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1.
J Zoo Wildl Med ; 55(2): 393-403, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38875195

RÉSUMÉ

Megachiroptera is a mammalian suborder that includes old world fruit bats. Common clinical problems among captive Megachiroptera, such as liver disease (e.g., iron storage disease), kidney disease (e.g., protein-losing nephropathy), and heart disease (e.g., dilated cardiomyopathy), carry elevated risk for hemostatic derangements. The assessment of viscoelastic coagulation assays, however, has not yet been reported in bats. The main objective of the study was to describe viscoelastography data using the Viscoelastic Coagulation Monitor (VCM) Vet in captive large flying foxes (Pteropus vampyrus) (n = 20) and variable flying foxes (Pteropus hypomelanus) (n = 10). Additional objectives were to compare viscoelastic and clotting parameters (1) between healthy P. vampyrus and P. hypomelanus bats and (2) between untreated bats and those treated with meloxicam or aspirin, and (3) to examine relationships between activated partial thromboplastin time (aPTT) and potentially homologous viscoelastic parameters clotting time (CT) and clot formation time (CFT). The results showed marked variability among clinically normal bats. The intrinsic pathway, as measured by aPTT, had prolonged times compared with most terrestrial mammals, but similar times to birds, marine mammals, and sea turtles. A search of P. vampyrus genome found stop codons present in two exons of the factor XI gene; alterations in factor XI expression would be expected to alter intrinsic coagulation. Because of the high variability, no statistically significant findings were noted in the secondary objectives. Correlation between aPTT and CT or CFT was not strong (rs = 0.406 or 0.192, respectively). The results from this study suggest that clot kinetics vary widely among Megachiroptera when using the VCM Vet with untreated blood. A prolonged intrinsic coagulation pathway, as has been found in other megachiropteran species, and activation of the extrinsic coagulation pathway during venipuncture may be responsible for the inconsistent results.


Sujet(s)
Chiroptera , Animaux , Chiroptera/sang , Coagulation sanguine/physiologie , Tests de coagulation sanguine/médecine vétérinaire , Femelle , Mâle
2.
Dokl Biol Sci ; 516(1): 36-41, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38619736

RÉSUMÉ

The pool of free amino acids (AAs) in the blood serum was studied in two European migratory bat species, Vespertilio murinus and Pipistrellus nathusii, of the Urals. Bats from this year's bloods were examined, and significant differences were observed in main metabolic groups of free AAs, including glycogenic (GGAAs), nonessential (NEAAs), essential (EAAs), and sulfur-containing (SCAAs) AAs (p < 0.05). Based on the percent content of the metabolic groups in the total AA pool, GGAAs (79.7%) and EAAs (49.4%) were found to predominate in P. nathusii, and GGAAs (74.9%) and NEAAs (58.4%), in V. murinus. No difference in AAA and BCAA contents was observed between V. murinus and P. nathusii (p > 0.05). The migratory species were shown to significantly differ in the metabolic groups of serum AAs from the resident species Myotis dasycneme (p < 0.05).


Sujet(s)
Acides aminés , Migration animale , Chiroptera , Animaux , Chiroptera/sang , Acides aminés/sang , Migration animale/physiologie
3.
Braz. j. biol ; 83: 1-6, 2023. graf, tab
Article de Anglais | LILACS, VETINDEX | ID: biblio-1468830

RÉSUMÉ

Bats are important for the homeostasis of ecosystems and serve as hosts of various microorganisms including bacteria, viruses, and fungi with pathogenic potential. This study aimed to isolate fungi from biological samples obtained from bats captured in the city of Sinop (state of Mato Grosso, Brazil), where large areas of deforestation exist due to urbanization and agriculture. On the basis of the flow of people and domestic animals, 48 bats were captured in eleven urban forest fragments. The samples were processed and submitted to microbiological cultures, to isolate and to identify the fungal genera. Thirty-four (70.83%) of the captured bats were positive for fungi; 18 (37.5%) and 16 (33.33%) of these bats were female and male, respectively. Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp., and Candida sp., which may cause opportunistic infections, were isolated. The bat species with the highest number of fungal isolates was Molossus molossus: 21 isolates (43.8%). According to our results, bats captured in urban forest fragments in Sinop harbor pathogenic fungi, increasing the risk of opportunistic fungal infections in humans and domestic animals.


Os morcegos apresentam grande importância na homeostasia dos ecossistemas e são hospedeiros de uma rica diversidade de micro-organismos como bactérias, vírus e fungos com potencial patogênico. Portanto, este estudo visou isolar fungos presentes em amostras biológicas de morcegos na cidade de Sinop - MT, que possui grandes áreas de desmatamento devido à urbanização e agricultura. Foram capturados 48 morcegos de diferentes espécies, em onze fragmentos florestais urbanos definidos de acordo com fluxo de pessoas e animais domésticos, para obtenção de amostras biológicas. Essas amostras foram processadas e submetidas aos cultivos microbiológicos, para isolamento e identificação dos gêneros dos fungos. Dos 48 morcegos, 34 (70,83%) foram positivos para pelos menos um gênero de fungo, sendo 18 (37,5%) fêmeas e 16 (33,33%) machos, e os gêneros isolados a partir das amostras biológicas foram Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp. e Candida sp., que podem ser causadores de infecções oportunistas. Desse total, a espécie que apresentou maior positividade para pelo menos um gênero de fungo foi Molossus molossus com 21 (43,8%). Nossos resultados demonstram que os morcegos capturados nos fragmentos florestais urbanos na cidade de Sinop - MT, podem atuar como agentes veiculadores de fungos com potencial patogênico, aumentando assim o risco de exposição e aquisição de infecções fúngicas oportunistas por pessoas e animais domésticos.


Sujet(s)
Animaux , Champignons/pathogénicité , Chiroptera/microbiologie , Chiroptera/sang , Alternaria , Aspergillus , Candida , Cryptococcus , Fusarium , Penicillium , Scopulariopsis , Trichosporon
4.
J Med Virol ; 94(2): 771-775, 2022 02.
Article de Anglais | MEDLINE | ID: mdl-34708881

RÉSUMÉ

Pteropine orthoreovirus (PRV) is an emerging zoonotic respiratory virus that can be transmitted from bats to humans. In Malaysia, aside from PRV2P (Pulau virus) being isolated from Pteropus hypomelanus sampled in Tioman Island, PRV3M (Melaka virus), PRV4K (Kampar virus), and PRV7S (Sikamat virus) were all isolated from samples of patients who reported having a disease spectrum from acute respiratory distress to influenza-like illness and sometimes even with enteric symptoms such as diarrhea and abdominal pain. Screening of sera collected from human volunteers on Tioman Island in 2001-2002 demonstrated that 12.8% (14/109) were positive for PRV2P and PRV3M. Taking all these together, we aim to investigate the serological prevalence of PRV (including PRV4K and PRV7S) among Tioman Island inhabitants again with the assumption that the seroprevalence rate will remain nearly similar to the above reported if human exposure to bats is still happening in the island. Using sera collected from human volunteers on the same island in 2017, we demonstrated seroprevalence of 17.8% (28/157) against PRV2P and PRV3M, respectively. Seropositivity of 11.4% among Tioman Island inhabitants against PRV4K and PRV7S, respectively, was described in this study. In addition, the seroprevalence of 89.5% (17/19), 73.6% (14/19), 63.0% (12/19), and 73.6% (14/19) against PRV2P, PRV3M, PRV4K, and PRV7S, respectively, were observed among pteropid bats in the island. We revealed that the seroprevalence of PRV among island inhabitants remains nearly similar after nearly two decades, suggesting that potential spill-over events in bat-human interface areas in the Tioman Island. We are unclear whether such spillover was directly from bats to humans, as suspected for the PRV3M human cases, or from an intermediate host(s) yet to be identified. There is a high possibility of the viruses circulating among the bats as demonstrated by high seroprevalence against PRV in the bats.


Sujet(s)
Chiroptera/virologie , Orthoreovirus/génétique , Orthoreovirus/physiologie , Infections à Reoviridae/médecine vétérinaire , Zoonoses/transmission , Adolescent , Adulte , Animaux , Anticorps antiviraux/sang , Anticorps antiviraux/immunologie , Chiroptera/sang , Femelle , Volontaires sains , Humains , Malaisie , Mâle , Adulte d'âge moyen , Infections à Reoviridae/virologie , Études séroépidémiologiques , Jeune adulte , Zoonoses/sang , Zoonoses/virologie
5.
Front Immunol ; 12: 735866, 2021.
Article de Anglais | MEDLINE | ID: mdl-34790193

RÉSUMÉ

Bats are the only mammals with self-powered flight and account for 20% of all extant mammalian diversity. In addition, they harbor many emerging and reemerging viruses, including multiple coronaviruses, several of which are highly pathogenic in other mammals, but cause no disease in bats. How this symbiotic relationship between bats and viruses exists is not yet fully understood. Existing evidence supports a specific role for the innate immune system, in particular type I interferon (IFN) responses, a major component of antiviral immunity. Previous studies in bats have shown that components of the IFN pathway are constitutively activated at the transcriptional level. In this study, we tested the hypothesis that the type I IFN response in bats is also constitutively activated at the protein level. For this, we utilized highly sensitive Single Molecule (Simoa) digital ELISA assays, previously developed for humans that we adapted to bat samples. We prospectively sampled four non-native chiroptera species from French zoos. We identified a constitutive expression of IFNα protein in the circulation of healthy bats, and concentrations that are physiologically active in humans. Expression levels differed according to the species examined, but were not associated with age, sex, or health status suggesting constitutive IFNα protein expression independent of disease. These results confirm a unique IFN response in bat species that may explain their ability to coexist with multiple viruses in the absence of pathology. These results may help to manage potential zoonotic viral reservoirs and potentially identify new anti-viral strategies.


Sujet(s)
Chiroptera/sang , Immunité innée , Interféron alpha/sang , Virus/immunologie , Animaux , Lignée cellulaire , Chiroptera/génétique , Chiroptera/immunologie , Chiroptera/virologie , Test ELISA , Régulation de l'expression des gènes , Interactions hôte-pathogène , Interféron alpha/génétique , Spécificité d'espèce , Symbiose , Transcription génétique , Virus/pathogénicité
6.
Nat Commun ; 12(1): 972, 2021 02 09.
Article de Anglais | MEDLINE | ID: mdl-33563978

RÉSUMÉ

Among the many questions unanswered for the COVID-19 pandemic are the origin of SARS-CoV-2 and the potential role of intermediate animal host(s) in the early animal-to-human transmission. The discovery of RaTG13 bat coronavirus in China suggested a high probability of a bat origin. Here we report molecular and serological evidence of SARS-CoV-2 related coronaviruses (SC2r-CoVs) actively circulating in bats in Southeast Asia. Whole genome sequences were obtained from five independent bats (Rhinolophus acuminatus) in a Thai cave yielding a single isolate (named RacCS203) which is most related to the RmYN02 isolate found in Rhinolophus malayanus in Yunnan, China. SARS-CoV-2 neutralizing antibodies were also detected in bats of the same colony and in a pangolin at a wildlife checkpoint in Southern Thailand. Antisera raised against the receptor binding domain (RBD) of RmYN02 was able to cross-neutralize SARS-CoV-2 despite the fact that the RBD of RacCS203 or RmYN02 failed to bind ACE2. Although the origin of the virus remains unresolved, our study extended the geographic distribution of genetically diverse SC2r-CoVs from Japan and China to Thailand over a 4800-km range. Cross-border surveillance is urgently needed to find the immediate progenitor virus of SARS-CoV-2.


Sujet(s)
Chiroptera/virologie , Pangolins/virologie , SARS-CoV-2/physiologie , Séquence d'acides aminés , Animaux , Anticorps neutralisants/sang , Asie du Sud-Est , COVID-19/virologie , Chiroptera/sang , Géographie , Tests de neutralisation , Phylogenèse , Domaines protéiques , Récepteurs de surface cellulaire/composition chimique , Récepteurs de surface cellulaire/métabolisme
7.
J Wildl Dis ; 57(1): 242-245, 2021 01 06.
Article de Anglais | MEDLINE | ID: mdl-33635999

RÉSUMÉ

We determined venous blood gas, acid-base, and biochemical parameters for thirteen free-ranging Indian flying foxes (Pteropus giganteus) in Myanmar, using a handheld i-STAT analyzer with CG8+ and CHEM8 cartridges. For field-based projects, portable blood analyzers enable identification and management of electrolyte and acid-base imbalances and collection of physiologic data, but present logistical challenges.


Sujet(s)
Analyse chimique du sang/médecine vétérinaire , Gazométrie sanguine/médecine vétérinaire , Chiroptera/sang , Animaux , Analyse chimique du sang/instrumentation , Gazométrie sanguine/instrumentation , Tests hématologiques/médecine vétérinaire , Myanmar , Systèmes automatisés lit malade
8.
Curr Biol ; 31(2): 257-270.e5, 2021 01 25.
Article de Anglais | MEDLINE | ID: mdl-33157026

RÉSUMÉ

Marburg virus (MARV) is among the most virulent pathogens of primates, including humans. Contributors to severe MARV disease include immune response suppression and inflammatory gene dysregulation ("cytokine storm"), leading to systemic damage and often death. Conversely, MARV causes little to no clinical disease in its reservoir host, the Egyptian rousette bat (ERB). Previous genomic and in vitro data suggest that a tolerant ERB immune response may underlie MARV avirulence, but no significant examination of this response in vivo yet exists. Here, using colony-bred ERBs inoculated with a bat isolate of MARV, we use species-specific antibodies and an immune gene probe array (NanoString) to temporally characterize the transcriptional host response at sites of MARV replication relevant to primate pathogenesis and immunity, including CD14+ monocytes/macrophages, critical immune response mediators, primary MARV targets, and skin at the inoculation site, where highest viral loads and initial engagement of antiviral defenses are expected. Our analysis shows that ERBs upregulate canonical antiviral genes typical of mammalian systems, such as ISG15, IFIT1, and OAS3, yet demonstrate a remarkable lack of significant induction of proinflammatory genes classically implicated in primate filoviral pathogenesis, including CCL8, FAS, and IL6. Together, these findings offer the first in vivo functional evidence for disease tolerance as an immunological mechanism by which the bat reservoir asymptomatically hosts MARV. More broadly, these data highlight factors determining disparate outcomes between reservoir and spillover hosts and defensive strategies likely utilized by bat hosts of other emerging pathogens, knowledge that may guide development of effective antiviral therapies.


Sujet(s)
Chiroptera/immunologie , Réservoirs de maladies/virologie , Tolérance immunitaire/immunologie , Maladie de Marbourg/immunologie , Marburgvirus/immunologie , Animaux , Infections asymptomatiques , Chiroptera/sang , Chiroptera/génétique , Chiroptera/virologie , Femelle , Régulation de l'expression des gènes/immunologie , Interactions hôte-pathogène/génétique , Interactions hôte-pathogène/immunologie , Humains , Tolérance immunitaire/génétique , Mâle , Maladie de Marbourg/virologie , Monocytes/immunologie
9.
Prev Vet Med ; 184: 105159, 2020 Nov.
Article de Anglais | MEDLINE | ID: mdl-33038611

RÉSUMÉ

Several species of trypanosomes can infect bats (Chiroptera), but current information about bat trypanosomes in Colombia is scarce. The objectives of this study were to estimate the infection rate and to characterize the trypanosome species infecting bats from three rural regions near the municipality of Cumaribo in Vichada, Colombia. Blood samples were collected from 39 bats. DNA was extracted from the blood samples and analyzed using nuclear genetic markers (SSU rDNA, ITS rDNA, and cathepsin genes) to discriminate among trypanosome species. Trypanosomes were detected in 66.7 % (26/39) of blood samples using PCR; 61.5 % (24/39) of infections were identified as Trypanosoma theileri and 5.1 % (2/39) as T. wauwau-like parasites. The phylogeographic analysis revealed that our T. theileri sequences were associated with the TthIIB genotype from cattle in Brazil and Venezuela. The T. wauwau-like parasites represent a new genotype of the species and were found in Molossus molossus and Platyrrhinus helleri bats. These data represent the first evidence of this trypanosome in both Colombia, and in these species of bats. Bat infections with T. theileri suggest an important role of these hosts in maintaining this genotype, probably acquired by ingesting insect vectors. The T. wauwau-like genotype in new mammalian host species supports the 'bat seeding' hypothesis of the T. cruzi clade. The epidemiological and evolutionary implications of these findings are discussed.


Sujet(s)
Chiroptera , Surveillance épidémiologique/médecine vétérinaire , Interactions hôte-parasite , Trypanosoma/isolement et purification , Trypanosomiase/médecine vétérinaire , Animaux , Chiroptera/sang , Colombie/épidémiologie , ADN des protozoaires/analyse , ADN ribosomique/analyse , Génotype , Prévalence , Trypanosoma/génétique , Trypanosomiase/sang , Trypanosomiase/épidémiologie , Trypanosomiase/parasitologie
10.
BMC Vet Res ; 16(1): 232, 2020 Jul 06.
Article de Anglais | MEDLINE | ID: mdl-32631329

RÉSUMÉ

BACKGROUND: Emergence of both viral zoonoses from bats and diseases that threaten bat populations has highlighted the necessity for greater insights into the functioning of the bat immune system. Particularly when considering hibernating temperate bat species, it is important to understand the seasonal dynamics associated with immune response. Body temperature is one of the factors that modulates immune functions and defence mechanisms against pathogenic agents in vertebrates. To better understand innate immunity mediated by phagocytes in bats, we measured respiratory burst and haematology and blood chemistry parameters in heterothermic greater mouse-eared bats (Myotis myotis) and noctules (Nyctalus noctula) and homeothermic laboratory mice (Mus musculus). RESULTS: Bats displayed similar electrolyte levels and time-related parameters of phagocyte activity, but differed in blood profile parameters related to metabolism and red blood cell count. Greater mouse-eared bats differed from mice in all phagocyte activity parameters and had the lowest phagocytic activity overall, while noctules had the same quantitative phagocytic values as mice. Homeothermic mice were clustered separately in a high phagocyte activity group, while both heterothermic bat species were mixed in two lower phagocyte activity clusters. Stepwise regression identified glucose, white blood cell count, haemoglobin, total dissolved carbon dioxide and chloride variables as the best predictors of phagocyte activity. White blood cell counts, representing phagocyte numbers available for respiratory burst, were the best predictors of both time-related and quantitative parameters of phagocyte activity. Haemoglobin, as a proxy variable for oxygen available for uptake by phagocytes, was important for the onset of phagocytosis. CONCLUSIONS: Our comparative data indicate that phagocyte activity reflects the physiological state and blood metabolic and cellular characteristics of homeothermic and heterothermic mammals. However, further studies elucidating trade-offs between immune defence, seasonal lifestyle physiology, hibernation behaviour, roosting ecology and geographic patterns of immunity of heterothermic bat species will be necessary. An improved understanding of bat immune responses will have positive ramifications for wildlife and conservation medicine.


Sujet(s)
Température du corps , Chiroptera/immunologie , Phagocytes/immunologie , Animaux , Comportement animal/physiologie , Analyse chimique du sang , Chiroptera/sang , Numération des érythrocytes
11.
PLoS One ; 15(7): e0234784, 2020.
Article de Anglais | MEDLINE | ID: mdl-32634149

RÉSUMÉ

The greater mouse-eared bat (Myotis myotis) is a flagship species for the protection of hibernation and summer maternity roosts in the Western Palearctic region. A range of pathogenic agents is known to put pressure on populations, including the white-nose syndrome fungus, for which the species shows the highest prevalence and infection intensity of all European bat species. Here, we perform analysis of blood parameters characteristic for the species during its natural annual life cycle in order to establish reference values. Despite sexual dimorphism and some univariate differences, the overall multivariate pattern suggests low seasonal variation with homeostatic mechanisms effectively regulating haematology and blood biochemistry ranges. Overall, the species displayed a high haematocrit and haemoglobin content and high concentration of urea, while blood glucose levels in swarming and hibernating bats ranged from hypo- to normoglycaemic. Unlike blood pH, concentrations of electrolytes were wide ranging. To conclude, baseline data for blood physiology are a useful tool for providing suitable medical care in rescue centres, for studying population health in bats adapting to environmental change, and for understanding bat responses to stressors of conservation and/or zoonotic importance.


Sujet(s)
Chiroptera/sang , Chiroptera/physiologie , Tests hématologiques/normes , Animaux , Régions arctiques/épidémiologie , Climat , Hématocrite/normes , Hibernation , Valeurs de référence , Saisons , Espèces sentinelles/physiologie
12.
PLoS One ; 15(5): e0232339, 2020.
Article de Anglais | MEDLINE | ID: mdl-32374743

RÉSUMÉ

Habitat-mediated global change is driving shifts in species' distributions which can alter the spatial risks associated with emerging zoonotic pathogens. Many emerging infectious pathogens are transmitted by highly mobile species, including bats, which can act as spill-over hosts for pathogenic viruses. Over three years, we investigated the seroepidemiology of paramyxoviruses and Australian bat lyssavirus in a range-expanding fruit bat, the Grey-headed flying fox (Pteropus poliocephalus), in a new camp in Adelaide, South Australia. Over six, biannual, sampling sessions, we quantified median florescent intensity (MFI) antibody levels for four viruses for a total of 297 individual bats using a multiplex Luminex binding assay. Where appropriate, florescence thresholds were determined using finite mixture modelling to classify bats' serological status. Overall, apparent seroprevalence of antibodies directed at Hendra, Cedar and Tioman virus antigens was 43.2%, 26.6% and 95.7%, respectively. We used hurdle models to explore correlates of seropositivity and antibody levels when seropositive. Increased body condition was significantly associated with Hendra seropositivity (Odds ratio = 3.67; p = 0.002) and Hendra virus levels were significantly higher in pregnant females (p = 0.002). While most bats were seropositive for Tioman virus, antibody levels for this virus were significantly higher in adults (p < 0.001). Unexpectedly, all sera were negative for Australian bat lyssavirus. Temporal variation in antibody levels suggests that antibodies to Hendra virus and Tioman virus may wax and wane on a seasonal basis. These findings suggest a common exposure to Hendra virus and other paramyxoviruses in this flying fox camp in South Australia.


Sujet(s)
Chiroptera/virologie , Virus Hendra/isolement et purification , Lyssavirus/isolement et purification , Animaux , Chiroptera/sang , Chiroptera/immunologie , Chiroptera/physiologie , Femelle , Virus Hendra/immunologie , Lyssavirus/immunologie , Mâle , Reproduction , Études séroépidémiologiques
13.
Mol Ecol ; 29(9): 1745-1755, 2020 05.
Article de Anglais | MEDLINE | ID: mdl-32279365

RÉSUMÉ

Emerging fungal diseases have become challenges for wildlife health and conservation. North American hibernating bat species are threatened by the psychrophilic fungus Pseudogymnoascus destructans (Pd) causing the disease called white-nose syndrome (WNS) with unprecedented mortality rates. The fungus is widespread in North America and Europe, however, disease is not manifested in European bats. Differences in epidemiology and pathology indicate an evolution of resistance or tolerance mechanisms towards Pd in European bats. We compared the proteomic profile of blood plasma in healthy and Pd-colonized European Myotis myotis and North American Myotis lucifugus in order to identify pathophysiological changes associated with Pd colonization, which might also explain the differences in bat survival. Expression analyses of plasma proteins revealed differences in healthy and Pd-colonized M. lucifugus, but not in M. myotis. We identified differentially expressed proteins for acute phase response, constitutive and adaptive immunity, oxidative stress defence, metabolism and structural proteins of exosomes and desmosomes, suggesting a systemic response against Pd in North American M. lucifugus but not European M. myotis. The differences in plasma proteomic profiles between European and North American bat species colonized by Pd suggest European bats have evolved tolerance mechanisms towards Pd infection.


Sujet(s)
Ascomycota/pathogénicité , Chiroptera/sang , Chiroptera/microbiologie , Évolution moléculaire , Animaux , Chiroptera/classification , Europe , Hibernation , Amérique du Nord , Plasma sanguin , Protéomique
14.
J Am Assoc Lab Anim Sci ; 59(3): 275-281, 2020 05 01.
Article de Anglais | MEDLINE | ID: mdl-32164795

RÉSUMÉ

Jamaican fruit bats (Artibeus jamaicensis) are used as an animal model for several viruses, including Middle East respiratory syndrome virus, dengue virus, Zika virus, and Tacaribe virus. However, despite ongoing studies regarding these pathogens, little is known regarding the bats' normal physiology. In this study, phlebotomy of the propetagial (cephalic) vein was performed to establish baseline hematologic parameters in an apparently healthy, captive population of Jamaican fruit bats. Furthermore, we compared results from physically restrained and isoflurane-anesthetized bats. Our findings indicate significant increases in WBC count, lymphocytes, and monocytes in the anesthetized bats. However, RBC and platelet parameters were not different between the 2 groups. This information on the normal hematologic parameters of Jamaican fruit bats, adds to our overall understanding of the normal physiology of this species, and expands our knowledge on bat species in general.


Sujet(s)
Chiroptera/physiologie , Tests hématologiques/médecine vétérinaire , Anesthésiques par inhalation/administration et posologie , Animaux , Chiroptera/sang , Chiroptera/classification , Femelle , Isoflurane/administration et posologie , Numération des leucocytes/médecine vétérinaire , Mâle , Valeurs de référence , Contention physique/médecine vétérinaire , Zoonoses virales
15.
J Infect Dis ; 221(Suppl 4): S375-S382, 2020 05 11.
Article de Anglais | MEDLINE | ID: mdl-32034942

RÉSUMÉ

Bat-borne zoonotic pathogens belonging to the family Paramxyoviridae, including Nipah and Hendra viruses, and the family Filoviridae, including Ebola and Marburg viruses, can cause severe disease and high mortality rates on spillover into human populations. Surveillance efforts for henipaviruses and filoviruses have been largely restricted to the Old World; however, recent studies suggest a potentially broader distribution for henipaviruses and filoviruses than previously recognized. In the current study, we screened for henipaviruses and filoviruses in New World bats collected across 4 locations in Trinidad near the coast of Venezuela. Bat tissue samples were screened using previously established reverse-transcription polymerase chain reaction assays. Serum were screened using a multiplex immunoassay to detect antibodies reactive with the envelope glycoprotein of viruses in the genus Henipavirus and the family Filoviridae. Serum samples were also screened by means of enzyme-linked immunosorbent assay for antibodies reactive with Nipah G and F glycoproteins. Of 84 serum samples, 28 were reactive with ≥1 henipavirus glycoprotein by ≥1 serological method, and 6 serum samples were reactive against ≥1 filovirus glycoproteins. These data provide evidence of potential circulation of viruses related to the henipaviruses and filoviruses in New World bats.


Sujet(s)
Chiroptera/virologie , Infections à Filoviridae/médecine vétérinaire , Filoviridae , Infections à hénipavirus/médecine vétérinaire , Henipavirus , Animaux , Chiroptera/sang , Chiroptera/classification , Infections à Filoviridae/épidémiologie , Infections à Filoviridae/virologie , Infections à hénipavirus/épidémiologie , Infections à hénipavirus/virologie , Tests sérologiques , Trinité-et-Tobago/épidémiologie
16.
J Virol ; 94(7)2020 03 17.
Article de Anglais | MEDLINE | ID: mdl-31941778

RÉSUMÉ

Southern China is a hot spot of emerging infectious diseases, in which diverse species of bats dwell, a large group of flying mammals considered natural reservoirs for zoonotic viruses. Recently, divergent filoviruses (FiVs) have been identified in bats within this region, which pose a potential risk to public health, but the true infection situation in bats remains largely unclear. Here, 689 archived bat serum samples were analyzed by enzyme-linked immunosorbent assay (ELISA), Western blotting, and neutralization assay to investigate the seroprevalence and cross-reactivity of four divergent FiVs and two other viruses (rabies virus and Tuhoko pararubulavirus 1) of different families within the order Mononegavirales Results showed no cross-antigenicity between FiVs and other mononegaviruses but different cross-reactivity among the FiVs themselves. The total FiV seroreactive rate was 36.3% (250/689), with infection by the indigenous Chinese FiV DH04 or an antigenically related one being the most widely and the most highly prevalent. Further viral metagenomic analysis of fruit bat tissues also identified the gene sequence of a novel FiV. These results indicate the likely prevalence of other so far unidentified FiVs within the Chinese bat population, with frugivorous Rousettus leschenaultii and Eonycteris spelaea bats and insectivorous Myotis horsfieldii and Miniopterus schreibersii bats being their major reservoirs.IMPORTANCE Bats are natural hosts of many FiVs, from which diverse FiVs were serologically or virologically detected in Africa, Europe, and East Asia. Recently, very divergent FiVs were identified in the Chinese bat population, but their antigenic relationship with other known FiVs remains unknown. Here, we conducted serological characterization and investigation of Chinese indigenous FiVs and prototypes of other viruses in bats. Results indicated that Chinese indigenous FiVs are antigenically distant to other FiVs, and infection of novel or multiple FiVs occurred in Chinese bats, with FiV DH04 or an antigenically related one being the most widely and the most highly prevalent. Additionally, besides Rousettus leschenaultii and Eonycteris spelaea bats, the insectivorous Myotis horsfieldii and M. schreibersii bats are highly preferential hosts of FiVs. Seroreactive and viral metagenomic results indicated that more as yet unknown bat-borne FiVs circulate in Southern China, and to uncover them further, investigation and timely surveillance is needed.


Sujet(s)
Anticorps antiviraux/sang , Chiroptera/virologie , Infections à Filoviridae/médecine vétérinaire , Filoviridae/immunologie , Animaux , Chine , Chiroptera/sang , Co-infection , Réservoirs de maladies/médecine vétérinaire , Réservoirs de maladies/virologie , Test ELISA , Filoviridae/classification , Métagénomique , Tests de neutralisation , Paramyxoviridae , Infections à Paramyxoviridae/sang , Infections à Paramyxoviridae/médecine vétérinaire , Phylogenèse , Rhabdoviridae , Infections à Rhabdoviridae/sang , Infections à Rhabdoviridae/médecine vétérinaire , Études séroépidémiologiques
17.
Braz. J. Vet. Res. Anim. Sci. (Online) ; 57(3): e168582, 2020. mapas, tab, graf
Article de Anglais | VETINDEX, LILACS | ID: biblio-1122183

RÉSUMÉ

It was provide a hematological profile of Artibeus lituratus (Phyllostomidae: Stenodermatinae). Animals were collected from October 2017 to February 2018 in an urban forest in the city of Rio de Janeiro, Southeastern Brazil. Males and females showed similar overall mean values for the parameters analyzed. Males had higher values for erythrocytes (RBC), hematocrit and basophils. Females had higher levels of eosinophils than males. The hematological values reported here will serve as reference for future research on health conditions of free-living and captive populations of Artibeus lituratus, as well as for research on pathogens associated with these bats.(AU)


O presente trabalho estabeleceu o perfil hematológico de morcegos frugívoros de vida livre, A. lituratus (Phyllostomidae: Stenodermatinae). As amostragens foram realizadas de outubro de 2017 a fevereiro de 2018 em uma floresta urbana na cidade do Rio de Janeiro, Sudeste do Brasil. Machos e fêmeas apresentaram valores médios gerais semelhantes para os parâmetros analisados. Os machos apresentaram valores de eritrócitos (RBC), hematócrito e basófilos mais altos. As fêmeas apresentaram níveis mais elevados de eosinófilos que os machos. Os valores hematológicos aqui reportados servirão de referência para pesquisas sobre condições de saúde de populações de Artibeus lituratus em vida livre e de cativeiro, assim como para pesquisas sobre patógenos associados a esses morcegos.(AU)


Sujet(s)
Animaux , Chiroptera/sang , Granulocytes éosinophiles , Érythrocytes , Hématocrite , Tests hématologiques/médecine vétérinaire
18.
PLoS Negl Trop Dis ; 13(10): e0007733, 2019 10.
Article de Anglais | MEDLINE | ID: mdl-31671094

RÉSUMÉ

Bats are reservoirs for several zoonotic pathogens, including filoviruses. Recent work highlights the diversity of bat borne filoviruses in Asia. High risk activities at the bat-human interface pose the threat of zoonotic virus transmission. We present evidence for prior exposure of bat harvesters and two resident fruit bat species to filovirus surface glycoproteins by screening sera in a multiplexed serological assay. Antibodies reactive to two antigenically distinct filoviruses were detected in human sera and to three individual filoviruses in bats in remote Northeast India. Sera obtained from Eonycteris spelaea bats showed similar patterns of cross-reactivity as human samples, suggesting them as the species responsible for the spillover. In contrast, sera from Rousettus leschenaultii bats reacted to two different virus glycoproteins. Our results indicate circulation of several filoviruses in bats and the possibility for filovirus transmission from bats to humans.


Sujet(s)
Anticorps antiviraux/sang , Chiroptera/immunologie , Chiroptera/virologie , Réservoirs de maladies/virologie , Infections à Filoviridae/épidémiologie , Infections à Filoviridae/médecine vétérinaire , Filoviridae/immunologie , Adolescent , Adulte , Animaux , Chiroptera/sang , Ebolavirus/immunologie , Filoviridae/classification , Filoviridae/isolement et purification , Infections à Filoviridae/immunologie , Infections à Filoviridae/virologie , Cartographie géographique , Glycoprotéines/immunologie , Humains , Inde/épidémiologie , Glycoprotéines membranaires , Adulte d'âge moyen , Phylogenèse , Études séroépidémiologiques , Jeune adulte
19.
Article de Anglais | MEDLINE | ID: mdl-31400499

RÉSUMÉ

Hematological measures are increasingly being used to analyse the impact of several stressors on the physiological condition of animals. Landscape degradation and habitat loss impacts terrestrial and volant mammals occurrence, however rarely the effects of these factors on physiological conditions and stress levels were analyzed. Here, we measured several hematological parameters to analyse the impacts of habitat amount on the physiological condition (body condition and health status) and stress level of four species of Neotropical fruit-eating bats. We measured hematocrit, hemoglobin concentration and calculated the hemoglobin-hematocrit residuals (HHR) and mean cell hemoglobin concentration (MCHC), as well as the neutrophil to lymphocyte ratio (N/L ratio) of four common frugivores bat species (Artibeus lituratus, Artibeus planirostris, Sturnira lilium and Carollia perspicilatta). The bats were captured in 20 landscapes within the Atlantic Forest biodiversity hotspot, in a gradient from 10 to 85% of habitat amount. We tested the influence of habitat amount, species, sex and reproductive condition on the physiological variables. We fit GLM to each of the response variables and performed a model selection to identify the most plausible to explain the patterns. N/L ratio was negatively influenced by habitat amount, while the other variables were not related to habitat amount. Overall, we found that habitat loss apparently did not jeopardize the physiological condition of fruit-eating bats and that stress level apparently is not high enough to have any deleterious effect. We suggest that the increase in glucocorticoids, indirectly assessed by the N/L ratio, is a predictive, beneficial response, that allow these bats to cope efficiently with the stressors associated with habitat loss.


Sujet(s)
Biodiversité , Chiroptera/physiologie , Conservation des ressources naturelles , Animaux , Chiroptera/sang , Écosystème , Fruit/composition chimique , Système génital/physiologie , Lymphocytes/physiologie , Granulocytes neutrophiles/physiologie
20.
Physiol Biochem Zool ; 92(4): 386-395, 2019.
Article de Anglais | MEDLINE | ID: mdl-31141467

RÉSUMÉ

As small, flying, mammalian endotherms, insectivorous bats are adapted to operate at high levels of energy expenditure. In response to seasonally variable challenges, we predicted that bats should balance energy budgets by flexibly adjusting aspects of their physiology or behavior in ways that elevate metabolic capacity. We examined variation in energy storage and pathways for oxidative metabolism in Brazilian free-tailed bats (Tadarida brasiliensis) related to estimated costs associated with reproduction and migration. We collected pectoral muscle and liver from female T. brasiliensis at six time points during the summer and fall and measured changes in the activity of four enzymes involved with lipid metabolism. Body mass varied substantially with life-cycle stage, suggesting that rapid accumulation and use of fat stores occurs in response to current and anticipated energy demands. Catabolic enzyme activity (carnitine palmitoyl transferase [CPT], 3-hydroxyacyl-CoA dehydrogenase [HOAD], and citrate synthase [CS]) in the muscle was increased during lactation compared with early pregnancy but exhibited no change before fall migration. While there was no temporal change in lipid biosynthetic capacity in the liver, fatty acid synthase activity was negatively correlated with body mass. Variation in body mass and enzyme activity in T. brasiliensis during the summer suggests that stored energy is mobilized and lipid oxidative capacity is increased during periods of increased demand and that lipid biosynthetic capacity is increased with depletion of fat stores. These results suggest that bats are able to flexibly adjust metabolic capacity based on energy requirement to maintain energy balance despite high levels of expenditure.


Sujet(s)
Chiroptera/sang , Chiroptera/métabolisme , Métabolisme énergétique , Métabolisme lipidique , Saisons , Animaux , Femelle
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