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1.
Parasitol Res ; 120(3): 963-970, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33501587

RESUMO

Capillariidae is a group of nematode parasites of vertebrates with a complex taxonomy. The structure of the eggshell, which was indicated as the most important characteristic for identification of genus or species through eggs, is very diverse among genera. The visualization and characterization of eggshell by light microscopy (LM) are a challenging task since different planes of the egg surface are needed. Nevertheless, categories of eggshell ornamentation were proposed by LM: smooth, punctuated, reticulated type I, and reticulated type II. The present study aimed to characterize the eggshell structure of Capillariidae species, parasites of mammals and avians, deposited in a helminthological collection using scanning electron microscopy (SEM). Institutional Biological Collections are taxonomic repositories of specimens described and strictly identified at the species level by systematics specialists. SEM eggshell images were obtained from 12 species belonging to 5 genera (Aonchotheca, Baruscapillaria, Capillaria, Echinocoleus, Eucoleus) and compared to their respective LM images. Eggshell patterns observed using SEM were associated categories of eggshell ornamentation previously proposed by LM images. The SEM data indicate that eggshell categories are not in agreement with capillariid genera or sites of infection. However, the study provides previously unknown SEM eggshell information from curated species, which contributes with a specific and supplementary taxonomic feature at the species level of Capillariidae.


Assuntos
Nematoides/ultraestrutura , Infecções por Nematoides/veterinária , Óvulo/ultraestrutura , Animais , Aves/parasitologia , Mamíferos/parasitologia , Microscopia Eletrônica de Varredura , Nematoides/classificação , Infecções por Nematoides/parasitologia , Especificidade da Espécie
2.
PLoS One ; 15(8): e0236143, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790679

RESUMO

The focus of gastro-intestinal parasite control in the sheep industry is increasingly on finding a balance between maintaining productivity of the flock whilst minimising selection for anthelmintic resistance to preserve anthelmintic efficacy for the future. Periparturient ewes represent the major source of gastro-intestinal parasites for growing lambs and are therefore a priority for parasite control. This study examines the impact on ewe faecal egg counts (FECs), lamb FECs, lamb daily live weight gains (DLWGs) and pasture larval counts of treating groups of ewes two weeks prior to lambing with either, a long-acting moxidectin treatment, short-acting doramectin or control. Six groups of twenty ewes were allocated to individual paddocks, two groups allocated to each treatment, and weekly faecal sampling was performed throughout from the ewes and from six weeks after the start of lambing in the lambs. Treatment group was found to have a significant effect on both ewe FEC (p<0.001) and lamb FEC (p = 0.001) with the group receiving the long-acting anthelmintic having the lowest ewe and lamb FECs. There was no significant effect on the DLWGs of the lambs. Pasture larval counts at the end of the study period were lowest in the long-acting wormer treatment group. The use of long-acting moxidectin may be helpful as part of a parasite control programme by reducing the worm burdens of ewes and their lambs, decreasing the number of anthelmintic treatments required in that year and by reducing pasture contamination for those sheep which will graze the pasture in the next year. However, like all anthelmintics, its use should be judicious to avoid selection for resistance.


Assuntos
Criação de Animais Domésticos/métodos , Anti-Helmínticos/administração & dosagem , Infecções por Nematoides/veterinária , Doenças dos Ovinos/tratamento farmacológico , Ovinos/parasitologia , Animais , Anti-Helmínticos/farmacocinética , Fazendas , Fezes/parasitologia , Feminino , Meia-Vida , Ivermectina/administração & dosagem , Ivermectina/análogos & derivados , Ivermectina/farmacocinética , Larva , Macrolídeos/administração & dosagem , Macrolídeos/farmacocinética , Nematoides/isolamento & purificação , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas/veterinária , Período Pós-Parto , Gravidez , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/parasitologia
3.
Rev Bras Parasitol Vet ; 29(3): e003220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32667501

RESUMO

Among the Nematodes of Cerdocyon thous, the genus Pterygodermatites is characteristic for presenting cuticular projections along the body, being mentioned in different hosts in South America, although there are no records of its occurrence in the Amazon Biome. To enable further exploration in terms of their morphology and morphometry, the nematodes collected from cadavers of C. thous were fixed and observed using bright field microscopy and scanning electron microscopy, revealing characteristics compatible with P. (Multipectines) affinis, thus contributing more information about the geographic distribution of the parasite, as well as knowledge of the helminthological fauna of wild mammals in the Brazilian Amazon.


Assuntos
Canidae , Infecções por Nematoides , Espirurídios , Distribuição Animal , Animais , Brasil , Canidae/parasitologia , Microscopia Eletrônica de Varredura , Infecções por Nematoides/parasitologia , Especificidade da Espécie , Espirurídios/ultraestrutura
4.
Rev Bras Parasitol Vet ; 29(2): e023519, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609248

RESUMO

An adult male puma (Puma concolor), hit by a car in an urban area, died three days later despite the therapeutic support provided. At necropsy, multiple firm nodules were identified in the gastric mucosa. The nodules were coated by an intact mucosa with a central opening from which reddish and cylindrical nematodes protruded into the lumen. Twenty-seven nematodes were retrieved for morphological and morphometric evaluations. During histopathological examination of the gastric tissue, the adult nematodes appear in longitudinal and transverse sections, surrounded by thick bands of collagen, interspersed with mixed inflammatory infiltrates. The nematodes had an eosinophilic cuticle with caudal serrated projections (bulbar type), coelomyarian musculature, pseudocoelom, and females with uterus containing numerous larvated eggs, characteristics consistent with the Cylicospirura genus. Morphologically, female nematodes had six large tricuspid teeth in the oral cavity and the vulva had an opening anterior to the esophagus-intestinal junction. Male nematodes had five pairs of small papillae near the tip of the tail. These findings were consistent with Cylicospirura felineus. This parasite should be included in the differential diagnosis of nodular gastric wall lesions in wild felids.


Assuntos
Gastrite , Nematoides , Puma , Animais , Doenças do Gato/parasitologia , Doenças do Gato/patologia , Gatos , Feminino , Gastrite/parasitologia , Gastrite/veterinária , Masculino , Nematoides/fisiologia , Infecções por Nematoides/parasitologia , Infecções por Nematoides/patologia , Infecções por Nematoides/veterinária , Puma/parasitologia
5.
Sci Rep ; 10(1): 7765, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385321

RESUMO

The rise of anthelmintic resistance worldwide has led to the development of alternative control strategies for gastrointestinal nematodes (GIN) infections, which are one of the main constraints on the health of grazing small ruminants. Presently, breeding schemes rely mainly on fecal egg count (FEC) measurements on infected animals which are time-consuming and requires expertise in parasitology. Identifying and understanding the role of immunoglobulins in the mechanisms of resistance could provide a more efficient and sustainable method of identifying nematode-resistant animals for selection. In this study we review the findings on immunoglobulin response to GIN in the literature published to date (june 2019) and discuss the potential to use immunoglobulins as biomarkers. The literature review revealed 41 studies which measured at least one immunoglobulin: 35 focused on lamb immune response (18 used non-naïve lambs) and 7 on yearlings. In this review we propose a conceptual model summarizing the role of immunoglobulins in resistance to GIN. We highlight the need for more carefully designed and documented studies to allow comparisons across different populations on the immunoglobulin response to GIN infection.


Assuntos
Biomarcadores , Resistência à Doença/imunologia , Gastroenteropatias/imunologia , Gastroenteropatias/parasitologia , Imunoglobulinas/imunologia , Infecções por Nematoides/imunologia , Infecções por Nematoides/parasitologia , Animais , Cabras , Isotipos de Imunoglobulinas/imunologia , Ruminantes , Ovinos
6.
Trop Anim Health Prod ; 52(5): 2213-2219, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32388661

RESUMO

Endoparasitic nematode infection could have negative impacts on performances of sheep and goats. However, supplementary protein and minerals can also affect nematodes. This paper reviews present information on the importance of protein and minerals supplementation as means to control nematode infection in small ruminants. Protein supplementation seems to improve host resilience by diverting metabolizable protein (MP) towards dealing with detrimental effects of the infection and thus improve production and reproductive performances of animal. A large body of evidence shows that supplementation of copper, iron, and zinc can also enhance host resistance against nematode infection as shown by decreased fecal egg count (FEC) and worm burdens. As such, protein and mineral supplementations can play a major role in sustainable control of parasitic nematode infection and thus reduce reliance on chemotherapic drugs.


Assuntos
Proteínas na Dieta/metabolismo , Doenças das Cabras/tratamento farmacológico , Minerais/metabolismo , Infecções por Nematoides/veterinária , Substâncias Protetoras/farmacologia , Doenças dos Ovinos/tratamento farmacológico , Ração Animal/análise , Animais , Dieta/veterinária , Proteínas na Dieta/administração & dosagem , Suplementos Nutricionais/análise , Doenças das Cabras/parasitologia , Cabras , Minerais/administração & dosagem , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
7.
Nat Commun ; 11(1): 1964, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32327641

RESUMO

Sex determination mechanisms often differ even between related species yet the evolution of sex chromosomes remains poorly understood in all but a few model organisms. Some nematodes such as Caenorhabditis elegans have an XO sex determination system while others, such as the filarial parasite Brugia malayi, have an XY mechanism. We present a complete B. malayi genome assembly and define Nigon elements shared with C. elegans, which we then map to the genomes of other filarial species and more distantly related nematodes. We find a remarkable plasticity in sex chromosome evolution with several distinct cases of neo-X and neo-Y formation, X-added regions, and conversion of autosomes to sex chromosomes from which we propose a model of chromosome evolution across different nematode clades. The phylum Nematoda offers a new and innovative system for gaining a deeper understanding of sex chromosome evolution.


Assuntos
Evolução Molecular , Nematoides/genética , Infecções por Nematoides/parasitologia , Cromossomos Sexuais/genética , Animais , Brugia Malayi/genética , Caenorhabditis elegans/genética , Mapeamento Cromossômico , Feminino , Regulação da Expressão Gênica , Genoma Helmíntico/genética , Humanos , Masculino , Nematoides/classificação , Sequências Repetitivas de Ácido Nucleico/genética , Processos de Determinação Sexual/genética
8.
Adv Parasitol ; 108: 175-229, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32291085

RESUMO

In the past two decades, significant progress has been made in the sequencing, assembly, annotation and analyses of genomes and transcriptomes of parasitic worms of socioeconomic importance. This progress has somewhat improved our knowledge and understanding of these pathogens at the molecular level. However, compared with the free-living nematode Caenorhabditis elegans, the areas of functional genomics, transcriptomics, proteomics and metabolomics of parasitic nematodes are still in their infancy, and there are major gaps in our knowledge and understanding of the molecular biology of parasitic nematodes. The information on signalling molecules, molecular pathways and microRNAs (miRNAs) that are known to be involved in developmental processes in C. elegans and the availability of some molecular resources (draft genomes, transcriptomes and some proteomes) for selected parasitic nematodes provide a basis to start exploring the developmental biology of parasitic nematodes. Indeed, some studies have identified molecules and pathways that might associate with developmental processes in related, parasitic nematodes, such as Haemonchus contortus (barber's pole worm). However, detailed information is often scant and 'omics resources are limited, preventing a proper integration of 'omic data sets and comprehensive analyses. Moreover, little is known about the functional roles of pheromones, hormones, signalling pathways and post-transcriptional/post-translational regulations in the development of key parasitic nematodes throughout their entire life cycles. Although C. elegans is an excellent model to assist molecular studies of parasitic nematodes, its use is limited when it comes to explorations of processes that are specific to parasitism within host animals. A deep understanding of parasitic nematodes, such as H. contortus, requires substantially enhanced resources and the use of integrative 'omics approaches for analyses. The improved genome and well-established in vitro larval culture system for H. contortus provide unprecedented opportunities for comprehensive studies of the transcriptomes (mRNA and miRNA), proteomes (somatic, excretory/secretory and phosphorylated proteins) and lipidomes (e.g., polar and neutral lipids) of this nematode. Such resources should enable in-depth explorations of its developmental biology at a level, not previously possible. The main aims of this review are (i) to provide a background on the development of nematodes, with a particular emphasis on the molecular aspects involved in the dauer formation and exit in C. elegans; (ii) to critically appraise the current state of knowledge of the developmental biology of parasitic nematodes and identify key knowledge gaps; (iii) to cover salient aspects of H. contortus, with a focus on the recent advances in genomics, transcriptomics, proteomics and lipidomics as well as in vitro culturing systems; (iv) to review recent advances in our knowledge and understanding of the molecular and developmental biology of H. contortus using an integrative multiomics approach, and discuss the implications of this approach for detailed explorations of signalling molecules, molecular processes and pathways likely associated with nematode development, adaptation and parasitism, and for the identification of novel intervention targets against these pathogens. Clearly, the multiomics approach established recently is readily applicable to exploring a wide range of interesting and socioeconomically significant parasitic worms (including also trematodes and cestodes) at the molecular level, and to elucidate host-parasite interactions and disease processes.


Assuntos
Biologia Computacional , Nematoides/crescimento & desenvolvimento , Nematoides/genética , Infecções por Nematoides/parasitologia , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Interações Hospedeiro-Parasita/fisiologia , Humanos , Parasitos/genética , Parasitos/crescimento & desenvolvimento
9.
Rev Bras Parasitol Vet ; 29(1): e015819, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32236331

RESUMO

An evaluation was made of the effect of anthelmintic treatments on the performance of Simmental X Nellore crossbred calves before and after weaning. To this end, the calves were divided into three groups: (1) treated monthly with a low efficacy anthelmintic drug, ivermectin; (2) treated monthly with a highly effective anthelmintic drug, albendazole; and (3) untreated control group. All the groups in this experiment showed an average fecal egg count of less than 400 eggs per gram (EPG), and no clinical signs of parasitic gastroenteritis. The blood variables were within the normal range and no calf presented anemia. In most of the samplings, mean EPGs were significantly lower (P<0.05) in the group treated with albendazole. The calves received dietary supplementation before and after weaning, which enabled them to gain weight in every month of the experiment and reach a body weight of about 250 kg on the last sampling date, before turning one year old. The anthelmintic treatments did not affect body weight gain, leading to the conclusion that, when fed with suitable dietary supplements, Simmental X Nellore crossbred calves are not affected by gastrointestinal nematode parasites acquired by grazing.


Assuntos
Albendazol/administração & dosagem , Anti-Helmínticos/administração & dosagem , Doenças dos Bovinos/tratamento farmacológico , Gastroenteropatias/veterinária , Ivermectina/administração & dosagem , Infecções por Nematoides/veterinária , Animais , Bovinos , Fezes/parasitologia , Feminino , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/parasitologia , Masculino , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas/veterinária
10.
Vet Parasitol ; 280: 109087, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32220696

RESUMO

Mixed grazing of breeding goats and cattle (goats to cattle ratio: about 50 %, based on metabolic weight) was monitored for 2 years on a rotational pasture with the two species grazing together, then for 5 years with cattle grazing immediately after goats. For both modalities, the level of goat parasite infection was not significantly different from that of the control groups. Nevertheless, the association allowed a slight improvement in kid growth and goat productivity, probably in relation to a better food quality. The response of adult goats to mixed grazing is therefore very different from that previously obtained with kids post-weaning. The question of the relationship between heterogeneity of pastures, knowledge of their environment, grazing behaviour of adult goats and risk of infection with gastrointestinal nematodes requires further investigation.


Assuntos
Criação de Animais Domésticos , Comportamento Alimentar , Doenças das Cabras/epidemiologia , Nematoides/fisiologia , Infecções por Nematoides/veterinária , Animais , Bovinos/fisiologia , Doenças das Cabras/parasitologia , Cabras/fisiologia , Pradaria , Guadalupe/epidemiologia , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia
11.
Acta Vet Scand ; 62(1): 9, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32024529

RESUMO

The study aimed to compare the gastrointestinal helminthofauna of free-ranging wild boars from arable lands and forests, which are the natural habitats for wild boar in Poland and further to investigate if wild boars living in agricultural environments could acquire helminths commonly detected in domestic pigs. In 2011-2014, a total of 57 wild boars were examined post-mortem for the presence of gastrointestinal nematodes. Altogether, all but two of the animals were infected, and seven nematode species were found. The mean infection burden was 68.9 parasites, ranging from 1 to 381 worms. In forest areas, Ascarops strongylina, Physocephalus sexalatus, and Globocephalus urosubulatus were common, whereas on arable lands, the animals were more frequently infected (P < 0.05) by Ascaris suum and Trichuris suis, which are parasites that commonly occur in domestic pigs. Oesophagostomum dentatum was observed only in wild boars on arable lands, and Bourgelatia diducta, which is alien to European suids, appeared irrespective of habitat type. These results show significant differences in parasite spectra among wild boars living in forests or arable lands in Poland and indicates the risks of parasite transfer from domestic pigs to free-ranging wild boars. Furthermore, in farmed game, organic farming, or in the case of agritourism farms, one should be aware of the risk of related animals acquiring new and alien parasite infections by being kept outdoors.


Assuntos
Trato Gastrointestinal/parasitologia , Infecções por Nematoides/veterinária , Sus scrofa/parasitologia , Doenças dos Suínos/parasitologia , Agricultura , Animais , Biodiversidade , Florestas , Nematoides/classificação , Nematoides/isolamento & purificação , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas/veterinária , Polônia , Suínos
12.
Vet Clin North Am Food Anim Pract ; 36(1): 45-57, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32029188

RESUMO

Control of gastrointestinal nematodes (GIN) can have both economic and health benefits for cattle operations in the southern United States. In the past several decades, GIN control has relied almost exclusively on the use of anthelmintics. With the increase in anthelmintic resistance new strategies must be developed. Anthelmintic use should be minimized by integrating grazing management and a good herd health program into GIN control programs. This takes knowledge of GIN biology and epidemiology in the region (climate and weather) combined with specific information from the ranch.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/prevenção & controle , Gastroenteropatias/veterinária , Infecções por Nematoides/veterinária , Animais , Anti-Helmínticos/administração & dosagem , Canadá/epidemiologia , Bovinos , Doenças dos Bovinos/parasitologia , Clima , Fezes/parasitologia , Gastroenteropatias/epidemiologia , Gastroenteropatias/parasitologia , Gastroenteropatias/prevenção & controle , Trato Gastrointestinal/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Infecções por Nematoides/prevenção & controle , Estados Unidos/epidemiologia
13.
Rev Bras Parasitol Vet ; 29(1): e013119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049139

RESUMO

The objective of this study was to evaluate the efficacy of carvacryl acetate (CVA) and nanoencapsulated CVA (nCVA) on gastrointestinal nematodes of sheep. The CVA was nanoencapsulated with chitosan/gum arabic and the efficacy of nanoencapsulation (EE), yield, zeta potential, nanoparticle morphology and release kinetics at pH 3 and 8 were analyzed. Acute and subchronic toxicity were evaluated in rodents and reduction of egg counts in the faeces (FECRT) of sheep. The sheep were divided into four groups (n = 10): G1, 250 mg/kg CVA; G2, 250 mg/kg nCVA; G3, polymer matrix and G4: 2.5 mg/kg monepantel. EE and nCVA yield were 65% and 57%, respectively. The morphology of the nanoparticles was spherical, size (810.6±286.7 nm), zeta potential in pH 3.2 (+18.3 mV) and the 50% release of CVA at pHs 3 and 8 occurred at 200 and 10 h, respectively. nCVA showed LD50 of 2,609 mg/kg. CVA, nCVA and monepantel reduced the number of eggs per gram of faeces (epg) by 57.7%, 51.1% and 97.7%, respectively. The epg of sheep treated with CVA and nCVA did not differ from the negative control (P>0.05). Nanoencapsulation reduced the toxicity of CVA; however, nCVA and CVA presented similar results in the FECRT.


Assuntos
Anti-Helmínticos/administração & dosagem , Trato Gastrointestinal/parasitologia , Monoterpenos/administração & dosagem , Nanocápsulas/administração & dosagem , Nematoides/efeitos dos fármacos , Infecções por Nematoides/tratamento farmacológico , Doenças dos Ovinos/tratamento farmacológico , Animais , Anti-Helmínticos/toxicidade , Fezes/parasitologia , Feminino , Camundongos , Monoterpenos/toxicidade , Nanocápsulas/toxicidade , Nematoides/classificação , Nematoides/isolamento & purificação , Infecções por Nematoides/parasitologia , Contagem de Ovos de Parasitas , Testes de Sensibilidade Parasitária , Reação em Cadeia da Polimerase em Tempo Real , Roedores , Ovinos , Doenças dos Ovinos/parasitologia , Testes de Toxicidade
14.
Rev Bras Parasitol Vet ; 29(1): e014619, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049140

RESUMO

Parasitic myelopathy caused by Gurltia paralysans in domestic cats is a disease commonly reported in several South American countries. The adult parasite is lodged in the meningeal veins and spinal cord, often causing clinical manifestations of vascular proliferation, thrombophlebitis, and medullary compression. Wild felines are believed to be the definitive hosts of this parasite. The infection occurs through the ingestion of paratenic hosts, but the life cycle of G. paralysans is not yet clearly understood. In this paper, we discuss a case of parasitic myelopathy in a margay (Leopardus wiedii) that died during post-surgical care. Necropsy revealed focal hemorrhages in the thoracolumbar spinal cord. A microscopic examination revealed adult nematodes and eggs inside the veins of subarachnoid space in spinal cord, suggesting G. paralysans infection. This is first description of parasitic myelopathy in a margay in Brazil.


Assuntos
Felidae/parasitologia , Nematoides/isolamento & purificação , Infecções por Nematoides/veterinária , Doenças da Medula Espinal/parasitologia , Animais , Animais Selvagens , Brasil , Gatos , Felidae/classificação , Feminino , Nematoides/classificação , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/parasitologia , Doenças da Medula Espinal/diagnóstico
16.
J Helminthol ; 94: e115, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31931890

RESUMO

Drug resistance to helminth parasites is one of the most serious problems to threaten the livestock industry. The problem also poses a major threat to public health. Therefore, novel and safe agents should urgently be investigated to control parasitic infections. The current study was conducted to evaluate the possible antiparasitic effects of zinc oxide nanoparticles (ZnO-NPs) on one of the most prevalent gastrointestinal nematodes, Teladorsagia circumcincta. The worms were incubated with various concentrations of ZnO-NPs: 1, 4, 8, 12 and 16 ppm for 24 hours. Mobility and mortality of the parasites were recorded at four-hour intervals. At the endpoint, several biomarkers of oxidative/nitrosative stress, including superoxide dismutase, glutathione peroxidase and catalase, as well as lipid peroxidation, protein carbonylation, total antioxidant status, nitric oxide contents and DNA damage, were measured in the homogenized samples. ZnO-NPs showed significant anthelminthic effects, depending on time and concentration. Furthermore, the nanoparticle induced severe oxidative/nitrosative stress and DNA damage. ZnO-NPs could be considered as a novel and potent anthelminthic agent.


Assuntos
Anti-Helmínticos/farmacologia , Infecções por Nematoides/veterinária , Óxido de Zinco/farmacologia , Animais , Biomarcadores Farmacológicos , Dano ao DNA , Gado/parasitologia , Nanopartículas/parasitologia , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Estresse Oxidativo
17.
Int J Mol Sci ; 21(2)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936278

RESUMO

In plant immune responses, reactive oxygen species (ROS) act as signaling molecules that activate defense pathways against pathogens, especially following resistance (R) gene-mediated pathogen recognition. Glutathione (GSH), an antioxidant and redox regulator, participates in the removal of hydrogen peroxide (H2O2). However, the mechanism of GSH-mediated H2O2 generation in soybeans (Glycine max (L.) Merr.) that are resistant to the soybean cyst nematode (SCN; Heterodera glycines Ichinohe) remains unclear. To elucidate this underlying relationship, the feeding of race 3 of H. glycines with resistant cultivars, Peking and PI88788, was compared with that on a susceptible soybean cultivar, Williams 82. After 5, 10, and 15 days of SCN infection, we quantified γ-glutamylcysteine (γ-EC) and (homo)glutathione ((h)GSH), and a gene expression analysis showed that GSH metabolism in resistant cultivars differed from that in susceptible soybean roots. ROS accumulation was examined both in resistant and susceptible roots upon SCN infection. The time of intense ROS generation was related to the differences of resistance mechanisms in Peking and PI88788. ROS accumulation that was caused by the (h)GSH depletion-arrested nematode development in susceptible Williams 82. These results suggest that (h)GSH metabolism in resistant soybeans plays a key role in the regulation of ROS-generated signals, leading to resistance against nematodes.


Assuntos
Resistência à Doença/genética , Glutationa/genética , Infecções por Nematoides/genética , Soja/genética , Animais , Genótipo , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , Infecções por Nematoides/metabolismo , Infecções por Nematoides/parasitologia , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Espécies Reativas de Oxigênio/metabolismo , Soja/crescimento & desenvolvimento , Soja/parasitologia
18.
Parasitol Res ; 119(2): 529-543, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31834492

RESUMO

Standard diagnostic methods currently in use for the identification of helminth infections in ruminants are based on the morphological analysis of immature and adult stages of parasites. This paper describes a method for the semiquantitative identification of nematodes, mainly Trichostrongyloidea, at species-level resolution. The method is based on amplification and fragment analysis followed by minisequencing of the ITS-2 region (internal transcribed spacer 2) of the ribosomal DNA of parasite eggs or larvae. This method allows for the identification of seven genera (Chabertia, Cooperia, Haemonchus, Oesophagostomum, Ostertagia, Teladorsagia, and Trichostrongylus) and 12 species (Chabertia ovina, Cooperia curticei, Cooperia punctata, Cooperia oncophora/Cooperia surnabada, Haemonchus contortus, Haemonchus placei, Haemonchus longistipes, Oesophagostomum asperum, Oesophagostomum radiatum, Ostertagia ostertagi, Trichostrongylus axei, and Trichostrongylus colubriformis) of infectious nematodes of domestic ruminants. The concordance between the morphological and molecular analyses in the detection of genera ranged from 0.84 to 0.99, suggesting the proposed detection method is specific, semiquantitative, less laborious, and highly cost-efficient.


Assuntos
Infecções por Nematoides/veterinária , Ruminantes/parasitologia , Trichostrongyloidea/isolamento & purificação , Animais , Bovinos , Doenças dos Bovinos/parasitologia , DNA de Helmintos , DNA Ribossômico , Cabras , Haemonchus/genética , Haemonchus/isolamento & purificação , Infecções por Nematoides/parasitologia , Técnicas de Amplificação de Ácido Nucleico/veterinária , Oesophagostomum/genética , Oesophagostomum/isolamento & purificação , Ostertagia/genética , Ostertagia/isolamento & purificação , Ovinos , Strongyloidea/genética , Trichostrongyloidea/genética , Trichostrongylus/genética
19.
Mol Ecol Resour ; 20(1): 318-332, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31721426

RESUMO

Ribosomal RNA genes have long been a favoured locus in phylogenetic and metabarcoding studies. Within a genome, rRNA loci are organized as tandem repeated arrays and the copies are homogenized through the process of concerted evolution. However, some level of rRNA variation (intragenomic polymorphism) is known to persist and be maintained in the genomes of many species. In nematode worms, the extent of rRNA polymorphism (RP) across species and the evolutionary and life history factors that contribute to the maintenance of intragenomic RP is largely unknown. Here, we present an extensive analysis across 30 terrestrial nematode species representing a range of free-living and parasitic taxa isolated worldwide. Our results indicate that RP is common and widespread, ribosome function appears to be maintained despite mutational changes, and intragenomic variants are stable in the genome and neutrally evolving. However, levels of variation were varied widely across rRNA locus and species, with some taxa observed to lack RP entirely. Higher levels of RP were significantly correlated with shorter generation time and high reproductive rates, and population-level factors may play a role in the geographic and phylogenetic structuring of rRNA variants observed in genera such as Rotylenchulus and Pratylenchus. Although RP did not dramatically impact the clustering and recovery of taxa in mock metabarcoding analyses, the present study has significant implications for global biodiversity estimates of nematode species derived from environmental rRNA amplicon studies, as well as our understanding of the evolutionary and ecological factors shaping genetic diversity across the nematode Tree of Life.


Assuntos
DNA de Helmintos/genética , Nematoides/genética , Filogenia , Polimorfismo Genético , RNA Ribossômico/genética , Animais , Ecossistema , Evolução Molecular , Fezes/parasitologia , Humanos , Nematoides/classificação , Nematoides/isolamento & purificação , Infecções por Nematoides/parasitologia , Infecções por Nematoides/veterinária , Solo/parasitologia
20.
Trends Parasitol ; 36(1): 52-63, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31734099

RESUMO

Spirocerca lupi is a nematode transmitted by dung beetles that infects domestic and wild canids in tropical and subtropical regions and is associated with neoplasia. It produces a distinctive pathology with the formation of esophageal nodules classified as inflammatory, preneoplastic, or neoplastic with metastasis to distant organs. Aberrant central nervous system migration of this nematode is also responsible for severe neurological manifestations. Reports of spirocercosis have increased over the last two decades showing spread of this canine helminth in five continents. S. lupi from different geographical locations is genetically distinct with two genotypes, genotype I from Africa, Asia, and Australia, and genotype II from Europe, and recently separated from Spirocerca vulpis, a new species described in red foxes from Europe.


Assuntos
Doenças do Cão/parasitologia , Infecções por Nematoides/veterinária , Animais , Doenças do Cão/patologia , Cães , Genótipo , Infecções por Nematoides/parasitologia , Infecções por Nematoides/patologia , Thelazioidea/classificação , Thelazioidea/genética
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