28th ANNUAL EASTERN FISH HEALTH WORKSHOP April 21-25, 2003 Distribution Of Chytridiomycosis (Batrachochytrium Dendrobatidis) Within Amphibian Populations Of The Ecuadorian Andes Rachel E. Kosoff1, Luis A. Coloma2, Paul R. Bowser1 1Aquatic Animal Health Program, Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University,  Ithaca, New York  14853-6401; 2Museo de Zoologia, Pontificia Universidad  Catolica del Ecuador, Apartado 17-01-2184, Quito-Ecuador Amphibians from North America, South America, Europe, Asia, Africa and Australia have been diagnosed with Chytridiomycosis (Batrachochytrium dendrobatidis infection) in recent years.  Fourteen families, and 93 species of amphibians have been infected worldwide.  Within the United States, the fungus occurs in California, Arizona, Colorado, North Dakota, and Wyoming.  In this study, the distribution of Chytridiomycosis throughout the Andes of Ecuador, South America was investigated in response to recent reports of species diversity in Ecuador that have declined in 26 of the 415 amphibian species, without evidence of habitat destruction.  Specimens evaluated included those archived at the Museum of Zoology at the Universidad Catolica del Ecuador and recent collections.  Presence of the disease was determined in Gastrotheca plumbea, G. pseustes, G. riobambae, and G. psycrophila by examination of skin from the pelvic patch of juvenile frogs captured as tadpoles, as well as on tadpole mouthparts.  Skin was stained using haemotoxylin and eosin techniques.  Clinical signs included lethargy, abnormal posture, loss of reflex and death.  Infection caused diffuse dermatitis characterized by epidermal hyperplasia, hyperkeratosis and variable degrees of cutaneous ulceration, hyperemia and colonization of the keratinized layers of the epidermis by sporangia of the chytrid.  Transmission occurs by release of zoospores into the water from sporangia.  Random sampling of tadpoles was done throughout the Andes between the border of Columbia and Peru, at elevations between 2250 meters and 4150 meters above sea level.  Many sites sampled were the same locations as for the archival samples.  Locations providing infected archival specimens also provided infected specimens in this more current investigation.  Distances among positive sites were evaluated to theorize about the recent spread of the pathogen.  Data was also collected to compare presence of the disease with certain environmental parameters. Return to 28th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page