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Thomas H Kunz - One of the best experts on this subject based on the ideXlab platform.
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hibernating little brown Myotis Myotis lucifugus show variable immunological responses to white nose syndrome
PLOS ONE, 2013Co-Authors: Marianne S Moore, Jonathan D Reichard, Timothy D Murtha, Morgan L Nabhan, Rachel Pian, Jennifer S Ferreira, Thomas H KunzAbstract:White-nose syndrome (WNS) is an emerging infectious disease devastating hibernating North American bat populations that is caused by the psychrophilic fungus Geomyces destructans. Previous histopathological analysis demonstrated little evidence of inflammatory responses in infected bats, however few studies have compared other aspects of immune function between WNS-affected and unaffected bats. We collected bats from confirmed WNS-affected and unaffected sites during the winter of 2008–2009 and compared estimates of their circulating levels of total leukocytes, total immunoglobulins, cytokines and total antioxidants. Bats from affected and unaffected sites did not differ in their total circulating immunoglobulin levels, but significantly higher leukocyte counts were observed in bats from affected sites and particularly in affected bats with elevated body temperatures (above 20°C). Bats from WNS-affected sites exhibited significantly lower antioxidant activity and levels of interleukin-4 (IL-4), a cytokine that induces T cell differentiation. Within affected sites only, bats exhibiting visible fungal infections had significantly lower antioxidant activity and levels of IL-4 compared to bats without visible fungal infections. Overall, bats hibernating in WNS-affected sites showed immunological changes that may be evident of attempted defense against G. destructans. Observed changes, specifically elevated circulating leukocytes, may also be related to the documented changes in thermoregulatory behaviors of affected bats (i.e. increased frequencies in arousal from torpor). Alterations in immune function may reflect expensive energetic costs associated with these processes and intrinsic qualities of the immunocapability of hibernating bats to clear fungal infections. Additionally, lowered antioxidant activity indicates a possible imbalance in the pro- versus antioxidant system, may reflect oxidative tissue damage, and should be investigated as a contributor to WNS-associated morbidity and mortality.
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specific alterations in complement protein activity of little brown Myotis Myotis lucifugus hibernating in white nose syndrome affected sites
PLOS ONE, 2011Co-Authors: Marianne S Moore, Jonathan D Reichard, Timothy D Murtha, Bita Zahedi, Renee M Fallier, Thomas H KunzAbstract:White-nose syndrome (WNS) is the most devastating condition ever reported for hibernating bats, causing widespread mortality in the northeastern United States. The syndrome is characterized by cutaneous lesions caused by a recently identified psychrophilic and keratinophylic fungus (Geomyces destructans), depleted fat reserves, atypical behavior, and damage to wings; however, the proximate cause of mortality is still uncertain. To assess relative levels of immunocompetence in bats hibernating in WNS-affected sites compared with levels in unaffected bats, we describe blood plasma complement protein activity in hibernating little brown Myotis (Myotis lucifugus) based on microbicidal competence assays using Escherichia coli, Staphylococcus aureus and Candida albicans. Blood plasma from bats collected during mid-hibernation at WNS-affected sites had higher bactericidal ability against E. coli and S. aureus, but lower fungicidal ability against C. albicans when compared with blood plasma from bats collected at unaffected sites. Within affected sites during mid-hibernation, we observed no difference in microbicidal ability between bats displaying obvious fungal infections compared to those without. Bactericidal ability against E. coli decreased significantly as hibernation progressed in bats collected from an affected site. Bactericidal ability against E. coli and fungicidal ability against C. albicans were positively correlated with body mass index (BMI) during late hibernation. We also compared complement activity against the three microbes within individuals and found that the ability of blood plasma from hibernating M. lucifugus to lyse microbial cells differed as follows: E. coli>S. aureus>C. albicans. Overall, bats affected by WNS experience both relatively elevated and reduced innate immune responses depending on the microbe tested, although the cause of observed immunological changes remains unknown. Additionally, considerable trade-offs may exist between energy conservation and immunological responses. Relationships between immune activity and torpor, including associated energy expenditure, are likely critical components in the development of WNS.
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free ranging little brown Myotis Myotis lucifugus heal from wing damage associated with white nose syndrome
Ecohealth, 2011Co-Authors: Nathan W Fuller, Jonathan D Reichard, Morgan L Nabhan, Spenser R Fellows, Lesley Pepin, Thomas H KunzAbstract:White-nose syndrome (WNS) is having an unprecedented impact on hibernating bat populations in the eastern United States. While most studies have focused on widespread mortality observed at winter hibernacula, few have examined the consequences of wing damage that has been observed among those bats that survive hibernation. Given that WNS-related wing damage may lead to life-threatening changes in wing function, we tested the hypothesis that reduced abundance of free-ranging little brown Myotis (Myotis lucifugus) with severe wing damage as the summer progresses is due to healing of wing tissue. Photographs of captured and recaptured adult females were examined for wing damage and healing rates were calculated for each category of wing damage index (WDI = 0–3). We found that free-ranging bats with severe wing damage were able to heal to a lower WDI score within 2 weeks. Bats with the most severe wing damage had faster healing rates than did individuals with less damage. We also found a significant relationship between body condition and WDI for adult females captured in the early weeks of the active season. Our results support the hypothesis that some bats can heal from severe wing damage during the active season, and thus may not experience increased mortality associated with reduced functions of wings. We urge researchers and wildlife managers to use caution when interpreting data on WDI to assess the impact of WNS on bat populations, especially during the later months of the active season.
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Two Novel BatCams for Censusing Small Colonies of Bats
2010Co-Authors: Thomas H Kunz, Jonathan D Reichard, Johnny C. Chau, Laura Hong, Margrit Betke, Thomas D. C. LittleAbstract:We developed two infrared BatCams capable of censusing emerging bats—a remote controlled, panzoom-tilt camera, and a fixed focal-length lens camera. The remote-controlled BatCam consists of a small, weatherized Internet camera connected to a local video server and gateway for Internet access. The server enables video recording at predetermined intervals corresponding to expected nightly emergence. Internet connectivity allows sampling the real-time video from off-site. A second BatCam mounted inside a small, weatherized, transparent Pelican case recorded data directly to a laptop computer. Using both BatCam’s, we successfully censused a small bat colony of little brown Myotis (Myotis lucifugus) that emerged nightly through two small portals. Bats in each video frame were first detected using custom-designed computer vision algorithms using background modeling that first compared bats with an estimate of the background images. A second algorithm tracked each newly detected bat through the camera’s field of view. Advantages and disadvantages of each camera system are considered
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influence of climate and reproductive timing on demography of little brown Myotis Myotis lucifugus
Journal of Animal Ecology, 2010Co-Authors: Winifred F Frick, Scott D Reynolds, Thomas H KunzAbstract:Summary 1. Estimating variation in demographic rates, such as survival and fecundity, is important for testing life-history theory and identifying conservation and management goals. 2. We used 16 years (1993–2008) of mark–recapture data to estimate age-specific survival and breeding probabilities of the little brown Myotis Myotis lucifugus LeConte in southern New Hampshire, USA. Using Kendall & Nichols’ (1995) full-likelihood approach of the robust design to account for temporary emigration, we tested whether survival and breeding propensity is influenced by regional weather patterns and timing of reproduction. 3. Our results demonstrate that adult female survival of M. lucifugus ranged from 0AE63 (95% CL = 0AE56, 0AE68) to 0AE90 (95% CL = 0AE77, 0AE94), and was highest in wet years with high cumulative summer precipitation. First-year survival [range: 0AE23 (95% CL = 0AE14, 0AE35) to 0AE46 (95% CL = 0AE34, 0AE57)] was considerably lower than adult survival and depended on pup date of birth, such that young born earlier in the summer (c. late May) had a significantly higher probability of surviving their first year than young born later in the summer (c. mid-July). Similarly, the probability of young females returning to the maternity colony to breed in the summer following their birth year was higher for individuals born earlier in the summer [range: 0AE23 (95% CL = 0AE08, 0AE50) to 0AE53 (95% CL = 0AE30, 0AE75)]. 4. The positive influence of early parturition on 1st-year survival and breeding propensity demonstrates significant fitness benefits to reproductive timing in this temperate insectivorous bat. 5. Climatic factors can have important consequences for population dynamics of temperate bats, which may be negatively affected by summer drying patterns associated with global climate change. 6. Understanding long-term demographic trends will be important in the face of a novel disease phenomenon (White-Nose Syndrome) that is associated with massive mortalities in hibernating bat species, including M. lucifugus, in the northeastern United States.
Raphaël Arlettaz - One of the best experts on this subject based on the ideXlab platform.
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Cumulative number of bat passes per hour in relation to mean hourly wind speed at the truck-mounted crane.
2018Co-Authors: Sascha D. Wellig, Sébastien Nusslé, Daniela Miltner, Oliver Kohle, Olivier Glaizot, Veronika Braunisch, Martin K. Obrist, Raphaël ArlettazAbstract:a) all species pooled, b) Pipistrellus pipistrellus, c) Hypsugo savii, d) Myotis Myotis/Myotis blythii and e) Tadarida teniotis. The black line indicates 95% of the asymptote.
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Observed (up to 65 m a.g.l.) and projected (>65 m a.g.l.) vertical bat activity profiles (nightly average + SE–the latter expressing between night variation–with 95% confidence intervals of projections shaded in grey) constructed from the hourly numb
2018Co-Authors: Sascha D. Wellig, Sébastien Nusslé, Daniela Miltner, Oliver Kohle, Olivier Glaizot, Veronika Braunisch, Martin K. Obrist, Raphaël ArlettazAbstract:a) all species pooled, b) Pipistrellus pipistrellus, c) Hypsugo savii, d) Myotis Myotis/Myotis blythii and e) Tadarida teniotis. For more realistic representation the response variable is on the X axis, height a.g.l. being the vertical (Y) axis. The red dashed line represents the lower limit (50 m) of the rotor-swept zone as depicted by the rotor icon (not represented in 1e for enhacing clarity).
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echolocation and passive listening by foraging mouse eared bats Myotis Myotis and m blythii
The Journal of Experimental Biology, 2007Co-Authors: Danilo Russo, Gareth Jones, Raphaël ArlettazAbstract:SUMMARY The two sibling mouse-eared bats, Myotis Myotis and M. blythii , cope with similar orientation tasks, but separate their trophic niche by hunting in species-specific foraging microhabitats. Previous work has shown that both species rely largely on passive listening to detect and glean prey from substrates, and studies on other bat species have suggested that echolocation is `switched off9 during passive listening. We tested the hypothesis that mouse-eared bats continuously emit echolocation calls while approaching prey. Echolocation may be needed for orientation while simultaneously listening for prey. Because these sibling species forage in different microhabitats and eat different prey, we also compared their echolocation behaviour and related it to their ecology. Both species used echolocation throughout prey approach, corroborating a functional role for echolocation during gleaning. Captive bats of both species emitted similar orientation calls, and pulse rate increased during prey approach. Between the search to approach phases, call amplitude showed a sudden, dramatic drop and bats adopted `whispering echolocation9 by emitting weak calls. Whispering echolocation may reduce the risks of masking prey-generated sounds during passive listening, the mouse-eared bats9 main detection tactic; it may also avoid alerting ultrasound-sensitive prey. In several cases M. Myotis emitted a loud buzz made of 2-18 components when landing. We hypothesise that the buzz, absent in M. blythii at least when gleaning from the same substrate, is used to assess the distance from ground and refine the landing manoeuvre. Our findings have implications for niche separation between sibling species of echolocating bats, support a role for echolocation during passive listening and suggest a functional role for buzzes in landing control.
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Causal mechanisms underlying host specificity in bat ectoparasites.
Oecologia, 2004Co-Authors: Maud S. Giorgi, Raphaël Arlettaz, Frédéric Guillaume, Sébastien Nusslé, Carlo Ossola, Peter Vogel, Philippe ChristeAbstract:In parasites, host specificity may result either from restricted dispersal capacity or from fixed coevolutionary host-parasite adaptations. Knowledge of those proximal mechanisms leading to particular host specificity is fundamental to understand host-parasite interactions and potential coevolution of parasites and hosts. The relative importance of these two mechanisms was quantified through infection and cross-infection experiments using mites and bats as a model. Monospecific pools of parasitic mites (Spinturnix myoti and S. andegavinus) were subjected either to individual bats belonging to their traditional, native bat host species, or to another substitute host species within the same bat genus (Myotis). The two parasite species reacted differently to these treatments. S. myoti exhibited a clear preference for, and had a higher fitness on, its native host, Myotis Myotis. In contrast, S. andegavinus showed no host choice, although its fitness was higher on its native host M. daubentoni. The causal mechanisms mediating host specificity can apparently differ within closely related host-parasite systems.
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is the gibraltar strait a barrier to gene flow for the bat Myotis Myotis chiroptera vespertilionidae
Molecular Ecology, 2000Co-Authors: V Castella, Raphaël Arlettaz, Carlos F. Ibáñez, Manuel Ruedi, Laurent Excoffier, J. HausserAbstract:Because of their role in limiting gene flow, geographical barriers like mountains or seas often coincide with intraspecific genetic discontinuities. Although the Strait of Gibraltar represents such a potential barrier for both plants and animals, few studies have been conducted on its impact on gene flow. Here we test this effect on a bat species ( Myotis Myotis ) which is apparently distributed on both sides of the strait. Six colonies of 20 Myotis Myotis each were sampled in southern Spain and northern Morocco along a linear transect of 1350 km. Results based on six nuclear microsatellite loci reveal no significant population structure within regions, but a complete isolation between bats sampled on each side of the strait. Variability at 600 bp of a mitochondrial gene (cytochrome b ) confirms the existence of two genetically distinct and perfectly segregating clades, which diverged several million years ago. Despite the narrowness of the Gibraltar Strait (14 km), these molecular data suggest that neither males, nor females from either region have ever reproduced on the opposite side of the strait. Comparisons of molecular divergence with bats from a closely related species ( M. blythii ) suggest that the North African clade is possibly a distinct taxon warranting full species rank. We provisionally refer to it as Myotis cf punicus Felten 1977, but a definitive systematic understanding of the whole Mouse-eared bat species complex awaits further genetic sampling, especially in the Eastern Mediterranean areas.
Joseph S. Johnson - One of the best experts on this subject based on the ideXlab platform.
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population connectivity predicts vulnerability to white nose syndrome in the chilean Myotis Myotis chiloensis a genomics approach
bioRxiv, 2020Co-Authors: Thomas M Lilley, Tiina Savilammi, Gonzalo Ossa, Anna S Blomberg, Anti Vasemagi, Veronica Yung, David L J Vendrami, Joseph S. JohnsonAbstract:ABSTRACT Despite its peculiar distribution, the biology of the southernmost bat species in the world, the Chilean Myotis (Myotis chiloensis), has garnered little attention so far. The species has a north-south distribution of c. 2800 km, mostly on the eastern side of the Andes mountain range. Use of extended torpor occurs in the southernmost portion of the range, putting the species at risk of bat white-nose syndrome (WNS), a fungal disease responsible for massive population declines in North American bats. Here, we examined how geographic distance and topology would be reflected in the population structure of M. chiloensis along the majority of its range using a double digestion RAD-tag method. We sampled 66 individuals across the species range and discovered pronounced isolation-by-distance. Furthermore, and surprisingly, we found higher degrees of heterozygosity in the southernmost populations compared to the north. A coalescence analysis revealed that our populations may still not have reached secondary contact after the Last Glacial Maximum. As for the potential spread of pathogens, such as the fungus causing WNS, connectivity among populations was noticeably low, especially between the southern hibernatory populations in the Magallanes and Tierra del Fuego, and more northerly populations. This suggests the probability of geographic spread of the disease from the north through bat-to-bat contact to susceptible populations is low. The study presents a rare case of defined population structure in a bat species and warrants further research on the underlying factors contributing to this.
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immune responses in hibernating little brown Myotis Myotis lucifugus with white nose syndrome
Proceedings of The Royal Society B: Biological Sciences, 2017Co-Authors: Deeann M Reeder, Joseph S. Johnson, Thomas M Lilley, Jenni M Prokkola, E J Rogers, S Gronsky, Allen Kurta, Kenneth A FieldAbstract:White-nose syndrome (WNS) is a fungal disease responsible for decimating many bat populations in North America. Pseudogymnoascus destructans (Pd), the psychrophilic fungus responsible for WNS, prospers in the winter habitat of many hibernating bat species. The immune response that Pd elicits in bats is not yet fully understood; antibodies are produced in response to infection by Pd, but they may not be protective and indeed may be harmful. To understand how bats respond to infection during hibernation, we studied the effect of Pd inoculation on the survival and gene expression of captive hibernating Myotis lucifugus with varying pre-hibernation antifungal antibody titres. We investigated gene expression through the transcription of selected cytokine genes (Il6, Il17a, Il1b, Il4 and Ifng) associated with inflammatory, Th1, Th2 and Th17 immune responses in wing tissue and lymph nodes. We found no difference in survival between bats with low and high anti-Pd titres, although anti-Pd antibody production during hibernation differed significantly between infected and uninfected bats. Transcription of Il6 and Il17a was higher in the lymph nodes of infected bats compared with uninfected bats. Increased transcription of these cytokines in the lymph node suggests that a pro-inflammatory immune response to WNS is not restricted to infected tissues and occurs during hibernation. The resulting Th17 response may be protective in euthermic bats, but because it may disrupt torpor, it could be detrimental during hibernation.
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immune responses in hibernating little brown Myotis Myotis lucifugus with white nose syndrome
Proceedings of The Royal Society B: Biological Sciences, 2017Co-Authors: Deeann M Reeder, Joseph S. Johnson, Thomas M Lilley, Jenni M Prokkola, E J Rogers, S Gronsky, Allen Kurta, Kenneth A FieldAbstract:White-nose syndrome (WNS) is a fungal disease responsible for decimating many bat populations in North America. Pseudogymnoascus destructans (Pd), the psychrophilic fungus responsible for WNS, pros...
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sex and hibernaculum temperature predict survivorship in white nose syndrome affected little brown Myotis Myotis lucifugus
Royal Society Open Science, 2015Co-Authors: Laura E. Grieneisen, Sarah A Brownleebouboulis, Joseph S. Johnson, Deeann M ReederAbstract:White-nose syndrome (WNS), an emerging infectious disease caused by the novel fungus Pseudogymnoascus destructans, has devastated North American bat populations since its discovery in 2006. The little brown Myotis, Myotis lucifugus, has been especially affected. The goal of this 2-year captive study was to determine the impact of hibernacula temperature and sex on WNS survivorship in little brown Myotis that displayed visible fungal infection when collected from affected hibernacula. In study 1, we found that WNS-affected male bats had increased survival over females and that bats housed at a colder temperature survived longer than those housed at warmer temperatures. In study 2, we found that WNS-affected bats housed at a colder temperature fared worse than unaffected bats. Our results demonstrate that WNS mortality varies among individuals, and that colder hibernacula are more favourable for survival. They also suggest that female bats may be more negatively affected by WNS than male bats, which has important implications for the long-term survival of the little brown Myotis in eastern North America.
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host pathogen and environmental characteristics predict white nose syndrome mortality in captive little brown Myotis Myotis lucifugus
PLOS ONE, 2014Co-Authors: Joseph S. Johnson, Deeann M Reeder, James W Mcmichael, Melissa B Meierhofer, Daniel Wf Stern, Shayne S Lumadue, Lauren Sigler, Harrison D Winters, Megan E Vodzak, Allen KurtaAbstract:An estimated 5.7 million or more bats died in North America between 2006 and 2012 due to infection with the fungus Pseudogymnoascus destructans (Pd) that causes white-nose syndrome (WNS) during hibernation. The behavioral and physiological changes associated with hibernation leave bats vulnerable to WNS, but the persistence of bats within the contaminated regions of North America suggests that survival might vary predictably among individuals or in relation to environmental conditions. To investigate variables influencing WNS mortality, we conducted a captive study of 147 little brown Myotis (Myotis lucifugus) inoculated with 0, 500, 5 000, 50 000, or 500 000 Pd conidia and hibernated for five months at either 4 or 10°C. We found that female bats were significantly more likely to survive hibernation, as were bats hibernated at 4°C, and bats with greater body condition at the start of hibernation. Although all bats inoculated with Pd exhibited shorter torpor bouts compared to controls, a characteristic of WNS, only bats inoculated with 500 conidia had significantly lower survival odds compared to controls. These data show that host and environmental characteristics are significant predictors of WNS mortality, and that exposure to up to 500 conidia is sufficient to cause a fatal infection. These results also illustrate a need to quantify dynamics of Pd exposure in free-ranging bats, as dynamics of WNS produced in captive studies inoculating bats with several hundred thousand conidia may differ from those in the wild.
Deeann M Reeder - One of the best experts on this subject based on the ideXlab platform.
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immune responses in hibernating little brown Myotis Myotis lucifugus with white nose syndrome
Proceedings of The Royal Society B: Biological Sciences, 2017Co-Authors: Deeann M Reeder, Joseph S. Johnson, Thomas M Lilley, Jenni M Prokkola, E J Rogers, S Gronsky, Allen Kurta, Kenneth A FieldAbstract:White-nose syndrome (WNS) is a fungal disease responsible for decimating many bat populations in North America. Pseudogymnoascus destructans (Pd), the psychrophilic fungus responsible for WNS, pros...
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immune responses in hibernating little brown Myotis Myotis lucifugus with white nose syndrome
Proceedings of The Royal Society B: Biological Sciences, 2017Co-Authors: Deeann M Reeder, Joseph S. Johnson, Thomas M Lilley, Jenni M Prokkola, E J Rogers, S Gronsky, Allen Kurta, Kenneth A FieldAbstract:White-nose syndrome (WNS) is a fungal disease responsible for decimating many bat populations in North America. Pseudogymnoascus destructans (Pd), the psychrophilic fungus responsible for WNS, prospers in the winter habitat of many hibernating bat species. The immune response that Pd elicits in bats is not yet fully understood; antibodies are produced in response to infection by Pd, but they may not be protective and indeed may be harmful. To understand how bats respond to infection during hibernation, we studied the effect of Pd inoculation on the survival and gene expression of captive hibernating Myotis lucifugus with varying pre-hibernation antifungal antibody titres. We investigated gene expression through the transcription of selected cytokine genes (Il6, Il17a, Il1b, Il4 and Ifng) associated with inflammatory, Th1, Th2 and Th17 immune responses in wing tissue and lymph nodes. We found no difference in survival between bats with low and high anti-Pd titres, although anti-Pd antibody production during hibernation differed significantly between infected and uninfected bats. Transcription of Il6 and Il17a was higher in the lymph nodes of infected bats compared with uninfected bats. Increased transcription of these cytokines in the lymph node suggests that a pro-inflammatory immune response to WNS is not restricted to infected tissues and occurs during hibernation. The resulting Th17 response may be protective in euthermic bats, but because it may disrupt torpor, it could be detrimental during hibernation.
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pharmacokinetics of terbinafine in little brown Myotis Myotis lucifugus infected with pseudogymnoascus destructans
American Journal of Veterinary Research, 2017Co-Authors: Michael H Court, Alison H Robbins, Anne M Whitford, Erika V Beck, Flo S Tseng, Deeann M ReederAbstract:OBJECTIVE To determine the pharmacokinetics of terbinafine in little brown Myotis (Myotis lucifugus) infected with Pseudogymnoascus destructans. ANIMALS 123 bats from a P destructans–infected hibernation site in Virginia. PROCEDURES 3 bats were euthanized and necropsied to confirm the presence of P destructans within the population. The remaining 120 bats were systematically assigned to 6 groups (20 bats/group). Bats in each of 3 groups received 6, 20, or 60 mg of terbinafine/kg, SC, once daily for 10 days. Bats in another group received 200 mg of terbinafine/kg, SC, once daily for 5 days. Bats in 1 group received the terbinafine vehicle solution (0.1 mL/kg, SC, once daily for 10 days). Bats in the remaining group did not receive any treatment. Following the treatment period (days 1 through 10), bats were housed in a hibernation chamber and monitored daily until euthanasia on day 42, 75, or 109. Tissue specimens were collected from all bats as soon as possible after death or euthanasia to determine terbin...
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sex and hibernaculum temperature predict survivorship in white nose syndrome affected little brown Myotis Myotis lucifugus
Royal Society Open Science, 2015Co-Authors: Laura E. Grieneisen, Sarah A Brownleebouboulis, Joseph S. Johnson, Deeann M ReederAbstract:White-nose syndrome (WNS), an emerging infectious disease caused by the novel fungus Pseudogymnoascus destructans, has devastated North American bat populations since its discovery in 2006. The little brown Myotis, Myotis lucifugus, has been especially affected. The goal of this 2-year captive study was to determine the impact of hibernacula temperature and sex on WNS survivorship in little brown Myotis that displayed visible fungal infection when collected from affected hibernacula. In study 1, we found that WNS-affected male bats had increased survival over females and that bats housed at a colder temperature survived longer than those housed at warmer temperatures. In study 2, we found that WNS-affected bats housed at a colder temperature fared worse than unaffected bats. Our results demonstrate that WNS mortality varies among individuals, and that colder hibernacula are more favourable for survival. They also suggest that female bats may be more negatively affected by WNS than male bats, which has important implications for the long-term survival of the little brown Myotis in eastern North America.
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host pathogen and environmental characteristics predict white nose syndrome mortality in captive little brown Myotis Myotis lucifugus
PLOS ONE, 2014Co-Authors: Joseph S. Johnson, Deeann M Reeder, James W Mcmichael, Melissa B Meierhofer, Daniel Wf Stern, Shayne S Lumadue, Lauren Sigler, Harrison D Winters, Megan E Vodzak, Allen KurtaAbstract:An estimated 5.7 million or more bats died in North America between 2006 and 2012 due to infection with the fungus Pseudogymnoascus destructans (Pd) that causes white-nose syndrome (WNS) during hibernation. The behavioral and physiological changes associated with hibernation leave bats vulnerable to WNS, but the persistence of bats within the contaminated regions of North America suggests that survival might vary predictably among individuals or in relation to environmental conditions. To investigate variables influencing WNS mortality, we conducted a captive study of 147 little brown Myotis (Myotis lucifugus) inoculated with 0, 500, 5 000, 50 000, or 500 000 Pd conidia and hibernated for five months at either 4 or 10°C. We found that female bats were significantly more likely to survive hibernation, as were bats hibernated at 4°C, and bats with greater body condition at the start of hibernation. Although all bats inoculated with Pd exhibited shorter torpor bouts compared to controls, a characteristic of WNS, only bats inoculated with 500 conidia had significantly lower survival odds compared to controls. These data show that host and environmental characteristics are significant predictors of WNS mortality, and that exposure to up to 500 conidia is sufficient to cause a fatal infection. These results also illustrate a need to quantify dynamics of Pd exposure in free-ranging bats, as dynamics of WNS produced in captive studies inoculating bats with several hundred thousand conidia may differ from those in the wild.
Jordi Serracobo - One of the best experts on this subject based on the ideXlab platform.
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seroprevalence of toscana virus and sandfly fever sicilian virus in european bat colonies measured using a neutralization test
Viruses, 2021Co-Authors: Nazli Ayhan, Rémi N. Charrel, Marc Lopezroig, Abir Monastiri, Jordi SerracoboAbstract:Toscana phlebovirus (TOSV) and Sicilian phlebovirus (SFSV) are endemic in the Mediterranean area where they are transmitted to humans by infected sandflies. Vertebrates of several species have been postulated to act as reservoirs of these viruses, but convincing evidence is still awaited. Among them, bats have been suggested, however documented evidence is lacking. Here we tested a total of 329 bats belonging to eight species collected from twelve localities in southern Spain for the presence of neutralizing antibodies specific to TOSV and SFSV. Positive sera were detected in Schreiber's long-fingered bat (Miniopterus schreibersii), mouse-eared Myotis (Myotis Myotis), European free-tailed bat (Tadarida teniotis), and common serotine (Eptesicus serotinus) with the latter showing the highest prevalence rates for SFSV (22.6%) and TOSV (10%). There was no difference between females and males. Results suggest that bats are not likely to play a major role in the natural cycle of these two sandfly-borne phleboviruses. However, large breeding colonies of bats can be used as sentinels for surveillance of the presence of such viruses in a given locality. In addition, capture-recapture studies should be initiated in order to understand better the dynamics of TOSV and SFSV in bat populations.
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temporal dynamics of european bat lyssavirus type 1 and survival of Myotis Myotis bats in natural colonies
PLOS ONE, 2007Co-Authors: Hervé Bourhy, Blanca Amengual, Marc Lopezroig, Jordi SerracoboAbstract:Many emerging RNA viruses of public health concern have recently been detected in bats. However, the dynamics of these viruses in natural bat colonies is presently unknown. Consequently, prediction of the spread of these viruses and the establishment of appropriate control measures are hindered by a lack of information. To this aim, we collected epidemiological, virological and ecological data during a twelve-year longitudinal study in two colonies of insectivorous bats (Myotis Myotis) located in Spain and infected by the most common bat lyssavirus found in Europe, the European bat lyssavirus subtype 1 (EBLV-1). This active survey demonstrates that cyclic lyssavirus infections occurred with periodic oscillations in the number of susceptible, immune and infected bats. Persistence of immunity for more than one year was detected in some individuals. These data were further used to feed models to analyze the temporal dynamics of EBLV-1 and the survival rate of bats. According to these models, the infection is characterized by a predicted low basic reproductive rate (R0 = 1.706) and a short infectious period (D = 5.1 days). In contrast to observations in most non-flying animals infected with rabies, the survival model shows no variation in mortality after EBLV-1 infection of M. Myotis. These findings have considerable public health implications in terms of management of colonies where lyssavirus-positive bats have been recorded and confirm the potential risk of rabies transmission to humans. A greater understanding of the dynamics of lyssavirus in bat colonies also provides a model to study how bats contribute to the maintenance and transmission of other viruses of public health concern.
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european bat lyssavirus infection in spanish bat populations
Emerging Infectious Diseases, 2002Co-Authors: Jordi Serracobo, Blanca Amengual, Carlos Abellan, Hervé BourhyAbstract:From 1992 to 2000, 976 sera, 27 blood pellets, and 91 brains were obtained from 14 bat species in 37 localities in Spain. Specific anti-European bat lyssavirus 1 (EBL1)-neutralizing antibodies have been detected in Myotis Myotis, Miniopterus schreibersii, Tadarida teniotis, and Rhinolophus ferrumequinum in the region of Aragon and the Balearic Islands. Positive results were also obtained by nested reverse transcription-polymerase chain reaction on brain, blood pellet, lung, heart, tongue, and esophagus-larynxpharynx of M. Myotis, Myotis nattereri, R. ferrumequinum, and M. schreibersii. Determination of nucleotide sequence confirmed the presence of EBL1 RNA in the different tissues. In one colony, the prevalence of seropositive bats over time corresponded to an asymmetrical curve, with a sudden initial increase peaking at 60% of the bats, followed by a gradual decline. Banded seropositive bats were recovered during several years, indicating that EBL1 infection in these bats was nonlethal. At least one of this species (M. schreibersii) is migratory and thus could be partially responsible for the dissemination of EBL1 on both shores of the
