Worrying news for brazilian caatinga : prevalence of batrachochytrium dendrobatidis in amphibians

The chytrid fungus Batrachochytrium dendrobatidis (Bd) has been linked to the declines of more than 500 amphibian species globally. In Brazil, Bd has been identified in several regions but predominantly in the Atlantic Forest. Data on the occurrence of this amphibian pathogen in northeastern Brazil are scarce, specifically from the Caatinga ecoregion, where there is only one study that reports Bd in the region. This study is the first to show a high prevalence of Bd in Caatinga’s species and includes two new records of species infected by Bd: Rhinella granulosa and R. jimi. In addition, we discuss the possibility of amphibian with terrestrial habits serving as potential Bd reservoirs in semiarid climate regions12CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP155556/2018–52015/11821–0; 2016/ 25358–3The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Financial support was provided by grants from Coordenacão de Aperfeiçoamento de Pessoal de N ıvel Superior, Conselho Nacional de Desenvolvimento Cient ıfico e Tecnologico (#155556/2018–5), and Fundacão de Amparo a` Pesquisa do Estado de S~ao Paulo (#2015/11821–0; #2016/ 25358–3

Response to comment on 'Amphibian fungal panzootic causes catastrophic and ongoing loss of biodiversity'

Lambert et al. question our retrospective and holistic epidemiological assessment of the role of chytridiomycosis in amphibian declines. Their alternative assessment is narrow and provides an incomplete evaluation of evidence. Adopting this approach limits understanding of infectious disease impacts and hampers conservation efforts. We reaffirm that our study provides unambiguous evidence that chytridiomycosis has affected at least 501 amphibian species

Use of micro CHP plants to support the local operation of electric heat pumps

Fig. 1. Global distribution of chytridiomycosis-associated amphibian species declines. Bar plots indicate the number (N) of declined species, grouped by continental area and classified by decline severity. Brazilian species are plotted separately from all other South American species (South America W); Mesoamerica includes Central America, Mexico, and the Caribbean Islands; and Oceania includes Australia and New Zealand. No declines have been reported in Asia. n, total number of declines by region. [Photo credits (clockwise from top left): Anaxyrus boreas, C. Brown, U.S. Geological Survey; Atelopus varius, B.G.; Salamandra salamandra, D. Descouens, Wikimedia Commons; Telmatobius sanborni, I.D.l.R; Cycloramphus boraceiensis, L.F.T.; Cardioglossa melanogaster, M.H.; and Pseudophryne corroboree, C. Doughty

Historical distribution of Batrachochytrium dendrobatidis in Brazil

Orientador: Luís Felipe de Toledo Ramos PereiraDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: Os anfíbios são o grupo de vertebrados mais ameaçados em todo o mundo. As principais ameaças ao grupo são a perda de habitat e a quitridiomicose, uma doença infecciosa emergente causada pelo fungo Batrachochytrium dendrobatidis (Bd). O fungo se distribui por todos os continentes do mundo levando populações de anfíbios ao declínio ou extinção, e no Brasil sua distribuição é pouco compreendida. Muitos declínios foram registrados no sudeste do Brasil, principalmente nas décadas de 1970 e 1980, e as causas para esses declínios permanecem pouco esclarecidas. Em nosso trabalho analisamos aparatos bucais de mais de 30 mil girinos de todo o Brasil preservados em museus. Com isso, fomos capazes de identificar a distribuição do Bd em todo o território nacional e correlacionar positivamente o aumento da prevalência da quitridiomicose com os declínios registrados na Mata AtlânticaAbstract: Amphibians are the most threatened group of vertebrates in the world. The main threats to the group are habitat loss and chytridiomycosis, an emerging infectious disease caused by the fungus Batrachochytrium (Bd). The fungus is spread over all continents of the world leading amphibian populations to decline or extinction, and in Brazil its distribution is poorly understood. Many declines were recorded in southeastern Brazil, mainly in the 70's and 80's, and the causes for these declines remain unclear. In our work we analyze buccal apparatus of more than 30 thousand tadpoles from all over Brazil preserved in museums. Thus, we were able to identify the distribution of Bd throughout the country and positively correlate the increased prevalence of chytrid with the declines recorded in the Atlantic ForestMestradoEcologiaMestra em Ecologia2014/23388-7CAPESFAPES

Historical Amphibian Declines And Extinctions In Brazil Linked To Chytridiomycosis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The recent increase in emerging fungal diseases is causing unprecedented threats to biodiversity. The origin of spread of the frog-killing fungus Batrachochytrium dendrobatidis (Bd) is a matter of continued debate. To date, the historical amphibian declines in Brazil could not be attributed to chytridiomycosis; the high diversity of hosts coupled with the presence of several Bd lineages predating the reported declines raised the hypothesis that a hypervirulent Bd genotype spread from Brazil to other continents causing the recent global amphibian crisis. We tested for a spatio-temporal overlap between Bd and areas of historical amphibian population declines and extinctions in Brazil. A spatio-temporal convergence between Bd and declines would support the hypothesis that Brazilian amphibians were not adapted to Bd prior to the reported declines, thus weakening the hypothesis that Brazil was the global origin of Bd emergence. Alternatively, a lack of spatio-temporal association between Bd and frog declines would indicate an evolution of host resistance in Brazilian frogs predating Bd's global emergence, further supporting Brazil as the potential origin of the Bd panzootic. Here, we Bd-screened over 30 000 museum-preserved tadpoles collected in Brazil between 1930 and 2015 and overlaid spatio-temporal Bd data with areas of historical amphibian declines. We detected an increase in the proportion of Bd-infected tadpoles during the peak of amphibian declines (1979-1987). We also found that clusters of Bd-positive samples spatiotemporally overlapped with most records of amphibian declines in Brazil's Atlantic Forest. Our findings indicate that Brazil is post epizootic for chytridiomycosis and provide another piece to the puzzle to explain the origin of Bd globally.2841848Fundo de Apoio ao Ensino, a Pesquisa e Extensao (FAEPEX) [1105/13]Sao Paulo Research Foundation (FAPESP) [2014/23388-7]Coordination for the Improvement of Higher Education Personnel (PROEX-CAPES)National Council for Scientific and Technological Development (CNPq) [302589/2013-9, 405285/2013-2, 312895/2014-3]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Data from: Historical amphibian declines and extinctions in Brazil linked to chytridiomycosis

The recent increase in emerging fungal diseases is causing unprecedented threats to biodiversity. The origin of spread of the frog-killing fungus Batrachochytrium dendrobatidis (Bd) is a matter of continued debate. To date, the historical amphibian declines in Brazil could not be attributed to chytridiomycosis; the high diversity of hosts coupled with the presence of several Bd lineages predating the reported declines raised the hypothesis that a hypervirulent Bd genotype spread from Brazil to other continents causing the recent global amphibian crisis. We tested for a spatio-temporal overlap between Bd and areas of historical amphibian population declines and extinctions in Brazil. A spatio-temporal convergence between Bd and declines would support the hypothesis that Brazilian amphibians were not adapted to Bd prior to the reported declines, thus weakening the hypothesis that Brazil was the global origin of Bd emergence. Alternatively, a lack of spatio-temporal association between Bd and frog declines would indicate an evolution of host resistance in Brazilian frogs predating Bd's global emergence, further supporting Brazil as the potential origin of the Bd panzootic. Here, we Bd-screened over 30 000 museum-preserved tadpoles collected in Brazil between 1930 and 2015 and overlaid spatio-temporal Bd data with areas of historical amphibian declines. We detected an increase in the proportion of Bd-infected tadpoles during the peak of amphibian declines (1979–1987). We also found that clusters of Bd-positive samples spatio-temporally overlapped with most records of amphibian declines in Brazil's Atlantic Forest. Our findings indicate that Brazil is post epizootic for chytridiomycosis and provide another piece to the puzzle to explain the origin of Bd globally

Full database on Brazilian tadpoles

Presence of Bd infection in tadpoles from Brazi

Thermal mismatch explains fungal disease dynamics in Brazilian frogs

Theory predicts that susceptibility to disease in ectothermic hosts increases as temperatures depart from host’s thermal optima, because pathogens have functionally broader thermal tolerance ranges and acclimate faster than hosts to shifts in temperature. Hence, hosts adapted to cooler and warmer climates should be at greater risk of infection under abnormally warm and cool conditions, respectively. Batrachochytrium dendrobatidis (Bd) is a chytrid fungus that affects amphibians worldwide. In Brazil's Atlantic Forest, Bd outbreaks have been linked to numerous declines in amphibian populations, particularly in cooler high elevation areas. Thus, we hypothesize that years with abnormally warm temperatures could shift the balance in favor of the pathogen, thereby driving the historical declines. We also hypothesize that warm-adapted amphibians from lowland sites could experience elevated Bd infection risk during abnormally cold years. To test whether thermal mismatch (elevation vs. temperature anomaly) drove shifts in Bd prevalence through time we compiled a comprehensive database spanning 50 years, gathered across an elevational gradient within the Atlantic Forest. In agreement with our predictions, cool-adapted hosts had higher Bd prevalence when temperatures were higher than historical averages. In parallel, Bd prevalence in warm-adapted hosts was higher in colder-than-average years, although frogs from higher elevations exhibited an overall higher risk of disease due to disproportionally high infection prevalence. Our study links the thermal mismatch hypothesis with historical shifts in Bd prevalence in Brazilian frogs, indicating that Bd infections, modulated by climate change, may continue to have a negative impact on Neotropical amphibians

Suplemental material from Historical amphibian declines and extinctions in Brazil linked to chytridiomycosis

List of collections; Tables S1-S6; Figures S1-S

Amphibian Hymenochirus boettgeri as an experimental model for infection studies with the chytrid fungus Batrachochytrium dendrobatidis

ABSTRACTModel organisms are crucial in research as they can provide key insights applicable to other species. This study proposes the use of the amphibian species Hymenochirus boettgeri, widely available through the aquarium trade, as a model organism for the study of chytridiomycosis, a disease caused by the fungus Batrachochytrium dendrobatidis (Bd) and linked to amphibian decline and extinction globally. Currently, no model organisms are used in the study of chytridiomycosis, particularly because of the lack of availability and nonstandardized methods. Thus, laboratories around the world use wild local species to conduct Bd infection experiments, which prevents comparisons between studies and reduces reproducibility. Here, we performed a series of Bd infection assays that showed that H. boettgeri has a dose- and genotype-dependent response, can generalize previous findings on virulence estimates in other species, and can generate reproducible results in replicated experimental conditions. We also provided valuable information regarding H. boettgeri husbandry, including care, housing, reproduction, and heat treatment to eliminate previous Bd infections. Together, our results indicate that H. boettgeri is a powerful and low-ecological-impact system for studying Bd pathogenicity and virulence