Batrachochytrium salamandrivorans Can Devour More than Salamanders.

Area of Science:

• Amphibian pathology
• Infectious diseases
• Conservation biology

Background:

• Batrachochytrium salamandrivorans (B. salamandrivorans) is a fungus causing significant salamander declines in Europe.
• The role of invasive species, particularly those in international trade, as potential carriers of B. salamandrivorans is not well understood.

Purpose of the Study:

• To investigate if the invasive Cuban treefrog (Osteopilus septentrionalis) can act as an asymptomatic carrier of B. salamandrivorans.
• To determine if Cuban treefrogs can develop chytridiomycosis when exposed to B. salamandrivorans zoospore doses known to infect salamanders.

Main Methods:

• Cuban treefrogs were exposed to varying doses of B. salamandrivorans zoospores.
• Infected frogs were used to isolate B. salamandrivorans, fulfilling Koch's postulates.
• Eastern newts (Notophthalmus viridescens) were exposed to the isolated B. salamandrivorans to confirm pathogenicity.

Main Results:

• Cuban treefrogs were successfully infected with B. salamandrivorans.
• Chytridiomycosis developed in Cuban treefrogs at the two highest zoospore exposure doses.
• The pathogenicity of the isolated B. salamandrivorans was confirmed in eastern newts via histopathology.

Conclusions:

• This study provides the first documentation of B. salamandrivorans chytridiomycosis in a frog species.
• Cuban treefrogs can be infected and develop disease, expanding the known host range and conservation threat of B. salamandrivorans.
• The international trade of invasive species like the Cuban treefrog poses a significant risk for the mobilization and spread of this amphibian pathogen.