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1.
Immunogenetics ; 76(1): 37-50, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38114658

RESUMEN

In natural populations, hybridization is known to occur between a wide range of species. However, its evolutionary significance is less clear. Genes involved in fighting pathogens are considered excellent candidates for studying adaptive introgression, although both introgression and balancing selection can generate similar patterns of diversity and differentiation. Here, we compared DQA and DQB MHC class II and microsatellite allelic diversity of sympatric and parapatric mountain (Lepus timidus) and brown hare (L. europaeus) populations from Switzerland. We detected higher genetic diversity in brown hares compared to mountain hares at both MHC and microsatellite loci. We consider the observed patterns of microsatellite diversity both for L. europaeus and L. timidus as result of stochastic demographic processes while the pattern of MHC polymorphism of the studied hare populations can be explained by pathogen-driven selection. Rare bidirectional gene flow between both hare species seems to occur specifically for MHC alleles. However, the high number of shared alleles showing similar high frequency in both species suggests that reciprocally exchanged MHC alleles are being maintained via balancing selection. Adaptation to similar pathogen communities can also lead to parallel selection of MHC alleles. Positive selection, recombination and mutations have played different roles in shaping the patterns of MHC allelic diversity in and differentiation between both species. Results for the latter evolutionary forces do not show a better matching between the sympatric populations compared to the parapatric ones, suggesting a minor role of introgression for the observed evolutionary patterns of the studied hare species.


Asunto(s)
Liebres , Animales , Liebres/genética , Suiza , Filogenia , Polimorfismo Genético , Exones
2.
Int J Mol Sci ; 24(16)2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37629107

RESUMEN

Linguatula serrata (Frölich, 1789) is a widespread parasite known as the tongue worm belonging to the family Linguatulidae. The adult form of the parasite is usually located in the upper respiratory tract of domestic and wild carnivores while the larval forms are located in the visceral organs of intermediate hosts (various herbivorous mammals). Twenty-four European brown hares (Lepus europaeus) were examined in this study, of which two were positive with L. serrata nymphs. The collected nymphs were examined morphologically using electron-microscopic analysis and molecularly by amplification of 18S rRNA and COX1 genes. Lung tissue samples were also collected and histopathological examination was performed. Histopathological examination revealed the following lesions: generalized inflammatory oedema, granulomas with necrosis, calcification and fibrosis in the bronchial tree. The results of molecular sequencing for L. serrata specimens collected from the European brown hares are deposited in GenBank. This study presents the first report on Linguatula serrata nymphs collected from L. europaeus in Romania, using molecular and morphological characterization simultaneously.


Asunto(s)
Gastrópodos , Liebres , Lagomorpha , Pentastomida , Animales , Liebres/genética , Pentastomida/genética , Rumanía , Calcificación Fisiológica , Ninfa
3.
Fish Shellfish Immunol ; 122: 409-418, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35183739

RESUMEN

The members in the family Aplysidae known as sea hares play a crucial role as a grazer in small tidal pools or shallow subtidal hard bottoms. Like other marine gastropods, hemocyte types and functions of sea hares are limitedly known. This study identified and characterized the hemocytes of common Aplysia species Aplysia kurodai, A. juliana, and A. oculifera in rocky tidal pools in Jeju Island off the south coast of Korea using flow cytometry and light microscopy. The flow cytometry identified three different hemocytes in the hemolymph of the three sea hare species: granulocytes, hyalinocytes, and blast-like cells. The granulocytes exhibited pseudopodia on the cell surface and granules in the cytoplasm. Morphology of the hyalinocyte was similar to that of the granulocytes, while they lack cytoplasmic granules. The blast-like cells were small and round, with very thin cytoplasm. The hyalinocytes were the most abundant in the hemolymph, accounting for 89.8-92.6% of the total hemocytes. Flow cytometry indicated that the granulocytes and blast-like cells were less than 5.6% and 5.4% of the total hemocyte populations. Flow cytometry also revealed that the granulocytes and hyalinocytes are engaged in cellular defensive activities such as intra-cellular lysosomal content, phagocytosis, and ROS production. The mean lysosomal contents of the granulocytes (0.4 × 105-0.2 × 105 A U.) were 2-3 times higher than that of hyalinocytes (0.2 × 105-0.6 × 105 A U.). In addition, the ROS production of the granulocytes (0.98 × 106-1.95 × 106 A U.) was about twice higher than that of the hyalinocytes (0.62 × 106-1.14 × 106 A U.). Of the three species of sea hares, the granulocytes showed comparatively higher phagocytosis capacity (70.4-92.3%) than that of the hyalinocytes (34.8-46.0%). Flow cytometry and microscopy indicated that the hemocyte types and their functions were identical, regardless of the species.


Asunto(s)
Gastrópodos/clasificación , Hemocitos , Animales , Aplysia , Citometría de Flujo , Gastrópodos/citología , Islas , Fagocitosis , Especies Reactivas de Oxígeno/metabolismo , República de Corea
4.
Vet Pathol ; 59(2): 353-357, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35001758

RESUMEN

Spontaneous migration of placental trophoblasts into maternal blood vessels and embolization to other organs (ie, lung, adrenal gland, spleen, and liver) occurs in women and certain animals with hemochorial placentation. Although considered incidental in most species, increased incidence and numbers of trophoblast emboli are reported in women with gestational diseases with arterial hypertension (pre-eclampsia and eclampsia). To the best of our knowledge, trophoblast emboli have not been reported in lagomorphs. This case report describes the identification of trophoblast emboli in the lung of a wild snowshoe hare (Lepus americanus). Death of this hare was attributed to pulmonary hemorrhages and hemothorax, but a definitive cause for the hemorrhages was not determined. It is unclear whether trophoblast embolism normally occurs in this species and represents an incidental finding, or whether it possibly contributed to rupture of pulmonary or thoracic blood vessels leading to hemorrhage.


Asunto(s)
Embolia , Liebres , Animales , Embolia/veterinaria , Femenino , Humanos , Pulmón , Placenta , Embarazo , Trofoblastos
5.
J Anim Ecol ; 90(4): 875-885, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33368272

RESUMEN

Anthropogenic noise is a complex disturbance known to elicit a variety of responses in wild animals. Most studies examining the effects of noise on wildlife focus on vocal species, although theory suggests that the acoustic environment influences non-vocal species as well. Common mammalian prey species, like mule deer and hares and rabbits (members of the family Leporidae), rely on acoustic cues for information regarding predation, but the impacts of noise on their behaviour has received little attention. We paired acoustic recorders with camera traps to explore how average daily levels of anthropogenic noise from natural gas activity impacted occupancy and detection of mammalian herbivores in an energy field in the production phase of development. We consider the effects of noise in the context of several physical landscape variables associated with natural gas infrastructure that are known to influence habitat use patterns in mule deer. Our results suggest that mule deer detection probability was influenced by the interaction between physical landscape features and anthropogenic noise, with noise strongly reducing habitat use. In contrast, leporid habitat use was not related to noise but was influenced by landscape features. Notably, mule deer showed a stronger predicted negative response to roads with high noise exposure. This study highlights the complex interactions of anthropogenic disturbance and wildlife distribution and presents important evidence that the effects of anthropogenic noise should be considered in research focused on non-vocal specialist species and management plans for mule deer and other large ungulates.


El ruido de origen antropogénico es una perturbación compleja que provoca una variedad de respuestas en la fauna silvestre. La mayoría de los estudios que examina los efectos del ruido en fauna silvestre se enfoca en especies que se comunican con vocalizaciones, sin embargo, la teoría sugiere que el ambiente acústico es también un recurso clave para especies no-vocales. Especies de mamíferos comunes como el venado bura, liebres y conejos (miembros de la familia Leporidae), dependen de señales acústicas para detectar depredadores, pero los impactos del ruido en el comportamiento de estas especies han recibido poca atención de los investigadores. Usando grabadoras y cámaras trampa en conjunto, exploramos como los niveles diarios de ruido antropogénico generados por la extracción de gas natural impactaron la ocupación y detección de mamíferos herbívoros en un campo de extracción de energía en la fase de producción de desarrollo. Consideramos los efectos del ruido en el contexto de varias variables físicas del paisaje asociadas con la infraestructura del gas natural, que sabemos, influencian los patrones de uso de hábitat del venado bura. Nuestros resultados sugieren que la probabilidad de detección del venado bura fue influenciada por la interacción de las características físicas del paisaje y el ruido antropogénico, este último reduciendo de manera importante el uso de hábitat. En contraste, el uso de hábitat de lepóridos no se relacionó con ruido, pero fue influenciado por variables del paisaje. Notablemente, el venado bura mostro una predicción de respuesta fuerte a los caminos con niveles altos de ruido. Este estudio señala las complejas interacciones entre perturbaciones antropogénicas y la distribución de fauna silvestre. También presentamos evidencia importante que señala que los efectos del ruido antropogénico deben ser considerados en investigaciones enfocadas en especies especialistas no-vocales y planes de manejo para el venado bura y otros ungulados grandes.


Asunto(s)
Ciervos , Herbivoria , Animales , Ecosistema , Gas Natural , Conducta Predatoria , Conejos
6.
Parasitology ; 148(6): 740-746, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33536088

RESUMEN

Parasite surveys were conducted for 1­2 years in the Kruger National Park (KNP), South Africa on blue wildebeest, impalas, greater kudus, common warthogs and scrub hares. The host associations of some of the gastrointestinal nematode species infecting ≥60% of at least one of the five host species, were determined. These were Agriostomum gorgonis, Cooperia acutispiculum, Cooperia connochaeti, Cooperia hungi, Cooperia neitzi, Cooperioides hamiltoni, Gaigeria pachyscelis, Haemonchus bedfordi, Haemonchus krugeri, Haemonchus vegliai, Impalaia tuberculata, Longistrongylus sabie, Strongyloides papillosus, Trichostrongylus deflexus and Trichostrongylus thomasi. Although the prevalence of Trichostrongylus falculatus did not exceed 50% in any host species, it was present in all five hosts. Nematodes in the KNP range from those exhibiting strict host associations to generalists. Nematode-host associations may be determined by host feeding patterns and habitat use. Eight ixodid tick species were commonly collected from the same animals and in 2­3 year long surveys from plains zebras and helmeted guinea fowls: Amblyomma hebraeum, Amblyomma marmoreum, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus decoloratus, Rhipicephalus evertsi evertsi, Rhipicephalus simus and Rhipicephalus zambeziensis. Host specificity was less pronounced in ixodid tick species than in nematodes and the immature stages of five tick species infested all host species examined.


Asunto(s)
Animales Salvajes/parasitología , Ixodidae/clasificación , Infecciones por Nematodos/veterinaria , Infestaciones por Garrapatas/veterinaria , Animales , Antílopes/clasificación , Antílopes/parasitología , Equidae/parasitología , Galliformes/parasitología , Liebres/parasitología , Interacciones Huésped-Parásitos , Infecciones por Nematodos/epidemiología , Infecciones por Nematodos/parasitología , Sudáfrica/epidemiología , Porcinos/parasitología , Infestaciones por Garrapatas/epidemiología , Infestaciones por Garrapatas/parasitología
7.
Emerg Infect Dis ; 26(12): 2899-2906, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33219653

RESUMEN

Tick-borne encephalitis (TBE) is an endemic infection of public health importance in Finland. We investigated the effect of ecologic factors on 2007-2017 TBE trends. We obtained domestic TBE case data from the National Infectious Diseases Register, weather data from the US National Oceanic and Atmospheric Administration, and data from the Natural Resources Institute in Finland on mammals killed by hunters yearly in game management areas. We performed a mixed-effects time-series analysis with time lags on weather and animal parameters, adding a random effect to game management areas. During 2007-2017, a total of 395/460 (86%) domestic TBE cases were reported with known place of exposure and date of sampling. Overall, TBE incidence increased yearly by 15%. After adjusting for the density of other animals and minimum temperatures, we found thatTBE incidence was positively associated with white-tailed deer density. Variation in host animal density should be considered when assessing TBE risks and designing interventions.


Asunto(s)
Ciervos , Virus de la Encefalitis Transmitidos por Garrapatas , Encefalitis Transmitida por Garrapatas , Ixodes , Animales , Encefalitis Transmitida por Garrapatas/epidemiología , Finlandia/epidemiología , Densidad de Población
8.
Glob Chang Biol ; 26(7): 3809-3820, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32243648

RESUMEN

Habitat connectivity is a key factor influencing species range dynamics. Rapid warming in the Arctic is leading to widespread heterogeneous shrub expansion, but impacts of these habitat changes on range dynamics for large herbivores are not well understood. We use the climate-shrub-moose system of northern Alaska as a case study to examine how shrub habitat will respond to predicted future warming, and how these changes may impact habitat connectivity and the distribution of moose (Alces alces). We used a 19 year moose location dataset, a 568 km transect of field shrub sampling, and forecasted warming scenarios with regional downscaling to map current and projected shrub habitat for moose on the North Slope of Alaska. The tall-shrub habitat for moose exhibited a dendritic spatial configuration correlated with river corridor networks and mean July temperature. Warming scenarios predict that moose habitat will more than double by 2099. Forecasted warming is predicted to increase the spatial cohesion of the habitat network that diminishes effects of fragmentation, which improves overall habitat quality and likely expands the range of moose. These findings demonstrate how climate change may increase habitat connectivity and alter the distributions of shrub herbivores in the Arctic, including creation of novel communities and ecosystems.


Asunto(s)
Ecosistema , Herbivoria , Alaska , Animales , Regiones Árticas , Cambio Climático
9.
Mol Biol Rep ; 47(4): 2975-2984, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32236892

RESUMEN

Toll-like receptors (TLRs) are transmembrane proteins of the innate immune system, composed of the ectodomain involved in pathogen recognition and the intracellular Toll/interleukin-1 receptor (TIR) domain important for downstream signal transduction. Here, we analyze the genetic variability of TIR nucleotide and amino-acid sequences of the TLR2 gene in 243 brown hares from Europe and the Middle East and tested for the presence of selection signals and spatial structuring. TLR2 TIR domain sequences were PCR amplified and sequenced, while genotyping was performed by phasing. Genetic diversity indices were calculated in DnaSP and Arlequin, while presence of selection signals was tested using MEGA and the Datamonkey web server. The presence of spatial patterns in TIR sequence distribution was tested by spatial Principal Component Analysis (sPCA) in adegenet. A total of 13 haplotypes were revealed with haplotype diversity of 0.424, and nucleotide diversity (π) of 0.00138. Two spatial clusters were revealed: "Anatolia/Middle East" and "Europe". In Anatolia the two most prevalent amino-acid variants, A and B (the latter being the most ancestral) were maintained at similar frequencies; but in Europe a shift in genotype frequencies was observed as well as a higher number of nonsynonymous substitutions giving rise to novel amino-acid protein variants originating from the evolutionarily younger protein variant. Molecular diversity (haplotype and nucleotide diversity) indices were significantly higher in the "Anatolia/Middle East" cluster. A signal of purifying selection was detected acting on the TIR sequences.


Asunto(s)
Liebres/genética , Receptor Toll-Like 2/genética , Alelos , Animales , Evolución Biológica , Europa (Continente) , Evolución Molecular , Variación Genética/genética , Genotipo , Haplotipos/genética , Liebres/metabolismo , Medio Oriente , Filogenia , Selección Genética/genética , Análisis de Secuencia de ADN/métodos , Receptor Toll-Like 2/metabolismo , Receptores Toll-Like/genética
10.
Emerg Infect Dis ; 25(6): 1233-1235, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31107217

RESUMEN

Rabbit-associated hepatitis E viruses (HEVs) cause zoonotic infections. We investigated 2,389 hares in Germany during 2007-2014. Complete genome characterization of a hare-associated HEV strain revealed close genomic relatedness to rabbit-associated HEV strains. Although hare-specific HEV seroprevalence was low, at 2.6%, hares represent a potential source of sporadic HEV infections.


Asunto(s)
Liebres/virología , Hepatitis E/veterinaria , Zoonosis/epidemiología , Zoonosis/virología , Animales , Animales Salvajes , Genes Virales , Alemania/epidemiología , Virus de la Hepatitis E/genética , Historia del Siglo XXI , Filogenia , Vigilancia en Salud Pública , Estudios Seroepidemiológicos , Zoonosis/historia , Zoonosis/transmisión
11.
Proc Biol Sci ; 285(1875)2018 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-29563267

RESUMEN

Population cycles are one of nature's great mysteries. For almost a hundred years, innumerable studies have probed the causes of cyclic dynamics in snowshoe hares, voles and lemmings, forest Lepidoptera and grouse. Even though cyclic species have very different life histories, similarities in mechanisms related to their dynamics are apparent. In addition to high reproductive rates and density-related mortality from predators, pathogens or parasitoids, other characteristics include transgenerational reduced reproduction and dispersal with increasing-peak densities, and genetic similarity among populations. Experiments to stop cyclic dynamics and comparisons of cyclic and noncyclic populations provide some understanding but both reproduction and mortality must be considered. What determines variation in amplitude and periodicity of population outbreaks remains a mystery.


Asunto(s)
Arvicolinae , Galliformes , Liebres , Lepidópteros , Animales , Epigénesis Genética , Fertilidad , Mortalidad , Población , Densidad de Población , Dinámica Poblacional , Reproducción
12.
Foodborne Pathog Dis ; 15(9): 544-547, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29782189

RESUMEN

Currently, there is no information available on the detection of Toxoplasma gondii and Neospora caninum in the tissues of Tolai hares in China. This study aimed to investigate the prevalence of these protozoan parasites in Tolai hares obtained from Shandong province, eastern China, between January 2016 and June 2017. Serum and brain tissue samples of 358 Tolai hares were obtained and detected for the presence of antibody and parasite DNAs by serodiagnosis and polymerase chain reaction (PCR), respectively. The seroprevalence of T. gondii and N. caninum infection in Tolai hares was 8.10% (29/358) and 0.84% (3/358), respectively. However, all the 358 tested Tolai hares were negative for N. caninum by PCR and T. gondii DNA was detected in 23 Tolai hares (6.42%, 23/358). The positive T. gondii DNA was genotyped at 11 genetic markers using multilocus PCR-restriction fragment length polymorphism technology. Of the 23 positive samples, only 2 of them produced complete genotyping results, and were identified as ToxoDB Genotype #9. This is the first report to detect T. gondii in the tissues of Tolai hares from China and the first study to focus on N. caninum in Tolai hares from China.


Asunto(s)
Liebres/parasitología , Neospora/genética , Toxoplasma/genética , Toxoplasmosis Animal/epidemiología , Animales , Anticuerpos Antiprotozoarios/sangre , China/epidemiología , Coccidiosis/parasitología , ADN Protozoario/análisis , Femenino , Inocuidad de los Alimentos , Genotipo , Liebres/sangre , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción
13.
BMC Evol Biol ; 17(1): 46, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-28173765

RESUMEN

BACKGROUND: Recent studies of selection on mitochondrial (mt) OXPHOS genes suggest adaptation due mainly to environmental variation. In this context, Tunisian hares that display several external phenotypes with phylogenetically rather homogenous gene pool and shallow population structure provide a good precondition to detect positive selection on mt genes related to environmental/climatic variation, specifically ambient temperature and precipitation. RESULTS: We used codon-based methods along with population genetic data to test for positive selection on ATPase synthase 6 (ATP6) and NADH dehydrogenase 2 (ND2) of cape hares (Lepus capensis) collected along a steep ecological gradient in Tunisia. We found significantly higher differentiation at the ATP6 locus across Tunisia, with sub-humid Mediterranean, semi-arid, and arid Sahara climate than for fourteen unlinked supposedly neutrally evolving nuclear microsatellites and mt control region sequences. This suggested positive selection on ATP6 sequences, which was confirmed by several codon-based tests for one sequence site that together with a second site translated into four different amino acids. Positive selection on ND2 sequences was also confirmed by several codon-based tests. The corresponding frequencies of the two most prevalent variants at each locus varied significantly across climate regions, and our logistic general linear models of occurrence of those proteins indicated significant effects of mean annual temperature for ATP6 and mean minimum temperature of the coldest month of the year for ND2, independent of geographical location, annual precipitation, and the respective co-occurring protein at the second locus. Moreover, presence of the ancestral ATP6 protein, as inferred from phylogenetic networks, was positively affected by the simultaneous presence of the derived ND2 protein and vice versa, independent of temperature, precipitation, or geographic location. Finally, we obtained a significant coevolution signal for the ancestral ATP6 and derived ND2 sequences and vice versa. CONCLUSIONS: positive selection was strongly suggested by the population genetic approach and the codon-based tests in both mtDNA genes. Moreover, the two most prevalent proteins at the ATP6 locus were distributed at significantly varying frequencies across the study area with a significant effect of mean annual temperature on the occurrence of the ATP6 proteins independent of geographical coordinates and the co-occuring ND2 protein variant. For ND2, occurrence of the two most frequent protein variants was significantly influenced by the mean minimum temperature of the coldest month, independent of the co-occurring ATP6 protein variant and geographical coordinates. This strongly suggests direct involvement of ambient temperature in the adaptation of the studied mtOXPHOS genes.


Asunto(s)
Liebres/genética , Proteínas Mitocondriales/genética , ATPasas de Translocación de Protón Mitocondriales/genética , NADH Deshidrogenasa/genética , Selección Genética , Secuencia de Aminoácidos , Animales , Clima , Filogenia , Polimorfismo Genético , Alineación de Secuencia , Túnez
14.
Anal Bioanal Chem ; 409(12): 3261-3269, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28255921

RESUMEN

Recombinase polymerase amplification (RPA) is an elegant method for the rapid, isothermal amplification of nucleic acids. Here, we elucidate the optimal surface chemistry for rapid and efficient solid-phase RPA, which was fine-tuned in order to obtain a maximum signal-to-noise ratio, defining the optimal DNA probe density, probe-to-lateral spacer ratio (1:0, 1:1, 1:10 and 1:100) and length of a vertical spacer of the probe as well as investigating the effect of different types of lateral spacers. The use of different labelling strategies was also examined in order to reduce the number of steps required for the analysis, using biotin or horseradish peroxidase-labelled reverse primers. Optimisation of the amplification temperature used and the use of surface blocking agents were also pursued. The combination of these changes facilitated a significantly more rapid amplification and detection protocol, with a lowered limit of detection (LOD) of 1 · 10-15 M. The optimised protocol was applied to the detection of Francisella tularensis in real samples from hares and a clear correlation with PCR and qPCR results observed and the solid-phase RPA demonstrated to be capable of detecting 500 fM target DNA in real samples. Graphical abstract Relative size of thiolated lateral spacers tested versus the primer and the uvsx recombinase protein.


Asunto(s)
ADN Bacteriano/genética , Técnicas Electroquímicas/métodos , Francisella tularensis/genética , Técnicas de Amplificación de Ácido Nucleico/métodos , Animales , Sondas de ADN/análisis , Sondas de ADN/genética , ADN Bacteriano/análisis , Francisella tularensis/aislamiento & purificación , Límite de Detección , Modelos Moleculares , Conejos , Recombinasas/química , Relación Señal-Ruido , Tularemia/diagnóstico , Tularemia/microbiología , Tularemia/veterinaria
15.
Mar Drugs ; 14(2)2016 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-26907303

RESUMEN

The marine environment is an important source of structurally-diverse and biologically-active secondary metabolites. During the last two decades, thousands of compounds were discovered in marine organisms, several of them having inspired the development of new classes of therapeutic agents. Marine mollusks constitute a successful phyla in the discovery of new marine natural products (MNPs). Over a 50-year period from 1963, 116 genera of mollusks contributed innumerous compounds, Aplysia being the most studied genus by MNP chemists. This genus includes 36 valid species and should be distinguished from all mollusks as it yielded numerous new natural products. Aplysia sea hares are herbivorous mollusks, which have been proven to be a rich source of secondary metabolites, mostly of dietary origin. The majority of secondary metabolites isolated from sea hares of the genus Aplysia are halogenated terpenes; however, these animals are also a source of compounds from other chemical classes, such as macrolides, sterols and alkaloids, often exhibiting cytotoxic, antibacterial, antifungal, antiviral and/or antifeedant activities. This review focuses on the diverse structural classes of secondary metabolites found in Aplysia spp., including several compounds with pronounced biological properties.


Asunto(s)
Aplysia/metabolismo , Organismos Acuáticos/metabolismo , Productos Biológicos/aislamiento & purificación , Animales , Productos Biológicos/farmacología , Descubrimiento de Drogas/métodos , Humanos , Moluscos/metabolismo , Metabolismo Secundario
16.
Mol Ecol ; 23(18): 4617-30, 2014 09.
Artículo en Inglés | MEDLINE | ID: mdl-25113393

RESUMEN

Hybridization drives the evolutionary trajectory of many species or local populations, and assessing the geographic extent and genetic impact of interspecific gene flow may provide invaluable clues to understand population divergence or the adaptive relevance of admixture. In North America, hares (Lepus spp.) are key species for ecosystem dynamics and their evolutionary history may have been affected by hybridization. Here we reconstructed the speciation history of the three most widespread hares in North America - the snowshoe hare (Lepus americanus), the white-tailed jackrabbit (L. townsendii) and the black-tailed jackrabbit (L. californicus) - by analysing sequence variation at eight nuclear markers and one mitochondrial DNA (mtDNA) locus (6240 bp; 94 specimens). A multilocus-multispecies coalescent-based phylogeny suggests that L. americanus diverged ~2.7 Ma and that L. californicus and L. townsendii split more recently (~1.2 Ma). Within L. americanus, a deep history of cryptic divergence (~2.0 Ma) was inferred, which coincides with major speciation events in other North American species. While the isolation-with-migration model suggested that nuclear gene flow was generally rare or absent among species or major genetic groups, coalescent simulations of mtDNA divergence revealed historical mtDNA introgression from L. californicus into the Pacific Northwest populations of L. americanus. This finding marks a history of past reticulation between these species, which may have affected other parts of the genome and influence the adaptive potential of hares during climate change.


Asunto(s)
ADN Mitocondrial/genética , Evolución Molecular , Especiación Genética , Liebres/genética , Animales , Núcleo Celular/genética , Flujo Génico , Genética de Población , Liebres/clasificación , Hibridación Genética , Modelos Genéticos , Datos de Secuencia Molecular , América del Norte , Noroeste de Estados Unidos , Filogenia , Análisis de Secuencia de ADN
17.
J Appl Toxicol ; 34(3): 289-95, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23620197

RESUMEN

Cadmium occurs naturally in the environment and as an anthropogenic pollutant. Exposure to low concentrations of cadmium is inevitable and may produce toxic effects. Another important aspect of cadmium toxicity is its interaction, often antagonistic, with essential elements such as selenium. The aim of this study was to highlight the risks of long-term exposure to low cadmium concentrations, using a scientific and chemical approach and hares (Lepus europaeus Pallas) as model organisms in a field study. Two study areas were monitored. Levels of cadmium and selenium were quantified in the organs of hares, the expression of metallothioneins I + II and the products of lipid peroxidation were determined. The median cadmium concentrations (wet weight) in the muscle, liver, kidney and brain of hares from an exposed group ranged from 0.033 to 0.037, 0.763 to 1.054, 3.090 to 16.594 and 0.016 to 0.087 µg g(-1), respectively; whereas, the median selenium concentrations (wet weight) ranged from 0.100 to 0.108, 0.153 to 0.332, 0.677 to 0.701 and 0.078 to 0.116 µg g(-1), respectively. Expression of the metallothioneins I + II proteins was observed in tissues. Lipid peroxidation (LPO) levels, measured as malondialdehyde (MDA) equivalents, increased with the cadmium concentration. Further research on long-term exposure to low concentrations of cadmium in the environment is needed.


Asunto(s)
Cadmio/toxicidad , Contaminantes Ambientales/toxicidad , Liebres/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Metalotioneína/biosíntesis , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Cadmio/farmacocinética , Croacia , Relación Dosis-Respuesta a Droga , Monitoreo del Ambiente , Contaminantes Ambientales/farmacocinética , Riñón/efectos de los fármacos , Riñón/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Malondialdehído/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Especificidad de Órganos , Selenio/metabolismo , Factores de Tiempo , Distribución Tisular
18.
J Vet Diagn Invest ; 36(5): 599-616, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39108102

RESUMEN

Nematode, cestode, protozoan, microsporidian, and pentastomid parasites affect domesticated and wild rabbits, hares, and jackrabbits of the genera Brachylagus, Lepus, Oryctolagus, Pentalagus, and Sylvilagus. Some endoparasite infections are of limited or no significance, whereas others have potentially profound consequences. Accurate identification of endoparasites of rabbits, hares, and jackrabbits is an important facet of the work of veterinary pathologists engaged in lagomorph pathology. Here I review endoparasites from the pathologist's perspective, focusing on pathogenesis, lesions, and implications of infection. Stomach nematodes Graphidium strigosum and Obeliscoides cuniculi are infrequently pathogenic but may cause gastritis and gastric mucosal thickening. Nematodes Passalurus ambiguus, Protostrongylus spp., Trichostrongylus spp., and Trichuris spp. are rarely associated with disease. Adult Capillaria hepatica (syn. Calodium hepaticum) nematodes and non-embryonated eggs cause granulomatous hepatitis in wild Oryctolagus cuniculus and Lepus europaeus, resulting in multifocal, off-white, hepatic lesions, which may be misdiagnosed as hepatic eimeriosis. When the rabbit is an intermediate host for carnivore cestodes, the space-occupying effects of Cysticercus pisiformis and Coenurus serialis may have pathologic consequences. Eimeria stiedai is a major cause of white-spotted liver in O. cuniculus, particularly in juveniles. Enteric coccidiosis is a noteworthy cause of unthriftiness in young animals, and frequently manifests as diarrhea with grossly appreciable multifocal off-white intestinal lesions. O. cuniculus is the natural host for the zoonotic microsporidian Encephalitozoon cuniculi. Infection may be acute and focused mainly on the kidneys, or it may follow a chronic disease course, frequently with neurologic lesions. A latent carrier status may also develop.


Asunto(s)
Liebres , Animales , Conejos/parasitología , Liebres/parasitología , Enfermedades Parasitarias en Animales/parasitología , Enfermedades Parasitarias en Animales/patología , Infecciones por Nematodos/veterinaria , Infecciones por Nematodos/patología , Infecciones por Nematodos/parasitología
19.
J Fungi (Basel) ; 10(5)2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38786710

RESUMEN

Despite its ubiquitous infectivity to mammals with strong host specificity, our current knowledge about Pneumocystis has originated from studies of merely 4% of extant mammalian species. Further studies of Pneumocystis epidemiology across a broader range of animal species require the use of assays with high sensitivity and specificity. To this end, we have developed multiple universal Pneumocystis primers targeting different genetic loci with high amplification efficiency. Application of these primers to PCR investigation of Pneumocystis in free-living hares (Lepus townsendii, n = 130) and rabbits (Oryctolagus cuniculus, n = 8) in Canada revealed a prevalence of 81% (105/130) and 25% (2/8), respectively. Genotyping analysis identified five and two variants of Pneumocystis from hares and rabbits, respectively, with significant sequence divergence between the variants from hares. Based on phylogenetic analysis using nearly full-length sequences of the mitochondrial genome, nuclear rRNA operon and dihydropteroate synthase gene for the two most common variants, Pneumocystis in hares and rabbits are more closely related to each other than either are to Pneumocystis in other mammals. Furthermore, Pneumocystis in both hares and rabbits are more closely related to Pneumocystis in primates and dogs than to Pneumocystis in rodents. The high prevalence of Pneumocystis in hares (P. sp. 'townsendii') suggests its widespread transmissibility in the natural environment, similar to P. oryctolagi in rabbits. The presence of multiple distinct Pneumocystis populations in hares contrasts with the lack of apparent intra-species heterogeneity in P. oryctolagi, implying a unique evolution history of P. sp. 'townsendii' in hares.

20.
Res Vet Sci ; 166: 105093, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37980815

RESUMEN

Wild lagomorphs can act as reservoirs of several pathogens of public and animal health concern. However, the number of studies assessing the presence of Anaplasma spp. in these species is scarce. The aim of the present study was to molecularly identify Anaplasma spp. in wild rabbits (Oryctolagus cuniculus) and Iberian hares (Lepus granatensis) from Southern Spain and assess their epidemiological role in the maintenance of the bacterium. During 2017-2021, spleen samples of 394 wild rabbits and 145 Iberian hares were collected. Anaplasma DNA was detected using different PCR assays (16S rRNA and groEL) and phylogenetic analyses were carried out by Bayesian approach. The possible influence of lagomorph species, age and sex on the prevalence of Anaplasma spp. was evaluated by a multiple logistic regression model. The 9.4% of the rabbits were positive to Anaplasma bovis, but all the hares were negative. No significant differences were found in Anaplasma spp. prevalence regarding to age or sex. This is the first report of A. bovis in lagomorphs from Europe. The phylogenetic analysis of A. bovis confirms the existence of different clusters suggesting the existence of several lineages. In addition, a high divergence of nucleotide identity was observed within the lineage 4, which could result in the under-detection of some strains when using A. bovis-specific PCR, hindering its detection and characterization. Since this analysis is based on a limited number of nucleotide bases and sequences, more studies are needed for further characterize A. bovis, as well as its relationship with other Anaplasma spp.


Asunto(s)
Liebres , Lagomorpha , Animales , Conejos , España/epidemiología , Lagomorpha/genética , Filogenia , ARN Ribosómico 16S/genética , Teorema de Bayes , Anaplasma/genética , Nucleótidos
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