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Becker BM, Banson I, Walker JM, Deshwal A, Brown MW, Silberman JD. Isolation of Naegleria lustrarea n. sp. (Excavata, Discoba, Heterolobosea) from the feces of Ambystoma annulatum (Ringed Salamander) in Northwest Arkansas. J Eukaryot Microbiol 2024; 71:e13031. [PMID: 38725295 DOI: 10.1111/jeu.13031] [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: 02/10/2024] [Revised: 04/10/2024] [Accepted: 04/18/2024] [Indexed: 07/17/2024]
Abstract
The salamander, Ambystoma annulatum, is considered a "species of special concern" in the state of Arkansas, USA, due to its limited geographic range, specialized habitat requirements and low population size. Although metazoan parasites have been documented in this salamander species, neither its native protists nor microbiome have yet been evaluated. This is likely due to the elusive nature and under-sampling of the animal. Here, we initiate the cataloguing of microbial associates with the identification of a new heterlobosean species, Naegleria lustrarea n. sp. (Excavata, Discoba, Heterolobosea), isolated from feces of an adult A. annulatum.
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Affiliation(s)
- Brian M Becker
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA
| | - Idan Banson
- Department of Biological Sciences, Mississippi State University, Mississippi State, Mississippi, USA
| | - James M Walker
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA
| | - Anant Deshwal
- Department of Biology, Bradley University, Peoria, Illinois, USA
| | - Matthew W Brown
- Department of Biological Sciences, Mississippi State University, Mississippi State, Mississippi, USA
| | - Jeffery D Silberman
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA
- Biology Center CAS, Institute of Parasitology, Ceske Budejovice, Czech Republic
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2
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Nenciarini S, Renzi S, di Paola M, Meriggi N, Cavalieri D. The yeast-human coevolution: Fungal transition from passengers, colonizers, and invaders. WIREs Mech Dis 2024; 16:e1639. [PMID: 38146626 DOI: 10.1002/wsbm.1639] [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: 05/19/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 12/27/2023]
Abstract
Fungi are the cause of more than a billion infections in humans every year, although their interactions with the host are still neglected compared to bacteria. Major systemic fungal infections are very unusual in the healthy population, due to the long history of coevolution with the human host. Humans are routinely exposed to environmental fungi and can host a commensal mycobiota, which is increasingly considered as a key player in health and disease. Here, we review the current knowledge on host-fungi coevolution and the factors that regulate their interaction. On one hand, fungi have learned to survive and inhabit the host organisms as a natural ecosystem, on the other hand, the host immune system finely tunes the response toward fungi. In turn, recognition of fungi as commensals or pathogens regulates the host immune balance in health and disease. In the human gut ecosystem, yeasts provide a fingerprint of the transient microbiota. Their status as passengers or colonizers is related to the integrity of the gut barrier and the risk of multiple disorders. Thus, the study of this less known component of the microbiota could unravel the rules of the transition from passengers to colonizers and invaders, as well as their dependence on the innate component of the host's immune response. This article is categorized under: Infectious Diseases > Environmental Factors Immune System Diseases > Environmental Factors Infectious Diseases > Molecular and Cellular Physiology.
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Affiliation(s)
| | - Sonia Renzi
- Department of Biology, University of Florence, Florence, Italy
| | - Monica di Paola
- Department of Biology, University of Florence, Florence, Italy
| | - Niccolò Meriggi
- Department of Biology, University of Florence, Florence, Italy
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3
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Garcia Neto PG, Titon SCM, Muxel SM, Titon B, Figueiredo ACD, Floreste FR, Lima AS, Assis VR, Gomes FR. Immune and endocrine alterations at the early stage of inflammatory assemblage in toads after stimulation with heat-killed bacteria (Aeromonas hydrophila). Comp Biochem Physiol A Mol Integr Physiol 2024; 291:111606. [PMID: 38354902 DOI: 10.1016/j.cbpa.2024.111606] [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: 11/20/2023] [Revised: 02/07/2024] [Accepted: 02/10/2024] [Indexed: 02/16/2024]
Abstract
The red-leg syndrome in amphibians is a condition commonly associated with the bacteria Aeromonas hydrophila and has led to population declines. However, there is little information concerning the inflammatory assemblage in infected anurans. We evaluated immune and endocrine alterations induced by stimulation with heat-killed A. hydrophila injected in Rhinella diptycha toads. Control animals were not manipulated, while the others were separated into groups that received intraperitoneal injection of 300 μl of saline or heat-killed bacteria: groups A1 (3 × 107 cells), A2 (3 × 108 cells), and A3 (3 × 109 cells). Animals were bled and euthanized six hours post-injection. We evaluated neutrophil: lymphocyte ratio (NLR), plasma bacterial killing ability (BKA), testosterone (T), melatonin (MEL), and corticosterone (CORT) plasma levels. Heat-killed A. hydrophila increased CORT and NLR, and decreased MEL, especially at higher concentrations. There was no effect of treatment on T and BKA. We then selected the saline and A3 groups to conduct mRNA expression of several genes including glucocorticoid receptor (GR), toll-like receptor-4 (TLR-4), interferon-γ (IFN-γ), interleukin (IL)-1β, IL-6, and IL-10. We found higher expression of IL-6, IL-1β, IL-10, and IFN-γ in group A3 compared to the saline group. These results indicate the beginning of an inflammatory assemblage, notably at the two highest concentrations of bacteria, and give a better understanding of how anurans respond to an infection within an integrated perspective, evaluating different physiological aspects. Future studies should investigate later phases of the immune response to elucidate more about the inflammation in amphibians challenged with A. hydrophila.
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Affiliation(s)
- Patrício G Garcia Neto
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão - Travessa 14 - n° 101, Cidade Universitária, São Paulo, SP CEP 05508-900, Brazil.
| | - Stefanny C M Titon
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão - Travessa 14 - n° 101, Cidade Universitária, São Paulo, SP CEP 05508-900, Brazil
| | - Sandra M Muxel
- Laboratório de Neuroimunologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Av. Prof. Lineu Prestes n° 1730, Cidade Universitária, São Paulo, SP CEP 05508-000, Brazil.
| | - Braz Titon
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão - Travessa 14 - n° 101, Cidade Universitária, São Paulo, SP CEP 05508-900, Brazil
| | - Aymam C de Figueiredo
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão - Travessa 14 - n° 101, Cidade Universitária, São Paulo, SP CEP 05508-900, Brazil
| | - Felipe R Floreste
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão - Travessa 14 - n° 101, Cidade Universitária, São Paulo, SP CEP 05508-900, Brazil
| | - Alan S Lima
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão - Travessa 14 - n° 101, Cidade Universitária, São Paulo, SP CEP 05508-900, Brazil
| | - Vania R Assis
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão - Travessa 14 - n° 101, Cidade Universitária, São Paulo, SP CEP 05508-900, Brazil; Global Health and Interdisciplinary Disease Research Center and Center for Genomics, College of Public Health, Interdisciplinary Research Building (IDRB), 3720 Spectrum Boulevard. Tampa, FL 33612-9415, United States. https://twitter.com/VaniaRAssis1
| | - Fernando R Gomes
- Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão - Travessa 14 - n° 101, Cidade Universitária, São Paulo, SP CEP 05508-900, Brazil.
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Ash LV, Campião KM, Teixeira CP, Gotelli NJ. Ranavirus and helminth parasite co-infection in invasive American bullfrogs in the Atlantic forest, Brazil. Int J Parasitol Parasites Wildl 2024; 23:100924. [PMID: 38586581 PMCID: PMC10997893 DOI: 10.1016/j.ijppaw.2024.100924] [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: 10/13/2023] [Revised: 03/10/2024] [Accepted: 03/10/2024] [Indexed: 04/09/2024]
Abstract
Emerging infectious diseases threaten amphibian species across the globe. In Brazil, the American bullfrog (Aquarana catesbeiana) is a highly invasive species that can potentially transmit parasites and pathogens to native amphibians. This is the first assessment of co-infection of Ranavirus and helminth macroparasites in invasive populations of bullfrogs in South America. We collected, measured, and euthanized 65 specimens of A. catesbeiana sampled from 9 sites across three states of Brazil in the Atlantic Forest biome. We collected and identified helminth macroparasites and sampled host liver tissue to test for the presence and load of Ranavirus with quantitative PCR. We documented patterns of prevalence, parasite load, and co-infection with generalized linear mixed models, generalized logistic regressions, and randomization tests. Most individual bullfrogs did not exhibit clinical signs of infection, but the overall Ranavirus prevalence was 27% (95% confidence interval, [CI 17-38]). Bullfrogs were infected with helminth macroparasites from 5 taxa. Co-infection of helminth macroparasites and Ranavirus was also common (21% CI [12-31]). Bullfrog size was positively correlated with total macroparasite abundance and richness, and the best-fitting model included a significant interaction between bullfrog size and Ranavirus infection status. We observed a negative correlation between Ranavirus viral load and nematode abundance (slope = -0.22, P = 0.03). Invasive bullfrogs (A. catesbeiana) in Brazil were frequently infected with both Ranavirus and helminth macroparasites, so adult bullfrogs could serve as reservoir hosts for both pathogens and parasites. However, many macroparasites collected were encysted and not developing. Coinfection patterns suggest a potential interaction between Ranavirus and macroparasites because helminth abundance increased with bullfrog size but was lower in Ranavirus infected individuals. Future studies of bullfrogs in the Atlantic Forest should investigate their potential role in pathogen and parasite transmission to native anurans.
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Affiliation(s)
- Lauren V. Ash
- University of Vermont, Department of Biology, 109 Carrigan Drive, Burlington, VT, 05403, USA
| | - Karla Magalhães Campião
- Laboratório de Interações Biológicas, Departamento de Zoologia, Universidade Federal do Paraná, UFPR, Curitiba, Paraná, Brazil
| | - Cauê Pinheiro Teixeira
- Laboratório de Interações Biológicas, Departamento de Zoologia, Universidade Federal do Paraná, UFPR, Curitiba, Paraná, Brazil
| | - Nicholas J. Gotelli
- University of Vermont, Department of Biology, 109 Carrigan Drive, Burlington, VT, 05403, USA
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Bodinof Jachowski CM, Alaasam V, Blumenthal A, Davis AK, Hopkins WA. The habitat quality paradox: loss of riparian forest cover leads to decreased risk of parasitism and improved body condition in an imperiled amphibian. CONSERVATION PHYSIOLOGY 2024; 12:coad101. [PMID: 38293638 PMCID: PMC10823334 DOI: 10.1093/conphys/coad101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 11/17/2023] [Accepted: 11/28/2023] [Indexed: 02/01/2024]
Abstract
Amphibian declines are a global phenomenon but responses of populations to specific threats are often context dependent and mediated by individual physiological condition. Habitat degradation due to reduced riparian forest cover and parasitism are two threats facing the hellbender salamander (Cryptobranchus alleganiensis), but their potential to interact in nature remains largely unexplored. We investigated associations between forest cover, parasitic infection and physiology of hellbenders to test the hypotheses that physiological condition responds to infection and/or habitat degradation. We sampled 17 stream reaches in southwest Virginia, USA, on a year-round basis from 2013 to 2016 and recorded 841 captures of 405 unique hellbenders. At each capture we documented prevalence of two blood-associated parasites (a leech and trypanosome) and quantified up to three physiological condition indices (body condition, hematocrit, white blood cell [WBC] differentials). We used generalized linear mixed models to describe spatiotemporal variation in parasitic infection and each condition index. In general, living in the most heavily forested stream reaches, where hellbender density was highest, was associated with the greatest risk of parasitism, elevated neutrophil-to-lymphocyte (N:L) ratios and eosinophils, slightly lower hematocrit and lower mean body condition in hellbenders. All condition indices fluctuated temporally in a manner consistent with seasonal variation in hellbender metabolic demands and breeding phenology and were associated with land use during at least part of the year. Paradoxically, relatively low levels of forest cover appeared to confer a potential advantage to individuals in the form of release from parasites and improved body condition. Despite improved body condition, individuals from less forested areas failed to exhibit fluctuating body condition in response to spawning, which was typical in hellbenders from more forested habitats. We postulate this lack of fluctuation could be due to reduced conspecific competition or reproductive investment and/or high rates of filial cannibalism in response to declining forest cover.
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Affiliation(s)
- Catherine M Bodinof Jachowski
- Department of Forestry and Environmental Conservation, Clemson University, Clemson, SC 29634, USA
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA
| | | | - Arden Blumenthal
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA
| | - Andrew K Davis
- Odum School of Ecology, University of Georgia, Athens, GA 30602, USA
| | - William A Hopkins
- Department of Fish and Wildlife Conservation, Virginia Tech, Blacksburg, VA 24061, USA
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Apakupakul K, Duncan M, Subramaniam K, Brenn-White M, Palmer JL, Viadanna PHO, Vann JA, Adamovicz L, Waltzek TB, Deem SL. Ranavirus (Frog Virus 3) Infection in Free-Living Three-Toed Box Turtles (Terrapene mexicana triunguis) in Missouri, USA. J Wildl Dis 2024; 60:151-163. [PMID: 37921651 DOI: 10.7589/jwd-d-23-00057] [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: 04/03/2023] [Accepted: 07/28/2023] [Indexed: 11/04/2023]
Abstract
Frog virus 3 (FV3) and related ranaviruses are emerging infectious disease threats to ectothermic vertebrate species globally. Although the impact of these viruses on amphibian health is relatively well studied, less is understood about their effects on reptile health. We report two cases of FV3 infection, 11 mo apart, in three-toed box turtles (Terrapene mexicana triunguis) from a wildlife rehabilitation center. Case 1 had upper respiratory signs upon intake but had no clinical signs at the time of euthanasia 1 mo later. Case 2 presented for vehicular trauma, had ulcerative pharyngitis and glossitis, and died overnight. In case 1, we detected FV3 nucleic acid with qPCR in oral swabs, kidney, liver, spleen, and tongue. In case 2, we detected FV3 in an oral swab, an oral plaque, heart, kidney, lung, liver, spleen, and tongue. We also detected FV3 nucleic acid with in situ hybridization for case 2. For both cases, FV3 was isolated in cell culture and identified with DNA sequencing. Histopathologic examination of postmortem tissue from case 1 was unremarkable, whereas acute hemorrhagic pneumonia and splenic necrosis were noted in case 2. The difference in clinical signs between the two cases may have been due to differences in the temporal course of FV3 disease at the time of necropsy. Failure to detect this infection previously in Missouri reptiles may be due to lack of surveillance, although cases may also represent a novel spillover to box turtles in Missouri. Our findings reiterate previous suggestions that the range of FV3 infection may be greater than previously documented and that infection may occur in host species yet to be tested.
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Affiliation(s)
- Kathleen Apakupakul
- Saint Louis Zoo Institute for Conservation Medicine, 1 Government Dr., St. Louis, Missouri 63110, USA
| | - Mary Duncan
- Saint Louis Zoo Department of Animal Health, 1 Government Dr., St. Louis, Missouri 63110, USA
| | - Kuttichantran Subramaniam
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, 2187 Mowry Rd., Bldg. 0471, Gainesville, Florida 32611, USA
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Rd., Gainesville, Florida 32610, USA
| | - Maris Brenn-White
- Saint Louis Zoo Institute for Conservation Medicine, 1 Government Dr., St. Louis, Missouri 63110, USA
| | - Jamie L Palmer
- Saint Louis Zoo Institute for Conservation Medicine, 1 Government Dr., St. Louis, Missouri 63110, USA
| | - Pedro H O Viadanna
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, 2187 Mowry Rd., Bldg. 0471, Gainesville, Florida 32611, USA
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Rd., Gainesville, Florida 32610, USA
| | - Jordan A Vann
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, 2187 Mowry Rd., Bldg. 0471, Gainesville, Florida 32611, USA
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Rd., Gainesville, Florida 32610, USA
| | - Laura Adamovicz
- Wildlife Epidemiology Laboratory, University of Illinois College of Veterinary Medicine, 2001 S. Lincoln Ave., Urbana, Illinois 61802, USA
| | - Thomas B Waltzek
- Department of Infectious Diseases and Immunology, College of Veterinary Medicine, University of Florida, 2187 Mowry Rd., Bldg. 0471, Gainesville, Florida 32611, USA
- Emerging Pathogens Institute, University of Florida, 2055 Mowry Rd., Gainesville, Florida 32610, USA
- Current affiliation: Washington Animal Disease Diagnostic Laboratory and Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, P.O. Box 647034, Pullman, Washington, USA
| | - Sharon L Deem
- Saint Louis Zoo Institute for Conservation Medicine, 1 Government Dr., St. Louis, Missouri 63110, USA
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Parry RH, Slonchak A, Campbell LJ, Newton ND, Debat HJ, Gifford RJ, Khromykh AA. A novel tamanavirus ( Flaviviridae) of the European common frog ( Rana temporaria) from the UK. J Gen Virol 2023; 104:001927. [PMID: 38059479 PMCID: PMC10770923 DOI: 10.1099/jgv.0.001927] [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: 07/07/2023] [Accepted: 11/19/2023] [Indexed: 12/08/2023] Open
Abstract
Flavivirids are small, enveloped, positive-sense RNA viruses from the family Flaviviridae with genomes of ~9-13 kb. Metatranscriptomic analyses of metazoan organisms have revealed a diversity of flavivirus-like or flavivirid viral sequences in fish and marine invertebrate groups. However, no flavivirus-like virus has been identified in amphibians. To remedy this, we investigated the virome of the European common frog (Rana temporaria) in the UK, utilizing high-throughput sequencing at six catch locations. De novo assembly revealed a coding-complete virus contig of a novel flavivirid ~11.2 kb in length. The virus encodes a single ORF of 3456 aa and 5' and 3' untranslated regions (UTRs) of 227 and 666 nt, respectively. We named this virus Rana tamanavirus (RaTV), as BLASTp analysis of the polyprotein showed the closest relationships to Tamana bat virus (TABV) and Cyclopterus lumpus virus from Pteronotus parnellii and Cyclopterus lumpus, respectively. Phylogenetic analysis of the RaTV polyprotein compared to Flavivirus and Flavivirus-like members indicated that RaTV was sufficiently divergent and basal to the vertebrate Tamanavirus clade. In addition to the Mitcham strain, partial but divergent RaTV, sharing 95.64-97.39 % pairwise nucleotide identity, were also obtained from the Poole and Deal samples, indicating that RaTV is widespread in UK frog samples. Bioinformatic analyses of predicted secondary structures in the 3'UTR of RaTV showed the presence of an exoribonuclease-resistant RNA (xrRNA) structure standard in flaviviruses and TABV. To examine this biochemically, we conducted an in vitro Xrn1 digestion assay showing that RaTV probably forms a functional Xrn1-resistant xrRNA.
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Affiliation(s)
- Rhys H. Parry
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
| | - Andrii Slonchak
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
- Australian Infectious Diseases Research Centre (AIDRC), Brisbane, QLD, Australia
| | - Lewis J. Campbell
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI, USA
- Institute of Zoology, Zoological Society of London, London, UK
- Environment and Sustainability Institute, University of Exeter, Penryn, UK
| | - Natalee D. Newton
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
- Australian Infectious Diseases Research Centre (AIDRC), Brisbane, QLD, Australia
| | - Humberto J. Debat
- Instituto de Patología Vegetal, Centro de Investigaciones Agropecuarias, Instituto Nacional de Tecnología Agropecuaria (IPAVE-CIAP-INTA), Córdoba X5020ICA, Argentina
- Unidad de Fitopatología y Modelización Agrícola (UFYMA), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Córdoba X5020ICA, Argentina
| | | | - Alexander A. Khromykh
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, Australia
- Australian Infectious Diseases Research Centre (AIDRC), Brisbane, QLD, Australia
- AIDRC Global Virus Network Centre of Excellence, Brisbane, QLD, Australia
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Holt WV. Biobanks, offspring fitness and the influence of developmental plasticity in conservation biology. Anim Reprod 2023; 20:e20230026. [PMID: 37700907 PMCID: PMC10494884 DOI: 10.1590/1984-3143-ar2023-0026] [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: 02/19/2023] [Accepted: 07/05/2023] [Indexed: 09/14/2023] Open
Abstract
Mitigation of the widely known threats to the world's biodiversity is difficult, despite the strategies and actions proposed by international agreements such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Convention on Biological Diversity (CBD). Nevertheless, many scientists devote their time and effort to finding and implementing various solutions to the problem. One potential way forward that is gaining popularity involves the establishment of biobank programs aimed at preserving and storing germplasm from threatened species, and then using it to support the future viability and health of threatened populations. This involves developing and using assisted reproductive technologies to achieve their goals. Despite considerable advances in the effectiveness of reproductive technologies, differences between the reproductive behavior and physiology of widely differing taxonomic groups mean that this approach cannot be applied with equal success to many species. Moreover, evidence that epigenetic influences and developmental plasticity, whereby it is now understood that embryonic development, and subsequent health in later life, can be affected by peri-conceptional environmental conditions, is raising the possibility that cryopreservation methods themselves may have to be reviewed and revised when planning the biobanks. Here, I describe the benefits and problems associated with germplasm biobanking across various species, but also offer some realistic assessments of current progress and applications.
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Affiliation(s)
- William Vincent Holt
- Academic Unit of Reproductive and Developmental Medicine, University of Sheffield, Sheffield, United Kingdom
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Miller AJ, Gass J, Jo MC, Bishop L, Petereit J, Woodhams DC, Voyles J. Towards the generation of gnotobiotic larvae as a tool to investigate the influence of the microbiome on the development of the amphibian immune system. Philos Trans R Soc Lond B Biol Sci 2023; 378:20220125. [PMID: 37305911 PMCID: PMC10258664 DOI: 10.1098/rstb.2022.0125] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/28/2022] [Indexed: 06/13/2023] Open
Abstract
The immune equilibrium model suggests that exposure to microbes during early life primes immune responses for pathogen exposure later in life. While recent studies using a range of gnotobiotic (germ-free) model organisms offer support for this theory, we currently lack a tractable model system for investigating the influence of the microbiome on immune system development. Here, we used an amphibian species (Xenopus laevis) to investigate the importance of the microbiome in larval development and susceptibility to infectious disease later in life. We found that experimental reductions of the microbiome during embryonic and larval stages effectively reduced microbial richness, diversity and altered community composition in tadpoles prior to metamorphosis. In addition, our antimicrobial treatments resulted in few negative effects on larval development, body condition, or survival to metamorphosis. However, contrary to our predictions, our antimicrobial treatments did not alter susceptibility to the lethal fungal pathogen Batrachochytrium dendrobatidis (Bd) in the adult life stage. While our treatments to reduce the microbiome during early development did not play a critical role in determining susceptibility to disease caused by Bd in X. laevis, they nevertheless indicate that developing a gnotobiotic amphibian model system may be highly useful for future immunological investigations. This article is part of the theme issue 'Amphibian immunity: stress, disease and ecoimmunology'.
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Affiliation(s)
| | - Jordan Gass
- Department of Biology, University of Nevada, Reno, NV 89557, USA
| | - Myung Chul Jo
- Environmental Health and Safety, University of Nevada, Reno, NV 89557, USA
| | - Lucas Bishop
- Nevada Bioinformatics Center, University of Nevada, Reno, NV 89557, USA
| | - Juli Petereit
- Nevada Bioinformatics Center, University of Nevada, Reno, NV 89557, USA
| | | | - Jamie Voyles
- Department of Biology, University of Nevada, Reno, NV 89557, USA
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Douglas AJ, Todd LA, Katzenback BA. The amphibian invitrome: Past, present, and future contributions to our understanding of amphibian immunity. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2023; 142:104644. [PMID: 36708792 DOI: 10.1016/j.dci.2023.104644] [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: 11/20/2022] [Revised: 01/18/2023] [Accepted: 01/18/2023] [Indexed: 06/18/2023]
Abstract
Many amphibian populations are declining worldwide, and infectious diseases are a leading cause. Given the eminent threat infectious diseases pose to amphibian populations, there is a need to understand the host-pathogen-environment interactions that govern amphibian susceptibility to disease and mortality events. However, using animals in research raises an ethical dilemma, which is magnified by the alarming rates at which many amphibian populations are declining. Thus, in vitro study systems such as cell lines represent valuable tools for furthering our understanding of amphibian immune systems. In this review, we curate a list of the amphibian cell lines established to date (the amphibian invitrome), highlight how research using amphibian cell lines has advanced our understanding of the amphibian immune system, anti-ranaviral defence mechanisms, and Batrachochytrium dendrobatidis replication in host cells, and offer our perspective on how future use of amphibian cell lines can advance the field of amphibian immunology.
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Affiliation(s)
- Alexander J Douglas
- Department of Biology, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
| | - Lauren A Todd
- Department of Biology, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada
| | - Barbara A Katzenback
- Department of Biology, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
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11
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Zhao Z, Huang Y, Liu C, Zhu D, Gao S, Liu S, Peng R, Zhang Y, Huang X, Qi J, Wong CCL, Zhang X, Wang P, Qin Q, Gao GF. Near-atomic architecture of Singapore grouper iridovirus and implications for giant virus assembly. Nat Commun 2023; 14:2050. [PMID: 37041173 PMCID: PMC10090177 DOI: 10.1038/s41467-023-37681-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 03/28/2023] [Indexed: 04/13/2023] Open
Abstract
Singapore grouper iridovirus (SGIV), one of the nucleocytoviricota viruses (NCVs), is a highly pathogenic iridovirid. SGIV infection results in massive economic losses to the aquaculture industry and significantly threatens global biodiversity. In recent years, high morbidity and mortality in aquatic animals have been caused by iridovirid infections worldwide. Effective control and prevention strategies are urgently needed. Here, we present a near-atomic architecture of the SGIV capsid and identify eight types of capsid proteins. The viral inner membrane-integrated anchor protein colocalizes with the endoplasmic reticulum (ER), supporting the hypothesis that the biogenesis of the inner membrane is associated with the ER. Additionally, immunofluorescence assays indicate minor capsid proteins (mCPs) could form various building blocks with major capsid proteins (MCPs) before the formation of a viral factory (VF). These results expand our understanding of the capsid assembly of NCVs and provide more targets for vaccine and drug design to fight iridovirid infections.
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Affiliation(s)
- Zhennan Zhao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Youhua Huang
- College of Marine Sciences, South China Agricultural University, Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Congcong Liu
- Cryo-EM Center, Department of Biology, Southern University of Science and Technology, Shenzhen, 518055, China
- Institute for Hepatology, National Clinical Research Center for Infectious Disease, Shenzhen Third People's Hospital, Shenzhen, 518112, China
| | - Dongjie Zhu
- School of Life Science, University of Science and Technology of China, Hefei, 230026, China
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Shuaixin Gao
- Clinical Research Institute, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing, 100730, China
- Department of Human Sciences & James Comprehensive Cancer Center, The Ohio State University, Columbus, 43210, USA
| | - Sheng Liu
- Cryo-EM Center, Department of Biology, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Ruchao Peng
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- Perelman School of Medicine, University of Pennsylvania, Philadelphia, 19104, USA
| | - Ya Zhang
- College of Marine Sciences, South China Agricultural University, Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Xiaohong Huang
- College of Marine Sciences, South China Agricultural University, Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China
| | - Jianxun Qi
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
- Beijing Life Science Academy, Beijing, 102209, China.
| | - Catherine C L Wong
- Clinical Research Institute, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science & Peking Union Medical College, Beijing, 100730, China.
| | - Xinzheng Zhang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Peiyi Wang
- Cryo-EM Center, Department of Biology, Southern University of Science and Technology, Shenzhen, 518055, China.
| | - Qiwei Qin
- College of Marine Sciences, South China Agricultural University, Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, 510642, China.
| | - George F Gao
- CAS Key Laboratory of Pathogen Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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12
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Payne N, Combrink L, Kraberger S, Fontenele RS, Schmidlin K, Cassaigne I, Culver M, Varsani A, Van Doorslaer K. DNA virome composition of two sympatric wild felids, bobcat (Lynx rufus) and puma (Puma concolor) in Sonora, Mexico. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1126149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023] Open
Abstract
With viruses often having devastating effects on wildlife population fitness and wild mammals serving as pathogen reservoirs for potentially zoonotic diseases, determining the viral diversity present in wild mammals is both a conservation and One Health priority. Additionally, transmission from more abundant hosts could increase the extinction risk of threatened sympatric species. We leveraged an existing circular DNA enriched metagenomic dataset generated from bobcat (Lynx rufus, n = 9) and puma (Puma concolor, n = 13) scat samples non-invasively collected from Sonora, Mexico, to characterize fecal DNA viromes of each species and determine the extent that viruses are shared between them. Using the metaWRAP pipeline to co-assemble viral genomes for comparative metagenomic analysis, we observed diverse circular DNA viruses in both species, including circoviruses, genomoviruses, and anelloviruses. We found that differences in DNA virome composition were partly attributed to host species, although there was overlap between viruses in bobcats and pumas. Pumas exhibited greater levels of alpha diversity, possibly due to bioaccumulation of pathogens in apex predators. Shared viral taxa may reflect dietary overlap, shared environmental resources, or transmission through host interactions, although we cannot rule out species-specific host-virus coevolution for the taxa detected through co-assembly. However, our detection of integrated feline foamy virus (FFV) suggests Sonoran pumas may interact with domestic cats. Our results contribute to the growing baseline knowledge of wild felid viral diversity. Future research including samples from additional sources (e.g., prey items, tissues) may help to clarify host associations and determine the pathogenicity of detected viruses.
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Flechas SV, Urbina J, Crawford AJ, Gutiérrez K, Corrales K, Castellanos LA, González MA, Cuervo AM, Catenazzi A. First evidence of ranavirus in native and invasive amphibians in Colombia. DISEASES OF AQUATIC ORGANISMS 2023; 153:51-58. [PMID: 36794841 DOI: 10.3354/dao03717] [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: 06/18/2023]
Abstract
Ranaviruses can cause mass mortality events in amphibians, thereby becoming a threat to populations that are already facing dramatic declines. Ranaviruses affect all life stages and persist in multiple amphibian hosts. The detrimental effects of ranavirus infections to amphibian populations have already been observed in the UK and in North America. In Central and South America, the virus has been reported in several countries, but the presence of the genus Ranavirus (Rv) in Colombia is unknown. To help fill this knowledge gap, we surveyed for Rv in 60 species of frogs (including one invasive species) in Colombia. We also tested for co-infection with Batrachochytrium dendrobatidis (Bd) in a subset of individuals. For Rv, we sampled 274 vouchered liver tissue samples collected between 2014 and 2019 from 41 localities covering lowlands to mountaintop páramo habitat across the country. Using quantitative polymerase chain reaction (qPCR) and end-point PCR, we detected Rv in 14 individuals from 8 localities, representing 6 species, including 5 native frogs of the genera Osornophryne, Pristimantis and Leptodactylus, and the invasive American bullfrog Rana catesbeiana. Bd was detected in 7 of 140 individuals, with 1 co-infection of Rv and Bd in an R. catesbeiana specimen collected in 2018. This constitutes the first report of ranavirus in Colombia and should set off alarms about this new emerging threat to amphibian populations in the country. Our findings provide some preliminary clues about how and when Rv may have spread and contribute to understanding how the pathogen is distributed globally.
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Affiliation(s)
- Sandra V Flechas
- Instituto de Investigación de Recursos Biológicos Alexander von Humboldt, Bogotá, 110321, Colombia
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14
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Auliya M, Altherr S, Nithart C, Hughes A, Bickford D. Numerous uncertainties in the multifaceted global trade in frogs’ legs with the EU as the major consumer. NATURE CONSERVATION 2023. [DOI: 10.3897/natureconservation.51.93868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The commercial trade in frogs and their body parts is global, dynamic and occurs in extremely large volumes (in the thousands of tonnes/yr or billions of frogs/yr). The European Union (EU) remains the single largest importer of frogs’ legs, with most frogs still caught from the wild. Amongst the many drivers of species extinction or population decline (e.g. due to habitat loss, climate change, disease etc.), overexploitation is becoming increasingly more prominent. Due to global declines and extinctions, new attention is being focused on these markets, in part to try to ensure sustainability. While the trade is plagued by daunting realities of data deficiency and uncertainty and the conflicts of commercial interests associated with these data, it is clear is that EU countries are most responsible for the largest portion of the international trade in frogs’ legs of wild species. Over decades of exploitation, the EU imports have contributed to a decline in wild frog populations in an increasing number of supplying countries, such as India and Bangladesh, as well as Indonesia, Turkey and Albania more recently. However, there have been no concerted attempts by the EU and present export countries to ensure sustainability of this trade. Further work is needed to validate species identities, secure data on wild frog populations, establish reasonable monitored harvest/export quotas and disease surveillance and ensure data integrity, quality and security standards for frog farms. Herein, we call upon those countries and their representative governments to assume responsibility for the sustainability of the trade. The EU should take immediate action to channel all imports through a single centralised database and list sensitive species in the Annexes of the EU Wildlife Trade Regulation. Further, listing in CITES (the Convention on International Trade in Endangered Species of Wild Fauna and Flora) can enforce international trade restrictions. More joint efforts are needed to improve regional monitoring schemes before the commercial trade causes irreversible extinctions of populations and species of frogs.
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15
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Bilhalva LC, de Almeida BA, Colombo P, de Faria Valle S, Soares JF. Hematologic variables of free-living Leptodactylus luctator with and without hemoparasites and thrombidiform mites in southern Brazil. Vet Parasitol Reg Stud Reports 2023; 38:100834. [PMID: 36725158 DOI: 10.1016/j.vprsr.2023.100834] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 12/15/2022] [Accepted: 01/06/2023] [Indexed: 01/09/2023]
Abstract
It has been suggested that anuran amphibian parasites can cause clinical signs in situations of environmental imbalance. In the family Leptodactylidae, information about hematology is scarce, although these are well-known tools for the diagnosis and prognosis in clinical practice and potential bioindicators of environmental stress. The objective of this study is to describe Leptodactylus luctator hematology, to report the occurrence of hemoparasites and thrombidiform mites, and to compare the hematological variables under the presence and absence of these organisms. Ectoparasites and heparinized blood samples from 40 free-living specimens of L. luctator were collected for analysis. Hematologic variables and total plasma protein were compared between groups with and without hemoparasites and intradermal mites. As results, structures compatible with hemogregarines, Lankesterella sp., five morphotypes of Trypanosoma spp., microfilaria, Aegyptianella sp., an unidentified intraleukocytic hemoparasite, and frog erythrocytic virus (FEV) inclusion bodies were identified in the blood samples, besides Hannemania spp. intradermal mites. The hemoparasite occurrence was higher than previously reported in other anuran families and locations. Also, L. luctator has smaller red blood cells (RBCs) and white blood cells (WBCs), and a hyposegmentation of the neutrophil nucleus, when compared to many other amphibians. White blood cell, neutrophil, and monocyte counts were higher in animals parasitized by mites. There was no correlation between the number of parasitized RBCs and hematologic variables. This study provides anuran hematologic information, in addition to indicating a host reaction to infestation by Hannemania spp. mites, besides constituting the first record of the distribution of hemoparasites and intradermal mites in L. luctator of the study region.
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Affiliation(s)
- Lina Crespo Bilhalva
- Department of Veterinary Clinical Pathology, Veterinary Medicine College, Federal University of Rio Grande do Sul (UFRGS), 9090 Bento Gonçalves Ave., Porto Alegre 91540-000, Rio Grande do Sul, Brazil
| | - Bruno Albuquerque de Almeida
- Department of Veterinary Clinical Pathology, Veterinary Medicine College, Federal University of Rio Grande do Sul (UFRGS), 9090 Bento Gonçalves Ave., Porto Alegre 91540-000, Rio Grande do Sul, Brazil
| | - Patrick Colombo
- Zoobotanical Foundation of Rio Grande do Sul (FZB-RS), 1427 Dr. Salvador França Ave., Porto Alegre 90690-000, Rio Grande do Sul, Brazil
| | - Stella de Faria Valle
- Department of Veterinary Clinical Pathology, Veterinary Medicine College, Federal University of Rio Grande do Sul (UFRGS), 9090 Bento Gonçalves Ave., Porto Alegre 91540-000, Rio Grande do Sul, Brazil.
| | - João Fabio Soares
- Department of Veterinary Clinical Pathology, Veterinary Medicine College, Federal University of Rio Grande do Sul (UFRGS), 9090 Bento Gonçalves Ave., Porto Alegre 91540-000, Rio Grande do Sul, Brazil
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16
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Lin X, Liu H, Han X, Wei Y. Stability and Hopf bifurcation of an SIR epidemic model with density-dependent transmission and Allee effect. MATHEMATICAL BIOSCIENCES AND ENGINEERING : MBE 2023; 20:2750-2775. [PMID: 36899556 DOI: 10.3934/mbe.2023129] [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: 06/18/2023]
Abstract
In this paper, an SIR model with a strong Allee effect and density-dependent transmission is proposed, and its characteristic dynamics are investigated. The elementary mathematical characteristic of the model is studied, including positivity, boundedness and the existence of equilibrium. The local asymptotic stability of the equilibrium points is analyzed using linear stability analysis. Our results indicate that the asymptotic dynamics of the model are not only determined using the basic reproduction number ${R_0}$. If ${R_0} < 1$, there are three disease-free equilibrium points, and a disease-free equilibrium is always stable. At the same time, the conditions for other disease-free equilibrium points to be bistable were determined. If ${R_0} > 1$ and in certain conditions, either an endemic equilibrium emerges and is locally asymptotically stable, or the endemic equilibrium becomes unstable. What must be emphasized is that there is a locally asymptotically stable limit cycle when the latter happens. The Hopf bifurcation of the model is also discussed using topological normal forms. The stable limit cycle can be interpreted in a biological significance as a recurrence of the disease. Numerical simulations are used to verify the theoretical analysis. Taking into account both density-dependent transmission of infectious diseases and the Allee effect, the dynamic behavior becomes more interesting than when considering only one of them in the model. The Allee effect makes the SIR epidemic model bistable, which also makes the disappearance of diseases possible, since the disease-free equilibrium in the model is locally asymptotically stable. At the same time, persistent oscillations due to the synergistic effect of density-dependent transmission and the Allee effect may explain the recurrence and disappearance of disease.
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Affiliation(s)
- Xiaofen Lin
- School of Mathematics and Computer Science, Northwest Minzu University, Lanzhou 730030, China
| | - Hua Liu
- School of Mathematics and Computer Science, Northwest Minzu University, Lanzhou 730030, China
| | - Xiaotao Han
- School of Mathematics and Computer Science, Northwest Minzu University, Lanzhou 730030, China
| | - Yumei Wei
- Experimental Teaching Deparment, Northwest Minzu University, Lanzhou 730030, China
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17
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Strachinis I, Marschang RE, Lymberakis P, Karagianni KM, Azmanis P. Infectious disease threats to amphibians in Greece: new localities positive for Batrachochytrium dendrobatidis. DISEASES OF AQUATIC ORGANISMS 2022; 152:127-138. [PMID: 36519684 DOI: 10.3354/dao03712] [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: 06/17/2023]
Abstract
In the early 2000s, numerous cases of European amphibian population declines and mass die-offs started to emerge. Investigating those events led to the discovery that wild European amphibians were confronted with grave disease threats caused by introduced pathogens, namely the amphibian and the salamander chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal) and ranaviruses. In Greece, Bd was previously documented among wild amphibian populations in 2 different locations and 3 different species. However, no disease-related mass declines or mortality events have been reported. In this work, we build upon previous findings with new, subsequently obtained data, resulting in a 225-sample dataset of 14 species from 17 different locations throughout Greece, in order to examine the occurrence status of all 3 pathogens responsible for emerging infectious diseases in European amphibians. No positive samples for Bsal or ranavirus were recorded in any location. We confirmed the presence of Bd in 4 more localities and in 4 more species, including 1 urodelan (Macedonian crested newt Triturus macedonicus) and 1 introduced anuran (American bullfrog Lithobates catesbeianus). All insular localities were negative for Bd, except for Crete, where Bd was identified in 2 different locations. Again, no mass declines or die-offs were recorded in any Bd-positive area or elsewhere. However, given the persistence of Bd across Greece over the past ~20 yr, monitoring efforts should continue, and ideally be further expanded.
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Affiliation(s)
- Ilias Strachinis
- Department of Genetics, Development and Molecular Biology, School of Biology, Faculty of Natural Sciences, Aristotle University of Thessaloniki, 54636, Greece
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18
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Population genetic structure and evolutionary demographic patterns of Phrynoderma karaavali, an edible frog species of Kerala, India. J Genet 2022. [DOI: 10.1007/s12041-022-01407-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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19
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Adams AJ, Bushell J, Grasso RL. To treat or not to treat? Experimental pathogen exposure, treatment, and release of a threatened amphibian. Ecosphere 2022. [DOI: 10.1002/ecs2.4294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Affiliation(s)
- Andrea J. Adams
- Resources Management and Science Division Yosemite National Park El Portal California USA
- Earth Research Institute University of California Santa Barbara California USA
| | | | - Robert L. Grasso
- Resources Management and Science Division Yosemite National Park El Portal California USA
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20
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Cevallos MA, Basanta MD, Bello-López E, Escobedo-Muñoz AS, González-Serrano FM, Nemec A, Romero-Contreras YJ, Serrano M, Rebollar EA. Genomic characterization of antifungal Acinetobacter bacteria isolated from the skin of the frogs Agalychnis callidryas and Craugastor fitzingeri. FEMS Microbiol Ecol 2022; 98:6775075. [PMID: 36288213 DOI: 10.1093/femsec/fiac126] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 10/09/2022] [Accepted: 10/24/2022] [Indexed: 01/21/2023] Open
Abstract
Chytridiomycosis, a lethal fungal disease caused by Batrachochytrium dendrobatidis (Bd), is responsible for population declines and extinctions of amphibians worldwide. However, not all amphibian species are equally susceptible to the disease; some species persist in Bd enzootic regions with no population reductions. Recently, it has been shown that the amphibian skin microbiome plays a crucial role in the defense against Bd. Numerous bacterial isolates with the capacity to inhibit the growth of Batrachochytrium fungi have been isolated from the skin of amphibians. Here, we characterized eight Acinetobacter bacteria isolated from the frogs Agalychnis callidryas and Craugastor fitzingeri at the genomic level. A total of five isolates belonged to Acinetobacter pittii,Acinetobacter radioresistens, or Acinetobactermodestus, and three were not identified as any of the known species, suggesting they are members of new species. We showed that seven isolates inhibited the growth of Bd and that all eight isolates inhibited the growth of the phytopathogen fungus Botrytis cinerea. Finally, we identified the biosynthetic gene clusters that could be involved in the antifungal activity of these isolates. Our results suggest that the frog skin microbiome includes Acinetobacter isolates that are new to science and have broad antifungal functions, perhaps driven by distinct genetic mechanisms.
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Affiliation(s)
- M A Cevallos
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Cuernavaca, Morelos, 62220, México
| | - M D Basanta
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Cuernavaca, Morelos, 62220, México.,Department of Biology, University of Nevada Reno, 1664 N Virgina St, Reno, NV 89557, United States
| | - E Bello-López
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Cuernavaca, Morelos, 62220, México
| | - A S Escobedo-Muñoz
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Cuernavaca, Morelos, 62220, México
| | - F M González-Serrano
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Cuernavaca, Morelos, 62220, México
| | - A Nemec
- Laboratory of Bacterial Genetics, Centre for Epidemiology and Microbiology, National Institute of Public Health, Šrobárova 48, 100 00 Prague 10, Czechia.,Department of Medical Microbiology, Second Faculty of Medicine, Charles University, and Motol University Hospital, V Úvalu 84, 150 06 Prague 5, Czechia
| | - Y J Romero-Contreras
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Cuernavaca, Morelos, 62220, México
| | - M Serrano
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Cuernavaca, Morelos, 62220, México
| | - E A Rebollar
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Avenida Universidad s/n, Cuernavaca, Morelos, 62220, México
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Factors Affecting Post-Challenge Survival of Flavobacterium psychrophilum in Susceptible Rainbow Trout from the Literature. Pathogens 2022; 11:pathogens11111318. [DOI: 10.3390/pathogens11111318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/09/2022] [Accepted: 11/03/2022] [Indexed: 11/12/2022] Open
Abstract
Infectious bacterial pathogens are a concern for aquaculture as estimates suggest that billions of US dollars are lost annually in aquaculture due to disease. One of the most prevalent salmonid pathogens is the bacterium Flavobacterium psychrophilum that causes bacterial coldwater disease. We reviewed the published F. psychrophilum literature and conducted a Bayesian analysis to examine large-scale patterns in rainbow trout (Oncorhynchus mykiss) mortality associated with laboratory challenge. We incorporated factors that were common across a majority of the laboratory exposure studies and these included bacterial dose, culture time, exposure method, bacterial isolate, experimental duration, and fish weight. The comparison showed that injection as the exposure method produced higher mortality than bath immersion, bacterial isolates differed in their effect on mortality, and bacterial dose has an interactive effect with fish weight and exposure method. Our comparison allows for inference on factors affecting rainbow trout mortality due to exposure to F. psychrophilum and suggests avenues to further optimize research protocols to better reach study goals.
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22
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Zamora-Camacho FJ, Zambrano-Fernández S, Aragón P. Long-term sex-dependent inflammatory response of adult frogs to ammonium exposure during the larval stage. CHEMOSPHERE 2022; 307:136202. [PMID: 36037957 DOI: 10.1016/j.chemosphere.2022.136202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/08/2022] [Accepted: 08/22/2022] [Indexed: 06/15/2023]
Abstract
Among others, the global change involves a worldwide increase in cropland area, with the concomitant rise in nitrogenous fertilizer supplementation and species range alterations, including parasites and pathogens. As most animals rely on their immune systems against these infectious agents, studying the potential effects of nitrogenous compounds on animal immune response is vital to understand their susceptibility to infections under these altered circumstances. Being subjected to an alarming process of global declines, amphibians are the object of particular attention, given their sensitivity to these compounds, especially to ammonium. Moreover, whereas adults can actively avoid polluted patches, larvae are confined within their waterbodies, thus exposed to contaminants in it. In this work, we test whether chronic exposure to a sublethal dose of ammonium during the larval stage of Pelophylax perezi frogs, released from all contamination after metamorphosis, leads to impaired inflammatory response to phytohemagglutinin in adults. We also test whether such a response differs between agrosystem individuals as compared with conspecifics from natural habitats. We found negative carryover effects of chronic exposure of larvae to ammonium on adult inflammatory response, which could imply a greater susceptibility to pathogens and parasites. However, this damage is only true for males, which, according to the immunocompetence handicap hypothesis, could be a consequence of a testosterone-triggered impairment of male immune function. In disagreement with our prediction, however, we detected no differences in the inflammatory response of agrosystem frogs to phytohemagglutinin as compared with natural habitat conspecifics.
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Affiliation(s)
- Francisco Javier Zamora-Camacho
- Museo Nacional de Ciencias Naturales, (MNCN-CSIC), C/ José Gutiérrez Abascal 2, 28006, Madrid, Spain; Universidad Complutense de Madrid, C/José Antonio Novais 2, 2804, Madrid, Spain.
| | | | - Pedro Aragón
- Museo Nacional de Ciencias Naturales, (MNCN-CSIC), C/ José Gutiérrez Abascal 2, 28006, Madrid, Spain; Universidad Complutense de Madrid, C/José Antonio Novais 2, 2804, Madrid, Spain
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23
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Singapore Grouper Iridovirus VP131 Drives Degradation of STING-TBK1 Pathway Proteins and Negatively Regulates Antiviral Innate Immunity. J Virol 2022; 96:e0068222. [PMID: 36190239 PMCID: PMC9599571 DOI: 10.1128/jvi.00682-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Iridoviruses are large DNA viruses which cause great economic losses to the aquaculture industry and serious threats to ecological diversity worldwide. Singapore grouper iridovirus (SGIV), a novel member of the genus Ranavirus, causes high mortality in grouper aquaculture. Previous work on genome annotation demonstrated that SGIV contained numerous uncharacterized or hypothetical open reading frames (ORFs), whose functions remained largely unknown. Here, we reported that the protein encoded by SGIV ORF131R (VP131) was localized predominantly within the endoplasmic reticulum (ER). Ectopic expression of GFP-VP131 significantly enhanced SGIV replication, while VP131 knockdown decreased viral infection in vitro, suggesting that VP131 functioned as a proviral factor during SGIV infection. Overexpression of GFP-VP131 inhibited the interferon (IFN)-1 promoter activity and mRNA level of IFN-related genes induced by poly(I:C), Epinephelus coioides cyclic GMP/AMP synthase (EccGAS)/stimulator of IFN genes (EcSTING), TANK-binding kinase 1 (EcTBK1), or melanoma differentiation-associated gene 5 (EcMDA5), whereas such activation induced by mitochondrial antiviral signaling protein (EcMAVS) was not affected. Moreover, VP131 interacted with EcSTING and degraded EcSTING through both the autophagy-lysosome pathway and ubiquitin-proteasome pathway, and targeted for the K63-linked ubiquitination. Of note, we also found that EcSTING significantly accelerated the formation of GFP-VP131 aggregates in co-transfected cells. Finally, GFP-VP131 inhibited EcSTING- or EcTBK1-induced antiviral activity upon red-spotted grouper nervous necrosis virus (RGNNV) infection. Together, our results demonstrated that the SGIV VP131 negatively regulated the IFN response by inhibiting EcSTING-EcTBK1 signaling for viral evasion. IMPORTANCE STING has been identified as a critical factor participating in the innate immune response which recruits and phosphorylates TBK1 and IFN regulatory factor 3 (IRF3) to induce IFN production and defend against viral infection. However, viruses also distort the STING-TBK1 pathway to negatively regulate the IFN response and facilitate viral replication. Here, we reported that SGIV VP131 interacted with EcSTING within the ER and degraded EcSTING, leading to the suppression of IFN production and the promotion of SGIV infection. These results for the first time demonstrated that fish iridovirus evaded the host antiviral response via abrogating the STING-TBK1 signaling pathway.
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Abd El-Hack ME, El-Saadony MT, Ellakany HF, Elbestawy AR, Abaza SS, Geneedy AM, Khafaga AF, Salem HM, Abd El-Aziz AH, Selim S, Babalghith AO, AbuQamar SF, El-Tarabily KA. Inhibition of microbial pathogens in farmed fish. MARINE POLLUTION BULLETIN 2022; 183:114003. [PMID: 36030638 DOI: 10.1016/j.marpolbul.2022.114003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/18/2022] [Accepted: 07/27/2022] [Indexed: 06/15/2023]
Abstract
Aquaculture, also known as aqua farming, is defined as farming fish, crustaceans, mollusks, aquatic plants, algae, and other marine organisms. It includes cultivating fresh- and saltwater populations under controlled conditions compared to commercial fishing or wild fish harvesting. Worldwide, carp, salmon, tilapia, and catfish are the most common fish species used in fish farming in descending order. Disinfectants prevent and/or treat different infections in aquatic animals. The current review indicates the uses of different disinfectants against some important pathogens in aquaculture, with particular reference to tilapia (Oreochromis niloticus) farming. A single review cannot cover all aspects of disinfection throughout aquaculture, so the procedures and principles of disinfection in tilapia farming/aquaculture have been chosen for illustration purposes.
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Affiliation(s)
- Mohamed E Abd El-Hack
- Department of Poultry, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
| | - Mohamed T El-Saadony
- Department of Agricultural Microbiology, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt
| | - Hany F Ellakany
- Department of Poultry and Fish Diseases, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt
| | - Ahmed R Elbestawy
- Department of Poultry and Fish Diseases, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt
| | - Samar S Abaza
- Department of Poultry and Fish Diseases, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt
| | - Amr M Geneedy
- Department of Poultry and Fish Diseases, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt
| | - Asmaa F Khafaga
- Department of Pathology, Faculty of Veterinary Medicine, Alexandria University, Edfina 22758, Egypt
| | - Heba M Salem
- Department of Poultry Diseases, Faculty of Veterinary Medicine, Cairo University, Giza 12211, Egypt
| | - Ayman H Abd El-Aziz
- Animal Husbandry and Animal Wealth Development Department, Faculty of Veterinary Medicine, Damanhour University, Damanhour 22511, Egypt
| | - Samy Selim
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Jouf University, Sakaka 72388, Saudi Arabia
| | - Ahmad O Babalghith
- Medical Genetics Department, College of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Synan F AbuQamar
- Department of Biology, College of Science, United Arab Emirates University, Al Ain 15551, United Arab Emirates.
| | - Khaled A El-Tarabily
- Department of Biology, College of Science, United Arab Emirates University, Al Ain 15551, United Arab Emirates; Khalifa Center for Genetic Engineering and Biotechnology, United Arab Emirates University, Al Ain 15551, United Arab Emirates; Harry Butler Institute, Murdoch University, Murdoch 6150, Western Australia, Australia.
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Schmeller DS, Cheng T, Shelton J, Lin CF, Chan-Alvarado A, Bernardo-Cravo A, Zoccarato L, Ding TS, Lin YP, Swei A, Fisher MC, Vredenburg VT, Loyau A. Environment is associated with chytrid infection and skin microbiome richness on an amphibian rich island (Taiwan). Sci Rep 2022; 12:16456. [PMID: 36180528 PMCID: PMC9525630 DOI: 10.1038/s41598-022-20547-3] [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: 12/20/2021] [Accepted: 09/14/2022] [Indexed: 11/09/2022] Open
Abstract
Growing evidence suggests that the origins of the panzootic amphibian pathogens Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal) are in Asia. In Taiwan, an island hotspot of high amphibian diversity, no amphibian mass mortality events linked to Bd or Bsal have been reported. We conducted a multi-year study across this subtropical island, sampling 2517 individuals from 30 species at 34 field sites, between 2010 and 2017, and including 171 museum samples collected between 1981 and 2009. We analyzed the skin microbiome of 153 samples (6 species) from 2017 in order to assess any association between the amphibian skin microbiome and the probability of infection amongst different host species. We did not detect Bsal in our samples, but found widespread infection by Bd across central and northern Taiwan, both taxonomically and spatially. Museum samples show that Bd has been present in Taiwan since at least 1990. Host species, geography (elevation), climatic conditions and microbial richness were all associated with the prevalence of infection. Host life-history traits, skin microbiome composition and phylogeny were associated with lower prevalence of infection for high altitude species. Overall, we observed low prevalence and burden of infection in host populations, suggesting that Bd is enzootic in Taiwan where it causes subclinical infections. While amphibian species in Taiwan are currently threatened by habitat loss, our study indicates that Bd is in an endemic equilibrium with the populations and species we investigated. However, ongoing surveillance of the infection is warranted, as changing environmental conditions may disturb the currently stable equilibrium.
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Affiliation(s)
- Dirk S. Schmeller
- grid.15781.3a0000 0001 0723 035XLaboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, INPT, UPS, Toulouse, France
| | - Tina Cheng
- grid.263091.f0000000106792318Department of Biology, San Francisco State University, 1600 Holloway Ave, San Francisco, CA 94132 USA ,grid.421477.30000 0004 0639 1575Bat Conservation International, Washington, DC USA
| | - Jennifer Shelton
- grid.7445.20000 0001 2113 8111Department of Infectious Disease Epidemiology, Imperial College London, London, W2 1PG UK
| | - Chun-Fu Lin
- Zoology Division, Endemic Species Research Institute, Jiji, Nantou Taiwan, ROC
| | - Alan Chan-Alvarado
- grid.263091.f0000000106792318Department of Biology, San Francisco State University, 1600 Holloway Ave, San Francisco, CA 94132 USA
| | - Adriana Bernardo-Cravo
- grid.15781.3a0000 0001 0723 035XLaboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, INPT, UPS, Toulouse, France
| | - Luca Zoccarato
- grid.419247.d0000 0001 2108 8097Department of Experimental Limnology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Alte Fischerhütte 2, 16775 Stechlin, Germany
| | - Tzung-Su Ding
- grid.19188.390000 0004 0546 0241School of Forestry and Resource Conservation, National Taiwan University, Taipei City, 106 Taiwan, ROC
| | - Yu-Pin Lin
- grid.19188.390000 0004 0546 0241Department of Bioenvironmental Systems Engineering, National Taiwan University, Taipei, Taiwan, ROC
| | - Andrea Swei
- grid.263091.f0000000106792318Department of Biology, San Francisco State University, 1600 Holloway Ave, San Francisco, CA 94132 USA
| | - Matthew C. Fisher
- grid.7445.20000 0001 2113 8111Department of Infectious Disease Epidemiology, Imperial College London, London, W2 1PG UK
| | - Vance T. Vredenburg
- grid.263091.f0000000106792318Department of Biology, San Francisco State University, 1600 Holloway Ave, San Francisco, CA 94132 USA ,grid.47840.3f0000 0001 2181 7878Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, CA 94720 USA
| | - Adeline Loyau
- grid.15781.3a0000 0001 0723 035XLaboratoire Ecologie Fonctionnelle et Environnement, Université de Toulouse, INPT, UPS, Toulouse, France ,grid.419247.d0000 0001 2108 8097Department of Experimental Limnology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Alte Fischerhütte 2, 16775 Stechlin, Germany
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Levitt BB, Lai HC, Manville AM. Effects of non-ionizing electromagnetic fields on flora and fauna, Part 2 impacts: how species interact with natural and man-made EMF. REVIEWS ON ENVIRONMENTAL HEALTH 2022; 37:327-406. [PMID: 34243228 DOI: 10.1515/reveh-2021-0050] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 05/26/2021] [Indexed: 06/13/2023]
Abstract
Ambient levels of nonionizing electromagnetic fields (EMF) have risen sharply in the last five decades to become a ubiquitous, continuous, biologically active environmental pollutant, even in rural and remote areas. Many species of flora and fauna, because of unique physiologies and habitats, are sensitive to exogenous EMF in ways that surpass human reactivity. This can lead to complex endogenous reactions that are highly variable, largely unseen, and a possible contributing factor in species extinctions, sometimes localized. Non-human magnetoreception mechanisms are explored. Numerous studies across all frequencies and taxa indicate that current low-level anthropogenic EMF can have myriad adverse and synergistic effects, including on orientation and migration, food finding, reproduction, mating, nest and den building, territorial maintenance and defense, and on vitality, longevity and survivorship itself. Effects have been observed in mammals such as bats, cervids, cetaceans, and pinnipeds among others, and on birds, insects, amphibians, reptiles, microbes and many species of flora. Cyto- and geno-toxic effects have long been observed in laboratory research on animal models that can be extrapolated to wildlife. Unusual multi-system mechanisms can come into play with non-human species - including in aquatic environments - that rely on the Earth's natural geomagnetic fields for critical life-sustaining information. Part 2 of this 3-part series includes four online supplement tables of effects seen in animals from both ELF and RFR at vanishingly low intensities. Taken as a whole, this indicates enough information to raise concerns about ambient exposures to nonionizing radiation at ecosystem levels. Wildlife loss is often unseen and undocumented until tipping points are reached. It is time to recognize ambient EMF as a novel form of pollution and develop rules at regulatory agencies that designate air as 'habitat' so EMF can be regulated like other pollutants. Long-term chronic low-level EMF exposure standards, which do not now exist, should be set accordingly for wildlife, and environmental laws should be strictly enforced - a subject explored in Part 3.
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Affiliation(s)
| | - Henry C Lai
- Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - Albert M Manville
- Advanced Academic Programs, Krieger School of Arts and Sciences, Environmental Sciences and Policy, Johns Hopkins University, Washington DC Campus, USA
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Le Sage EH, Ohmer MEB, LaBumbard BC, Altman KA, Reinert LK, Bednark JG, Bletz MC, Inman B, Lindauer A, McDonnell NB, Parker SK, Skerlec SM, Wantman T, Rollins‐Smith LA, Woodhams DC, Voyles J, Richards‐Zawacki CL. Localized carry‐over effects of pond drying on survival, growth, and pathogen defenses in amphibians. Ecosphere 2022. [DOI: 10.1002/ecs2.4224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Emily H. Le Sage
- Department of Pathology, Microbiology and Immunology Vanderbilt University School of Medicine Nashville Tennessee USA
| | - Michel E. B. Ohmer
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | | | - Karie A. Altman
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Laura K. Reinert
- Department of Pathology, Microbiology and Immunology Vanderbilt University School of Medicine Nashville Tennessee USA
| | - Jeffery G. Bednark
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Molly C. Bletz
- Department of Biology University of Massachusetts Boston Massachusetts USA
| | - Brady Inman
- Department of Pathology, Microbiology and Immunology Vanderbilt University School of Medicine Nashville Tennessee USA
- Department of Biology University of Massachusetts Boston Massachusetts USA
| | - Alexa Lindauer
- Department of Biology University of Nevada Reno Nevada USA
| | - Nina B. McDonnell
- Department of Biology University of Massachusetts Boston Massachusetts USA
| | - Sadie K. Parker
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Samantha M. Skerlec
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Trina Wantman
- Department of Biological Sciences University of Pittsburgh Pittsburgh Pennsylvania USA
| | - Louise A. Rollins‐Smith
- Department of Pathology, Microbiology and Immunology Vanderbilt University School of Medicine Nashville Tennessee USA
- Department of Biological Sciences Vanderbilt University Nashville Tennessee USA
- Department of Pediatrics Vanderbilt University School of Medicine Nashville Tennessee USA
| | | | - Jamie Voyles
- Department of Biology University of Nevada Reno Nevada USA
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Federico Pablo K, Igor B, Juan Carlos A, Rodrigo A, María Gabriela A, Mauricio Sebastián A, María Luz A, Claudio A, Nadia Carla B, Graciela Mirta B, Rodrigo C, Andrés C, Valeria C, Claudio C, María Elena C, Camila D, Pietro Diego D, María Soledad G, Alés Rodrigo G, Camila K, Nicolás K, Gabriel L, Tomás Agustín M, Tomás MA, Marta M, Rodrigo NC, Hernán P, Juan Manuel PI, Kokot Lía P, Felipe R, Melina Jesús RM, Laura Cecilia S, Charif T, Carmen Ú, Marcos V, Melina Alicia V, Marcela V, Jorge Daniel W. Current threats faced by amphibian populations in the southern cone of south america. J Nat Conserv 2022. [DOI: 10.1016/j.jnc.2022.126254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Hase K. Microflora Influence: The Aquatic Environment Changes Grouping Risk and Development Speed of Toad Tadpoles. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.917067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In addition to habitat loss and fragmentation, behavioral traits and the deterioration of water environments also contribute to the local extinction of amphibians. Abundant microflora in urban ponds may cause fatal diseases, whereas symbiotic bacteria may protect the host from pathogens; these effects may vary with group size. In this study, I monitored the growth of Japanese common toad (Bufo japonicus) larvae in Tokyo using three different group sizes: 1 (solitary), 2 (pair), and 15. Although there was no genetic bias in the major histocompatibility complex (MHC) class II genes or microsatellite loci to the survival of the larvae, the mortality risk of the larvae reared in pond water was higher than that of those reared in tap water. According to the survival analysis, the risk was more significant when the group size was 15. This result would be unwelcomed for the B. japonicus tadpoles, which have habits of social aggregation. Furthermore, larval metamorphosis took longer to complete in pond than tap water without any difference in body length or mass. These findings provide fundamental insight into the impact of the aquatic environment and the effect of the group size on animal health and conservation.
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García-Sánchez JC, Arredondo-Centeno J, Segovia-Ramírez MG, Tenorio Olvera AM, Parra-Olea G, Vredenburg VT, Rovito SM. Factors Influencing Bacterial and Fungal Skin Communities of Montane Salamanders of Central Mexico. MICROBIAL ECOLOGY 2022:10.1007/s00248-022-02049-x. [PMID: 35705744 DOI: 10.1007/s00248-022-02049-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 05/20/2022] [Indexed: 06/15/2023]
Abstract
Host microbial communities are increasingly seen as an important component of host health. In amphibians, the first land vertebrates that are threatened by a fungal skin disease globally, our understanding of the factors influencing the microbiome of amphibian skin remains incomplete because recent studies have focused almost exclusively on bacteria, and little information exists on fungal communities associated with wild amphibian species. In this study, we describe the effects of host phylogeny, climate, geographic distance, and infection with a fungal pathogen on the composition and structure of bacterial and fungal communities in seven tropical salamander species that occur in the Trans-Mexican Volcanic Belt of Central Mexico. We find that host phylogenetic relatedness is correlated with bacterial community composition while a composite climatic variable of temperature seasonality and precipitation is significantly associated with fungal community composition. We also estimated co-occurrence networks for bacterial and fungal taxa and found differences in the degree of connectivity and the distribution of negative associations between the two networks. Our results suggest that different factors may be responsible for structuring the bacterial and fungal communities of amphibian skin and that the inclusion of fungi in future studies could shed light on important functional interactions within the microbiome.
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Affiliation(s)
- Julio César García-Sánchez
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México
| | - José Arredondo-Centeno
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México
- Instituto Tecnológico Superior de Irapuato, Irapuato, Guanajuato, México
| | - María Guadalupe Segovia-Ramírez
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México
| | - Ariadna Marcela Tenorio Olvera
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México
- Instituto Tecnológico Superior de Irapuato, Irapuato, Guanajuato, México
| | - Gabriela Parra-Olea
- Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de Mexico, México
| | - Vance T Vredenburg
- Department of Biology, San Francisco State University, San Francisco, CA, USA
- Museum of Vertebrate Zoology, University of California, Berkeley, CA, USA
| | - Sean M Rovito
- Unidad de Genómica Avanzada, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Guanajuato, México.
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Costa S, Lopes I. Saprolegniosis in Amphibians: An Integrated Overview of a Fluffy Killer Disease. J Fungi (Basel) 2022; 8:jof8050537. [PMID: 35628794 PMCID: PMC9144230 DOI: 10.3390/jof8050537] [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: 01/12/2022] [Revised: 05/07/2022] [Accepted: 05/09/2022] [Indexed: 12/04/2022] Open
Abstract
Amphibians constitute the class of vertebrates with the highest proportion of threatened species, with infectious diseases being considered among the greatest causes for their worldwide decline. Aquatic oomycetes, known as “water molds,” are fungus-like microorganisms that are ubiquitous in freshwater ecosystems and are capable of causing disease in a broad range of amphibian hosts. Various species of Achlya sp., Leptolegnia sp., Aphanomyces sp., and mainly, Saprolegnia sp., are responsible for mass die-offs in the early developmental stages of a wide range of amphibian populations through a disease known as saprolegniosis, aka, molding or a “Saprolegnia-like infection.” In this context, the main objective of the present review was to bring together updated information about saprolegniosis in amphibians to integrate existing knowledge, identify current knowledge gaps, and suggest future directions within the saprolegniosis–amphibian research field. Based on the available literature and data, an integrated and critical interpretation of the results is discussed. Furthermore, the occurrence of saprolegniosis in natural and laboratory contexts and the factors that influence both pathogen incidence and host susceptibility are also addressed. The focus of this work was the species Saprolegnia sp., due to its ecological importance on amphibian population dynamics and due to the fact that this is the most reported genera to be associated with saprolegniosis in amphibians. In addition, integrated emerging therapies, and their potential application to treat saprolegniosis in amphibians, were evaluated, and future actions are suggested.
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Kim TY, Baldrias L, Papageorgiou S, Aguilar E, Tee M, Kelly T, Hill J, Wilkes M. A community-based survey to assess risk for one health challenges in rural Philippines using a mobile application. ONE HEALTH OUTLOOK 2022; 4:7. [PMID: 35379343 PMCID: PMC8979641 DOI: 10.1186/s42522-022-00063-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Recent emerging and re-emerging diseases in animals and humans show the vulnerability of humans, animals, and crops to disease outbreaks and the large potential impact on health, food security, and economies worldwide. A technology-enabled One Health (OH) surveillance program offers an opportunity for early detection and response as well as prevention of disease outbreaks in resource-limited settings. As an initial step toward developing the surveillance program, we aimed to identify at-risk groups of households for potential shared health challenges at the human-animal-environmental interface in a rural community of the Philippines. METHODS A cross-sectional household survey was conducted in the municipality of Los Baños in proximity (63 kilometers south) to Metro Manila by enumerators living in the same community. Twenty-four enumerators conducted household interviews asking a) household characteristics including ownership of animals and crops; b) awareness, beliefs and knowledge about OH; c) family-level health practices related to sanitation, hygiene, and food safety; and d) risk factors for potential OH issues. All data collection and transferring process were streamlined using a mobile application. RESULTS Of 6,055 participating households, 68% reported having one or more of gardens, farms, and animals for various reasons. While only 2% of the households have heard about OH, 97% believed they can get disease from animals, plants or the environment. A latent class analysis with nine risk factors for potential OH issues suggested that 46% of the households were at moderate to high risk for exposure to zoonotic pathogens and environmental contaminants. CONCLUSION Our findings indicate that there are unaddressed threats to human, animal, and plant health. Given the importance of the interconnections between the health of humans, animals, and plants, further evaluations of the at-risk households would be necessary to mitigate potential shared health threats in the community. Further, our study demonstrates that mHealth technology can provide an opportunity to systematically assess potential one health problems in the rural communities with limited internet connection.
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Affiliation(s)
- Tae Youn Kim
- Betty Irene Moore School of Nursing, University of California Davis, 2450 48th Street, Suite 2600, Sacramento, CA, 95817, USA.
| | - Loinda Baldrias
- College of Veterinary Medicine, University of the Philippines, Los Baños, Laguna, Philippines
| | - Sophia Papageorgiou
- One Health Institute, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - Edna Aguilar
- College of Agriculture and Food Science, University of the Philippines, Los Baños, Laguna, Philippines
| | - Michael Tee
- College of Medicine, University of the Philippines, Manila, Philippines
| | - Terra Kelly
- One Health Institute, School of Veterinary Medicine, University of California Davis, Davis, CA, USA
| | - Jim Hill
- College of Agriculture and Environmental Sciences, University of California Davis, Davis, CA, USA
| | - Michael Wilkes
- School of Medicine, University of California Davis, Sacramento, CA, USA
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Saeed M, Rais M, Akram A, Williams MR, Kellner KF, Hashsham SA, Davis DR. Development and validation of an eDNA protocol for monitoring endemic Asian spiny frogs in the Himalayan region of Pakistan. Sci Rep 2022; 12:5624. [PMID: 35379841 PMCID: PMC8979970 DOI: 10.1038/s41598-022-09084-1] [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: 11/13/2021] [Accepted: 03/17/2022] [Indexed: 11/09/2022] Open
Abstract
Wildlife monitoring programs are instrumental for the assessment of species, habitat status, and for the management of factors affecting them. This is particularly important for species found in freshwater ecosystems, such as amphibians, as they have higher estimated extinction rates than terrestrial species. We developed and validated two species-specific environmental DNA (eDNA) protocols and applied them in the field to detect the Hazara Torrent Frog (Allopaa hazarensis) and Murree Hills Frog (Nanorana vicina). Additionally, we compared eDNA surveys with visual encounter surveys and estimated site occupancy. eDNA surveys resulted in higher occurrence probabilities for both A. hazarensis and N. vicina than for visual encounter surveys. Detection probability using eDNA was greater for both species, particularly for A. hazarensis. The top-ranked detection model for visual encounter surveys included effects of both year and temperature on both species, and the top-ranked occupancy model included effects of elevation and year. The top-ranked detection model for eDNA data was the null model, and the top-ranked occupancy model included effects of elevation, year, and wetland type. To our knowledge, this is the first time an eDNA survey has been used to monitor amphibian species in the Himalayan region.
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Affiliation(s)
- Muhammad Saeed
- Herpetology Lab, Department of Wildlife Management, Faculty of Forestry, Range Management and Wildlife, Pir Mehr Ali Shah, Arid Agriculture University Rawalpindi, Rawalpindi, 46000, Pakistan. .,Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI, USA.
| | - Muhammad Rais
- Herpetology Lab, Department of Wildlife Management, Faculty of Forestry, Range Management and Wildlife, Pir Mehr Ali Shah, Arid Agriculture University Rawalpindi, Rawalpindi, 46000, Pakistan.
| | - Ayesha Akram
- Herpetology Lab, Department of Wildlife Management, Faculty of Forestry, Range Management and Wildlife, Pir Mehr Ali Shah, Arid Agriculture University Rawalpindi, Rawalpindi, 46000, Pakistan
| | - Maggie R Williams
- School of Engineering and Technology, Institute for Great Lakes Research, Central Michigan University, Mount Pleasant, MI, USA
| | - Kenneth F Kellner
- Global Wildlife Conservation Center, State University of New York College of Environmental Science and Forestry, Syracuse, NY, USA
| | - Syed A Hashsham
- Department of Civil and Environmental Engineering, Michigan State University, East Lansing, MI, USA.,Center for Microbial Ecology, Michigan State University, East Lansing, MI, USA.,Department of Plant, Soil, and Microbial Sciences, Michigan State University, East Lansing, MI, USA
| | - Drew R Davis
- School of Earth, Environmental, and Marine Science, The University of Texas Rio Grande Valley, Brownsville, TX, USA.,Biodiversity Collections, Department of Integrative Biology, The University of Texas at Austin, Austin, TX, USA
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Haver M, Le Roux G, Friesen J, Loyau A, Vredenburg VT, Schmeller DS. The role of abiotic variables in an emerging global amphibian fungal disease in mountains. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 815:152735. [PMID: 34974000 DOI: 10.1016/j.scitotenv.2021.152735] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 12/23/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
The emergence of the chytridiomycete fungal pathogen Batrachochytrium dendrobatidis (Bd), causing the disease chytridiomycosis, has caused collapse of amphibian communities in numerous mountain systems. The health of amphibians and of mountain freshwater habitats they inhabit is also threatened by ongoing changes in environmental and anthropogenic factors such as climate, hydrology, and pollution. Climate change is causing more extreme climatic events, shifts in ice occurrence, and changes in the timing of snowmelt and pollutant deposition cycles. All of these factors impact both pathogen and host, and disease dynamics. Here we review abiotic variables, known to control Bd occurrence and chytridiomycosis severity, and discuss how climate change may modify them. We propose two main categories of abiotic variables that may alter Bd distribution, persistence, and physiology: 1) climate and hydrology (temperature, precipitation, hydrology, ultraviolet radiation (UVR); and, 2) water chemistry (pH, salinity, pollution). For both categories, we identify topics for further research. More studies on the relationship between global change, pollution and pathogens in complex landscapes, such as mountains, are needed to allow for accurate risk assessments for freshwater ecosystems and resulting impacts on wildlife and human health. Our review emphasizes the importance of using data of higher spatiotemporal resolution and uniform abiotic metrics in order to better compare study outcomes. Fine-scale temperature variability, especially of water temperature, variability of moisture conditions and water levels, snow, ice and runoff dynamics should be assessed as abiotic variables shaping the mountain habitat of pathogen and host. A better understanding of hydroclimate and water chemistry variables, as co-factors in disease, will increase our understanding of chytridiomycosis dynamics.
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Affiliation(s)
- Marilen Haver
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse INP, Université Toulouse 3 - Paul Sabatier (UPS), Toulouse, France.
| | - Gaël Le Roux
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse INP, Université Toulouse 3 - Paul Sabatier (UPS), Toulouse, France
| | - Jan Friesen
- Environmental and Biotechnology Centre, Helmholtz Centre for Environmental Research - UFZ, Leipzig, Germany
| | - Adeline Loyau
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse INP, Université Toulouse 3 - Paul Sabatier (UPS), Toulouse, France; Department of Experimental Limnology, Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Alte Fischerhütte 2, Stechlin D-16775, Germany
| | - Vance T Vredenburg
- Department of Biology, San Francisco State University, 1600 Holloway Ave., San Francisco, CA 94132, USA
| | - Dirk S Schmeller
- Laboratoire Écologie Fonctionnelle et Environnement, Université de Toulouse, CNRS, Toulouse INP, Université Toulouse 3 - Paul Sabatier (UPS), Toulouse, France
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Zhang L, Liu G, Xia T, Yang X, Sun G, Zhao C, Xu C, Zhang H. Evolution of toll-like receptor gene family in amphibians. Int J Biol Macromol 2022; 208:463-474. [PMID: 35337917 DOI: 10.1016/j.ijbiomac.2022.03.112] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Revised: 02/09/2022] [Accepted: 03/17/2022] [Indexed: 12/24/2022]
Abstract
The evolutionary position and lifestyle of amphibians highlights the important roles of the immune system in adaptive radiation and their adaptation to a complex pathogenic environment. Toll-like receptors (TLRs) are membrane-like sensors that recognize and bind conserved molecular motifs in pathogens to initiate downstream immune responses. To understand the evolutionary patterns of TLRs in amphibians, we analyzed TLR genes from the genomes and transcriptomes of 102 amphibian species. Phylogenetic results showed that 578 intact amphibian TLR sequences belonged to 16 TLR genes and were divided into seven subfamilies. The TLR4 subfamily was only identified in the Anura. Purification selection plays a leading role in amphibian TLR evolution and mean ω (dN/dS) values ranged from 0.252 for TLR7 to 0.381 for TLR19. Furthermore, the ω values of different domains were significantly different. We found positive selection patterns for 141 of 12,690 codons (1.1%) in all amphibian TLRs, most of which were located in leucine-rich repeats (LRRs). We also observed low to moderate levels of single-nucleotide polymorphisms (SNPs) in Pelophylax nigromaculatus and Bombina orientalis. This study provided critical primers, meaningful information regarding TLR gene family evolution in amphibians, and insights into the complex evolutionary patterns and implications of TLR polymorphisms.
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Affiliation(s)
- Lei Zhang
- College of Life Science, Qufu Normal University, Qufu, Shandong 273165, China
| | - Guangshuai Liu
- College of Life Science, Qufu Normal University, Qufu, Shandong 273165, China
| | - Tian Xia
- College of Life Science, Qufu Normal University, Qufu, Shandong 273165, China
| | - Xiufeng Yang
- College of Life Science, Qufu Normal University, Qufu, Shandong 273165, China
| | - Guolei Sun
- College of Life Science, Qufu Normal University, Qufu, Shandong 273165, China
| | - Chao Zhao
- College of Life Science, Qufu Normal University, Qufu, Shandong 273165, China
| | - Chunzhu Xu
- College of Life Science, Northeast Agricultural University, Harbin 150030, China.
| | - Honghai Zhang
- College of Life Science, Qufu Normal University, Qufu, Shandong 273165, China.
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Manenti R, Mercurio S, Melotto A, Barzaghi B, Epis S, Tecilla M, Pennati R, Scarì GU, Ficetola GF. A New Disease Caused by an Unidentified Etiological Agent Affects European Salamanders. Animals (Basel) 2022; 12:ani12060696. [PMID: 35327092 PMCID: PMC8944795 DOI: 10.3390/ani12060696] [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: 02/10/2022] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 02/04/2023] Open
Abstract
New pathologies are causing dramatic declines and extinctions of multiple amphibian species. In 2013, in one fire salamander population of Northern Italy, we found individuals with undescribed cysts at the throat level, a malady whose existence has not previously been reported in amphibians. With the aim of describing this novel disease, we performed repeated field surveys to assess the frequency of affected salamanders from 2014 to 2020, and integrated morphological, histological, and molecular analyses to identify the pathogen. The novel disease affected up to 22% of salamanders of the study population and started spreading to nearby populations. Cysts are formed by mucus surrounding protist-like cells about 30 µm long, characterized by numerous cilia/undulipodia. Morphological and genetic analyses did not yield a clear match with described organisms. The existence of this pathogen calls for the implementation of biosecurity protocols and more studies on the dynamics of transmission and the impact on wild populations.
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Affiliation(s)
- Raoul Manenti
- Department of Environmental Science and Policy, University of Milano, 20133 Milano, Italy; (B.B.); (R.P.); (G.F.F.)
- Correspondence: (R.M.); (S.M.); Tel.: +39-3490733107 (R.M.)
| | - Silvia Mercurio
- Department of Environmental Science and Policy, University of Milano, 20133 Milano, Italy; (B.B.); (R.P.); (G.F.F.)
- Correspondence: (R.M.); (S.M.); Tel.: +39-3490733107 (R.M.)
| | - Andrea Melotto
- Centre of Excellence for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Stellenbosch 7602, South Africa;
| | - Benedetta Barzaghi
- Department of Environmental Science and Policy, University of Milano, 20133 Milano, Italy; (B.B.); (R.P.); (G.F.F.)
| | - Sara Epis
- Department of Biosciences, University of Milano, 20133 Milano, Italy; (S.E.); (M.T.); (G.U.S.)
| | - Marco Tecilla
- Department of Biosciences, University of Milano, 20133 Milano, Italy; (S.E.); (M.T.); (G.U.S.)
| | - Roberta Pennati
- Department of Environmental Science and Policy, University of Milano, 20133 Milano, Italy; (B.B.); (R.P.); (G.F.F.)
| | - Giorgio Ulisse Scarì
- Department of Biosciences, University of Milano, 20133 Milano, Italy; (S.E.); (M.T.); (G.U.S.)
| | - Gentile Francesco Ficetola
- Department of Environmental Science and Policy, University of Milano, 20133 Milano, Italy; (B.B.); (R.P.); (G.F.F.)
- Laboratoire d’Ecologie Alpine (LECA), University Grenoble Alpes, CNRS, 38400 Grenoble, France
- Laboratoire d’Ecologie Alpine (LECA), University Savoie Mont Blanc, CNRS, 38400 Grenoble, France
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Wetsch O, Strasburg M, McQuigg J, Boone MD. Is overwintering mortality driving enigmatic declines? Evaluating the impacts of trematodes and the amphibian chytrid fungus on an anuran from hatching through overwintering. PLoS One 2022; 17:e0262561. [PMID: 35030210 PMCID: PMC8759641 DOI: 10.1371/journal.pone.0262561] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Accepted: 12/30/2021] [Indexed: 11/23/2022] Open
Abstract
Emerging infectious diseases are increasing globally and are an additional challenge to species dealing with native parasites and pathogens. Therefore, understanding the combined effects of infectious agents on hosts is important for species’ conservation and population management. Amphibians are hosts to many parasites and pathogens, including endemic trematode flatworms (e.g., Echinostoma spp.) and the novel pathogenic amphibian chytrid fungus (Batrachochytrium dendrobatidis [Bd]). Our study examined how exposure to trematodes during larval development influenced the consequences of Bd pathogen exposure through critical life events. We found that prior exposure to trematode parasites negatively impacted metamorphosis but did not influence the effect of Bd infection on terrestrial growth and survival. Bd infection alone, however, resulted in significant mortality during overwintering—an annual occurrence for most temperate amphibians. The results of our study indicated overwintering mortality from Bd could provide an explanation for enigmatic declines and highlights the importance of examining the long-term consequences of novel parasite exposure.
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Affiliation(s)
- Olivia Wetsch
- Department of Biology, Miami University, Oxford, Ohio, United States of America
- * E-mail:
| | - Miranda Strasburg
- Department of Biology, Miami University, Oxford, Ohio, United States of America
| | - Jessica McQuigg
- Department of Biology, Miami University, Oxford, Ohio, United States of America
| | - Michelle D. Boone
- Department of Biology, Miami University, Oxford, Ohio, United States of America
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Penczykowski RM, Shocket MS, Ochs JH, Lemanski BCP, Sundar H, Duffy MA, Hall SR. Virulent Disease Epidemics Can Increase Host Density by Depressing Foraging of Hosts. Am Nat 2022; 199:75-90. [DOI: 10.1086/717175] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Palomar G, Jakóbik J, Bosch J, Kolenda K, Kaczmarski M, Jośko P, Roces-Díaz JV, Stachyra P, Thumsová B, Zieliński P, Pabijan M. Emerging infectious diseases of amphibians in Poland: distribution and environmental drivers. DISEASES OF AQUATIC ORGANISMS 2021; 147:1-12. [PMID: 34734569 DOI: 10.3354/dao03631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Emerging infectious diseases are a threat to biodiversity and have taken a large toll on amphibian populations worldwide. The chytrid fungi Batrachochytrium dendrobatidis (Bd) and B. salamandrivorans (Bsal), and the iridovirus Ranavirus (Rv), are of concern as all have contributed to amphibian declines. In central and eastern Europe, their geographical and host distributions and main environmental drivers determining prevalence are poorly known. We screened over 1000 amphibians from natural and captive populations in Poland for the presence of Bd, Bsal and Rv. In wild amphibian populations, we found that Bd is widespread, present in 46 out of 115 sampled localities as well as 2 captive colonies, and relatively common with overall prevalence at 14.4% in 9 species. We found lower prevalence of Rv at 2.4%, present in 11 out of 92 sampling sites, with a taxonomic breadth of 8 different amphibian species. Bsal infection was not detected in any individuals. In natural populations, Pelophylax esculentus and Bombina variegata accounted for 75% of all Bd infections, suggesting a major role for these 2 species as pathogen reservoirs in Central European freshwater habitats. General linear models showed that climatic as well as landscape features are associated with Bd infection in Poland. We found that higher average annual temperature constrains Bd infection, while landscapes with numerous water bodies or artificial elements (a surrogate for urbanization) increase the chances of infection. Our results show that a combination of climatic and landscape variables may drive regional and local pathogen emergence.
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Affiliation(s)
- Gemma Palomar
- Institute of Environmental Sciences, Faculty of Biology, Jagiellonian University, Gronostajowa 7, 30-387 Kraków, Poland
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Holt WV, Comizzoli P. Opportunities and Limitations for Reproductive Science in Species Conservation. Annu Rev Anim Biosci 2021; 10:491-511. [PMID: 34699258 DOI: 10.1146/annurev-animal-013120-030858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Reproductive science in the context of conservation biology is often understood solely in terms of breeding threatened species. Although technologies developed primarily for agriculture or biomedicine have a potentially important role in species conservation, their effectiveness is limited if we regard the main objective of animal conservation as helping to support populations rather than to breed a small number of individuals. The global threats facing wild species include the consequences of climate change, population growth, urbanization, atmospheric and water pollution, and the release of chemicals into the environment, to cite but a few. Reproductive sciences provide important and often unexpected windows into many of these consequences, and our aim here is both to demonstrate the breadth of reproductive science and the importance of basic knowledge and to suggest where some of the insights might be useful in mitigating the problems. Expected final online publication date for the Annual Review of Animal Biosciences, Volume 10 is February 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- William V Holt
- Academic Unit of Reproductive and Developmental Medicine, Department of Oncology & Metabolism, University of Sheffield, Sheffield, United Kingdom;
| | - Pierre Comizzoli
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, USA;
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Goodman RM, Carter ED, Miller DL. Influence of Herbicide Exposure and Ranavirus Infection on Growth and Survival of Juvenile Red-Eared Slider Turtles ( Trachemys scripta elegans). Viruses 2021; 13:1440. [PMID: 34452306 PMCID: PMC8402795 DOI: 10.3390/v13081440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 07/14/2021] [Accepted: 07/19/2021] [Indexed: 11/16/2022] Open
Abstract
Ranaviruses are an important wildlife pathogen of fish, amphibians, and reptiles. Previous studies have shown that susceptibility and severity of infection can vary with age, host species, virus strain, temperature, population density, and presence of environmental stressors. Experiments are limited with respect to interactions between this pathogen and environmental stressors in reptiles. In this study, we exposed hatchling red-eared slider turtles (Trachemys scripta elegans) to herbicide and ranavirus treatments to examine direct effects and interactions on growth, morbidity, and mortality. Turtles were assigned to one of three herbicide treatments or a control group. Turtles were exposed to atrazine, Roundup ProMax®, or Rodeo® via water bath during the first 3 weeks of the experiment. After 1 week, turtles were exposed to either a control (cell culture medium) or ranavirus-infected cell lysate via injection into the pectoral muscles. Necropsies were performed upon death or upon euthanasia after 5 weeks. Tissues were collected for histopathology and detection of ranavirus DNA via quantitative PCR. Only 57.5% of turtles exposed to ranavirus tested positive for ranaviral DNA at the time of death. Turtles exposed to ranavirus died sooner and lost more mass and carapace length, but not plastron length, than did controls. Exposure to environmentally relevant concentrations of herbicides did not impact infection rate, morbidity, or mortality of hatchling turtles due to ranavirus exposure. We also found no direct effects of herbicide or interactions with ranavirus exposure on growth or survival time. Results of this study should be interpreted in the context of the modest ranavirus infection rate achieved, the general lack of growth, and the unplanned presence of an additional pathogen in our study.
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Affiliation(s)
- Rachel M. Goodman
- Biology Department, Hampden-Sydney College, Hampden-Sydney, VA 23943, USA
| | - Edward Davis Carter
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN 37996, USA; (E.D.C.); (D.L.M.)
| | - Debra L. Miller
- Center for Wildlife Health, University of Tennessee Institute of Agriculture, Knoxville, TN 37996, USA; (E.D.C.); (D.L.M.)
- Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996, USA
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The Occurrence of Ophidiomyces ophiodiicola in Northern Georgia Wild and Captive Snake Populations. J Wildl Dis 2021; 57:643-647. [PMID: 33978750 DOI: 10.7589/jwd-d-20-00129] [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: 07/15/2020] [Accepted: 10/24/2020] [Indexed: 11/20/2022]
Abstract
Ophidiomycosis, or snake fungal disease, is an emerging wildlife disease caused by the Ophidiomyces ophiodiicola fungus. The fungus can result in high mortality rates among infected snakes and has been documented across much of the eastern US, including southern Georgia. However, little is known about ophidiomycosis in northern Georgia. We surveyed wild snake populations in five counties of northern Georgia between March 2019 and March 2020 and swabbed captured snakes (n=27) for the presence of O. ophiodiicola DNA. We followed similar sampling protocols with a group of captive snakes (n=6) at the Elachee Nature Center in Hall County, Georgia. Quantitative PCR confirmed the presence of O. ophiodiicola DNA in 33% (11/33) of snakes. Eight of the confirmed positive samples were collected from wild snakes (30%, 8/27) across our sample region, while three were from our captive group (50%, 3/6). Our results indicated that O. ophiodiicola is present in wild snake populations in northern Georgia, and the pathogen is present in seemingly healthy captive snakes. This knowledge is critical for conservation and management efforts, but more research is needed to fully understand ophidiomycosis and its effect on snake populations in the region.
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Ujszegi J, Ludányi K, Móricz ÁM, Krüzselyi D, Drahos L, Drexler T, Németh MZ, Vörös J, Garner TWJ, Hettyey A. Exposure to Batrachochytrium dendrobatidis affects chemical defences in two anuran amphibians, Rana dalmatina and Bufo bufo. BMC Ecol Evol 2021; 21:135. [PMID: 34217227 PMCID: PMC8254444 DOI: 10.1186/s12862-021-01867-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 06/23/2021] [Indexed: 11/03/2022] Open
Abstract
Background Batrachochytrium dendrobatidis (Bd) is the causative agent of chytridiomycosis, one of the major causes of worldwide amphibian biodiversity loss. Many amphibians exhibit skin-based chemical defences, which may play an important role against invading pathogens, but whether the synthesis of these chemical compounds is enhanced or suppressed in the presence of pathogens is largely unknown. Here we investigated direct and indirect effects of larval exposure to the globally distributed and highly virulent Bd-GPL strain on skin secreted chemical defences and life history traits during early ontogeny of agile frogs (Rana dalmatina) and common toads (Bufo bufo). Results Exposure to Bd during the larval stage did not result in enhanced synthesis of the antimicrobial peptide Brevinin-1 Da in R. dalmatina tadpoles or in increased production of bufadienolides in B. bufo tadpoles. However, exposure to Bd during the larval stage had a carry-over effect reaching beyond metamorphosis: both R. dalmatina and B. bufo froglets contained smaller quantities of defensive chemicals than their Bd-naïve conspecifics in the control treatment. Prevalence of Bd and infection intensities were very low in both larvae and metamorphs of R. dalmatina, while in B. bufo we observed high Bd prevalence and infection intensities, especially in metamorphs. At the same time, we did not find a significant effect of Bd-exposure on body mass or development rate in larvae or metamorphs in either species. Conclusions The lack of detrimental effect of Bd-exposure on life history traits, even parallel with high infection intensities in the case of B. bufo individuals, is surprising and suggests high tolerance of local populations of these two species against Bd. However, the lowered quantity of defensive chemicals may compromise antimicrobial and antipredatory defences of froglets, which may ultimately contribute to population declines also in the absence of conspicuous mass-mortality events.
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Affiliation(s)
- János Ujszegi
- Lendület Evolutionary Ecology Research Group, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary.
| | - Krisztina Ludányi
- Department of Pharmaceutics, Faculty of Pharmacy, Semmelweis University, Hőgyes Endre utca 7, Budapest, 1092, Hungary
| | - Ágnes M Móricz
- Department of Pathophysiology, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary
| | - Dániel Krüzselyi
- Department of Pathophysiology, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary
| | - László Drahos
- MS Proteomics Research Group, Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest, 1117, Hungary
| | - Tamás Drexler
- Lendület Evolutionary Ecology Research Group, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary.,Department of Ecology, Institute for Biology, University of Veterinary Medicine, Rottenbiller utca 50, Budapest, 1077, Hungary
| | - Márk Z Németh
- Department of Plant Pathology, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary
| | - Judit Vörös
- Department of Zoology, Hungarian Natural History Museum, Baross street 13, Budapest, 1088, Hungary
| | - Trenton W J Garner
- Institute of Zoology, Zoological Society of London, Regent's Park, London, NW1 4RY, UK.,Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
| | - Attila Hettyey
- Lendület Evolutionary Ecology Research Group, Plant Protection Institute, Centre for Agricultural Research, Herman Ottó út 15, Budapest, 1022, Hungary.,Department of Ecology, Institute for Biology, University of Veterinary Medicine, Rottenbiller utca 50, Budapest, 1077, Hungary
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Host genotype and genetic diversity shape the evolution of a novel bacterial infection. THE ISME JOURNAL 2021; 15:2146-2157. [PMID: 33603148 PMCID: PMC8245636 DOI: 10.1038/s41396-021-00911-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 01/10/2021] [Accepted: 01/25/2021] [Indexed: 01/31/2023]
Abstract
Pathogens continue to emerge from increased contact with novel host species. Whilst these hosts can represent distinct environments for pathogens, the impacts of host genetic background on how a pathogen evolves post-emergence are unclear. In a novel interaction, we experimentally evolved a pathogen (Staphylococcus aureus) in populations of wild nematodes (Caenorhabditis elegans) to test whether host genotype and genetic diversity affect pathogen evolution. After ten rounds of selection, we found that pathogen virulence evolved to vary across host genotypes, with differences in host metal ion acquisition detected as a possible driver of increased host exploitation. Diverse host populations selected for the highest levels of pathogen virulence, but infectivity was constrained, unlike in host monocultures. We hypothesise that population heterogeneity might pool together individuals that contribute disproportionately to the spread of infection or to enhanced virulence. The genomes of evolved populations were sequenced, and it was revealed that pathogens selected in distantly-related host genotypes diverged more than those in closely-related host genotypes. S. aureus nevertheless maintained a broad host range. Our study provides unique empirical insight into the evolutionary dynamics that could occur in other novel infections of wildlife and humans.
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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: 1] [Impact Index Per Article: 0.3] [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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Eleftheriou A, Kuenzi AJ, Luis AD. Heterospecific competitors and seasonality can affect host physiology and behavior: key factors in disease transmission. Ecosphere 2021. [DOI: 10.1002/ecs2.3494] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Andreas Eleftheriou
- Wildlife Biology Program University of Montana 32 Campus Drive, FOR 109 Missoula Montana59812USA
| | - Amy J. Kuenzi
- Department of Biology Montana Tech of the University of Montana Butte Montana59701USA
| | - Angela D. Luis
- Wildlife Biology Program University of Montana 32 Campus Drive, FOR 109 Missoula Montana59812USA
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TLR5-Mediated Reactivation of Quiescent Ranavirus FV3 in Xenopus Peritoneal Macrophages. J Virol 2021; 95:JVI.00215-21. [PMID: 33827949 DOI: 10.1128/jvi.00215-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 03/28/2021] [Indexed: 12/25/2022] Open
Abstract
Ranaviruses such as frog virus 3 (FV3) are large double-stranded DNA (dsDNA) viruses causing emerging infectious diseases leading to extensive morbidity and mortality of amphibians and other ectothermic vertebrates worldwide. Among the hosts of FV3, some are highly susceptible, whereas others are resistant and asymptomatic carriers that can take part in disseminating the infectious virus. To date, the mechanisms involved in the processes of FV3 viral persistence associated with subclinical infection transitioning to lethal outbreaks remain unknown. Investigation in Xenopus laevis has revealed that in asymptomatic FV3 carrier animals, inflammation induced by heat-killed (HK) Escherichia coli stimulation can provoke the relapse of active infection. Since Toll-like receptors (TLRs) are critical for recognizing microbial molecular patterns, we investigated their possible involvement in inflammation-induced FV3 reactivation. Among the 10 different TLRs screened for changes in expression levels following FV3 infection and HK E. coli stimulation, only TLR5 and TLR22, both of which recognize bacterial products, showed differential expression, and only the TLR5 ligand flagellin was able to induce FV3 reactivation similarly to HK E. coli Furthermore, only the TLR5 ligand flagellin induced FV3 reactivation in peritoneal macrophages both in vitro and in vivo These data indicate that the TLR5 signaling pathway can trigger FV3 reactivation and suggest a role of secondary bacterial infections or microbiome alterations (stress or pollution) in initiating sudden deadly disease outbreaks in amphibian populations with detectable persistent asymptomatic ranavirus.IMPORTANCE This study in the amphibian Xenopus laevis provides new evidence of the critical role of macrophages in the persistence of ranaviruses in a quiescent state as well as in the reactivation of these pathogens into a virulent infection. Among the multiple microbial sensors expressed by macrophages, our data underscore the preponderant involvement of TLR5 stimulation in triggering the reactivation of quiescent FV3 in resident peritoneal macrophages, unveiling a mechanistic connection between the reactivation of persisting ranavirus infection and bacterial coinfection. This suggests a role for secondary bacterial infections or microbiome alterations (stress or pollution) in initiating sudden deadly disease outbreaks in amphibian populations with detectable persistent asymptomatic ranavirus.
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Abstract
AbstractFrogs have been harvested from the wild for the last 40 years in Turkey. We analysed the population dynamics of Anatolian water frogs (Pelophylax spp.) in the Seyhan and Ceyhan Deltas during 2013–2015. We marked a total of 13,811 individuals during 3 years, estimated population sizes, simulated the dynamics of a harvested population over 50 years, and collated frog harvest and export statistics from the region and for Turkey as a whole. Our capture estimates indicated a population reduction of c. 20% per year, and our population modelling showed that, if overharvesting continues at current rates, the harvested populations will decline rapidly. Simulations with a model of harvested population dynamics resulted in a risk of extinction of > 90% within 50 years, with extinction likely in c. 2032. Our interviews with harvesters revealed their economic dependence on the frog harvest. However, our results also showed that reducing harvest rates would not only ensure the viability of these frog populations but would also provide a source of income that is sustainable in the long term. Our study provides insights into the position of Turkey in the ‘extinction domino’ line, in which harvest pressure shifts among countries as frog populations are depleted and harvest bans are effected. We recommend that harvesting of wild frogs should be banned during the mating season, hunting and exporting of frogs < 30 g should be banned, and harvesters should be trained on species knowledge and awareness of regulations.
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Trojan hosts: the menace of invasive vertebrates as vectors of pathogens in the Southern Cone of South America. Biol Invasions 2021. [DOI: 10.1007/s10530-021-02488-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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