Why do not die Japanese frogs with chytrid fungus.

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K06939
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Conservation of biological resources
• Research Institution: Azabu University
• Principal Investigator: UNE Yumi 麻布大学, 獣医学部, 教授 (40160303)
• Co-Investigator(Renkei-kenkyūsha): TOMODA Hiroshi 北里大学, 薬学部, 教授 (70164043)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: カエルツボカビ / 両生類 / 宿主 / 病原体 / 生態系保全 / 新興感染症

Outline of Final Research Achievements

Chytrid fungus is an important emerging pathogen of amphibians, but does not cause mortality in native species. In this study, we aimed to elucidate pathogenesis from the viewpoint of both frog (host) and Batrachochytrium dendrobatidis Bd (pathogen). It was found that the Bd haplotype based on difference in the ITS-1 region expressed different morphology, proliferative behavior, and pathogenicity. Additionally, several Bd haplotypes, mainly that of attenuated Bd, were naturally maintained in native species. In the infection experiment using the immunosuppressive model, finding of transient subclinical infection suggested that biological defense mechanisms other than immunity may be involved in Bd resistance of native species. Moreover, the observed change in electrolyte balance due to chytrid fungus was caused by abnormal water permeability of the skin.

Free Research Field

獣医病理学