Chytridiomycosis outbreak in a Chilean giant frog (Calyptocephalella gayi) captive breeding program: genomic characterization and pathological findings
Author(s)
Type
Journal Article
Abstract
Emerging infectious diseases in wildlife are increasingly associated with animal mortality and species declines, but their source and genetic characterization often remains elusive. Amphibian chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), has been associated with catastrophic and well-documented amphibian population declines and extinctions at the global scale. We used histology and whole-genome sequencing to describe the lesions caused by, and the genetic variability of, two Bd isolates obtained from a mass mortality event in a captive population of the threatened Chilean giant frog (Calyptocephalella gayi). This was the first time an association between Bd and high mortality had been detected in this charismatic and declining frog species. Pathological examinations revealed that 30 dead metamorphosed frogs presented agnathia or brachygnathia, a condition that is reported for the first time in association with chytridiomycosis. Phylogenomic analyses revealed that Bd isolates (PA1 and PA2) from captive C. gayi group with other Bd isolates (AVS2, AVS4, and AVS7) forming a single highly supported Chilean Bd clade within the global panzootic lineage of Bd (BdGPL). These findings are important to inform the strengthening of biosecurity measures to prevent the impacts of chytridiomycosis in captive breeding programs elsewhere.
Date Issued
2021-09-24
Date Acceptance
2021-08-27
Citation
Frontiers in Veterinary Science, 2021, 8
ISSN
2297-1769
Publisher
Frontiers Media
Journal / Book Title
Frontiers in Veterinary Science
Volume
8
Copyright Statement
© 2021 Alvarado-Rybak, Acuña, Peñafiel-Ricaurte, Sewell, O'Hanlon, Fisher, Valenzuela-Sánchez, Cunningham and Azat. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
License URL
Sponsor
Medical Research Council (MRC)
Natural Environment Research Council (NERC)
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/34631859
Grant Number
MR/R015600/1
NE/S000844/1
Subjects
Batrachochytrium dendrobatidis
BdGPL
Chile
agnathia
amphibians
brachygnathia
emerging infectious disease
whole-genome sequencing
Publication Status
Published
Coverage Spatial
Switzerland
Article Number
ARTN 733357