Preliminary Evidence Suggests the Transcriptomic Response of Tricolored Bats to White‐Nose Syndrome Is Similar but Not Identical to That of Little Brown Bats

ABSTRACT Understanding the pathophysiology of emerging wildlife diseases can inform treatment, improve the projections of long‐term population trajectories, and reveal variation in population‐level impacts among species. Research on white‐nose syndrome (WNS) in hibernating North American bats has largely focused on a single highly susceptible species, the little brown bat ( Myotis lucifugus ). Another susceptible species, the tricolored bat ( Perimyotis subflavus ), has experienced population declines comparable to or greater than those of little brown bats but remains understudied. In particular, the immune response of tricolored bats to WNS has not previously been evaluated. Here, we conduct a preliminary analysis comparing part of the transcriptomic response of tricolored bats to WNS with the little brown bat response. We analyzed 14 tricolored and 13 little brown bat samples collected from Colossal Cave, Kentucky, USA in 2017, where WNS has been present since 2013. We also included 26 little brown bat samples collected from a nearby hibernation site in 1999, prior to WNS emergence. Lacking a proper pre‐WNS control for tricolored bats, we conducted pairwise differential expression analyses between the three sample groups and evaluated the overlap between results to infer part of the tricolored bat response to WNS. These initial results suggested that tricolored bats exhibited differential expression patterns characteristic of susceptible species, including large changes in gene expression still apparent at the end of the hibernation season. Differentially expressed genes were associated with immune, metabolic, and circadian functions, broadly resembling the response observed in little brown bats. However, there was variation in the specific genes involved between the two species. Overall, tricolored bats appear to mount a pronounced immune response to WNS that is similar, but not identical, to that of little brown bats.