Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 50
Filtrar
1.
Commun Biol ; 7(1): 792, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38951693

RESUMEN

The African buffalo (Syncerus caffer) is a wild bovid with a historical distribution across much of sub-Saharan Africa. Genomic analysis can provide insights into the evolutionary history of the species, and the key selective pressures shaping populations, including assessment of population level differentiation, population fragmentation, and population genetic structure. In this study we generated the highest quality de novo genome assembly (2.65 Gb, scaffold N50 69.17 Mb) of African buffalo to date, and sequenced a further 195 genomes from across the species distribution. Principal component and admixture analyses provided little support for the currently described four subspecies. Estimating Effective Migration Surfaces analysis suggested that geographical barriers have played a significant role in shaping gene flow and the population structure. Estimated effective population sizes indicated a substantial drop occurring in all populations 5-10,000 years ago, coinciding with the increase in human populations. Finally, signatures of selection were enriched for key genes associated with the immune response, suggesting infectious disease exert a substantial selective pressure upon the African buffalo. These findings have important implications for understanding bovid evolution, buffalo conservation and population management.


Asunto(s)
Búfalos , Genoma , Genómica , Búfalos/genética , Animales , Genómica/métodos , Flujo Génico , África del Sur del Sahara , Genética de Población , Filogenia , Variación Genética
2.
PLoS One ; 19(5): e0302028, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38718094

RESUMEN

Determining the dietary spectrum of European insectivorous bats over time is the cornerstone of their conservation, as it will aid our understanding of foraging behavior plasticity in response to plummeting insect populations. Despite the global decline in insects, a restricted number of arthropod pest species thrive. Yet past research has overlooked the potential of European bats to suppress pests harmful to woodlands or livestock, in spite of their economic relevance. Here we investigated the diet composition, its breeding season variations and pest consumption of an insectivorous bat species (Myotis emarginatus), at the northern edge of its range (Wallonia, Belgium). We also explored the prey ecology to gain insight into the hunting strategies and foraging habitats of this bat species. We used DNA metabarcoding to amplify two COI markers within 195 bat droppings collected in June, July and August, thereby identifying 512 prey taxa predominated by Diptera, Araneae and Lepidoptera. Overall, in 97% of the samples we detected at least one of the 58 potential pest taxa, 41 of which targeting trees. The June samples were marked by a diet rich in orb-weaver spiders, in accordance with the archetypal diet of M. emarginatus bats. However, during the highly energy demanding July-August parturition and lactation period, roughly 55% of the dropping samples contained two cattle fly pests (Stomoxys calcitrans and Musca domestica). Moreover, among the 88 Diptera species preyed upon by M. emarginatus in July and August, these flies accounted for around 50% of the taxa occurrences. This plasticity-the switch from a spider-rich to a fly-rich diet-seems providential considering the dramatic ongoing drop in insect populations but this involves ensuring bat-friendly cattle farming. Our results revealed that bats widely consume pest entomofauna, thereby highlighting their potential role as allies of forest managers and farmers.


Asunto(s)
Quirópteros , Conducta Predatoria , Arañas , Animales , Quirópteros/parasitología , Quirópteros/fisiología , Bovinos , Arañas/fisiología , Conducta Alimentaria , Estaciones del Año , Dieta , Dípteros/fisiología , Bélgica , Ecosistema
3.
Int Microbiol ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589705

RESUMEN

The microbiome is an important consideration for the conservation of endangered species. Studies provided evidence of the effect of behavior and habitat change on the microbiota of wild animals and reported various inferences. It indicates the complexity of factors influencing microbiota diversity, including incomplete sampling procedures. Data abnormality may arise due to the procedures warranting preliminary analysis, such as rarefaction, before downstream analysis. This present study demonstrated the effect of data rarefaction and aggregation on the comparison of wild rusa deer's gut microbial diversity. Eighty-five feces samples were collected from 11 deer populations inhabiting three national parks in Java and Bali islands. Using the Illumina Nova-Seq platform, fragments of 16s rRNA gene were sequenced, and raw data of 51,389 reads corresponding to 2 domains, 22 phyla, 45 classes, 83 orders, 182 families, and 460 genera of bacteria were obtained. Data rarefaction was applied at two different library sizes (minimum and fixed) and aggregation (11 populations into 3 research sites) to investigate its effect on the microbial diversity comparison. There are significant differences in alpha diversity between populations, but not research sites, at all library sizes of rarefaction. A similar finding is also found in beta diversity. Moreover, data rarefaction and aggregation result in different values of the diversity metrics. This present study shows that statistical analysis remains a substantial concern in microbiome studies applied to conservation biology. It suggests reporting a more detailed data normalization in microbiome studies as an inherent control of suboptimal sampling, particularly when involving feces.

4.
Ecol Evol ; 13(12): e10788, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38077514

RESUMEN

DNA from the environment (eDNA) has been increasingly used as a new tool to conduct biodiversity assessment. Because of its noninvasive and less time-consuming nature, many studies of recent years solely rely on this information to establish a species inventory. eDNA metabarcoding has been shown to be an efficient method in aquatic ecosystems, especially for fish. However, detection efficiency is not clear for mammals. Using the existing literature, we conducted a meta-analysis to investigate if eDNA metabarcoding allows greater detection success compared to conventional surveys (such as field surveys, camera traps, etc.). Although only 28 articles were retrieved, showing the lack of comparative studies, still representing more than 900 taxa detected, we found that detection success was method dependent, but most importantly varies on the taxonomy of the targeted taxa. eDNA metabarcoding performed poorly for bats compared to the traditional mist nests. However, strong detection overlaps were found between conventional surveys and eDNA for large-bodied mammals such as ungulates, primates, and carnivores. Overall, we argue that using both molecular and field approaches can complement each other and can maximize the most accurate biodiversity assessment and there is much room for metabarcoding optimization to reach their full potential compared to traditional surveys.

5.
Infect Ecol Epidemiol ; 13(1): 2270258, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37867606

RESUMEN

The alpine ecosystems and communities of central Asia are currently undergoing large-scale ecological and socio-ecological changes likely to affect wildlife-livestock-human disease interactions and zoonosis transmission risk. However, relatively little is known about the prevalence of pathogens in this region. Between 2012 and 2015 we screened 142 rodents in Mongolia's Gobi desert for exposure to important zoonotic and livestock pathogens. Rodent seroprevalence to Leptospira spp. was >1/3 of tested animals, Toxoplasma gondii and Coxiella burnetii approximately 1/8 animals, and the hantaviruses being between 1/20 (Puumala-like hantavirus) and <1/100 (Seoul-like hantavirus). Gerbils trapped inside local dwellings were one of the species seropositive to Puumala-like hantavirus, suggesting a potential zoonotic transmission pathway. Seventeen genera of zoonotic bacteria were also detected in the faeces and ticks collected from these rodents, with one tick testing positive to Yersinia. Our study helps provide baseline patterns of disease prevalence needed to infer potential transmission between source and target populations in this region, and to help shift the focus of epidemiological research towards understanding disease transmission among species and proactive disease mitigation strategies within a broader One Health framework.

6.
J Hered ; 113(5): 500-515, 2022 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-35932226

RESUMEN

The European polecat (Mustela putorius) is a mammalian predator which occurs across much of Europe east to the Ural Mountains. In Great Britain, following years of persecution the range of the European polecat contracted and by the early 1900s was restricted to unmanaged forests of central Wales. The European polecat has recently undergone a population increase due to legal protection and its range now overlaps that of feral domestic ferrets (Mustela putorius furo). During this range expansion, European polecats hybridized with feral domestic ferrets producing viable offspring. Here, we carry out population-level whole-genome sequencing on 8 domestic ferrets, 19 British European polecats, and 15 European polecats from the European mainland. We used a range of population genomics methods to examine the data, including phylogenetics, phylogenetic graphs, model-based clustering, phylogenetic invariants, ABBA-BABA tests, topology weighting, and Fst. We found high degrees of genome introgression in British polecats outside their previous stronghold, even in those individuals phenotyped as "pure" polecats. These polecats ranged from presumed F1 hybrids (gamma = 0.53) to individuals that were much less introgressed (gamma = 0.2). We quantify this introgression and find introgressed genes containing Fst outliers associated with cognitive function and sight.


Asunto(s)
Hurones , Humanos , Animales , Hurones/genética , Reino Unido , Filogenia , Europa (Continente) , Fenotipo
7.
Genes (Basel) ; 12(10)2021 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-34680950

RESUMEN

Although properly designed sampling in population genetic studies is of key importance for planning evidence-informed conservation measures, sampling strategies are rarely discussed. This is the case for the European mink Mustela lutreola, a critically endangered species. In order to address this problem, a meta-analysis aiming to examine the completeness of mtDNA haplotype sampling in recent studies of M. lutreola inter-population genetic diversity was conducted. The analysis was performed using the sample-size-based rarefaction and extrapolation sampling curve method for three populations-the Northeastern (Russia, Belarus and Estonia), the Western (France and Spain), and the Southeastern (Romania). The extrapolated values of the Shannon-Wiener index were determined, assuming full sample coverage. The gap between the measured and predicted inter-population genetic diversity was estimated, indicating that the identified level of sample coverage was the lowest for the NE population (87%), followed by the SE population (96%) and the W population (99%). A guide for sampling design and accounting for sampling uncertainty in future population genetic studies on European mink is provided. The relatively low sample coverage for the Russian population clearly indicates an urgent need to take conservation measures for European mink in this country.


Asunto(s)
Especies en Peligro de Extinción , Visón/genética , Polimorfismo Genético , Animales , ADN Mitocondrial/genética , Ecosistema , Modelos Genéticos
8.
Mol Ecol ; 30(18): 4584-4600, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34245618

RESUMEN

Ecological theory postulates that niches of co-occurring species must differ along some ecological dimensions in order to allow their stable coexistence. Yet, many biological systems challenge this competitive exclusion principle. Insectivorous bats from the Northern Hemisphere typically form local assemblages of multiple species sharing highly similar functional traits and pertaining to identical feeding guilds. Although their trophic niche can be accessed with unprecedented details using genetic identification of prey, the underlying mechanisms of resource partitioning remain vastly unexplored. Here, we studied the differential diet of three closely-related bat species of the genus Plecotus in sympatry and throughout their entire breeding season using DNA metabarcoding. Even at such a small geographic scale, we identified strong seasonal and spatial variation of their diet composition at both intra- and interspecific levels. Indeed, while the different bats fed on a distinct array of prey during spring, they showed higher trophic niche overlap during summer and fall, when all three species switched their hunting behaviour to feed on few temporarily abundant moths. By recovering 19 ecological traits for over 600 prey species, we further inferred that each bat species used different feeding grounds and hunting techniques, suggesting that niche partitioning was primarily habitat-driven. The two most-closely related bat species exhibited very distinct foraging habitat preferences, while the third, more distantly-related species was more generalist. These results highlight the need of temporally comprehensive samples to fully understand species coexistence, and that valuable information can be derived from the taxonomic identity of prey obtained by metabarcoding approaches.


Asunto(s)
Quirópteros , Mariposas Nocturnas , Animales , Quirópteros/genética , Código de Barras del ADN Taxonómico , Conducta Alimentaria , Hábitos , Conducta Predatoria
9.
Infect Genet Evol ; 93: 104978, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34175480

RESUMEN

Pneumocystis fungi are opportunistic parasites of mammalian lungs whose evolution, ecology and host specificity in natural host populations remain poorly understood and controversial. Using an extensive collection of 731 lung samples from 27 rodent species sampled in five Southeast Asian countries, and nested PCR amplification of mitochondrial and nuclear genes, we investigated the host specificity and genetic structure of Pneumocystis lineages infecting wild rodents. We also identified the rodent species playing a central role in the transmission of these parasites using network analysis and centrality measurement and we characterized the environmental conditions allowing Pneumocystis infection in Southeast Asia using generalized linear mixed models. Building upon an unprecedented Pneumocystis sampling from numerous rodent species belonging to closely related genera, our findings provide compelling evidence that the host specificity of Pneumocystis lineages infecting rodents is not restricted to a single host species or genus as often presented in the literature but it encompasses much higher taxonomic levels and more distantly related rodent host species. The phylogenetic species status at both mitochondrial and nuclear genetic markers of at least three new Pneumocystis lineages, highly divergent from Pneumocystis species currently described, is also suggested by our data. Our models show that the probability of Pneumocystis infection in rodent hosts is positively correlated to environmental variables reflecting habitat fragmentation and landscape patchiness. Synanthropic and habitat-generalist rodents belonging to the Rattus, Sundamys and Bandicota genera played a role of bridge host species for Pneumocystis spreading in these heterogeneous habitats, where they can reach high population densities. These are critical findings improving our understanding of the ecology of these enigmatic parasites and the role played by cospeciation and host switches in their evolution. Our results also confirmed the role of land-use change and habitat fragmentation in parasite amplification and spillover in rodents.


Asunto(s)
Murinae , Infecciones por Pneumocystis/veterinaria , Pneumocystis/fisiología , Enfermedades de los Roedores/epidemiología , Enfermedades de los Roedores/transmisión , Animales , Animales Salvajes , Cambodia/epidemiología , Especificidad del Huésped , Laos/epidemiología , Filipinas/epidemiología , Infecciones por Pneumocystis/epidemiología , Infecciones por Pneumocystis/microbiología , Infecciones por Pneumocystis/transmisión , Enfermedades de los Roedores/microbiología , Taiwán/epidemiología , Tailandia/epidemiología
10.
mSystems ; 6(2)2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33850039

RESUMEN

Host-adapted microorganisms are generally assumed to have evolved from free-living, environmental microorganisms, as examples of the reverse process are rare. In the phylum Gammaproteobacteria, family Moraxellaceae, the genus Psychrobacter includes strains from a broad ecological distribution including animal bodies as well as sea ice and other nonhost environments. To elucidate the relationship between these ecological niches and Psychrobacter's evolutionary history, we performed tandem genomic analyses with phenotyping of 85 Psychrobacter accessions. Phylogenomic analysis of the family Moraxellaceae reveals that basal members of the Psychrobacter clade are Moraxella spp., a group of often-pathogenic organisms. Psychrobacter exhibited two broad growth patterns in our phenotypic screen: one group that we called the "flexible ecotype" (FE) had the ability to grow between 4 and 37°C, and the other, which we called the "restricted ecotype" (RE), could grow between 4 and 25°C. The FE group includes phylogenetically basal strains, and FE strains exhibit increased transposon copy numbers, smaller genomes, and a higher likelihood to be bile salt resistant. The RE group contains only phylogenetically derived strains and has increased proportions of lipid metabolism and biofilm formation genes, functions that are adaptive to cold stress. In a 16S rRNA gene survey of polar bear fecal samples, we detect both FE and RE strains, but in in vivo colonizations of gnotobiotic mice, only FE strains persist. Our results indicate the ability to grow at 37°C, seemingly necessary for mammalian gut colonization, is an ancestral trait for Psychrobacter, which likely evolved from a pathobiont.IMPORTANCE Host-associated microbes are generally assumed to have evolved from free-living ones. The evolutionary transition of microbes in the opposite direction, from host associated toward free living, has been predicted based on phylogenetic data but not studied in depth. Here, we provide evidence that the genus Psychrobacter, particularly well known for inhabiting low-temperature, high-salt environments such as sea ice, permafrost soils, and frozen foodstuffs, has evolved from a mammalian-associated ancestor. We show that some Psychrobacter strains retain seemingly ancestral genomic and phenotypic traits that correspond with host association while others have diverged to psychrotrophic or psychrophilic lifestyles.

11.
Viruses ; 11(12)2019 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-31795197

RESUMEN

Viruses belonging to the Dicistroviridae family have attracted a great deal of attention from scientists owing to their negative impact on agricultural economics, as well as their recent identification as potential aetiological agents of febrile illness in human patients. On the other hand, some Dicistroviruses are also studied for their potential biopesticide properties. To date, Dicistrovirus characterized in African mainland remain scarce. By using High-Throughput Sequencing technology on insectivorous bat faeces (Hipposideros Caffer) sampled in a cave used by humans to collect bat guano (bat manure) as fertilizer in Zimbabwe, we characterized the full-length sequences of three Dicistrovirus belonging to the Cripavirus and Aparavirus genus: Big Sioux River Virus-Like (BSRV-Like), Acute Bee Paralysis Virus (ABPV), and Aphid Lethal Paralysis Virus (ALPV). Phylogenetic analyses of ORF-1 and ORF-2 genes showed a complex evolutionary history between BSRV and close viruses, as well as for the Aparavirus genus. Herewith, we provide the first evidence of the presence of Dicistrovirus in Zimbabwe and highlight the need to further document the impact of such viruses on crops, as well as in beekeeping activities in Zimbabwe which represent a crucial source of income for Zimbabwean people.


Asunto(s)
Quirópteros/virología , Productos Agrícolas/virología , Dicistroviridae/genética , Agricultura , Animales , Evolución Biológica , Dicistroviridae/aislamiento & purificación , Heces/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Filogenia , Análisis de Secuencia de ARN , Zimbabwe
12.
PLoS One ; 14(7): e0219135, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31276547

RESUMEN

Metabarcoding of feces has revolutionized the knowledge of animal diets by providing unprecedented resolution of consumed resources. However, it is still unclear how different methodological approaches influence the ecological conclusions that can be drawn from such data. Here, we propose a critical evaluation of several data treatments on the inferred diet of the bat Plecotus auritus using guano regularly collected from various colonies throughout the entire active season. First and unlike previous claims, our data indicates that DNA extracted from large amounts of fecal material issued from guano accumulates yield broader taxonomic diversity of prey than smaller numbers of pellets would do, provided that extraction buffer volumes are adapted to such increased amounts of material. Second, trophic niche analyses based on prey occurrence data uncover strong seasonality in the bat's diet and major differences among neighboring maternity colonies. Third, while the removal of rare prey items is not always warranted as it introduces biases affecting particularly samples with greater prey species richness. Fourth, examination of distinct taxonomic depths in diet analyses highlights different aspects of food consumption providing a better understanding of the consumer's diet. Finally, the biologically meaningful patterns recovered with presence-absence approaches are virtually lost when attempting to quantify prey consumed using relative read abundances. Even in an ideal situation where reference barcodes are available for most potential prey species, inferring realistic patterns of prey consumption remains relatively challenging. Although best practice in metabarcoding analyses will depend on the aims of the study, several previous methodological recommendations seem unwarranted for studying such diverse diets as that of brown long-eared bats.


Asunto(s)
Alimentación Animal/análisis , Quirópteros/fisiología , Código de Barras del ADN Taxonómico/métodos , Heces/química , Animales , ADN/genética , Conducta Alimentaria , Secuenciación de Nucleótidos de Alto Rendimiento , Conducta Predatoria , Análisis de Secuencia de ADN
13.
Infect Ecol Epidemiol ; 9(1): 1604063, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31231481

RESUMEN

Background: Snow leopards, Panthera uncia, are a threatened apex predator, scattered across the mountains of Central and South Asia. Disease threats to wild snow leopards have not been investigated.Methods and Results: Between 2008 and 2015, twenty snow leopards in the South Gobi desert of Mongolia were captured and immobilised for health screening and radio-collaring. Blood samples and external parasites were collected for pathogen analyses using enzyme-linked immunosorbent assay (ELISA), microscopic agglutination test (MAT), and next-generation sequencing (NGS) techniques. The animals showed no clinical signs of disease, however, serum antibodies to significant zoonotic pathogens were detected. These pathogens included, Coxiella burnetii, (25% prevalence), Leptospira spp., (20%), and Toxoplasma gondii (20%). Ticks collected from snow leopards contained potentially zoonotic bacteria from the genera Bacillus, Bacteroides, Campylobacter, Coxiella, Rickettsia, Staphylococcus and Streptococcus.Conclusions: The zoonotic pathogens identified in this study, in the short-term did not appear to cause illness in the snow leopards, but have caused illness in other wild felids. Therefore, surveillance for pathogens should be implemented to monitor for potential longer- term disease impacts on this snow leopard population.

14.
PLoS One ; 13(11): e0205395, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30403704

RESUMEN

The African lion (Panthera leo), listed as a vulnerable species on the IUCN Red List of Threatened Species (Appendix II of CITES), is mainly impacted by indiscriminate killing and prey base depletion. Additionally, habitat loss by land degradation and conversion has led to the isolation of some subpopulations, potentially decreasing gene flow and increasing inbreeding depression risks. Genetic drift resulting from weakened connectivity between strongholds can affect the genetic health of the species. In the present study, we investigated the evolutionary history of the species at different spatiotemporal scales. Therefore, the mitochondrial cytochrome b gene (N = 128), 11 microsatellites (N = 103) and 9,103 SNPs (N = 66) were investigated in the present study, including a large sampling from Tanzania, which hosts the largest lion population among all African lion range countries. Our results add support that the species is structured into two lineages at the continental scale (West-Central vs East-Southern), underlining the importance of reviewing the taxonomic status of the African lion. Moreover, SNPs led to the identification of three lion clusters in Tanzania, whose geographical distributions are in the northern, southern and western regions. Furthermore, Tanzanian lion populations were shown to display good levels of genetic diversity with limited signs of inbreeding. However, their population sizes seem to have gradually decreased in recent decades. The highlighted Tanzanian African lion population genetic differentiation appears to have resulted from the combined effects of anthropogenic pressure and environmental/climatic factors, as further discussed.


Asunto(s)
Biodiversidad , Genética de Población , Estudio de Asociación del Genoma Completo , Leones/clasificación , Leones/genética , Alelos , Análisis de Varianza , Animales , Biología Computacional , Genes Mitocondriales , Variación Genética , Geografía , Secuenciación de Nucleótidos de Alto Rendimiento , Repeticiones de Microsatélite , Polimorfismo de Nucleótido Simple , Dinámica Poblacional , Tanzanía
15.
Proc Natl Acad Sci U S A ; 115(40): 10130-10135, 2018 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-30224488

RESUMEN

Both exogenous and endogenous retroviruses have long been studied in mice, and some of the earliest mouse studies focused on the heritability of genetic factors influencing permissivity and resistance to infection. The prototypic retroviral restriction factor, Fv1, is now understood to exhibit a degree of control across multiple retroviral genera and is highly diverse within Mus To better understand the age and evolutionary history of Fv1, a comprehensive survey of the Muroidea was conducted, allowing the progenitor integration to be dated to ∼45 million years. Intact coding potential is visible beyond Mus, and sequence analysis reveals strong signatures of positive selection also within field mice, ApodemusFv1's survival for such a period implies a recurring and shifting retroviral burden imparting the necessary selective pressures-an influence likely also common to analogous factors. Regions of Fv1 adapt cooperatively, highlighting its preference for repeated structures and suggesting that this functionally constrained aspect of the retroviral capsid lattice presents a common target in the evolution of intrinsic immunity.


Asunto(s)
Evolución Molecular , Proteínas/genética , Animales , Ratones , Murinae
16.
Parasitol Res ; 117(10): 3347-3350, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30182257

RESUMEN

The riparian European mink (Mustela lutreola), currently surviving in only three unconnected sites in Europe, is now listed as a critically endangered species in the IUCN Red List of Threatened Species. Habitat loss and degradation, anthropogenic mortality, interaction with the feral American mink (Neovison vison), and infectious diseases are among the main causes of its decline. In the Spanish Foral Community of Navarra, where the highest density of M. lutreola in its western population has been detected, different studies and conservation measures are ongoing, including health studies on European mink, and invasive American mink control. We report here a case of severe parasitism with progressive physiological exhaustion in an aged free-ranging European mink female, which was accidentally captured and subsequently died in a live-trap targeting American mink. Checking of the small intestine revealed the presence of 17 entangled Versteria mustelae worms. To our knowledge, this is the first description of hyperinfestation by tapeworms in this species.


Asunto(s)
Infecciones por Cestodos/veterinaria , Visón/parasitología , Platelmintos/fisiología , Animales , Infecciones por Cestodos/epidemiología , Infecciones por Cestodos/parasitología , Especies en Peligro de Extinción/estadística & datos numéricos , Europa (Continente)/epidemiología , Femenino , Masculino , Platelmintos/genética , Platelmintos/aislamiento & purificación , España/epidemiología
18.
Sci Rep ; 6: 32046, 2016 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-27534370

RESUMEN

Paedomorphosis and metamorphosis are two major developmental processes that characterize the evolution of complex life cycles in many lineages. Whereas these processes were fixed in some taxa, they remained facultative in others, with alternative phenotypes expressed in the same populations. From a genetic perspective, it is still unknown whether such phenotypes form a single population or whether they show some patterns of isolation in syntopy. This has deep implications for understanding the evolution of the phenotypes, i.e. towards their persistence or their fixation and speciation. Newts and salamanders are excellent models to test this hypothesis because they exhibit both developmental processes in their populations: the aquatic paedomorphs retain gills, whereas the metamorphs are able to colonize land. Using microsatellite data of coexisting paedomorphic and metamorphic palmate newts (Lissotriton helveticus), we found that they formed a panmictic population, which evidences sexual compatibility between the two phenotypes. The high gene flow could be understood as an adaptation to unstable habitats in which phenotypic plasticity is favored over the fixation of developmental alternatives. This makes then possible the persistence of a polyphenism: only metamorphosis could be maintained in case of occasional drying whereas paedomorphosis could offer specific advantages in organisms remaining in water.


Asunto(s)
Evolución Biológica , Flujo Génico/fisiología , Salamandridae/genética , Urodelos/genética , Animales , Teorema de Bayes , ADN/análisis , ADN/metabolismo , Ecosistema , Variación Genética , Genotipo , Metamorfosis Biológica , Repeticiones de Microsatélite/genética , Fenotipo , Reacción en Cadena de la Polimerasa
19.
J Virol ; 90(18): 8169-80, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27384662

RESUMEN

UNLABELLED: Gibbon ape leukemia virus (GALV) and koala retrovirus (KoRV) most likely originated from a cross-species transmission of an ancestral retrovirus into koalas and gibbons via one or more intermediate as-yet-unknown hosts. A virus highly similar to GALV has been identified in an Australian native rodent (Melomys burtoni) after extensive screening of Australian wildlife. GALV-like viruses have also been discovered in several Southeast Asian species, although screening has not been extensive and viruses discovered to date are only distantly related to GALV. We therefore screened 26 Southeast Asian rodent species for KoRV- and GALV-like sequences, using hybridization capture and high-throughput sequencing, in the attempt to identify potential GALV and KoRV hosts. Only the individuals belonging to a newly discovered subspecies of Melomys burtoni from Indonesia were positive, yielding an endogenous provirus very closely related to a strain of GALV. The sequence of the critical receptor domain for GALV infection in the Indonesian M. burtoni subsp. was consistent with the susceptibility of the species to GALV infection. The second record of a GALV in M. burtoni provides further evidence that M. burtoni, and potentially other lineages within the widespread subfamily Murinae, may play a role in the spread of GALV-like viruses. The discovery of a GALV in the most western part of the Australo-Papuan distribution of M. burtoni, specifically in a transitional zone between Asia and Australia (Wallacea), may be relevant to the cross-species transmission to gibbons in Southeast Asia and broadens the known distribution of GALVs in wild rodents. IMPORTANCE: Gibbon ape leukemia virus (GALV) and the koala retrovirus (KoRV) are very closely related, yet their hosts neither are closely related nor overlap geographically. Direct cross-species infection between koalas and gibbons is unlikely. Therefore, GALV and KoRV may have arisen via a cross-species transfer from an intermediate host whose range overlaps those of both gibbons and koalas. Using hybridization capture and high-throughput sequencing, we have screened a wide range of rodent candidate hosts from Southeast Asia for KoRV- and GALV-like sequences. Only a Melomys burtoni subspecies from Wallacea (Indonesia) was positive for GALV. We report the genome sequence of this newly identified GALV, the critical domain for infection of its potential cellular receptor, and its phylogenetic relationships with the other previously characterized GALVs. We hypothesize that Melomys burtoni, and potentially related lineages with an Australo-Papuan distribution, may have played a key role in cross-species transmission to other taxa.


Asunto(s)
Virus de la Leucemia del Gibón/aislamiento & purificación , Murinae/virología , Infecciones por Retroviridae/veterinaria , Enfermedades de los Roedores/virología , Animales , Secuenciación de Nucleótidos de Alto Rendimiento , Indonesia , Virus de la Leucemia del Gibón/genética , Hibridación de Ácido Nucleico , Provirus/genética , Provirus/aislamiento & purificación , Infecciones por Retroviridae/virología , Análisis de Secuencia de ADN
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...