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1.
Parasitol Int ; 74: 101998, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31634630

RESUMO

Moniezia expansa and M. benedeni are two common tapeworm species of domestic ruminants over the world. However, their morphological and molecular data are available for limited specimens from a few countries. In the present study, we compared morphological characteristics of these two species collected from goats and cattle in northern Vietnam and analyzed their phylogenetic relationship based on the 5.8S and second internal transcribed spacer (ITS2) of nuclear ribosomal DNA and the mitochondrial cytochrome c oxidase subunit I gene (cox1). The two species are clearly distinguishable from one another not only in the morphological appearance of the interproglottidal glands but also in the gross appearance of mature and gravid proglottids. Molecular analyses revealed that the 5.8S-ITS2 sequences of Vietnamese M. expansa were highly similar (99.7%) to the sequences from Japan and India, and made a common clade, which was clearly distinct from M. benedeni of Vietnam. For cox1 sequences, Vietnamese M. expansa showed a high similarity to and were grouped with the sequences from Ethiopia and some sequences from Senegal and China to make a common clade, which was separated from the remaining clades of Senegal and China. The cox1 sequences of M. benedeni from China, Vietnam, and Senegal were far distant (10.0-15.9%) from each other. The results of this study suggest that more sequence data of Moniezia species with details of morphological features from various geographical locations should be obtained to clarify the taxonomic status of Moniezia species.


Assuntos
Bovinos/parasitologia , Cestoides/anatomia & histologia , Cestoides/classificação , Infecções por Cestoides/veterinária , Cabras/parasitologia , Animais , Animais Domésticos/parasitologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Infecções por Cestoides/epidemiologia , DNA Espaçador Ribossômico/genética , Genes Mitocondriais , Geografia , Doenças das Cabras/epidemiologia , Doenças das Cabras/parasitologia , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie , Vietnã/epidemiologia
2.
Zootaxa ; 4609(2): zootaxa.4609.2.5, 2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31717108

RESUMO

Five new species of Acanthobothrium Blanchard, 1848 are described from Gymnura cf. poecilura from the Gulf of Oman and Persian Gulf. They all belong to the Category 1 and can be differentiated from all congeners by a combination of characters, including marginal lappets on the bothridial rim, the lack of spinitrich microtriches on the proximal bothridial surfaces, the position of the genital pore in the posterior one fifth of the proglottid, the direction of the cirrus sac parallel and clinging to the ovarian lobe, the lack of post-vaginal testes, and the interruption of the vitelline follicles by the ovary. The five new species are morphologically similar to each other but differ among each other in their cephalic peduncle length, proglottid and testes number, and the apolysis status. The most similar species to this new group is Acanthobothrium fogeli Gloldstein, 1964 from the Gulf of Mexico. The new species differ from A. fogeli by the muscular pad size, cephalic peduncle length and having marginal lappets on the bothridial rim. the species of Acanthobothrium occurs in three families of elasmobranchs in the Gulf of Oman and Persian Gulf (Dasyatidae, Rhynchobatidae and Gymnuridae). The true identity of many hosts in the region is ambiguous. Therefore, we designated the sampled elasmobranch as G cf. poecilura in accordance to the previously molecular study on a few individuals from the region.


Assuntos
Borboletas , Cestoides , Infecções por Cestoides , Elasmobrânquios , Doenças dos Peixes , Animais , Feminino , Golfo do México , Oceano Índico , Omã
3.
Parasitol Res ; 118(12): 3543-3548, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31691856

RESUMO

Paranoplocephala omphalodes is a widespread parasite of voles. Low morphological variability within the genus Paranoplocephala has led to erroneous identification of P. omphalodes a wide range of definitive hosts. The use of molecular methods in the earlier investigations has confirmed that P. omphalodes parasitizes four vole species in Europe. We studied the distribution of P. omphalodes in Russia and Kazakhstan using molecular tools. The study of 3248 individuals of 20 arvicoline species confirmed a wide distribution of P. omphalodes. Cestodes of this species were found in Microtus arvalis, M. levis, M. agrestis, Arvicola amphibius, and also in Chionomys gud. Analysis of the mitochondrial gene cox1 variability revealed a low haplotype diversity in P. omphalodes in Eurasia.


Assuntos
Arvicolinae/parasitologia , Cestoides/isolamento & purificação , Infecções por Cestoides/veterinária , Doenças dos Roedores/parasitologia , Animais , Arvicolinae/classificação , Cestoides/classificação , Cestoides/genética , Cestoides/fisiologia , Infecções por Cestoides/parasitologia , Genes Mitocondriais , Especificidade de Hospedeiro , Cazaquistão , Filogenia , Federação Russa
4.
Parasitol Res ; 118(12): 3337-3347, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31664517

RESUMO

The Amazon represents one of the most complex biomes in the world; however, the temporal variations in parasite community structure of fishes inhabiting this region remain poorly understood. Therefore, processes generating such variations are still unknown. The present study evaluated the long-term temporal variation of community structure of metazoan parasites of Pimelodus blochii collected in Iaco River, State of Acre (Southwestern Brazilian Amazon). A total of 196 parasites were collected over a 6-year period (2012-2017). Twenty-four different taxa of parasites were found, of which 5 Monogenea, 11 Nematoda, 3 Digenea, 1 Acanthocephala, 1 Cestoda, and 3 Crustacea. The overall species richness ranged from 4 in 2012 to 17 in 2016, in which nematodes (larvae and adults) showed higher numerical dominance, diversity, and species richness. However, the annual species richness was similar between the study years, except in 2016, where it showed a distinctly higher value. The overall parasite diversity was also different in 2012 and 2016, whereas the overall abundance differed in 2013 and 2017. The prevalence and abundance of some infracommunities of parasites varied over time. The temporal changes in the parasite community structure of P. blochii are probably related to variations in host-related features, i.e., body size and shift in diet composition as well as to the occurrence of parasites with distinct life history and biology (mainly monogeneans, digeneans, and nematodes). This is the first evaluation of a long-term temporal variation in the structure of the parasite community in fish from the Amazon.


Assuntos
Acantocéfalos/isolamento & purificação , Peixes-Gato/parasitologia , Cestoides/isolamento & purificação , Doenças dos Peixes/parasitologia , Nematoides/isolamento & purificação , Trematódeos/isolamento & purificação , Acantocéfalos/classificação , Animais , Brasil/epidemiologia , Cestoides/classificação , Crustáceos/classificação , Ecossistema , Larva , Nematoides/classificação , Doenças Parasitárias em Animais/epidemiologia , Rios/parasitologia , Trematódeos/classificação
5.
Parasitol Res ; 118(11): 3129-3137, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31612284

RESUMO

The metacestodes of aploparaksid cestode Wardium cirrosa Krabbe, 1869 parasitic in gulls were found in polychaetes of the family Nereidae collected off the Black Sea coast, Ukraine. Two species of polychaetes, Hediste diversicolor (prevalence 5.3%; intensity 1-3 specimens) and Neanthes succinea (prevalence 9.9%; intensity 1-39 specimens), were infected with cysticercoids that were observed either individually or in accumulations. The preliminary identification of the material based on morphological characteristics was later confirmed by experimental infection of the definitive host, Larus cachinnans (Charadriiformes: Laridae) with metacestodes, and by the identity of the partial 28S rDNA sequences of cysticercoids and experimentally obtained adults. Although previous studies suggested freshwater leeches as the intermediate host for W. cirrosa, our study provides the evidence for marine polychaetes to serve as intermediate hosts. This study is the first to present the morphological characteristics of metacestodes of W. cirrosa in addition to molecular data for this species, as well as reporting the possibility of several cysticercoids developing from a single oncosphere. Morphology of the adult specimens obtained in the experiment was compared with adults of W. cirrosa previously collected from L. cachinnans in Ukraine. The results of our study suggest that further research focused on the elucidation of the life cycles of cestodes within the genus Wardium should consider marine invertebrates as potential intermediate hosts.


Assuntos
Cestoides/fisiologia , Poliquetos/parasitologia , Animais , Cestoides/anatomia & histologia , Cestoides/classificação , DNA de Helmintos , DNA Ribossômico , Feminino , Interações Hospedeiro-Parasita , Estágios do Ciclo de Vida , Masculino , Ucrânia
6.
Dokl Biol Sci ; 487(1): 101-104, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31571075

RESUMO

In this ecological and physiological study of the common eider (Somateria mollissima) nesting on the coast of Eastern Murman, the species composition of the bird helminth fauna, as well as the infection quantitative parameters, were determined. The common eider small intestine proved to be infected with trematodes of the genus Microphallus; three species of cestodes, namely, Lateriporus teres (Cestoda: Dilepididae), Fimbriarioides intermedia (Cestoda: Hymenolepididae), and Microsomacanthus diorchis (Cestoda: Hymenolepididae); and one species of acanthocephalan, Polymorphus phippsi (Palaeacanthocephala: Polymorphidae). At the sites of F. intermedia and M. diorchis locations within the intestine, the protease activity was reduced while in the foci infected with acanthocephalan P. phippsi, it was, on the contrary, increased. Glycosidase activity in the intestinal mucosa was reduced as compared to the control in birds infected by the cestodes M. diorchis. Hematological indices of the infected individuals were higher than the control parameters.


Assuntos
Anseriformes/parasitologia , Doenças das Aves/parasitologia , Helmintíase/parasitologia , Intestino Delgado/parasitologia , Acantocéfalos/patogenicidade , Animais , Proteínas Aviárias/metabolismo , Doenças das Aves/metabolismo , Cestoides/patogenicidade , Glicosídeo Hidrolases/metabolismo , Helmintíase/metabolismo , Mucosa Intestinal/metabolismo , Peptídeo Hidrolases/metabolismo , Trematódeos/patogenicidade
7.
Dokl Biol Sci ; 487(1): 108-111, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31571077

RESUMO

Progressive expansion of the most hazardous human parasitoses caused by trematodes, cestodes and nematodes has been found on the south of the Russian Far East. Decelerating expansion of the trematode Clonorchis sinensis, an agent of clonorchiasis towards the southern Primorye Territory from the Amur River basin, that began 10-15 years ago, was revealed. A prognosis was made on the activation of the natural foci of clonorchiasis and paragonimiasis. Circulation possibilities are discussed of the highly pathogenic trematode Pagonimus heterotremusar in the South Asian regional ecosystems. Our experiments showed that the freshwater gastropods of the Parajuga genus from the Amur River basin and those of Stenothyra genus from Primorsky Territory were resistant to this trematode infection. Nevertheless, this does not exclude the possibility of this parasite penetration into the Far East region via infection of the local gastropods of other genera.


Assuntos
Reservatórios de Doenças/parasitologia , Helmintíase/parasitologia , Animais , Canidae/parasitologia , Cestoides/patogenicidade , Clima , Demografia/estatística & dados numéricos , Felidae/parasitologia , Peixes/parasitologia , Helmintíase/epidemiologia , Helmintíase/transmissão , Humanos , Moluscos/parasitologia , Nematoides/patogenicidade , Sibéria , Trematódeos/patogenicidade
8.
BMC Infect Dis ; 19(1): 854, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619188

RESUMO

BACKGROUND: Taenia hydatigena, T. multiceps, T. pisiformis, and Dipylidium caninum are four common large and medium-sized tapeworms parasitizing the small intestine of dogs and other canids. These parasites cause serious impact on the health and development of livestock. However, there are, so far, no commercially available molecular diagnostic kits capable of simultaneously detecting all four parasites in dogs. The aim of the study was therefore to develop a multiplex PCR assay that will accurately detect all four cestode infections in one reaction. METHODS: Specific primers for a multiplex PCR were designed based on corresponding mitochondrial genome sequences, and its detection limit was assessed by serial dilutions of the genomic DNAs of tapeworms examined. Furthermore, field samples of dog feces were tested using the developed assay. RESULTS: A multiplex polymerase chain reaction (PCR) assay was developed based on mitochondrial DNA (mtDNA) that accurately and simultaneously identify four cestode species in one reaction using specific fragment sizes of 592, 385, 283, and 190 bp for T. hydatigena, T. multiceps, T. pisiformis, and D. caninum, respectively. The lowest DNA concentration detected was 1 ng for T. hydatigena, T. multiceps and T. pisiformis, and 0.1 ng for D. caninum in a 25 µl reaction system. This assay offers high potential for the rapid detection of these four tapeworms in host feces simultaneously. CONCLUSIONS: This study provides an efficient tool for the simultaneous detection of T. hydatigena, T. multiceps, T. pisiformis, and D. caninum. The assay will be potentially useful in epidemiological studies, diagnosis, and treatment of these four cestodes infections during prevention and control program.


Assuntos
Cestoides , Infecções por Cestoides , Técnicas Microbiológicas/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Animais , Cestoides/genética , Cestoides/isolamento & purificação , Infecções por Cestoides/diagnóstico , Infecções por Cestoides/parasitologia , Cães
9.
Ann Parasitol ; 65(3): 251-255, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31599541

RESUMO

During the parasitological examination of 288 wild ducks from north-western Poland, 18 tapeworms were found in the intestines (jejunum, ileum and rectum) of six birds, which, based on the structure of the scolex, internal organs and the presence of cirrus with an internal additional sac, were determinated as Dicranotaenia stenosacculata Macko, 1988. Tapeworms were found in two young females Bucephala clangula, one young female Aythya marila as well as two adult males Aythya fuligula. The aim of the study was to present the morphological and ecological characteristics of the species, recently discovered for the first time in the fauna of Poland.


Assuntos
Doenças das Aves , Cestoides , Infecções por Cestoides , Patos , Animais , Doenças das Aves/parasitologia , Cestoides/anatomia & histologia , Cestoides/fisiologia , Infecções por Cestoides/parasitologia , Infecções por Cestoides/veterinária , Patos/parasitologia , Feminino , Masculino , Polônia
10.
Biol Lett ; 15(9): 20190495, 2019 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-31506036

RESUMO

Compared with uninfected individuals, infected animals can exhibit altered phenotypes. The changes often appear beneficial to parasites, leading to the notion that modified host phenotypes are extended parasite phenotypes, shaped by parasite genes. However, the phenotype of a parasitized individual may reflect parasitic manipulation, host responses to infection or both, and disentangling the contribution of parasite genes versus host genes to these altered phenotypes is challenging. Using a tapeworm (Schistocephalus solidus) infecting its copepod first intermediate host, I performed a full-factorial, cross-infection experiment with five host and five parasite genotypes. I found that a behavioural trait modified by infection, copepod activity, was affected by both host and parasite genotype. There was no clear evidence for host genotype by parasite genotype interactions. Several observations indicated that host behaviour was chiefly determined by parasite genes: (i) all infected copepods, regardless of host or parasite genotype, exhibited behavioural changes, (ii) parasitism reduced the differences among copepod genotypes, and (iii) within infected copepods, parasite genotype had twice as large an effect on behaviour as host genotype. I conclude that the altered behaviour of infected copepods primarily represents an extended parasite phenotype, and I discuss how genetic variation in parasitic host manipulation could be maintained.


Assuntos
Cestoides , Copépodes , Parasitos , Animais , Genótipo , Interações Hospedeiro-Parasita
11.
Bull Environ Contam Toxicol ; 103(5): 670-675, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31471657

RESUMO

Here we evaluate the potential of heavy metal accumulation of Proteocephalus macrophallus parasitizing the Butterfly Peacock Bass (Cichla ocellaris). A total of 19 fish specimens were collected. From the hosts, samples of intestine, liver, muscle, and parasites were taken. Heavy metal concentrations (Al, As, Ba, Cd, Cr, Fe, Hg, Mg, Mn, Ni, Pb, Ti, and Zn) were obtained using Atomic Absorption Spectrometry. All analyzed elements was found in higher concentrations in the parasites comparing to its host tissues. The bioconcentration factors were higher in the intestine, varying between 5.91 (Ti) to 8.00 (Ba), followed by the muscle, 1.88 (Mg) to 6.39 (Zn), and liver, 1.67 (Al) to 2.02 (Ba). These results show that at the infection site heavy metal concentrations are reduced, since the elements are absorbed directly from the intestinal wall by the parasites. In general, P. macrophallus presents a reasonable capacity of metal accumulation comparing to its hosts.


Assuntos
Cestoides/metabolismo , Ciclídeos/parasitologia , Monitoramento Ambiental/métodos , Intestinos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Brasil , Cestoides/isolamento & purificação , Alimentos Marinhos/análise
12.
Parasitol Res ; 118(10): 2789-2800, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31485863

RESUMO

An original cytogenetic study combining classical karyotype analysis and modern fluorescence in situ hybridization using telomeric (TTAGGG)n and ribosomal sequences (18S rDNA) was performed in Khawia abbottinae (Cestoda, Caryophyllidea), a parasite of Chinese false gudgeon (Abbottina rivularis) from China. Analyses based on conventional Giemsa staining, DAPI, YOYO-1 dye, and silver (Ag) staining were also carried out. The karyotype is composed of eight pairs of metacentric and telocentric chromosomes (2n = 16, n=5m + 3t). Constitutive heterochromatin was mainly positioned at pericentromeric regions, and telomeric sequences (TTAGGG)n were restricted to the end of all chromosomes. In mitotic preparations stained with Giemsa, both homologues of chromosome pair 4 showed a distinct secondary constriction. FISH with rDNA probe confirmed that this secondary constriction contains a nucleolar organizer region (NOR). The process of spermatocyte meiosis and the dynamics of nucleolus degradation in dividing cell were scrutinized. The present study and its results enhance the limited knowledge on basic karyotype characteristics and 18S rDNA clusters location in caryophyllidean tapeworms.


Assuntos
Cestoides/genética , Cromossomos/genética , DNA Ribossômico/genética , Telômero/genética , Animais , Cestoides/classificação , Cestoides/isolamento & purificação , China , Cyprinidae/genética , DNA de Helmintos/genética , Proteínas de Helminto/genética , Heterocromatina/genética , Hibridização in Situ Fluorescente , Cariótipo , Cariotipagem , Ribossomos/genética
13.
Parasitol Res ; 118(10): 2863-2875, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31399870

RESUMO

A fundamental aim of parasite ecology is to understand the mechanisms behind spatial variation in diversity and structure of parasite assemblages. To understand the contribution of individual parasite species and their assemblages to spatial variation in parasite communities, we examined species contributions to beta diversity (SCBD) and local contributions to beta diversity (LCBD) of parasitic gastrointestinal helminths (nematodes and cestodes) in two closely related rodents, Rhabdomys dilectus and Rhabdomys pumilio, from 20 localities across South Africa. Although the two Rhabdomys spp. are morphologically similar, they differ substantially in body size, habitat preference, and sociality. We asked whether the variation in life history traits and infection parameters are associated with SCBD of helminths and whether variation in environmental factors, host population density, and species richness of host communities are associated with LCBD of component assemblages of helminths. We also considered spatial factors to test whether LCBD of helminth assemblages demonstrate geographic structure. We found that the contribution of helminth species parasitic in both hosts to beta diversity significantly increased with characteristic prevalence of these species, whereas mean abundance, type of life cycle, and location in the host's gut had no effect on SCBD. The LCBD of helminth assemblages showed a significant positive correlation with environmental factors in both host species. Our results suggest that predictors of variation in SCBD and LCBD may substantially differ between parasites with different infection parameters and/or parasite communities at different hierarchical scales.


Assuntos
Cestoides/isolamento & purificação , Infecções por Cestoides/epidemiologia , Trato Gastrointestinal/parasitologia , Murinae/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/epidemiologia , Animais , Cestoides/classificação , Infecções por Cestoides/parasitologia , Infecções por Cestoides/veterinária , Ecologia , Ecossistema , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Especificidade de Hospedeiro , Estágios do Ciclo de Vida , Nematoides/classificação , Infecções por Nematoides/parasitologia , Infecções por Nematoides/veterinária , Densidade Demográfica , Prevalência , África do Sul/epidemiologia
14.
Parasit Vectors ; 12(1): 390, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31382993

RESUMO

BACKGROUND: Moniezia expansa (Cyclophyllidea: Anoplocephalidae) is a large species of tapeworm that occurs in sheep and cattle and inhabits the small intestine, causing diarrhea and weight declines, leading to stockbreeding losses. Interestingly, the body fat percentage of M. expansa, which lacks the ability to synthesize fatty acids, is as high as 78% (dry weight) and all of the proglottids of M. expansa exhibit a dynamic developmental process from top to bottom. The aim of this paper is to identify the molecular basis of this high body fat percentage, the dynamic expression of developmental genes and their expression regulation patterns. RESULTS: From 12 different proglottids (four sections: scolex and neck, immature, mature and gravid with three replicates), 13,874 transcripts and 680 differentially expressed genes (DEGs) were obtained. The gene expression patterns of the scolex and neck and immature proglottids were very similar, while those of the mature and gravid proglottids differed greatly. In addition, 13 lipid transport-related proteins were found in the DEGs, and the expression levels showed an increasing trend in the four proglottid types. Furthermore, it was shown that 33 homeobox genes, 9 of which were DEGs, had the highest expression in the scolex and neck section. The functional enrichment results of the DEGs were predominantly indicative of development-related processes, and there were also some signal transduction and metabolism results. The most striking result was the finding of Wnt signaling pathways, which appeared multiple times. Furthermore, the weighted gene co-expression networks were divided into 12 modules, of which the brown module was enriched with many development-related genes. CONCLUSIONS: We hypothesize that M. expansa uses lipid transport-associated proteins to transport lipids from the host gut to obtain energy to facilitate its high fecundity. In addition, homeobox genes and Wnt signaling pathways play a core role in development and regeneration. The results promote research on the cell differentiation involved in the continuous growth and extension of body structures.


Assuntos
Tecido Adiposo/fisiologia , Cestoides/fisiologia , Regulação da Expressão Gênica , Animais , Cestoides/classificação , Cestoides/genética , Infecções por Cestoides/parasitologia , Infecções por Cestoides/veterinária , Feminino , Masculino , Ovinos/parasitologia , Via de Sinalização Wnt
15.
J Anim Ecol ; 88(12): 1986-1997, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31365124

RESUMO

Parasites are important selective agents with the potential to limit gene flow between host populations by shaping local host immunocompetence. We report on a contact zone between lake and river three-spined sticklebacks (Gasterosteus aculeatus) that offers the ideal biogeographic setting to explore the role of parasite-mediated selection on reproductive isolation. A waterfall acts as a natural barrier and enforces unidirectional migration from the upstream river stickleback population to the downstream river and lake populations. We assessed population genetic structure and parasite communities over four years. In a set of controlled experimental infections, we compared parasite susceptibility of upstream and downstream fish by exposing laboratory-bred upstream river and lake fish, as well as hybrids, to two common lake parasite species: a generalist trematode parasite, Diplostomum pseudospathaceum, and a host-specific cestode, Schistocephalus solidus. We found consistent genetic differentiation between upstream and downstream populations across four sampling years, even though the downstream river consisted of ~10% first-generation migrants from the upstream population as detected by parentage analysis. Fish in the upstream population had lower genetic diversity and were strikingly devoid of macroparasites. Through experimental infections, we demonstrated that upstream fish and their hybrids had higher susceptibility to parasite infections than downstream fish. Despite this, naturally sampled upstream migrants were less infected than downstream residents. Thus, migrants coming from a parasite-free environment may enjoy an initial fitness advantage, but their descendants seem likely to suffer from higher parasite loads. Our results suggest that adaptation to distinct parasite communities can influence stickleback invasion success and may represent a barrier to gene flow, even between close and connected populations.


Assuntos
Cestoides , Infecções por Cestoides , Doenças dos Peixes , Parasitos , Smegmamorpha , Animais , Fluxo Gênico , Interações Hospedeiro-Parasita , Lagos
16.
Rev Bras Parasitol Vet ; 28(4): 773-778, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31365718

RESUMO

The aim of the present study was to identify, through morphological and morphometric analyses, the species of trypanorhynch cestodes found as plerocerci in the intestinal serosa of Mugil liza and to determine their parasitic indices. One hundred and fifty specimens of this mullet collected off the coast of the state of Rio de Janeiro were necropsied and the trypanorhynch cestodes found were fixed and preserved as whole mounts for morphological analysis. The plerocerci were identified as Callitetrarhynchus gracilis and Pterobothrium crassicole, both with a prevalence of 0.67%, an intensity of 1 and abundance of 0.0067, in single infections. This is the first record of a trypanorhynch cestode parasitizing M. liza in Brazil. Although the parasitic indexes were low, from a hygienic-sanitary perspective the plerocerci of these species are visible to the naked eye, and thus can disgust consumers and make marketing the fish unfeasible.


Assuntos
Cestoides/anatomia & histologia , Cestoides/classificação , Peixes/parasitologia , Animais , Brasil , Cestoides/isolamento & purificação , Comércio
17.
Syst Parasitol ; 96(8): 659-672, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31468325

RESUMO

Based on morphological evaluation of type-specimens and new material collected in three species of monitor lizards (Squamata: Varanidae), the diagnosis of the monotypic Rostellotaenia Freze, 1963 (Proteocephalidae: 'Acanthotaeniinae') is amended. The genus differs from Acanthotaenia von Linstow, 1903, with which it was previously synonymised, by the shape of the scolex with a wide, dome-shaped rostellum, the posterior extent of the uterus, which does not overpass the ovarian isthmus posteriorly, well-developed retractor muscles connecting the rostellum with the neck region, absence of a well-developed, ring-like vaginal sphincter, shorter and wider proglottides, and geographical distribution (Ethiopian region only). The type- and only species, R. nilotica (Beddard, 1913), is redescribed and two new definitive hosts, Varanus albigularis Daudin and V. exanthematicus (Bosc), are reported. Host specificity of R. nilotica, which exhibits remarkable morphological variability, is stenoxenous, i.e. it occurs in several congeneric species of African monitor lizards, unlike species of Acanthotaenia, which are strictly specific (oioxenous).


Assuntos
Cestoides/classificação , Lagartos/parasitologia , Animais , Cestoides/anatomia & histologia , Filogenia , Especificidade da Espécie
18.
J Helminthol ; 94: e81, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31469060

RESUMO

Currently, descriptive information on the host range and geographic distribution of helminth parasites associated with naturally occurring rodents in South and southern Africa is scant. Therefore, we embarked on a countrywide study to: (1) identify gastrointestinal helminths and their host range, and (2) provide baseline data on the geographic distribution of helminths across the country. Altogether, 55 helminth taxa were recovered from at least 13 rodent species (n = 1030) at 26 localities across South Africa. The helminth taxa represented 25 genera (15 nematodes, nine cestodes and one acanthocephalan). Monoxenous nematodes were the most abundant and prevalent group, while the occurrence of heteroxenous nematodes and cestodes was generally lower. The study recorded several novel helminth-host associations. Single-host-species infections were common, although multiple-host-species infections by helminth species were also recorded. Monoxenous nematodes and some cestodes were recovered countrywide, whereas heteroxenous nematodes were restricted to the eastern regions of South Africa. The study highlights the as yet unexplored diversity of helminth species associated with naturally occurring rodent species and provides initial data on their geographical distribution in South Africa.


Assuntos
Biodiversidade , Cestoides/classificação , Especificidade de Hospedeiro , Nematoides/classificação , Roedores/parasitologia , Animais , Trato Gastrointestinal/parasitologia , Geografia , Helmintíase Animal/parasitologia , Interações Hospedeiro-Parasita , Infecções por Nematoides/epidemiologia , Prevalência , Doenças dos Roedores/parasitologia , Roedores/classificação , África do Sul
19.
J Helminthol ; 94: e58, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31272516

RESUMO

The order Onchoproteocephalidea (Eucestoda) was recently erected to accommodate the hook-bearing tetraphyllideans and the proteocephalideans, which are characterized by internal proglottization and a tetra-acetabulate scolex. The recognized subfamilies in the Proteocephalidae appeared to be non-monophyletic based on 28S recombinant DNA (rDNA) sequence data. Other molecular markers with higher phylogenetic resolution, such as large mitochondrial DNA fragments and multiple genes, are obviously needed. Thus the mitochondrial genome of Gangesia oligonchis, belonging to the putative earliest diverging group of the Proteocephalidae, was sequenced. The circular mitogenome of G. oligonchis was 13,958 bp in size, and contained the standard 36 genes: 22 transfer RNA genes, two rRNA genes and 12 protein-coding genes, as well as two major non-coding regions. A short NCR and a large NCR (lNCR) region were 216 bp and 419 bp in size, respectively. Highly repetitive regions in the lNCR region were detected with that of 11 repeat units. The mitogenome of G. oligonchis shared 71.1% nucleotide identity with Testudotaenia sp. WL-2016. Phylogenetic analyses of the complete mitochondrial genomes with Bayesian inference and maximum likelihood methods indicated that G. oligonchis formed a sister clade with Testudotaenia sp. WL-2016 with maximum support. The ordinal topology is (Caryophyllidea, (Diphyllobothriidea, (Bothriocephalidea, (Onchoproteocephalidea, Cyclophyllidea)))). The mitogenomic gene arrangement of G. oligonchis was identical to that of Testudotaenia sp. WL-2016. Both mitogenomic and nuclear sequence data for many more taxa are required to effectively explore the inter-relationships among the Onchoproteocephalidea.


Assuntos
Cestoides/classificação , Cestoides/genética , Genoma Mitocondrial , Filogenia , Animais , Teorema de Bayes , Peixes-Gato/parasitologia , DNA Mitocondrial/genética , Análise de Sequência de DNA
20.
Rev Bras Parasitol Vet ; 28(2): 266-282, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31271642

RESUMO

Forty specimens of the Narrowstripe cardinal fish Apogon exostigma were examined for gastrointestinal helminthes, and 62.5% were infected with a new trypanorhynchid larval cestode parasite. The morphology of its larval stage was studied based on light and scanning electron microscopy. The data revealed plerocercoid larvae characterized by a pyriform body lined with prominent microtriches; the acraspedote scolex had four overlapping bothridia; four tentacles protruded through the pars bothridialis; the armature of the tentacles was homeocanthous, homeomorphous, and consisted of falcate compact rose-thorn-shaped tentacular hooks; four oval-shaped bulbs in pars bulbosa; and short appendix at terminal end of the body. Molecular analysis of the 18S rRNA sequences verified the taxonomy of this parasite and supported its morphology. We discovered that there was a close identity (up to 87%) with alternative species obtained for comparison from GenBank. The data also showed that there were high blast scores and low divergence values between this parasite and other Tentaculariidae species. The phyletic analysis showed that parasite sequences in conjunction with existing data places this trypanorhynchid species among the Tentaculariidae. This species is deeply embedded within genus Nybelinia with close relationships to Nybelinia queenslandensis as a putative sister taxon.


Assuntos
Cestoides/isolamento & purificação , Infecções por Cestoides/parasitologia , Doenças dos Peixes/parasitologia , Perciformes/parasitologia , Animais , Cestoides/anatomia & histologia , Cestoides/classificação , Cestoides/genética , Perciformes/classificação , Filogenia , RNA Ribossômico 18S/genética
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