Following White-nose Syndrome development and Pd-infection status in cave-dwelling Tricolored bats by e-nose volatile emissions analysis

Abstract

Early detection of White-nose Syndrome (WNS) of bats within winter hibernacula is essential for applying effective and timely disease-control measures. Recent evidence suggests that analysis of volatile organic compound (VOC) emissions from bats over time using electronic-nose (e-nose) devices has potential for monitoring Pd-infection status and WNS disease progress in individual cave bats following cave entry. An e-nose investigation of whole-body VOC emissions from Tricolored bats (Perimyotis subflavus), sampled noninvasively (without bat contact or handling) within 13 caves and 2 mines in Arkansas, showed that the majority of tricolored bats are relatively disease free when first entering caves, but acquire Pd-infections over time, often leading to WNS disease development at variable rates prior to the exiting of surviving bats from caves in the Spring. Healthy bats exhibited significantly different E-nose smellprint signatures than Pd-infected bats, both prior to and following disease and associated WNS symptom development. These differences in VOC emissions were indicative of Pd-induced pathophysiological changes in bat metabolic pathways associated with pathogenesis as it progressed from healthy to early and late WNS disease states. Further evidence from 3-dimensional Discriminant Factor Analysis (DFA) showed distinct clustering of bat data from individuals with different VOC profiles, indicative of differences in Pd-infection status and WNS symptom development. These data were confirmed by differences in VOC GC-retention times, peak numbers, peak areas, and VOC chemical identities, indicated in chromatograms from dual-column GC-analyses. We identified several (low molecular weight) quantitative VOC metabolic biomarkers as potential early indicators of Pd-infections, well prior to WNS symptom development. Healthy-bat quantitative VOC biomarkers significantly decreased in concentration or were completely absent within bat emissions as WNS disease progressed. The e-nose approach provides a new noninvasive tool for monitoring changes in bat physiological processes that occur during transitions from healthy to diseased states during winter hibernation periods.

Citation

Doty, Anna C.; Wilson, Alphus Dan; Forse, Lisa B.; Risch, Thomas, S. 2024. Following White-nose Syndrome development and Pd-infection status in cave-dwelling Tricolored bats by e-nose volatile emissions analysis. (Abstract) 2024 White-nose Syndrome Virtual Meeting Annual Conference, online Webinar, 11-13 June 2024.