefore, understanding mechanisms of host persistence is important because many species continue to be threatened by disease, some of which will require intervention. The conceptual framework we describe is broadly applicable to other novel disease systems.
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Affiliation(s)
- Laura A Brannelly
- Veterinary BioSciences, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Werribee, Vic, 3030, Australia
| | - Hamish I McCallum
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Nathan, Qld., 4111, Australia
| | - Laura F Grogan
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Nathan, Qld., 4111, Australia.,Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Cheryl J Briggs
- Ecology, Evolution and Marine Biology, University of California Santa Barbara, Santa Barbara, CA, 93106, USA
| | - Maria P Ribas
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, 2480, Australia.,Wildlife Conservation Medicine Research Group, Departament de Medicina i Cirurgia Animals, Universitat Autònoma de Barcelona, Bellaterra, 08193, Spain
| | - Matthijs Hollanders
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Thais Sasso
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Nathan, Qld., 4111, Australia
| | - Mariel Familiar López
- School of Environment and Sciences, Griffith University, Gold Coast, Qld., 4215, Australia
| | - David A Newell
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW, 2480, Australia
| | - Auston M Kilpatrick
- Department of Ecology and Evolutionary Biology, University of California Santa Cruz, Santa Cruz, CA, 95064, USA
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34
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Rodriguez KM, Voyles J. The amphibian complement system and chytridiomycosis. JOURNAL OF EXPERIMENTAL ZOOLOGY PART 2020; 333:706-719. [PMID: 33052039 PMCID: PMC7821119 DOI: 10.1002/jez.2419] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 08/26/2020] [Accepted: 09/24/2020] [Indexed: 12/26/2022]
Abstract
Understanding host immune function and ecoimmunology is increasingly important at a time when emerging infectious diseases (EIDs) threaten wildlife. One EID that has emerged and spread widely in recent years is chytridiomycosis, caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd), which is implicated unprecedented amphibian declines around the world. The impacts of Bd have been severe for many amphibian species, but some populations have exhibited signs of persistence, and even recovery, in some regions. Many mechanisms may underpin this pattern and amphibian immune responses are likely one key component. Although we have made great strides in understanding amphibian immunity, the complement system remains poorly understood. The complement system is a nonspecific, innate immune defense that is known to enhance other immune responses. Complement activation can occur by three different biochemical pathways and result in protective mechanisms, such as inflammation, opsonization, and pathogen lysis, thereby providing protection to the host. We currently lack an understanding of complement pathway activation for chytridiomycosis, but several studies have suggested that it may be a key part of an early and robust immune response that confers host resistance. Here, we review the available research on the complement system in general as well as amphibian complement responses to Bd infection. Additionally, we propose future research directions that will increase our understanding of the amphibian complement system and other immune responses to Bd. Finally, we suggest how a deeper understanding of amphibian immunity could enhance the conservation and management of amphibian species that are threatened by chytridiomycosis.
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Affiliation(s)
| | - Jamie Voyles
- Department of Biology, University of Nevada-Reno, Reno, Nevada, USA
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35
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Rothstein AP, Knapp RA, Bradburd GS, Boiano DM, Briggs CJ, Rosenblum EB. Stepping into the past to conserve the future: Archived skin swabs from extant and extirpated populations inform genetic management of an endangered amphibian. Mol Ecol 2020; 29:2598-2611. [PMID: 32573039 DOI: 10.1111/mec.15515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 05/21/2020] [Accepted: 06/05/2020] [Indexed: 12/20/2022]
Abstract
Moving animals on a landscape through translocations and reintroductions is an important management tool used in the recovery of endangered species, particularly for the maintenance of population genetic diversity and structure. Management of imperiled amphibian species rely heavily on translocations and reintroductions, especially for species that have been brought to the brink of extinction by habitat loss, introduced species, and disease. One striking example of amphibian declines and associated management efforts is in California's Sequoia and Kings Canyon National Parks with the mountain yellow-legged frog species complex (Rana sierrae/muscosa). Mountain yellow-legged frogs have been extirpated from more than 93% of their historic range, and limited knowledge of their population genetics has made long-term conservation planning difficult. To address this, we used 598 archived skin swabs from both extant and extirpated populations across 48 lake basins to generate a robust Illumina-based nuclear amplicon data set. We found that samples grouped into three main genetic clusters, concordant with watershed boundaries. We also found evidence for historical gene flow across watershed boundaries with a north-to-south axis of migration. Finally, our results indicate that genetic diversity is not significantly different between populations with different disease histories. Our study offers specific management recommendations for imperiled mountain yellow-legged frogs and, more broadly, provides a population genetic framework for leveraging minimally invasive samples for the conservation of threatened species.
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Affiliation(s)
- Andrew P Rothstein
- Department of Environmental Science, Policy, and Management, University of California Berkeley, Berkeley, CA, USA.,Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, USA
| | - Roland A Knapp
- Sierra Nevada Aquatic Research Laboratory, University of California, Mammoth Lakes, CA, USA
| | - Gideon S Bradburd
- Department of Integrative Biology, Michigan State University, East Lansing, MI, USA
| | - Daniel M Boiano
- Sequoia and Kings Canyon National Parks, Three Rivers, CA, USA
| | - Cheryl J Briggs
- Department of Ecology, Evolution, and Marine Biology, University of California, CA, USA
| | - Erica Bree Rosenblum
- Department of Environmental Science, Policy, and Management, University of California Berkeley, Berkeley, CA, USA.,Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA, USA
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36
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Ford J, Hunt DA, Haines GE, Lewis M, Lewis Y, Green DM. Adrift on a Sea of Troubles: Can Amphibians Survive in a Human-Dominated World?1. HERPETOLOGICA 2020. [DOI: 10.1655/0018-0831-76.2.251] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Jessica Ford
- Redpath Museum, McGill University, Montreal, QC H3A 0C4, Canada
| | | | - Grant E. Haines
- Redpath Museum, McGill University, Montreal, QC H3A 0C4, Canada
| | - Micaela Lewis
- Redpath Museum, McGill University, Montreal, QC H3A 0C4, Canada
| | - Yael Lewis
- Redpath Museum, McGill University, Montreal, QC H3A 0C4, Canada
| | - David M. Green
- Redpath Museum, McGill University, Montreal, QC H3A 0C4, Canada
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37
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Muths E, Hossack B, Campbell Grant E, Pilliod D, Mosher B. Effects of Snowpack, Temperature, and Disease on Demography in a Wild Population of Amphibians. HERPETOLOGICA 2020. [DOI: 10.1655/0018-0831-76.2.132] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- E. Muths
- US Geological Survey, Fort Collins Science Center, 2150 Centre Avenue, Building C, Fort Collins, CO 80526, USA
| | - B.R. Hossack
- US Geological Survey, Northern Rocky Mountain Science Center, Wildlife Biology Program, University of Montana, Missoula, MT 59812, USA
| | - E.H. Campbell Grant
- US Geological Survey, Patuxent Wildlife Research Center, SO Conte Anadromous Fish Laboratory, One Migratory Way, Turners Falls, MA 01376, USA
| | - D.S. Pilliod
- US Geological Survey, Forest and Rangeland Ecosystem Science Center, 970 Lusk Street, Boise, ID 83706, USA
| | - B.A. Mosher
- University of Vermont, Rubenstein School of Environment and Natural Resources, Aiken Center, 81 Carrigan Drive, Burlington, VT 05405, USA
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38
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Robinson KA, Pereira KE, Bletz MC, Carter ED, Gray MJ, Piovia-Scott J, Romansic JM, Woodhams DC, Fritz-Laylin L. Isolation and maintenance of Batrachochytrium salamandrivorans cultures. DISEASES OF AQUATIC ORGANISMS 2020; 140:1-11. [PMID: 32618283 DOI: 10.3354/dao03488] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Discovered in 2013, the chytrid fungus Batrachochytrium salamandrivorans (Bsal) is an emerging amphibian pathogen that causes ulcerative skin lesions and multifocal erosion. A closely related pathogen, B. dendrobatidis (Bd), has devastated amphibian populations worldwide, suggesting that Bsal poses a significant threat to global salamander biodiversity. To expedite research into this emerging threat, we seek to standardize protocols across the field so that results of laboratory studies are reproducible and comparable. We have collated data and experience from multiple labs to standardize culturing practices of Bsal. Here we outline common culture practices including a medium for standardized Bsal growth, standard culturing protocols, and a method for isolating Bsal from infected tissue.
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Affiliation(s)
- Kristyn A Robinson
- Department of Biology, University of Massachusetts, Amherst, MA 01003, USA
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39
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Fisher MC, Gurr SJ, Cuomo CA, Blehert DS, Jin H, Stukenbrock EH, Stajich JE, Kahmann R, Boone C, Denning DW, Gow NAR, Klein BS, Kronstad JW, Sheppard DC, Taylor JW, Wright GD, Heitman J, Casadevall A, Cowen LE. Threats Posed by the Fungal Kingdom to Humans, Wildlife, and Agriculture. mBio 2020; 11:e00449-20. [PMID: 32371596 PMCID: PMC7403777 DOI: 10.1128/mbio.00449-20] [Citation(s) in RCA: 202] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The fungal kingdom includes at least 6 million eukaryotic species and is remarkable with respect to its profound impact on global health, biodiversity, ecology, agriculture, manufacturing, and biomedical research. Approximately 625 fungal species have been reported to infect vertebrates, 200 of which can be human associated, either as commensals and members of our microbiome or as pathogens that cause infectious diseases. These organisms pose a growing threat to human health with the global increase in the incidence of invasive fungal infections, prevalence of fungal allergy, and the evolution of fungal pathogens resistant to some or all current classes of antifungals. More broadly, there has been an unprecedented and worldwide emergence of fungal pathogens affecting animal and plant biodiversity. Approximately 8,000 species of fungi and Oomycetes are associated with plant disease. Indeed, across agriculture, such fungal diseases of plants include new devastating epidemics of trees and jeopardize food security worldwide by causing epidemics in staple and commodity crops that feed billions. Further, ingestion of mycotoxins contributes to ill health and causes cancer. Coordinated international research efforts, enhanced technology translation, and greater policy outreach by scientists are needed to more fully understand the biology and drivers that underlie the emergence of fungal diseases and to mitigate against their impacts. Here, we focus on poignant examples of emerging fungal threats in each of three areas: human health, wildlife biodiversity, and food security.
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Affiliation(s)
- Matthew C Fisher
- MRC Centre for Global Infectious Disease Analysis, Imperial College, London, United Kingdom
| | - Sarah J Gurr
- Department of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Christina A Cuomo
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, USA
| | - David S Blehert
- U.S. Geological Survey, National Wildlife Health Center, Madison, Wisconsin, USA
| | - Hailing Jin
- Department of Microbiology and Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California-Riverside, Riverside, California, USA
| | - Eva H Stukenbrock
- Max Planck Fellow Group Environmental Genomics, Max Planck Institute for Evolutionary Biology, Plön, Germany
- Environmental Genomics, Christian-Albrechts University, Kiel, Germany
| | - Jason E Stajich
- Department of Microbiology and Plant Pathology, Center for Plant Cell Biology, Institute for Integrative Genome Biology, University of California-Riverside, Riverside, California, USA
| | - Regine Kahmann
- Max Planck Institute for Terrestrial Microbiology, Department of Organismic Interactions, Marburg, Germany
| | - Charles Boone
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- The Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
- RIKEN Center for Sustainable Resource Science, Wako, Saitama, Japan
| | - David W Denning
- The National Aspergillosis Centre, Wythenshawe Hospital, The University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Neil A R Gow
- Department of Biosciences, University of Exeter, Exeter, United Kingdom
| | - Bruce S Klein
- Department of Pediatrics, Department of Internal Medicine, and Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - James W Kronstad
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia, Canada
| | - Donald C Sheppard
- McGill Interdisciplinary Initiative in Infection and Immunology, Departments of Medicine, Microbiology & Immunology, McGill University, Montreal, Canada
| | - John W Taylor
- University of California-Berkeley, Department of Plant and Microbial Biology, Berkeley, California, USA
| | - Gerard D Wright
- M.G. DeGroote Institute for Infectious Disease Research, Department of Biochemistry and Biomedical Sciences, DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Joseph Heitman
- Department of Molecular Genetics and Microbiology, Medicine, and Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina, USA
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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40
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Weldon C, Channing A, Misinzo G, Cunningham AA. Disease driven extinction in the wild of the Kihansi spray toad, Nectophrynoides asperginis. AFR J HERPETOL 2020. [DOI: 10.1080/21564574.2020.1752313] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Ché Weldon
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Alan Channing
- Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - Gerald Misinzo
- SACIDS Africa Centre of Excellence for Infectious Diseases of Humans and Animals in Eastern and Southern Africa, Sokoine University of Agriculture, Morogoro, Tanzania
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41
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Lindauer AL, Maier PA, Voyles J. Daily fluctuating temperatures decrease growth and reproduction rate of a lethal amphibian fungal pathogen in culture. BMC Ecol 2020; 20:18. [PMID: 32245440 PMCID: PMC7118903 DOI: 10.1186/s12898-020-00286-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2019] [Accepted: 03/26/2020] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Emerging infectious diseases (EIDs) are contributing to species die-offs worldwide. We can better understand EIDs by using ecological approaches to study pathogen biology. For example, pathogens are exposed to variable temperatures across daily, seasonal, and annual scales. Exposure to temperature fluctuations may reduce pathogen growth and reproduction, which could affect pathogen virulence, transmission, and environmental persistence with implications for disease. We examined the effect of a variable thermal environment on reproductive life history traits of the fungal pathogen Batrachochytrium dendrobatidis (Bd). Bd causes chytridiomycosis, an emerging infectious disease of amphibians. As a pathogen of ectothermic hosts, Bd can be exposed to large temperature fluctuations in nature. To determine the effect of fluctuating temperatures on Bd growth and reproduction, we collected temperature data from breeding pools of the Yosemite toad (Anaxyrus canorus), a federally threatened species that is susceptible to chytridiomycosis. We cultured Bd under a daily fluctuating temperature regime that simulated Yosemite toad breeding pool temperatures and measured Bd growth, reproduction, fecundity, and viability. RESULTS We observed decreased Bd growth and reproduction in a diurnally fluctuating thermal environment as compared to cultures grown at constant temperatures within the optimal Bd thermal range. We also found that Bd exhibits temperature-induced trade-offs under constant low and constant high temperature conditions. CONCLUSIONS Our results provide novel insights on variable responses of Bd to dynamic thermal conditions and highlight the importance of incorporating realistic temperature fluctuations into investigations of pathogen ecology and EIDs.
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Affiliation(s)
- Alexa L Lindauer
- Department of Biology, University of Nevada Reno, 1664 N. Virginia Street, Reno, NV, 89557, USA.
| | - Paul A Maier
- Department of Biology, San Diego State University, 5500 Campanile Drive, San Diego, CA, 92182, USA.,FamilyTreeDNA, Gene by Gene, 1445 N Loop W, Houston, TX, 77008, USA
| | - Jamie Voyles
- Department of Biology, University of Nevada Reno, 1664 N. Virginia Street, Reno, NV, 89557, USA
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42
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Abstract
Discovering that chytrid fungi cause chytridiomycosis in amphibians represented a paradigm shift in our understanding of how emerging infectious diseases contribute to global patterns of biodiversity loss. In this Review we describe how the use of multidisciplinary biological approaches has been essential to pinpointing the origins of amphibian-parasitizing chytrid fungi, including Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans, as well as to timing their emergence, tracking their cycles of expansion and identifying the core mechanisms that underpin their pathogenicity. We discuss the development of the experimental methods and bioinformatics toolkits that have provided a fuller understanding of batrachochytrid biology and informed policy and control measures.
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43
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Crockett JG, Bailey LL, Muths E. Highly variable rates of survival to metamorphosis in wild boreal toads (
Anaxyrus boreas boreas
). POPUL ECOL 2020. [DOI: 10.1002/1438-390x.12044] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- John G. Crockett
- Department of Fish, Wildlife, and Conservation Biology Colorado State University Fort Collins Colorado
| | - Larissa L. Bailey
- Department of Fish, Wildlife, and Conservation Biology Colorado State University Fort Collins Colorado
| | - Erin Muths
- United States Geological Survey Fort Collins Science Center Fort Collins Colorado
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44
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Martel A, Vila‐Escale M, Fernández‐Giberteau D, Martinez‐Silvestre A, Canessa S, Van Praet S, Pannon P, Chiers K, Ferran A, Kelly M, Picart M, Piulats D, Li Z, Pagone V, Pérez‐Sorribes L, Molina C, Tarragó‐Guarro A, Velarde‐Nieto R, Carbonell F, Obon E, Martínez‐Martínez D, Guinart D, Casanovas R, Carranza S, Pasmans F. Integral chain management of wildlife diseases. Conserv Lett 2020. [DOI: 10.1111/conl.12707] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Affiliation(s)
- An Martel
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Mireia Vila‐Escale
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Daniel Fernández‐Giberteau
- Grup de Recerca de l'Escola de la Natura de Parets del Vallès – Ajuntament de Parets del Vallès Parets del Vallès Spain
| | | | - Stefano Canessa
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Sarah Van Praet
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Pep Pannon
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Koen Chiers
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Albert Ferran
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Moira Kelly
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Mariona Picart
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Dolors Piulats
- Institute of Evolutionary Biology (CSIC‐UPF) Barcelona Spain
| | - Zhimin Li
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
| | - Viviana Pagone
- Institute of Evolutionary Biology (CSIC‐UPF) Barcelona Spain
| | - Laia Pérez‐Sorribes
- Grup de Recerca de l'Escola de la Natura de Parets del Vallès – Ajuntament de Parets del Vallès Parets del Vallès Spain
| | - Carolina Molina
- Grup de Recerca de l'Escola de la Natura de Parets del Vallès – Ajuntament de Parets del Vallès Parets del Vallès Spain
| | - Aïda Tarragó‐Guarro
- Departament de Territori i SostenibilitatGeneralitat de Catalunya Barcelona Spain
| | - Roser Velarde‐Nieto
- Departament de Medicina i Cirurgia AnimalsFacultat de VeterinàriaUniversitat Autònoma de Barcelona Bellaterra Spain
| | - Francesc Carbonell
- Àrea de Gestió Ambiental Servei de Fauna i Flora (Centre de Fauna de Torreferrussa) Santa Perpètua de Mogoda Spain
| | - Elena Obon
- Àrea de Gestió Ambiental Servei de Fauna i Flora (Centre de Fauna de Torreferrussa) Santa Perpètua de Mogoda Spain
| | | | - Daniel Guinart
- Oficina Tècnica de Parcs Naturals. Diputació de Barcelona Barcelona Spain
| | - Ricard Casanovas
- Departament de Territori i SostenibilitatGeneralitat de Catalunya Barcelona Spain
| | | | - Frank Pasmans
- Wildlife Health GhentDepartment of PathologyBacteriology and Avian Diseases, Faculty of Veterinary MedicineGhent University Merelbeke Belgium
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45
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Rosa GM, Bosch J, Martel A, Pasmans F, Rebelo R, Griffiths RA, Garner TWJ. Sex‐biased disease dynamics increase extinction risk by impairing population recovery. Anim Conserv 2019. [DOI: 10.1111/acv.12502] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- G. M. Rosa
- Durrell Institute of Conservation and Ecology School of Anthropology and Conservation University of Kent CanterburyKent UK
- Institute of Zoology Zoological Society of London Regent's ParkLondon UK
- Centre for Ecology, Evolution and Environmental Changes (CE3C)Faculdade de Ciências da Universidade de LisboaLisboa Portugal
| | - J. Bosch
- Museo Nacional de Ciencias NaturalesCSIC Madrid Spain
| | - A. Martel
- Department of Pathology, Bacteriology and Avian Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - F. Pasmans
- Department of Pathology, Bacteriology and Avian Diseases Faculty of Veterinary Medicine Ghent University Merelbeke Belgium
| | - R. Rebelo
- Centre for Ecology, Evolution and Environmental Changes (CE3C)Faculdade de Ciências da Universidade de LisboaLisboa Portugal
| | - R. A. Griffiths
- Durrell Institute of Conservation and Ecology School of Anthropology and Conservation University of Kent CanterburyKent UK
| | - T. W. J. Garner
- Institute of Zoology Zoological Society of London Regent's ParkLondon UK
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46
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Verbrugghe E, Van Rooij P, Favoreel H, Martel A, Pasmans F. In vitro modeling of Batrachochytrium dendrobatidis infection of the amphibian skin. PLoS One 2019; 14:e0225224. [PMID: 31725762 PMCID: PMC6855447 DOI: 10.1371/journal.pone.0225224] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/30/2019] [Indexed: 11/19/2022] Open
Abstract
The largest current disease-induced loss of vertebrate biodiversity is due to chytridiomycosis and despite the increasing understanding of the pathogenesis, knowledge unravelling the early host-pathogen interactions remains limited. Batrachochytrium dendrobatidis (Bd) zoospores attach to and invade the amphibian epidermis, with subsequent invasive growth in the host skin. Availability of an in vitro assay would facilitate in depth study of this interaction while reducing the number of experimental animals needed. We describe a fluorescent cell-based in vitro infection model that reproduces host-Bd interactions. Using primary keratinocytes from Litoria caerulea and the epithelial cell line A6 from Xenopus laevis, we reproduced different stages of host cell infection and intracellular growth of Bd, resulting in host cell death, a key event in chytridiomycosis. The presented in vitro models may facilitate future mechanistic studies of host susceptibility and pathogen virulence.
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Affiliation(s)
- Elin Verbrugghe
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
- * E-mail:
| | - Pascale Van Rooij
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Herman Favoreel
- Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
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47
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Peters A, Carver S, Skerratt LF, Meredith A, Woods R. A Solutions-Focused Translational Research Framework for Wildlife Health. Bioscience 2019. [DOI: 10.1093/biosci/biz125] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Abstract
Wildlife health is of emerging relevance for conservation, human health, and domestic animal health. Increased research on wildlife health problems has not been accompanied by a relative increase in effective solutions. Translational research was developed in human health to overcome blocks impeding the development of solutions out of basic research, and a translational research framework is proposed to overcome the same barriers in wildlife health. This framework has four translational phases: problem definition, potential solution development, efficacious solution development, and effective solution development. Implementation of translational research will require a restructuring of the wildlife health research enterprise with a shift, supported by funding sources and journals, to solutions-focused research including later translational phases, the creation of more deeply integrated multidisciplinary and interdisciplinary teams incorporating better representation from human social sciences, and the inclusion of end user and stakeholder participation in all phases of research.
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Affiliation(s)
- Andrew Peters
- Institute of Land, Water and Society and the School of Animal and Veterinary Sciences, Charles Sturt University, Wagga Wagga, Australia
| | - Scott Carver
- Department of Biological Sciences, University of Tasmania, Hobart, Australia
| | - Lee F Skerratt
- Health Research Group, University of Melbourne, Melbourne, Australia
| | - Anna Meredith
- Melbourne Veterinary School, University of Melbourne, Melbourne, Australia
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48
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Canessa S, Bozzuto C, Pasmans F, Martel A. Quantifying the burden of managing wildlife diseases in multiple host species. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2019; 33:1131-1140. [PMID: 30868671 DOI: 10.1111/cobi.13313] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Revised: 12/20/2018] [Accepted: 01/24/2019] [Indexed: 06/09/2023]
Abstract
Mitigation of infectious wildlife diseases is especially challenging where pathogens affect communities of multiple host species. Although most ecological studies recognize the challenge posed by multiple-species pathogens, the implications for management are typically assessed only qualitatively. Translating the intuitive understanding that multiple host species are important into practice requires a quantitative assessment of whether and how secondary host species should also be targeted by management and the effort this will require. Using a multiple-species compartmental model, we determined analytically whether and how intensively secondary host species should be managed to prevent outbreaks in focal hosts based on the reproduction number of individual host species and between-species transmission rates. We applied the model to the invasive pathogenic fungus Batrachochytrium salamandrivorans in a 2-host system in northern Europe. Avoiding a disease outbreak in the focal host (fire salamanders [Salamandra salamandra]) was impossible unless management also heavily targeted the secondary host (alpine newts [Ichthyosaura alpestris]). Preventing an outbreak in the community required targeted removal of at least 80% of each species. This proportion increased to 90% in the presence of an environmental reservoir of B. salamandrivorans and when the proportion of individuals removed could not be adjusted for different host species (e.g., when using traps that are not species specific). We recommend the focus of disease-mitigation plans should shift from focal species to the community level and calculate explicitly the management efforts required on secondary host species to move beyond the simple intuitive understanding that multiple host species may all influence the system. Failure to do so may lead to underestimating the magnitude of the effort required and ultimately to suboptimal or futile management attempts.
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Affiliation(s)
- Stefano Canessa
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - Claudio Bozzuto
- Wildlife Analysis GmbH, Oetlisbergstrasse 38, 8053, Zurich, Switzerland
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820, Merelbeke, Belgium
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49
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The use of geospatial data and Bayesian Networks to assess the risk status of Mexican amphibians. Glob Ecol Conserv 2019. [DOI: 10.1016/j.gecco.2019.e00735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Niederle MV, Bosch J, Ale CE, Nader-Macías ME, Aristimuño Ficoseco C, Toledo LF, Valenzuela-Sánchez A, Soto-Azat C, Pasteris SE. Skin-associated lactic acid bacteria from North American bullfrogs as potential control agents of Batrachochytrium dendrobatidis. PLoS One 2019; 14:e0223020. [PMID: 31560707 PMCID: PMC6764794 DOI: 10.1371/journal.pone.0223020] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 09/11/2019] [Indexed: 11/18/2022] Open
Abstract
The fungal pathogen Batrachochytrium dendrobatidis (Bd) is the causative agent of chytridiomycosis and has been a key driver in the catastrophic decline of amphibians globally. While many strategies have been proposed to mitigate Bd outbreaks, few have been successful. In recent years, the use of probiotic formulations that protect an amphibian host by killing or inhibiting Bd have shown promise as an effective chytridiomycosis control strategy. The North American bullfrog (Lithobates catesbeianus) is a common carrier of Bd and harbours a diverse skin microbiota that includes lactic acid bacteria (LAB), a microbial group containing species classified as safe and conferring host benefits. We investigated beneficial/probiotic properties: anti-Bd activity, and adhesion and colonisation characteristics (hydrophobicity, biofilm formation and exopolysaccharide-EPS production) in two confirmed LAB (cLAB-Enterococcus gallinarum CRL 1826, Lactococcus garvieae CRL 1828) and 60 presumptive LAB (pLAB) [together named as LABs] isolated from bullfrog skin.We challenged LABs against eight genetically diverse Bd isolates and found that 32% of the LABs inhibited at least one Bd isolate with varying rates of inhibition. Thus, we established a score of sensitivity from highest (BdGPL AVS7) to lowest (BdGPL C2A) for the studied Bd isolates. We further reveal key factors underlying host adhesion and colonisation of LABs. Specifically, 90.3% of LABs exhibited hydrophilic properties that may promote adhesion to the cutaneous mucus, with the remaining isolates (9.7%) being hydrophobic in nature with a surface polarity compatible with colonisation of acidic, basic or both substrate types. We also found that 59.7% of LABs showed EPS synthesis and 66.1% produced biofilm at different levels: 21% weak, 29% moderate, and 16.1% strong. Together all these properties enhance colonisation of the host surface (mucus or epithelial cells) and may confer protective benefits against Bd through competitive exclusion. Correspondence analysis indicated that biofilm synthesis was LABs specific with high aggregating bacteria correlating with strong biofilm producers, and EPS producers being correlated to negative biofilm producing LABs. We performed Random Amplified Polymorphic DNA (RAPD)-PCR analysis and demonstrated a higher degree of genetic diversity among rod-shaped pLAB than cocci. Based on the LAB genetic analysis and specific probiotic selection criteria that involve beneficial properties, we sequenced 16 pLAB which were identified as Pediococcus pentosaceus, Enterococcus thailandicus, Lactobacillus pentosus/L. plantarum, L. brevis, and L. curvatus. Compatibility assays performed with cLAB and the 16 species described above indicate that all tested LAB can be included in a mixed probiotic formula. Based on our analyses, we suggest that E. gallinarum CRL 1826, L. garvieae CRL 1828, and P. pentosaceus 15 and 18B represent optimal probiotic candidates for Bd control and mitigation.
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Affiliation(s)
- M. V. Niederle
- Instituto Superior de Investigaciones Biológicas (INSIBIO), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Instituto de Biología “Dr. Francisco D. Barbieri”, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán (UNT), San Miguel de Tucumán, Argentina
| | - J. Bosch
- Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
- Research Unit of Biodiversity (CSIC, UO, PA), Oviedo University—Campus Mieres, Spain
| | - C. E. Ale
- Instituto Superior de Investigaciones Biológicas (INSIBIO), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Instituto de Biología “Dr. Francisco D. Barbieri”, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán (UNT), San Miguel de Tucumán, Argentina
| | - M. E. Nader-Macías
- Centro de Referencia para Lactobacilos (CERELA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Miguel de Tucumán, Argentina
| | - C. Aristimuño Ficoseco
- Centro de Referencia para Lactobacilos (CERELA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Miguel de Tucumán, Argentina
| | - L. F. Toledo
- Laboratório de História Natural de Anfíbios Brasileiros (LaHNAB), Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - A. Valenzuela-Sánchez
- Centro de Investigación para la Sustentabilidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
- Instituto de Ciencias Ambientales y Evolutivas, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
- Organización No Gubernamental (ONG) Ranita de Darwin, Santiago, Chile
- Organización No Gubernamental (ONG) Ranita de Darwin, Valdivia, Chile
| | - C. Soto-Azat
- Centro de Investigación para la Sustentabilidad, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
| | - S. E. Pasteris
- Instituto Superior de Investigaciones Biológicas (INSIBIO), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) and Instituto de Biología “Dr. Francisco D. Barbieri”, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán (UNT), San Miguel de Tucumán, Argentina
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