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1.
Braz. j. biol ; 83: e248032, 2023. graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1278557

RESUMO

Abstract A new species of nematode parasite of the subfamily Pudicinae (Heligmosomoidea: Heligmonellidae) is described from the small intestine of Proechimys simonsi (Rodentia: Echimyidae) from the locality of Nova Cintra in the municpality of Rodrigues Alves, Acre state, Brazil. The genus Pudica includes 15 species parasites of Neotropical rodents of the families Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae, and Myocastoridae. Four species of this nematode were found parasitizing three different species rodents of the genus Proechimys in the Amazon biome. Pudica wandiquei n. sp. can be differentiated from all other Pudica species by the distance between the ends of rays 6 and 8 and the 1-3-1 pattern of the caudal bursa in both lobes.


Resumo Uma nova espécie de nematódeo da subfamília Pudicinae (Heligmosomoidea: Heligmonellidae) é descrito parasitando o intestino delgado de Proechimys simonsi (Rodentia: Echimyidae) em Nova Cintra, município de Rodrigues Alves, Estado do Acre, Brasil. O gênero Pudica inclui 15 espécies parasitas de roedores Neotropicais das famílias: Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae e Myocastoridae. Destas, quatro espécies de nematódeos foram encontradas parasitando três diferentes espécies do roedor Proechimys no bioma Amazônia. Pudica wandiquei n. sp. é diferente das outras espécies de Pudica pela distância entre os raios 6 e 8 e pelo tipo da bolsa caudal, que é 1-3-1 em ambos os lados.


Assuntos
Animais , Parasitos , Trichostrongyloidea , Nematoides , Roedores , Brasil
2.
Braz. j. biol ; 83: e247913, 2023. graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1278555

RESUMO

Abstract The aim of this paper was recording the occurrence of the species Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) in lotic systems of the State of São Paulo. Specimens were collected in Sapucaí River, located in Campos do Jordão State Park. The mapping of geographical distribution of this species is of interest to public health since L. variegatus may be an intermediate host of Dioctophyme renale (Goeze, 1782) (Nematoda, Dioctophymatidae), a parasite of recognized zoonotic potential. Distribution data serves as a basis for environmental monitoring and evaluation, being essential to map possible cases of the disease (Dioctophimosis) and provide information to health professionals.


Resumo O objetivo deste trabalho foi registrar a ocorrência de Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) em um sistema lótico do Estado de São Paulo. Os espécimes foram coletados no rio Sapucaí, localizado no Parque Estadual de Campos do Jordão. O mapeamento da distribuição geográfica desta espécie é de interesse para saúde pública uma vez que L. variegatus pode ser um hospedeiro intermediário de Dioctophyme renale (Goeze, 1782) (Nematoda, Dioctophymatidae), parasito de reconhecido potencial zoonótico. Dados de distribuição servem de base para monitoramento e avaliação ambiental, sendo essenciais para mapear possíveis casos da doença (Dioctofimose) e fornecer informações para profissionais de saúde.


Assuntos
Animais , Oligoquetos , Nematoides , Brasil , Monitoramento Ambiental , Rios
3.
Braz. J. Biol. ; 83: 1-5, 2023. ilus
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-765412

RESUMO

A new species of nematode parasite of the subfamily Pudicinae (Heligmosomoidea: Heligmonellidae) is described from the small intestine of Proechimys simonsi (Rodentia: Echimyidae) from the locality of Nova Cintra in the municpality of Rodrigues Alves, Acre state, Brazil. The genus Pudica includes 15 species parasites of Neotropical rodents of the families Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae, and Myocastoridae. Four species of this nematode were found parasitizing three different species rodents of the genus Proechimys in the Amazon biome. Pudica wandiquei n. sp. can be differentiated from all other Pudica species by the distance between the ends of rays 6 and 8 and the 1-3-1 pattern of the caudal bursa in both lobes.(AU)


Uma nova espécie de nematódeo da subfamília Pudicinae (Heligmosomoidea: Heligmonellidae) é descrito parasitando o intestino delgado de Proechimys simonsi (Rodentia: Echimyidae) em Nova Cintra, município de Rodrigues Alves, Estado do Acre, Brasil. O gênero Pudica inclui 15 espécies parasitas de roedores Neotropicais das famílias: Caviidae, Ctenomyidae, Dasyproctidae, Echimyidae, Erethizontidae e Myocastoridae. Destas, quatro espécies de nematódeos foram encontradas parasitando três diferentes espécies do roedor Proechimys no bioma Amazônia. Pudica wandiquei n. sp. é diferente das outras espécies de Pudica pela distância entre os raios 6 e 8 e pelo tipo da bolsa caudal, que é 1-3-1 em ambos os lados.(AU)


Assuntos
Animais , Roedores/parasitologia , Nematoides/anatomia & histologia , Nematoides/classificação , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/veterinária
4.
Braz. J. Biol. ; 83: 1-4, 2023. mapas, ilus
Artigo em Inglês | VETINDEX, VETINDEX | ID: vti-765410

RESUMO

The aim of this paper was recording the occurrence of the species Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) in lotic systems of the State of São Paulo. Specimens were collected in Sapucaí River, located in Campos do Jordão State Park. The mapping of geographical distribution of this species is of interest to public health since L. variegatus may be an intermediate host of Dioctophyme renale (Goeze, 1782) (Nematoda, Dioctophymatidae), a parasite of recognized zoonotic potential. Distribution data serves as a basis for environmental monitoring and evaluation, being essential to map possible cases of the disease (Dioctophimosis) and provide information to health professionals.(AU)


O objetivo deste trabalho foi registrar a ocorrência de Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) em um sistema lótico do Estado de São Paulo. Os espécimes foram coletados no rio Sapucaí, localizado no Parque Estadual de Campos do Jordão. O mapeamento da distribuição geográfica desta espécie é de interesse para saúde pública uma vez que L. variegatus pode ser um hospedeiro intermediário de Dioctophyme renale (Goeze, 1782) (Nematoda, Dioctophymatidae), parasito de reconhecido potencial zoonótico. Dados de distribuição servem de base para monitoramento e avaliação ambiental, sendo essenciais para mapear possíveis casos da doença (Dioctofimose) e fornecer informações para profissionais de saúde.(AU)


Assuntos
Animais , Oligoquetos/crescimento & desenvolvimento , Nematoides/parasitologia , Zoonoses/prevenção & controle , Reservatórios de Doenças/parasitologia
5.
Ann Parasitol ; 68(1): 159-167, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35491932

RESUMO

Recently, many individuals of greater one-horned rhino (GOHR) were died with unknown reason in Chitwan National Park (CNP), Nepal. This has arisen chaos and confusion in the rhino conservation program of the country. This study was designed to determine the prevalence of gastrointestinal parasites among GOHR in the CNP. A total of 100 dung samples were collected opportunistically by the random sampling method. Dung samples were preserved in 2.5% potassium dichromate solution and analysed in the laboratory by the direct smear and concentration method (floatation and sedimentation). Eggs and larvae of gastrointestinal parasite were found in 91% examined samples. Altogether 13 different genera of parasites were identified with one protozoan i.e. Eimeria sp. (9%), nine nematodes i.e. Strongyloides sp. (65%), Ascaris sp. (16%), Haemonchus sp. (15%), Dromeostrongylus sp. (9%), Oxyuris sp. (8%), Bunostomum sp. (8%), Chabertia sp. (5%), Trichostrongylus sp. (4%) and Nematodirus sp. (2%), one cestode i.e. Anoplocephala sp. (16%) and two trematodes i.e. Paramphistomum sp. (31%) and Fasciola sp. (14%). Nematode parasites were found to be most prevalent (87% of samples) followed by trematodes (45%), cestodes (16%) and protozoans (9%). The study indicates a high prevalence of gastrointestinal parasites in the GOHR of CNP and identifies that there is need of strategic control measures to protect this endangered species from parasitic infection.


Assuntos
Helmintíase Animal , Enteropatias Parasitárias , Nematoides , Parasitos , Trematódeos , Animais , Helmintíase Animal/parasitologia , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/veterinária , Nepal/epidemiologia , Parques Recreativos , Prevalência
6.
Trop Biomed ; 39(1): 135-143, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35507936

RESUMO

Soil-transmitted helminth (STH) infections, mainly caused by Ascaris lumbricoides, Trichuris trichiura, and hookworms, are among the most common intestinal parasites that infect humans. The infections are widely distributed throughout tropical and subtropical countries, including Malaysia, particularly in underprivileged communities. Microscopic and culture techniques have been used as a gold standard for diagnostic techniques. However, these methods yield low sensitivity and specificity, laborious and time-consuming. Therefore, simple, rapid, and accurate alternative methods are needed for the simultaneous detection of STH infections. Although advanced technologies such as real-time multiplex PCR have been established, the use of this technique as a routine diagnostic is limited due to the high cost of the instrument. Therefore, a single-round multiplex conventional PCR assay for rapid detection of four STH species in the fecal sample was developed in this study. To perform the single-round multiplex PCR, each pair of species-specific primers was selected from target genes, including Ancylostoma duodenale (Internal Transcribed Spacer 2; accession No. AJ001594; 156 base pair), Necator americanus (ITS 2; accession No. AJ001599; 225 base pair), Ascaris lumbricoides (Internal Transcribed Spacer 1; accession No. AJ000895; 334 base pair) and Trichuris triciura (partial ITS 1, 5.8s rRNA and partial ITS 2; accession No. AM992981; 518 base pair). The results showed that the newly designed primers could detect the DNA of STH at low concentrations (0.001 ng/ µl) with no cross-amplification with other species. This assay enables the differentiation of single infections as well as mixed infections. It could be used as an alternative and is a convenient method for the detection of STHs, especially for the differentiation of N. americanus and A. duodenale.


Assuntos
Helmintíase , Nematoides , Animais , Ascaris lumbricoides/genética , Primers do DNA , Fezes/parasitologia , Helmintíase/diagnóstico , Humanos , Reação em Cadeia da Polimerase Multiplex/métodos , Solo/parasitologia , Trichuris/genética
7.
Trop Anim Health Prod ; 54(3): 179, 2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35511381

RESUMO

We aimed to evaluate a Brazilian commercial formulation of the fungus Duddingtonia flagrans (Bioverm®) for controlling gastrointestinal nematodes in sheep kept on native pasture in the Caatinga biome, in the semiarid region of Brazil. Twenty ewes, aged between 12 and 18 months, were divided into two groups. In the treated group, each animal received 1 g of the Bioverm® product for each 10 kg of live weight, daily, together with commercial feed, for 6 months. In the control group, the animals received feed without Bioverm®. Each group remained throughout the experiment in a 1.2-ha paddock. Monthly counts of eggs per gram (EPG) of feces, fecal cultures, packed cell volume (PCV), weight measurements, and collection of leaf mass from the pasture were performed. There was greater reduction in EPG, greater weight gain, and less infestation by infective larvae in the paddock of the Bioverm® group, compared with the control group (p < 0.05). There was no significant difference (p ≥ 0.05) in the mean PCV percentage between the Bioverm® and control groups. In coprocultures, Haemonchus sp. was the most prevalent helminth. Bioverm® (D. flagrans) was efficient for biological control of sheep gastrointestinal nematodes in the semiarid region of Brazil.


Assuntos
Nematoides , Doenças dos Ovinos , Animais , Ascomicetos , Brasil/epidemiologia , Fezes , Feminino , Larva , Óvulo , Contagem de Ovos de Parasitas/veterinária , Controle Biológico de Vetores , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/prevenção & controle
8.
J Helminthol ; 96: e33, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35514266

RESUMO

We report the first mermithid nematode found to be parasitic in a marine tanaidacean crustacean. Ten host tanaidaceans were collected from a depth of 52 m in Otsuchi Bay, Iwate, Japan, north-western Pacific, and identified as a species in the tanaidid genus Zeuxo Templeton, 1840. Nematodes occurred in the host's body cavity; in one case, at least two individuals inhabited a single host. We provide a brief description and illustrations of the morphology of the nematode. In a phylogenetic reconstruction based on the 18S ribosomal RNA gene, the nematode nested in a clade otherwise containing mermithids from terrestrial or freshwater hosts, showing an expansion in host utilization in Mermithidae Braun, 1883 from terrestrial/freshwater hosts to a marine organism.


Assuntos
Helmintos , Mermithoidea , Nematoides , Animais , Organismos Aquáticos , Água Doce , Humanos , Mermithoidea/anatomia & histologia , Mermithoidea/genética , Filogenia
9.
Front Immunol ; 13: 878783, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35515005

RESUMO

Nematodes and bacteria are prevalent in soil ecosystems, and some have evolved symbiotic relationships. In some cases, symbionts carry out highly specialized functions: a prime example being entomopathogenic nematodes (EPNs), which vector bacteria (Xenorhabdus or Photorhabdus) into insect hosts, killing them to provide a food source for the nematodes. It is thought that the commercially available malacopathogenic (kills slugs and snails) biocontrol nematode Phasmarhabditis hermaphrodita vectors a bacterium (Moraxella osloensis) into slugs to kill them. To investigate this further we used a metagenomic approach to profile the bacteria present in the commercial strain of P. hermaphrodita, a wild strain of P. hermaphrodita and two other Phasmarhabditis species (P. californica and P. neopapillosa), after they had killed their slug host (Deroceras invadens). We show that these nematodes do not exclusively associate with one bacterium but a range of species, with members of the phyla Pseudomonadota, Bacillota, Actinobacteriota and Bacteroidota the most prevalent. The commercial strain of P. hermaphrodita had the least diverse bacterial community. Furthermore, we found that the bacterium P. hermaphrodita has been cultured on for 25 years is not the expected species M. osloensis but is Psychrobacter spp. and the only strain of the Phasmarhabditis species to associate with Psychrobacter spp. was the commercial strain of P. hermaphrodita. In summary, we found no evidence to show that P. hermaphrodita rely exclusively on one bacterium to cause host mortality but found variable and diverse bacterial communities associated with these nematodes in their slug hosts.


Assuntos
Microbiota , Nematoides , Rhabditoidea , Animais , Rhabditoidea/microbiologia , Caramujos , Solo
10.
J Parasitol ; 108(2): 209-216, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35435986

RESUMO

The genus Eustrongylides includes zoonotic nematodes that infect fish species and fish-eating birds of freshwater ecosystems. This study aimed to evaluate the occurrence of Eustrongylides in the paratenic host Perca fluviatilis (European perch) and in the definitive host, Phalacrocorax carbo sinensis (great cormorant), in Lake Annone, a shallow eutrophic lake located in the pre-mountainous area of the Alps in northwest Italy where wintering cormorants coexist with new breeding colonies. A total of 114 European perch and 48 cormorants were examined for the occurrence of Eustrongylides. All parasites collected were identified with microscopic examination and molecular analysis. Overall, 11 specimens of European perch (9.6%) and 13 individuals of cormorants (27%) harbored nematodes identified as fourth-stage larvae and adults of Eustrongylides excisus. The observed prevalence of Eustrongylides spp. appears to be intermediate between the higher values in cormorant breeding areas in northern Europe and the lower prevalence observed in their wintering sites in southernmost Europe. Considering the eutrophication status of freshwater ecosystems and the increasing population of the cormorants, Eustrongylides has an increasing potential range of dispersion in Europe, including Italy; thus an extensive surveillance should be carried out, especially given the zoonotic potential of this nematode.


Assuntos
Dioctophymatoidea , Helmintos , Nematoides , Percas , Animais , Aves/parasitologia , Ecossistema , Lagos , Percas/parasitologia
11.
J Parasitol ; 108(2): 199-208, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35435987

RESUMO

Parasitic nematodes infect a variety of organisms including insects and vertebrates. To survive, they evade host immune responses to cause morbidity and mortality. Despite the vast clinical knowledge regarding nematode infections and their biological makeup, molecular understanding of the interactions between host and parasite remains poorly understood. The utilization of model systems has thus been employed to help elucidate the molecular interactions of the host immune response during parasitic nematode infection. Using model systems, it has been well established that parasitic nematodes evade host immunity by releasing excretory/secretory proteins (ESPs), which are involved in immunomodulation. Model systems have enabled researchers to characterize further the underlying mechanisms ESPs use to facilitate evasion and modulation of the host immune response. This review assessed notable ESPs from parasitic nematodes that infect vertebrates or insects and have been studied in mechanistic detail. Being able to characterize how ESPs affect the immune systems of hosts on a molecular level increases our understanding of host-parasite interactions and could lead to the identification of novel therapeutic targets and important molecular pathways.


Assuntos
Nematoides , Infecções por Nematoides , Parasitos , Animais , Interações Hospedeiro-Parasita/fisiologia , Imunidade , Imunomodulação , Infecções por Nematoides/parasitologia
12.
Molecules ; 27(7)2022 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-35408557

RESUMO

The treatment of parasitic infections requires the application of chemotherapy. In view of increasing resistance to currently in-use drugs, there is a constant need to search for new compounds with anthelmintic activity. A series of 16 cinnamylidene derivatives of rhodanine, including newly synthesized methoxy derivatives (1-11) and previously obtained chloro, nitro, and diethylamine derivatives (12-16), was investigated towards anthelmintic activity. Compounds (1-16) were evaluated against free-living nematodes of the genus Rhabditis sp. In the tested group of rhodanine derivatives, only compound 2 shows very high biological activity (LC50 = 0.93 µg/µL), which is higher than the reference drug albendazole (LC50 = 19.24 µg/µL). Crystal structures of two compounds, active 2 and inactive 4, were determined by the X-ray diffraction method to compare molecular geometry and search for differences responsible for observed biological activity/inactivity. Molecular modelling and selected physicochemical properties prediction were performed to assess the potential mechanism of action and applied in the search for an explanation as to why amongst all similar compounds only one is active. We can conclude that the tested compound 2 can be further investigated as a potential anthelmintic drug.


Assuntos
Anti-Helmínticos , Nematoides , Rhabditoidea , Rodanina , Animais , Anti-Helmínticos/química , Anti-Helmínticos/farmacologia , Modelos Moleculares , Rodanina/química
13.
Molecules ; 27(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408596

RESUMO

Coumarin derivatives have been reported as strong antifungal agents against various phytopathogenic fungi. In this study, inhibitory effects of nine coumarinyl Schiff bases were evaluated against the plant pathogenic fungi (Fusarium oxysporum f. sp. lycopersici, Fusarium culmorum, Macrophomina phaseolina and Sclerotinia sclerotiourum). The compounds were demonstrated to be efficient antifungal agents against Macrophomina phaseolina. The results of molecular docking on the six enzymes related to the antifungal activity suggested that the tested compounds act against plant pathogenic fungi, inhibiting plant cell-wall-degrading enzymes such as endoglucanase I and pectinase. Neither compound exhibited inhibitory effects against two beneficial bacteria (Bacillus mycoides and Bradyrhizobium japonicum) and two entomopathogenic nematodes. However, compound 9 was lethal (46.25%) for nematode Heterorhabditis bacteriophora and showed an inhibitory effect against acetylcholinesterase (AChE) (31.45%), confirming the relationship between these two activities. Calculated toxicity and the pesticide-likeness study showed that compound 9 was the least lipophilic compound with the highest aquatic toxicity. A molecular docking study showed that compounds 9 and 8 bind directly to the active site of AChE. Coumarinyl Schiff bases are promising active components of plant protection products, safe for the environment, human health, and nontarget organisms.


Assuntos
Ascomicetos , Fusarium , Nematoides , Acetilcolinesterase/farmacologia , Animais , Antifúngicos/química , Antifúngicos/farmacologia , Bactérias , Fungos , Humanos , Simulação de Acoplamento Molecular , Doenças das Plantas/microbiologia , Plantas , Bases de Schiff/farmacologia , Solo
14.
Curr Biol ; 32(8): R367-R370, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35472425

RESUMO

The nematode Pristionchus pacificus occasionally encounters other nematode species that compete for similar resources. A new study shows that P. pacificus perform an aggressive patrolling and biting behavior to expel adult Caenorhabditis elegans nematodes from food patches.


Assuntos
Nematoides , Animais , Caenorhabditis elegans
15.
Parasit Vectors ; 15(1): 116, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35365181

RESUMO

BACKGROUND: The genus Cissophyllus (Cosmocercoidea: Kathlaniidae) is a rare group of nematodes parasitic in turtles and lizards. To date, only four species have been reported in Asia and North America. However, most of them are inadequately described. The species Cissophyllus leytensis has never been reported since it was originally described by Tubangui and Villaamil in 1933 from the Philippine sailfin lizard Hydrosaurus pustulatus (Eschscholtz, 1829) (Reptilia: Squamata). Furthermore, the systematic status of Cissophyllus/Cissophyllinae in the family Kathlaniidae of the superfamily Cosmocercoidea remains under debate. METHODS: The detailed morphology of C. leytensis was studied using light microscopy (LM) and, for the first time, scanning electron microscopy (SEM), based on newly collected specimens from the type host H. pustulatus. Six different genetic markers, including nuclear sequences [small ribosomal subunit (18S), internal transcribed spacer (ITS) and large ribosomal subunit (28S)], plus mitochondrial genes [cytochrome c oxidase subunit 1 (cox1), cytochrome c oxidase subunit 2 (cox2) and 12S small subunit ribosomal RNA gene] of C. leytensis were sequenced. Additionally, in order to test the validity of the subfamily Cissophyllinae and clarify the phylogenetic relationships of Cissophyllus and the other genera in the family Kathlaniidae, phylogenetic analyses based on 18S + 28S and ITS sequence data were performed using maximum likelihood (ML) and Bayesian inference (BI) analyses, respectively. RESULTS: Our observations using LM and SEM revealed some previously unreported morphological features, necessitating the redescription of this poorly known species. The presence of remarkable morphological variation in the isthmus and the position of excretory pore among different individuals was found. Molecular analysis showed no intraspecific nucleotide divergence detected in the 18S, ITS, 28S, cox2 and 12S regions among different individuals of C. leytensis, but a low level of intraspecific genetic variation was found in the cox1 (0.52%). Our phylogenetic results showed the representatives of the Cosmocercoidea divided into four large clades (Cosmocerca + Aplectana + Cosmocercoides representing the family Cosmocercidae, Cruzia representing the subfamily Cruzinae of Kathlaniidae, Falcaustra + Cissophyllus + Megalobatrachonema representing the subfamily Kathlaniinae of Kathlaniidae, and Orientatractis + Rondonia representing the family Atractidae). The genus Cissophyllus clustered together with the genus Megalobatrachonema in both the ML and BI trees using ITS sequence data, but displayed a sister relationship to the genus Falcaustra in the ML tree and to the genera Falcaustra + Megalobatrachonema in the BI tree using 18S + 28S sequence data. CONCLUSIONS: Molecular phylogenetic results further confirmed that the family Kathlaniidae is not a monophyletic group. The subfamily Cruziinae should be moved from the hitherto-defined family Kathlaniidae and elevated as a separate family Cruziidae. The present phylogenetic results also negated the validity of the subfamily Cissophyllinae and supported the genus Cissophyllus assigned in the subfamily Kathlaniinae. Molecular analysis indicated that the morphological variation in the isthmus and position of excretory pore among different individuals should be considered as intraspecific variation. Moreover, some characters important for the specific diagnosis of C. leytensis are reported for the first time: the number of acuminate denticles (lamellae) on each lip, the chitinized pharynx with three flabellate pharyngeal plates, the presence of single medioventral precloacal papilla and the detailed morphology of caudal papillae. The present study is only the second record of C. leytensis.


Assuntos
Ascaridídios , Lagartos , Nematoides , Parasitos , Animais , Ascaridídios/anatomia & histologia , Teorema de Bayes , Filipinas , Filogenia
16.
J Vis Exp ; (181)2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35435903

RESUMO

Entomopathogenic nematodes in the genera Heterorhabditis and Steinernema are obligate parasites of insects that live in the soil. The main characteristic of their life cycle is the mutualistic association with the bacteria Photorhabdus and Xenorhabdus, respectively. The nematode parasites are able to locate and enter suitable insect hosts, subvert the insect immune response, and multiply efficiently to produce the next generation that will actively hunt new insect prey to infect. Due to the properties of their life cycle, entomopathogenic nematodes are popular biological control agents, which are used in combination with insecticides to control destructive agricultural insect pests. Simultaneously, these parasitic nematodes represent a research tool to analyze nematode pathogenicity and host anti-nematode responses. This research is aided by the recent development of genetic techniques and transcriptomic approaches for understanding the role of nematode secreted molecules during infection. Here, a detailed protocol on maintaining entomopathogenic nematodes and using a gene knockdown procedure is provided. These methodologies further promote the functional characterization of entomopathogenic nematode infection factors.


Assuntos
Nematoides , Photorhabdus , Xenorhabdus , Animais , Insetos/genética , Nematoides/genética , Nematoides/microbiologia , Photorhabdus/genética , Simbiose/genética , Xenorhabdus/genética
17.
Trop Anim Health Prod ; 54(3): 171, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35471467

RESUMO

Gastrointestinal nematodes cause serious economic losses in sheep production systems. To determine the prevalence and risk factors associated with these parasites, a study was conducted on 595 sheep in Córdoba, Colombia. Prevalence and parasite burden were determined using the McMaster technique. Larvae were cultured from feces to identify the nematode genera. For the analysis of associated factors and parasite burden, data means, medians, and confidence intervals were compared. A georeferenced data analysis was performed and an epidemiological map was constructed. An overall prevalence of 88.2% was found, with the highest prevalence and parasite burden for Strongylida (83.2%) and Strongyloides (41%) nematodes. The mean parasite burden was 1255 eggs per gram. The gastrointestinal nematode genera identified were Trichostrongylus, Strongyloides, Haemonchus, Oesophagostomum, Bunostomum, and Cooperia. In general, a significant association was found between parasite burden and dewormed animals, anthelmintic used, date of last deworming, and breeds. The FAMACHA® method and body condition showed a significant association with the Strongylida parasite burden. Clusters with higher intensity of gastrointestinal nematode burden and high prevalence were observed in the regions of Bajo Sinú, Sinú Medio, and San Jorge.


Assuntos
Doenças Transmissíveis , Gastroenteropatias , Nematoides , Infecções por Nematoides , Parasitos , Doenças dos Ovinos , Estrongilídios , Animais , Colômbia/epidemiologia , Doenças Transmissíveis/veterinária , Gastroenteropatias/veterinária , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Infecções por Nematoides/veterinária , Óvulo , Contagem de Ovos de Parasitas/veterinária , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia
18.
PLoS Pathog ; 18(4): e1010424, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35446920

RESUMO

Fatty acid-and retinol-binding proteins (FARs) belong to a unique family of excreted/secreted proteins (ESPs) found exclusively in nematodes. Much of our understanding of these proteins, however, is limited to their in vitro binding characteristics toward various fatty acids and retinol and has provided little insight into their in vivo functions or mechanisms. Recent research, however, has shown that FARs elicit an immunomodulatory role in plant and animal model systems, likely by sequestering lipids involved in immune signaling. This alludes to the intricate relationship between parasitic nematode effectors and their hosts.


Assuntos
Nematoides , Proteínas de Ligação ao Retinol , Animais , Ácidos Graxos/metabolismo , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Nematoides/genética , Nematoides/metabolismo , Proteínas de Ligação ao Retinol/genética , Proteínas de Ligação ao Retinol/metabolismo , Vitamina A/metabolismo
19.
Ecotoxicol Environ Saf ; 237: 113559, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35483151

RESUMO

Bacterivorous nematodes are abundant in petroleum-contaminated soils. However, the ecological functions of bacterivorous nematodes and their impacts together with the addition of organic materials on the activity and diversity of microorganisms in petroleum-contaminated soils remain unknown. To assess such effects, six treatments were established in this study, including uncontaminated nematodes-free soil (Control), petroleum-contaminated soil (PC), petroleum-contaminated soil + 5 nematodes per gram dry soil (PCN), and petroleum-contaminated soil + 5 nematodes per gram dry soil + 1% wheat straw (PCNW), or + 1% rapeseed cake (PCNR), or + 1% biochar (PCNB). Results showed that the enzyme activities in the six treatments generally increased firstly and then decreased during the incubation period. Compared with Control, the invertase activity in PCNW, PCNR, and PCNB increased by 80.6%, 313.5%, and 12.4%, respectively, whereas the urease activity in PC, PCN, PCNW, PCNR, and PCNW increased by 1.2%, 25.5%, 124.3%, 105.3%, and 25.5%, respectively. Petroleum pollution, inoculation of bacterivorous nematodes, and the addition of organic materials all significantly boosted the concentrations of phospholipid fatty acids (PLFAs) of soil bacteria, actinobacteria, and total microorganisms, and increased the concentrations of both G+ and G- bacteria PLFAs and the ratio of G-/G+. The concentration of fungi PLFAs and the ratio of fungi to bacteria were significantly higher in PCNW and PCNR than those in other treatments. Overall, adding bacterivorous nematodes and organic materials to the petroleum-contaminated soil significantly improved soil microbial activity and community structure, suggesting that bacterivorous nematodes could be used for the bioremediation in petroleum contaminated soils.


Assuntos
Nematoides , Petróleo , Poluentes do Solo , Animais , Bactérias , Biodegradação Ambiental , Petróleo/toxicidade , Carbonitrila de Pregnenolona , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise
20.
Vet Parasitol Reg Stud Reports ; 30: 100713, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35431071

RESUMO

A questionnaire was sent to sheep owners in Sweden to get information about anthelmintic drug use. The survey also investigated how respondents experienced problems with gastrointestinal nematode infections (GIN) focusing on Haemonchus contortus. The response rate was 31% and included both conventional and organic farms. The use of anthelmintics was low (45%), among which a majority (76%) drenched ewes on a single occasion, mostly with ivermectin (59%) followed by albendazole (19%). Other drugs were used rarely, however, unawareness of GIN risk was high (19%), especially among respondents with few animals. Anthelmintic dose calculations were done after visual appraisal by 63% and 22% calibrated the equipment before drug delivery, which is worrying since underdosing is a risk factor for the development of anthelmintic resistance. Like with anthelmintics, the perceived risk for GIN increased with herd size both by conventional and organic farmers. Faecal examination for the presence of GIN was done by 65% of the respondents and, among their sheep, H. contortus was or had been diagnosed in 41% of the herds. Irrespective of new stock had been imported from other countries or not, common problems were reported by 5% and 7% of the organic and conventional producers, respectively. Land use and grazing management strategies differed more in relation to herd size than by production form, with a majority (47%) having their sheep grazed in several paddocks, or at least the lambs were moved when separated from the ewes at weaning (25%). In contrast set stocked grazing was mainly reported on smaller farms. Co-grazing with cattle and horses were also frequently reported irrespective of production form, but with cattle to a somewhat greater degree on larger organic farms. Wild cervids, especially roe deer, were frequently observed on sheep pastures (87%). The veterinary involvement was higher on organic (65%) than on conventional farms (53%), and only 5% considered advice unimportant. Still, some conventional and organic producers treated sheeps routinely without a prior diagnosis, against the national regulations. 46% of the respondents drenched new and replacement stock. In conclusion, although some differences were observed between conventional and organic producers, the divergences were mainly due to herd size categories. Furthermore, despite a high veterinary involvement, we identified factors which can contribute to anthelmintic use, such as poor quarantine procedures, and deworming routines that can contribute to anthelmintic resistance in H. contortus.


Assuntos
Anti-Helmínticos , Doenças dos Bovinos , Cervos , Gastroenteropatias , Doenças dos Cavalos , Enteropatias Parasitárias , Nematoides , Infecções por Nematoides , Parasitos , Doenças dos Ovinos , Animais , Anti-Helmínticos/uso terapêutico , Bovinos , Doenças dos Bovinos/parasitologia , Fazendeiros , Feminino , Gastroenteropatias/parasitologia , Gastroenteropatias/veterinária , Doenças dos Cavalos/tratamento farmacológico , Cavalos , Humanos , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/prevenção & controle , Enteropatias Parasitárias/veterinária , Infecções por Nematoides/veterinária , Percepção , Ovinos , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/prevenção & controle , Suécia/epidemiologia
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