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Jakóbik J, Drohvalenko M, Fernandez Melendez E, Kępa E, Klynova O, Fedorova A, Korshunov O, Marushchak O, Nekrasova O, Suriadna N, Smirnov N, Tkachenko O, Tupikov A, Dufresnes C, Zinenko O, Pabijan M. Countrywide screening supports model-based predictions of the distribution of Batrachochytrium dendrobatidis in Ukraine. DISEASES OF AQUATIC ORGANISMS 2024; 159:15-27. [PMID: 39087616 DOI: 10.3354/dao03802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Abstract
The chytrid Batrachochytrium dendrobatidis (Bd) is a widespread fungus causing amphibian declines across the globe. Although data on Bd occurrence in Eastern Europe are scarce, a recent species distribution model (SDM) for Bd reported that western and north-western parts of Ukraine are highly suitable to the pathogen. We verified the SDM-predicted range of Bd in Ukraine by sampling amphibians across the country and screening for Bd using qPCR. A total of 446 amphibian samples (tissue and skin swabs) from 11 species were collected from 36 localities. We obtained qPCR-positive results for 33 samples including waterfrogs (Pelophylax esculentus complex) and fire- and yellow-bellied toads (Bombina spp.) from 8 localities. We found that Bd-positive localities had significantly higher predicted Bd habitat suitability than sites that were pathogen-free. Amplification and sequencing of the internal transcribed spacer (ITS) region of samples with the highest Bd load revealed matches with ITS haplotypes of the globally distributed BdGPL strain, and a single case of the BdASIA-2/BdBRAZIL haplotype. We found that Bd was non-randomly distributed across Ukraine, with infections present in the western and north-central forested peripheries of the country with a relatively cool, moist climate. On the other hand, our results suggest that Bd is absent or present in low abundance in the more continental central, southern and eastern regions of Ukraine, corroborating the model-predicted distribution of chytrid fungus. These areas could potentially serve as climatic refugia for Bd-susceptible amphibian hosts.
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Affiliation(s)
- Joanna Jakóbik
- Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, 30-387 Kraków, Poland
| | - Mykola Drohvalenko
- Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, 30-387 Kraków, Poland
- Zoology and Animal Ecology Department, School of Biology, V. N. Karazin Kharkiv National University, 61022 Kharkiv, Ukraine
| | - Eduardo Fernandez Melendez
- Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, 30-387 Kraków, Poland
- Department of Pathobiology, Pharmacology and Zoological Medicine, Faculty of Veterinary Medicine, 9820 Merelbeke, Belgium
| | - Emilia Kępa
- Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, 30-387 Kraków, Poland
| | - Oleksandra Klynova
- Department of Mycology and Plant Resistance, School of Biology, V. N. Karazin Kharkiv National University, 61022 Kharkiv, Ukraine
| | - Anna Fedorova
- Zoology and Animal Ecology Department, School of Biology, V. N. Karazin Kharkiv National University, 61022 Kharkiv, Ukraine
- Laboratory of Fish Genetics, Institute of Animal Physiology and Genetics, Czech Academy of Sciences, 277 21 Liběchov, Czech Republic
| | - Oleksii Korshunov
- Zoology and Animal Ecology Department, School of Biology, V. N. Karazin Kharkiv National University, 61022 Kharkiv, Ukraine
| | - Oleksii Marushchak
- I. I. Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, 01054 Kyiv, Ukraine
- Université de Strasbourg, CNRS, IPHC UMR 7178, 67000 Strasbourg, France
| | - Oksana Nekrasova
- I. I. Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, 01054 Kyiv, Ukraine
- Université de Strasbourg, CNRS, IPHC UMR 7178, 67000 Strasbourg, France
- Department of Ecology, Institute of Life Sciences and Technologies, Daugavpils University, 5401 Daugavpils, Latvia
| | - Natalia Suriadna
- Melitopol Institute of Ecology and Social Technologies of the University Ukraine, 04071 Kyiv, Ukraine
| | - Nazar Smirnov
- Chernivtsi Regional Museum of Local Lore, 58002 Chernivtsi, Ukraine
| | - Oksana Tkachenko
- T.H. Shevchenko National University Chernihiv Colehium, 14013 Chernihiv, Ukraine
| | - Andrii Tupikov
- Society for Conservation GIS Ukraine, Svobody sq. 4, 61022 Kharkiv, Ukraine
| | - Christophe Dufresnes
- Institut de Systématique, Evolution, Biodiversité, Muséum national d'Histoire naturelle, CNRS, Sorbonne Université, EPHE-PSL, Université des Antilles, 75005 Paris, France
| | - Oleksandr Zinenko
- Department of Mycology and Plant Resistance, School of Biology, V. N. Karazin Kharkiv National University, 61022 Kharkiv, Ukraine
| | - Maciej Pabijan
- Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, 30-387 Kraków, Poland
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Borteiro C, Laufer G, Gobel N, Arleo M, Kolenc F, Cortizas S, Barrasso DA, de Sá RO, Soutullo A, Ubilla M, Martínez-Debat C. Widespread occurrence of the amphibian chytrid panzootic lineage in Uruguay is constrained by climate. DISEASES OF AQUATIC ORGANISMS 2024; 158:123-132. [PMID: 38813853 DOI: 10.3354/dao03783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd) causes chytridiomycosis, a disease among the main causes of amphibian declines worldwide. However, Bd studies on Neotropical amphibians from temperate areas are scarce. We present a comprehensive survey of Bd in Uruguay, in temperate central eastern South America, carried out between 2006 and 2014. Skin swabs of 535 specimens of 21 native and exotic frogs were tested by PCR. We used individual-level data to examine the relationship between infection, climatic variables, and their effects on body condition and the number of prey items found in stomach contents. Infection was widespread in free-ranging anurans with an overall prevalence of 41.9%, detected in 15 native species, wild American bullfrogs Aquarana catesbeiana, and captive specimens of Ceratophrys ornata and Xenopus laevis. Three haplotypes of the Bd ITS region were identified in native amphibians, all belonging to the global panzootic lineage (BdGPL), of which only one was present in exotic hosts. Despite high infection frequencies in different anurans, we found no evidence of morbidity or mortality attributable to chytridiomycosis, and we observed no discernible impact on body condition or consumed prey. Climatic conditions at the time of our surveys suggested that the chance of infection is associated with monthly mean temperature, mean humidity, and total precipitation. Temperatures below 21°C combined with moderate humidity and pronounced rainfall may increase the likelihood of infection. Multiple haplotypes of BdGPL combined with high frequencies of infection suggest an enzootic pattern in native species, underscoring the need for continued monitoring.
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Affiliation(s)
- Claudio Borteiro
- Sección Herpetología, Museo Nacional de Historia Natural, Montevideo 11800, Uruguay
| | - Gabriel Laufer
- Área Biodiversidad y Conservación, Museo Nacional de Historia Natural, Montevideo 11800, Uruguay
- Vida Silvestre Uruguay, Montevideo 11100, Uruguay
| | - Noelia Gobel
- Área Biodiversidad y Conservación, Museo Nacional de Historia Natural, Montevideo 11800, Uruguay
- Vida Silvestre Uruguay, Montevideo 11100, Uruguay
| | - Mailén Arleo
- Sección Bioquímica, Departamento de Biología, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Francisco Kolenc
- Sección Herpetología, Museo Nacional de Historia Natural, Montevideo 11800, Uruguay
| | - Sofía Cortizas
- Grupo de Agroecología, Sustentabilidad y Medio Ambiente, Universidad Tecnológica del Uruguay, Durazno 97000, Uruguay
| | - Diego A Barrasso
- Instituto de Diversidad y Evolución Austral (IDEAus-CONICET), and Facultad de Ciencias Naturales y Ciencias de la Salud, Universidad Nacional de la Patagonia 'San Juan Bosco' (UNPSJB), Puerto Madryn 9120, Chubut, Argentina
| | - Rafael O de Sá
- Department of Biology, University of Richmond, Richmond, Virginia 23173, USA
| | - Alvaro Soutullo
- Departamento de Ecología y Gestión Ambiental, Centro Universitario Regional del Este, Punta del Este 20100, Universidad de la República, Uruguay
| | - Martin Ubilla
- Departamento de Paleontología-ICG, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
| | - Claudio Martínez-Debat
- Sección Bioquímica, Departamento de Biología, Facultad de Ciencias, Universidad de la República, Montevideo 11400, Uruguay
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3
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Sauer EL, Venesky MD, McMahon TA, Cohen JM, Bessler S, Brannelly LA, Brem F, Byrne AQ, Halstead N, Hyman O, Johnson PTJ, Richards-Zawacki CL, Rumschlag SL, Sears B, Rohr JR. Are novel or locally adapted pathogens more devastating and why? Resolving opposing hypotheses. Ecol Lett 2024; 27:e14431. [PMID: 38712705 PMCID: PMC11441375 DOI: 10.1111/ele.14431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 05/08/2024]
Abstract
There is a rich literature highlighting that pathogens are generally better adapted to infect local than novel hosts, and a separate seemingly contradictory literature indicating that novel pathogens pose the greatest threat to biodiversity and public health. Here, using Batrachochytrium dendrobatidis, the fungus associated with worldwide amphibian declines, we test the hypothesis that there is enough variance in "novel" (quantified by geographic and phylogenetic distance) host-pathogen outcomes to pose substantial risk of pathogen introductions despite local adaptation being common. Our continental-scale common garden experiment and global-scale meta-analysis demonstrate that local amphibian-fungal interactions result in higher pathogen prevalence, pathogen growth, and host mortality, but novel interactions led to variable consequences with especially virulent host-pathogen combinations still occurring. Thus, while most pathogen introductions are benign, enough variance exists in novel host-pathogen outcomes that moving organisms around the planet greatly increases the chance of pathogen introductions causing profound harm.
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Affiliation(s)
- Erin L Sauer
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA
- Department of Integrative Biology, University of South Florida, Tampa, Florida, USA
| | - Matthew D Venesky
- Department of Integrative Biology, University of South Florida, Tampa, Florida, USA
- Department of Biology, Allegheny College, Meadville, Pennsylvania, USA
| | - Taegan A McMahon
- Department of Integrative Biology, University of South Florida, Tampa, Florida, USA
- Biology Department, Connecticut College, New London, Connecticut, USA
| | - Jeremy M Cohen
- Department of Integrative Biology, University of South Florida, Tampa, Florida, USA
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, Connecticut, USA
| | - Scott Bessler
- Department of Integrative Biology, University of South Florida, Tampa, Florida, USA
| | - Laura A Brannelly
- Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana, USA
- Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Melbourne, Victoria, Australia
| | - Forrest Brem
- Biology Department, University of Memphis, Memphis, Tennessee, USA
| | - Allison Q Byrne
- Department of Environmental Science, Policy, and Management, University of California, Berkeley, California, USA
| | - Neal Halstead
- Department of Integrative Biology, University of South Florida, Tampa, Florida, USA
- Wildlands Conservation, Tampa, Florida, USA
| | - Oliver Hyman
- Biology Department, James Madison University, Harrisonburg, Virginia, USA
| | - Pieter T J Johnson
- Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, USA
| | - Corinne L Richards-Zawacki
- Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana, USA
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Samantha L Rumschlag
- Department of Biology, Miami University, Oxford, Ohio, USA
- U.S. Environmental Protection Agency, Office of Research and Development, Center for Computational Toxicology and Exposure, Great Lakes Toxicology and Ecology Division, Duluth, Minnesota, USA
| | - Brittany Sears
- Department of Integrative Biology, University of South Florida, Tampa, Florida, USA
| | - Jason R Rohr
- Department of Integrative Biology, University of South Florida, Tampa, Florida, USA
- Department of Biological Sciences, University of Notre Dame, South Bend, Indiana, USA
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Mulder KP, Savage AE, Gratwicke B, Longcore JE, Bronikowski E, Evans M, Longo AV, Kurata NP, Walsh T, Pasmans F, McInerney N, Murray S, Martel A, Fleischer RC. Sequence capture identifies fastidious chytrid fungi directly from host tissue. Fungal Genet Biol 2024; 170:103858. [PMID: 38101696 DOI: 10.1016/j.fgb.2023.103858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 12/04/2023] [Accepted: 12/12/2023] [Indexed: 12/17/2023]
Abstract
The chytrid fungus Batrachochytrium dendrobatidis (Bd) was discovered in 1998 as the cause of chytridiomycosis, an emerging infectious disease causing mass declines in amphibian populations worldwide. The rapid population declines of the 1970s-1990s were likely caused by the spread of a highly virulent lineage belonging to the Bd-GPL clade that was introduced to naïve susceptible populations. Multiple genetically distinct and regional lineages of Bd have since been isolated and sequenced, greatly expanding the known biological diversity within this fungal pathogen. To date, most Bd research has been restricted to the limited number of samples that could be isolated using culturing techniques, potentially causing a selection bias for strains that can grow on media and missing other unculturable or fastidious strains that are also present on amphibians. We thus attempted to characterize potentially non-culturable genetic lineages of Bd from distinct amphibian taxa using sequence capture technology on DNA extracted from host tissue and swabs. We focused our efforts on host taxa from two different regions that likely harbored distinct Bd clades: (1) wild-caught leopard frogs (Rana) from North America, and (2) a Japanese Giant Salamander (Andrias japonicus) at the Smithsonian Institution's National Zoological Park that exhibited signs of disease and tested positive for Bd using qPCR, but multiple attempts failed to isolate and culture the strain for physiological and genetic characterization. We successfully enriched for and sequenced thousands of fungal genes from both host clades, and Bd load was positively associated with number of recovered Bd sequences. Phylogenetic reconstruction placed all the Rana-derived strains in the Bd-GPL clade. In contrast, the A. japonicus strain fell within the Bd-Asia3 clade, expanding the range of this clade and generating additional genomic data to confirm its placement. The retrieved ITS locus matched public barcoding data from wild A. japonicus and Bd infections found on other amphibians in India and China, suggesting that this uncultured clade is widespread across Asia. Our study underscores the importance of recognizing and characterizing the hidden diversity of fastidious strains in order to reconstruct the spatiotemporal and evolutionary history of Bd. The success of the sequence capture approach highlights the utility of directly sequencing pathogen DNA from host tissue to characterize cryptic diversity that is missed by culture-reliant approaches.
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Affiliation(s)
- Kevin P Mulder
- Wildlife Health Ghent, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium; Center for Conservation Genomics, Smithsonian National Zoo and Conservation Biology Institute, Washington, DC, USA.
| | - Anna E Savage
- Department of Biology, University of Central Florida, Orlando, FL, USA
| | - Brian Gratwicke
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, USA
| | - Joyce E Longcore
- School of Biology and Ecology, University of Maine, Orono, ME, USA
| | - Ed Bronikowski
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, USA
| | - Matthew Evans
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, USA
| | - Ana V Longo
- Department of Biology, University of Florida, Gainesville, FL, USA
| | - Naoko P Kurata
- Center for Conservation Genomics, Smithsonian National Zoo and Conservation Biology Institute, Washington, DC, USA; Department of Natural Resources and the Environment, Cornell University, Ithaca, NY, USA; Department of Ichthyology, American Museum of Natural History, New York, NY, USA
| | - Tim Walsh
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, USA
| | - Frank Pasmans
- Wildlife Health Ghent, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Nancy McInerney
- Center for Conservation Genomics, Smithsonian National Zoo and Conservation Biology Institute, Washington, DC, USA
| | - Suzan Murray
- Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC, USA
| | - An Martel
- Wildlife Health Ghent, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Robert C Fleischer
- Center for Conservation Genomics, Smithsonian National Zoo and Conservation Biology Institute, Washington, DC, USA
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Sun D, Herath J, Zhou S, Ellepola G, Meegaskumbura M. Associations of Batrachochytrium dendrobatidis with skin bacteria and fungi on Asian amphibian hosts. ISME COMMUNICATIONS 2023; 3:123. [PMID: 37993728 PMCID: PMC10665332 DOI: 10.1038/s43705-023-00332-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Revised: 11/07/2023] [Accepted: 11/09/2023] [Indexed: 11/24/2023]
Abstract
Amphibian skin harbors microorganisms that are associated with the fungal pathogen Batrachochytrium dendrobatidis (Bd), which causes chytridiomycosis, one of the most significant wildlife diseases known. This pathogen originated in Asia, where diverse Bd lineages exist; hence, native amphibian hosts have co-existed with Bd over long time periods. Determining the nuances of this co-existence is crucial for understanding the prevalence and spread of Bd from a microbial context. However, associations of Bd with the natural skin microbiome remain poorly understood for Asian hosts, especially in relation to skin-associated fungi. We used 16 S rRNA and fungal internal transcribed spacer (ITS) gene sequencing to characterize the skin microbiome of four native Asian amphibian species and examined the relationships between Bd infection and their skin bacterial and fungal communities; we also analyzed the correlates of the putative anti-Bd bacteria. We show that both skin bacterial and fungal community structure and composition had significant associations with infection status (Bd presence/absence) and infection intensity (frequency of Bd sequence reads). We also found that the putative anti-Bd bacterial richness was correlated with Bd infection status and infection intensity, and observed that the relative abundance of anti-Bd bacteria roughly correspond with changes in both Bd prevalence and mean infection intensity in populations. Additionally, the microbial co-occurrence network of infected frogs was significantly different from that of uninfected frogs that were characterized by more keystone nodes (connectors) and larger proportions in correlations between bacteria, suggesting stronger inter-module bacterial interactions. These results indicate that the mutual effects between Bd and skin-associated microbiome, including the interplay between bacteria and fungi, might vary with Bd infection in susceptible amphibian species. This knowledge will help in understanding the dynamics of Bd from a microbial perspective, potentially contributing to mitigate chytridiomycosis in other regions of the world.
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Affiliation(s)
- Dan Sun
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, 530000, People's Republic of China
| | - Jayampathi Herath
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, 530000, People's Republic of China
- School of Biomedical Sciences, International Institute of Health Sciences (IIHS), No 704 Negombo Rd, Welisara, 71722, Sri Lanka
| | - Shipeng Zhou
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, 530000, People's Republic of China
| | - Gajaba Ellepola
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, 530000, People's Republic of China
- Department of Zoology, Faculty of Science, University of Peradeniya, Peradeniya, KY20400, Sri Lanka
| | - Madhava Meegaskumbura
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning, Guangxi, 530000, People's Republic of China.
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Sun D, Ellepola G, Herath J, Meegaskumbura M. Ecological Barriers for an Amphibian Pathogen: A Narrow Ecological Niche for Batrachochytrium salamandrivorans in an Asian Chytrid Hotspot. J Fungi (Basel) 2023; 9:911. [PMID: 37755019 PMCID: PMC10532633 DOI: 10.3390/jof9090911] [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: 08/08/2023] [Revised: 09/02/2023] [Accepted: 09/05/2023] [Indexed: 09/28/2023] Open
Abstract
The chytrid fungal pathogens Batrachochytrium salamandrivorans (Bsal) and B. dendrobatidis (Bd) are driving amphibian extinctions and population declines worldwide. As their origins are believed to be in East/Southeast Asia, this region is crucial for understanding their ecology. However, Bsal screening is relatively limited in this region, particularly in hotspots where Bd lineage diversity is high. To address this gap, we conducted an extensive Bsal screening involving 1101 individuals from 36 amphibian species, spanning 17 natural locations and four captive facilities in the biodiversity-rich Guangxi Zhuang Autonomous Region (GAR). Our PCR assays yielded unexpected results, revealing the complete absence of Bsal in all tested samples including 51 individuals with Bd presence. To understand the potential distribution of Bsal, we created niche models, utilizing existing occurrence records from both Asia and Europe. These models estimated potential suitable habitats for Bsal largely in the northern and southwestern parts of the GAR. Although Bsal was absent in our samples, the niche models identified 10 study sites as being potentially suitable for this pathogen. Interestingly, out of these 10 sites, Bd was detected at 8. This suggests that Bsal and Bd could possibly co-exist in these habitats, if Bsal were present. Several factors seem to influence the distribution of Bsal in Asia, including variations in temperature, local caudate species diversity, elevation, and human population density. However, it is climate-related factors that hold the greatest significance, accounting for a notable 60% contribution. The models propose that the specific climatic conditions of arid regions, primarily seen in the GAR, play a major role in the distribution of Bsal. Considering the increased pathogenicity of Bsal at stable and cooler temperatures (10-15 °C), species-dependent variations, and the potential for seasonal Bd-Bsal interactions, we emphasize the importance of periodic monitoring for Bsal within its projected range in the GAR. Our study provides deeper insights into Bsal's ecological niche and the knowledge generated will facilitate conservation efforts in amphibian populations devastated by chytrid pathogens across other regions of the world.
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Affiliation(s)
- Dan Sun
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China; (D.S.)
| | - Gajaba Ellepola
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China; (D.S.)
- Department of Zoology, Faculty of Science, University of Peradeniya, Peradeniya, Kandy 20400, Sri Lanka
| | - Jayampathi Herath
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China; (D.S.)
- School of Biomedical Sciences, International Institute of Health Sciences (IIHS), No. 704 Negombo Road, Welisara 71722, Sri Lanka
| | - Madhava Meegaskumbura
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530000, China; (D.S.)
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7
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Zhang J, Wang S, Xu C, Wang S, Du J, Niu M, Yang J, Li Y. Pathogenic selection promotes adaptive immune variations against serious bottlenecks in early invasions of bullfrogs. iScience 2023; 26:107316. [PMID: 37539025 PMCID: PMC10393753 DOI: 10.1016/j.isci.2023.107316] [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: 04/08/2023] [Revised: 05/22/2023] [Accepted: 07/04/2023] [Indexed: 08/05/2023] Open
Abstract
Adaptive genetic variations are key for understanding evolutionary processes influencing invasions. However, we have limited knowledge on how adaptive genetic diversity in invasive species responds to new pathogenic environments. Here, we compared variations in immune major histocompatibility complex (MHC) class-II β gene and neutral loci in relation to pathogenic chytrid fungus (Batrachochytrium dendrobatidis, Bd) infection across invasive and native populations of American bullfrog between China and United States (US). Chinese invasive populations show a 60% reduction in neutral cytb variations relative to US native populations, and there were similar MHC variation and functional diversity between them. One MHC allele private to China was under recent positive selection and associated with decreased Bd infection, partly explaining the lower Bd prevalence for Chinese populations than for native US populations. These results suggest that pathogen-mediated selection favors adaptive MHC variations and functional diversity maintenance against serious bottlenecks during the early invasions (within 15 generations) of bullfrogs.
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Affiliation(s)
- Jiaqi Zhang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang, Beijing 100101, China
- University of Chinese Academy of Sciences Beijing 100049, China
| | - Supen Wang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang, Beijing 100101, China
| | - Chunxia Xu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang, Beijing 100101, China
- University of Chinese Academy of Sciences Beijing 100049, China
| | - Siqi Wang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang, Beijing 100101, China
- University of Chinese Academy of Sciences Beijing 100049, China
| | - Jiacong Du
- School of Life Sciences, Institute of Life Sciences and Green Development, Hebei University, Baoding 071002, China
| | - Meiling Niu
- School of Life Sciences, Institute of Life Sciences and Green Development, Hebei University, Baoding 071002, China
| | - Jiaxue Yang
- School of Life Sciences, Institute of Life Sciences and Green Development, Hebei University, Baoding 071002, China
| | - Yiming Li
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang, Beijing 100101, China
- University of Chinese Academy of Sciences Beijing 100049, China
- School of Life Sciences, Institute of Life Sciences and Green Development, Hebei University, Baoding 071002, China
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Gentry S, Lorch JM, Lankton JS, Pringle A. A Cross-Inoculation Experiment Reveals that Ophidiomyces ophiodiicola and Nannizziopsis guarroi Can Each Infect Both Snakes and Lizards. Appl Environ Microbiol 2023; 89:e0216822. [PMID: 37098892 PMCID: PMC10231240 DOI: 10.1128/aem.02168-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/03/2023] [Indexed: 04/27/2023] Open
Abstract
Host range and specificity are key concepts in the study of infectious diseases. However, both concepts remain largely undefined for many influential pathogens, including many fungi within the Onygenales order. This order encompasses reptile-infecting genera (Nannizziopsis, Ophidiomyces, and Paranannizziopsis) formerly classified as the Chrysosporium anamorph of Nannizziopsis vriesii (CANV). The reported hosts of many of these fungi represent a narrow range of phylogenetically related animals, suggesting that many of these disease-causing fungi are host specific, but the true number of species affected by these pathogens is unknown. For example, to date, Nannizziopsis guarroi (the causative agent of yellow fungus disease) and Ophidiomyces ophiodiicola (the causative agent of snake fungal disease) have been documented only in lizards and snakes, respectively. In a 52-day reciprocal-infection experiment, we tested the ability of these two pathogens to infect currently unreported hosts, inoculating central bearded dragons (Pogona vitticeps) with O. ophiodiicola and corn snakes (Pantherophis guttatus) with N. guarroi. We confirmed infection by documenting both clinical signs and histopathological evidence of fungal infection. Our reciprocity experiment resulted in 100% of corn snakes and 60% of bearded dragons developing infections with N. guarroi and O. ophiodiicola, respectively, demonstrating that these fungal pathogens have a broader host range than previously thought and that hosts with cryptic infections may play a role in pathogen translocation and transmission. IMPORTANCE Our experiment using Ophidiomyces ophiodiicola and Nannizziopsis guarroi is the first to look more critically at these pathogens' host range. We are the first to identify that both fungal pathogens can infect both corn snakes and bearded dragons. Our findings illustrate that both fungal pathogens have a more general host range than previously known. Additionally, there are significant implications concerning the spread of snake fungal disease and yellow fungus disease in popular companion animals and the increased chance of disease spillover into other wild and naive populations.
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Affiliation(s)
- Savannah Gentry
- University of Wisconsin—Madison, Department of Botany, Madison, Wisconsin, USA
| | - Jeffrey M. Lorch
- U.S. Geological Survey, National Wildlife Health Center, Madison, Wisconsin, USA
| | - Julia S. Lankton
- U.S. Geological Survey, National Wildlife Health Center, Madison, Wisconsin, USA
| | - Anne Pringle
- University of Wisconsin—Madison, Department of Botany, Madison, Wisconsin, USA
- University of Wisconsin—Madison, Department of Bacteriology, Madison, Wisconsin, USA
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9
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First Survey of the Pathogenic Fungus Batrachochytrium dendrobatidis in Wild Populations of the Yunnan Caecilian (Ichthyophis bannanicus) in Guangxi, China. J Wildl Dis 2022; 58:450-453. [PMID: 35113986 DOI: 10.7589/jwd-d-21-00133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 11/04/2021] [Indexed: 11/20/2022]
Abstract
Batrachochytrium dendrobatidis (Bd), which causes chytridiomycosis, mainly infects Anura and Caudata but is poorly known in Gymnophiona. We conducted a survey of Bd in the Yunnan caecilian (Ichthyophis bannanicus) and found that 6 of 71 samples (8.4%) tested positive for Bd. To our knowledge, this is the first detection of Bd in wild I. bannanicus.
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10
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Distribution and Genetic Diversity of the Amphibian Chytrid in Japan. J Fungi (Basel) 2021; 7:jof7070522. [PMID: 34210103 PMCID: PMC8307550 DOI: 10.3390/jof7070522] [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: 05/19/2021] [Revised: 06/25/2021] [Accepted: 06/27/2021] [Indexed: 11/28/2022] Open
Abstract
While research on frog chytrid fungus Batrachochytrium dendrobatidis (Bd), an infectious disease that threatens amphibian diversity, continues to advance worldwide, little progress has been made in Japan since around 2010. The reason for this is, which we pointed out in 2009, that the origin of frog chytrid fungus may be in the East Asian region, including Japan based on the Bd ITS-DNA variation, and as few cases of mass mortality caused by this fungus have been observed in wild amphibian populations in Japan, the interest of the Japanese government and the general public in Bd has waned. However, we believe that organizing the data obtained so far in Japan and distributing the status of frog chytrid fungus in Japan to the world will provide useful insight for future risk management of this pathogen. We collected more than 5500 swab samples from wild amphibians throughout Japan from 2009 to 2010. Then, we investigated the infection status using the Nested-PCR method. We sequenced the obtained DNA samples and constructed a maximum-parsimony (MP) tree to clarify the phylogenetic diversity of Bd. We detected Bd infection in 11 (nine native and two alien) amphibian species in Japan and obtained 44 haplotypes of Bd ITS-DNA. The MP tree showed a high diversity of Bd strains in Japan, suggesting that some strains belong to Bd-GPL and Bd-Brazil. Except for local populations of the Japanese giant salamanders Andrias japonicus in Honshu Island and the sword tail newts Cynops ensicauda in Okinawa Island, the Bd infection prevalence in native amphibian species was very low. The alien bullfrog Aquarana catesbeiana had high Bd infection rates in all areas where they were sampled. No Bd infection was detected in other native amphibians in the areas where giant salamanders, sword tail newts, and bullfrogs were collected, suggesting that many native amphibians are resistant to Bd infection. The sword tail newt of Okinawa Island had both the highest infectious incidence and greatest number of haplotypes. The giant salamanders also showed relatively high infection prevalence, but the infected strains were limited to those specific to this species. These two Caudata species are endemic to a limited area of Japan, and it was thought that they may have been refugia for Bd, which had been distributed in Japan Islands for a long time.
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11
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Chytridiomycosis in Asian Amphibians, a Global Resource for Batrachochytrium dendrobatidis (Bd) Research. J Indian Inst Sci 2021; 101:227-241. [PMID: 34092943 PMCID: PMC8171229 DOI: 10.1007/s41745-021-00227-3] [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: 01/14/2021] [Accepted: 03/25/2021] [Indexed: 12/01/2022]
Abstract
Chytridiomycosis is an emerging infectious disease affecting amphibians globally and it is caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd). Chytridiomycosis has caused dramatic declines and even extinctions in wild amphibian populations in Europe, Australia, Central and North America. Spanning over two and a half decades, extensive research has led to discovery of epizootic and enzootic lineages of this pathogen. However, the Bd–amphibian system had garnered less attention in Asia until recently when an ancestral Bd lineage was identified in the Korean peninsula. Amphibians co-exist with the pathogen in Asia, only sub-lethal effects have been documented on hosts. Such regions are ‘coldspots’ of infection and are an important resource to understand the dynamics between the enzootic pathogen—Bd and its obligate host—amphibians. Insights into the biology of infection have provided new knowledge on the multi-faceted interaction of Bd in a hyperdiverse Asian amphibian community. We present the findings and highlight the knowledge gap that exists, and propose the ways to bridge them. We emphasize that chytridiomycosis in Asia is an important wildlife disease and it needs focussed research, as it is a dynamic front of pathogen diversity and virulence.
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12
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Li W, Hou X, Xu C, Qin M, Wang S, Wei L, Wang Y, Liu X, Li Y. Validating eDNA measurements of the richness and abundance of anurans at a large scale. J Anim Ecol 2021; 90:1466-1479. [PMID: 33694188 DOI: 10.1111/1365-2656.13468] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 02/17/2021] [Indexed: 02/06/2023]
Abstract
In some situations, environmental DNA (eDNA) metabarcoding is a more accurate tool for measuring species richness of a taxon than conventional methods. Whether this tool can reliably estimate the abundance of a taxon remains unresolved. We examined the reliability of metabarcoding for measuring anuran diversity compared to a commonly used traditional line transect method (TLTM) through the replicate sampling of three visits across 71 waterbodies (ponds or reservoirs) in Liuheng, China. We also investigated the relative contributions of species-specific characteristics and the physiochemical properties of a waterbody on the relative read count across species and waterbodies. We found that eDNA metabarcoding had a higher detection probability for each of seven anuran species found in the sampling region than TLTM. Furthermore, the relative read count estimated by metabarcoding was positively correlated with the density or relative density of individuals identified with the TLTM across waterbodies for every species. Species-specific characteristics of anurans, such as density, relative density, body mass, biomass and relative biomass, accounted for substantial variations in the read count across species and waterbodies, while physiochemical factors, including pH, temperature, water volume, vegetation and elevation, had little effect on the read count. Our results based on robust sampling suggest that metabarcoding enables more reliable and efficient measurements of anuran occurrence at a large scale during a short-term survey (within 15 days) than that obtained by the TLTM, and offers an alternative tool for quantifications of anuran abundance. Density or biomass is better and more reliable indicator of anuran abundance associated with read count than relative density or relative biomass.
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Affiliation(s)
- Wenhao Li
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Xianglei Hou
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Chunxia Xu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Mingshuo Qin
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Supen Wang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, The Chinese Academy of Sciences, Beijing, China
| | - Li Wei
- College of Ecology, Lishui University, Lishui, China
| | - Yanping Wang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Science, Nanjing Normal University, Nanjing, China
| | - Xuan Liu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, The Chinese Academy of Sciences, Beijing, China
| | - Yiming Li
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, The Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
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13
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Rahman MM, Jahan H, Rabbe MF, Chakraborty M, Salauddin M. First Detection of Batrachochytrium dendrobatidis in Wild Frogs from Bangladesh. ECOHEALTH 2021; 18:31-43. [PMID: 34028636 DOI: 10.1007/s10393-021-01522-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 02/25/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
Global amphibian populations are facing a novel threat, chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), which is responsible for the severe decline of a number of species across several continents. Chytridiomycosis in Asia is a relatively recent discovery yet there have been no reports on Bd-presence in Bangladeshi amphibians. We conducted a preliminary study on 133 wild frogs from seven sites in Bangladesh between April and July 2018. Nested PCR analysis showed 20 samples (15.04%) and 50% of the tested taxa (9 species from 6 genera and 4 families) as Bd-positive. Eight of the nine species are discovered as newly infected hosts. Analysis of Bd-positive samples shows prevalence does not significantly vary among different land cover categories, although the occurrence is higher in forested areas. The prevalence rate is similar in high and low disturbed areas, but the range of occurrence is statistically higher in low disturbance areas. Maximum entropy distribution modeling indicates high probabilities of Bd occurrence in hilly and forested areas in southeast and central-north Bangladesh. The Bd-specific ITS1-5.8S-ITS2 ribosomal gene sequence from the Bd-positive samples tested is completely identical. A neighbor-joining phylogenetic tree reveals that the identified strain shares a common ancestry with strains previously discovered in different Asian regions. Our results provide the first evidence of Bd-presence in Bangladeshi amphibians, inferring that diversity is at risk. The effects of environmental and climatic factors along with quantitative PCR analysis are required to determine the infection intensity and susceptibility of amphibians in the country.
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Affiliation(s)
- Md Mokhlesur Rahman
- Department of Zoology, University of Dhaka, Dhaka, 1000, Bangladesh.
- Department of Anthropology, Durham University, South Road, Durham, DH1 3LE, UK.
| | - Hawa Jahan
- Department of Zoology, University of Dhaka, Dhaka, 1000, Bangladesh
- Division of Evolution and Genomic Sciences, FBMH, School of Biological Sciences, University of Manchester, Oxford Rd, Manchester, M13 9PT, UK
| | - Md Fazle Rabbe
- Department of Zoology, University of Dhaka, Dhaka, 1000, Bangladesh
| | | | - Md Salauddin
- Department of Geography and Environment, Jagannath University, Dhaka, 1100, Bangladesh
- Disaster Risk Management Department, Bangladesh Red Crescent Society, Red Crescent Sarak, Bara Moghbazar, Dhaka, 1217, Bangladesh
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14
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Grogan LF, Humphries JE, Robert J, Lanctôt CM, Nock CJ, Newell DA, McCallum HI. Immunological Aspects of Chytridiomycosis. J Fungi (Basel) 2020; 6:jof6040234. [PMID: 33086692 PMCID: PMC7712659 DOI: 10.3390/jof6040234] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/14/2020] [Accepted: 10/15/2020] [Indexed: 12/27/2022] Open
Abstract
Amphibians are currently the most threatened vertebrate class, with the disease chytridiomycosis being a major contributor to their global declines. Chytridiomycosis is a frequently fatal skin disease caused by the fungal pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal). The severity and extent of the impact of the infection caused by these pathogens across modern Amphibia are unprecedented in the history of vertebrate infectious diseases. The immune system of amphibians is thought to be largely similar to that of other jawed vertebrates, such as mammals. However, amphibian hosts are both ectothermic and water-dependent, which are characteristics favouring fungal proliferation. Although amphibians possess robust constitutive host defences, Bd/Bsal replicate within host cells once these defences have been breached. Intracellular fungal localisation may contribute to evasion of the induced innate immune response. Increasing evidence suggests that once the innate defences are surpassed, fungal virulence factors suppress the targeted adaptive immune responses whilst promoting an ineffectual inflammatory cascade, resulting in immunopathology and systemic metabolic disruption. Thus, although infections are contained within the integument, crucial homeostatic processes become compromised, leading to mortality. In this paper, we present an integrated synthesis of amphibian post-metamorphic immunological responses and the corresponding outcomes of infection with Bd, focusing on recent developments within the field and highlighting future directions.
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Affiliation(s)
- Laura F. Grogan
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Southport, QLD 4222, Australia;
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia; (J.E.H.); (D.A.N.)
- Correspondence:
| | - Josephine E. Humphries
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia; (J.E.H.); (D.A.N.)
| | - Jacques Robert
- University of Rochester Medical Center, Rochester, NY 14642, USA;
| | - Chantal M. Lanctôt
- Australian Rivers Institute, Griffith University, Southport, QLD 4222, Australia;
| | - Catherine J. Nock
- Southern Cross Plant Science, Southern Cross University, Lismore, NSW 2480, Australia;
| | - David A. Newell
- Forest Research Centre, School of Environment, Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia; (J.E.H.); (D.A.N.)
| | - Hamish I. McCallum
- Environmental Futures Research Institute and School of Environment and Science, Griffith University, Southport, QLD 4222, Australia;
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15
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Gong M, Shafer ABA, Hu X, Huang Y, Zhang L, Li H, Wu Y, Wen W, Liu G. Population demographic history and adaptability of the vulnerable Lolokou Sucker Frog. Genetica 2020; 148:207-213. [PMID: 33052504 DOI: 10.1007/s10709-020-00105-3] [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: 01/13/2020] [Accepted: 09/26/2020] [Indexed: 11/30/2022]
Abstract
Amphibians are experiencing worldwide declines due to increasing anthropogenetic disturbances. However, the genetic variability and hence adaptability are still unknown for most frogs. We integrated the mitochondrial (ND2 gene), nuclear (TYR gene) and major histocompatibility complex (MHC) loci, to clarify the demographic patterns and immune-gene diversity of the Lolokou Sucker Frog (Amolops loloensis). Demographic analysis of the ND2 and TYR genes suggested that the Lolokou Sucker Frog experienced a population expansion within the last 10,000 years. High MHC diversity was detected, which has likely resulted from positive selection, indicating the current diversity bodes well for the species' adaptive potential to pathogenic challenges. These findings broaden our knowledge on the population history and evolution adaptation of the reclusive torrent frog, and conservation implications are provided.
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Affiliation(s)
- Minghao Gong
- Institute of Wetland Research, Beijing Key Laboratory of Wetland Services and Restoration, Chinese Academy of Forestry, Beijing, 100091, China
| | - Aaron B A Shafer
- Forensics & Environmental and Life Sciences, Trent University, Peterborough, 7K9J 7B8, Canada
| | - Xiaolong Hu
- College of Nature Conservation, Beijing Forestry University, Beijing, 100083, China
| | - Yaohua Huang
- Mabian Dafengding National Nature Reserve, Sichuan, 614600, China
| | - Ling Zhang
- China Wildlife Conservation Association, Beijing, 100714, China
| | - Huixin Li
- Institute of Wetland Research, Beijing Key Laboratory of Wetland Services and Restoration, Chinese Academy of Forestry, Beijing, 100091, China
| | - Ye Wu
- Mabian Dafengding National Nature Reserve, Sichuan, 614600, China
| | - Wanyu Wen
- Institute of Wetland Research, Beijing Key Laboratory of Wetland Services and Restoration, Chinese Academy of Forestry, Beijing, 100091, China
| | - Gang Liu
- Institute of Wetland Research, Beijing Key Laboratory of Wetland Services and Restoration, Chinese Academy of Forestry, Beijing, 100091, China.
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16
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Reproductive characteristics of American bullfrogs (Lithobates catesbeianus) in their invasive range of the Pacific Northwest, USA. Sci Rep 2020; 10:16271. [PMID: 33004879 PMCID: PMC7529884 DOI: 10.1038/s41598-020-73206-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 06/26/2020] [Indexed: 02/06/2023] Open
Abstract
Invasive species pose a major threat to global biodiversity. The effects of invasive species can be strongly influenced and potentially mediated by their reproductive characteristics, such as fecundity, egg production, and duration and number of reproductive events. Selection for smaller body size at first reproduction can also play a role in their establishment, facilitating colonization and spread. The American bullfrog, native to the eastern U.S. (Lithobates catesbeianus), is a species that has invaded more than 40 countries across 4 continents. This species has become especially prevalent in the western United States since its introduction in the early 1900s. This study characterized reproductive characteristics of bullfrogs with emphasis on the minimum size at which males and females reach sexual maturity in the Willamette Valley, Oregon, USA invasion range. We collected and dissected 121 individuals in 2013 and 2017, quantifying characteristics of sexual maturity including snout-vent length, total length, sex, tympanum diameter, presence of distended oviducts or eggs for females, and testes length and sperm activity in males. Our results showed that the minimum reproductive size of both males and females was smaller relative to bullfrogs in their native range as well as in populations across their invasive range. Reduction in size at reproductive maturity is likely impacting the invasive success of American bullfrogs and this study gives us insight on management actions to control the invasion. Applying this insight, managers can adjust their definition of reproductively active adults, increasing the target population of culling and other control methods.
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17
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Recommendations for IUCN Red List Conservation Status of the “Dryophytes immaculatus Group” in North East Asia. DIVERSITY 2020. [DOI: 10.3390/d12090336] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Threat assessment is important to prioritize species conservation projects and planning. The taxonomic resolution regarding the status of the “Dryophytes immaculatus group” and the description of a new species in the Republic of Korea resulted in a shift in ranges and population sizes. Thus, reviewing the IUCN Red List status of the three species from the group: D. immaculatus, D. suweonensis and D. flaviventris and recommending an update is needed. While the three species have similar ecological requirements and are distributed around the Yellow Sea, they are under contrasting anthropological pressure and threats. Here, based on the literature available, I have applied all IUCN Red List criterion and tested the fit of each species in each criteria to recommend listing under the appropriate threat level. This resulted in the recommendation of the following categories: Near Threatened for D. immaculatus, Endangered following the criteria C2a(i)b for D. suweonensis and Critically Endangered following the criteria E for D. flaviventris. All three species are declining, mostly because of landscape changes as a result of human activities, but the differences in range, population dynamics and already extirpated subpopulations result in different threat levels for each species. Dryophytes flaviventris is under the highest threat category mostly because of its limited range segregated into two subpopulations; and several known extirpated subpopulations. Immediate actions for the conservation of this species are required. Dryophytes suweonensis is present in both the Republic of Korea and the Democratic Republic of Korea (DPR Korea) and is under lower ecological pressure in DPR Korea. Dryophytes immaculatus is present in the People’s Republic of China, over a very large range despite a marked decline. I recommend joint efforts for the conservation of these species.
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18
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Chen C, Chen C, Wang Y. Ecological correlates of extinction risk in Chinese amphibians. DIVERS DISTRIB 2019. [DOI: 10.1111/ddi.12961] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Affiliation(s)
- Chuanwu Chen
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences Nanjing Normal University Nanjing China
| | | | - Yanping Wang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences Nanjing Normal University Nanjing China
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19
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Zhang M, Gaughan S, Chang Q, Chen H, Lu G, Wang X, Xu L, Zhu L, Jiang J. Age-related changes in the gut microbiota of the Chinese giant salamander (Andrias davidianus). Microbiologyopen 2018; 8:e00778. [PMID: 30585426 PMCID: PMC6612560 DOI: 10.1002/mbo3.778] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 11/13/2018] [Accepted: 11/13/2018] [Indexed: 01/24/2023] Open
Abstract
The composition of the intestinal microbial community may vary across developmental stages. In this study, we explored how this microbial community shifted along the intestinal tract of the Chinese giant salamander (Andrias davidianus) at various ages. Next-generation sequencing was used to sequence the bacterial 16S rRNA gene from different kind of samples, including the stomach, duodenum, ileum, and rectum. The highest mean relative abundance of the bacterial community in the gastrointestinal tract shifted in relation to age: within the first year, Bacteroidetes (47.76%) dominated the gut microbiome, whereas Proteobacteria was the most dominant at age 2 (32.88%) and age 3 (30.78%), and finally, Firmicutes was the most dominant at age 4 (34.70%). The overall richness of the gut bacterial community also generally increased from age 2 to 4. Hierarchical cluster analysis revealed that the gut microbiome at age 2 had greater variability than that at either age 3 or 4, likely representing a shift in diet from yolk or redworms as a juvenile to shrimp or crab as an adult. As these salamanders develop, their gastrointestinal tracts increase in complexity, and this compartmentalization may also facilitate an increase in microbial gut diversity.
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Affiliation(s)
- Mengjie Zhang
- Chengdu Institute of BiologyChinese Academy of SciencesChengduChina,College of Life SciencesNanjing Normal UniversityNanjingChina
| | - Sarah Gaughan
- Department of BiologyUniversity of Nebraska at OmahaOmahaNebraska
| | - Qing Chang
- College of Life SciencesNanjing Normal UniversityNanjingChina
| | - Hua Chen
- Shanghai Biozeron Bioinformatics CenterShanghaiChina
| | - Guoqing Lu
- Department of BiologyUniversity of Nebraska at OmahaOmahaNebraska
| | - Xungang Wang
- Chengdu Institute of BiologyChinese Academy of SciencesChengduChina
| | - Liangliang Xu
- Chengdu Institute of BiologyChinese Academy of SciencesChengduChina,College of Life SciencesNanjing Normal UniversityNanjingChina
| | - Lifeng Zhu
- College of Life SciencesNanjing Normal UniversityNanjingChina,Department of BiologyUniversity of Nebraska at OmahaOmahaNebraska
| | - Jianping Jiang
- Chengdu Institute of BiologyChinese Academy of SciencesChengduChina
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20
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Mutnale MC, Anand S, Eluvathingal LM, Roy JK, Reddy GS, Vasudevan K. Enzootic frog pathogen Batrachochytrium dendrobatidis in Asian tropics reveals high ITS haplotype diversity and low prevalence. Sci Rep 2018; 8:10125. [PMID: 29973607 PMCID: PMC6031667 DOI: 10.1038/s41598-018-28304-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 06/20/2018] [Indexed: 11/09/2022] Open
Abstract
Emerging Infectious Diseases (EIDs) are a major threat to wildlife and a key player in the declining amphibian populations worldwide. One such EID is chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd), a fungal pathogen. Aetiology of Bd infection is poorly known from tropical frogs in Asian biodiversity hotspots. Surveys were carried out in four biodiversity hotspots to ascertain the status of Bd fungus. We collected a total of 1870 swab samples from frogs representing 32 genera and 111 species. Nested PCRs revealed low prevalence (8.4%) and high Bd haplotype richness was revealed after sequencing. We document 57 Bd Internal Transcribed Spacer region (ITS) haplotypes, of which 46 were unique to the global database. Bd ITS region showed indels at the Taqman binding site and qPCR reverse primer binding site, suggesting qPCR is unsuitable for diagnosis in Asian Bd coldspots. Our median-joining network and Bayesian tree analyses reveal that the Asian haplotypes, with the exception of Korea, formed a separate clade along with pandemic BdGPL (Bd Global Panzootic Lineage) haplotype. We hypothesise that the frog populations in Asian tropics might harbour several endemic strains of Bd, and the high levels of diversity and uniqueness of Bd haplotypes in the region, probably resulted from historical host-pathogen co-evolution.
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Affiliation(s)
- Milind C Mutnale
- CSIR-Centre for Cellular and Molecular Biology, Laboratory for the Conservation of Endangered Species, Hyderabad, Telangana, India
| | - Sachin Anand
- CSIR-Centre for Cellular and Molecular Biology, Laboratory for the Conservation of Endangered Species, Hyderabad, Telangana, India
| | | | - Jayanta K Roy
- Department of Life Science and Bioinformatics, Assam University, Diphu Campus, Karbi Anglong, Assam, 782460, India
| | - Gundlapally S Reddy
- CSIR-Centre for Cellular and Molecular Biology, Laboratory for the Conservation of Endangered Species, Hyderabad, Telangana, India
| | - Karthikeyan Vasudevan
- CSIR-Centre for Cellular and Molecular Biology, Laboratory for the Conservation of Endangered Species, Hyderabad, Telangana, India.
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Hybrids of amphibian chytrid show high virulence in native hosts. Sci Rep 2018; 8:9600. [PMID: 29941894 PMCID: PMC6018099 DOI: 10.1038/s41598-018-27828-w] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2018] [Accepted: 06/06/2018] [Indexed: 01/05/2023] Open
Abstract
Hybridization of parasites can generate new genotypes with high virulence. The fungal amphibian parasite Batrachochytrium dendrobatidis (Bd) hybridizes in Brazil’s Atlantic Forest, a biodiversity hotspot where amphibian declines have been linked to Bd, but the virulence of hybrid genotypes in native hosts has never been tested. We compared the virulence (measured as host mortality and infection burden) of hybrid Bd genotypes to the parental lineages, the putatively hypovirulent lineage Bd-Brazil and the hypervirulent Global Pandemic Lineage (Bd-GPL), in a panel of native Brazilian hosts. In Brachycephalus ephippium, the hybrid exceeded the virulence (host mortality) of both parents, suggesting that novelty arising from hybridization of Bd is a conservation concern. In Ischnocnema parva, host mortality in the hybrid treatment was intermediate between the parent treatments, suggesting that this species is more vulnerable to the aggressive phenotypes associated with Bd-GPL. Dendropsophus minutus showed low overall mortality, but infection burdens were higher in frogs treated with hybrid and Bd-GPL genotypes than with Bd-Brazil genotypes. Our experiment suggests that Bd hybrids have the potential to increase disease risk in native hosts. Continued surveillance is needed to track potential spread of hybrid genotypes and detect future genomic shifts in this dynamic disease system.
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O'Hanlon SJ, Rieux A, Farrer RA, Rosa GM, Waldman B, Bataille A, Kosch TA, Murray KA, Brankovics B, Fumagalli M, Martin MD, Wales N, Alvarado-Rybak M, Bates KA, Berger L, Böll S, Brookes L, Clare F, Courtois EA, Cunningham AA, Doherty-Bone TM, Ghosh P, Gower DJ, Hintz WE, Höglund J, Jenkinson TS, Lin CF, Laurila A, Loyau A, Martel A, Meurling S, Miaud C, Minting P, Pasmans F, Schmeller DS, Schmidt BR, Shelton JMG, Skerratt LF, Smith F, Soto-Azat C, Spagnoletti M, Tessa G, Toledo LF, Valenzuela-Sánchez A, Verster R, Vörös J, Webb RJ, Wierzbicki C, Wombwell E, Zamudio KR, Aanensen DM, James TY, Gilbert MTP, Weldon C, Bosch J, Balloux F, Garner TWJ, Fisher MC. Recent Asian origin of chytrid fungi causing global amphibian declines. Science 2018; 360:621-627. [PMID: 29748278 PMCID: PMC6311102 DOI: 10.1126/science.aar1965] [Citation(s) in RCA: 288] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Accepted: 03/29/2018] [Indexed: 12/14/2022]
Abstract
Globalized infectious diseases are causing species declines worldwide, but their source often remains elusive. We used whole-genome sequencing to solve the spatiotemporal origins of the most devastating panzootic to date, caused by the fungus Batrachochytrium dendrobatidis, a proximate driver of global amphibian declines. We traced the source of B. dendrobatidis to the Korean peninsula, where one lineage, BdASIA-1, exhibits the genetic hallmarks of an ancestral population that seeded the panzootic. We date the emergence of this pathogen to the early 20th century, coinciding with the global expansion of commercial trade in amphibians, and we show that intercontinental transmission is ongoing. Our findings point to East Asia as a geographic hotspot for B. dendrobatidis biodiversity and the original source of these lineages that now parasitize amphibians worldwide.
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Affiliation(s)
- Simon J O'Hanlon
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK.
- Institute of Zoology, Regent's Park, London NW1 4RY, UK
| | - Adrien Rieux
- CIRAD, UMR PVBMT, 97410 St. Pierre, Reunion, France
| | - Rhys A Farrer
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Gonçalo M Rosa
- Institute of Zoology, Regent's Park, London NW1 4RY, UK
- Department of Biology, University of Nevada, Reno, NV 89557, USA
- Centre for Ecology, Evolution and Environmental Changes (CE3C), Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal
| | - Bruce Waldman
- Laboratory of Behavioral and Population Ecology, School of Biological Sciences, Seoul National University, Seoul 08826, South Korea
| | - Arnaud Bataille
- Laboratory of Behavioral and Population Ecology, School of Biological Sciences, Seoul National University, Seoul 08826, South Korea
- CIRAD, UMR ASTRE, F-34398 Montpellier, France
| | - Tiffany A Kosch
- Laboratory of Behavioral and Population Ecology, School of Biological Sciences, Seoul National University, Seoul 08826, South Korea
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland 4811, Australia
| | - Kris A Murray
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Balázs Brankovics
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584CT Utrecht, Netherlands
- Institute of Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands
| | - Matteo Fumagalli
- Department of Life Sciences, Silwood Park Campus, Imperial College London, Ascot, UK
- UCL Genetics Institute, University College London, London WC1E 6BT, UK
| | - Michael D Martin
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU), Erling Skakkes gate 49, NO-7012 Trondheim, Norway
- Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen, Denmark
| | - Nathan Wales
- Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen, Denmark
| | - Mario Alvarado-Rybak
- Centro de Investigación para la Sustentabilidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Republica 440, Santiago, Chile
| | - Kieran A Bates
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK
- Institute of Zoology, Regent's Park, London NW1 4RY, UK
| | - Lee Berger
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland 4811, Australia
| | - Susanne Böll
- Agency for Population Ecology and Nature Conservancy, Gerbrunn, Germany
| | - Lola Brookes
- Institute of Zoology, Regent's Park, London NW1 4RY, UK
| | - Frances Clare
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK
- Institute of Zoology, Regent's Park, London NW1 4RY, UK
| | - Elodie A Courtois
- Laboratoire Ecologie, Évolution, Interactions des Systèmes Amazoniens (LEEISA), Université de Guyane, CNRS, IFREMER, 97300 Cayenne, French Guiana
| | | | | | - Pria Ghosh
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK
- Unit for Environmental Sciences and Management, Private Bag x6001, North-West University, Potchefstroom 2520, South Africa
| | - David J Gower
- Life Sciences, Natural History Museum, London SW7 5BD, UK
| | - William E Hintz
- Biology Department, University of Victoria, Victoria, BC V8W 3N5, Canada
| | - Jacob Höglund
- Department of Ecology and Genetics, EBC, Uppsala University, Norbyv. 18D, SE-75236, Uppsala, Sweden
| | - Thomas S Jenkinson
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Chun-Fu Lin
- Zoology Division, Endemic Species Research Institute, 1 Ming-shen East Road, Jiji, Nantou 552, Taiwan
| | - Anssi Laurila
- Department of Ecology and Genetics, EBC, Uppsala University, Norbyv. 18D, SE-75236, Uppsala, Sweden
| | - Adeline Loyau
- Department of Conservation Biology, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany
- EcoLab, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
| | - Sara Meurling
- Department of Ecology and Genetics, EBC, Uppsala University, Norbyv. 18D, SE-75236, Uppsala, Sweden
| | - Claude Miaud
- PSL Research University, CEFE UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, Montpellier, France
| | - Pete Minting
- Amphibian and Reptile Conservation (ARC) Trust, Boscombe, Bournemouth, Dorset BH1 4AP, UK
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, B-9820 Merelbeke, Belgium
| | - Dirk S Schmeller
- Department of Conservation Biology, Helmholtz Centre for Environmental Research-UFZ, 04318 Leipzig, Germany
- EcoLab, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France
| | - Benedikt R Schmidt
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, 8057 Zurich, Switzerland, and Info Fauna Karch, UniMail-Bâtiment G, Bellevaux 51, 2000 Neuchâtel, Switzerland
| | - Jennifer M G Shelton
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Lee F Skerratt
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland 4811, Australia
| | - Freya Smith
- Institute of Zoology, Regent's Park, London NW1 4RY, UK
- National Wildlife Management Centre, APHA, Woodchester Park, Gloucestershire GL10 3UJ, UK
| | - Claudio Soto-Azat
- Centro de Investigación para la Sustentabilidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Republica 440, Santiago, Chile
| | | | - Giulia Tessa
- Non-profit Association Zirichiltaggi-Sardinia Wildlife Conservation, Strada Vicinale Filigheddu 62/C, I-07100 Sassari, Italy
| | - Luís Felipe Toledo
- Laboratório de História Natural de Anfíbios Brasileiros (LaHNAB), Departamento de Biologia Animal, Instituto de Biologia, Unicamp, Campinas, Brazil
| | - Andrés Valenzuela-Sánchez
- Centro de Investigación para la Sustentabilidad, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Republica 440, Santiago, Chile
- ONG Ranita de Darwin, Nataniel Cox 152, Santiago, Chile
| | - Ruhan Verster
- Unit for Environmental Sciences and Management, Private Bag x6001, North-West University, Potchefstroom 2520, South Africa
| | - Judit Vörös
- Collection of Amphibians and Reptiles, Department of Zoology, Hungarian Natural History Museum, Budapest, Baross u. 13., 1088, Hungary
| | - Rebecca J Webb
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland 4811, Australia
| | - Claudia Wierzbicki
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Emma Wombwell
- Institute of Zoology, Regent's Park, London NW1 4RY, UK
| | - Kelly R Zamudio
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY 14853, USA
| | - David M Aanensen
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK
- Centre for Genomic Pathogen Surveillance, Wellcome Genome Campus, Cambridgeshire, UK
| | - Timothy Y James
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - M Thomas P Gilbert
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU), Erling Skakkes gate 49, NO-7012 Trondheim, Norway
- Centre for GeoGenetics, Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, 1350 Copenhagen, Denmark
| | - Ché Weldon
- Unit for Environmental Sciences and Management, Private Bag x6001, North-West University, Potchefstroom 2520, South Africa
| | - Jaime Bosch
- Museo Nacional de Ciencias Naturales, CSIC c/ Jose Gutierrez Abascal 2, 28006 Madrid, Spain
| | - François Balloux
- UCL Genetics Institute, University College London, London WC1E 6BT, UK
| | - Trenton W J Garner
- Institute of Zoology, Regent's Park, London NW1 4RY, UK
- Unit for Environmental Sciences and Management, Private Bag x6001, North-West University, Potchefstroom 2520, South Africa
- Non-profit Association Zirichiltaggi-Sardinia Wildlife Conservation, Strada Vicinale Filigheddu 62/C, I-07100 Sassari, Italy
| | - Matthew C Fisher
- Department of Infectious Disease Epidemiology and MRC Centre for Global Infectious Disease Analysis, School of Public Health, Imperial College London, London W2 1PG, UK.
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Bataille A, Lee-Cruz L, Tripathi B, Waldman B. Skin Bacterial Community Reorganization Following Metamorphosis of the Fire-Bellied Toad (Bombina orientalis). MICROBIAL ECOLOGY 2018; 75:505-514. [PMID: 28725944 DOI: 10.1007/s00248-017-1034-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 07/04/2017] [Indexed: 06/07/2023]
Abstract
In organisms with complex life histories, dramatic changes in microbial community structure may occur with host development and immune system maturation. Amphibian host susceptibility to diseases such as chytridiomycosis may be affected by the reorganization of skin microbial community structure that occurs during metamorphosis. We tracked changes in the bacterial communities inhabiting skin of Korean fire-bellied toads (Bombina orientalis) that we infected as tadpoles with different strains of Batrachochytrium dendrobatidis (Bd), the pathogenic fungus that causes chytridiomycosis. We found that B. orientalis undergoes a major change in skin bacterial community composition between 5 and 15 days following metamorphosis. Richness indices and phylogenetic diversity measures began to diverge earlier, between aquatic and terrestrial stages. Our results further reveal differences in skin bacterial community composition among infection groups, suggesting that the effect of Bd infection on skin microbiome composition may differ by Bd strain. Additional studies are needed to further investigate the structural and temporal dynamics of microbiome shifts during metamorphosis in wild and captive amphibian populations. Analyses of the ontogeny of microbiome shifts may contribute to an understanding of why amphibians vary in their susceptibility to chytridiomycosis.
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Affiliation(s)
- Arnaud Bataille
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
- CIRAD, UMR ASTRE, Montpellier, France
| | - Larisa Lee-Cruz
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Binu Tripathi
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea
| | - Bruce Waldman
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, South Korea.
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24
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Liu X, Wang S, Ke Z, Cheng C, Wang Y, Zhang F, Xu F, Li X, Gao X, Jin C, Zhu W, Yan S, Li Y. More invaders do not result in heavier impacts: The effects of non-native bullfrogs on native anurans are mitigated by high densities of non-native crayfish. J Anim Ecol 2018; 87:850-862. [DOI: 10.1111/1365-2656.12793] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 11/28/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Xuan Liu
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
| | - Supen Wang
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
| | - Zunwei Ke
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
- Department of Biology, Chemistry and Environmental Engineering; Hanjiang Normal University; Shiyan China
| | - Chaoyuan Cheng
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
| | - Yihua Wang
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
| | - Fang Zhang
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
- College of Life Sciences; Anhui Normal University; Wuhu China
| | - Feng Xu
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
- Key Laboratory of Biogeography and Bioresources in Arid Land; Xinjiang Institute of Ecology and Geography; Chinese Academy of Sciences; Urumqi China
| | - Xianping Li
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
| | - Xu Gao
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
| | - Changnan Jin
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
- Chinese National Geography; Institute of Geographic Science and Nature Resources Research; Chinese Academy of Sciences; Beijing China
| | - Wei Zhu
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
| | - Shaofei Yan
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
- University of Chinese Academy of Sciences; Beijing China
- School of Resources and Environmental Engineering; Anhui University; Hefei China
| | - Yiming Li
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; Chinese Academy of Sciences; Beijing China
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25
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Wang S, Liu C, Wilson AB, Zhao N, Li X, Zhu W, Gao X, Liu X, Li Y. Pathogen richness and abundance predict patterns of adaptive major histocompatibility complex variation in insular amphibians. Mol Ecol 2017; 26:4671-4685. [PMID: 28734069 DOI: 10.1111/mec.14242] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2016] [Revised: 06/01/2017] [Accepted: 06/19/2017] [Indexed: 12/26/2022]
Abstract
The identification of the factors responsible for genetic variation and differentiation at adaptive loci can provide important insights into the evolutionary process and is crucial for the effective management of threatened species. We studied the impact of environmental viral richness and abundance on functional diversity and differentiation of the MHC class Ia locus in populations of the black-spotted pond frog (Pelophylax nigromaculatus), an IUCN-listed species, on 24 land-bridge islands of the Zhoushan Archipelago and three nearby mainland sites. We found a high proportion of private MHC alleles in mainland and insular populations, corresponding to 32 distinct functional supertypes, and strong positive selection on MHC antigen-binding sites in all populations. Viral pathogen diversity and abundance were reduced at island sites relative to the mainland, and islands housed distinctive viral communities. Standardized MHC diversity at island sites exceeded that found at neutral microsatellites, and the representation of key functional supertypes was positively correlated with the abundance of specific viruses in the environment (Frog virus 3 and Ambystoma tigrinum virus). These results indicate that pathogen-driven diversifying selection can play an important role in maintaining functionally important MHC variation following island isolation, highlighting the importance of considering functionally important genetic variation and host-pathogen associations in conservation planning and management.
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Affiliation(s)
- Supen Wang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Conghui Liu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Anthony B Wilson
- Department of Biology, Brooklyn College and The Graduate Center, City University of New York, Brooklyn, NY, USA
| | - Na Zhao
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xianping Li
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Wei Zhu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Xu Gao
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Xuan Liu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Yiming Li
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,University of Chinese Academy of Sciences, Beijing, China
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26
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Byrne AQ, Rothstein AP, Poorten TJ, Erens J, Settles ML, Rosenblum EB. Unlocking the story in the swab: A new genotyping assay for the amphibian chytrid fungus
Batrachochytrium dendrobatidis. Mol Ecol Resour 2017; 17:1283-1292. [DOI: 10.1111/1755-0998.12675] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 12/26/2016] [Accepted: 03/15/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Allison Q. Byrne
- Department of Environmental Science Policy and Management University of California, Berkeley Berkeley CA USA
| | - Andrew P. Rothstein
- Department of Environmental Science Policy and Management University of California, Berkeley Berkeley CA USA
| | - Thomas J. Poorten
- Department of Environmental Science Policy and Management University of California, Berkeley Berkeley CA USA
| | - Jesse Erens
- Department of Environmental Science Policy and Management University of California, Berkeley Berkeley CA USA
- Wageningen University Wageningen The Netherlands
| | | | - Erica Bree Rosenblum
- Department of Environmental Science Policy and Management University of California, Berkeley Berkeley CA USA
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Batrachochytrium salamandrivorans is the predominant chytrid fungus in Vietnamese salamanders. Sci Rep 2017; 7:44443. [PMID: 28287614 PMCID: PMC5347381 DOI: 10.1038/srep44443] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 02/08/2017] [Indexed: 11/08/2022] Open
Abstract
The amphibian chytrid fungi, Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), pose a major threat to amphibian biodiversity. Recent evidence suggests Southeast Asia as a potential cradle for both fungi, which likely resulted in widespread host-pathogen co-existence. We sampled 583 salamanders from 8 species across Vietnam in 55 locations for Bsal and Bd, determined scaled mass index as a proxy for fitness and collected environmental data. Bsal was found within 14 of the 55 habitats (2 of which it was detected in 2013), in 5 salamandrid species, with a prevalence of 2.92%. The globalized pandemic lineage of Bd was found within one pond on one species with a prevalence of 0.69%. Combined with a complete lack of correlation between infection and individual body condition and absence of indication of associated disease, this suggests low level pathogen endemism and Bsal and Bd co-existence with Vietnamese salamandrid populations. Bsal was more widespread than Bd, and occurs at temperatures higher than tolerated by the type strain, suggesting a wider thermal niche than currently known. Therefore, this study provides support for the hypothesis that these chytrid fungi may be endemic to Asia and that species within this region may act as a disease reservoir.
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28
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Affiliation(s)
- Alice C. Hughes
- Centre for Integrative Conservation; Xishuangbanna Tropical Botanical Garden; Chinese Academy of Sciences; Menglun Jinghong 666303 China
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29
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Insights From Genomics Into Spatial and Temporal Variation in Batrachochytrium dendrobatidis. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2016. [PMID: 27571698 DOI: 10.1016/bs.pmbts.2016.05.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
Advances in genetics and genomics have provided new tools for the study of emerging infectious diseases. Researchers can now move quickly from simple hypotheses to complex explanations for pathogen origin, spread, and mechanisms of virulence. Here we focus on the application of genomics to understanding the biology of the fungal pathogen Batrachochytrium dendrobatidis (Bd), a novel and deadly pathogen of amphibians. We provide a brief history of the system, then focus on key insights into Bd variation garnered from genomics approaches, and finally, highlight new frontiers for future discoveries. Genomic tools have revealed unexpected complexity and variation in the Bd system suggesting that the history and biology of emerging pathogens may not be as simple as they initially seem.
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30
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Zhu W, Fan L, Soto-Azat C, Yan S, Gao X, Liu X, Wang S, Liu C, Yang X, Li Y. Filling a gap in the distribution of Batrachochytrium dendrobatidis: evidence in amphibians from northern China. DISEASES OF AQUATIC ORGANISMS 2016; 118:259-265. [PMID: 27025313 DOI: 10.3354/dao02975] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) has been recognized as a major driver of amphibian declines worldwide. Central and northern Asia remain as the greatest gap in the knowledge of the global distribution of Bd. In China, Bd has recently been recorded from south and central regions, but areas in the north remain poorly surveyed. In addition, a recent increase in amphibian farming and trade has put this region at high risk for Bd introduction. To investigate this, we collected a total of 1284 non-invasive skin swabs from wild and captive anurans and caudates, including free-ranging, farmed, ornamental, and museum-preserved amphibians. Bd was detected at low prevalence (1.1%, 12 of 1073) in live wild amphibians, representing the first report of Bd infecting anurans from remote areas of northwestern China. We were unable to obtain evidence of the historical presence of Bd from museum amphibians (n = 72). Alarmingly, Bd was not detected in wild amphibians from the provinces of northeastern China (>700 individuals tested), but was widely present (15.1%, 21 of 139) in amphibians traded in this region. We suggest that urgent implementation of measures is required to reduce the possibility of further spread or inadvertent introduction of Bd to China. It is unknown whether Bd in northern China belongs to endemic and/or exotic genotypes, and this should be the focus of future research.
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Affiliation(s)
- Wei Zhu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
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31
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Emergent Vegetation Coverage and Human Activities Influence Oviposition Microhabitat Selection by Invasive Bullfrogs (Lithobates catesbeianus) in Southwestern China. J HERPETOL 2016. [DOI: 10.1670/14-151] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Bataille A, Lee-Cruz L, Tripathi B, Kim H, Waldman B. Microbiome Variation Across Amphibian Skin Regions: Implications for Chytridiomycosis Mitigation Efforts. MICROBIAL ECOLOGY 2016; 71:221-32. [PMID: 26271741 DOI: 10.1007/s00248-015-0653-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Accepted: 07/16/2015] [Indexed: 05/20/2023]
Abstract
Cutaneous bacteria may play an important role in the resistance of amphibians to the pathogenic fungus Batrachochytrium dendrobatidis (Bd). Microbial communities resident on hosts' skin show topographical diversity mapping to skin features, as demonstrated by studies of the human microbiome. We examined skin microbiomes of wild and captive fire-bellied toads (Bombina orientalis) for differences across their body surface. We found that bacterial communities differed between ventral and dorsal skin. Wild toads showed slightly higher bacterial richness and diversity in the dorsal compared to the ventral region. On the other hand, captive toads hosted a higher richness and diversity of bacteria on their ventral than their dorsal skin. Microbial community composition and relative abundance of major bacterial taxonomic groups also differed between ventral and dorsal skin in all populations. Furthermore, microbiome diversity patterns varied as a function of their Bd infection status in wild toads. Bacterial richness and diversity was greater, and microbial community structure more complex, in wild than captive toads. The results suggest that bacterial community structure is influenced by microhabitats associated with skin regions. These local communities may be differentially modified when interacting with environmental bacteria and Bd. A better understanding of microbiome variation across skin regions will be needed to assess how the skin microbiota affects the abilities of amphibian hosts to resist Bd infection, especially in captive breeding programs.
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Affiliation(s)
- Arnaud Bataille
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747, South Korea
| | - Larisa Lee-Cruz
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747, South Korea
| | - Binu Tripathi
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747, South Korea
| | | | - Bruce Waldman
- School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747, South Korea.
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Van Rooij P, Martel A, Haesebrouck F, Pasmans F. Amphibian chytridiomycosis: a review with focus on fungus-host interactions. Vet Res 2015; 46:137. [PMID: 26607488 PMCID: PMC4660679 DOI: 10.1186/s13567-015-0266-0] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 10/05/2015] [Indexed: 01/30/2023] Open
Abstract
Amphibian declines and extinctions are emblematic for the current sixth mass extinction event. Infectious drivers of these declines include the recently emerged fungal pathogens Batrachochytrium dendrobatidis and Batrachochytrium salamandrivorans (Chytridiomycota). The skin disease caused by these fungi is named chytridiomycosis and affects the vital function of amphibian skin. Not all amphibians respond equally to infection and host responses might range from resistant, over tolerant to susceptible. The clinical outcome of infection is highly dependent on the amphibian host, the fungal virulence and environmental determinants. B. dendrobatidis infects the skin of a large range of anurans, urodeles and caecilians, whereas to date the host range of B. salamandrivorans seems limited to urodeles. So far, the epidemic of B. dendrobatidis is mainly limited to Australian, neotropical, South European and West American amphibians, while for B. salamandrivorans it is limited to European salamanders. Other striking differences between both fungi include gross pathology and thermal preferences. With this review we aim to provide the reader with a state-of-the art of host-pathogen interactions for both fungi, in which new data pertaining to the interaction of B. dendrobatidis and B. salamandrivorans with the host’s skin are integrated. Furthermore, we pinpoint areas in which more detailed studies are necessary or which have not received the attention they merit.
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Affiliation(s)
- Pascale Van Rooij
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - An Martel
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Freddy Haesebrouck
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
| | - Frank Pasmans
- Laboratory of Veterinary Bacteriology and Mycology, Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium.
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Gao X, Jin C, Camargo A, Li Y. Allocation trade-off under climate warming in experimental amphibian populations. PeerJ 2015; 3:e1326. [PMID: 26500832 PMCID: PMC4614843 DOI: 10.7717/peerj.1326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 09/24/2015] [Indexed: 11/24/2022] Open
Abstract
Climate change could either directly or indirectly cause population declines via altered temperature, rainfall regimes, food availability or phenological responses. However few studies have focused on allocation trade-offs between growth and reproduction under marginal resources, such as food scarce that may be caused by climate warming. Such critical changes may have an unpredicted impact on amphibian life-history parameters and even population dynamics. Here, we report an allocation strategy of adult anuran individuals involving a reproductive stage under experimental warming. Using outdoor mesocosm experiments we simulated a warming scenario likely to occur at the end of this century. We examined the effects of temperature (ambient vs. pre-/post-hibernation warming) and food availability (normal vs. low) on reproduction and growth parameters of pond frogs (Pelophylax nigromaculatus). We found that temperature was the major factor influencing reproductive time of female pond frogs, which showed a significant advancing under post-hibernation warming treatment. While feeding rate was the major factor influencing reproductive status of females, clutch size, and variation of body size for females, showed significant positive correlations between feeding rate and reproductive status, clutch size, or variation of body size. Our results suggested that reproduction and body size of amphibians might be modulated by climate warming or food availability variation. We believe this study provides some new evidence on allocation strategies suggesting that amphibians could adjust their reproductive output to cope with climate warming.
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Affiliation(s)
- Xu Gao
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China ; University of Chinese Academy of Sciences , Beijing , China
| | - Changnan Jin
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China ; University of Chinese Academy of Sciences , Beijing , China ; Chinese National Geography Magazine , Beijing , China
| | - Arley Camargo
- Centro Universitario de Rivera, Universidad de la República , Rivera , Uruguay
| | - Yiming Li
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences , Beijing , China
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Rosenstock N, Toranza C, Brazeiro A. Climate and land-use changes effects on the distribution of a regional endemism: Melanophryniscus sanmartini (Amphibia, Bufonidae). IHERINGIA. SERIE ZOOLOGIA 2015. [DOI: 10.1590/1678-476620151052209216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
ABSTRACT Amphibians are the most threatened vertebrate group according to the IUCN. Land-use and land cover change (LULCC) and climate change (CC) are two of the main factors related to declining amphibian populations. Given the vulnerability of threatened and rare species, the study of their response to these impacts is a conservation priority. The aim of this work was to analyze the combined impact of LULCC and CC on the regionally endemic species Melanophryniscus sanmartini Klappenbach, 1968. This species is currently categorized as near threatened by the IUCN, and previous studies suggest negative effects of projected changes in climate. Using maximum entropy methods we modeled the effects of CC on the current and mid-century distribution of M. sanmartini under two IPCC scenarios - A2 (severe) and B2 (moderate). The effects of LULCC were studied by superimposing the potential distribution with current land use, while future distribution models were evaluated under the scenario of maximum expansion of soybean and afforestation in Uruguay. The results suggest that M. sanmartini is distributed in eastern Uruguay and the south of Brazil, mainly related to hilly and grasslands systems. Currently more than 10% of this species' distribution is superimposed by agricultural crops and exotic forest plantations. Contrasting with a recent modelling study our models suggest an expansion of the distribution of M. sanmartini by mid-century under both climate scenarios. However, despite the rise in climatically suitable areas for the species in the future, LULCC projections indicate that the proportion of modified habitats will occupy up to 25% of the distribution of M. sanmartini. Future change in climate conditions could represent an opportunity for M. sanmartini, but management measures are needed to mitigate the effects of habitat modification in order to ensure its survival and allow the eventual expansion of its distribution.
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Early 1900 s detection of Batrachochytrium dendrobatidis in Korean amphibians. PLoS One 2015; 10:e0115656. [PMID: 25738656 PMCID: PMC4349589 DOI: 10.1371/journal.pone.0115656] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 11/12/2014] [Indexed: 11/30/2022] Open
Abstract
The pathogenic fungus Batrachochytrium dendrobatidis (Bd) is a major conservation concern because of its role in decimating amphibian populations worldwide. We used quantitative PCR to screen 244 museum specimens from the Korean Peninsula, collected between 1911 and 2004, for the presence of Bd to gain insight into its history in Asia. Three specimens of Rugosa emeljanovi (previously Rana or Glandirana rugosa), collected in 1911 from Wonsan, North Korea, tested positive for Bd. Histology of these positive specimens revealed mild hyperkeratosis – a non-specific host response commonly found in Bd-infected frogs – but no Bd zoospores or zoosporangia. Our results indicate that Bd was present in Korea more than 100 years ago, consistent with hypotheses suggesting that Korean amphibians may be infected by endemic Asian Bd strains.
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Bletz MC, Rosa GM, Andreone F, Courtois EA, Schmeller DS, Rabibisoa NHC, Rabemananjara FCE, Raharivololoniaina L, Vences M, Weldon C, Edmonds D, Raxworthy CJ, Harris RN, Fisher MC, Crottini A. Widespread presence of the pathogenic fungus Batrachochytrium dendrobatidis in wild amphibian communities in Madagascar. Sci Rep 2015; 5:8633. [PMID: 25719857 PMCID: PMC4341422 DOI: 10.1038/srep08633] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 01/12/2015] [Indexed: 01/15/2023] Open
Abstract
Amphibian chytridiomycosis, an emerging infectious disease caused by the fungus Batrachochytrium dendrobatidis (Bd), has been a significant driver of amphibian declines. While globally widespread, Bd had not yet been reported from within Madagascar. We document surveys conducted across the country between 2005 and 2014, showing Bd's first record in 2010. Subsequently, Bd was detected in multiple areas, with prevalence reaching up to 100%. Detection of Bd appears to be associated with mid to high elevation sites and to have a seasonal pattern, with greater detectability during the dry season. Lineage-based PCR was performed on a subset of samples. While some did not amplify with any lineage probe, when a positive signal was observed, samples were most similar to the Global Panzootic Lineage (BdGPL). These results may suggest that Bd arrived recently, but do not exclude the existence of a previously undetected endemic Bd genotype. Representatives of all native anuran families have tested Bd-positive, and exposure trials confirm infection by Bd is possible. Bd's presence could pose significant threats to Madagascar's unique "megadiverse" amphibians.
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Affiliation(s)
- Molly C Bletz
- 1] Department of Biology, James Madison University, Harrisonburg, VA 22807, USA [2] Technische Universität Braunschweig, Division of Evolutionary Biology, Zoological Institute, Mendelssohnstr. 4, 38106 Braunschweig, Germany
| | - Gonçalo M Rosa
- 1] Durrell Institute of Conservation and Ecology, School of Anthropology and Conservation, University of Kent, Canterbury, Kent CT2 7NR, UK [2] Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK [3] Centre for Ecology, Evolution and Environmental Changes (CE3C), Faculdade de Ciências da Universidade de Lisboa, Bloco 2, Piso 5, Campo Grande, 1749-016 Lisbon, Portugal
| | - Franco Andreone
- 1] Museo Regionale di Scienze Naturali, Via G. Giolitti, 36, I-10123, Torino, Italy [2] IUCN SSC Amphibian Specialist Group-Madagascar, 101 Antananarivo, Madagascar
| | - Elodie A Courtois
- 1] CNRS-Guyane, USR 3456, 2 avenue Gustave Charlery, 97300 Cayenne, Guyane Française [2] Station d'écologie expérimentale du CNRS à Moulis, USR 2936, 2 route du CNRS, 09200 Moulis, France
| | - Dirk S Schmeller
- 1] UFZ - Helmholtz Centre for Environmental Research, Department of Conservation Biology, Permoserstr. 15, 04318 Leipzig, Germany [2] EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), CNRS/Université de Toulouse; UPS, INPT; 118 route de Narbonne, 31062 Toulouse, France
| | - Nirhy H C Rabibisoa
- 1] IUCN SSC Amphibian Specialist Group-Madagascar, 101 Antananarivo, Madagascar [2] Département de Biologie Animale et Ecologie, Faculté des Sciences, University of Mahajanga, Ambondrona, B.P. 652, Mahajanga 401, Madagascar
| | - Falitiana C E Rabemananjara
- 1] IUCN SSC Amphibian Specialist Group-Madagascar, 101 Antananarivo, Madagascar [2] University of Antananarivo, BP 906, Antananarivo 101, Antananarivo, Madagascar
| | | | - Miguel Vences
- Technische Universität Braunschweig, Division of Evolutionary Biology, Zoological Institute, Mendelssohnstr. 4, 38106 Braunschweig, Germany
| | - Ché Weldon
- Unit for Environmental Sciences and Management, North-West University, Private Bag X6001, Potchefstroom 2520, South Africa
| | - Devin Edmonds
- Association Mitsinjo, Lot 104 A Andasibe Gare, Andasibe 514, Madagascar
| | - Christopher J Raxworthy
- Department of Herpetology, American Museum of Natural History, Central Park West at 79th St. New York, NY 10024, USA
| | - Reid N Harris
- Department of Biology, James Madison University, Harrisonburg, VA 22807, USA
| | - Matthew C Fisher
- Department of Infectious Disease Epidemiology, Imperial College London, W2 1PG, UK
| | - Angelica Crottini
- CIBIO Research Centre in Biodiversity and Genetic Resources, InBIO, Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, N° 7, 4485-661 Vairão, Vila do Conde, Portugal
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Tompkins DM, Carver S, Jones ME, Krkošek M, Skerratt LF. Emerging infectious diseases of wildlife: a critical perspective. Trends Parasitol 2015; 31:149-59. [PMID: 25709109 DOI: 10.1016/j.pt.2015.01.007] [Citation(s) in RCA: 176] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 01/07/2015] [Accepted: 01/22/2015] [Indexed: 12/20/2022]
Abstract
We review the literature to distinguish reports of vertebrate wildlife disease emergence with sufficient evidence, enabling a robust assessment of emergence drivers. For potentially emerging agents that cannot be confirmed, sufficient data on prior absence (or a prior difference in disease dynamics) are frequently lacking. Improved surveillance, particularly for neglected host taxa, geographical regions and infectious agents, would enable more effective management should emergence occur. Exposure to domestic sources of infection and human-assisted exposure to wild sources were identified as the two main drivers of emergence across host taxa; the domestic source was primary for fish while the wild source was primary for other taxa. There was generally insufficient evidence for major roles of other hypothesized drivers of emergence.
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Affiliation(s)
| | - Scott Carver
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia
| | - Menna E Jones
- School of Biological Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania 7001, Australia
| | - Martin Krkošek
- Department of Ecology and Evolutionary Biology, University of Toronto, 25 Harbord St, Toronto, ON, M5S 3G5, Canada
| | - Lee F Skerratt
- One Health Research Group, College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, Queensland, Australia
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40
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Bai C, Wang C, Xia J, Sun H, Zhang S, Huang J. Emerging and endemic types of Ostreid herpesvirus 1 were detected in bivalves in China. J Invertebr Pathol 2015; 124:98-106. [DOI: 10.1016/j.jip.2014.11.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 11/17/2014] [Accepted: 11/25/2014] [Indexed: 12/11/2022]
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Swabbing often fails to detect amphibian Chytridiomycosis under conditions of low infection load. PLoS One 2014; 9:e111091. [PMID: 25333363 PMCID: PMC4205094 DOI: 10.1371/journal.pone.0111091] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 09/25/2014] [Indexed: 11/23/2022] Open
Abstract
The pathogenic chytrid fungus, Batrachochytrium dendrobatidis (denoted Bd), causes large-scale epizootics in naïve amphibian populations. Intervention strategies to rapidly respond to Bd incursions require sensitive and accurate diagnostic methods. Chytridiomycosis usually is assessed by quantitative polymerase chain reaction (qPCR) amplification of amphibian skin swabs. Results based on this method, however, sometimes yield inconsistent results on infection status and inaccurate scores of infection intensity. In Asia and other regions where amphibians typically bear low Bd loads, swab results are least reliable. We developed a Bd-sampling method that collects zoospores released by infected subjects into an aquatic medium. Bd DNA is extracted by filters and amplified by nested PCR. Using laboratory colonies and field populations of Bombina orientalis, we compare results with those obtained on the same subjects by qPCR of DNA extracted from swabs. Many subjects, despite being diagnosed as Bd-negative by conventional methods, released Bd zoospores into collection containers and thus must be considered infected. Infection loads determined from filtered water were at least 1000 times higher than those estimated from swabs. Subjects significantly varied in infection load, as they intermittently released zoospores, over a 5-day period. Thus, the method might be used to compare the infectivity of individuals and study the periodicity of zoospore release. Sampling methods based on water filtration can dramatically increase the capacity to accurately diagnose chytridiomycosis and contribute to a better understanding of the interactions between Bd and its hosts.
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42
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Longo AV, Burrowes PA, Zamudio KR. Genomic Studies of Disease-Outcome in Host-Pathogen Dynamics. Integr Comp Biol 2014; 54:427-38. [DOI: 10.1093/icb/icu073] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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43
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Zhu W, Bai C, Wang S, Soto-Azat C, Li X, Liu X, Li Y. Retrospective survey of museum specimens reveals historically widespread presence of Batrachochytrium dendrobatidis in China. ECOHEALTH 2014; 11:241-250. [PMID: 24419667 DOI: 10.1007/s10393-013-0894-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 10/20/2013] [Accepted: 12/12/2013] [Indexed: 06/03/2023]
Abstract
Chytridiomycosis, caused by the chytrid fungus Batrachochytrium dendrobatidis (Bd), has been implicated in amphibian population declines worldwide. However, no amphibian declines or extinctions associated with Bd have been reported in Asia. To investigate the history of this pathogen in China, we examined 1,007 museum-preserved amphibian specimens of 80 species collected between 1933 and 2009. Bd was detected in 60 individuals (6.0%), with the earliest case of Bd infection occurring in one specimen of Bufo gargarizans and two Fejervarya limnocharis, all collected in 1933 from Chongqing, southwest China. Although mainly detected in non-threatened native amphibians, Bd was also found in four endangered species. We report the first evidence of Bd for Taiwan and the first detection of Bd in the critically endangered Chinese giant salamander (Andrias davidianus). Bd appears to have been present at a low rate of infection since at least the 1930s in China, and no significant differences in prevalence were detected between decades or provinces, suggesting that a historical steady endemic relationship between Bd and Chinese amphibians has occurred. Our results add new insights on the global emergence of Bd and suggest that this pathogen has been more widely distributed in the last century than previously believed.
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Affiliation(s)
- Wei Zhu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing, 100101, China
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Tamukai K, Une Y, Tominaga A, Suzuki K, Goka K. Batrachochytrium dendrobatidis prevalence and haplotypes in domestic and imported pet amphibians in Japan. DISEASES OF AQUATIC ORGANISMS 2014; 109:165-175. [PMID: 24991744 DOI: 10.3354/dao02732] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The international trade in amphibians is believed to have increased the spread of Batrachochytrium dendrobatidis (Bd), the fungal pathogen responsible for chytridiomycosis, which has caused a rapid decline in amphibian populations worldwide. We surveyed amphibians imported into Japan and those held in captivity for a long period or bred in Japan to clarify the Bd infection status. Samples were taken from 820 individuals of 109 amphibian species between 2008 and 2011 and were analyzed by a nested-PCR assay. Bd prevalence in imported amphibians was 10.3% (58/561), while it was 6.9% (18/259) in those in private collections and commercially bred amphibians in Japan. We identified the genotypes of this fungus using partial DNA sequences of the internal transcribed spacer (ITS) region. Sequencing of PCR products of all 76 Bd-positive samples revealed 11 haplotypes of the Bd ITS region. Haplotype A (DNA Data Bank of Japan accession number AB435211) was found in 90% (52/58) of imported amphibians. The results show that Bd is currently entering Japan via the international trade in exotic amphibians as pets, suggesting that the trade has indeed played a major role in the spread of Bd.
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Affiliation(s)
- Kenichi Tamukai
- Den-en-chofu Animal Hospital, 2-1-3 Denenchofu, Ota-ku, Tokyo 145-0071, Japan
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45
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First evidence of amphibian chytrid fungus (Batrachochytrium dendrobatidis) and ranavirus in Hong Kong amphibian trade. PLoS One 2014; 9:e90750. [PMID: 24599268 PMCID: PMC3944218 DOI: 10.1371/journal.pone.0090750] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 02/03/2014] [Indexed: 11/19/2022] Open
Abstract
The emerging infectious amphibian diseases caused by amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) and ranaviruses are responsible for global amphibian population declines and extinctions. Although likely to have been spread by a variety of activities, transcontinental dispersal appears closely associated with the international trade in live amphibians. The territory of Hong Kong reports frequent, high volume trade in amphibians, and yet the presence of Bd and ranavirus have not previously been detected in either traded or free-ranging amphibians. In 2012, a prospective surveillance project was conducted to investigate the presence of these pathogens in commercial shipments of live amphibians exported from Hong Kong International Airport. Analysis of skin (Bd) and cloacal (ranavirus) swabs by quantitative PCR detected pathogen presence in 31/265 (11.7%) and in 105/185 (56.8%) of amphibians, respectively. In addition, the water in which animals were transported tested positive for Bd, demonstrating the risk of pathogen pollution by the disposal of untreated wastewater. It is uncertain whether Bd and ranavirus remain contained within Hong Kong's trade sector, or if native amphibians have already been exposed. Rapid response efforts are now urgently needed to determine current pathogen distribution in Hong Kong, evaluate potential trade-associated exposure to free-ranging amphibians, and identify opportunities to prevent disease establishment.
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46
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Rodriguez D, Becker CG, Pupin NC, Haddad CFB, Zamudio KR. Long-term endemism of two highly divergent lineages of the amphibian-killing fungus in the Atlantic Forest of Brazil. Mol Ecol 2014; 23:774-87. [DOI: 10.1111/mec.12615] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Revised: 11/21/2013] [Accepted: 11/23/2013] [Indexed: 11/30/2022]
Affiliation(s)
- D. Rodriguez
- Department of Ecology and Evolutionary Biology; Cornell University; Ithaca NY 14853 USA
- Department of Biology; Texas State University; San Marcos TX 78666 USA
| | - C. G. Becker
- Department of Ecology and Evolutionary Biology; Cornell University; Ithaca NY 14853 USA
| | - N. C. Pupin
- Departamento de Zoologia; Instituto de Biociências; Universidade Estadual Paulista; 13506-900 Rio Claro SP Brazil
| | - C. F. B. Haddad
- Departamento de Zoologia; Instituto de Biociências; Universidade Estadual Paulista; 13506-900 Rio Claro SP Brazil
| | - K. R. Zamudio
- Department of Ecology and Evolutionary Biology; Cornell University; Ithaca NY 14853 USA
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47
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Wang S, Zhu W, Gao X, Li X, Yan S, Liu X, Yang J, Gao Z, Li Y. Population size and time since island isolation determine genetic diversity loss in insular frog populations. Mol Ecol 2014; 23:637-48. [PMID: 24351057 DOI: 10.1111/mec.12634] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2013] [Revised: 12/05/2013] [Accepted: 12/11/2013] [Indexed: 12/01/2022]
Affiliation(s)
- Supen Wang
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; The Chinese Academy of Sciences; 1 Datun Beichen West Road Chaoyang Beijing 100101 China
- University of Chinese Academy of Sciences; 19 Yuquan Road Shijingshan Beijing 100049 China
| | - Wei Zhu
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; The Chinese Academy of Sciences; 1 Datun Beichen West Road Chaoyang Beijing 100101 China
- University of Chinese Academy of Sciences; 19 Yuquan Road Shijingshan Beijing 100049 China
| | - Xu Gao
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; The Chinese Academy of Sciences; 1 Datun Beichen West Road Chaoyang Beijing 100101 China
- University of Chinese Academy of Sciences; 19 Yuquan Road Shijingshan Beijing 100049 China
| | - Xianping Li
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; The Chinese Academy of Sciences; 1 Datun Beichen West Road Chaoyang Beijing 100101 China
- University of Chinese Academy of Sciences; 19 Yuquan Road Shijingshan Beijing 100049 China
| | - Shaofei Yan
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; The Chinese Academy of Sciences; 1 Datun Beichen West Road Chaoyang Beijing 100101 China
- University of Chinese Academy of Sciences; 19 Yuquan Road Shijingshan Beijing 100049 China
| | - Xuan Liu
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; The Chinese Academy of Sciences; 1 Datun Beichen West Road Chaoyang Beijing 100101 China
| | - Ji Yang
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; The Chinese Academy of Sciences; 1 Datun Beichen West Road Chaoyang Beijing 100101 China
| | - Zengxiang Gao
- College of Environmental Science and Engineering; Ocean University of China; 5 Yushan Road Lao Shan Qingdao 266003 China
| | - Yiming Li
- Key Laboratory of Animal Ecology and Conservation Biology; Institute of Zoology; The Chinese Academy of Sciences; 1 Datun Beichen West Road Chaoyang Beijing 100101 China
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48
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Abstract
Pathogenic fungi have substantial effects on global biodiversity, and 2 emerging pathogenic species—the chytridiomycete Batrachochytrium dendrobatidis, which causes chytridiomycosis in amphibians, and the ascomycete Geomyces destructans, which causes white-nose syndrome in hibernating bats—are implicated in the widespread decline of their vertebrate hosts. We synthesized current knowledge for chytridiomycosis and white-nose syndrome regarding disease emergence, environmental reservoirs, life history characteristics of the host, and host–pathogen interactions. We found striking similarities between these aspects of chytridiomycosis and white-nose syndrome, and the research that we review and propose should help guide management of future emerging fungal diseases.
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49
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Dahanukar N, Krutha K, Paingankar MS, Padhye AD, Modak N, Molur S. Endemic Asian chytrid strain infection in threatened and endemic anurans of the Northern Western Ghats, India. PLoS One 2013; 8:e77528. [PMID: 24147018 PMCID: PMC3795670 DOI: 10.1371/journal.pone.0077528] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 09/04/2013] [Indexed: 11/18/2022] Open
Abstract
The Western Ghats of India harbors a rich diversity of amphibians with more than 77% species endemic to this region. At least 42% of the endemic species are threatened due to several anthropogenic stressors. However, information on amphibian diseases and their impacts on amphibian populations in this region are scarce. We report the occurrence of Batrachochytridium dendrobatidis (Bd), an epidermal aquatic fungal pathogen that causes chytridiomycosis in amphibians, from the Western Ghats. In the current study we detected the occurrence of a native Asian Bd strain from three endemic and threatened species of anurans, Bombay Night Frog Nyctibatrachus humayuni, Leith's Leaping Frog Indirana leithii and Bombay Bubble Nest Frog Raorchestes bombayensis, for the first time from the northern Western Ghats of India based on diagnostic nested PCR, quantitative PCR, DNA sequencing and histopathology. While, the Bd infected I. leithii and R. bombayensis did not show any external symptoms, N. humayuni showed lesions on the skin, browning of skin and sloughing. Sequencing of Bd 5.8S ribosomal RNA gene, and the ITS1 and ITS2 regions, revealed that the current Bd strain is related to a haplotype endemic to Asia. Our findings confirm the presence of Bd in northern Western Ghats and the affected amphibians may or may not show detectable clinical symptoms. We suggest that the significance of diseases as potential threat to amphibian populations of the Western Ghats needs to be highlighted from the conservation point of view.
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Affiliation(s)
- Neelesh Dahanukar
- Indian Institute of Science Education and Research (IISER), Pune, Maharashtra, India
- Zoo Outreach Organization (ZOO), Coimbatore, Tamil Nadu, India
| | - Keerthi Krutha
- Wildlife Information Liaison Development (WILD) Society, Coimbatore, Tamil Nadu, India
| | | | - Anand D. Padhye
- Department of Zoology, M.E.S. Abasaheb Garware College, Pune, Maharashtra, India
| | - Nikhil Modak
- Department of Biodiversity, M.E.S. Abasaheb Garware College, Pune, Maharashtra, India
| | - Sanjay Molur
- Zoo Outreach Organization (ZOO), Coimbatore, Tamil Nadu, India
- Wildlife Information Liaison Development (WILD) Society, Coimbatore, Tamil Nadu, India
- Conservation Breeding Specialist Group South Asia (CBSG-SA), Coimbatore, Tamil Nadu, India
- * E-mail:
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50
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Bataille A, Fong JJ, Cha M, Wogan GOU, Baek HJ, Lee H, Min MS, Waldman B. Genetic evidence for a high diversity and wide distribution of endemic strains of the pathogenic chytrid fungus Batrachochytrium dendrobatidis
in wild Asian amphibians. Mol Ecol 2013; 22:4196-4209. [DOI: 10.1111/mec.12385] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 05/09/2013] [Accepted: 05/11/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Arnaud Bataille
- Laboratory of Behavioral and Population Ecology; School of Biological Sciences; Seoul National University; Seoul 151-747 South Korea
| | - Jonathan J. Fong
- Laboratory of Behavioral and Population Ecology; School of Biological Sciences; Seoul National University; Seoul 151-747 South Korea
| | - Moonsuk Cha
- Laboratory of Behavioral and Population Ecology; School of Biological Sciences; Seoul National University; Seoul 151-747 South Korea
| | | | - Hae Jun Baek
- Conservation Genome Research Bank for Korean Wildlife; College of Veterinary Medicine; Seoul National University; Seoul 151-742 South Korea
| | - Hang Lee
- Conservation Genome Research Bank for Korean Wildlife; College of Veterinary Medicine; Seoul National University; Seoul 151-742 South Korea
| | - Mi-Sook Min
- Conservation Genome Research Bank for Korean Wildlife; College of Veterinary Medicine; Seoul National University; Seoul 151-742 South Korea
| | - Bruce Waldman
- Laboratory of Behavioral and Population Ecology; School of Biological Sciences; Seoul National University; Seoul 151-747 South Korea
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