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1.
Spleen is one of the important lymphoid organs with wide variations of morphological and physiological functions according to species. Morphology and function of the spleen in bats, which are hosts to several viral strains without exhibiting clinical symptoms, remain to be fully elucidated. This study aims to examine the spleen morphology of fruit bats associated with their physiological functions. Spleen histological observations were performed in three fruit bats species: Cynopterus titthaecheilus (n = 9), Rousettus leschenaultii (n = 3) and Pteropus vampyrus (n = 3). The spleens of these fruit bats were surrounded by a thin capsule. Red pulp consisted of splenic cord and wide vascular space filled with blood. Ellipsoids in all three studied species were found numerously and adjacent to one another forming macrophages aggregates. White pulp consisted of periarteriolar lymphoid sheaths (PALS), lymphoid follicles and marginal zone. The lymphoid follicle contained a germinal centre and a tingible body macrophage that might reflect an active immune system. The marginal zone was prominent and well developed. This study reports some differences in spleen structure of fruit bats compared to other bat species previously reported and discusses possible physiological implications of the spleen based on its morphology.  相似文献   

2.
The distribution and composition of extracellular matrix (ECM) of the spleen in two species of fruit bats, namely Cynopterus titthaecheilus and Rousettus leschenaultii, were examined by histochemistry and immunohistochemistry. Reticular fibres accompanied by laminin were identified to make up the splenic stromal network. Types I and III collagen were identified in various spleen compartments with varying intensities. Thin and short elastin fibres were scattered in several parts of the spleen. Visualization of the ECM of the spleen can better demonstrate spleen compartmentalization. The alleged vascular space structure in the fruit bats spleen was the sinus structure that was strengthened by the presence of reticular fibres that limit the sinus basement membrane. The present study identified periellipsoidal lymphoid sheath (PELS)-like structure in fruit bats spleen that had never been identified in mammals before. In addition to describing the structure, this study highlighted the variations in ECM composition of the spleen between species that can provide new insight into the phylogenetic study of spleen morphology.  相似文献   

3.
Species in the bacterial genus, Bartonella, can cause disease in both humans and animals. Previous reports of Bartonella in bats and ectoparasitic bat flies suggest that bats could serve as mammalian hosts and bat flies as arthropod vectors. We compared the prevalence and genetic similarity of bartonellae in individual Costa Rican bats and their bat flies using molecular and sequencing methods targeting the citrate synthase gene (gltA). Bartonellae were more prevalent in bat flies than in bats, and genetic variants were sometimes, but not always, shared between bats and their bat flies. The detected bartonellae genetic variants were diverse, and some were similar to species known to cause disease in humans and other mammals. The high prevalence and sharing of bartonellae in bat flies and bats support a role for bat flies as a potential vector for Bartonella, while the genetic diversity and similarity to known species suggest that bartonellae could spill over into humans and animals sharing the landscape.  相似文献   

4.
Molecular analyses of blood samples revealed infection with hemoplasmas in 97% of 31 cave bats captured in three caves in North-Eastern Spain. The characterization of 1250 bp of the 16S rRNA gene in 29 of the positive bats identified two different groups of sequences. Twenty-two Schreibers’ bats (Miniopterus schreibersii) and one long-eared bat (Myotis capaccinii) shared one group, composed of seven closely related sequences. These sequences showed an identity of about 97% with “Candidatus Mycoplasma hemohominis” and the phylogenetic branch including bat and human sequences showed a 100% bootstrap value, supporting a close phylogenetic relationship between these hemoplasmas. The second group, representing a potentially novel species, was composed of a single sequence shared by six Schreibers’ bats that had 91% identity with the recently reported hemoplasma from little brown bats in North America. Large bat aggregations in roosting caves probably benefits intra and inter-species transmission explaining the high observed prevalence.  相似文献   

5.
Bats represent the largest dietary radiation in a single mammalian order, and have become an emerging model group for studying dietary evolution. Taste receptor genes have proven to be molecular signatures of dietary diversification in bats. For example, all 3 extant species of vampire bats have lost many bitter taste receptor genes (Tas2rs) in association with their dietary shift from insectivory to sanguivory. Indeed, only 8 full-length Tas2rs were identified from the high-quality genome of the common vampire bat (Desmodus rotundus). However, it is presently unknown whether these bitter receptors are functional, since the sense of taste is less important in vampire bats, which have an extremely narrow diet and rely on other senses for acquiring food. Here, we applied a molecular evolutionary analysis of Tas2rs in the common vampire bat compared with non-vampire bats. Furthermore, we provided the first attempt to deorphanize all bitter receptors of the vampire bat using a cell-based assay. We found that all Tas2r genes in the vampire bat have a level of selective pressure similar to that in non-vampire bats, suggesting that this species must have retained some bitter taste functions. We demonstrated that 5 of the 8 bitter receptors in the vampire bat can be activated by some bitter compounds, and observed that the vampire bat generally can not detect naturally occurring bitter compounds examined in this study. Our study demonstrates functional retention of bitter taste in vampire bats as suggested by cell-based functional assays, calling for an in-depth study of extra-oral functions of bitter taste receptors.  相似文献   

6.
Bats have been demonstrated to be natural reservoirs of severe acute respiratory syndrome coronavirus (SARS CoV) and Middle East respiratory syndrome (MERS) CoV. Faecal samples from 248 individuals of 20 bat species were tested for partial RNA‐dependent RNA polymerase gene of CoV and 57 faecal samples from eight bat species were tested positive. The highest detection rate of 44% for Scotophilus kuhlii, followed by 30% for Rhinolophus monoceros. Significantly higher detection rates of coronaviral RNA were found in female bats and Scotophilus kuhlii roosting in palm trees. Phylogenetic analysis classified the positive samples into SARS‐related (SARSr) CoV, Scotophilus bat CoV 512 close to those from China and Philippines, and Miniopterus bat CoV 1A‐related lineages. Coronaviral RNA was also detected in bat guano from Scotophilus kuhlii and Myotis formosus flavus on the ground and had potential risk for human exposure. Diverse bat CoV with zoonotic potential could be introduced by migratory bats and maintained in the endemic bat population in Taiwan.  相似文献   

7.
The vertebral heart score (VHS) measurement is commonly used to provide a more objective measurement of cardiomegaly in canines. However, several studies have shown significant breed variations from the value previously established by Buchanan and Bücheler (9.7 ± 0.5). This study describes VHS measurements in Pug, Pomeranian, Yorkshire Terrier, Dachshund, Bulldog, Shih Tzu, Lhasa Apso, and Boston Terrier dog breeds. Dogs with two or three view thoracic radiographs, no subjective radiographic evidence of cardiomegaly, and no physical examination findings of heart murmurs or gallop rhythms were included in the study. The Pug, Pomeranian, Bulldog, and Boston Terrier groups were found to have a VHS significantly greater than 9.7 ± 0.5 (P < 0.00001, P = 0.0014, P < 0.0001, P < 0.00001, respectively). Body condition score (BCS) was found to have a significant effect on the VHS of Lhasa Apso group. Anomalous vertebrae in the thoracic column were associated with a significant increase in VHS of the Bulldog (P = 0.028) and Boston Terrier (P = 0.0004) groups. Thoracic depth to width ratio did not have a significant effect on VHS.  相似文献   

8.
Bats are hosts of diverse coronaviruses (CoVs) known to potentially cross the host–species barrier. For analysing coronavirus diversity in a bat species‐rich country, a total of 421 anal swabs/faecal samples from Costa Rican bats were screened for CoV RNA‐dependent RNA polymerase (RdRp) gene sequences by a pancoronavirus PCR. Six families, 24 genera and 41 species of bats were analysed. The detection rate for CoV was 1%. Individuals (n = 4) from four different species of frugivorous (Artibeus jamaicensis, Carollia perspicillata and Carollia castanea) and nectivorous (Glossophaga soricina) bats were positive for coronavirus‐derived nucleic acids. Analysis of 440 nt. RdRp sequences allocated all Costa Rican bat CoVs to the α‐CoV group. Several CoVs sequences clustered near previously described CoVs from the same species of bat, but were phylogenetically distant from the human CoV sequences identified to date, suggesting no recent spillover events. The Glossophaga soricina CoV sequence is sufficiently dissimilar (26% homology to the closest known bat CoVs) to represent a unique coronavirus not clustering near other CoVs found in the same bat species so far, implying an even higher CoV diversity than previously suspected.  相似文献   

9.
《African Zoology》2013,48(1):109-113
Tadarida aegyptiaca (mean body mass 13.5 g) is a fast flying insectivorous bat that hunts in open areas for extended periods, covering extensive distances during its foraging bouts. Whole blood samples taken from the wing arteries were analysed for 2,3-diphosphoglyceric acid, oxygen affinity and pH. The mean oxygen affinity of T. aegyptiaca blood with a P50-value 38.3 mm Hg (5.1 kPa) is lower than that of similar-sized bats but not as low as the P50-values of 48.5 mm Hg (6.4 kPa) in two mice species. This indicates that oxygen affinity of the blood in T. aegyptiaca and other bats is designed to facilitate both effective binding of oxygen with haemoglobin at the alveolar/blood capillary interface and oxygen offloading in the tissues. Haematocrits (54–60 %) and levels of 2,3 DPG (2.36–3.30 mM l–1) were higher, and blood pH (7.106–7.229) lower, than those reported for terrestrial species of a similar size, but within the range of values reported for other bats. We conclude that adequate delivery of oxygen to tissues with high metabolic demands during flight is facilitated primarily by an elevated haematocrit and a reduced blood pH in response to elevated levels of metabolic by-products such as 2,3-DPG (from the citrate acid cycle) and CO2 (leading to increased concentrations of H+ ions).  相似文献   

10.
《African Zoology》2013,48(2):348-350
Frugivores feed on fruits and nectars that contain different types of sugars in different proportions, which provide these animals with energy. Wahlberg’s epauletted fruit bat (Epomophorus wahlbergi) has a high glucose intake irrespective of sugar concentration of nectar. It is not known how these bats regulate their blood plasma glucose concentrations in order to avoid the negative effects associated with hyperglycemia. Fruit bats have a high amount of sugar intake in a short period of time which could cause a glucose challenge and it is therefore necessary to determine whether these bats are able to regulate their blood plasma glucose concentrations within normal concentrations. This study investigated the diel variations in blood plasma glucose concentrations of E. wahlbergi. Epomophorus wahlbergi‘s blood plasma glucose concentration was lower (5.24 ± 0.38 mmol/l) at 18:00 before feeding and increased during/after feeding (8.19 ± 1.24 mmol/l) but bats appeared to regulate it within limits. Their range in concentrations was higher than the normal mammalian blood plasma glucose concentrations range. Consequently these bats appear to regulate their blood plasma glucose concentration, although at a range higher than normal mammalian levels, and thus reduce the negative consequences associated with hyperglycemia.  相似文献   

11.
Experimental infection of Artibeus intermedius, the great fruit-eating bat, was performed with vampire bat rabies isolates. Bats (n = 35) were captured in the wild and quarantined prior to experimental infection. No rabies antibodies were detected by rapid fluorescent focus inhibition test (RFFIT) prior to infection. Three doses of rabies virus (RV) and three different routes of infection were used. One out of 35 bats died without showing any clinical signs at day 14 and was positive for rabies. None of the 34 other bats showed clinical signs for rabies, but high antibody titers were detected post-inoculation, suggesting either innate immune response to the vampire bat rabies virus or possible pre-exposure to RV and inoculation leading to a booster effect. Rabies virus was detected by hemi-nested RT-PCR (hnRT-PCR) in the brain (n = 3), stomach (n = 1) of bats that were negative by immunofluorescence and that survived rabies infection. The bat that died on day 14 was positive by hnRT-PCR on the brain, heart and liver. These results suggest that either previous non-lethal exposure to RV or natural low susceptibility to vampire bat viruses somehow protected Artibeus intermedius from clinical rabies infection leading to a marginal lethality effect on this bats species population in the wild.  相似文献   

12.
Objectives To establish normal reference ranges of ocular parameters including phenol read thread, palpebral fissure length, horizontal and vertical corneal diameter, upright and hanging intraocular pressure (IOP) and to report ophthalmic examination findings of the anterior segment and lens, in a population of captive fruit bats. Animals studied Eyes of 30 bats of three species were included in this study: 10 (5 males, 5 females) Malayan Flying Foxes (Pteropus vampyrus), 10 (5 males, 5 females) Little Golden‐mantled Flying Foxes (Pteropus pumilus), and 10 (4 males, 6 females) Island Flying Foxes (Pteropus hypomelanus). Results The most common ophthalmic examination findings included iris‐iris persistent pupillary membranes (83%), nuclear sclerosis (56.7%), prominent arterial circle (40%), iridal hyperpigmented foci (30%), pupillary margin cysts (27%), and third eyelid defects (20%). The mean, among all species for: phenol red thread was 20.23 ± 1.28 mm/15 s both eyes (OU); palpebral fissure length was 13.34 ± 0.33 mm for OU; for horizontal corneal diameter was 10.72 ± 0.32 mm for OU; for vertical corneal diameter was 9.90 ± 0.30 mm for OU; for the hanging intraocular pressures was 19.38 ± 0.77 mmHg for OU; for upright IOP was 13.95 ± 0.60 mmHg for OU. Measurements for the individual species groups and eyes were also calculated. Conclusions Results revealed the IOP of bats in a hanging position were significantly higher than the IOP of bats in an upright position. The size of the bat, between the species, affected palpebral fissure length, horizontal corneal diameter, and vertical corneal diameter. Information about the ocular structures and normal ophthalmic parameters for the Pteropus species is crucial for species protection because of dependence on vision for survival.  相似文献   

13.
There is growing evidence that dilated cardiomyopathy may be a major cause of death in captive Livingstone's fruit bats (Pteropus livingstonii). Therefore, the primary aim of this prospective, exploratory study was to examine whether a systematic cardiac ultrasound protocol is feasible in this critically endangered species and to report basic measures of cardiac structure and function from a cohort of apparently healthy bats. A secondary aim was to test the effect posture (dorsal recumbency vs. roosting) has upon cardiac function in this species. Transthoracic echocardiograms, including 2D, Doppler, and tissue Doppler measures of cardiac structure and function were completed as part of routine health examinations for bats at a single center (n = 19). Bats were then grouped by age and disease status and the mean and range data reported for each group. In healthy adult bats, with the exception of a reduction in heart rate (P ≤ 0.05), right atrial systolic area (P ≤ 0.05), and right ventricular velocity during atrial contraction, there were no significant changes in cardiac structure or function in response to the roosting position. However, in the bats presenting with dilated cardiomyopathy the current data suggest that left ventricular ejection fraction is improved while roosting. Further work is required to confirm our initial findings, generate diagnostic reference intervals, and explore the causes of dilated cardiomyopathy in this species.  相似文献   

14.
Bats are an important reservoir of several zoonotic diseases. However, the circulation of bat coronaviruses (BatCoV) in live animal markets in Indonesia has not been reported. Genetic characterization of BatCoV was performed by sequencing partial RdRp genes. Real-time polymerase chain reaction based on nucleocapsid protein (N) gene and Enzyme-linked immunosorbent assay against the N protein were conducted to detect the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral RNA and antibody, respectively. We identified the presence of BatCoV on Cynopterus brachyotis, Macroglossus minimus, and Rousettus amplexicaudatus. The results showed that the BatCoV included in this study are from an unclassified coronavirus group. Notably, SARS-CoV-2 viral RNA and antibodies were not detected in the sampled bats.  相似文献   

15.
Bats have been implicated as reservoirs of relapsing fever group spirochaetes since the beginning of the last century. Recently, bat‐associated spirochaetes have been reported as human pathogens. In 1968, a spirochaete was detected in blood of the bat Natalus tumidirostris captured inside the Macaregua cave, Colombia. Data on this microorganism were never published again. The aim of this study was to evaluate the presence of Borrelia DNA in blood from bats of Macaregua cave. We performed molecular analyses using a genus‐specific real‐time PCR targeting the 16S rRNA to detect DNA of Borrelia in blood samples from 46 bats captured in the Macaregua cave. Positive samples were submitted to a battery of PCRs aiming to amply Borrelia 16S rRNA, flaB, glpQ, p66, ospC, clpA, clpX, nifS, pepX, pyrG, recG, rplB and uvrA genes. Seventeen samples were positive for Borrelia after real‐time PCR. With the exception of flaB gene, attempts to amplify further loci were unsuccessful. Nucleotide and amino acid divergences of four flaB haplotypes characterized from blood of Carollia perspicillata showed Borrelia burgdorferi sensu lato (Bbsl) as the most closely related group. A phylogenetic tree including 74 sequences of the genus confirmed this trend, since Borrelia genotypes detected in bats from Macaregua formed a monophyletic group basally positioned to Bbsl. Our results suggest that Borrelia genotypes characterized from bats roosting in the Macaregua cave might constitute a new taxon within the genus. This is the first molecular characterization of a Borrelia sp. in Colombia.  相似文献   

16.
We examined Bartonella prevalence in 281 bat flies collected from 114 eastern bent-wing bats (Miniopterus fuliginosus) in Japan and phylogenetically analyzed with other bat fly and bat strains. The bat flies were identified as Penicilidia jenynsii (PJ; n = 45), Nycteribia allotopa (NA; n = 157), and novel Nycteribia species (NS; n = 79). Bartonella DNAs were detected in 31.7 % (89/281) of bat flies by PCR targeting the citrate synthase (gltA) gene. The prevalence of Bartonella DNA among the bat flies was 47.1 % (74/157) in NA, 15.2 % (12/79) in NS, and 6.7 % (3/45) in PJ. Bartonella bacteria were also isolated from two NA and one NS. A phylogenetic analysis of the gltA sequences revealed that bat fly-associated strains were classified into three lineages and the same lineages of Bartonella were commonly detected from both Nycteribia bat flies and Miniopterus bats. These results suggest that Nycteribia bat flies are potential vectors for transmitting Bartonella among Miniopterus bats.  相似文献   

17.
The present study aimed to investigate the frequency of pathogenic Leptospira spp. in Brazilian bats and to determine possible risk factors associated to it. Ninety two bats of 12 species were evaluated. Whole genomic DNA from kidneys was extracted and real-time PCR specific to pathogenic Leptospira spp. was applied. Association between the frequency of specimens positive for Leptospira spp. and sex, age, bat species or family, season of collection, geographic localization and feeding habits was evaluated. The results showed that 39.13% of analyzed bats were found positive for Leptospira spp. Nine bat species had at least one positive result. There was no association among the evaluated variables and frequency of pathogenic Leptospira spp. Although the limitations due to lack of Leptospira spp. isolation, leptospiral carriage was demonstrated in bats of different species from southern Brazil, which reinforces the need for surveillance of infectious agents in wild animals.  相似文献   

18.
Introduction/objectivesIt has been proposed that vertebral left atrial size (VLAS) on thoracic radiographs can be used to assess the left atrial enlargement in dogs with myxomatous mitral valve disease (MMVD). However, it remains unclear whether VLAS can be used to distinguish dogs between pre-clinical MMVD that are at a greater risk of developing congestive heart failure (CHF) from those at a lower risk. We investigated this possibility.Animals, materials and methodsForty-one dogs with MMVD were retrospectively classified into one of two groups, a group that developed CHF (group CHF, n = 17) or remained CHF-free (group no-CHF, n = 24). The value of vertebral heart scale (VHS) and VLAS at three time-points, change in VHS and VLAS at a specific time interval (ΔVHS, ΔVLAS) and rate of change in the values per month (ΔVHS/month, ΔVLAS/month) were compared.ResultsAt the first visit, there were no significant differences in VLAS between the groups. At the median of 105 (interquartile ranges 83–155) days prior to the onset of CHF (group CHF) or the last visit (group no-CHF), VLAS was significantly higher in group CHF (mean, 2.9; standard deviation ± 0.4) than in group no-CHF (2.6 ± 0.3) (p = 0.028). ΔVLAS/month (area under the curve, 0.91; p<0.001) showed high diagnostic accuracy in distinguishing which dogs would develop CHF within 180 days and which would not.ConclusionsVLAS and ΔVLAS/month in dogs with pre-clinical MMVD may be useful to identify dogs at risk of developing CHF within the next 180 days.  相似文献   

19.
Australian bat lyssavirus (ABLV) is a member of the Lyssavirus genus of the Rhabdoviridae family and is found in Australian bat species. It is of public health concern because of the rabies-like syndrome it causes in humans, resulting in government health and wildlife agencies using varied communication approaches to inform targeted audiences about zoonotic risks associated with handling bats. Despite these warnings, the number of reports of human-bat interactions remains high. This paper details a survey conducted to analyse the approaches utilised by a range of stakeholders to educate and communicate warnings to their target audiences. The survey focused on identifying the target audiences, communication methods used, along with the message frequency, content, and perceived effectiveness. Analysis of the top three messages delivered by stakeholders revealed that over half were information-focused messages and over a third, instruction-focused. Stakeholders identified the need to balance messaging about bat handling risks with information regarding the vulnerable status of bats and their environmental significance. Whilst the most common and (perceived) effective method of communication was one-on-one discussions, it was also identified to be ineffective for targeting mass audiences leading stakeholders to recognise the need to adapt to more efficient means of communication. The outcomes of this study may be useful to improve risk communication strategies regarding ABLV in Australia.  相似文献   

20.
Bat rabies in alberta 1979-1982   总被引:2,自引:2,他引:0  
The infection rate among eight species of bats submitted for rabies diagnosis in Alberta during 1979-82 was 4.6%. Prevalence of rabies was greatest (24%) for hoary bats Lasiurus cinereus, while the big brown bat Eptesicus fuscus was the species in which rabies was most commonly diagnosed, and the species submitted most frequently for rabies diagnosis was the little brown bat Myotis lucifugus. The rabies infection rate among male hoary bats was significantly greater than in either sex of all other submitted species. The frequency of rabies diagnosis in hoary bats submitted during 1979-82 was also significantly higher than in those submitted between 1971 and 1978. There has been a significant decrease in the rabies prevalence or infection rate of little brown bats since 1971-78.  相似文献   

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