Changes in the skin microbiome composition of anurans infected with Batrachochytrium dendrobatidis (Chytridiomycota) and ranavirus (Iridoviridae)

• Grant number: 18/05217-1
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: July 09, 2018
• End date: January 08, 2019
• Field of knowledge: Biological Sciences - Ecology
• Principal Investigator: Luis Felipe de Toledo Ramos Pereira
• Grantee: Joice Ruggeri Gomes
• Supervisor: Trenton William John Garner
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: Zoological Society of London (ZSL), England
• Associated to the scholarship: 17/01917-6 - Interaction between the chytrid Batrachochytrium dendrobatidis and the Ranavirus in anuran assemblages from the Southern Atlantic forest, BP.PD

Abstract

Emerging infectious diseases are considered a major threat to the global biodiversity. In general, pathogens emerge in populations either because they are novel or due to a decrease in host immune system. Ranavirus (Rv) and Batrachochytrium dendrobatidis (Bd) are two emergent infectious pathogens responsible for declines of amphibian populations worldwide. Both Bd and Rv are spread via water and via direct contact with a sick individual, making dispersion extremely effective. Batrachochytrium dendrobatidis causes chytridiomycosis in less tolerant animals and might cause osmoregulation disturbance, whereas Rv might cause tissue death in multiple organs. Thus, the two microorganisms disrupt the skin of infected animals leading to a change in host microbial communities. Because skin associated microbiomes are so important for protecting the host from infections, this change of bacterial community might also lead the animal to death. Although there are many studies on the dynamics of Bd and Rv and the effect of infection on amphibian populations, usually the focus lies in one pathogen or the other. Therefore, the consequences of coinfection by both microorganisms are poorly known. In Brazil, for example, studies on amphibian diseases are almost exclusively on Bd and the knowledge on Rv is limited to a few bullfrog farms, and the interaction between the two pathogens was never explored. In this study we will investigate the skin microbiome of amphibians infected with Bd, infected with Rv, and coinfected with both. We expect a shift in the bacterial community and increase of susceptibility to secondary infections. Consequences of coinfection will be discussed to help mitigating amphibian conservation action plans in the Brazilian Atlantic Forest, as proposed in the main project, especially because it is an important hotspot for biodiversity and, yet, one of the most threatened biome in the world. (AU)