DAO 61:85-88 (2004)  -  doi:10.3354/dao061085

Co-localisation of Batrachochytrium dendrobatidis and keratin for enhanced diagnosis of chytridiomycosis in frogs

Veronica Olsen1, Alex D. Hyatt1,*, Donna G. Boyle1, Diana Mendez2

1CSIRO, Division of Livestock Industries, Australian Animal Health Laboratory, 5 Portarlington Road, East Geelong, Victoria 3220, Australia
2Amphibian Diseases Group, School of Public Health and Tropical Medicine, James Cook University, Townsville, Queensland 4811, Australia
*Corresponding author. Email:

ABSTRACT: Chytridiomycosis is a disease of post-metamorphic frogs caused by the fungus Batrachochytrium dendrobatidis and is associated with large declines in frog populations on a global scale. B. dendrobatidis is found only in the keratinised tissues, which include the mouthparts of healthy tadpoles. The epidermis of infected post-metamorphic frogs is thickened (hyperkeratosis) and the superficial layer can sometimes slough. Diagnosis is most commonly performed on stained sections of toe clips or ventral skin. Accurate interpretation can be difficult and requires a high level of expertise, particularly in infected animals exhibiting hyperkeratosis with sloughing. Misdiagnosis can occur when zoosporangia of B. dendrobatidis are shed with the superficial keratin layers. We have developed a staining protocol based on previously described methods to detect both B. dendrobatidis and keratin, to improve the sensitivity and specificity of diagnosis of chytridiomycosis by inexperienced diagnosticians.


KEY WORDS: Batrachochytrium dendrobatidis · Chytridiomycosis · Alkaline phosphatase · HollandeĀ¹s Trichrome · Diagnostic assay


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