Experimental Infection ofTadarida brasiliensiswithPseudogymnoascus destructans, the Fungus That Causes White-Nose Syndrome

ABSTRACTWhite-nose syndrome (WNS) is causing significant declines in populations of North American hibernating bats, and recent western and southern expansions of the disease have placed additional species at risk. Understanding differences in species susceptibility and identifying management actions to reduce mortality of bats from WNS are top research priorities. However, the use of wild-caught susceptible bats, such asMyotis lucifugus, as model species for WNS research is problematic and places additional pressure on remnant populations. We investigated the feasibility of usingTadarida brasiliensis, a highly abundant species of bat that tolerates captivity, as the basis for an experimental animal model for WNS. Using methods previously established to confirm the etiology of WNS inM. lucifugus, we experimentally infected 11T. brasiliensisbats withPseudogymnoascus destructansin the laboratory under conditions that induced hibernation. We detectedP. destructanson all 11 experimentally infected bats, 7 of which exhibited localized proliferation of hyphae within the epidermis, dermis, and subcutaneous tissue, similar to invasive cutaneous ascomycosis observed inM. lucifugusbats with WNS. However, the distribution of lesions across wing membranes ofT. brasiliensisbats was limited, and only one discrete “cupping erosion,” diagnostic for WNS, was identified. Thus, the rarity of lesions definitive for WNS suggests thatT. brasiliensisdoes not likely represent an appropriate model for studying the pathophysiology of this disease. Nonetheless, the results of this study prompt questions concerning the potential for free-ranging, migratoryT. brasiliensisbats to become infected withP. destructansand move the fungal pathogen between roost sites used by species susceptible to WNS.IMPORTANCEWhite-nose syndrome (WNS) is a fungal disease that is causing severe declines of bat populations in North America. Identifying ways to reduce the impacts of this disease is a priority but is inhibited by the lack of an experimental animal model that does not require the use of wild-caught bat species already impacted by WNS. We tested whetherTadarida brasiliensis, one of the most abundant species of bats in the Americas, could serve as a suitable animal model for WNS research. WhileT. brasiliensisbats were susceptible to experimental infection with the fungus under conditions that induced hibernation, the species exhibited limited pathology diagnostic for WNS. These results indicate thatT. brasiliensisis not likely a suitable experimental model for WNS research. However, the recovery of viable WNS-causing fungus from experimentally infected bats indicates a potential for this species to contribute to the spread of the pathogen where it coexists with other species of bats affected by WNS.