This journal club is about an article entitled : “Presence of the Amphibian Chytrid fungus Batrachochytrium dendrobatidis in Native Amphibians Exported from Madagascar” by Kolby JE that just got published today (March 5th 2014) in the Open access journal PlosOne. You can access (free of charge) the article discussed by following the link below:
Citation: Kolby JE (2014) Presence of the Amphibian Chytrid Fungus Batrachochytrium dendrobatidis in Native Amphibians Exported from Madagascar. PLoS ONE 9(3): e89660. doi:10.1371/journal.pone.0089660
In this research, the author has screened 565 native amphibians from Madagascar for the presence of the chytrid fungus Batrachochytrium dendribatidis using qPCR methods. The fungus was detected in three amphibians from three different species Heterixalus alboguttatus, Heterixalus betsileo, and Scaphiophryne spinosa. Although the animals screened for this research were exported from Madagascar, the condition of shipment and the immediate screening of the amphibians following their arrival in the United states strongly suggest that the fungus is now present in Madagascar. None of the three animals showed symptoms associated with the disease but this raises a major concern for the conservation of Madagascar’s amphibians.
Madagascar’s Amphibian fauna is extremely rich and unique with more than 99% of the species being endemic. Currently 288 species are described and more than another hundred remain to be named. This constitutes more than 3.7% of the world’s amphibian fauna (Glaw and Vences in Goodman, 2003; ACSAM, 2006). And despite numerous attempts, the fungus Batrachochytrium dendribatidis (Bd) has not been detected in Malagasy frogs (e.g Weldon et al 2008, Crottini et al., 2011, Andreone 2008). In fact, Madagascar was one of the last remaining countries were Bd was not detected.
Batrachochytrium dendribatidis is THE major cause of amphibian decline worldwide it affects more than 50% of species. It has originated in Africa and has spread worldwide via the use of the African clawed frog (Xenopus) as a pregnancy test for women in the 1920’s. Some of the frogs that were shipped between continents harbored the deadly fungus and spread it to naive endemic species of amphibians causing the global decline of amphibians that were are experiencing today (Berger et al., 1998; Skerratt et al., 2007; Fisher et al., 2009). In fact, infection with Bd has been called “the worst infectious disease ever recorded among vertebrates in terms of the number of species impacted, and it’s propensity to drive them to extinction” (Gascon et al, 2007).
The frogs tested in this article were legally exported from Madagascar and destined for the pet trade in the United States. The animals were collected in the wild and shipped directly to America, which strongly suggest the presence of the fungus in the natural habitat of some amphibians (and particularly H. betsileo).
The author of this article (J. Kolby) calls for urgent action to determine the current extent and distribution of the infection in Malagasy amphibians.