Low resistance to chytridiomycosis in direct-developing amphibians

Author(s)

Mesquita, Andrea F. C. ^{[1, 2]} ; Lambertini, Carolina ^[3] ; Lyra, Mariana ^{[1, 2]} ; Malagoli, Leo R. ^{[1, 2]} ; James, Timothy Y. ^[4] ; Toledo, Luis Felipe ^[3] ; Haddad, Celio F. B. ^{[1, 2]} ; Becker, C. Guilherme ^[5]

Affiliation

^[1] Univ Estadual Paulista UNESP, Inst Biociencias, Dept Zool, BR-13506900 Rio Claro, SP - Brazil

^[2] Ctr Aquicultura CAUNESP, BR-13506900 Rio Claro, SP - Brazil

^[3] Univ Estadual Campinas, Dept Biol Anim, IB, BR-13083862 Campinas, SP - Brazil

^[4] Univ Michigan, Dept Ecol & Evolutionary Biol, Ann Arbor, MI 48109 - USA

^[5] Univ Alabama, Dept Biol Sci, Tuscaloosa, AL 35487 - USA

• Document type: Journal article
• Source: SCIENTIFIC REPORTS; v. 7, NOV 30 2017.
• Web of Science Citations: 9

Abstract

Host-generalist pathogens sporadically infect naive hosts, potentially triggering epizootics. The waterborne fungus Batrachochytrium dendrobatidis (Bd) is linked to declines of hundreds of amphibian species with aquatic larvae. Although several population declines and extinctions attributed to Bd have been reported among cryptic species undergoing direct development away from water, epidemiological studies focused on these terrestrial frogs are lacking. Our field data support that terrestrial direct-developing hosts are less exposed to Bd during their ontogeny than species with aquatic larvae, and thus they might lack adaptive responses against waterborne chytrids. Using controlled laboratory experiments, we exposed wild-caught amphibian species with terrestrial and aquatic life histories to Bd and found that direct developers showed more rapid increases in infection loads and experienced higher mortality rates than species with aquatic larvae. Our findings provide novel information about host responses to generalist pathogens and specifically show that our focal direct developing species have low resistance to Bd infections. Finally, our results underscore that we should not ignore Bd as a potential threat to direct developing species simply because they are less exposed to Bd in nature; instead future amphibian conservation plans should include efforts to safeguard hundreds of direct-developing amphibian species globally. (AU)

• FAPESP's process: 14/23388-7 - Comunication and sensory systems of the anurans of the Atlantic Forest
• Grantee: Luis Felipe de Toledo Ramos Pereira
• Support Opportunities: Regular Research Grants
• FAPESP's process: 16/25358-3 - The chytrid fungus: from its origins to its consequences
• Grantee: Luis Felipe de Toledo Ramos Pereira
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/50741-7 - Diversity and conservation of Brazilian amphibians
• Grantee: Célio Fernando Baptista Haddad
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 14/23677-9 - New approaches to ecology and conservation: phylogenetic and functional diversity of amphibians and snakes of Brazilian Atlantic Forest
• Grantee: Ricardo Jannini Sawaya
• Support Opportunities: Regular Research Grants