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Medicinas Complementárias
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1.
J Med Virol ; 96(1): e29369, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38180269

RESUMEN

Broad-spectrum antivirals (BSAs) have the advantageous property of being effective against a wide range of viruses with a single drug, offering a promising therapeutic solution for the largely unmet need in treating both existing and emerging viral infections. In this review, we summarize the current strategies for the development of novel BSAs, focusing on either targeting the commonalities during the replication of multiple viruses or the systemic immunity of humans. In comparison to BSAs that target viral replication, these immuno-modulatory agents possess an expanded spectrum of antiviral activity. However, antiviral immunity is a double-edged sword, and maintaining immune homeostasis ultimately dictates the health status of hosts during viral infections. Therefore, establishing an ideal goal for immuno-modulation in antiviral interventions is crucial. Herein we propose a bionic approach for immuno-modulation inspired by mimicking bats, which possess a more robust immune system for combating viral invasions, compared to humans. In addition, we discuss an empirical approach to treat diverse viral infections using traditional Chinese medicines (TCMs), mainly through bidirectional immuno-modulation to restore the disrupted homeostasis. Advancing our understanding of both the immune system of bats and the mechanisms underlying antiviral TCMs will significantly contribute to the future development of novel BSAs.


Asunto(s)
Antivirales , Virosis , Animales , Humanos , Antivirales/farmacología , Quirópteros/inmunología , Quirópteros/virología , Homeostasis , Medicina Tradicional China , Virosis/tratamiento farmacológico , Desarrollo de Medicamentos
2.
PeerJ ; 11: e15888, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37719121

RESUMEN

Background: Several insectivorous bat species are found in New England, yet research on them is still scarce. Current research shows the ecological importance of bats due to their control of insect populations, but they are endangered by habitat loss and White Nose Syndrome, among other threats. Pine barrens are an uncommon ecosystem found in New England that supports other rare taxa and could be important for these bat species. Methods: With hand-held audio recorders, we surveyed for bats in Montague Plains Wildlife Management Area in Massachusetts and Concord Pine Barrens in New Hampshire in June 2022. Our study objectives were to (1) describe the most common bat species and (2) compare bat activity across different habitat types at two managed pine barrens in New England. In particular, we examined bat activity related to habitat type (scrub oak, mature pitch pine, treated pitch pine, hardwood forest), habitat structure (i.e., canopy closure), time since prescribed fire, and path width. We analyzed our data through generalized linear modeling and logistic regression. Results: Overall, we were able to measure the presence of five out of the nine total species found in the area, including the endangered Myotis lucifugus (little brown bat). We recorded 293 bat calls, with the majority of calls from big brown bats (71%). We found significant differences (p < 0.05) in bat activity in relation to time since prescribed fire and habitat structure. The index of bat activity was greatest in pitch pine and hardwood forests and lowest in scrub oak and treated pitch pine habitats. With preliminary data, we also found that silver-haired bat presence was influenced by habitat type, with more detections at survey points in hardwood forests. Discussion: These findings demonstrate the importance of pine barrens as an ecosystem that supports bats in New England. According to the activity of bats in our study, closed canopy and mature pitch pine habitats may be prioritized in conservation efforts at managed barrens for bat species. Further research is recommended to better understand the relationship between prescribed fires, which are common in managed barrens, and bat activity.


Asunto(s)
Quirópteros , Esencias Florales , Pinus , Animales , Ecosistema , New England , Bosques , Massachusetts , Eulipotyphla
3.
Vet Med Sci ; 9(6): 2660-2675, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37725331

RESUMEN

BACKGROUND: Ethiopia is one of the countries with richest fauna used for medicinal purpose. The Jimma Arjo community has knowledge and practice of utilizing this medicinal animal for treatment of human and animal ailments. OBJECTIVE: The objective of this research is to assess animals and their products used for treatment of human and animal ailment METHODS: A cross-sectional ethnozoological survey was conducted using a semi structured questionnaire among purposively selected traditional healers resided in Jimma Arjo district. The data collected was entered in Microsoft excel spread sheet and analysed using SPSS statistical software. Fidelity level (FL), use value and informant consensus factor was determined. RESULTS: A total of 33 animal species was found to be used for treating 40 human ailments and different livestock disease confirmed by 36 informants of different ages, sexes and educational backgrounds. The majority of animals (63.63%) were mammals followed by birds (15.15%). Most of the respondents were male, married and aged 55 years and above. Most of the healers learn ethnozoological practice from the father (36.11%) followed by mother (19.44%). The traditional practice is accepted by (72.22%) of the community where 61.11% of the healers are not willing to transfer their knowledge to other. For most of the healers, the reason to practice traditional healing was for treating one's own family or animals (41.67%). The FL was found 100% for honey from Apis mellifera and Trigona spp. for asthma, Cynopterus sphinx for viral skin disease and Crocuta crocuta for bad sprit treatment. In this study, honey from A. mellifera, Hystrix cristata and Sus scrofa domesticus were reported to cure different ailments. CONCLUSION: This study indicated wide use of medicinal animals and their products which could be used as an alternative and complementary medicine or a basis for in developing new drugs because the existing drugs especially antimicrobials are under threat due to the development of resistance by microbes.


Asunto(s)
Quirópteros , Practicantes de la Medicina Tradicional , Humanos , Animales , Masculino , Abejas , Femenino , Etiopía , Estudios Transversales , Medicina Tradicional , Ganado
4.
J Virol ; 97(9): e0079023, 2023 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-37607058

RESUMEN

Bats carry genetically diverse severe acute respiratory syndrome-related coronaviruses (SARSr-CoVs). Some of them utilize human angiotensin-converting enzyme 2 (hACE2) as a receptor and cannot efficiently replicate in wild-type mice. Our previous study demonstrated that the bat SARSr-CoV rRsSHC014S induces respiratory infection and lung damage in hACE2 transgenic mice but not wild-type mice. In this study, we generated a mouse-adapted strain of rRsSHC014S, which we named SMA1901, by serial passaging of wild-type virus in BALB/c mice. SMA1901 showed increased infectivity in mouse lungs and induced interstitial lung pneumonia in both young and aged mice after intranasal inoculation. Genome sequencing revealed mutations in not only the spike protein but the whole genome, which may be responsible for the enhanced pathogenicity of SMA1901 in wild-type BALB/c mice. SMA1901 induced age-related mortality similar to that observed in SARS and COVID-19. Drug testing using antibodies and antiviral molecules indicated that this mouse-adapted virus strain can be used to test prophylactic and therapeutic drug candidates against SARSr-CoVs. IMPORTANCE The genetic diversity of SARSr-CoVs in wildlife and their potential risk of cross-species infection highlights the importance of developing a powerful animal model to evaluate the antibodies and antiviral drugs. We acquired the mouse-adapted strain of a bat-origin coronavirus named SMA1901 by natural serial passaging of rRsSHC014S in BALB/c mice. The SMA1901 infection caused interstitial pneumonia and inflammatory immune responses in both young and aged BALB/c mice after intranasal inoculation. Our model exhibited age-related mortality similar to SARS and COVID-19. Therefore, our model will be of high value for investigating the pathogenesis of bat SARSr-CoVs and could serve as a prospective test platform for prophylactic and therapeutic candidates.


Asunto(s)
Quirópteros , Ratones , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Ratones/virología , Quirópteros/virología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/clasificación , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/efectos de los fármacos , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/patogenicidad , Ratones Endogámicos BALB C , COVID-19/mortalidad , Síndrome Respiratorio Agudo Grave/tratamiento farmacológico , Síndrome Respiratorio Agudo Grave/mortalidad , Pase Seriado , Antivirales/farmacología , Antivirales/uso terapéutico , Anticuerpos Antivirales/farmacología , Anticuerpos Antivirales/uso terapéutico , Zoonosis Virales/tratamiento farmacológico , Zoonosis Virales/transmisión , Zoonosis Virales/virología , Enfermedades Pulmonares Intersticiales/tratamiento farmacológico , Enfermedades Pulmonares Intersticiales/virología , Envejecimiento , Evaluación Preclínica de Medicamentos
5.
Am J Bot ; 110(6): e16199, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37318759

RESUMEN

PREMISE: Many tropical plants are bat-pollinated, but these mammals often carry copious, multispecific pollen loads making bat-pollinated plants susceptible to heterospecific pollen deposition and reproductive interference. We investigated pollen transfer between sympatric bat-pollinated Burmeistera species and their response to heterospecific pollen deposition from each other. METHODS: We quantified conspecific and heterospecific pollen deposition for two populations of B. ceratocarpa, a recipient species in heterospecific pollen transfer interactions, that co-occur with different donor relatives (B. borjensis and B. glabrata). We then used a cross-pollination scheme using pollen mixtures to assess the species' responses to heterospecific pollen deposition in terms of fruit abortion and seed production. RESULTS: Burmeistera ceratocarpa received significantly more heterospecific pollen from its relatives at both sites than its own pollen was deposited on its relatives. However, heterospecific pollen deposition only affected seed production by B. borjensis and B. glabrata, but not by B. ceratocarpa, suggesting that early acting post-pollination barriers buffer the latter against reproductive interference. Crosses between sympatric and allopatric populations suggest that the study species are fully isolated in sympatry, while isolation between allopatric populations is strong but incomplete. CONCLUSIONS: We did not observe evidence of reproductive interference among our study species, because either heterospecific pollen deposition did not affect their seed production (B. ceratocarpa) or they receive heterospecific pollen only rarely (B. borjensis and B. glabrata). Frequent heterospecific pollen deposition might favor the evolution of barriers against foreign pollen (as in B. ceratocarpa) that alleviate the competitive costs of sharing low fidelity pollinators with co-occurring species.


Asunto(s)
Campanulaceae , Quirópteros , Animales , Quirópteros/fisiología , Flores/fisiología , Reproducción/fisiología , Polinización/fisiología , Polen/fisiología
6.
Sci Rep ; 13(1): 7364, 2023 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-37147396

RESUMEN

We present the results of a study which describes the relationship between the western barbastelle Barbastella barbastellus a highly specialised moth predator, and its prey-moths of the genus Orthosia, another selective animal known to converge around a dominant producer of pollen and nectar in early spring-willow trees Salix sp. In order to describe this trophic relationship, we conducted acoustic recordings at five paired sites (willow/control tree) in proximity to known barbastelle hibernation sites (Natura 2000: PLH080003 and PLH200014) beginning in mid-March 2022 after the first willow blossom sighting. Our study confirms a relationship between willow trees and barbastelles during early spring, as their activity around them was significantly higher than control sites. We also explore the activity of barbastelles over time, finding that activity levels around willows significantly decrease from the night of the first recorded bat, while the abundance of non-moth specialist bats remains consistent. Short-time importance (directly after hibernation) of willows for a moth specialist bat is probably due to other species blossom, attracting alternative prey, and in consequence-the bat. This newly described relationship should influence current conservation measures aimed at barbastelles.


Asunto(s)
Quirópteros , Mariposas Nocturnas , Salix , Animales , Estaciones del Año , Polen
7.
PLoS Biol ; 21(2): e3002013, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36802356

RESUMEN

Substantial progress in the field of neuroscience has been made from anaesthetized preparations. Ketamine is one of the most used drugs in electrophysiology studies, but how ketamine affects neuronal responses is poorly understood. Here, we used in vivo electrophysiology and computational modelling to study how the auditory cortex of bats responds to vocalisations under anaesthesia and in wakefulness. In wakefulness, acoustic context increases neuronal discrimination of natural sounds. Neuron models predicted that ketamine affects the contextual discrimination of sounds regardless of the type of context heard by the animals (echolocation or communication sounds). However, empirical evidence showed that the predicted effect of ketamine occurs only if the acoustic context consists of low-pitched sounds (e.g., communication calls in bats). Using the empirical data, we updated the naïve models to show that differential effects of ketamine on cortical responses can be mediated by unbalanced changes in the firing rate of feedforward inputs to cortex, and changes in the depression of thalamo-cortical synaptic receptors. Combined, our findings obtained in vivo and in silico reveal the effects and mechanisms by which ketamine affects cortical responses to vocalisations.


Asunto(s)
Anestesia , Corteza Auditiva , Quirópteros , Ketamina , Animales , Corteza Auditiva/fisiología , Estimulación Acústica , Ketamina/farmacología , Quirópteros/fisiología , Neuronas/fisiología , Percepción Auditiva/fisiología
8.
Ann Bot ; 131(2): 361-372, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36579432

RESUMEN

BACKGROUND AND AIMS: Nectar standing crop has a fundamental role in controlling pollinator movements between flowers and individuals within a population. In bat pollination systems, plants take advantage of the cognitive abilities of nectarivorous bats, which integrate complex perceptions of the quality and spatial distribution of resources. Here, we propose that associations between standing crop and pollen transfer help to reveal the role of nectar as a manipulator of pollinator behaviour. METHODS: We used Harpochilus neesianus Ness (Acanthaceae), a bat-pollinated shrub from the Brazilian Caatinga, as a model system to assess nectar removal effects and standing crop, respectively, over the night and to test associations between the amount of nectar available to pollinators, and pollen import and export. KEY RESULTS: Harpochilus neesianus showed continuous nectar secretion throughout the flower lifespan. Flowers subjected to successive nectar removals produced less nectar than flowers sampled just once, and showed, despite a higher sugar concentration, a lower absolute amount of sugar. Under these conditions, bats may realize that nectar production is decreasing after repeated visits to the same flower and could be manipulated to avoid such already pollinated flowers with little nectar, thus increasing the probability of visits to flowers with a high amount of nectar, and a still high pollen availability on anthers and low pollen deposition on stigmas. We found that during most of the period of anthesis, nectar standing crop volume was positively correlated with the number of pollen grains remaining in the anthers, and negatively with the number of pollen grains deposited on the stigma. CONCLUSIONS: Nectar secretion patterns can function as a manipulator of pollinating bats in H. neesianus. We propose that the assessment of variability in nectar secretion in response to removal, and the correlation between nectar standing crop and relative pollen transfer throughout anthesis should be considered in order to understand the role of nectar in the manipulation of pollinators.


Asunto(s)
Quirópteros , Néctar de las Plantas , Animales , Quirópteros/fisiología , Aves/fisiología , Polinización/fisiología , Flores/fisiología , Polen/fisiología , Azúcares
9.
J Zoo Wildl Med ; 53(3): 528-536, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36214237

RESUMEN

Egyptian fruit bats (Rousettus aegyptiacus) are commonly held within zoos and research facilities. Despite this popularity, there have been no publications regarding normal bone density or bone mineral concentration and few publications regarding the normal dietary requirements of calcium, phosphorus, and vitamin D (25-hydrox-vitamin D3 [25(OH)D3]) for the species. A clinical investigation into frequent fractures in a zoo population of 23 adult male Egyptian fruit bats used dual-energy X-ray absorptiometry (DXA) to evaluate bone mineral density (BMD) and bone mineral content (BMC) prior to and after dietary adjustment of calcium and phosphorus. This study documents BMD, BMC, serum trace minerals, and serum levels of 25(OH)D3 within this population and includes postmortem bone density and bone ash from a subset of bats that died during the study period. A handheld point-of-care analyzer was utilized to assess ionized calcium and electrolytes (sodium, potassium, chloride, total CO2), glucose, blood urea nitrogen, and creatinine at each DXA time point to contribute to published reference ranges for this species. This study identified a significant (P < 0.001) increase in BMC over 15 mon (4.71-8.26 g) following additional calcium and phosphorus supplementation in the diet. The BMD also trended toward a significant increase (0.124-0.274 g/cm2, P < 0.053). Additional studies documenting normal bone density that include both sexes and possibly free-ranging bats consuming a natural diet are recommended to determine normal values for R. aegyptiacus.


Asunto(s)
Quirópteros , Oligoelementos , Absorciometría de Fotón/veterinaria , Animales , Densidad Ósea , Calcio , Calcio de la Dieta , Dióxido de Carbono , Cloruros , Creatinina , Femenino , Glucosa , Humanos , Masculino , Minerales , Fósforo , Potasio , Sodio , Vitamina D
10.
J Ethnobiol Ethnomed ; 18(1): 43, 2022 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-35659249

RESUMEN

BACKGROUND: Fruit bats play an important role in pollination and seed dispersal, and their conservation is important to maintain the productivity of some crops and natural ecosystems. The objective of this study was to investigate the knowledge, attitudes, and perception of fruit bats by orchard farmers and agricultural communities in Pakistan. METHODS: The present survey was conducted in two districts (i.e. Sheikhupura and Malakand districts) within Punjab and Khyber Pakhtunkhwa provinces based on the higher number of fruit growing areas and bat roosting sites. A total of 200 (100 per district) close-ended questionnaires with 53 questions were administered to randomly selected respondents within the selected communities associated with fruit orchards, including orchard owners, laborers, and members of the surrounding community. Each questionnaire was divided into seven sections (i.e., demographic information, environmental and public health effects of bats, knowledge about bats, perception and control of bats, non-lethal methods adopted to control bats, and different myths about bats). RESULTS: A majority of respondents (59%, n = 118) mis-classified bats as birds instead of mammals despite more than 84% reporting that they have observed bats. Nearly 71.5% of orchard farmers perceived that their fruits are contaminated by bats during consumption, and a majority believe that bats destroy orchards (62.5%) and are responsible for spreading disease. Mythology about bats was ambiguous, as 49% of those surveyed did not perceived bats to bring good luck (49%), and 50% did not perceived them to be bad omens either. Most respondents have never killed a bat (68%) nor would they kill a bat if given the opportunity (95%). Regarding the control of bats, the greatest percentage of respondents strongly disagree with shooting bats (36%) and strongly agree with leaving bats alone (42.5%). CONCLUSIONS: This study provides a better understanding of the sociodemographic factors associated with knowledge, attitude and perception of bats from fruit orchard owners, labourers and local people. We recommend educational interventions for targeted groups in the community, highlighting the ecosystem services and importance of bat conservation to improve people's current knowledge regarding the role of bats and reduce direct persecution against bats.


Asunto(s)
Quirópteros , Animales , Actitud , Ecosistema , Agricultores , Humanos , Pakistán
11.
New Phytol ; 235(4): 1629-1640, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35194792

RESUMEN

The evolution of floral traits is often considered to reflect selection for increased pollination efficiency. Known as the pollination-precision hypothesis, increased pollination efficiency is achieved by enhancing pollen deposition on precise areas of the pollinator. Most research to date addressing this hypothesis has examined plant species that are a priori predicted to place pollen precisely, but we still lack comparisons with species predicted to have low pollination efficiency. We studied 39 plant species with diverse floral morphologies and measured the precision of pollen placement on two pollinator groups: honey bees (genus Apis) and nectar bats (family Pteropodidae). Pollen was collected from four locations of each pollinator's body (bees: dorsal thorax, ventral thorax, dorsal abdomen, ventral abdomen; bats: crown, face, chest, wing) to calculate pollen placement precision using Pielou's evenness index. We also quantified variation in floral design by scoring floral symmetry, corolla fusion, floral orientation and stamen number. We confirm the importance of four floral character states (bilateral symmetry, fused corollas, horizontal orientation and reduced stamen number) in promoting precise pollen placement on diverse pollinators. Our findings provide phylogenetically corrected, empirical support that the evolution of the four floral characters reflect selection for enhanced precision of pollen placed on pollinators.


Asunto(s)
Quirópteros , Polinización , Animales , Abejas , Flores , Néctar de las Plantas , Polen
12.
PLoS One ; 17(2): e0262985, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35113889

RESUMEN

The Dilleniaceae is known to produce nectarless flowers pollinated by bees, but the fact that bats ingest Dillenia biflora pollen led us to question pollination assumptions for these trees. We aimed to identify the pollinators of D. biflora, check for nectar presence, and investigate potential for cleistogamy and global prevalence of this pollination system. We examined aspects of the pollination of D. biflora on two Fijian islands using video recordings, direct observations, hand pollination, measurements (flowers, bite marks, nectar), and monitoring. The flowers, receptive for one night, contained copious nectar and had permanently closed globose corollas that required removal by bats for pollination. All the 101 flowers that retained their corolla died and did not produce seeds by cleistogamy. The bat Notopteris macdonaldi was well adapted to corolla removal. Keeping corollas closed until bats manipulate the nectar-rich flowers is a beneficial strategy in high-rainfall environments with many flower parasites. We propose to name a pollination system reliant exclusively on bats "chiropteropisteusis." From clues in the literature, other species in the geographical range of Dillenia are probably chiropteropisunous. Chiropteropisteusis should be investigated in the Old-World range of Dillenia, many species of which are threatened. The remarkable "fall" of the entire corolla observed by an earlier botanist for several species in the genus is most likely attributable to bats. This discovery has important implications for the conservation of bat-dependent trees and their associated fauna, particularly considering the high level of threat faced by flying-foxes globally.


Asunto(s)
Quirópteros/fisiología , Dilleniaceae/fisiología , Flores/fisiología , Néctar de las Plantas/fisiología , Polen/química , Polinización , Animales
13.
Sci Rep ; 12(1): 375, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-35013500

RESUMEN

Faeces Vespertilionis is a commonly used fecal traditional Chinese medicine. Traditionally, it is identified relying only on morphological characters. This poses a serious challenge to the composition analysis accuracy of this complex biological mixture. Thus, for quality control purposes, an accurate and effective method should be provided for taxonomic identification of Faeces Vespertilionis. In this study, 26 samples of Faeces Vespertilionis from ten provinces in China were tested using DNA metabarcoding. Seven operational taxonomic units (OTUs) were detected as belonging to bats. Among them, Hipposideros armiger (Hodgson, 1835) and Rhinolophus ferrumequinum (Schober and Grimmberger, 1997) were the main host sources of Faeces Vespertilionis samples, with average relative abundances of 59.3% and 24.1%, respectively. Biodiversity analysis showed that Diptera and Lepidoptera were the most frequently consumed insects. At the species level, 19 taxa were clearly identified. Overall, our study used DNA metabarcoding to analyze the biological composition of Faeces Vespertilionis, which provides a new idea for the quality control of this special traditional Chinese medicine.


Asunto(s)
Productos Biológicos/uso terapéutico , Quirópteros/genética , Código de Barras del ADN Taxonómico , Heces , Medicina Tradicional China , Animales , Biodiversidad , Productos Biológicos/normas , Quirópteros/clasificación , Dieta , Dípteros/genética , Lepidópteros/genética , Medicina Tradicional China/normas , Control de Calidad
14.
eNeuro ; 9(1)2022.
Artículo en Inglés | MEDLINE | ID: mdl-34903526

RESUMEN

There is consensus that primary auditory cortex (A1) utilizes a combination of rate codes and temporally precise population codes to represent discreet auditory objects. During the response to auditory streams, forward suppression constrains cortical rate coding strategies, but it may also be well positioned to enhance temporal coding strategies that rely on synchronized firing across neural ensembles. Here, we exploited the rapid temporal dynamics of bat echolocation to investigate how forward suppression modulates the cortical ensemble representation of complex acoustic signals embedded in echo streams. We recorded from auditory cortex of anesthetized free-tailed bats while stimulating the auditory system with naturalistic biosonar pulse-echo sequences covering a range of pulse emission rates. As expected, increasing pulse repetition rate significantly reduced the number of spikes per echo stimulus, but it also increased spike timing precision and doubled the information gain. This increased spike-timing precision translated into more robust inter-neuronal synchronization patterns with >10-dB higher signal-to-noise ratios (SNRs) at the ensemble level. We propose that forward suppression dynamically mediates a trade-off between the sensitive detection of isolated sounds versus precise spatiotemporal encoding of ongoing sound sequences in auditory cortex.


Asunto(s)
Corteza Auditiva , Quirópteros , Ecolocación , Estimulación Acústica , Animales , Corteza Auditiva/diagnóstico por imagen , Corteza Auditiva/fisiología , Quirópteros/fisiología , Ecolocación/fisiología , Neuronas/fisiología , Sonido
15.
Naturwissenschaften ; 108(5): 46, 2021 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-34581964

RESUMEN

An asynchronous fruit-ripening strategy can enhance the chance of seed dispersal by providing ripe fruits for an extended period to foragers. However, mechanisms associated with this strategy that can facilitate seed dispersal are understudied. This study aimed to investigate whether the chemical components (minerals and secondary metabolites) of a bat fruit with ripening asynchrony change along its ontogeny (Rubiaceae: Neolamarckia cadamba). We predicted that the seed-to-pulp ratio would increase along with fruit ripeness. The chemical components of the fruit were also predicted to change along their ontogenesis in favour of fruit selection and seed dispersal by fruit bats. Our study shows that the asynchronous fruiting strategy limited the number of ripe fruits daily so that fruits were available at a steady rate. As predicted, the seed-to-pulp ratio of each fruit increased along with fruit development. A fruit's mineral concentration also increased as fruit developed, with a sharp jump at full ripeness, when fruit colour also changed. In contrast, the concentration of secondary metabolite compositions decreased gradually during the process of ontogeny. Fruit bats (Pteropodidae: Pteropus giganteus and Cynopterus sphinx) were the only nocturnal frugivore visitors of these trees and their fruit selection was driven by fruit size and colour. Both bats preferably consumed ripe fruits, which had a higher concentration of attractants (essential minerals) and a lower concentration of deterrents (secondary metabolites), supplemented with a higher seed-to-pulp ratio. The bats exhibited different foraging patterns and home ranges resulting in dispersal (as measured by feeding roost location) occurring across different spatial scales. Our study shows that the chemical components involved in an asynchronous fruit-ripening process could select for extended fruit availability by intensifying the demand for each ripe fruit among legitimate seed dispersers, which increases the likelihood of fruits being dispersed away from parent crowns.


Asunto(s)
Quirópteros , Rubiaceae , Dispersión de Semillas , Animales , Frutas , Semillas
16.
J Zoo Wildl Med ; 52(2): 806-814, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34130429

RESUMEN

The Milwaukee County Zoo has housed common vampire bats (Desmodus rotundus) since 1973. The bats are fed defibrinated cow's blood supplemented with a liquid pediatric multivitamin. From July 2013 to May 2014, multiple deaths occurred in colony bats, including five juveniles with multiple bone fractures and failure of endochondral ossification, three adults with cerebellar necrosis, and one adult with subcutaneous hemorrhage. In November 2013, an adult bat developed a nonhealing left wing hematoma and eventually succumbed 9 mo later. A postmortem examination revealed multifocal extensive necrohemorrhagic and suppurative ulcerative dermatitis with no underlying cause determined. From July to December 2014, five of nine adult bats in the colony developed similar hematomas along with gingival bleeding. One euthanized bat had a serum ascorbic acid level of 0.08 mg/dl and marked generalized subcutaneous hemorrhage. A therapeutic trial was initiated in which two bats received defibrinated cow's blood supplemented only with oral vitamin C, 100 mg/kg PO q24h for 3 d, and then 50 mg/kg PO q24h. Two other bats received nonsupplemented defibrinated cow's blood and were given vitamin K 3.3 mg/kg SC q12h for 3 d, and then 3.3 mg/kg SC q24h for 7 d. The bats supplemented with vitamin C improved, supporting a diagnosis of vitamin C deficiency. All bats were subsequently supplemented with vitamin C leading to resolution of all lesions within 10 d to 2 mo. Vitamin C is necessary for collagen synthesis, which is required for proper wound healing, capillary and cartilage strength, osteoid production, and pial membrane formation of the cerebellum. Several bat species cannot synthesize vitamin C and require a dietary source. This is the first report of vitamin C deficiency in a colony of vampire bats leading to severe chronic subcutaneous hemorrhage, bone fragility, microfractures, cerebellar necrosis, and death.


Asunto(s)
Deficiencia de Ácido Ascórbico/veterinaria , Ácido Ascórbico/uso terapéutico , Quirópteros , Suplementos Dietéticos , Vitaminas/uso terapéutico , Animales , Animales de Zoológico , Ácido Ascórbico/administración & dosificación , Deficiencia de Ácido Ascórbico/patología , Vitaminas/administración & dosificación
17.
PLoS One ; 16(5): e0250857, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34010334

RESUMEN

Habitat loss and alteration are two of the biggest threats facing insular flying-foxes. Altered habitats are often re-vegetated with introduced or domestic plant species on which flying-foxes may forage. However, these alien food plants may not meet the nutritional requirements of flying-foxes. The critically endangered Christmas Island flying-fox (CIFF; Pteropus natalis) is subject to habitat alteration and the introduction of alien food plants, and therefore is a good model species to evaluate the potential impact of alien plant species on insular flying-foxes. In this study, we evaluated nutritional content of native food plants to determine how flying-foxes historically met their nutritional requirements. Furthermore, we compared the nutritional content of native and alien fruits to predict possible impacts of alien plants on insular flying-foxes. Native and alien fruits and flowers, and native foliage (leaves, petals, and petioles) commonly consumed by the CIFF were collected and evaluated for soluble sugars, crude protein, non-fiber carbohydrates, and nine minerals. Evaluation of native food plants suggests that flying-foxes meet energy requirements by consuming fruit and nectar. However, fruit and nectar are low in protein and essential minerals required for demanding life periods; therefore, flying-foxes likely supplement their diets with pollen and foliage. Thus, flying-foxes require a diverse array of plants to meet their nutritional requirements. Compared to native fruits, alien fruits contained significantly higher non-fiber carbohydrates, and this may provide an important energy source, particularly from species that bear fruit year-round. Median mineral concentrations in alien fruit species, however, were deficient compared to native fruits, suggesting major (or even seasonal) shifts in the proportion of alien species in the CIFF diet could lead to nutritional imbalances. This study confirms the need to quantify nutritional parameters in addition to feeding ecology when evaluating habitat quality to inform conservation actions that can be applied both locally and globally.


Asunto(s)
Quirópteros/fisiología , Especies en Peligro de Extinción , Valor Nutritivo , Plantas Comestibles , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Australia , Biodiversidad , Conservación de los Recursos Naturales , Dieta/veterinaria , Ecosistema , Frutas/química , Especies Introducidas , Necesidades Nutricionales , Plantas Comestibles/química , Polinización , Dispersión de Semillas
18.
Artículo en Inglés | MEDLINE | ID: mdl-33835199

RESUMEN

To perform adaptive behaviours, animals have to establish a representation of the physical "outside" world. How these representations are created by sensory systems is a central issue in sensory physiology. This review addresses the history of experimental approaches toward ideas about sensory coding, using the relatively simple auditory system of acoustic insects. I will discuss the empirical evidence in support of Barlow's "efficient coding hypothesis", which argues that the coding properties of neurons undergo specific adaptations that allow insects to detect biologically important acoustic stimuli. This hypothesis opposes the view that the sensory systems of receivers are biased as a result of their phylogeny, which finally determine whether a sound stimulus elicits a behavioural response. Acoustic signals are often transmitted over considerable distances in complex physical environments with high noise levels, resulting in degradation of the temporal pattern of stimuli, unpredictable attenuation, reduced signal-to-noise levels, and degradation of cues used for sound localisation. Thus, a more naturalistic view of sensory coding must be taken, since the signals as broadcast by signallers are rarely equivalent to the effective stimuli encoded by the sensory system of receivers. The consequences of the environmental conditions for sensory coding are discussed.


Asunto(s)
Acústica , Vías Auditivas/fisiología , Percepción Auditiva , Conducta Animal , Ambiente , Arquitectura y Construcción de Instituciones de Salud , Insectos/fisiología , Sonido , Estimulación Acústica , Adaptación Psicológica , Animales , Quirópteros/fisiología , Señales (Psicología) , Patrones de Reconocimiento Fisiológico , Conducta Predatoria , Localización de Sonidos
19.
Medicina (Kaunas) ; 57(2)2021 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-33673004

RESUMEN

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused a global pandemic and is posing a serious challenge to mankind. As per the current scenario, there is an urgent need for antiviral that could act as a protective and therapeutic against SARS-CoV-2. Previous studies have shown that SARS-CoV-2 is much similar to the SARS-CoV bat that occurred in 2002-03. Since it is a zoonotic virus, the exact source is still unknown, but it is believed bats may be the primary reservoir of SARS-CoV-2 through which it has been transferred to humans. In this review, we have tried to summarize some of the approaches that could be effective against SARS-CoV-2. Firstly, plants or plant-based products have been effective against different viral diseases, and secondly, plants or plant-based natural products have the minimum adverse effect. We have also highlighted a few vitamins and minerals that could be beneficial against SARS-CoV-2.


Asunto(s)
Antivirales/uso terapéutico , Productos Biológicos/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Nutrientes/uso terapéutico , SARS-CoV-2/efectos de los fármacos , Virosis/tratamiento farmacológico , Animales , Quirópteros/virología , Humanos
20.
Chemosphere ; 275: 129985, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33640742

RESUMEN

Tebuconazole (TEB) is a triazole fungicide widely used in agriculture known to cause metabolic and endocrine disorders in mammals. Several plant extracts have shown to be beneficial against pesticide effects due to their hepatoprotective, antioxidant and anti-inflammatory properties. As fruit bats play a critical role in rainforest regeneration and are constantly exposed to pesticides, we aimed at evaluating TEB-induced toxicity and the possible protective effect of the Ficus carica plant extract in Neotropical fruit-eating bats (Artibeus lituratus). Bats were captured and assigned to 4 experimental groups, offered: 1) CTL (n = 6): papaya; 2) DMSO (n = 6): papaya treated with 1.25% dimethyl sulfoxide (DMSO); 3) TEB (n = 6): papaya treated with tebuconazole (commercial formulation) 0.1%; and 4) TEBFC (n = 6): papaya treated with tebuconazole 0.1% and Ficus carica extract (20%) in DMSO (1.25%). After seven days of exposure, TEB bats showed increased lipid peroxidation, increased superoxide dismutase (SOD) and catalase (CAT) activities, vascular congestion and inflammatory infiltrate in the liver, and increased serum transaminase enzyme activities. We found the same alterations in oxidative stress parameters in the breast muscles of TEB-exposed bats. In the testes, all oxidative stress markers were increased in TEB bats and corroborate findings of histopathological and increased serum testosterone levels observed following TEB exposure. The co-administration of the fungicide with the F. carica plant extract attenuated most oxidative stress markers in exposed bats' liver and testes and decreased liver damage, but failed to revert the steroid imbalance caused by the fungicide exposure.


Asunto(s)
Quirópteros , Ficus , Animales , Estrés Oxidativo , Extractos Vegetales , Triazoles/toxicidad
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