Vampire Bat Research Articles

A chiropteran factor of innate immunity can be recruited for rapid rescue and amplification of recombinant modified vaccinia Ankara (MVA).

Pharmacological characterization of vampire bat-derived CGRP at the human CGRP receptor in the Xenopus oocyte system.

BackgroundRabies is an acute and progressive viral zoonotic disease of the nervous system, which widely affects domestic animals in Latin America. Vampire bat-borne rabies virus (RABV) has significant negative impacts on the livestock industry via animal mortality. Nevertheless, the landscape level factors that facilitate or limit RABV transmission from vampire bats to livestock remain elusive.MethodsTo determine how abiotic and biotic factors modulate RABV spillover from vampire bats to livestock, we assessed the role of different landscape variables on the occurrence of RABV spillover from Desmodus rotundus to livestock in Colombia. Using ecological niche modeling as the theoretical and analytical framework, we analyzed ecological and epidemiological RABV data to reconstruct spillover transmission events.ResultsAnthropogenic variables including livestock and human density were consistently selected as predictors of RABV spillover from vampire bats to livestock. Cattle density had the highest average relative contribution to final ecological niche models (64.7%). We also found improvement of RABV spillover risk estimates when sampling bias in the form of cattle density was used in the modeling process. High risk for RABV spillover (0.75-0.98) was consistently predicted in the Caribbean region of Colombia. Nevertheless, more widespread moderate RABV spillover risk was predicted more broadly across the country when sampling bias was accounted for.ConclusionOur modelling effort revealed that variable selection and use of bias surface have tractable impacts on final projections of spillover risk. Our results also indicate that human activity drives RABV spillover risk to a greater extent than ecological or climatological factors. Results from this study provide important information about landscape conditions linked to RABV transmission risk, where livestock vaccination should be prioritized.

Space-time clustering of rabies in equines in Brazil from 2006 to 2023.

We reported the interaction between a common vampire bat (Desmodus rotundus) and a greater naked-tailed armadillo (Cabassous tatouay) recorded by camera traps in an Atlantic Forest remnant called ‘Mata da Sucupira Torta’ in Paraíba state, Brazil, in September 2023. This documented biological interaction corroborates the high plasticity of D. rotundus in the search for prey and underscores the urgency of understanding the processes that structure predator-prey relationships, especially in areas increasingly impacted by human activities. This observation also highlights the importance of using alternative methods to address gaps in our understanding of the ecological dynamics between predators and prey.

Even though bats are the second most speciose group of mammals, neuroanatomical studies of their hippocampus are rare, particularly of small echolocating bats. Here, we provide a qualitative and quantitative neuroanatomical analysis of the hippocampus of small echolocating bats (Phyllostomidae and Vespertilionidae). Calcium-binding proteins revealed species- and family-specific patterns for calbindin and calretinin. Interneuron staining for both proteins was very rare in phyllostomids, while calretinin marked subpopulations of CA3 pyramidal neurons in both families. Parvalbumin expression was consistent across bats and similar to other species. A unique calretinin-positive calbindin-negative zone was observed at the superficial boundary of the CA3 pyramidal cell layer in phyllostomid bats. This zone defined a gap between pyramidal cells and the zinc-positive mossy fibers. We hypothesize that this gap might either stem from calretinin-positive afferents displacing the zinc-positive mossy fiber boutons, or from a complete segregation of neurochemically distinct mossy boutons. Furthermore, we observed a distinct dorsoventral shift in the length of the upper and lower blade of the granule cell layer in all species. In terms of hippocampal neuron numbers, bats were characterized by a rather small granule cell and subicular neuron population, but a well-developed CA3. In a correspondence analysis, preferred diet segregated phyllostomids into a hilus-dominant omnivorous and frugivorous species group, and a subiculum-dominant group containing vampire bats and nectivorous species. Although the two families overlapped considerably, the cellular composition of the phyllostomid hippocampus can be described as output dominant, while in vespertilionids neuron populations on the hippocampal input side are more dominant. Neuroanatomical and ecological variability and unique traits within echolocating bats as shown here can provide a rich source for investigating structure-function relationships.

Habitat fragmentation can have negative impacts on wildlife including increased risk of infectious disease. To assess spatiotemporal changes in pathogen dynamics in vampire bats (Desmodus rotundus) in response to habitat fragmentation, we used general linear mixed models to investigate the influence of site, year, and tree cover on the prevalence ofBartonellaand hemotropicMycoplasma(hemoplasma) in bats in one large and one small forest fragment in northern Belize across seven years.Bartonellawas marginally more prevalent in later years, while year and site differences in hemoplasma infections were driven by a peak in prevalence in the third year of the study in the small fragment.Bartonellaprevalence increased with forest loss, but only in the large fragment, whereas hemoplasma prevalence showed a marginal negative response to forest loss. The effects of site, year, and forest loss on infection likelihood varied by pathogen genotype. Neither site nor year affectedBartonellagenotypes, but one genotype was positively associated with tree cover. Two hemoplasma genotypes were influenced by year, but with differing trends. One genotype increased with tree cover regardless of site while another increased with forest loss at the small fragment only. Our work demonstrates that the effects of habitat fragmentation on infection prevalence depended on both the pathogen and specific genotype. Our findings complicate expectations of how habitat fragmentation affects infectious disease dynamics in bats. As such, management practices aimed at mitigating the impacts of infectious diseases in fragmented systems should be tailored to specific pathogens of concern.

Derived from an extensive survey on the common vampire bat Desmodus rotundus (Geoffroy, 1810) in some localities along the Central region, and the Pacific and Atlantic slopes of Mexico, Chirodiscid fur mites of the genus Alabidocarpus were found exclusively in the country's southern region in the state of Oaxaca, where they turned out to be a new species. Here, we describe the adults and juveniles of this new Chirodiscid species. The present study increases the number of species of Alabidocarpus associated with American bats to seven; therefore, we include an updated key to known species in the American continent.

Spatial distribution of bat-related complaints and bloodmeal sources of the common vampire Bat (Desmodus rotundus) in the City of Salvador, Bahia, Brazil

Dietary variation in a family group of the woolly false vampire Bat (Chrotopterus auritus, Phyllostomidae) at the north of its distribution

Rabies is one of the zoonoses with the most significant impact on domestic herbivores, representing a mortality of 100,000 individuals and an economic loss of US$97 million per year in Latin America. The common vampire bat (Desmodus rotundus) is the primary reservoir for livestock rabies and is naturally distributed in Latin America. The concern arises from the possibility that climate change could facilitate the species' arrival to the southern USA. In this study, we used ecological niche modeling to estimate the distribution of D. rotundus in the present time and under future climate change scenarios. We analyzed whether rabies cases in Mexico were related to D. rotundus climatic suitability, and other factors such as livestock density and an ecological impact index. Our results suggest that climate change could facilitate the colonization of new sites in northern Mexico and the southern USA, which could threaten animal and human health. Further, we found that rabies cases are explained mainly by the reservoir suitability. However, national- and state-level policies may also play a key role in explaining the rabies cases in Mexico. There is a possibility that D. rotundus may expand its range to northern and northeastern Mexico, implying a high risk for the presence of rabies virus-free areas in the southern USA.

Genetic diversity of Bartonella spp. in vampire bats and associated Streblidae bat flies in the Brazilian Amazon.

In humans and other mammals, the detection and signal transduction of the taste qualities sweet, umami and bitter is mediated by G protein‐coupled receptors. Besides the oral cavity, where they are responsible for a first evaluation of ingested food, their expression was further proven in several non‐gustatory tissues like the gastrointestinal tract, the heart, and the respiratory tract. This knowledge hints to further physiological functions of taste receptors beside taste perception. However, nowadays only a few of these functions, and the involved agonists, are known.As taste receptors are rather insensitive and in the case of bitter taste receptors, called TAS2Rs, the ingestion of high concentrations of bitter substances is avoided by their bitter taste, it is questionable whether compounds that are ingested by food will frequently reach non‐gustatory TAS2Rs in concentrations sufficient for activation. Therefore, the question arises by which substances extra‐oral bitter taste receptors are activated. One aim of this thesis was the elucidation of the potential of endogenous substances or metabolites to activate bitter taste receptors.Nowadays, bioinformatics is an important tool in research. Modeling studies can be an appropriate alternative assisting in‐vitro experiments to speed up the identification of potent endogenous agonists. Nevertheless, knowledge of receptor structures is a key requirement for accurate modeling. Until recently, no experimental structure of bitter taste receptors was elucidated. Therefore, receptor models were based on homology modeling with related G protein‐coupled receptors, even though sequence identities are not completely overlapping. To contribute to improvement of receptor models, amino acid positions that are important for agonist binding and receptor activation were summarized in a review.Furthermore, the conservation of receptor responses was investigated. In evolution, individuals, which have an advantage over their conspecifics, are selected. Therefore, conservation of agonists in species that divided millions of years ago can hint to the importance of these agonists. In recent studies, the activation of human TAS2R7 by di‐ and trivalent metal ions was shown. The expression of the one‐to‐one orthologous receptor of the vampire bat in a cell culture model showed the conservation of metal ion response in this species. This information may indicate that the excessive consumption of metal ions has a harmful effect on mammals and should therefore be avoided. Nevertheless, metal ions are involved in several processes in the body. For example, they act as cofactors in enzymes or as second messengers in cellular signaling cascades. Therefore, high metal ion concentrations can be present locally, which may result in activation of the TAS2R7 in non‐gustatory tissues.The bitter taste of the body fluid bile has long been known. To elucidate, which human bitter taste receptors are addressed by the compound class of bile acids, 25 functional human TAS2Rs were expressed in cell culture models and their activation was measured after application of several bile acids. In doing so, five of these receptors were identified as bile acid receptors. By measuring dose‐response relationships, an overlap of endogenous bile acid concentrations and threshold concentrations for bitter taste receptor activation was detected. As already mentioned, conservation of biological processes can hint to the relevance of these processes for the well‐being of animals. For this reason, this experimental design was applied to 34 mouse bitter taste receptors. Thereby, six receptors that responded to bile acids were deciphered.Finally, this thesis shows that non‐gustatory bitter taste receptors are activated by essential endogenous substances, which are present in the human body in concentrations that suffice to activate TAS2Rs. The task for future researchers will be to use this knowledge to elucidate biological effects of extra‐oral bitter taste receptor activation. This information will be useful for the food to develop dietary supplements for human well‐being and for the pharma industry to identify new pharmacological targets to address diseases.

Transporting Common Vampire Bats (<i>Desmodus rotundus</i>) by Land: Design of a Transport Container and Care During Transit

Bats are important reservoirs of paramyxoviruses, yet their role in the evolutionary origins of viruses pertaining to the paramyxoviral genus Morbillivirus, such as measles virus, remains unclear. Here, combining field surveys and data mining, we identified six divergent morbilliviruses by investigating wild bats (38/1,629 RT-PCR-positive) and non-human primates (NHP, 13/1,370 RT-PCR-positive) in Brazil and Costa Rica over 14 years. High morbillivirus concentrations of up to 109 RNA copies per g and RNA staining in different organs suggested systemic infection. Of 117 vampire bats, 35.9% had neutralizing antibodies against a primary vampire bat morbillivirus isolate, suggesting frequent non-fatal infections. In vitro assays using bat CD150 for cell entry and partial cross-neutralization of bat-associated morbillivirus by heterologous sera suggested conserved entry and antigenicity. NHP-associated, but not bat-associated morbilliviruses, used human CD150 and nectin-4 cellular receptors, suggesting differential zoonotic potential. Macroevolutionary reconstructions revealed predominance of Neotropical bat hosts during morbilliviral diversification, including bat-associated host shifts into Mexican pigs and Brazilian NHPs. These data argue for increased surveillance, experimental risk assessments and intervention strategies to mitigate risks of reservoir-bound morbilliviruses shifting hosts.

The study of bats in India is often viewed as limited and underexplored. In 1810, French scientist E. Geoffroy published the first scientific description of the bat fauna of India, focusing on Lyroderma lyra sp. also known as Greater false vampire bat from Madras.This account is deemed the first documentation of the bat species present in the country. Subsequently, Hinton and Lindsay (1926) and Sinha (1999) reported sightings of the species in the few localities of Assam. The current research pinpointed three distinct roost sites (S-A; S-B; S-C) where L. lyra has been observed to roost in varied habitats. The species recorded from three distinct locations exhibits an average forearm length of 68.1±1.76 mm and an average body mass of 55.6±4.04 g. Lyroderma lyra is recognized by its bifid tragus and a long, upright, and simple noseleaf measuring 10. 8± 0.7 mm, which is significantly larger than the 6.5 mm noseleafin comparision to M. spasma (the other species in the Megadermatidae family). L. lyra, part of the Megadermatidae family, uses vision and passive listening to hunt prey, even in complete darkness.It plays a crucial role in pest and bio-resource management, regulating insect populations in forests and agro-ecosystems.

Epidemiological and molecular analysis of a rabies outbreak in the state of bahia, Brazil.

As a significant zoonotic disease, rabies poses substantial economic challenges for the livestock sector, highlighting the need for effective wildlife monitoring as part of a One Health approach. This study documents the first case of paralytic rabies in a lowland tapir (Tapirus terrestris) at the Guaycolec Wildlife Station in Formosa, Argentina. The 12-year-old male tapir exhibited neurological symptoms, including limb paralysis and dysphagia, leading to its death. The rabies virus was confirmed through direct immunofluorescence, virus isolation in BHK-21 cells, and molecular diagnostics via real-time RT-PCR and conventional PCR. Antigenic variant 3, associated with Desmodus rotundus, was identified. Histopathological examination revealed non-suppurative encephalitis with lymphocytic perivascular cuffs, neuronal vacuolization, and acidophilic intracytoplasmic inclusion bodies in the grey matter. This case underscores the importance of expanded surveillance for non-traditional hosts, as it demonstrates the potential for rabies transmission in changing environments. The findings highlight the need to maintain epidemiological surveillance systems at the wildlife-livestock-human interface and to develop targeted control strategies to mitigate the spread of rabies, particularly in areas where vampire bat populations are subject to anthropogenic pressures. Comprehensive monitoring and early detection are essential for effective rabies management in both wildlife and urban contexts.

During the COVID-19 pandemic, severe acute respiratory syndrome coronavirus 2 (SC2) infection was confirmed in various animal species demonstrating a wide host range of the virus. Prior studies have shown that the ACE2 protein is the primary receptor used by the virus to gain cellular entry and begin the replication cycle. In previous studies, we demonstrated that human and various bat ACE2 proteins can be utilized by SC2 viruses for entry. Bats are a suspected natural host of SC2 because of genetic homology with other bat coronaviruses. In this work, we demonstrate that expression of ACE2 genes from the common vampire bat (CVB) (Desmodus rotundus) and the pallid bat (PB) (Antrozous pallidus), supports infection and replication of some SC2 viruses in cell culture. Two cell lines were produced, CVB-ACE2 and PB-ACE2, expressing ACE2 from these bat species along with human TMPRSS2, in a model previously established using a non-permissive chicken DF-1 cell line. Results demonstrate that the original Wuhan lineage (WA1) virus and the Delta variant were able to infect and replicate in either of the bat ACE2 cell lines. In contrast, the Lambda and Omicron variant viruses infected both cell lines, but viral titers did not increase following infection. Viral detection using immunofluorescence demonstrated abundant spike (S) protein staining for the WA1 and Delta variants but little signal for the Lambda and Omicron variants. These studies demonstrate that while ACE2 from CVB and PB can be utilized by SC2 viruses to gain entry for infection, later variants (Lambda and Omicron) replicate poorly in these cell lines. These observations suggest more efficient human adaption in later SC2 variants that become less fit for replication in other animal species.

The woolly false- vampire bat, Chrotopterus auritus, is a large carnivorous bat with a wide distribution in the Americas. Besides roosting in hollow trees and caves, this bat makes use of Mayan archaeological sites in the Yucatan Peninsula, where it is threatened. Understanding the microclimatic conditions that allow this species to exploit these roosts is important in the face of increasing anthropogenic change in the region, such as land development and tourist accommodations in archaeological sites, which could threaten their suitability. We used temperature and relative humidity data loggers to record the internal temperature and relative humidity and external temperature of three Mayan temple roosts in Calakmul, Campeche, expecting internal conditions to be, on average, close to the reported thermoneutral zone of the species (~27-34 °C). We recorded 54,7 days of temperature data and 42,5 days of relative humidity data in four different months of the year. The yearly average internal temperature of the roosts was 24,6 °C (SD=2,03), while yearly average internal relative humidity was 79,4 % (SD=8,3), with significant differences between roosts and between sampling months. Chrotopterus auritus tolerates energetically suboptimal conditions, potentially prioritising other factors in its selection of roosts.