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Desmodus rotundus (Chiroptera: Phyllostomidae; Desmodontinae) is the most common vampire bat and has a broad distribution, ranging from southern Mexico to central Chile in the west, and Paraguay and northern Argentina in the east of South America ( Koopman 1988 ). Because of its feeding habit, this bat is considered the main source of rabies transmission to cattle. Although this species has a large spectrum of morphological variability throughout its range, thus far no study has examined the distribution of genetic lineages over its geographic range. Four geographically circumscribed clades of D. rotundus were described in the Brazilian territory on the basis of mitochondrial sequence analyses: southern Atlantic forest (SAF), northern Atlantic forest (NAF), Pantanal (PAN) and Amazon plus Cerrado (AMC) clade. The differentiation among these clades is strongly supported statistically, although the phylogenetic relationship between them remains uncertain. The extremely high levels of sequence divergence that were found between clades (ranging from 6% to 11%) are the highest ever described for a Neotropical bat species and cannot be explained by female philopatry alone. This indicates that D. rotundus comprises two or more distinct, possibly cryptic species. The biogeographic pattern described for this bat is similar to those described for other bats and terrestrial mammals, suggesting geographical congruence between historical vicariant processes, including likely vicariant events between north and south Atlantic Forest and between the Atlantic Forest and the Amazon.  相似文献   

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The type AB pineal body of the common vampire bat, Desmodus rotundus, was recessed and lobulated, was extensively vascularized and intimately related to great veins, and was unassociated with the epithalamic region. The habenular and the posterior commissures coursed anteriorly and were unassociated with the pineal. The saccular suprapineal recess of the third ventricle extended dorsally juxtaposed to the pineal body. These anatomical features are likely to make pinealectomies in the vampire more difficult to manage. The pineal parenchyma consisted of light pinealocytes surrounded by canaliculi of various sizes, often transmitting unmyelinated nerve fibers and glial processes. Desmosomes were common. The pinealocyte nuclei were large and highly infolded; characteristic cytoplasmic constituents included abundant dilated Golgi complexes associated with clear vesicles, numerous polyribosomes, few single cisternae of ribosome-studded rough endoplasmic reticulum, mitochondria, and occasional multivesicular bodies and lysosomes. Almost all pinealocytes exhibited centrioles and some, in addition, displayed basal bodies but rarely ciliary shafts. A conspicuous feature of the pinealocyte cytoplasm was the presence of branched bundles of intermediate filaments, especially in the perinuclear zone. Siderotic macrophages, lipofuscin-pigment-containing phagocytic cells, mast cells, myelin bodies, and both fenestrated and continuous capillaries were present. The perivascular compartment was densely packed with unmyelinated nerve bundles containing small to large fibers exhibiting axoaxonic densities. Other constituents of the perivascular compartment were club-shaped pinealocyte processes filled with clear vesicles, microtubules, an occasional mitochondrion, glial processes, and collagen fibers. "Synapselike" contacts were observed between the axons and pinealocyte processes. Abundant pinocytotic vesicles in the capillary endothelium indicated active pinocytosis. Myelinated nerve fibers were lacking. The pineal ultrastructure of Desmodus is in part unlike that reported for other mammals, including bats.  相似文献   

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Background  

The common vampire bat Desmodus rotundus is one of three bat species that feed exclusively on the blood of mammals often more than 1000 times its size. Vampire bats even feed on human blood. Moreover, they tend to feed on the same individual over consecutive nights.  相似文献   

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This study addresses the composition of microbial flora in the vampire bat (Desmodus rotundus) primarily because all available data are outdated, and because of the economical significance of this bat species. Twenty-one bats were collected and their aerobic bacteria documented separately for stomach and intestine. Bacteria were identified through the Analytical Profile Index (API), and results analyzed with the APILAB software. A total of thirty bacterial species were isolated from sixteen females and five males. The most common species were Escherichia coli and Staphylococcus aureus, although other bacteria, such as Acinetobacterjohnsonii, Enterobacter sakazakii, Staphylococcus chromogenes, S. hyicus and S. xylosus were also common. The number of species found in the stomach and intestine was significantly different, and the intestine presented a higher diversity compared to the stomach. This has previously been found in other mammals and it is attributed to a reduction of acidity. Most of the species found in this study are considered normal components of the digestive tract of mammals, although other bacteria common in the skin of mammals and from aquatic environments were found. Bacteria from the skin may invade the vampire's stomach and/or intestine when the bat has contact with its prey, and may suggest that the vampire's feeding habit facilitates the invasion of other microbes not common in its digestive tract. The fact that bacteria from aquatic environments were also found suggests that D. rotundus, as previously found by other researchers, drinks free water when available, and water may be another source of microbial invasion.  相似文献   

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The testicular stroma of the vampire bat including the testicular capsula and the lamina propria of the seminiferous tubuli, was strongly PAS-positive. This observation was a possible indication of great amounts of structural glycogen and other glycoconjugates at the level of smooth muscle cells; elongated contractile cells and/or collagen frameworks of the tunica albuginea and tubular lamina propria. In the last the basement membranes of the seminiferous tubules were particularly strongly PAS positive, as an indication of their neutral mucosubstances structural composition, previously described (Malmi et al., 1987). The epithelium lining from the cavitary and surface rete testis complex showed low reactivities to mucosubstances; total proteins and lipids and oxidative enzymes studied. Although the apical granulation at the rete testis epithelium showed an intense PAS reactivity with hypothesis of glycoprotein secretion, through the rete. The PAS, Sudan Black B, NADH, MDH and LDH reactions of the testicular interstitium seem correlate to steroid metabolism (biosynthesis and secretion), at the Leydig cells level. The seminiferous epithelium generally had low reactions to all the histochemical studies realized. Particularly in the adbasal compartment the histochemical localizations of NADH diaphorase and LDH were possible related to glycolytic activities and general carbohydrates metabolism, both enzymes, and hydrogen transport, the NADH. The strong PAS, diastase and PAS, and alcian blue pH 2.5 and PAS reactions observed in the adluminal seminiferous epithelium compartment were directly related to the spermatids acrosomal glycoconjugates structuration. Also the SDH localization at this level seems to be related to the mitochondrial activities at the middle piece level in the late spermatids.  相似文献   

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The common vampire bat (Desmodus rotundus) is one of three haematophagous species of bats and the only species in this genus. These New World bats prey on mammals and create significant economic impacts through transmission of rabies in areas where livestock are prevalent. Furthermore, in some portions of their range, it is not uncommon for them to prey upon humans. It is critical to the management of this species and for understanding the spread of bat rabies that detailed studies of D. rotundus population structure be conducted. To further such studies, we have characterized 12 microsatellite loci for this species.  相似文献   

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Summary Three vampire bats (Desmodus rotundus) were trained in a two-choice apparatus (Fig. 1) to select the one of two passages that contained a vertical stick or narrow metal strip at a distance of 45 cm. To single sticks in isolation they responded at a width of 1.1 mm or more. Large surfaces in the vicinity of the target impaired the locating ability; the animals correctly choose a 20-mm-wide strip 2.5 cm in front of a strongly reflecting plate (Fig. 2) or 6 cm away on one side of it (Fig. 3).In a flight tunnel the response to single vertical obstacles of various size was studied. The sudden increase in echolocation-sound repetition rate as the obstacle was approached marked the response distance. This distance was 50–80 cm for thread obstacles 0.5 mm thick; the threshold diameter was 0.23 mm (Fig. 6). When the obstacles were mounted in a 30-cm-wide constriction of the tunnel the response occurred later; even a 10-mm-wide strip did not elicit a change in the sound pattern until the bats had approached to a distance of 60 cm (Fig. 6). The response distance increased significantly when the obstacles were moved in front of or beyond the constriction (Fig. 8).  相似文献   

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Structurally the boundary tissue of the vampire bat seminiferous tubuli showed 2 to 5 layers of connective tissue in which elongated contractile cells and lamellar and/or fibrillar collagen were noticed. This boundary tissue forms the seminiferous tubular lamina propria. Its structure was more complex around the seminiferous tubuli near the Capsula testicularis than between the adjacent and contiguous tubuli into the testicular lobuli. The whole ultrastructural organization of the seminiferous lamina propria was described here.  相似文献   

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The vampire bat pectoralis muscle contains at least four fiber types distributed in a nonhomogeneous pattern. One of these fiber types, here termed IIe, can be elucidated only by adenosine triphosphatase (ATPase) histochemistry combined with reactions against antifast and antislow myosin antibodies. The histochemical and immunohistochemical observations indicate a well-developed specialization of function within specific regions of the muscle. In parallel, analyses of native myosin isoforms and myosin heavy chain isoforms indicate two points. First, the histochemical “type IIe” fiber is predominant in cranial portions of the muscle, and myosin extracted from these regions exhibits a unique electrophoretic mobility not observed in the myosin isoforms of more traditional laboratory mammals. Second, the type I fibers are confined to the pectoralis abdominalis muscle and a small adjacent region of the caudal part of the pectoralis. This pattern of type I fiber distribution is considered a derived character state compared to muscle histochemical phenotype and isoform composition in the pectoralis muscles of other phyllostomids we have studied (Artibeus jamaicensis, Artibeus lituratus, Carollia perspicillata). We relate this to the unique locomotory needs of the common vampire bat, Desmodus rotundus. © 1993 Wiley-Liss, Inc.  相似文献   

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Complementary DNAs coding for four Desmodus rotundus salivary plasminogen activators (DSPAs) were isolated and characterized. The predicted amino acid sequences display structural features also found in tissue-type plasminogen activator. The largest forms (DSPA alpha 1 and -alpha 2) contain a signal peptide, a finger (F), an epidermal growth factor (EGF), a kringle, and a serine protease domain, whereas DSPA beta and -gamma lack the F and F-EGF domains, respectively. Additional differences between the four forms suggest that distinct genes code for the members of the DSPA family. Transfection of DSPA-encoding cDNAs, placed under the control of the simian virus 40 late promoter, into COS-1 cells resulted in the secretion of highly fibrin-dependent PAs.  相似文献   

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The distribution and frequency of gastro-entero-pancreatic (GEP) endocrine cells were studied in vampire bats by immunocytochemistry. Moderate numbers of somatostatin- and a few 5-hydroxytryptamine (5-HT)- and glucagon-immunoreactive cells were seen in the fundic cecum of the stomach. Numerous gastrin- and moderate numbers of somatostatin- and 5-HT-immunoreactive cells were found in the pyloric region. Moderate numbers of 5-HT-, somatostatin-, and gastrin-immunoreactive cells also were found in BRUNNER's glands. In addition to the above-mentioned 4 immunoreactive cell types, cells immunoreactive for glicentin, secretin, cholecystokinin (CCK), gastric inhibitory peptide (GIP), and neurotensin were found in the intestine. Numerous insulin-, moderate numbers of somatostatin- and glucagon-, and a few 5-HT-immunoreactive cells were detected in the pancreatic islets with lesser numbers scattered within the exocrine pancreas. Motilin- and pancreatic polypeptide-immunoreactive cells were not observed in this study.  相似文献   

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This paper provides new data on chromosomes of Brazilian vampire bats Desmodus rotundus and Diphylla ecaudata. These species were analyzed by GTG, CBG- and CB-DAPI banding, AgNO3/CMA3 sequential staining, base-specific fluorochrome dyes and in situ hybridization with 18S rDNA probe. C-banding (CBG) revealed constitutive heterochromatin in the pericentromeric regions in all autosomes and the X and Y chromosomes appeared entirely heterochromatic in both species. CB-DAPI revealed a coincident banding pattern to that obtained by CBG. Triple staining CMA3/DA/DAPI revealed an R-banding and a weak G-banding pattern in the karyotypes. Sequential AgNO3/CMA3 staining showed a NOR located interstitially on the long arm of pair 8 in D. rotundus and on the short arm of pair 13 in D. ecaudata. FISH with a rDNA probe confirmed the location and number of NORs; a difference neither in intensity nor in size of hybridization signal was detected between homologues for both species.  相似文献   

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Background  

The role of Pleistocene glacial oscillations in current biodiversity and distribution patterns varies with latitude, physical topology and population life history and has long been a topic of discussion. However, there had been little phylogeographical research in south China, where the geophysical complexity is associated with great biodiversity. A bird endemic in Southeast Asia, the Grey-cheeked Fulvetta, Alcippe morrisonia, has been reported to show deep genetic divergences among its seven subspecies. In the present study, we investigated the phylogeography of A. morrisonia to explore its population structure and evolutionary history, in order to gain insight into the effect of geological events on the speciation and diversity of birds endemic in south China.  相似文献   

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