Unprecedented global climate change and increasing rates of infectious disease emergence are occurring simultaneously. Infection with emerging pathogens may alter the thermal thresholds of hosts. However, the effects of fungal infection on host thermal limits have not been examined.
View Article and Find Full Text PDFWildlife diseases pose an increasing threat to biodiversity and are a major management challenge. A striking example of this threat is the emergence of chytridiomycosis. Despite diagnosis of chytridiomycosis as an important driver of global amphibian declines 15 years ago, researchers have yet to devise effective large-scale management responses other than biosecurity measures to mitigate disease spread and the establishment of disease-free captive assurance colonies prior to or during disease outbreaks.
View Article and Find Full Text PDFSince the early 1980s, the southern corroboree frog Pseudophryne corroboree and northern corroboree frog P. pengilleyi have been in a state of decline from their sub-alpine and high montane bog environments on the southern tablelands of New South Wales, Australia. To date, there has been no adequate explanation as to what is causing the decline of these species.
View Article and Find Full Text PDFEffective and safe treatments of chytridiomycosis in amphibians, caused by Batrachochytrium dendrobatidis, are needed to help prevent mortality in captive programs for threatened species, to reduce the risk of spread, and to better manage the disease in threatened populations. We describe a simple method to determine minimum inhibitory concentrations (MICs) of antifungal agents that involves adding zoospores to various drug concentrations in 96 well plates and microscopic observation after four days. We report results from testing 10 commercially available antifungal compounds: benzalkonium chloride (<0.
View Article and Find Full Text PDFAlthough mortality in 3 groups of 15 green tree frogs Litoria caerulea exposed to 3 isolates of Batrachochytrium dendrobatidis was 100%, time to death varied with isolate, highlighting the importance of strain and/or passage history in pathogenicity studies and possibly in the epidemiology of chytridiomycosis. A standard naming scheme for isolates of B. dendrobatidis is proposed.
View Article and Find Full Text PDFThe emerging infectious disease chytridiomycosis is thought to have contributed to many of the recent alarming declines in amphibian populations. Mortalities associated with these declines have often occurred during cooler seasons and at high elevations, suggesting that environmental temperature may be an important factor in disease emergence. We found that thermal environment affects the progress of the disease, and that housing frogs Litoria chloris at an environmental temperature of 37 degrees C for less than 16 h can clear them of the chytrid pathogen Batrachochytrium dendrobatidis.
View Article and Find Full Text PDFPolyclonal antibodies were produced for diagnosing chytridiomycosis in amphibians. Two sheep and 4 rabbits were inoculated with homogenized whole culture of Batrachochytrium dendrobatidis in Freund's complete adjuvant or triple adjuvant. Antisera from all animals reacted strongly with all stages of B.
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