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Abstract The amphibian chytrid fungusBatrachochytrium dendrobatidis(Bd) is a cosmopolitan pathogen with numerous distinct lineages. The global panzootic lineage (Bd-GPL) is the most widespread and virulent lineage and is responsible for many recorded amphibian declines. Mapping the extent ofBd-GPL and other more established lineages is important for predicting disease dynamics in amphibian communities. Ecuador is the most biodiverse country per unit area for amphibian taxa and, thus, a priority for studies on genotypic diversity ofBd. In this study, we tested skin swab samples collected from 464 individual amphibians across coastal, Andean montane, and Amazonian forests, for the presence of twoBdlineages known to be present in South America: the globally-distributedBd-GPL and the Brazilian-endemicBd-Asia2/Brazil lineage. By using a discriminatory qPCR SNP assay, we found widespread prevalence ofBd-GPL in Ecuador in diverse host taxa. Genotyping efficiency was 36% in this study, meaning that one in every three swabs that tested positive forBdin infection assays were successfully genotyped. Through this study, we provide further support for the presence of a singleBdlineage in this neotropical biodiversity hotspot.
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Assessment of Batrachochytrium dendrobatidis and ranavirus among wild amphibians from four Philippine islands
The most comprehensive study on amphibian chytridiomycosis in southeast Asia to date was conducted by Swei et al. (2011), who screened over 3,000 individuals and found only 2.35% were positive for Bd. Those individuals observed to be Bd-positive were sampled from Indonesia (0.25% infection rate), Laos (0.73%), Malaysia (0.90%), and the Philippines (8.01%). Although Philippine samples showed a higher infection rate in the study, the infected individuals came from a single, highly disturbed mountain on Luzon Island (Swei et al. 2011). Given the unique biogeographic history of the Philippine archipelago, and its importance to global amphibian diversity as a megadiverse nation and biodiversity hotspot (Myers et al. 2000), additional studies are needed across a broader region of the country to better evaluate the prevalence of infectious amphibian diseases. Here, we present novel data on the presence and distribution of both Bd and RV pathogens among wild amphibian populations on the islands of Calayan, Camiguin Norte, Luzon, and Negros in the central and northern Philippines.
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- PAR ID:
- 10161900
- Date Published:
- Journal Name:
- Herpetological review
- Volume:
- 50
- Issue:
- 4
- ISSN:
- 0018-084X
- Page Range / eLocation ID:
- 729-734
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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