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1.
PLoS One ; 19(5): e0298591, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38758948

RESUMO

Amphibians globally suffer from emerging infectious diseases like chytridiomycosis caused by the continuously spreading chytrid fungi. One is Batrachochytrium salamandrivorans (Bsal) and its disease ‒ the 'salamander plague' ‒ which is lethal to several caudate taxa. Recently introduced into Western Europe, long distance dispersal of Bsal, likely through human mediation, has been reported. Herein we study if Alpine salamanders (Salamandra atra and S. lanzai) are yet affected by the salamander plague in the wild. Members of the genus Salamandra are highly susceptible to Bsal leading to the lethal disease. Moreover, ecological modelling has shown that the Alps and Dinarides, where Alpine salamanders occur, are generally suitable for Bsal. We analysed skin swabs of 818 individuals of Alpine salamanders and syntopic amphibians at 40 sites between 2017 to 2022. Further, we compiled those with published data from 319 individuals from 13 sites concluding that Bsal infections were not detected. Our results suggest that the salamander plague so far is absent from the geographic ranges of Alpine salamanders. That means that there is still a chance to timely implement surveillance strategies. Among others, we recommend prevention measures, citizen science approaches, and ex situ conservation breeding of endemic salamandrid lineages.


Assuntos
Batrachochytrium , Micoses , Urodelos , Animais , Batrachochytrium/genética , Batrachochytrium/patogenicidade , Micoses/veterinária , Micoses/microbiologia , Micoses/epidemiologia , Urodelos/microbiologia , Doenças Transmissíveis Emergentes/microbiologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/veterinária , Salamandra/microbiologia , Europa (Continente)/epidemiologia , Quitridiomicetos
2.
Anal Bioanal Chem ; 416(13): 3149-3160, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38563959

RESUMO

Bats are the second largest mammalian order and are an endangered species group with a strong need for contamination monitoring. To facilitate non-invasive monitoring of the ecological burden in bat populations, a multiresidue method for the simultaneous quantification of 119 analytes including pesticides, persistent organic pollutants (POPs), active pharmaceutical ingredients (APIs), polycyclic aromatic hydrocarbons (PAHs), UV blockers, plasticizers, and other emerging pollutants in bat guano with gas chromatography tandem mass spectrometry (GC-MS/MS) was developed. Sample preparation and clean-up were performed with a modified QuEChERS approach based on DIN EN 15662. The method uses 1.00 g bat guano as sample with acetonitrile and water for liquid-liquid extraction. Phase separation is assisted by citrate-buffered salting out agent. For clean-up of the extract, primary secondary amine (PSA) was combined with graphitized carbon black (GCB). The lower limits of quantification (LLOQ) ranged between 2.5 and 250 µg kg-1. Linearity was shown in a concentration range from the respective LLOQs to 1250 µg kg-1. The median of the mean recovery was 102.4%. Precision was tested at three concentrations. Method and injection precision were adequate with a relative standard deviation (RSD) below 20%. Furthermore, the comparative analysis with LC-MS/MS demonstrated the reliability of the results and provided a valuable extension of the analytical scope. As proof of concept, three guano samples from a German nursery roost of Myotis myotis were analysed. The results show a time-dependent change in contaminant concentration, highlighting the strong need for non-invasive contamination monitoring of whole bat populations.


Assuntos
Quirópteros , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Espectrometria de Massas em Tandem , Animais , Espectrometria de Massas em Tandem/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Reprodutibilidade dos Testes , Extração Líquido-Líquido/métodos , Monitoramento Ambiental/métodos
3.
Insects ; 15(4)2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38667379

RESUMO

Crop rotation is an important strategy for pest reduction. For mono-, or oligophagous pests that overwinter at a previously infested site, crop rotation means that the pests must find new host crop sites in the following year, and it is more efficient if a pest-specific distance is applied. Here, we report the development of a GIS-based tool for efficient cultivation planning using the example of the pest complex pea moth (Cydia nigricana) and grain and green peas (Pisum sativum). Monitoring data for four consecutive years (2016-2019) from 513 sites were used. Infestation of pea seeds and the distance to the previous year's pea sites were recorded. An adjustable Python script was developed by means of infestation-distance-correlation as a pest and crop-specific minimum migration distance (MD). The output of the tool is a risk map as decision support for cultivation planning. It shows different risk buffers with distances from 1261 m to 1825 m, depending on the cultivation type. The web tool is easily adjustable to other pests and crops anywhere in the world. The tool helps to prevent damages caused by agricultural, mono-, or oligophagous insect pests and consequently reduces pesticide applications for the benefit of the environment and biodiversity.

4.
PLoS One ; 19(4): e0298285, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38573887

RESUMO

For many species, population sizes are unknown despite their importance for conservation. For population size estimation, capture-mark-recapture (CMR) studies are often used, which include the necessity to identify each individual, mostly through individual markings or genetic characters. Invasive marking techniques, however, can negatively affect the individual fitness. Alternatives are low-impact techniques such as the use of photos for individual identification, for species with stable distinctive phenotypic traits. For the individual identification of photos, a variety of different software, with different requirements, is available. The European fire salamander (Salamandra salamandra) is a species in which individuals, both at the larval stage and as adults, have individual specific patterns that allow for individual identification. In this study, we compared the performance of five different software for the use of photographic identification for the European fire salamander: Amphibian & Reptile Wildbook (ARW), AmphIdent, I3S pattern+, ManderMatcher and Wild-ID. While adults can be identified by all five software, European fire salamander larvae can currently only be identified by two of the five (ARW and Wild-ID). We used one dataset of European fire salamander larval pictures taken in the laboratory and tested this dataset in two of the five software (ARW and Wild-ID). We used another dataset of European fire salamander adult pictures taken in the field and tested this using all five software. We compared the requirements of all software on the pictures used and calculated the False Rejection Rate (FRR) and the Recognition Rate (RR). For the larval dataset (421 pictures) we found that the ARW and Wild-ID performed equally well for individual identification (99.6% and 100% Recognition Rate, respectively). For the adult dataset (377 pictures), we found the best False Rejection Rate in ManderMatcher and the highest Recognition Rate in the ARW. Additionally, the ARW is the only program that requires no image pre-processing. In times of amphibian declines, non-invasive photo identification software allowing capture-mark-recapture studies help to gain knowledge on population sizes, distribution, movement and demography of a population and can thus help to support species conservation.


Assuntos
Salamandra , Humanos , Animais , Larva , Fenótipo , Fotografação , Software
5.
Sensors (Basel) ; 23(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37299963

RESUMO

We introduce a novel ultra-low power system for tracking animal movements over long periods with an unprecedented high-temporal-resolution. The localization principle is based on the detection of cellular base stations using a miniaturized software-defined radio, weighing 2.0 g, including the battery, and having a size equivalent to two stacked 1-euro cent coins. Therefore, the system is small and lightweight enough to be deployed on small, wide-ranging, or migrating animals, such as European bats, for movement analysis with an unprecedented spatiotemporal resolution. The position estimation relies on a post-processing probabilistic RF pattern-matching method based on the acquired base stations and power levels. In several field tests, the system has been successfully verified, and a run-time of close to one year has been demonstrated.


Assuntos
Animais Selvagens , Telemetria , Animais , Telemetria/métodos , Software , Fontes de Energia Elétrica
6.
Sci Rep ; 13(1): 6344, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072427

RESUMO

Hibernation is one of the most important behaviours of bats of the temperate zone. During winter, when little food or liquid water is available, hibernation in torpor lowers metabolic costs. However, the timing of emergence from hibernation is crucial for the resumption of the reproductive process in spring. Here, we investigate the spring emergence of six bat species or pairs of bat species of the genera Myotis and Plecotus at five hibernation sites in Central Europe over 5 years. Using generalized additive Poisson models (GAPMs), we analyze the influence of weather conditions (air and soil temperature, atmospheric pressure, atmospheric pressure trend, rain, wind, and cloud cover) as predictors of bat activity and separate these extrinsic triggers from residual motivation to emerge from hibernation (extrinsic factors not studied; intrinsic motivation). Although bats in a subterranean hibernaculum are more or less cut off from the outside world, all species showed weather dependence, albeit to varying degrees, with air temperature outside the hibernaculum having a significant positive effect in all species. The residual, potentially intrinsic motivation of species to emerge from their hibernacula corresponds to their general ecological adaptation, such as trophic specialization and roosting preferences. It allows the definition of three functional groups (high, medium and low residual activity groups) according to the degree of weather dependence of spring activity. A better knowledge of the interplay of extrinsic triggers and residual motivation (e.g., internal zeitgebers) for spring emergence will help to understand the flexibility of a species to adapt to a changing world.


Assuntos
Quirópteros , Hibernação , Torpor , Animais , Temperatura , Pressão Atmosférica
7.
Emerg Infect Dis ; 29(2): 411-414, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36692470

RESUMO

Skin fungi are among the most dangerous drivers of global amphibian declines, and few mitigation strategies are known. For Batrachochytrium salamandrivorans (Chytridiomycota), available treatments rely on temperature, partially combined with antifungal drugs. We report the clearance of B. salamandrivorans in 2 urodelan species using a solely drug-based approach.


Assuntos
Quitridiomicetos , Micoses , Animais , Micoses/veterinária , Micoses/microbiologia , Batrachochytrium , Anfíbios/microbiologia
8.
Mol Ecol Resour ; 23(2): 471-485, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36056614

RESUMO

Molecular gut content analysis is a popular tool to study food web interactions and has recently been suggested as an alternative source for DNA-based biomonitoring. However, the overabundant consumer's DNA often outcompetes that of its diet during PCR. Lineage-specific primers are an efficient means to reduce consumer amplification while retaining broad specificity for dietary taxa. Here, we designed an amplicon sequencing assay to monitor the eukaryotic diet of mussels and other metazoan filter feeders and explore the utility of mussels as natural eDNA samplers to monitor planktonic communities. We designed several lineage-specific rDNA primers with broad taxonomic suitability for eukaryotes. The primers were tested using DNA extracts of different limnic and marine mussel species and the results compared to eDNA water samples collected next to the mussel colonies. In addition, we analysed several 25-year time series samples of mussels from German rivers. Our primer sets efficiently prevent the amplification of mussels and other metazoans. The recovered DNA reflects a broad dietary preference across the eukaryotic tree of life and considerable taxonomic overlap with filtered water samples. We also show the utility of a reversed version of our primers, which prevents amplification of nonmetazoan taxa from complex eukaryote community samples, by enriching fauna associated with the marine brown algae Fucus vesiculosus. Our protocol will enable large-scale dietary analysis in metazoan filter feeders, facilitate aquatic food web analysis and allow surveying of aquacultures for pathogens. Moreover, we show that mussels and other aquatic filter feeders can serve as complementary DNA source for biomonitoring.


Assuntos
Bivalves , DNA Ambiental , Animais , DNA/genética , DNA/análise , Bivalves/genética , Dieta , Água/análise , Monitoramento Ambiental , Código de Barras de DNA Taxonômico/métodos
9.
Elife ; 112022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36354219

RESUMO

A major limitation of current reports on insect declines is the lack of standardized, long-term, and taxonomically broad time series. Here, we demonstrate the utility of environmental DNA from archived leaf material to characterize plant-associated arthropod communities. We base our work on several multi-decadal leaf time series from tree canopies in four land use types, which were sampled as part of a long-term environmental monitoring program across Germany. Using these highly standardized and well-preserved samples, we analyze temporal changes in communities of several thousand arthropod species belonging to 23 orders using metabarcoding and quantitative PCR. Our data do not support widespread declines of α-diversity or genetic variation within sites. Instead, we find a gradual community turnover, which results in temporal and spatial biotic homogenization, across all land use types and all arthropod orders. Our results suggest that insect decline is more complex than mere α-diversity loss, but can be driven by ß-diversity decay across space and time.


Insects are a barometer of environmental health. Ecosystems around the world are being subjected to unprecedented man-made stresses, ranging from climate change to pollution and intensive land use. These stresses have been associated with several recent, dramatic declines in insect populations, particularly in areas with heavily industrialised farming practices. Despite this, the links between insect decline, environmental stress, and ecosystem health are still poorly-understood. A decline in one area might look catastrophic, but could simply be part of normal, longer-term variations. Often, we do not know whether insect decline is a local phenomenon or reflects wider environmental trends. Additionally, most studies do not go far back enough in time or cover a wide enough geographical range to make these distinctions. To understand and combat insect decline, we therefore need reliable methods to monitor insect populations over long periods of time. To solve this problem, Krehenwinkel, Weber et al. gathered data on insect communities from a new source: tree leaves. Originally, these samples were collected to study air pollution, but they also happen to contain the DNA of insects that interacted with them before they were collected ­ for example, DNA deposited in chew marks where the insects had nibbled on the leaves. This is called environmental DNA, or eDNA for short. To survey the insect communities that lived in these trees, Krehenwinkel, Weber et al. first extracted eDNA from the leaves and sequenced it. Analysis of the different DNA sequences from the leaf samples revealed not only the number of insect species, but also the abundance (or rarity) of each species within each community. Importantly, the leaves had been collected and stored in stable conditions over several decades, allowing changes in these insect populations to be tracked over time. eDNA analysis revealed subtle changes in the make-up of forest insect communities. In the forests where the leaves were collected, the total number of insect species remained much the same over time. However, many individual species still declined, only to be replaced by newcomer species. These 'colonisers' are also widespread, which will likely lead to an overall pattern of fewer species that are more widely distributed ­ in other words, more homogeneity. The approach of Krehenwinkel, Weber et al. provides a reliable method to study insect populations in detail, over multiple decades, using archived samples from environmental studies. The information gained from this has real-world significance for environmental issues with enormous social impact, ranging from conservation, to agriculture and even public health.


Assuntos
Artrópodes , DNA Ambiental , Animais , Biodiversidade , Florestas , Insetos , Ecossistema
10.
Chemosphere ; 305: 135342, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35714958

RESUMO

Bats are strictly protected throughout Europe. They are a highly diverse order of mammals in terms of body size, body weight, migratory behaviour, trophic niche specialisation and habitat use. The latter ranges from urban areas and arable land to forest. Due to their low reproductive rate, environmental stressors can have a major impact on bat populations. Pesticides in particular are discussed as an important driver of bat population declines. In this work, we analysed nearly 400 animals of five different species (Eptesicus serotinus, Myotis myotis, Nyctalus noctula, Pipistrellus pipistrellus, and Plecotus auritus) from all over Germany for residues of 209 pesticides and persistent organic pollutants. Residue analysis was conducted with a previously developed method using a miniaturized quick, easy, cheap, effective, rugged and safe (QuEChERS) sample preparation and gas chromatography-tandem mass spectrometry for separation and detection. These analytical data were statistically correlated with the known data on the animals (e.g. age, sex, place and time of finding). Of 209 pesticides and pollutants investigated, 28 compounds were detected, the most frequent being organochlorine insecticides and polychlorinated biphenyls, which have been banned for decades by the Stockholm Convention on Persistent Organic Pollutants. Detection of more recent pesticides that were legally used for the last decade included azole antifungals and the insecticide fipronil. The bats contained between four and 25 different residues. Statistical data analyses showed that the distribution throughout Germany is largely comparable, and single exceptions were observed in specialized ecological niches. In conclusion, this work provides the largest dataset of pesticide and persistent organic pollutant residues in European bats to date.


Assuntos
Quirópteros , Inseticidas , Resíduos de Praguicidas , Praguicidas , Bifenilos Policlorados , Animais , Cromatografia Gasosa-Espectrometria de Massas/métodos , Inseticidas/análise , Poluentes Orgânicos Persistentes , Resíduos de Praguicidas/análise , Praguicidas/análise , Bifenilos Policlorados/análise
11.
J Pers Med ; 12(4)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35455651

RESUMO

BACKGROUND: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is associated with arrhythmic events which may lead to sudden cardiac death (SCD). A leading therapy for CPVT besides medical treatment with beta-blockers is the use of an implantable cardioverter-defibrillator (ICD). For this paper we compared data from a pooled analysis to get further evidence about the complications of transvenous and subcutaneous ICDs. METHODS: We gathered data from a search of PubMed, Web of Science, Cochrane Library and Cinahl. For our analysis, we chose 30 studies with a total number of 784 patients. We compared the data regarding complications caused by different ICD device types. RESULTS: During a mean follow up of 38.9 months for the patients with ICD implantation (n = 337), data showed a complication rate of 101 (30%). A total of 330 (98%) of them received a transvenous-ICD (T-ICD) and 7 (2%) a subcutaneous-ICD (S-ICD). A total of 97 (29.4%) of the T-ICD patients and 4 (57.1%) of the S-ICD patients had at least one complication. Of the 234 complications that occurred in T-ICD patients 152 (65%) were inappropriate shocks due to supraventricular arrhythmias, T/R-wave oversensing or electrode defect, 26 (11.1%) lead fracture/failure, 1 (0.4%) electrode defect, 46 were (19.7%) events of electrical storms, 1 (0.4%) thromboembolic event, 2 (0.8%) cases of endocarditis and 6 (2.6%) infections of the ICD-pocket. Ten (100%) of the complications for the four patients with the S-ICD were an event of an inappropriate shock due to supraventricular arrhythmias, T/R-wave oversensing or electrode defect. CONCLUSION: Subcutaneous ICDs (S-ICD) show a certain advantage over T-ICDs regarding lead-related complications. Nevertheless, they still show problems with inappropriate shocks and other ICD related complications. Therefore, a case-by-case decision is advised, but the continuous improvement of S-ICD might make it an overall advantageous therapy option in the future.

12.
Sci Rep ; 12(1): 3275, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35228557

RESUMO

The larval stage of the European fire salamander (Salamandra salamandra) inhabits both lentic and lotic habitats. In the latter, they are constantly exposed to unidirectional water flow, which has been shown to cause downstream drift in a variety of taxa. In this study, a closed artificial creek, which allowed us to keep the water flow constant over time and, at the same time, to simulates with predefined water quantities and durations, was used to examine the individual movement patterns of marked larval fire salamanders exposed to unidirectional flow. Movements were tracked by marking the larvae with VIAlpha tags individually and by using downstream and upstream traps. Most individuals showed stationarity, while downstream drift dominated the overall movement pattern. Upstream movements were rare and occurred only on small distances of about 30 cm; downstream drift distances exceeded 10 m (until next downstream trap). The simulated flood events increased drift rates significantly, even several days after the flood simulation experiments. Drift probability increased with decreasing body size and decreasing nutritional status. Our results support the production hypothesis as an explanation for the movements of European fire salamander larvae within creeks.


Assuntos
Salamandra , Animais , Tamanho Corporal , Ecossistema , Humanos , Larva , Água
13.
Animals (Basel) ; 11(6)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201034

RESUMO

We performed the first cytogenetic analysis on five out of the seven species of the genus Lyciasalamandra, including seven subspecies, and representatives of its sister genus Salamandra. All the studied species have a similar karyotype of 2n = 24, mostly composed of biarmed elements. C-bands were observed on all chromosomes, at centromeric, telomeric and interstitial position. We found a peculiar taxon-specific NOR configuration, including either heteromorphic and homomorphic NORs on distinct regions of different chromosomes. Lyciasalamandra a.antalyana and L. helverseni showed two homomorphic NORs (pairs 8 and 2, respectively), while heteromorphic NORs were found in L. billae (pairs 6, 12), L. flavimembris (pairs 2, 12), L. l. luschani (pairs 2, 12), L. l. basoglui (pairs 6, 12), L. l. finikensis (pairs 2, 6) and S. lanzai (pairs 8, 10). Homomorphic NORs with an additional supernumerary site were shown by S. s. salamandra (pairs 2, 8) and S. s. gigliolii (pairs 2, 10). This unexpected highly variable NOR configuration is probably derived from multiple independent NOR translocations and paracentric inversions and correlated to lineage divergence in Lyciasalamandra. These results support the taxonomic validity of the studied taxa and are consistent with a hypothesized scenario of synchronous evolution in the genus.

14.
BMC Zool ; 6(1): 28, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37170302

RESUMO

BACKGROUND: The morphology of anuran larvae is suggested to differ between species with tadpoles living in standing (lentic) and running (lotic) waters. To explore which character combinations within the general tadpole morphospace are associated with these habitats, we studied categorical and metric larval data of 123 (one third of which from lotic environments) Madagascan anurans. RESULTS: Using univariate and multivariate statistics, we found that certain combinations of fin height, body musculature and eye size prevail either in larvae from lentic or lotic environments. CONCLUSION: Evidence for adaptation to lotic conditions in larvae of Madagascan anurans is presented. While lentic tadpoles typically show narrow to moderate oral discs, small to medium sized eyes, convex or moderately low fins and non-robust tail muscles, tadpoles from lotic environments typically show moderate to broad oral discs, medium to big sized eyes, low fins and a robust tail muscle.

15.
Mol Phylogenet Evol ; 155: 106967, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33031928

RESUMO

Hybridization can leave genealogical signatures in an organism's genome, originating from the parental lineages and persisting over time. This potentially confounds phylogenetic inference methods that aim to represent evolution as a strictly bifurcating tree. We apply a phylotranscriptomic approach to study the evolutionary history of, and test for inter-lineage introgression in the Salamandridae, a Holarctic salamanders group of interest in studies of toxicity and aposematism, courtship behavior, and molecular evolution. Although the relationships between the 21 currently recognized salamandrid genera have been the subject of numerous molecular phylogenetic studies, some branches have remained controversial and sometimes affected by discordances between mitochondrial vs. nuclear trees. To resolve the phylogeny of this family, and understand the source of mito-nuclear discordance, we generated new transcriptomic (RNAseq) data for 20 salamandrids and used these along with published data, including 28 mitochondrial genomes, to obtain a comprehensive nuclear and mitochondrial perspective on salamandrid evolution. Our final phylotranscriptomic data set included 5455 gene alignments for 40 species representing 17 of the 21 salamandrid genera. Using concatenation and species-tree phylogenetic methods, we find (1) Salamandrina sister to the clade of the "True Salamanders" (consisting of Chioglossa, Mertensiella, Lyciasalamandra, and Salamandra), (2) Ichthyosaura sister to the Near Eastern genera Neurergus and Ommatotriton, (3) Triturus sister to Lissotriton, and (4) Cynops paraphyletic with respect to Paramesotriton and Pachytriton. Combining introgression tests and phylogenetic networks, we find evidence for introgression among taxa within the clades of "Modern Asian Newts" and "Modern European Newts". However, we could not unambiguously identify the number, position, and direction of introgressive events. Combining evidence from nuclear gene analysis with the observed mito-nuclear phylogenetic discordances, we hypothesize a scenario with hybridization and mitochondrial capture among ancestral lineages of (1) Lissotriton into Ichthyosaura and (2) Triturus into Calotriton, plus introgression of nuclear genes from Triturus into Lissotriton. Furthermore, both mitochondrial capture and nuclear introgression may have occurred among lineages assigned to Cynops. More comprehensive genomic data will, in the future, allow testing this against alternative scenarios involving hybridization with other, extinct lineages of newts.


Assuntos
Hibridização Genética , Filogenia , Urodelos/classificação , Urodelos/genética , Animais , Núcleo Celular/genética , DNA Mitocondrial/genética , Genoma Mitocondrial , Mitocôndrias/genética , Transcriptoma/genética
16.
J Fungi (Basel) ; 6(4)2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33022972

RESUMO

Infectious diseases are major drivers of biodiversity loss. The risk of fungal diseases to the survival of threatened animals in nature is determined by a complex interplay between host, pathogen and environment. We here predict the risk of invasion of populations of threatened Mediterranean salamanders of the genus Lyciasalamandra by the pathogenic chytrid fungus Batrachochytrium salamandrivorans by combining field sampling and lab trials. In 494 samples across all seven species of Lyciasalamandra, B. salamandrivorans was found to be absent. Single exposure to a low (1000) number of fungal zoospores resulted in fast buildup of lethal infections in three L. helverseni. Thermal preference of the salamanders was well within the thermal envelope of the pathogen and body temperatures never exceeded the fungus' thermal critical maximum, limiting the salamanders' defense opportunities. The relatively low thermal host preference largely invalidates macroclimatic based habitat suitability predictions and, combined with current pathogen absence and high host densities, suggests a high probability of local salamander population declines upon invasion by B. salamandrivorans. However, the unfavorable landscape that shaped intraspecific host genetic diversity, lack of known alternative hosts and rapid host mortality after infection present barriers to further, natural pathogen dispersal between populations and thus species extinction. The risk of anthropogenic spread stresses the importance of biosecurity in amphibian habitats.

17.
Ecology ; 101(8): e03088, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32320485

RESUMO

Individual diet specialization (IS) has important community- and population-level implications and its ecological drivers are actively investigated. Here, to test the hypothesis that local environmental conditions may influence IS in wild populations, we analyzed the stomach contents of 395 individuals from eight populations of five allopatric species of European cave salamanders (genus Hydromantes). We assessed whether their degree of individual diet specialization (1) scaled positively with the respective niche widths, in agreement with Van Valen's niche variation hypothesis (NVH), and (2) could be predicted by satellite-derived climatic and vegetation characteristics of the sites where the populations live. Consistent with the NVH, the degree of individual diet specialization increased with the populations' total niche width. Furthermore, two variables describing local nonarboreal vegetation cover and habitat heterogeneity successfully predicted the variation in individual specialization across the eight populations. Climatic factors had a generally low predictive power, with individual specialization in low- and high-elevation populations showing contrasting patterns of co-variation with air temperature in the warmest quarter of the year. However, independently from elevation, specialization peaked under conditions of high nonarboreal vegetation cover and high precipitation regimes. We discussed the results against two mutually nonexclusive scenarios hypothesizing different mechanisms linking environmental factors to salamanders' trophic strategy at an individual and population level. We concluded that satellite-derived climatic and vegetation variables to date generally adopted to model Grinnellian niches might also be useful in predicting spatial variations in dietary habits of populations, that is, their Eltonian niches.


Assuntos
Dieta , Ecossistema , Comportamento Alimentar , Humanos
18.
J Clin Med ; 9(4)2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-32218223

RESUMO

Background: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare inherited disorder causing life-threatening arrhythmias. Long-term outcome studies of the channelopathy are limited. Objective: The aim of the present study was to summarize our knowledge on CPVT patients, including the clinical profile treatment approach and long-term outcome. Methods: In this single center study, we retrospectively and prospectively collected data from nine CPVT patients and analyzed them. Results: We reviewed nine patients with CPVT in seven families (22% male), with a median follow-up time of 8.6 years. Mean age at diagnosis was 26.4 12 years. Symptoms at admission were syncope (four patients) and aborted cardiac arrest (four patients). Family history of sudden cardiac death was screened in five patients. In genetic analyses, we found five patients with ryanodine type 2 receptor (RYR2) mutations. Seven patients were treated with beta-blockers, and if symptoms persisted flecainide was added (four patients). Despite beta-blocker treatment, three patients suffered from seven adverse cardiac events. An implantable cardioverter defibrillator was implanted in seven patients (one primary, six secondary prevention). Over the follow-up period, three patients suffered from ventricular tachycardia (ten times) and five patients from ventricular fibrillation (nine times). No one died during follow-up. Conclusion: Our CPVT cohort showed a high risk of cardiac events. Family screening, optimal medical therapy and individualized treatment are necessary in affected patients in referral centers.

19.
Biodivers Data J ; 8: e48623, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32076380

RESUMO

BACKGROUND: Systematic data collection on species and their exploited environments is of key importance for conservation studies. Within the less-known environments, the subterranean ones are neither easy to be studied, nor to be explored. Subterranean environments house a wide number of specialised organisms, many of which show high sensitivity to habitat alteration. Despite the undeniable importance to monitor the status of the subterranean biodiversity, standardised methodologies to record biotic and abiotic data in these environments are still not fully adopted, impeding therefore the creation of comparable datasets useful for monitoring the ecological condition in the subterranean environments and for conservation assessment of related species. NEW INFORMATION: In this work we describe a methodology allowing the collection of standardised abiotic and biotic data in subterranean environments. To show this, we created a large dataset including information on environmental features (morphology and microclimate) and abundance of five predators (one salamander, three spiders and one snail) occurring in seven caves of the Monte Albo (Sardinia, Italy), an important biodiversity hotspot. We performed 77 surveys on 5,748 m2 of subterranean environments througout a year, recording 1,695 observations of the five cave predators. The fine-scale data collection adopted in our methodology allowed us to record detailed information related to both morphology and microclimate of the cave inner environment. Furthermore, this method allows us to account for species-imperfect detection when recording presence/abundance data.

20.
PLoS One ; 15(1): e0226326, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929551

RESUMO

Lycian salamanders (genus Lyciasalamandra) constitute an exceptional case of micro-endemism of an amphibian species on the Asian Minor mainland. These viviparous salamanders are confined to karstic limestone formations along the southern Anatolian coast and some islands. We here study the genetic differentiation within and among 118 populations of all seven Lyciasalamandra species across the entire genus' distribution. Based on circa 900 base pairs of fragments of the mitochondrial 16SrDNA and ATPase genes, we analysed the spatial haplotype distribution as well as the genetic structure and demographic history of populations. We used 253 geo-referenced populations and CHELSA climate data to infer species distribution models which we projected on climatic conditions of the Last Glacial Maximum (LGM). Within all but one species, distinct phyloclades were identified, which only in parts matched current taxonomy. Most haplotypes (78%) were private to single populations. Sometimes population genetic parameters showed contradicting results, although in several cases they indicated recent population expansion of phyloclades. Climatic suitability of localities currently inhabited by salamanders was significantly lower during the LGM compared to recent climate. All data indicated a strong degree of isolation among Lyciasalamandra populations, even within phyloclades. Given the sometimes high degree of haplotype differentiation between adjacent populations, they must have survived periods of deteriorated climates during the Quaternary on the spot. However, the alternative explanation of male biased dispersal combined with a pronounced female philopatry can only be excluded if independent nuclear data confirm this result.


Assuntos
Variação Genética , Salamandridae/genética , Adenosina Trifosfatases/química , Adenosina Trifosfatases/classificação , Adenosina Trifosfatases/genética , Animais , Clima , DNA Mitocondrial/genética , Haplótipos , Filogenia , Filogeografia , Dinâmica Populacional , RNA Ribossômico 16S/química , RNA Ribossômico 16S/classificação , RNA Ribossômico 16S/genética , Salamandridae/classificação
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