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1.
Parasitol Res ; 119(6): 1891-1901, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32382990

RESUMO

Amphibian populations are declining around the world, and the main reasons are the environmental changes and pathogens. However, there are few studies addressing the interaction and impact of the different pathogens that affect amphibians, such as hemoparasites. These parasites had been described as common in some amphibian species, but unfortunately, their description and characterization are unclear and scarcely spread. The objective of the present study was to evaluate the morphological and molecular characterization of hemoparasites present in vaillant's frogs. Seven frogs of Lithobates vaillanti were captured at the biological station La Florida in Tabasco, Mexico. Blood smears were performed, and results show that 100% of the animals have hemoparasites. Three types of hemoparasites were found. Eighty-five percent of the frogs were positive to Hepatozoon sp., 57% to Lankesterella sp., and 28% to Trypanosoma sp. According to the molecular analysis of the obtained sequences of Trypanosoma sp. and Hepatozoon sp., both protozoans were positioned in between the clusters of parasites of different geographical regions. Nevertheless, no species names were assigned to any of these parasites because more sequences and analysis are needed.


Assuntos
Ranidae/parasitologia , Animais , Eucoccidiida/classificação , Eucoccidiida/isolamento & purificação , Florida , México , Parasitos/classificação , Parasitos/isolamento & purificação , Trypanosoma/classificação , Trypanosoma/isolamento & purificação
2.
PLoS Negl Trop Dis ; 14(2): e0008019, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32101542

RESUMO

BACKGROUND: In China, frogs play an understudied role in the spread of human sparganosis (caused by the larval form of Spirometra). However, our knowledge about the prevalence of sparganum infection in frogs remains fragmented, and the taxonomic identification of the parasite is still controversial. METHODOLOGY/PRINCIPAL FINDINGS: The prevalence of sparganum infection in wild frogs was surveyed at 145 geographical locations from 28 of the 34 provinces/autonomous regions/municipalities in China for six years. The collected sparganum isolates from the different locations were subjected to molecular identification by a multiplex PCR assay and then were analysed with clustering analysis. In the survey, sparganum infection was found in 8 out of 13 of the collected frog species, and the most frequently infected species was Pelophylax nigromaculatus (the infection rate was up to 14.07%). Infected frogs were found in 80 of the 145 surveyed locations. The sparganum infection rates in the wild frogs in several regions of China were still high (above 10%), especially in South and Southwest China. A total of 72 spargana were selected for molecular identification, and the clustering analysis showed that sequences from the Chinese isolates were very similar to those identified as from Spirometra erinaceieuropaei. However, the taxonomy of the genus remains confused and further analysis is required. CONCLUSIONS: Eating wild frogs is associated with considerable health risks in China. Several traditional Chinese folk remedies may increase the risk of infection. The sparganum isolates in China are most likely from S. erinaceieuropaei, but new studies, especially comprehensive morphological analyses, are needed in the future.


Assuntos
Infecções por Cestoides/veterinária , Ranidae/parasitologia , Spirometra/classificação , Animais , Infecções por Cestoides/epidemiologia , Infecções por Cestoides/parasitologia , China/epidemiologia , Interações Hospedeiro-Parasita
3.
J Parasitol ; 105(5): 821-826, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31670613

RESUMO

Codonocephalus is a monotypic genus of diplostomid digeneans and is the only genus in the sub-family Codonocephalinae. The type-species Codonocephalus urniger has an unusual progenetic metacercaria that uses frogs as intermediate hosts and can use snakes as paratenic hosts. Adult C. urniger parasitize ardeid wading birds in the Palearctic. Despite the broad distribution of Codonocephalus, no DNA sequence data are currently available for the genus. In this study, we generated sequence data for nuclear ribosomal and mitochondrial DNA from progenetic metacercaria of the type-species C. urniger from marsh frog, Pelophylax ridibundus, collected in Ukraine. We used partial sequences of the nuclear ribosomal 28S gene to examine for the first time the phylogenetic position of Codonocephalus among the Diplostomoidea.


Assuntos
Filogenia , Ranidae/parasitologia , Trematódeos/classificação , Infecções por Trematódeos/veterinária , Animais , Teorema de Bayes , DNA de Helmintos/química , DNA de Helmintos/isolamento & purificação , DNA Ribossômico/química , Complexo IV da Cadeia de Transporte de Elétrons/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Estágios do Ciclo de Vida , Metacercárias/classificação , Metacercárias/genética , Microscopia Eletrônica de Varredura/veterinária , Mitocôndrias/enzimologia , RNA de Helmintos/genética , RNA Nuclear/genética , RNA Ribossômico 28S/genética , Trematódeos/genética , Trematódeos/ultraestrutura , Infecções por Trematódeos/parasitologia
4.
J Parasitol ; 105(5): 724-732, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31580787

RESUMO

In an ongoing investigation on the helminths of amphibians in southeastern Mexico, specimens of 2 undescribed species of Haematoloechus were collected from Rana brownorum. Haematoloechus ceciliae n. sp. is morphologically most similar to Haematoloechus meridionalis, but differs in the shape of the oral sucker, in the nature of the acetabulum, and in the distribution of the glandular cells in the pharyngeal region; Haematoloechus celestunensis n. sp. closely resembles Haematoloechus floedae, but differs in the form and size of the testes and measurements of acetabulum. COI and 28S DNA sequences of both new species show high divergence compared to other species of the genus. In the phylogenetic trees, H. ceciliae appears most closely related to Haematoloechus danbrooksi and H. celestunensis to Haematoloechus veracruzanus.


Assuntos
Ranidae/parasitologia , Trematódeos/classificação , Infecções por Trematódeos/veterinária , Animais , Sequência de Bases , DNA Ribossômico/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Pulmão/parasitologia , México , Mitocôndrias/enzimologia , Filogenia , Prevalência , RNA Ribossômico 28S/genética , Alinhamento de Sequência/veterinária , Trematódeos/anatomia & histologia , Trematódeos/genética , Trematódeos/isolamento & purificação , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia
5.
Environ Pollut ; 251: 600-608, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31108293

RESUMO

Changing light conditions due to human activities represents an important emerging environmental concern. Although changes to natural light conditions can be independently detrimental, in nature, organisms commonly face multiple stressors. To understand the consequences of altered light conditions, we exposed a model amphibian (wood frog; Lithobates sylvaticus) to a control and two anthropogenic light conditions: intensified daytime illuminance and artificial light at night - ALAN (intensified daytime illuminance + extended photoperiod). We measured (1) metrics of fitness (hatching success as well as survival to, size at, and time to metamorphosis) (2) susceptibility (time to death) to a commonly co-occurring anthropogenic stressor, road salt (NaCl) and (3) susceptibility (infection load) to a common parasite (trematode). We also explored behavioral (swimming activity) and physiological (baseline corticosterone (CORT) release rates) changes induced by these light conditions, which may mediate changes in the other measured parameters. We found that both intensified daytime illuminance and ALAN reduced hatching success. In contrast, for amphibians that successfully hatched, neither treatment affected amphibian survival or time to metamorphosis but individuals exposed to ALAN were larger at metamorphosis. The light treatments also had marginal effects; individuals in ALAN treatments were more susceptible to NaCl and trematodes. Finally, tadpoles exposed to ALAN moved significantly less than tadpoles in the control and intensified daytime illuminance treatments, while light had no effect on CORT release rate. Overall, changes in light conditions, in particular ALAN, significantly impacted an amphibian model in laboratory conditions. This work underscores the importance of considering not only the direct effects of light on fitness metrics but also the indirect effects of light with other abiotic and biotic stressors. Anthropogenic-induced changes to light conditions are expected to continue increasing over time so understanding the diverse consequences of shifting light conditions will be paramount to protecting wildlife populations.


Assuntos
Larva/efeitos da radiação , Luz , Metamorfose Biológica/efeitos da radiação , Fotoperíodo , Ranidae/crescimento & desenvolvimento , Trematódeos/crescimento & desenvolvimento , Animais , Corticosterona/metabolismo , Humanos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Larva/parasitologia , Ranidae/metabolismo , Ranidae/parasitologia
6.
Parasitology ; 146(7): 903-910, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30816081

RESUMO

Mesomycetozoean-induced infections (order Dermocystida, genus Amphibiocystidium) in European and North American amphibians are causing alarm. To date, the pathogenicity of these parasites in field conditions has been poorly studied, and demographic consequences on amphibian populations have not been explored. In this study, an Amphibiocystidium sp. infection is reported in a natural population of the Italian stream frog (Rana italica) of Central Italy, over a 7-year period from 2008 to 2014. Light and electron microscope examinations, as well as partial 18S rDNA sequence analysis were used to characterize the parasite. Moreover, a capture-mark-recapture study was conducted to assess the frog demographics in response to infection. Negative effects of amphibiocystidiosis on individual survival and population fitness were absent throughout the sampling period, despite the high estimates of disease prevalence. This might have been due to resistance and/or tolerance strategies developed by the frogs in response to the persistence of Amphibiocystidium infection in this system. We hypothesized that in the examined R. italica population, amphibiocystidiosis is an ongoing endemic/epidemic infection. However, ecological and host-specific factors, interacting in a synergistic fashion, might be responsible for variations in the susceptibility to Amphibiocystidium infection of both conspecific populations and heterospecific individuals of R. italica.


Assuntos
Infecções por Mesomycetozoea/epidemiologia , Mesomycetozoea/patogenicidade , Ranidae/parasitologia , Animais , Biópsia , Suscetibilidade a Doenças , Feminino , Interações Hospedeiro-Parasita , Itália/epidemiologia , Estudos Longitudinais , Masculino , Mesomycetozoea/genética , Prevalência , Rios/parasitologia , Pele/parasitologia , Pele/patologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-30502473

RESUMO

The negative effects of abiotic and biotic stressors on animal condition, physiology, behaviour, and fitness have become increasingly recognized, making it critical to understand how these may be mitigated, such as through diet. When consumed, dietary antioxidants (secondary metabolites produced by plants) provide protection from oxidative damage that can result from exposure to stressors. We examined the effects of dietary antioxidants (ß-carotene and vitamin E) on the ability of Lithobates sylvaticus (wood frog) tadpoles to overcome the detrimental effects imposed by two common environmental stressors - exposure to the herbicide atrazine or infection by a pathogenic helminth parasite (Echinostoma trivolvis). Tadpoles which were fed high concentrations of either vitamin E or ß-carotene had a greater immune response compared to those given trace diets of either compound as measured by circulating white blood cells and a phytohemaglutination assay (PHA). Similarly, tadpoles in the herbicide and parasitism treatments that were given trace antioxidant diets had significant weight loss, whereas those consuming high levels of vitamin E or ß-carotene did not. Our results suggest that dietary antioxidants, specifically ß-carotene and vitamin E, have a positive effect on tadpole immune systems and overall condition that likely allows them to better cope with natural stressors, with potential implications for their foraging behaviour.


Assuntos
Antioxidantes/farmacologia , Dieta , Exposição Ambiental , Estresse Oxidativo/efeitos dos fármacos , Ranidae/fisiologia , Animais , Atrazina/toxicidade , Helmintíase/imunologia , Helmintíase/fisiopatologia , Herbicidas/toxicidade , Larva/imunologia , Larva/fisiologia , Ranidae/crescimento & desenvolvimento , Ranidae/imunologia , Ranidae/parasitologia
8.
Vet Pathol ; 56(1): 133-142, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30236039

RESUMO

Severe Perkinsea infection (SPI) is an emerging disease of frogs responsible for mass mortalities of tadpoles across the United States. It is caused by protozoa belonging to the phylum Perkinsozoa that form a distinct group referred to as the Pathogenic Perkinsea Clade of frogs. In this work, we provide detailed description of gross and histologic lesions from 178 naturally infected tadpoles, including 10 species from 22 mortality events and 6 amphibian health monitoring studies from diverse geographic areas. On external examination, we observed abdominal distension (10, 5.6%), cutaneous erythema and petechia (3, 1.7%), subcutaneous edema (3, 1.7%), and areas of white skin discoloration (3, 1.7%). On macroscopic examination of internal organs, we found hepatomegaly (68, 38.2%), splenomegaly (51, 28.7%), nephromegaly (47, 26.4%), ascites (15, 8.4%), segmental irregular thickening and white discoloration of the intestine (8, 4.5%), pancreatomegaly (4, 2.2%), and pancreatic petechia (1, 0.6%). Histologically, over 60% of the liver (148/165, 89.7%), kidney (113/147, 76.9%), spleen (96/97, 99%), and pancreas (46/68, 67.6%) were invaded by myriad intracellular and extracellular Perkinsea hypnospore-like and trophozoite-like organisms. Numerous other tissues were affected to a lesser extent. Mild histiocytic inflammation with fewer lymphocytes or eosinophils was commonly observed in areas of infection that were not obscured by lympho-granulocytic hematopoietic tissue. In light of these observations, we suggest a logical pathogenesis sequence. Finally, we propose a "case definition" for SPI to promote standardized communication of results and prevent misdiagnosis with epidemiological and pathologically overlapping diseases such as ranavirosis.


Assuntos
Alveolados/patogenicidade , Infecções Protozoárias em Animais/patologia , Ranidae/parasitologia , Animais , Larva/parasitologia , Estudos Retrospectivos
9.
Parasitol Res ; 118(2): 663-666, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30426225

RESUMO

Torix is a leech genus containing freshwater proboscidate species, and several members of this taxon are ectoparasites specific to amphibians. Torix tukubana inhabits mountain streams in Japan, and only two frog species are known to be hosts. We collected this leech from two other amphibians, Onychodactylus japonicus (Japanese clawed salamander) and Rana ornativentris (montane brown frog), for the first time. This finding suggests that the host specificity of T. tukubana is low. The immature individuals of T. tukubana were also collected and identified based on DNA data. This is the first juvenile record of this species confirmed by its DNA barcode sequences. Several morphological characters known from large individuals and used as diagnostic characteristics in taxonomic keys were not observed in the juveniles, suggesting that these are ontogenetic traits.


Assuntos
Especificidade de Hospedeiro/fisiologia , Sanguessugas/genética , Ranidae/parasitologia , Urodelos/parasitologia , Animais , Ciclo-Oxigenase 1/genética , Água Doce/parasitologia , Japão , Sanguessugas/classificação , Filogenia
10.
Parasitol Res ; 118(2): 673-676, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30426226

RESUMO

The distribution of Alaria-spp.-mesocercariae within the host is relevant for the examination via Alaria spp. mesocercariae migration technique (AMT) regarding predilection sites and may indicate an interaction between parasite and host. Naturally Alaria-exposed frogs of Pelophylax species (n = 13) were examined for systemic distribution and localization-specific parasite density of Alaria spp. mesocercariae. The frogs were necropsied and their body was divided into the following localizations: inner organs, head, torso, forelimbs, and hind limbs. The localizations were analyzed individually and in toto using Alaria spp. mesocercariae migration technique. Our results showed neither statistical differences concerning the number of mesocercariae in the different localizations nor in respect of the rate of positive localizations. Therefore, an accumulation in a particular predilection site seems unlikely. Further research on a representative sample is necessary before final conclusions can be drawn.


Assuntos
Interações Hospedeiro-Parasita/fisiologia , Larva/crescimento & desenvolvimento , Carga Parasitária , Ranidae/parasitologia , Trematódeos/isolamento & purificação , Animais , Membro Anterior/parasitologia , Cabeça/parasitologia , Membro Posterior/parasitologia , Tronco/parasitologia
11.
J Parasitol ; 104(5): 544-549, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30011246

RESUMO

Thirty specimens of the Montezuma's frog Lithobates montezumae were collected in San Pedro Tlaltizapán, in the Nearctic-Neotropical transition zone of Mexico, in April 2013, in order to establish the helminth infracommunity structure harbored by this amphibian host. A total of 5,493 individual helminths were obtained, representing 6 species (3 trematodes and 3 nematodes). The depauperate structure of the helminth infracommunities established for the studied frogs herein (richness = 2.4; mean abundance = 183.1; Brillouin's diversity = 0.42) fits with those described for the 6 Ranidae species studied in the Nearctic. Three of the 6 species of helminths recovered are generalists, 2 of them with the highest values for prevalence ( Falcaustra mexicana) and mean abundance ( Renifer sp.). The parasite recruitment process (ingestion) determining mean richness in the helminth infracommunities studied here (ingestion) is shared with those reported for the 9 Mexican frog species for which helminthological records exist; however, in this case, mean abundance was determined by directly penetrating species. The use of aquatic habits by this anuran species likely explains why the composition of their helminth infracommunities was mainly constituted of helminths acquired in this environment (5 of 6 species). Finally, the heterogeneity of their taxonomic composition and abundance of helminth species indicate the unpredictable nature of these host-parasite associations.


Assuntos
Helmintíase Animal/parasitologia , Helmintos/classificação , Ranidae/parasitologia , Animais , Clima , Feminino , Helmintíase Animal/epidemiologia , Helmintos/crescimento & desenvolvimento , Helmintos/isolamento & purificação , Interações Hospedeiro-Parasita , Masculino , México/epidemiologia , Nematoides/classificação , Nematoides/crescimento & desenvolvimento , Nematoides/isolamento & purificação , Prevalência , Trematódeos/classificação , Trematódeos/crescimento & desenvolvimento , Trematódeos/isolamento & purificação , Clima Tropical
12.
Acta Parasitol ; 63(3): 572-585, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-29975656

RESUMO

Three species of acanthocephalans are described from fishes caught in the Pacific coast off eastern Vietnam and from amphibians in the midlands in 2016: (1) Acanthocephalus parallelcementglandatus Amin, Heckmann, Ha, 2014 (Echinorhynchidae), described from 1 male specimen is now fully described from males and females collected from 2 species of amphibians, the similar frog Hylarana attigua Inger, Orlov, Darevsky and the odorous frog Odorrana sp. Fei, Ye, Huang (Ranidae) in Huong Thuy, Hue City and Chu Yang Sin Park, central Vietnam, respectively, as well as from the needlefish Tylosurus sp. Cocco (Belonidae) in Binh Thuân in the Pacific South. The allotype female is designated. Neoechinorhynchus (N.) pennahia Amin, Ha, Ha, 2011 described from 1 female specimen is now fully described from males and females collected from the Toli shad (Chinese herring), Tenualosa toli (Valenciennes) (Clupeidae) in the Pacific north coast off Haiphong. The allotype male is designated. One specimen of Neoechinorhynchus (Neoechinorhynchus) longnucleatus Amin, Ha, Ha, 2011 is also reported from the common ponyfish, Leiognathus equulus (Forssskål) (Leiognathidae) in the Pacific south coast of Nha Trang and its ecology briefly discussed.


Assuntos
Acantocéfalos/classificação , Beloniformes/parasitologia , Doenças dos Peixes/parasitologia , Helmintíase Animal/parasitologia , Ranidae/parasitologia , Acantocéfalos/anatomia & histologia , Acantocéfalos/isolamento & purificação , Acantocéfalos/ultraestrutura , Animais , Ecologia , Feminino , Masculino , Microscopia de Força Atômica/veterinária , Oceano Pacífico , Vietnã
13.
J Wildl Dis ; 54(2): 397-399, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29261445

RESUMO

We identified Miranda's white-lipped frog ( Leptodactylus macrosternum) as a new host for chiggers ( Hannemania sp.). A total of 57 larvae of Hannemania sp. were found on 31 frogs examined from a semiarid region of northeastern Brazil.


Assuntos
Ranidae/parasitologia , Trombiculíase/veterinária , Trombiculidae , Animais , Brasil/epidemiologia , Trombiculíase/epidemiologia , Trombiculíase/parasitologia
14.
Syst Parasitol ; 95(2-3): 293-300, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29230677

RESUMO

Neocosmocercella fisherae n. sp. is the first nematode species found parasitising Phyllomedusa bicolor from the Brazilian Amazon Region. The new species has a triangular oral opening, with bi-lobed lips, and is distinguished from N. bakeri (triangular oral opening with simple lips), and from N. paraguayensis (hexagonal oral opening with bi-lobed lips). Additionally, the new species has ciliated cephalic papillae, which are absent in the other species of the genus. The reduced uterine sac and the presence of a single egg in the uterus in females are the main morphological characters that differentiate the new species from its congeners N. bakeri (8-10 eggs) and N. paraguayensis (10 eggs, based on the allotype). Additionally, the new species differs from the other two species of the genus by morphometric characters such as the size of spicules and gubernaculum in males and the vagina in females. Until now, phyllomedusid anurans are the only known hosts for the nematodes of this genus. The present work describes the third species of the genus and the first species of nematode parasitising P. bicolor.


Assuntos
Ascaridídios/anatomia & histologia , Ascaridídios/classificação , Ranidae/parasitologia , Animais , Brasil , Feminino , Intestino Grosso/parasitologia , Masculino , Especificidade da Espécie
15.
J Parasitol ; 103(6): 663-668, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28732178

RESUMO

Phenotypic plasticity is a process in which multiple phenotypes arise from 1 genotype because of environmental selection pressures. Gyrinicola batrachiensis has a heterogeneous reproductive strategy such that females reproduce either via parthogenesis with thick-shelled eggs in a single uterus or sexual reproduction with thick- and thin-shelled eggs in separate uterine horns. No evidence exists that strains of G. batrachiensis are able to switch between parthenogenetic and sexual reproduction. Thin-shelled eggs are autoinfective, and thick-shelled eggs act as transmission agents once shed into the aquatic environment. Our primary goal was to determine whether dioecious, didelphic pinworms that infect Rana sphenocephala, a slow-developing tadpole, and Osteopilus septentrionalis, a quick-developing tadpole, display reproductive plasticity with concern to thick- and thin-egg development. We performed experimental cross-infections in aquatic mesocosms to determine if dioecious, didelphic worms vary (based on tadpole host) in their ability to produce thin-shelled eggs: O. septentrionalis (hylid) egg masses were exposed to infected R. sphenocephala (ranid) tadpoles, ranid egg masses to infected hylid tadpoles, and a fully crossed infection that exposed ranid and hylid egg masses to infected tadpoles of both anuran families. Results indicated that worms reproduced via didelphic haplodiploidy in experimental ranid and hylid hosts, but that worms from hylids produced only thick-shelled eggs, which supports an intermediate reproductive strategy in O. septentrionalis. There was a significant difference in the mean intensities of ranid and hylid hosts, supporting our assertion that females infecting ranids are capable of producing autoinfective, thin-shelled eggs, and females infecting hylids do not produce such thin-shelled, autoinfective eggs because of the host microenvironment.


Assuntos
Nematoides/fisiologia , Ranidae/parasitologia , Adaptação Fisiológica , Animais , Feminino , Florida , Larva/classificação , Larva/parasitologia , Nematoides/classificação , Fenótipo , Reprodução/fisiologia
16.
Mol Phylogenet Evol ; 117: 75-82, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28606444

RESUMO

The larva of Spirometra erinaceieuropaei can parasitize humans, causing a serious parasitic zoonosis known as sparganosis. Although it is medically important, our knowledge about the phylogenetic position of S. erinaceieuropaei and its evolutionary history is fragmentary. In this study, complete mitochondrial (mt) genomes of 4 geographically distinct isolates of S. erinaceieuropaei spargana collected from 4 frog hosts (Hylarana guentheri, Rana nigromaculata, R. rugulosa, R. temporaria) were characterized using an Illumina sequencing platform. In addition, all available mt genomes of Cestoda in GenBank were included to reconstruct the phylogeny and to explore the evolutionary history of these tapeworms. The genome features of S. erinaceieuropaei contained 12 protein-coding genes (PCGs), 22 transfer RNA genes, 2 ribosomal RNA genes and 2 non-coding regions. Nucleotide sequences of mtDNA from different frog hosts were similar. Three genes, cox1, cytb and nad4, had high levels of nucleotide diversity. Phylogenetic analyses supported the sibling relationship between Bothriocephalidae and Diphyllobothriidae. Molecular dating analysis indicated that the divergence between Diphyllobothrium and Diplogonoporus started in the late Miocene. The mt genomes of S. erinaceieuropaei will serve as a useful dataset for studying the genetics and systematics of the species of Spirometra genus in particular and diphyllobothriid tapeworms in general.


Assuntos
Genoma Mitocondrial/genética , Genômica , Filogenia , Spirometra/classificação , Spirometra/genética , Animais , DNA Mitocondrial/genética , Genética Populacional , Humanos , Anotação de Sequência Molecular , Ranidae/parasitologia
17.
Aquat Toxicol ; 189: 42-49, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28582700

RESUMO

Large quantities of road salts are used for de-icing in temperate climates but often leach into aquatic ecosystems where they can cause harm to inhabitants, including reduced growth and survival. However, the implications of road salt exposure for aquatic animal susceptibility to pathogens and parasites have not yet been examined even though infectious diseases can significantly contribute to wildlife population declines. Through a field survey, we found a range of NaCl concentrations (50-560mg/L) in ponds known to contain larval amphibians, with lower levels found in sites close to gravel- rather than hard-surfaced roads. We then investigated how chronic exposure to environmentally-realistic levels of road salt (up to 1140mg/L) affected susceptibility to infection by trematode parasites (helminths) in larval stages of two amphibian species (Lithobates sylvaticus - wood frogs, and L. pipiens - northern leopard frogs) by considering effects on host anti-parasite behavior and white blood cell profiles. Wood frogs exposed to road salt had higher parasite loads, and also exhibited reduced anti-parasite behavior in these conditions. In contrast, infection intensity in northern leopard frogs had a non-monotonic response to road salts even though lymphocytes were only elevated at the highest concentration. Our results indicate the potential for chronic road salt exposure to affect larval amphibian susceptibility to pathogenic parasites through alterations of behavior and immunocompetence, with further studies needed at higher concentrations, as well as that of road salts on free-living parasite infectious stages.


Assuntos
Comportamento Animal/efeitos dos fármacos , Imunocompetência/efeitos dos fármacos , Tanques/química , Ranidae/parasitologia , Cloreto de Sódio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Ecossistema , Helmintos/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Ontário , Ranidae/imunologia , Ranidae/fisiologia , Cloreto de Sódio/análise , Poluentes Químicos da Água/análise
18.
Parasitol Res ; 116(6): 1745-1753, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28466247

RESUMO

Bioaccumulation of 13 trace elements in the livers of 38 Pelophylax sinkl. hispanicus (Ranidae) and its helminth communities were studied and compared among three sites, each with a different degree of pollution along River Neto (south Italy) during September, 2014. Trace element concentrations in water and liver were measured using inductively coupled plasma mass spectrometry. For most elements, the highest concentration was recorded in the frogs inhabiting the third site, the one with the highest degree of pollution. The trend of trace element concentration in the liver can be represented as follows: Cu > Zn > Mn > Se > Cr. Concentrations of some elements in water and liver samples were significantly different among the three sites and this is evidenced by the bioaccumulation in the frogs. Four species of helminths, all belonging to Nematoda, were found: Rhabdias sp., Oswaldocruzia filiformis (Goeze, 1782), Cosmocerca ornata (Dujarden, 1845), Seuratascaris numidica (Seurat, 1917). The parasite survey presents an important difference of prevalence and average number of helminths in frogs between the three sites. Correlating parasitological and ecotoxicological data showed a strong positive correlation between prevalence and number of parasites with some trace elements such as Mn, Co, Ni, As, Se, and Cd.


Assuntos
Monitoramento Ambiental , Nematoides/isolamento & purificação , Infecções por Nematoides/veterinária , Oligoelementos , Animais , Itália/epidemiologia , Fígado/química , Nematoides/classificação , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Ranidae/parasitologia , Fatores de Risco , Rios
19.
Syst Parasitol ; 94(5): 567-574, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28429172

RESUMO

During an inventory of the helminths of amphibians in Mexico, specimens of an undescribed species of Haematoloechus Looss, 1899 (Digenea: Haematoloechidae) were collected from the lungs of frogs of the "tarahumarae" group in western México. Haematoloechus longicollum n. sp. differs from other known species of Haematoloechus by the combination of the following characters: body elongate and slender in the preovarian region and broad and blunt in the postovarian region, ovary separated from the ventral sucker more than twice the ovary length, oral sucker to pharynx length ratio 1:0.56, oral sucker to ventral sucker length ratio 1:0.80, presence of extracaecal uterine loops, absence of longitudinal extracaecal uterine loops, ovary and testes oval.


Assuntos
Ranidae/parasitologia , Trematódeos/classificação , Animais , Pulmão/parasitologia , México , Especificidade da Espécie , Trematódeos/anatomia & histologia , Trematódeos/isolamento & purificação
20.
Acta Parasitol ; 61(4): 802-807, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27787210

RESUMO

Parasites are ubiquitous members of biotic communities. To investigate the infective status of helminth parasites in Pelophylax nigromaculatus from Shanghai, 90 frogs were collected from July 2013 to July 2014 and examined for the presence of internal parasites. Of these, 86.67% (78/90) of frogs were infected with parasites, the total helminth intensity within infected frogs ranged from 1 to 367, and the mean intensity was 28.49. The infection rates and intensities were 78.89% and 22.89 for trematodes, 50.00% and 5.24 for nematodes, 13.33% and 3.92 for cestodes, and 41.11% and 8.49 for acanthocephalas, respectively. The majority (60.04%) of parasites were parasitic in the intestine, followed by urinary bladder (24.8%) and lungs (7.38%). Based on morphological features, 13 different species of helminth, including 9 undetermined species, were identified. The infective status of different species was significantly different. The most prevalent species were Diplodiscus nigromaculati (64.44%), Diplodiscus sp. (37.78%), Pomphorhynchus sp. (35.56%), Strongyloides sp. (33.33%). The mean infection intensity of Diplorchis nigromaculatus (139.25) was higher than the others' species ranged from 3.57-14.63. This is the first reported discovery of Pomphorhynchus sp. (Pomphorhynchidae Yamaguti, 1939) in frogs from China. These data provide the foundation for further analyses of parasites in this and other species of amphibians.


Assuntos
Helmintíase Animal/parasitologia , Helmintos/isolamento & purificação , Ranidae/parasitologia , Animais , China/epidemiologia , Helmintíase Animal/epidemiologia , Helmintos/classificação
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