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1.
PeerJ ; 12: e17976, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39364365

RESUMO

New species of the genera Spirobolbolaimus and Ixonema (Nematoda: Microlaimidae) have been found in sediment samples collected in the South Atlantic, along the Continental Shelf break off Northeastern Brazil. Different to other Spirobolbolaimus species, S. pernambucanus sp. nov. possesses six outer labial setae and four cephalic setae with approximately the same length. Ixonema gracieleae sp. nov. differs from other species of Ixonema in having somatic setae on peduncles. This is the first time that new species of these taxa have been described for the Brazilian coast. An amendment of the diagnosis and a dichotomous key are proposed for both genera.


Assuntos
Nematoides , Animais , Brasil , Oceano Atlântico , Nematoides/classificação , Nematoides/isolamento & purificação , Masculino , Sedimentos Geológicos/parasitologia
2.
Vet Parasitol Reg Stud Reports ; 54: 101096, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39237237

RESUMO

The giant African land snail Achatina fulica is known to be the intermediate host of a number of nematode species that are prejudicial to human and veterinary health, being also an agricultural and urban pest. The present study investigated the presence of nematodes in A. fulica and other terrestrial mollusks in 24 municipalities of Sergipe State, northeastern of Brazil, in the dry and rainy seasons. In 2019 and 2020, the specimens were collected in standard 20 m × 10 m plots (10 min/01 collector), while in 2021, they were collected by convenience sampling. The nematode species were identified based on sequencing of the mitochondrial Cytochrome C Oxidase Subunit I (COI) gene and the ribosomal nuclear Internal Transcribed Spacer (ITS 2). Specimens of A. fulica infected with Angiostrongylus cantonensis, a nematode that causes eosinophilic meningitis (EM) in humans and animals, were collected in four municipalities. Two nematodes of veterinary importance were also identified, Aelurostrongylus abstrusus and Cruzia tentaculata in seven municipalities. This is the first record of Cruzia tentaculata in Sergipe. Free-living nematodes were also found in 18 municipalities. One of these species - Caenorhabditis briggsae - was identified in the municipality of Itabaiana. Specimens of other mollusks species were also collected. Only one of these mollusks, C. fasciata from Japaratuba, was found infected with free-living nematodes. A. fulica showed greater positivity for nematodes in the dry season, especially in the regions of Lower São Francisco River, Greater Aracaju and South Central Sergipe. The probability of infection increased when mollusks were larger and more recurrent in plots. Given that A. cantonensis is the etiological agent of EM and was found associated to A. fulica in four municipalities, it will be important to implement programs of continuous monitoring of the mollusk's fauna, combined with educational programs that provide information necessary to control A. fulica.


Assuntos
Caramujos , Animais , Brasil/epidemiologia , Caramujos/parasitologia , Nematoides/isolamento & purificação , Nematoides/classificação , Espécies Introduzidas , Humanos , Estações do Ano
3.
Rev Bras Parasitol Vet ; 33(3): e011224, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39292069

RESUMO

Populations of freshwater species have been declining rapidly and species are becoming extinct. Thus, understanding freshwater species distribution, trends and patterns is required. The Munim River basin is situated in a region with a phytogeographic interface between the Amazon and Cerrado biomes. Although the Munim basin ichthyofauna is currently relatively well-known, data on its helminth fauna is scarce. The present study aimed to characterize the nematofauna of Bryconops cf. affinis (Günther) and Saxatilia brasiliensis (Bloch) from two different localities in the middle section of the Munim River, and thus to contribute to the knowledge of biodiversity in this region. Specimens of Bryconops cf. affinis were parasitized with the nematodes Procamallanus (Spirocamallanus) krameri (Petter, 1974) and "Porrocaecum-like" species (larvae) in both localities. Saxatilia brasiliensis presented the nematodes P. (S.) krameri, Pseudoproleptus sp. (larvae), Cucullanus sp. and Procamallanus sp. (larvae). Procamallanus (S.) krameri was found parasitizing S. brasiliensis only from the Feio stream. Morphometric data and parasitological parameters are given. The present study provides the first record of nematodes for B. cf. affinis and for S. brasiliensis contributing to the knowledge of the helminth fauna of freshwater fishes from locations that have not yet been studied, such as the Munim River basin.


Assuntos
Caraciformes , Rios , Animais , Brasil , Caraciformes/parasitologia , Nematoides/classificação , Nematoides/isolamento & purificação , Ciclídeos/parasitologia
4.
Rev Bras Parasitol Vet ; 33(3): e010524, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39140497

RESUMO

This review outlines the current state of anthelmintic resistance (AHR) of gastrointestinal nematodes (GINs) among cattle in Argentina and Brazil, emphasizing the economic repercussions, animal health and welfare. The analysis explores factors associated with AHR and proposes a potential solution: the use of drug combinations. Both countries are grappling with a severe AHR scenario in cattle, having progressed through incipient, established, and advanced phases, leading to extreme cases of animal mortality due to ineffective control strategies. Genera such as Cooperia and Haemonchus have the highest reports of resistance, with Oesophagostomum radiatum also posing significant problems. While oral benzimidazoles and levamisole remain effective in most herds, moxidectin is entering an advanced resistance phase, and avermectins are increasingly deemed ineffective. The review explores the impact ofclimate, mixed grazing, animal movement and other husbandry practices, and the relationship between ectoparasite control and the emergence of resistant helminths. Notably, the discussion includes the strategic use of drug combinations as a valuable approach to address resistant GINs control in livestock, highlighting its significant potential to mitigate the challenges posed by AHR in the cattle industry of these countries.


Assuntos
Anti-Helmínticos , Doenças dos Bovinos , Resistência a Medicamentos , Nematoides , Infecções por Nematoides , Animais , Bovinos/parasitologia , Brasil , Argentina , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Infecções por Nematoides/veterinária , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Anti-Helmínticos/uso terapêutico , Nematoides/efeitos dos fármacos
5.
J Helminthol ; 98: e48, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39189368

RESUMO

This article presents a checklist of metazoan parasites of snakes from Argentina, along with a comprehensive review of the relevant literature published between 1922 and June 2023, covering various aspects of interest. We compiled 34 species of metazoan endoparasites from 28 studies. The subclass Digenea showed the highest number of species (n = 22 species), followed by the phylum Nematoda (n = 8 species), and the subclass Pentastomida (n = 3 species and 1 taxa inquirenda). Dipsadidae was the family of snakes with the most species examined for metazoan endoparasites (n = 20 species). In contrast, Viperidae had the largest number of specimens surveyed (n = 343). Of 23 provinces, 15 (65.2%) presented at least one report of metazoan endoparasites in snakes. The northeastern provinces showed the highest richness of metazoan endoparasites and host diversity. Many articles focused on taxonomy, but studies on parasite ecology were not found. Although taxonomic accuracy was high in most reports, some records were correctly deposited in zoological collections or geo-referenced. This is the first attempt to include all groups of metazoan endoparasites of snakes from Argentina in a single checklist in the last century.


Assuntos
Serpentes , Animais , Serpentes/parasitologia , Argentina , Lista de Checagem , Parasitos/classificação , Parasitos/isolamento & purificação , Nematoides/classificação , Nematoides/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Doenças Parasitárias em Animais/epidemiologia , Biodiversidade
6.
Vet Parasitol Reg Stud Reports ; 53: 101066, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39025540

RESUMO

Cuniculus paca, commonly known as the paca, is a rodent of the Cuniculidae family that is widely distributed throughout the Americas, including all Brazilian territories, and is abundant in the Amazon region. It is one of the most hunted species and faces significant predation in the extreme western Amazon region of Brazil because it constitutes a staple in the diet of local communities, for subsistence and commercial purposes. Understanding the helminthic fauna of these animals is of paramount importance, given that some nematodes have zoonotic potential and may pose risks to consumer health. This study aimed to contribute to the records of the nemtodes of this highly consumed species in the Amazon region, highlighting the occurrence of gastrointestinal parasites in free-living pacas intended for human subsistence consumption. The study was conducted in the Paranã da Floresta community, located in the municipality of Guajará, Amazonas from 2022 to 2023. The community members hunted this rodent for consumption and voluntarily provided the viscera for analysis. Nematodes were extracted from each organ. The organs were opened, and the contents were processed using a sieve (0.15 mm) and subsequently evaluated separately. In total, 10,157 nematodes were found in the 14 pacas. Based on morphological analyses, the nematodes were identified as Heligmostrongylus sedecimradiatus (n = 10,068), Trichuris sp. (n = 85), and Physaloptera sp. (n = 4). This study provides insights into the nematodes diversity of free-living pacas in the extreme Western Amazon region, emphasizing the importance of sanitary surveillance and public awareness of the risks associated with bushmeat consumption.


Assuntos
Nematoides , Infecções por Nematoides , Animais , Brasil/epidemiologia , Nematoides/isolamento & purificação , Nematoides/classificação , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Infecções por Nematoides/epidemiologia , Cuniculidae/parasitologia , Masculino , Feminino , Doenças dos Roedores/parasitologia , Doenças dos Roedores/epidemiologia , Humanos
7.
Sci Rep ; 14(1): 15456, 2024 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965317

RESUMO

Medicinal plant microbiomes undergo selection due to secondary metabolite presence. Resident endophytic/epiphytic microorganisms directly influence plant's bioactive compound synthesis. Hypothesizing low microbial diversity in Serjania erecta leaves, we assessed leaf colonization by epiphytic and endophytic fungi. Given its traditional medicinal importance, we estimated diversity in the endophytic fungal microbiome. Analyses included scanning electron microscopy (SEM), isolation of cultivable species, and metagenomics. Epiphytic fungi interacted with S. erecta leaf tissues, horizontally transmitted via stomata/trichome bases, expressing traits for nematode trapping. Cultivable endophytic fungi, known for phytopathogenic habits, didn't induce dysbiosis symptoms. This study confirms low leaf microbiome diversity in S. erecta, with a tendency towards more fungal species, likely due to antibacterial secondary metabolite selection. The classification of Halicephalobus sp. sequence corroborated the presence of nematode eggs on the epidermal surface of S. erecta by SEM. In addition, we confirmed the presence of methanogenic archaea and a considerable number of methanotrophs of the genus Methylobacterium. The metagenomic study of endophytic fungi highlighted plant growth-promoting yeasts, mainly Malassezia, Leucosporidium, Meyerozyma, and Hannaella. Studying endophytic fungi and S. erecta microbiomes can elucidate their impact on beneficial bioactive compound production, on the other hand, it is possible that the bioactive compounds produced by this plant can recruit specific microorganisms, impacting the biological system.


Assuntos
Fungos , Microbiota , Nematoides , Folhas de Planta , Folhas de Planta/microbiologia , Folhas de Planta/parasitologia , Animais , Nematoides/microbiologia , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Endófitos/genética , Endófitos/isolamento & purificação , Leveduras/classificação , Leveduras/isolamento & purificação , Leveduras/genética , Metagenômica/métodos , Biodiversidade
8.
An Acad Bras Cienc ; 96(3): e20230339, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38896740

RESUMO

Cucullanus lithodorasi n. sp. (Nematoda: Cucullanidae), collected from the intestine of Lithodoras dorsalis (Siluriformes) and waters of the north coast of Brazil is described based on light and scanning electron microscopic observations. The new species differs from its congeners in the number and arrangement of cloacal papillae: five precloacal pairs and five postcloacal pairs and presence of unpaired ventral papillae located slightly anterior to the cloaca. This is the third nominal species of the genus infecting fishes from brackish water from Brazil.


Assuntos
Peixes-Gato , Doenças dos Peixes , Microscopia Eletrônica de Varredura , Animais , Brasil , Peixes-Gato/parasitologia , Doenças dos Peixes/parasitologia , Masculino , Feminino , Nematoides/classificação , Nematoides/anatomia & histologia , Nematoides/ultraestrutura , Nematoides/isolamento & purificação
9.
Rev Bras Parasitol Vet ; 33(2): e019723, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38896756

RESUMO

Ctenocephalides felis felis is a relevant and widely distributed ectoparasite that acts as a vector of disease-causing pathogens. Moreover, it is responsible for economic losses due the use of harmful chemicals to the environment and that favor the emergence of insecticide-resistant populations. Research on entomopathogenic nematodes may open up an alternative route to the insect chemical control. The present study aimed to evaluate the killing efficacy of Heterorhabditis bacteriophora (HP88) against C. felis larvae in 400 µL, 600 µL and 1000 µL of suspension containing 120, 160 and 200 infective juveniles/larva and 600 µL of suspension containing the same concentrations of Heterorhabditis indica (LPP30), divided into two groups (absence and presence of diet) and a control group with three replications containing only distilled water. In the bioassay with H. bacteriophora, the groups in 600 µL of suspension showed higher mortality rates than those in the other tested volumes, which were above 80% at all concentrations. On the other hand, H. indica achieved mortality rates above 70% at all concentrations used. Results indicate that flea larvae are susceptible to in vitro infection by H. bacteriophora and H. indica.


Assuntos
Ctenocephalides , Larva , Animais , Larva/crescimento & desenvolvimento , Ctenocephalides/crescimento & desenvolvimento , Controle Biológico de Vetores , Nematoides
10.
Parasitol Int ; 102: 102914, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38908472

RESUMO

Knowledge of parasite-host interactions is essential for understanding factors associated with the ecology and evolution of both groups. Some aspects, such as host size and phylogeny, as well as parasite specificity, are significant predictors that help unveil the parasite-host relationship. Thus, the goals of this study were: (1) to describe parasite diversity in regions of the Atlantic Forest; (2) to analyze which host characteristics can influence parasite richness of anuran's parasite component community; and (3) to investigate if the prevalence of parasite infection is related to specificity metrics (ecological and phylogenetic), number of infected hosts and parasite's abundance. We identified 49 parasite taxa, classified into three phyla: Nematoda, Acanthocephala, and Platyhelminthes. Supporting the existing literature, our findings corroborate the positive relationship between host size and parasite richness, further emphasizing the significance of this predictor. Parasite prevalence in the host community is related to the number of infected host species and parasite abundance, but not to phylogenetic and ecological specificity indices. This shows that parasite prevalence is strongly associated with infection opportunity, host sampling effort, and high parasite abundance.


Assuntos
Anuros , Biodiversidade , Florestas , Interações Hospedeiro-Parasita , Nematoides , Filogenia , Animais , Anuros/parasitologia , Nematoides/classificação , Brasil/epidemiologia , Acantocéfalos/classificação , Acantocéfalos/fisiologia , Acantocéfalos/isolamento & purificação , Prevalência , Helmintos/classificação , Helmintos/isolamento & purificação , Helmintos/genética , Especificidade de Hospedeiro
11.
PLoS One ; 19(6): e0306390, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38935803

RESUMO

The economic impact of gastrointestinal (GI) nematode infections on livestock production is well documented worldwide. Increasing evidence supports the hypothesis that parasite colonization induces significant changes in the GI tract environment and, therefore, in the landscape where the microbiota and parasites occur. Understanding the interactions between bacterial and parasite populations in the digestive tract of livestock may be useful to design parasite control strategies based on microbiota modification. The aims of this work were to investigate the impact of the oxytetracycline-mediated manipulation of the gut microbial community on the composition of GI nematode populations in naturally infected sheep and to explore changes in the GI microbial communities after nematode population treatment with the anthelmintic compound monepantel. Extensive manipulation of the GI microbiota with a therapeutic dose of the long-acting oxytetracycline formulation did not induce significant changes in the GI nematode burden. The gut microbiota of treated animals returned to control levels 17 days after treatment, suggesting strong resilience of the sheep microbial community to antibiotic-mediated microbiota perturbation. A significant decrease of the bacterial Mycoplasmataceae family (Log2FC = -4, Padj = 0.001) and a marked increase of the Methanobacteriaceae family (Log2FC = 2.9, Padj = 0.018) were observed in the abomasum of sheep receiving the monepantel treatment. While a comprehensive evaluation of the interactions among GI mycoplasma, methanobacteria and nematode populations deserves further assessment, the bacteria-nematode population interactions should be included in future control programs in livestock production. Understanding how bacteria and parasites may influence each other in the GI tract environment may substantially contribute to the knowledge of the role of microbiota composition in nematode parasite establishment and the role of the parasites in the microbiota composition.


Assuntos
Microbioma Gastrointestinal , Trato Gastrointestinal , Nematoides , Infecções por Nematoides , Oxitetraciclina , Doenças dos Ovinos , Animais , Ovinos/parasitologia , Ovinos/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/tratamento farmacológico , Infecções por Nematoides/veterinária , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Infecções por Nematoides/microbiologia , Nematoides/microbiologia , Nematoides/efeitos dos fármacos , Nematoides/fisiologia , Oxitetraciclina/farmacologia , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/parasitologia , Aminoacetonitrila/análogos & derivados , Aminoacetonitrila/farmacologia , Bactérias/efeitos dos fármacos
12.
PeerJ ; 12: e17355, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38708361

RESUMO

Three new species of the Microlaimus genus (Nematoda: Microlaimidae) are described from sample sediments collected in the South Atlantic, along the Continental Shelf break of Northeastern Brazil. Microlaimus paraundulatus sp. n. possesses four setiform cephalic sensillae, a buccal cavity with three small teeth, arched and slender spicules and a wave-shaped gubernaculum. Microlaimus modestus sp. n. is characterized by four small cephalic sensillae, a buccal cavity with three teeth (one large dorsal tooth), cephalated spicules and a strongly arched gubernaculum in the distal region. Microlaimus nordestinus sp. n. is characterized by the following set of features: relatively long body, eight rows of hypodermal glands that extend longitudinally along the body and a funnel-shaped gubernaculum surrounding the spicules at the distal end. An amendment of the diagnosis is proposed for the genus.


Assuntos
Sedimentos Geológicos , Animais , Brasil , Oceano Atlântico , Sedimentos Geológicos/parasitologia , Masculino , Nematoides/classificação , Nematoides/anatomia & histologia , Nematoides/isolamento & purificação , Feminino
13.
J Helminthol ; 98: e39, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38726571

RESUMO

During nematode surveys of natural vegetation in forests of La Cima de Copey de Dota, San José, San José province, Costa Rica, a Xenocriconemella species closely resembling X. macrodora and related species was found. Integrative taxonomical approaches demonstrated that it is a new species described herein as X. costaricense sp. nov. The new species is parthenogenetic (only females have been detected) and characterised by a short body (276-404 µm); lip region with two annuli, not offset, not separated from body contour; first lip annulus partially covering the second lip annulus. Stylet thin, very long (113-133 µm) and flexible, occupying 30.5-47.8% of body length. Excretory pore located from one or two annuli anterior to one or two annuli posterior to level of stylet knobs, at 42 (37-45) µm from anterior end. Female genital tract monodelphic, prodelphic, outstretched, and occupying 35-45% of body length, with vagina slightly ventrally curved (14-18 µm long). Anus located 6-11 annuli from the tail terminus. Tail conoid and bluntly rounded terminus, the last 2-3 annuli oriented dorsally. Results of molecular characterisation and phylogenetic analyses of D2-D3 expansion segments of 28S rRNA, ITS, and partial 18S rRNA, as well as cytochrome oxidase c subunit 1 gene sequences further characterised the new species and clearly separated it from X. macrodora and other related species (X. iberica, X. paraiberica, and X. pradense).


Assuntos
Filogenia , Animais , Costa Rica , Feminino , Masculino , Nematoides/classificação , Nematoides/anatomia & histologia , Nematoides/genética , DNA Ribossômico/genética , RNA Ribossômico 28S/genética , DNA de Helmintos/genética , Florestas , Análise de Sequência de DNA
14.
Parasitol Res ; 123(5): 208, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38724709

RESUMO

In freshwater ecosystems, parasite infection patterns are influenced by factors including spatial-temporal variations, host diet, and habitat. Fish often change diets, affecting their parasite communities. This study focused on non-native host fish Geophagus sveni, aiming to characterize diet and endoparasitic helminth fauna patterns in the invaded area, investigating spatial and seasonal possible differences of endoparasite infections and correlating with host diet, in São José dos Dourados River and Tietê River areas. The host fish were collected in these areas during the dry and rainy season using gillnets. The endoparasites were collected and preserved in alcohol and identified using taxonomic methods, and stomach contents were examined for diet analysis. Parasitism descriptors were calculated and evaluated spatially and seasonally by ANOVA and the Kruskal-Wallis tests. PERMANOVA assessed G. sveni diet differences, and RDA correlated the endohelminth abundance with the host diet. Two endoparasites were recorded: metacercariae of Austrodiplostomum compactum (Trematoda) and larvae and adults of Raphidascaris (Sprentascaris) lanfrediae (Nematoda). Spatial differences were observed for the mean abundance and prevalence of R. (S.) lanfrediae and A. compactum prevalence. Seasonal variations of parasitic descriptors occurred for the nematode in the Tietê River area. The detritus and aquatic insects were the most consumed items by G. sveni. Detritus consumption positively correlates with nematode abundance. The findings indicate that factors such as artificial channels and rainfall, which can influence resource availability, may affect the fish's diet and potentially influence the structure of its endoparasite community. The study emphasizes the importance of understanding trophic chain-transmitted parasites and calls for further research in Neotropical environments.


Assuntos
Dieta , Doenças dos Peixes , Helmintíase Animal , Rios , Estações do Ano , Animais , Rios/parasitologia , Doenças dos Peixes/parasitologia , Doenças dos Peixes/epidemiologia , Helmintíase Animal/parasitologia , Helmintíase Animal/epidemiologia , Trematódeos/isolamento & purificação , Trematódeos/classificação , Brasil/epidemiologia , Nematoides/isolamento & purificação , Nematoides/classificação , Helmintos/isolamento & purificação , Helmintos/classificação , Conteúdo Gastrointestinal/parasitologia
15.
Parasitol Res ; 123(5): 207, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713234

RESUMO

Biomarkers are specific molecular, histological, or physiological characteristics of normal or pathogenic biological processes and are promising in the diagnosis of gastrointestinal nematodes (GINs). Although some biomarkers have been validated for infection by Ostertagia sp. in cattle raised in temperate regions, there is a lack of information for tropical regions. The aim of this project was to assess potential biomarkers and validate the most promising. In the first study, 36 bovines (Nelore breed) naturally infected by GINs were distributed into two groups: infected (not treated with anthelmintic) and treated (treated with fenbendazole on days 0, 7, 14, 21, 28, 42, and 56). The variables of interest were live weight, fecal egg count, hemogram, serum biochemical markers, phosphorus, gastrin, and pepsinogen. In the second step, pepsinogen was assessed in cattle of the Nelore breed distributed among three groups: infected (not treated with anthelmintic), MOX (treated with moxidectin), and IVM + BZD (treated with ivermectin + albendazole). In the first study, no difference between groups was found for weight, albumin, hematocrit (corpuscular volume [CV]), erythrocytes, or hemoglobin. Negative correlations were found between pepsinogen and both CV and albumin, and albumin was negatively correlated with the percentage of Haemonchus sp. in the fecal culture. Among the biomarkers, only pepsinogen differentiated treated and infected (beginning with the 28th day of the study). In the second study, a reduction in pepsinogen was found after anthelmintic treatment. Therefore, pepsinogen is a promising biomarker of worms in cattle naturally infected by the genera Haemonchus and Cooperia in tropical areas.


Assuntos
Biomarcadores , Doenças dos Bovinos , Fezes , Infecções por Nematoides , Clima Tropical , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/tratamento farmacológico , Biomarcadores/sangue , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Infecções por Nematoides/tratamento farmacológico , Fezes/parasitologia , Contagem de Ovos de Parasitas , Anti-Helmínticos/uso terapêutico , Nematoides/isolamento & purificação , Nematoides/classificação , Nematoides/efeitos dos fármacos , Gastroenteropatias/parasitologia , Gastroenteropatias/veterinária , Enteropatias Parasitárias/veterinária , Enteropatias Parasitárias/parasitologia , Fenbendazol/uso terapêutico
16.
Rev Alerg Mex ; 71(1): 60, 2024 Feb 01.
Artigo em Espanhol | MEDLINE | ID: mdl-38683078

RESUMO

OBJECTIVE: This study aimed to identify by in silico methods tropomyosin consensus B and T epitopes of shrimp species, house dust mites, insects, and nematodes associated with allergic diseases in tropical countries. METHODS: In silico analysis included tropomyosin from mites (Der p 10, Der f 10, Blo t 10), insects (Aed a 10, Per a 7, Bla g 7), shrimp (Lit v 1, Pen m 1, Pen a 1), and nematode (Asc l 3) all sequences were taken from the UniProt database. Linear IgE epitopes were predicted with AlgPred 2.0 and validated with BepiPred 3.0. MHC-II binding T cell epitopes were predicted using the IEDB server, which implements nine predictive methods (consensus method, combinatorial library, NN-align-2.3, NN- align-2.2, SMM-align, Sturniolo, NetMHCIIpan 3.1, and NetMHCIIpan 3.2) these predictions focused on 10 HLA-DR and 2 HLA-DQ alleles associated with allergic diseases. Subsequently, consensus B and T epitopes present in all species were identified. RESULTS: We identified 12 sequences that behaved as IgE-epitopes and B-cell epitopes, three of them: 160RKYDEVARKLAMVEA174, 192ELEEELRVVGNNLKSLEVSEEKAN215, 251KEVDRLEDELV261 were consensus in all species. Eleven peptides (T-epitopes) showed strong binding (percentile rank ≤ 2.0) to HLA-DRB1*0301, *0402, *0411, *0701, *1101, *1401, HLA-DQA1*03:01/DQB1*03:02, and HLA- DQA1*05:01/DQB1*02:01. Only two T-epitopes were consensus in all species: 167RKLAMVEADLERAEERAEt GEsKIVELEEELRV199, and 218EEeY KQQIKT LTaKLKEAEARAEFAERSV246. Subsequently, we identified 2 B and T epitope sequences and reached a consensus between species 167RKLAMVEA174 and 192ELEEELRV199. CONCLUSIONS: These data describe three sequences that may explain the IgE cross-reactivity between the analyzed species. In addition, the consensus B and T epitopes can be used for further in vitro investigations and may help to design multiple-epitope protein-based immunotherapy for tropomyosin-related allergic diseases.


OBJETIVO: Este estudio tuvo como objetivo identificar mediante métodos in silico epítopes B y T consenso de tropomiosina de especies de camarón, ácaros del polvo doméstico, insectos y nematodos asociados a enfermedades alérgicas en países tropicales. MÉTODOS: El análisis in silico incluyó tropomiosina de ácaros (Der p 10, Der f 10, Blo t 10), insectos (Aed a 10, Per a 7, Bla g 7), camarones (Lit v 1, Pen m 1, Pen a 1), y nematodo (Asc l 3). Todas las secuencias se tomaron de la base de datos UniProt. Los epítopes IgE lineales se predijeron con AlgPred 2.0 y se validaron con BepiPred 3.0. Los epítopes de células T de unión a MHC-II se predijeron utilizando el servidor IEDB, que implementa nueve métodos predictivos (método de consenso, biblioteca combinatoria, NN-align-2.3, NN-align-2.2, SMM-align, Sturniolo, NetMHCIIpan 3.1 y NetMHCIIpan 3.2). Estas predicciones se centraron en diez alelos HLA-DR y 2 HLA-DQ asociados con enfermedades alérgicas. Posteriormente, se identificaron epítopes consenso B y T presentes en todas las especies. RESULTADOS: Se identificaron 12 secuencias que se comportaron como epítopes de IgE y, también, como epítopes de células B. Tres de ellas: 160RKYDEVARKLAMVEA174, 192ELEEELRVVGNNLKSLEVSEEKAN213 y 251KEVDRLEDELV261, fueron consenso en todas las especies. Once péptidos mostraron una fuerte unión (rango percentil ≤ 2,0) a HLA-DRB1*0301, *0402, *0411, *0701, *1101, *1401 y a HLA HLA-DQA1*03:01/DQB1*03:02, o HLA-DQA1*05:01/DQB1*02:01. Solo se encontraron dos secuencias: 167RKLAMVEADLERAEERAEtGEsKIVELEEELRV199 con fuerte afinidad por HLA-DQA1*03:01/DQB1*03:02, y HLA-DQA1*05:01/DQB1*02:01. Se identificaron dos secuencias que son epítopos B y T, y son consenso entre especies: 167RKLAMVEA174 y 192ELEEELRV199. CONCLUSIONES: Estos datos describen tres secuencias que pueden explicar la reactividad cruzada de IgE entre las especies analizadas. Además, los epítopos B y T consenso se pueden usar para investigaciones in vitro adicionales, y pueden ayudar a diseñar inmunoterapia basada en proteínas de múltiepítopes para enfermedades alérgicas relacionadas con la tropomiosina.


Assuntos
Simulação por Computador , Reações Cruzadas , Epitopos de Linfócito B , Epitopos de Linfócito T , Hipersensibilidade , Tropomiosina , Animais , Sequência Consenso , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Insetos/imunologia , Penaeidae/imunologia , Pyroglyphidae/imunologia , Tropomiosina/imunologia , Tropomiosina/genética , Hipersensibilidade/imunologia , Ácaros/imunologia , Crustáceos/imunologia , Nematoides/imunologia
17.
Sci Total Environ ; 930: 172612, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38663602

RESUMO

Mangroves develop under environmental conditions and anthropogenic pressures whose impact on benthic meiofauna remains poorly understood. It is unclear how meiofauna communities are structured according to local sedimentary conditions. This study was designed to characterize the community structure of meiofauna and nematodes (dominant taxa) and the associated environmental forcings in intertidal mangrove sediments from Mayotte (Indo-West-Pacific), Martinique and Guadeloupe (Caribbean). Sediment cores were sampled at the end of the dry season at low tide on adult mangrove stands with similar immersion time. In each sediment layer, we analyzed redox potential, pH, porewater salinity, grain size, organic matter, metals, organic contaminants, prokaryotes and meiofauna. Our results show that sediments far from cities and agricultural fields trapped site-specific contaminants due to local water transport processes. Some metals, PAHs or pesticides exceeded toxicity thresholds in most of the studied stations, thus being harmful to benthic fauna. The sedimentary environment acts as a filter selecting specific meiofauna communities at station scale only in the Caribbean. In Mayotte, horizontal homogeneity contrasts with vertical heterogeneity of the sedimentary environment and the meiofauna. Nematode genera showed particular distribution patterns horizontally and vertically, suggesting the presence of sediment patches suitable for a restricted pool of genera on each island. Results in the Caribbean are consistent with nested diversity patterns due to environmental filtering. Conversely, horizontal homogeneity at Mayotte would reflect greater dispersal between stations or more spatially homogeneous anthropogenic pressures. The nematode genera present at depth may not be the most specialized, but the most versatile, capable of thriving in different conditions. Terschellingia and Daptonema showed contrasted responses to environmental forcing, likely due to their versatility, while Desmodora showed uniform responses between study areas, except when toxicity thresholds were exceeded. Our results emphasize that a given genus of nematode may respond differently to sedimentary conditions depending on sites.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Nematoides , Áreas Alagadas , Animais , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Região do Caribe , Guadalupe , Invertebrados
18.
Zootaxa ; 5410(1): 134-144, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38480252

RESUMO

There are very few taxonomic studies of Brazilian sipunculan worms, and the species occurring along the northern coasts are largely understudied. We report herein the occurrence of four shallow water species along the intertidal zones of Bahia and Pernambuco states. Antillesoma antillarum (Grbe & Oersted, 1858) occurs from underneath beach rocks or within sandstone reefs and may reach high densities. The large species Sipunculus (Sipunculus) nudus Linnaeus, 1766, Sipunculus polymyotus Fisher, 1947, and Xenosiphon branchiatus (Fischer, 1895) were collected in sandy-mud, low-energy intertidal environments. For the first time, we report that sipunculans are collected and used as fishing bait by local fishermen in the Western Atlantic. All species are fully described, including notes on their external and internal anatomy.


Assuntos
Anelídeos , Nematoides , Animais , Brasil
19.
Int J Parasitol Drugs Drug Resist ; 24: 100527, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447333

RESUMO

Haemonchus contortus and Trichostrongylus colubriformis are the most important gastrointestinal nematodes causing serious losses in sheep production of tropical and subtropical regions. Prophylaxis of gastrointestinal nematode infections is based on anthelmintics use, but their frequent administration selects multiple-resistant parasites. To evaluate how the situation has changed over the last decades, the anthelmintic resistance status of gastrointestinal nematodes in sheep flocks was assessed in the current study and compared to previous surveys. In each one of the 15 flocks evaluated, animals (n ≥ 7) were allocated into at least five groups and treated as follows: 1) untreated control; 2) albendazole; 3) levamisole; 4) ivermectin; and 5) monepantel. If more animals were available, two additional groups were included: 6) closantel, and 7) moxidectin. The faecal egg count reduction test (FECRT) was carried out to evaluate the pre- and post-treatment using the SHINY tool. Haemonchus spp. was the most prevalent nematode from faecal cultures. The mean efficacy of albendazole was 40%. Only in two farms, levamisole presented a relatively high percentage of reduction in the FECRT about 90%, while ivermectin and moxidectin presented the worst mean efficacy of 34% and 21% among all farms, respectively. Like other anthelmintics, closantel demonstrated low efficacy (63%) across all farms evaluated. Monepantel presented an overall mean efficacy of 79%, but it was the only anthelmintic that presented efficacy ≥95%, in five farms. The results revealed that gastrointestinal nematodes with multiple anthelmintic resistance were prevalent in all 15 sheep herds. The research suggests that nematodes are becoming more and more resistant to various anthelmintic compounds, which has made the problem worse. This circumstance highlights the necessity to put into practice sustainable and long-lasting methods to prevent gastrointestinal nematode infections in sheep husbandry.


Assuntos
Aminoacetonitrila/análogos & derivados , Anti-Helmínticos , Haemonchus , Macrolídeos , Nematoides , Infecções por Nematoides , Salicilanilidas , Doenças dos Ovinos , Animais , Ovinos , Levamisol/farmacologia , Levamisol/uso terapêutico , Ivermectina/uso terapêutico , Albendazol/uso terapêutico , Brasil/epidemiologia , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/veterinária , Fezes/parasitologia , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Contagem de Ovos de Parasitas/veterinária , Resistência a Medicamentos
20.
J Parasitol ; 110(2): 114-126, 2024 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-38503317

RESUMO

An inventory of parasites infecting the jaguar (Panthera onca) across its distribution range is relevant for the conservation of this threatened big cat. In this study, we report the occurrence of helminths in a jaguar from Mexico using morphological techniques (cleared and stained mounts and scanning electron microscopy) and partial sequences of the 28S ribosomal RNA (28S rRNA) gene and the cytochrome c oxidase 1 mitochondrial (COI) gene. We also provide an updated list of helminth species reported in jaguars in the Americas. Three helminth taxa are identified in the jaguar examined from Mexico: Toxocara cati, Physaloptera sp., and Taenia sp. The new 28S rRNA sequences of To. cati, Physaloptera sp., and Taenia sp. and the COI sequence of Taenia sp. corroborate the identity of the helminths isolated from this host. One hundred and twenty-nine records of helminths parasitizing jaguars from 49 studies up to May 2023 were identified in the Americas. In most of these studies (73.6%), helminths were identified using coproparasitological techniques. Sixteen helminths (7 nematodes, 5 cestodes, 3 acanthocephalans, and 1 trematode) were identified at the species level in free-ranging and captive jaguars. The study demonstrates the value of an integrative taxonomy approach to increase the accuracy of parasite identification in wildlife, especially when helminth specimens are scarce or poorly fixed.


Assuntos
Helmintos , Nematoides , Panthera , Animais , Panthera/genética , México/epidemiologia , RNA Ribossômico 28S/genética , Helmintos/genética
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