Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
1.
J Helminthol ; 98: e46, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38828715

RESUMEN

A comparative analysis of taxonomic diversity on shrew cestodes among four islands in the Sea of Japan and the Sea of Okhotsk (Sakhalin, Kunashir, Hokkaido, and Moneron) was performed. Cestode species shared among the islands were identified and their host specificity was investigated. On Sakhalin Island, 33 species of the families Hymenolepididae, Dilepididae and Mesocestoididae were recorded in four shrew species (Sorex caecutiens, S. gracillimus, S. minutissimus and S. unguiculatus). In S. caecutiens, S. gracillimus, and S. unguiculatus on Kunashir Island, 22 species of the same families were found and, on Hokkaido Island, 23 species of the families Hymenolepididae and Dilepididae were recorded. On Moneron Island, three species of cestodes were registered in S. tundrensis. The Sakhalin-Hokkaido-Kunashir complex of shrew cestodes includes eastern-Palearctic, trans-Palearctic and endemic species. High endemism (~22%) of shrew tapeworms in the Sakhalin-Kunashir-Hokkaido Islands was noted as compared to continental territories. The different numbers of cestode species in S. unguiculatus (31), S. caecutiens (29), S. gracillimus (19) and S. minutissimus (1) were found. It was concluded that the cestodes species diversity of shrews of Sakhalin-Kunashir-Hokkaido depended primarily on the history of island formation, their modern physical and geographical features, the abundance of definitive and intermediate cestodes hosts and, to a lesser extent, on the size and remoteness of the islands from the mainland and the diversity of host species.


Asunto(s)
Biodiversidad , Cestodos , Especificidad del Huésped , Islas , Musarañas , Animales , Cestodos/clasificación , Cestodos/aislamiento & purificación , Cestodos/genética , Musarañas/parasitología , Japón , Infecciones por Cestodos/veterinaria , Infecciones por Cestodos/parasitología , Infecciones por Cestodos/epidemiología
2.
Parasitology ; 148(1): 63-73, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33087188

RESUMEN

The causal chain of parasite-host-environment interactions, the so-called 'dual parasite environment', makes studying parasites more complicated than other wild organisms. A sample of 65 282 fleas taken from 336 different locations were analysed for changes in the distribution, diversity and compensation of flea communities found on small mammals along an elevational diversity gradient ranging from the Pannonian Plain to the base of the Carpathian summits. The fleas were divided into four groups, which were derived from changes in abundance and occurrence determined from cluster analysis. They are (1) flea species whose range seems unrelated to any change in elevation; (2) species that avoid high altitudes; (3) a group that can be subdivided into two types: (i) host-specific fleas and (ii) mountains species and (4) species opting for high altitudes on the gradient or preferring lower to middle elevations below 1000 m. Our study showed a unimodal pattern of flea diversity along the elevational gradient. It indicated that seasonality significantly conditions changes in biodiversity and patterns of spatial change along the elevational gradient, with specific flea species influenced by their host, while the impact of environmental conditions is more pronounced in opportunistic flea species.


Asunto(s)
Altitud , Mamíferos/parasitología , Siphonaptera , Animales , Animales Salvajes/parasitología , Biodiversidad , Ecosistema , Infestaciones por Pulgas/parasitología , Especificidad del Huésped , Interacciones Huésped-Parásitos , Roedores/parasitología , Siphonaptera/clasificación , Siphonaptera/fisiología , Eslovaquia
3.
Mol Phylogenet Evol ; 141: 106605, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31479732

RESUMEN

The origin of the mammalian order Eulipotyphla has been debated intensively with arguments around whether they began diversifying before or after the Cretaceous-Palaeogene (K-Pg) boundary at 66 Ma. Here, we used an in-solution nucleotide capture method and next generation DNA sequencing to determine the sequence of hundreds of ultra-conserved elements (UCEs), and conducted phylogenomic and molecular dating analyses for the four extant eulipotyphlan lineages-Erinaceidae, Solenodontidae, Soricidae, and Talpidae. Concatenated maximum-likelihood analyses with single or partitioned models and a coalescent species-tree analysis showed that divergences among the four major eulipotyphlan lineages occurred within a short period of evolutionary time, but did not resolve the interrelationships among them. Alternative suboptimal phylogenetic hypotheses received consistently the same amount of support from different UCE loci, and were not significantly different from the maximum likelihood tree topology, suggesting the prevalence of stochastic lineage sorting. Molecular dating analyses that incorporated among-lineage evolutionary rate differences supported a scenario where the four eulipotyphlan families diversified between 57.8 and 63.2 Ma. Given short branch lengths with low support values, traces of rampant genome-wide stochastic lineage sorting, and post K-Pg diversification, we concluded that the crown eulipotyphlan lineages arose through a rapid diversification after the K-Pg boundary when novel niches were created by the mass extinction of species.


Asunto(s)
Secuencia Conservada , Mamíferos/clasificación , Mamíferos/genética , Filogenia , Animales , Composición de Base/genética , Calibración , Secuencia Conservada/genética , Variación Genética , Funciones de Verosimilitud , Factores de Tiempo
4.
Mol Phylogenet Evol ; 121: 158-165, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29331683

RESUMEN

The mammalian order Eulipotyphla includes four extant families of insectivorans: Solenodontidae (solenodons); Talpidae (moles); Soricidae (shrews); and Erinaceidae (hedgehogs). Of these, Solenodontidae includes only two extant species, which are endemic to the largest islands of the Greater Antilles: Cuba and Hispaniola. Most molecular studies suggest that eulipotyphlan families diverged from each other across several million years, with the basal split between Solenodontidae and other families occurring in the Late Cretaceous. By contrast, Sato et al. (2016) suggest that eulipotyphlan families diverged from each other in a polytomy ∼58.6 million years ago (Mya). This more recent divergence estimate for Solenodontidae versus other extant eulipotyphlans suggests that solenodons must have arrived in the Greater Antilles via overwater dispersal rather than vicariance. Here, we show that the young timetree estimates for eulipotyphlan families and the polytomy are due to an inverted ingroup-outgroup arrangement of the tree, the result of using Tracer rather than TreeAnnotator to compile interfamilial divergence times, and of not enforcing the monophly of well-established clades such as Laurasiatheria and Eulipotyphla. Finally, Sato et al.'s (2016) timetree includes several zombie lineages where estimated divergence times are much younger than minimum ages that are implied by the fossil record. We reanalyzed Sato et al.'s (2016) original data with enforced monophyly for well-established clades and updated fossil calibrations that eliminate the inference of zombie lineages. Our resulting timetrees, which were compiled with TreeAnnotator rather than Tracer, produce dates that are in good agreement with other recent studies and place the basal split between Solenodontidae and other eulipotyphlans in the Late Cretaceous.


Asunto(s)
Fósiles , Mamíferos/clasificación , Filogenia , Animales , Calibración , Cuba , Evolución Molecular , Factores de Tiempo
6.
Front Neuroanat ; 18: 1452722, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39296922

RESUMEN

Many calcium-binding proteins are expressed in a region-and cell-type specific manner in the mammalian hippocampus. Neuronal calcium-binding proteins (NECABs) are also expressed in hippocampal neurons, but few species have been investigated, with partly controversial findings. We here describe NECAB1, NECAB2 and NECAB3 as well as parvalbumin, calbindin, and calretinin in the European mole, and compare staining patterns of these proteins with those in mouse and other species. While subtle differences are present, NECAB staining in the European mole was generally similar to those in mouse. Common to European moles, mice, and other species we investigated, large hilar polymorphic cells, likely to represent mossy cells, were positive for all three NECABs. NECAB1 and 2 are suitable as markers for these cells along the entire septotemporal axis of the hippocampus. In the European mole, parvalbumin, calbindin and calretinin showed traits that have been described in other species before, albeit in a unique combination. In summary, we provide the first description of distribution of these proteins in the hippocampus of the European mole. This subterranean, insectivorous, and solitary living species belongs to the Order of Eulipotyphla. Despite many similarities with other subterranean species from the rodent order in terms of lifestyle, its hippocampus is cytoarchitecturally much more elaborated than in, e.g., mole-rats. It remains an open question if the hippocampal structure of the European mole reflects evolutionary constraints or ecology. Our descriptive study highlights the diversity in hippocampal cytoarchitecture even in small mammalian species.

7.
Parasit Vectors ; 16(1): 392, 2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37898783

RESUMEN

BACKGROUND: Among hard ticks (Acari: Ixodidae), the genus Ixodes comprises the highest number of species, which in turn are most numerous in the Afrotropical zoogeographic region. In South Africa extensive morphological studies have been performed on Ixodes species but only few reports included molecular analyses. METHODS: In this study, 58 Ixodes spp. ticks, collected from ten mammalian and eight avian host species in South Africa, were molecularly and phylogenetically analyzed. In addition, a newly collected sample of the Palearctic Ixodes trianguliceps was included in the analyses. RESULTS: Among the ticks from South Africa, 11 species were identified morphologically. The majority of ticks from mammals represented the Ixodes pilosus group with two species (n = 20), followed by ticks resembling Ixodes rubicundus (n = 18) and Ixodes alluaudi (n = 3). In addition, single specimens of Ixodes rhabdomysae, Ixodes ugandanus, Ixodes nairobiensis and Ixodes simplex were also found. Considering bird-infesting ticks, Ixodes theilerae (n = 7), Ixodes uriae (n = 4) and ticks most similar to Ixodes daveyi (provisionally named I. cf. daveyi, n = 2) were identified. Molecular analyses confirmed two species in the I. pilosus group and a new species (I. cf. rubicundus) closely related to I. rubicundus sensu stricto. Phylogenetic trees based on concatenated mitochondrial or mitochondrial and nuclear gene sequences indicated that the subgenus Afrixodes forms a monophyletic clade with bird-associated exophilic ticks (subgenus Trichotoixodes). Ixodes trianguliceps clustered separately whereas I. alluaudi with their morphologically assigned subgenus, Exopalpiger. CONCLUSIONS: Phylogenetic analyses shed new lights on the relationships of Ixodes subgenera when including multiple sequences from subgenus Afrixodes and African as well as Palearctic species of subgenera Trichotoixodes and Exopalpiger. Subgenera Afrixodes and bird-associated Trichotoixodes share common ancestry, suggesting that the latter might have also originated in Africa. Regarding the subgenus Exopalpiger, I. alluaudi is properly assigned as it clusters among different Australian Ixodes, whereas I. trianguliceps should be excluded.


Asunto(s)
Ixodes , Ixodidae , Animales , Ixodes/genética , Filogenia , Sudáfrica , Australia , Ixodidae/genética , Aves , Mamíferos
8.
Biodivers Data J ; 11: e106256, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37476208

RESUMEN

Background: Of the 108 species that occur in Georgia, ten species are insectivores belonging to the order Eulipotyphla. Forty percent of them are endemic to the Caucasus and sixty percent are endemic to the Middle East, including the Caucasus. Up to now, no comprehensive data on the distribution of insectivores in Georgia have been available.The aggregated standardised data on the occurrence of small mammals can be applied to resource management, biogeography, ecological and systematic studies and to the planning of nature conservation efforts. Hereafter, the attempt to provide accumulated in one paper all known points of insectivores' occurrence in Georgia and make it available to researchers via the open repository GBIF is presented.The dataset is based on both literature data from 30 published sources (251 records), collection vouchers from four main zoological collections containing vouchers from Georgia (415 records) and authors' fieldwork results (217 records). The occurrence points of the specimens stored in collections and museums have been extracted from museum voucher labels and museum journals. New information: All known sampling points of insectivores in Georgia are collected in one dataset for the first time. Our field surveillance data reach about 24.6% of the records. Most of our data collected since 2003 have not been published yet. About 28.4% of the records have been recovered from publications in Russian and Georgian languages and 47% of the dataset records are derived from collections.

9.
J Parasitol ; 109(1): 21-26, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36808923

RESUMEN

The eastern mole, Scalopus aquaticus (L.), is a common inhabitant of loamy soils in Canada, the eastern United States, and Mexico. Seven coccidian parasites have been previously reported from S. aquaticus, including 3 cyclosporans and 4 eimerians from hosts taken in Arkansas and Texas. A single S. aquaticus, collected in February 2022 in central Arkansas, was found to be passing oocysts of 2 coccidians, a new species of Eimeria, and Cyclospora yatesiMcAllister, Motriuk-Smith, and Kerr, 2018. Oocysts of Eimeria brotheri n. sp. are ellipsoidal (sometimes ovoidal) with a smooth bilayered wall, measure 14.0 × 9.9 µm, and have a length/width (L/W) ratio of 1.5; both micropyle and oocyst residua are absent, but a single polar granule is present. Sporocysts are ellipsoidal and measure 8.1 × 4.6 µm, L/W 1.8; a flattened to knoblike Stieda body as well as a rounded sub-Stieda body are present. The sporocyst residuum is composed of an irregular mass of large granules. Additional metrical and morphological information is provided on oocysts of C. yatesi. This study demonstrates that although several coccidians were previously documented from this host, additional S. aquaticus should be examined for coccidians from Arkansas as well as other parts of its range.


Asunto(s)
Coccidiosis , Cyclospora , Eimeria , Animales , Eulipotyphla , Arkansas , Oocistos , Coccidiosis/parasitología , Heces/parasitología
10.
J Fungi (Basel) ; 9(2)2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36836334

RESUMEN

Pneumocystis spp. are thought to adapt to the lungs of potentially all mammals. However, the full host range, fungal burden and severity of infection are unknown for many species. In this study, lung tissue samples originating from 845 animals of 31 different families of eight mammal orders were screened by in situ hybridization (ISH) using a universal 18S rRNA probe for Pneumocystis, followed by hematoxylin and eosin (H&E) staining for determining histopathological lesions. A total of 216 (26%) samples were positive for Pneumocystis spp., encompassing 36 of 98 investigated mammal species, with 17 of them being described for the first time for the presence of Pneumocystis spp. The prevalence of Pneumocystis spp. as assessed by ISH varied greatly among different mammal species while the organism load was overall low, suggesting a status of colonization or subclinical infection. Severe Pneumocystis pneumonia seemed to be very rare. For most of the Pneumocystis-positive samples, comparative microscopic examination of H&E- and ISH-stained serial sections revealed an association of the fungus with minor lesions, consistent with an interstitial pneumonia. Colonization or subclinical infection of Pneumocystis in the lung might be important in many mammal species because the animals may serve as a reservoir.

11.
Vaccines (Basel) ; 10(7)2022 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-35891269

RESUMEN

The immune systems of all vertebrates contain cathelicidins, a family of antimicrobial peptides. Cathelicidins are a type of innate immune effector that have a number of biological functions, including a well-known direct antibacterial action and immunomodulatory function. In search of new templates for antimicrobial peptide discovery, we have identified and characterized the cathelicidin of the small mammal Talpa occidentalis. We describe the heterogeneity of cathelicidin in the order Eulipotyphla in relation to the Iberian mole and predict its antibacterial activity using bioinformatics tools. In an effort to correlate these findings, we derived the putative active peptide and performed in vitro hemolysis and antimicrobial activity assays, confirming that Iberian mole cathelicidins are antimicrobial. Our results showed that the Iberian mole putative peptide, named To-KL37 (KLFGKVGNLLQKGWQKIKNIGRRIKDFFRNIRPMQEA) has antibacterial and antifungal activity. Understanding the antimicrobial defense of insectivores may help scientists prevent the spread of pathogens to humans. We hope that this study can also provide new, effective antibacterial peptides for future drug development.

12.
Toxins (Basel) ; 14(12)2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36548740

RESUMEN

The evolution of venom and the selection pressures that act on toxins have been increasingly researched within toxinology in the last two decades, in part due to the exceptionally high rates of diversifying selection observed in animal toxins. In 2015, Sungar and Moran proposed the 'two-speed' model of toxin evolution linking evolutionary age of a group to the rates of selection acting on toxins but due to a lack of data, mammals were not included as less than 30 species of venomous mammal have been recorded, represented by elusive species which produce small amounts of venom. Due to advances in genomics and transcriptomics, the availability of toxin sequences from venomous mammals has been increasing. Using branch- and site-specific selection models, we present the rates of both episodic and pervasive selection acting upon venomous mammal toxins as a group for the first time. We identified seven toxin groups present within venomous mammals, representing Chiroptera, Eulipotyphla and Monotremata: KLK1, Plasminogen Activator, Desmallipins, PACAP, CRiSP, Kunitz Domain One and Kunitz Domain Two. All but one group (KLK1) was identified by our results to be evolving under both episodic and pervasive diversifying selection with four toxin groups having sites that were implicated in the fitness of the animal by TreeSAAP (Selection on Amino Acid Properties). Our results suggest that venomous mammal ecology, behaviour or genomic evolution are the main drivers of selection, although evolutionary age may still be a factor. Our conclusion from these results indicates that mammalian toxins are following the two-speed model of selection, evolving predominately under diversifying selection, fitting in with other younger venomous taxa like snakes and cone snails-with high amounts of accumulating mutations, leading to more novel adaptions in their toxins.


Asunto(s)
Quirópteros , Toxinas Biológicas , Animales , Toxinas Biológicas/genética , Toxinas Biológicas/toxicidad , Mamíferos/genética , Ponzoñas/genética , Ponzoñas/toxicidad , Serpientes , Perfilación de la Expresión Génica , Evolución Molecular
13.
Ecology ; 103(6): e3654, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35132618

RESUMEN

Mammals are threatened worldwide, with ~26% of all species being included in the IUCN threatened categories. This overall pattern is primarily associated with habitat loss or degradation, and human persecution for terrestrial mammals, and pollution, open net fishing, climate change, and prey depletion for marine mammals. Mammals play a key role in maintaining ecosystems functionality and resilience, and therefore information on their distribution is crucial to delineate and support conservation actions. MAMMALS IN PORTUGAL is a publicly available data set compiling unpublished georeferenced occurrence records of 92 terrestrial, volant, and marine mammals in mainland Portugal and archipelagos of the Azores and Madeira that includes 105,026 data entries between 1873 and 2021 (72% of the data occurring in 2000 and 2021). The methods used to collect the data were: live observations/captures (43%), sign surveys (35%), camera trapping (16%), bioacoustics surveys (4%) and radiotracking, and inquiries that represent less than 1% of the records. The data set includes 13 types of records: (1) burrows | soil mounds | tunnel, (2) capture, (3) colony, (4) dead animal | hair | skulls | jaws, (5) genetic confirmation, (6) inquiries, (7) observation of live animal (8), observation in shelters, (9) photo trapping | video, (10) predators diet | pellets | pine cones/nuts, (11) scat | track | ditch, (12) telemetry and (13) vocalization | echolocation. The spatial uncertainty of most records ranges between 0 and 100 m (76%). Rodentia (n =31,573) has the highest number of records followed by Chiroptera (n = 18,857), Carnivora (n = 18,594), Lagomorpha (n = 17,496), Cetartiodactyla (n = 11,568) and Eulipotyphla (n = 7008). The data set includes records of species classified by the IUCN as threatened (e.g., Oryctolagus cuniculus [n = 12,159], Monachus monachus [n = 1,512], and Lynx pardinus [n = 197]). We believe that this data set may stimulate the publication of other European countries data sets that would certainly contribute to ecology and conservation-related research, and therefore assisting on the development of more accurate and tailored conservation management strategies for each species. There are no copyright restrictions; please cite this data paper when the data are used in publications.


Asunto(s)
Carnívoros , Ecosistema , Animales , Cambio Climático , Mamíferos , Portugal , Conejos , Roedores
14.
Microbiol Spectr ; 10(5): e0130622, 2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36169417

RESUMEN

Orthohantaviruses (genus Orthohantavirus) are a diverse group of viruses that are closely associated with their natural hosts (rodents, shrews, and moles). Several orthohantaviruses cause severe disease in humans. Central and western Europe are areas with emerging orthohantavirus occurrences. In our study, several orthohantaviruses, including the pathogenic Kurkino virus (KURV), were detected in their natural hosts trapped at several study sites in the Czech Republic. KURV was detected mainly in its typical host, the striped field mouse (Apodemus agrarius). Nevertheless, spillover infections were also detected in wood mice (Apodemus sylvaticus) and common voles (Microtus arvalis). Similarly, Tula virus (TULV) was found primarily in common voles, and events of spillover to rodents of other host species, including Apodemus spp., were recorded. In addition, unlike most previous studies, different tissues were sampled and compared to assess their suitability for orthohantavirus screening and possible tissue tropism. Our data suggest possible virus-specific tissue tropism in rodent hosts. TULV was most commonly detected in the lung tissue, whereas KURV was more common in the liver, spleen, and brain. Moreover, Seewis and Asikkala viruses were detected in randomly found common shrews (Sorex araneus). In conclusion, we have demonstrated the presence of human-pathogenic KURV and the potentially pathogenic TULV in their typical hosts as well as their spillover to atypical host species belonging to another family. Furthermore, we suggest the possibility of virus-specific tissue tropism of orthohantaviruses in their natural hosts. IMPORTANCE Orthohantaviruses (genus Orthohantavirus, family Hantaviridae) are a diverse group of globally distributed viruses that are closely associated with their natural hosts. Some orthohantaviruses are capable of infecting humans and causing severe disease. Orthohantaviruses are considered emerging pathogens due to their ever-increasing diversity and increasing numbers of disease cases. We report the detection of four different orthohantaviruses in rodents and shrews in the Czech Republic. Most viruses were found in their typical hosts, Kurkino virus (KURV) in striped field mice (Apodemus agrarius), Tula virus (TULV) in common voles (Microtus arvalis), and Seewis virus in common shrews (Sorex araneus). Nevertheless, spillover infections of atypical host species were also recorded for KURV, TULV, and another shrew-borne orthohantavirus, Asikkala virus. In addition, indications of virus-specific patterns of tissue tropism were observed. Our results highlight the circulation of several orthohantaviruses, including KURV, which is pathogenic to humans, among rodents and shrews in the Czech Republic.


Asunto(s)
Infecciones por Hantavirus , Orthohantavirus , Animales , Humanos , Ratones , Infecciones por Hantavirus/epidemiología , Infecciones por Hantavirus/veterinaria , Musarañas , República Checa/epidemiología , Filogenia , Arvicolinae , Murinae , Tropismo
15.
Elife ; 102021 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-33949308

RESUMEN

The speciose mammalian order Eulipotyphla (moles, shrews, hedgehogs, solenodons) combines an unusual diversity of semi-aquatic, semi-fossorial, and fossorial forms that arose from terrestrial forbearers. However, our understanding of the ecomorphological pathways leading to these lifestyles has been confounded by a fragmentary fossil record, unresolved phylogenetic relationships, and potential morphological convergence, calling for novel approaches. The net surface charge of the oxygen-storing muscle protein myoglobin (ZMb), which can be readily determined from its primary structure, provides an objective target to address this question due to mechanistic linkages with myoglobin concentration. Here, we generate a comprehensive 71 species molecular phylogeny that resolves previously intractable intra-family relationships and then ancestrally reconstruct ZMb evolution to identify ancient lifestyle transitions based on protein sequence alone. Our phylogenetically informed analyses confidently resolve fossorial habits having evolved twice in talpid moles and reveal five independent secondary aquatic transitions in the order housing the world's smallest endothermic divers.


The shrews, moles and hedgehogs that surround us all belong to the same large group of insect-eating mammals. While most members in this 'Eulipotyphla order' trot on land, some, like moles, have evolved to hunt their prey underground. A few species, such as the water shrews, have even ventured to adopt a semi-aquatic lifestyle, diving into ponds and streams to retrieve insects. These underwater foragers share unique challenges, burning a lot of energy and losing heat at a high rate while not being able to store much oxygen. It is still unclear how these semi-aquatic habits have come to be: the fossil record is fragmented and several species tend to display the same adaptations even though they have evolved separately. This makes it difficult to identify when and how many times the Eulipotyphla species started to inhabit water. The protein myoglobin, which gives muscles their red color, could help in this effort. This molecule helps muscles to capture oxygen from blood, a necessary step for cells to obtain energy. Penguins, seals and whales, which dive to get their food, often have much higher concentration of myoglobin so they can spend extended amount of time without having to surface for air. In addition, previous work has shown that eight groups of mammalian divers carry genetic changes that help newly synthetized myoglobin proteins to not stick to each other. This means that these animals can store more of the molecule in their muscles, increasing their oxygen intake and delivery. He et al. therefore speculated that all semi-aquatic Eulipotyphla species would carry genetic changes that made their myoglobin less likely to clump together; underground species, which also benefit from absorbing more oxygen, would display intermediate alterations. In addition, reconstructing the myoglobin sequences from the ancestors of living species would help to spot when the transition to aquatic life took place. A variety of approaches were harnessed to obtain myoglobin and other sequences from 55 eulipotyphlan mammals, which then were used to construct a strongly supported family tree for this group. The myoglobin results revealed that from terrestrial to subterranean to semi-aquatic species, genetic changes took place that would diminish the ability for the proteins to stick to each other. This pattern also showed that semi-aquatic lifestyles have independently evolved five separate times ­ twice in moles, three times in shrews. By retracing the evolutionary history of specific myoglobin properties, He et al. shed light on how one of the largest orders of mammals has come to be fantastically diverse.


Asunto(s)
Organismos Acuáticos/fisiología , Mamíferos/fisiología , Mioglobina/química , Mioglobina/genética , Filogenia , Secuencia de Aminoácidos , Animales , Organismos Acuáticos/química , Organismos Acuáticos/genética , ADN/genética , Evolución Molecular , Fósiles , Mamíferos/genética , Topos , Mioglobina/clasificación , Mioglobina/metabolismo , Oxígeno
16.
Ticks Tick Borne Dis ; 12(4): 101715, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33819744

RESUMEN

Three Palearctic members of the subgenus Pholeoixodes, i.e., Ixodes canisuga, Ixodes hexagonus and Ixodes kaiseri are frequently collected from dogs, cats, red foxes, badgers and other carnivorous/insectivorous hosts in Europe. While a pictorial identification key has been reported for female Pholeoixodes ticks, a similar work has not been done on their male, nymphal and larval specimens. This study was initiated in order to clarify and re-examine those morphological characters of these three tick species, which can be used relatively easily to identify/distinguish them. In the case of larvae the aims included finding alternatives to chaetotaxy, which is difficult to observe and its usefulness is also affected by uncertainties in literature data. For this, 609 Pholeoixodes ticks (males, nymphs and larvae) were collected from carnivores, hedgehogs and their environment in six European countries (representing Western, Central and Southeastern Europe), followed by detailed morphological examination and/or molecular analyses to confirm the identity of their species. Based on the morphology of 84 molecularly analyzed specimens and a new identification key compiled accordingly, altogether 116 I. canisuga, 277 I. hexagonus and 216 I. kaiseri males, nymphs and larvae were identified. Ixodes kaiseri was not found in Western Europe, where I. canisuga predominated. In Central Europe, all three Pholeoixodes species were collected, the largest number of specimens represented by I. hexagonus. On the other hand, in Southeastern Europe I. kaiseri had the highest abundance. In conclusion, the morphology of internal spur on the first coxae (as the traditionally used character to distinguish I. hexagonus from other Pholeoixodes species) is trustworthy to recognize males but is less informative in the case of nymphs and larvae. The latter can be identified more properly by observing the morphology of basis capituli. In particular, nymphs and larvae of I. canisuga have anteriorly flattened basis capituli, forming a plateau that surrounds the base of the hypostome. On the other hand, nymphs and larvae of I. hexagonus and I. kaiseri lack a similar plateau, but (unlike I. canisuga) have cornuae, which are either posterolaterally or caudally directed, respectively.


Asunto(s)
Clasificación/métodos , Ixodidae/anatomía & histología , África del Norte , Animales , Europa (Continente) , Ixodidae/clasificación , Ixodidae/crecimiento & desarrollo , Larva/anatomía & histología , Larva/clasificación , Larva/crecimiento & desarrollo , Masculino , Medio Oriente , Ninfa/anatomía & histología , Ninfa/clasificación , Ninfa/crecimiento & desarrollo , Especificidad de la Especie
17.
Zootaxa ; 4809(2): zootaxa.4809.2.11, 2020 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-33055944

RESUMEN

The Flora and Fauna Protection Area (Área de Protección de Flora y Fauna-ÁPFF) Cerro del Mohinora, is the highest mountain in northern Mexico, reaching an elevation of 3,300 meters. It constitutes one of the last high-elevation islands of alpine and subalpine vegetation known in the Sierra Madre Occidental, in the extreme southwestern part of Chihuahua. The ÁPFF Cerro del Mohinora is located near the state border and limits with Durango and Sinaloa. This type of ecosystem located at high altitudes is in danger of disappearing since only 1% or less of its original extension remains; it is considered a refuge for species with boreal affinities (McDonald et al. 2011).


Asunto(s)
Musarañas , Animales , Ecosistema , México , Prevalencia
18.
Anat Sci Int ; 95(3): 313-322, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31933048

RESUMEN

The tongue of the lesser hedgehog tenrec (Echinops telfairi) was evaluated by light and scanning electron microscopy. Dorsal and lateral surfaces of the tongue were densely covered with various types of lingual papillae. Two types of mechanical papillae (filiform and conical) and two types of sensory papillae (fungiform and vallate) were observed. Rostrocaudally, the number of spikes in filiform papillae increased. Filiform, crown-like papillae were found on the radix, as well as large conical papillae with a wide base and a caudally bent single spike. Fungiform papillae were scattered in four rows on the dorsal surface. Three vallate papillae in inverse triangular layout were developed in the area of the lingual radix. Taste buds were found in the sensory papillae, i.e., fungiform and vallate. The lingual glands were predominantly seromucous. These glands were evenly scattered from the caudal portion of the lingual apex to the lingual radix. Purely serous glands were localized close to vallate papillae. A histochemical analysis of glands was performed. Results were compared to the Afrotheria (tenrec's relatives) and Eulipotyphla (animals with similar feeding habits to tenrecs). This study is the first description of the lingual morphology in the member of the Order Afrosoricida. Moreover, it compares the effect of the phylogenetic relation to the effect of the feeding habits on the lingual morphology.


Asunto(s)
Erizos/anatomía & histología , Lengua/ultraestructura , Animales , Microscopía Electrónica de Rastreo
19.
Acta Histochem ; 122(3): 151515, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32081447

RESUMEN

Most mammalian species have a vomeronasal organ that detects specific chemical substances, such as pheromones. Mucous fluid covering the vomeronasal sensory epithelium is secreted by vomeronasal glands, and the properties of these fluids have been suggested to be involved in chemical detection. Histological studies using periodic acid-Schiff (PAS) and Alcian blue pH 2.5 (AB) stains, which respectively detect natural and acidic polysaccharides, have suggested variations in the nature of the vomeronasal glands among species. Here, we investigated the responsivity of the vomeronasal glands to PAS and AB stains in eight Laurasiatheria species. All species studied herein possessed vomeronasal glands that stained positive for PAS, like other many reported species. The vomeronasal glands of dogs and minks - like rodents, were AB-negative, whereas those of cows, goats, sika deer, musk shrews and two bat species were positive. Considering the present findings and previous reports, the vomeronasal glands in most of Laurasiatheria species appear to be fundamentally abundant in acidic polysaccharides, whereas those in carnivores essentially contains neutral polysaccharides.


Asunto(s)
Mamíferos/metabolismo , Polisacáridos/metabolismo , Órgano Vomeronasal/metabolismo , Azul Alcián , Animales , Bovinos , Quirópteros , Ciervos , Perros , Ratones Endogámicos ICR , Visón , Bulbo Olfatorio , Reacción del Ácido Peryódico de Schiff , Polisacáridos/química , Musarañas
20.
Viruses ; 12(12)2020 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-33419245

RESUMEN

Due to their need for living cells, viruses have developed adaptive evolutionary strategies to survive and perpetuate in reservoir hosts that play a crucial role in the ecology of emerging pathogens. Pathogenic and potentially pandemic betacoronaviruses arose in humans in 2002 (SARS-CoV, disappeared in July 2003), 2012 (MERS-CoV, still circulating in Middle East areas), and 2019 (SARS-CoV-2, causing the current global pandemic). As universally recognized, bats host ancestors of the above-mentioned zoonotic viruses. However, hedgehogs have been recently identified in Europe and Asia as possible reservoirs of MERS-CoV-like strains classified as Erinaceus coronavirus (EriCoV). To elucidate the evolution and genetics of EriCoVs, NGS (next generation sequencing) and Sanger sequencing were used to examine fecal samples collected in Northern Italy in 2018/2019 from 12 hedgehogs previously found EriCoV-positive by RT-PCR. By sequence analysis, eight complete EriCoV genomes, obtained by NGS, showed a high phylogenetic correlation with EriCoV strains previously reported in Eurasia. Interestingly, eight viral strains presented an additional ORF encoding for the CD200 ortholog located between the genes encoding for the Spike and the ORF3a proteins. The CD200 ortholog sequences were closely similar to the host CD200 protein but varying among EriCoVs. The result, confirmed by Sanger sequencing, demonstrates for the first time that CoVs can acquire host genes potentially involved in the immune-modulatory cascade and possibly enabling the virus to escape the host defence.


Asunto(s)
Infecciones por Coronavirus/virología , Coronavirus/clasificación , Coronavirus/genética , Erizos/virología , Animales , Composición de Base , Betacoronavirus/clasificación , Betacoronavirus/genética , COVID-19/virología , Quirópteros/virología , Evolución Molecular , Genoma Viral , Coronavirus del Síndrome Respiratorio de Oriente Medio/genética , Pandemias , Filogenia , SARS-CoV-2/genética , Alineación de Secuencia , Análisis de Secuencia , Glicoproteína de la Espiga del Coronavirus/genética
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda