Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
???displayArticle.abstract???
Amphibian species are experiencing population declines due to infection by the fungal pathogen, Batrachochytrium dendrobatidis (Bd). The African clawed frog (Xenopus laevis), an asymptomatic carrier of Bd, has been implicated in the spread of this pathogen through global trade and established invasive populations on several continents. However, research has not explored the relationships of both life stages of this amphibian with Bd. While the post-metamorphic individuals may act as a reservoir, spreading the infection to susceptible species, the filter-feeding larvae may consume the motile Bd zoospores from the water column, potentially reducing pathogen abundance and thus the likelihood of infection. We explore these contrasting processes by assessing Bd prevalence and infection intensities in field populations of post-metamorphic individuals, and performing laboratory experiments to determine if larval X. laevis preyed upon Bd zoospores. The water flea, Daphnia magna, was included in the Bd consumption trials to compare consumption rates and to explore whether intraguild predation between the larval X. laevis and Daphnia may occur, potentially interfering with control of Bd zoospores by Daphnia. Field surveys of three X. laevis populations in southern California, in which 70 post-metamorphic individuals were tested for Bd, found 10% infection prevalence. All infected individuals had very low infection loads (all Bd loads were below 5 zoospore equivalents). Laboratory experiments found that larval X. laevis consume Bd zoospores and therefore may reduce Bd abundance and transmission between amphibians. However, metamorphic and juvenile X. laevis exhibited intraguild predation by consuming Daphnia, which also prey upon Bd zoospores. The results suggest that X laevis is not a large reservoir for Bd and its larval stage may offer some reduction of Bd transmission through direct predation.
???displayArticle.pubmedLink???
29444096
???displayArticle.pmcLink???PMC5812569 ???displayArticle.link???PLoS One ???displayArticle.grants???[+]
Fig 1. Bd zoospore consumption by X. laevis and Daphnia.Average number of Bd zoospores found in the guts of X. laevis or on/in the entire three Daphnia after 4.5 hours of exposure to 442,000 zoospores. The zoospore values were log transformed to normalize the range of Bd zoospore values. All treatment groups were significantly different from each other (Permutation ANOVA: DF = 3, iterations = 5,000, p = <0.01; FDR p-value adjustments, p<0.05).
Fig 2. Bd zoospore consumption by X. laevis developmental stage.Number of zoospores consumed by X. laevis larvae of varying Gosner developmental stages [32] in the 4.5-hour trials.
Adams,
DNA Extraction Method Affects the Detection of a Fungal Pathogen in Formalin-Fixed Specimens Using qPCR.
2015, Pubmed
Adams,
DNA Extraction Method Affects the Detection of a Fungal Pathogen in Formalin-Fixed Specimens Using qPCR.
2015,
Pubmed
Boyle,
Rapid quantitative detection of chytridiomycosis (Batrachochytrium dendrobatidis) in amphibian samples using real-time Taqman PCR assay.
2004,
Pubmed
Briggs,
Enzootic and epizootic dynamics of the chytrid fungal pathogen of amphibians.
2010,
Pubmed
Direnzo,
Fungal infection intensity and zoospore output of Atelopus zeteki, a potential acute chytrid supershedder.
2014,
Pubmed
Garner,
The emerging amphibian pathogen Batrachochytrium dendrobatidis globally infects introduced populations of the North American bullfrog, Rana catesbeiana.
2006,
Pubmed
Goka,
Amphibian chytridiomycosis in Japan: distribution, haplotypes and possible route of entry into Japan.
2009,
Pubmed
Hite,
Joint effects of habitat, zooplankton, host stage structure and diversity on amphibian chytrid.
2016,
Pubmed
Hyatt,
Diagnostic assays and sampling protocols for the detection of Batrachochytrium dendrobatidis.
2007,
Pubmed
Mandl,
Reservoir host immune responses to emerging zoonotic viruses.
2015,
Pubmed
McMahon,
Chytrid fungus Batrachochytrium dendrobatidis has nonamphibian hosts and releases chemicals that cause pathology in the absence of infection.
2013,
Pubmed
Ramsey,
Immune defenses against Batrachochytrium dendrobatidis, a fungus linked to global amphibian declines, in the South African clawed frog, Xenopus laevis.
2010,
Pubmed
,
Xenbase
Reeder,
A reservoir species for the emerging Amphibian pathogen Batrachochytrium dendrobatidis thrives in a landscape decimated by disease.
2012,
Pubmed
Schmeller,
Microscopic aquatic predators strongly affect infection dynamics of a globally emerged pathogen.
2014,
Pubmed
Searle,
Daphnia predation on the amphibian chytrid fungus and its impacts on disease risk in tadpoles.
2013,
Pubmed
Stuart,
Status and trends of amphibian declines and extinctions worldwide.
2004,
Pubmed
Tinsley,
Chytrid fungus infections in laboratory and introduced Xenopus laevis populations: assessing the risks for U.K. native amphibians.
2015,
Pubmed
,
Xenbase
Venesky,
Linking manipulative experiments to field data to test the dilution effect.
2014,
Pubmed
Voyles,
Interactions between Batrachochytrium dendrobatidis and its amphibian hosts: a review of pathogenesis and immunity.
2011,
Pubmed
Vredenburg,
Prevalence of Batrachochytrium dendrobatidis in Xenopus collected in Africa (1871-2000) and in California (2001-2010).
2013,
Pubmed
,
Xenbase
Vredenburg,
Dynamics of an emerging disease drive large-scale amphibian population extinctions.
2010,
Pubmed
Weldon,
Origin of the amphibian chytrid fungus.
2004,
Pubmed
,
Xenbase
Yang,
First detection of the amphibian chytrid fungus Batrachochytrium dendrobatidis in free-ranging populations of amphibians on mainland Asia: survey in South Korea.
2009,
Pubmed
