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1.
J Invertebr Pathol ; 204: 108123, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705354

RESUMO

Entomopathogenic nematodes (EPNs) can control several important turfgrass insect pests including white grubs, weevils, cutworms, and sod webworms. But most of the research has focused on inundative releases in a biopesticide strategy using EPN strains that may have lost some of their ability to persist effectively over years of lab maintenance and / or selection for virulence and efficient mass-production. Our study examined the potential of fresh field isolate mixes of endemic EPNs to provide multi-year suppression of turfgrass insect pests. In early June 2020, we applied isolate mixes from golf courses of the EPNs Steinernema carpocapsae, Heterorhabditis bacteriophora, and their combination to plots straddling fairway and rough on two golf courses in central New Jersey, USA. Populations of EPNs and insect pests were sampled on the fairway and rough side of the plots from just before EPN application until October 2022. EPN populations increased initially in plots treated with the respective species. Steinernema carpocapsae densities stayed high for most of the experiment. Heterorhabditis bacteriophora densities decreased after 6 months and stabilized at lower levels. Several insect pests were reduced across the entire experimental period. In the fairway, the combination treatment reduced annual bluegrass weevil larvae (59 % reduction) and adults (74 %); S. carpocapsae reduced only adults (42 %). White grubs were reduced by H. bacteriophora (67 %) and the combination (63 %). Black turfgrass ataenius adults were reduced in all EPN treatments (43-62 %) in rough and fairway. Sod webworm larvae were reduced by S. carpocapsae in the fairway (75 %) and the rough (100 %) and by H. bacteriophora in the rough (75 %). Cutworm larvae were reduced in the fairway by S. carpocapsae (88 %) and the combination (75 %). Overall, our observations suggest that inoculative applications of fresh field isolate mixes of endemic EPNs may be a feasible approach to long-term suppression of insect pests in turfgrass but may require periodic reapplications.


Assuntos
Controle Biológico de Vetores , Rabditídios , Animais , Rabditídios/fisiologia , Poaceae/parasitologia , Mariposas/parasitologia , Gorgulhos/parasitologia , New Jersey
2.
PLoS One ; 16(2): e0246855, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33592028

RESUMO

Precision agriculture (PA) is the application of management decisions based on identifying, quantifying, and responding to space-time variability. However, knowledge of crop pest responses to within-field environmental variability, and the spatial distribution of their natural enemies, is limited. Quantitative methods providing insights on how pest-predator relationships vary within fields are potentially important tools. In this study, phloem feeders and their natural enemies, were observed over two years across 81 locations within a field of the perennial feedstock grass in Georgia, USA. Geographically weighted regression (GWR) was used to spatially correlate their abundance with environmental factors. Variables included distance to forest edge, Normalized Difference of Vegetation Index (NDVI), slope, aspect, elevation, soil particle size distribution, and weather values. GWR methods were compared with generalized linear regression methods that do not account for spatial information. Non-spatial models indicated positive relationships between phloem-feeder abundance and wind speed, but negative relationships between elevation, proportions of silt and sand, and NDVI. With data partitioned into three seasonal groups, terrain and soil variables remained significant, and natural enemies and spiders became relevant. Results from GWR indicated that magnitudes and directions of responses varied within the field, and that relationships differed among seasons. Strong negative relationships between response and explanatory factors occurred: with NDVI during mid-season; with percent silt, during mid-, and late seasons; and with spider abundance during early and late seasons. In GWR models, slope, elevation, and aspect were mostly positive indicating further that associations with elevation depended on whether models incorporated spatial information or not. By using spatially explicit models, the analysis provided a complex, nuanced understanding of within-field relationships between phloem feeders and environmental covariates. This approach provides an opportunity to learn about the variability within agricultural fields and, with further analysis, has potential to inform and improve PA and habitat management decisions.


Assuntos
Produtos Agrícolas , Herbivoria , Insetos/fisiologia , Modelos Biológicos , Poaceae , Agricultura , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/parasitologia , Georgia , Poaceae/crescimento & desenvolvimento , Poaceae/parasitologia
3.
Parasit Vectors ; 13(1): 458, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912326

RESUMO

BACKGROUND: The ability of infective larvae of cattle gastrointestinal nematode (GIN) species to overwinter on pastures in northerly climatic zones with very cold dry winters is poorly understood. This is an important knowledge gap with critical implications for parasite risk assessment and control. METHODS: Infective third-stage larvae (L3) were quantified in samples of fecal pats, together with adjacent grass and soil, before and after winter on three farms in southern, central and northern Alberta. Nemabiome ITS2 metabarcoding was then performed on the harvested L3 populations to determine the species composition. Finally, parasite-free tracer calves were used to investigate if the L3 surviving the winter could infect calves and develop to adult worms in spring. RESULTS: Farm level monitoring, using solar powered weather stations, revealed that ground temperatures were consistently higher, and less variable, than the air temperatures; minimum winter air and ground temperatures were - 32.5 °C and - 24.7 °C respectively. In spite of the extremely low minimum temperatures reached, L3 were recovered from fecal pats and grass before and after winter with only a 38% and 61% overall reduction over the winter, respectively. Nemabiome ITS2 metabarcoding assay revealed that the proportion of L3 surviving the winter was high for both Cooperia oncophora and Ostertagia ostertagi although survival of the former species was statistically significantly higher than the latter. Nematodirus helvetinaus and Trichostrongylus axei could be detected after winter whereas Haemonchus placei L3 could not overwinter at all. Adult C. oncophora, O. ostertagi and N. helvetianus could be recovered from tracer calves grazing after the winter. CONCLUSIONS: The largest proportion of L3 were recovered from fecal pats suggesting this is important refuge for L3 survival. Results also show that L3 of several GIN parasite species can survive relatively efficiently on pastures even in the extreme winter conditions in western Canada. Tracer calf experiments confirmed that overwintered L3 of both C. oncophora and O. ostertagi were capable of establishing a patent infection in the following spring. These results have important implications for the epidemiology, risk of production impact and the design of effective control strategies. The work also illustrates the value of applying ITS2 nemabiome metabarcoding to environmental samples.


Assuntos
Doenças dos Bovinos/parasitologia , DNA Intergênico/genética , Trato Gastrointestinal/parasitologia , Larva/crescimento & desenvolvimento , Nematoides/genética , Infecções por Nematoides/veterinária , Animais , Canadá , Bovinos , Doenças dos Bovinos/fisiopatologia , DNA de Helmintos/genética , DNA Ribossômico/genética , Fezes/parasitologia , Feminino , Larva/classificação , Larva/genética , Masculino , Nematoides/classificação , Nematoides/crescimento & desenvolvimento , Nematoides/isolamento & purificação , Infecções por Nematoides/parasitologia , Infecções por Nematoides/fisiopatologia , Poaceae/parasitologia , Estações do Ano , Solo/parasitologia
4.
Vet Parasitol ; 285: 109218, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32841785

RESUMO

The parasitic liver fluke, Fasciola hepatica, has a detrimental impact on food security and poses a welfare concern to ruminant livestock. F. hepatica metacercariae, shed from an intermediate mud snail host, encyst on vegetation and present a source of infection to grazing livestock. Feeding grass silage to ruminants is a common practice, however the role it plays in the transmission of F. hepatica remains largely unknown. Our current understanding relies on historical studies that are not representative of current silage production and did not apply molecular methods to detect F. hepatica DNA persistence within silages. This study determined the impact of specific fermentation factors, including grass dry matter (DM) content (20, 30 & 40 %), length of ensiling period and maintaining an anaerobic environment on F. hepatica metacercariae viability. In vitro excystment assays demonstrated that regardless of grass DM content, metacercariae ensiled under anaerobic conditions were not viable from two weeks post-sealing. Metacercariae recovered from ensiled grass of 20 % DM content subjected to aerobic spoilage, remained viable for up to 10 weeks. DNA of F. hepatica remained detectable for up to 10 weeks in both anaerobic and spoiled silages. This study highlights i) the importance of maintaining an anaerobic ensiling environment to eliminate the risk of F. hepatica transmission from silage and ii) an inverse relationship between grass DM content and duration of metacercariae survival within spoiled silages. Improving our understanding of trematode metacercariae survival rates within silages, especially of highly pathogenic species such as F. hepatica, allows farmers to make informed decisions regarding on-farm parasite control.


Assuntos
Fasciola hepatica/fisiologia , Fasciolíase/veterinária , Fermentação , Metacercárias/fisiologia , Poaceae/metabolismo , Poaceae/parasitologia , Silagem/parasitologia , Anaerobiose , Animais , Fasciolíase/prevenção & controle
5.
PLoS One ; 14(10): e0224482, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31665151

RESUMO

Climate change is affecting interactions among species, including host-parasite interactions. The effects of warming are of particular interest for interactions in which parasite and host physiology are intertwined, such as those between parasitic plants and their hosts. However, little is known about how warming will affect plant parasitic interactions, hindering our ability to predict how host and parasite species will respond to climate change. Here, we test how warming affects aboveground and belowground biomass of a hemiparasitic species (Castilleja sulphurea) and its host (Bouteloua gracilis), asking whether the effects of warming depend on the interaction between these species. We also measured how warming affected the number of haustorial connections between parasite and host. We grew each species alone and together under ambient and warmed conditions. Hosts produced more belowground biomass under warming. However, host biomass was reduced when plants were grown with a hemiparasite. Thus, parasitism negated the benefit of warming on belowground growth of the host. Host resource allocation to roots versus shoots also changed in response to both interaction with the parasite and warming, with hosts producing more root biomass relative to shoot biomass when grown with a parasite and when warmed. As expected, hemiparasite biomass was greater when grown with a host. Warmed parasites had lower root:shoot ratios but only when grown with a host. Under elevated temperatures, hemiparasite aboveground biomass was marginally greater, and plants produced significantly more haustoria. These findings indicate that warming can influence biomass production, both by modifying the interaction between host plants and hemiparasites and by affecting the growth of each species directly. To predict how species will be affected, it is important to understand not only the direct effects of warming but also the indirect effects that are mediated by species interactions. Ultimately, understanding how climate change will affect species interactions is key to understanding how it will affect individual species.


Assuntos
Mudança Climática , Orobanchaceae/fisiologia , Poaceae/parasitologia , Biomassa , Aquecimento Global , Interações Hospedeiro-Parasita , Raízes de Plantas/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , Temperatura
6.
Rev Bras Parasitol Vet ; 28(3): 528-532, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31483029

RESUMO

The nematicidal effect of different organic materials was evaluated in order to develop a non-chemical alternative soil treatment for control of the free-living stages of small ruminant gastrointestinal nematodes. The selected organic materials were residues from the juice industry of acerola, cashew, grape, guava, papaya and pineapple, as well as castor residue from the biodiesel industry. LC90 results showed that pineapple residue was the most efficient inhibitor of larval development, followed by castor, grape, cashew, acerola, guava and papaya. Castor residue was also a good source of nitrogen and was used in a greenhouse experiment to prevent larval development in contaminated goat faeces that was deposited in pots containing the grasses Brachiaria brizantha (var. Paiaguás) or Megathyrsus maximus x M. infestum (var. Massai). Castor residue caused a significant (P < 0.05) reduction (85.04%) in Paiaguás grass contamination (L3.dry mass-1) and a reduction of 17.35% in Massai grass contamination (P > 0.05), with an increase in the biomass production of Massai (251.43%, P < 0.05) and Paiaguás (109.19%, P > 0.05) grasses. This strategy, called Econemat®, with good results in vitro shows to be promising on pasture increasing phytomass production.


Assuntos
Produção Agrícola , Sucos de Frutas e Vegetais , Nematoides/efeitos dos fármacos , Óleos de Plantas/farmacologia , Poaceae/parasitologia , Eliminação de Resíduos , Ricinus/química , Animais , Ruminantes
7.
Naturwissenschaften ; 106(9-10): 50, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31456022

RESUMO

The cavities of bamboos (Poaceae) are used by various animals. Most of the animals access these cavities either by existing cracks or by excavating bamboos with soft walls or small, thin-walled bamboos. Only a few animals excavate into the cavities of large and thick- and hard-walled internodes of mature bamboos. We studied two lizard beetle species (Coleoptera: Erotylidae: Languriinae), Doubledaya ruficollis and Oxylanguria acutipennis, that excavate into large internode cavities of recently dead mature bamboos and have morphological modifications. We observed that females of D. ruficollis used their mandibles to bore oviposition holes on Schizostachyum sp. (mean wall thickness = 3.00 mm) and O. acutipennis did so on Dendrocalamus sp. (3.37 mm) bamboos. Previous studies suggested that the markedly asymmetrical mandibles and needle-like ovipositors of females in the genus Doubledaya are adaptive traits for excavating hard-walled bamboos for oviposition. Therefore, we measured their mandibular lengths and ovipositor lengths. D. ruficollis females had greater asymmetry in the mandibles and shorter and less-sclerotized ovipositors than females of congeners using small bamboos. In contrast, O. acutipennis females had slightly asymmetrical mandibles and elongated, well-sclerotized ovipositors. Oviposition holes of D. ruficollis were cone-shaped (evenly tapering), whereas those of O. acutipennis were funnel-shaped (tube-like at the internal apex). This suggests that D. ruficollis females excavate oviposition holes using the mandibles only, and O. acutipennis females use both the mandibles and ovipositors. These differences suggest different oviposition-associated morphological specialization for using large bamboos: the extremely asymmetrical mandibles in D. ruficollis and elongated, needle-like ovipositors in O. acutipennis.


Assuntos
Besouros/anatomia & histologia , Besouros/fisiologia , Estruturas Animais/anatomia & histologia , Animais , Comportamento Animal/fisiologia , Feminino , Tamanho do Órgão/fisiologia , Poaceae/anatomia & histologia , Poaceae/parasitologia
8.
Sci Rep ; 9(1): 10284, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311958

RESUMO

Several herbivorous insects utilize plant chemical cues to identify hosts for feeding. The role of smell in host plant detection by Mahanarva spectabilis (Distant) remains largely unknown. In this study, assays were applied to assess M. spectabilis olfactory responses to forage grasses (Pennisetum purpureum cvs. Roxo Botucatu and Pioneiro; Panicum maximum cvs. Makueni and Tanzânia; Hyparrhenia rufa cv. Jaraguá; Melinis minutiflora; Cynodon dactylon cv. Tifton; Brachiaria brizantha cv. Marandú; and Brachiaria decumbens cv. Basilisk). Bioassays were performed using a Y-olfactometer to evaluate the behavior of adult M. spectabilis to forage damaged and undamaged by insects. M. spectabilis preferred volatiles of undamaged Basilisk and Pioneiro. Repellent behavior by M. spectabilis to cospecifics was recorded for plant volatiles from damaged Marandú. The mixture of volatiles from undamaged forage grasses differed from that of forage grasses damaged by insects. Forage grasses showed a greater diversity of compounds after damage, including menthone, eucalyptol and camphor, which are compounds likely to cause loss of attractiveness or repellence. Our results demonstrate that M. spectabilis employs plant chemical cues in its choice of hosts. This fact may contribute to strategies of integrated management against this pest.


Assuntos
Hemípteros/fisiologia , Poaceae/química , Olfato/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Hemípteros/efeitos dos fármacos , Herbivoria , Interações Hospedeiro-Parasita , Repelentes de Insetos/farmacologia , Percepção Olfatória , Extratos Vegetais/farmacologia , Poaceae/parasitologia
9.
Rev. bras. parasitol. vet ; 28(3): 528-532, July-Sept. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1042537

RESUMO

Abstract The nematicidal effect of different organic materials was evaluated in order to develop a non-chemical alternative soil treatment for control of the free-living stages of small ruminant gastrointestinal nematodes. The selected organic materials were residues from the juice industry of acerola, cashew, grape, guava, papaya and pineapple, as well as castor residue from the biodiesel industry. LC90 results showed that pineapple residue was the most efficient inhibitor of larval development, followed by castor, grape, cashew, acerola, guava and papaya. Castor residue was also a good source of nitrogen and was used in a greenhouse experiment to prevent larval development in contaminated goat faeces that was deposited in pots containing the grasses Brachiaria brizantha (var. Paiaguás) or Megathyrsus maximus x M. infestum (var. Massai). Castor residue caused a significant (P < 0.05) reduction (85.04%) in Paiaguás grass contamination (L3.dry mass-1) and a reduction of 17.35% in Massai grass contamination (P > 0.05), with an increase in the biomass production of Massai (251.43%, P < 0.05) and Paiaguás (109.19%, P > 0.05) grasses. This strategy, called Econemat®, with good results in vitro shows to be promising on pasture increasing phytomass production.


Resumo O efeito nematicida de diferentes materiais orgânicos foi avaliado, com o objetivo de desenvolver um tratamento alternativo não químico do solo para o controle dos estágios de vida livre de nematoides gastrintestinais de pequenos ruminantes. Os materiais orgânicos selecionados foram resíduos da indústria de suco de acerola, caju, uva, goiaba, mamão e abacaxi, além do resíduo de mamona da indústria de biodiesel. Os resultados da LC90 mostraram que o resíduo de abacaxi foi o mais eficiente inibidor do desenvolvimento larval, seguido pela mamona, uva, caju, acerola, goiaba e mamão. O resíduo de mamona também se mostrou uma boa fonte de nitrogênio, sendo usado em experimento em casa de vegetação para prevenir o desenvolvimento larval em fezes contaminadas, depositadas em vasos, contendo as gramíneas Brachiaria brizantha (var. Paiaguás) ou Megathyrsus maximus x M. infestum (var. Massai). O resíduo de mamona reduziu (85,04%) significativamente (P < 0,05) a contaminação no capim-Paiaguás (L3.dry massa-1), 17,35% no capim Massai (P> 0,05), e aumentou a produção de biomassa das gramíneas Massai (251,43%, P <0,05) e Paiaguás (109,19%, P> 0,05). Essa estratégia, chamada Econemat®, com bons resultados in vitro, mostra-se promissora nas pastagens aumentando a produção de fitomassa.


Assuntos
Animais , Ricinus/química , Óleos de Plantas/intoxicação , Eliminação de Resíduos , Sucos de Frutas e Vegetais , Produção Agrícola , Poaceae/parasitologia , Nematoides/efeitos dos fármacos , Ruminantes
10.
Arch Insect Biochem Physiol ; 100(4): e21537, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30666693

RESUMO

Planthoppers are highly destructive pests that damage rice plants by feeding and transmitting viruses. They feed on phloem sap using specialized mouthparts and secrete saliva during feeding. Over the past decade, genomic, transcriptomic, and proteomic approaches have greatly improved our understanding of the complexity of planthopper saliva, and have provided a glimpse of planthopper-plant interactions. Here we focus on a few recent advances in planthopper saliva and discuss how salivary components influence planthopper performance. Understanding the molecular basis of saliva in planthopper-plant interactions will provide evolutionary insights, and promote the development of novel strategies for controlling agricultural pests.


Assuntos
Líquidos Corporais/fisiologia , Regulação da Expressão Gênica/fisiologia , Hemípteros/fisiologia , Proteínas de Insetos , Animais , Interações Hospedeiro-Parasita , Poaceae/parasitologia
11.
Med Vet Entomol ; 32(4): 473-480, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30194860

RESUMO

The red sheep tick, Haemaphysalis punctata (Ixodida: Ixodidae), has been reported as present in the U.K. for more than a century; however, very little has been written about its distribution. In recent years, numbers of detections of this tick species reported to the Public Health England (PHE) Tick Surveillance Scheme have increased. This rise in the number of records may be attributable to increased tick surveillance activities or to the increased distribution of this species of tick in parts of England. This paper reviews published reports of H. punctata and all data held by the Biological Records Centre and PHE, and summarizes a number of field studies conducted by PHE and the Animal and Plant Health Agency over the past 8 years. It would appear from the evidence presented here that H. punctata may be expanding its range across the eastern part of the South Downs National Park, where there have also been reports of this tick species biting humans. It is possible that the movement of sheep between grassland sites is facilitating this spread. Further studies that better elucidate the ecology of this tick and its possible role as a vector of human and veterinary diseases are now warranted.


Assuntos
Doenças das Aves/parasitologia , Ixodidae/fisiologia , Passeriformes/parasitologia , Coelhos/parasitologia , Doenças dos Ovinos/parasitologia , Infestações por Carrapato/veterinária , Animais , Doenças das Aves/epidemiologia , Inglaterra/epidemiologia , Feminino , Humanos , Masculino , Poaceae/parasitologia , Ovinos , Doenças dos Ovinos/epidemiologia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/parasitologia , País de Gales/epidemiologia
12.
Exp Parasitol ; 193: 27-32, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30053398

RESUMO

Duddingtonia flagrans is a natural strain of Nematophagous-Fungi isolated around the world. It has demonstrated efficacy and ease of use in laboratory as well as in field conditions. The fungus contributes to the prophylactic control of the worms by reducing the number of L3 on pasture. The aims of this study were to test and analyze the predatory effect of D. flagrans under sunny and shaded conditions on the L3 in the faeces, and to verify the reduction of translation to pasture during summer and winter seasons. Faecal Mass Units (FMUs) were assigned to two treated groups (groups treated with D. flagrans chlamydospores, TG) and two untreated groups (without D. flagrans chlamydospores, UG), in summer and winter, under sunny and shaded conditions. FMUs and herbage samples were taken for parasitological workup. Predatory activity of D. flagrans was evident under both conditions for the summer experiment but was not manifest for the winter experiment. In summer, an interaction between sunny and shaded conditions and predatory activity of D. flagrans was found. Environmental conditions on predatory activity should be considered when designing strategies for the implementation of D. flagrans in grazing systems to smooth the infectivity curve of L3.


Assuntos
Doenças dos Bovinos/parasitologia , Duddingtonia/fisiologia , Enteropatias Parasitárias/veterinária , Nematoides/microbiologia , Luz Solar , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Duddingtonia/efeitos da radiação , Fezes/parasitologia , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/prevenção & controle , Larva/microbiologia , Contagem de Ovos de Parasitas/veterinária , Controle Biológico de Vetores/métodos , Controle Biológico de Vetores/normas , Poaceae/parasitologia , Comportamento Predatório/efeitos da radiação , Chuva , Estações do Ano , Temperatura
13.
Parasit Vectors ; 11(1): 342, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29884202

RESUMO

BACKGROUND: Increasing trematode prevalence and disease occurrence in livestock is a major concern. With the global spread of anthelmintic resistant trematodes, future control strategies must incorporate approaches focusing on avoidance of infection. The reliance of trematodes on intermediate snail hosts to successfully complete their life-cycle means livestock infections are linked to the availability of respective snail populations. By identifying intermediate snail host habitats, infection risk models may be strengthened whilst farmers may confidently apply pasture management strategies to disrupt the trematode life-cycle. However, accurately identifying and mapping these risk areas is challenging. METHODS: In this study, environmental DNA (eDNA) assays were designed to reveal Galba truncatula, Fasciola hepatica and Calicophoron daubneyi presence within water sources on pasture land. eDNA was captured using a filter-based protocol, with DNA extracted using the DNeasy® PowerSoil® kit and amplified via PCR. In total, 19 potential G. truncatula habitats were analysed on four farms grazed by livestock infected with both F. hepatica and C. daubneyi. RESULTS: Galba truncatula eDNA was identified in 10/10 habitats where the snail was detected by eye. Galba truncatula eDNA was also identified in four further habitats where the snail was not physically detected. Fasciola hepatica and C. daubneyi eDNA was also identified in 5/19 and 8/19 habitats, respectively. CONCLUSIONS: This study demonstrated that eDNA assays have the capabilities of detecting G. truncatula, F. hepatica and C. daubneyi DNA in the environment. Further assay development will be required for a field test capable of identifying and quantifying F. hepatica and C. daubneyi infection risk areas, to support future control strategies. An eDNA test would also be a powerful new tool for epidemiological investigations of parasite infections on farms.


Assuntos
DNA de Helmintos/genética , Fasciola hepatica/isolamento & purificação , Água Doce/parasitologia , Paramphistomatidae/isolamento & purificação , Poaceae/parasitologia , Caramujos/genética , Animais , DNA de Helmintos/isolamento & purificação , Ecossistema , Fasciola hepatica/classificação , Fasciola hepatica/genética , Água Doce/química , Paramphistomatidae/classificação , Paramphistomatidae/genética , Controle de Pragas , Poaceae/química , Caramujos/parasitologia
14.
Trans R Soc Trop Med Hyg ; 112(5): 216-222, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29860359

RESUMO

Background: The aim of the investigation was to determine the risk factors for human fascioliasis in schoolchildren in five localities of the Baños del Inca district in Cajamarca, Peru. Secondarily, the prevalence of infection among this population was also studied. Methods: A questionnaire was applied to 270 schoolchildren from 6-12 years of age and to their parents with the aim of collecting information related to risk factors predisposing the children to Fasciola hepatica infection. Faecal samples from all the children were tested for F. hepatica using the modified rapid sedimentation method of Lumbreras and the technique of Kato-Katz for egg counts. Results: Risk factors were identified as follows-raising cattle, consumption of radishes and chewing grass. The prevalence of F. hepatica in Baños del Inca was 6.30%; there was no significant difference by sex or age. Conclusion: Risk factors associated with this parasitosis in children in this area of Cajamarca were the raising of cattle, the consumption of radish and the habit of chewing grass. The prevalence results in this district suggest a mesoendemic level of infection, with local variations between meso- and hyper-endemic levels.


Assuntos
Doenças dos Bovinos/parasitologia , Fasciola hepatica/isolamento & purificação , Fasciolíase/epidemiologia , Fezes/parasitologia , Instituições Acadêmicas , Estudantes , Criação de Animais Domésticos , Animais , Bovinos , Criança , Fasciolíase/etiologia , Fasciolíase/parasitologia , Feminino , Humanos , Masculino , Peru/epidemiologia , Projetos Piloto , Poaceae/parasitologia , Prevalência , Raphanus/parasitologia , Fatores de Risco , Estudantes/estatística & dados numéricos , Abastecimento de Água
15.
Plant Biol (Stuttg) ; 20(4): 759-764, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29577546

RESUMO

Root-hemiparasitic interaction between the dominant grass Calamagrostis epigejos and the hemiparasite Thesium linophyllon was studied to assess the potential of the parasite to regulate dominance of the grass, which is expanding into species-rich steppe grasslands. First, we aimed to identify physiological links between the two species as a principal indicator of the parasitic relationship. Second, we analysed the dynamics of the two species in the vegetation of a steppe grassland at the foot of the Bükk Mountains, Hungary, where their joint presence is recorded in a long-term permanent plot monitoring dataset to detect patterns associated with the parasitic ecological interaction. Numerous well-developed functional haustoria of Th. linophyllon were identified on the root systems of C. epigejos. The joint dynamics of C. epigejos and Th. linophyllon displayed clear signs of the parasitic interaction: (1) the dynamics of Th. linophyllon frequency was positively associated with the initial cover of C. epigejos; (2) maximum recorded cover values of the two species were strongly positively correlated; and (3) the extent of C. epigejos decrease in the vegetation was significantly positively associated with maximum Th. linophyllon cover recorded throughout the monitoring period. We demonstrate that C. epigejos can be parasitized by Th. linophyllon, which restricts abundance of the grass. Th. linophyllon thus has potential to act as a native biological control of C. epigejos in steppe grasslands.


Assuntos
Interações Hospedeiro-Parasita/fisiologia , Raízes de Plantas/parasitologia , Poaceae/parasitologia , Traqueófitas/fisiologia , Hungria
16.
Vet Parasitol ; 252: 107-116, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29559130

RESUMO

The distribution of gastro-intestinal (GI) parasites across landscapes is closely related to the spatial distribution of hosts. In GI parasites with environmental life stages, the vitality of parasites is also affected by ecological and landscape-related components of the environment. This is particularly relevant for domestic livestock species that are often kept across habitats with varying degrees of degradation, exposing them to a wide range of environmentally robust parasite species. In our study, we examined the effect of environmental and anthropogenic factors on the prevalence and intensity of GI parasites across a free-ranging stock of Ankole cattle in the Mutara rangelands of northeastern Rwanda. Prevalence and intensity of each parasite type (i.e., strongyle-type nematodes, Strongyloides spp., Moniezia spp., and Eimeria spp.) were used as dependent variables. Two fixed factors related to season and conservation-political history, together with three principal components (condensed from nine ecological variables) were used as independent covariates in a univariate General Linear Model (GLM). Major effects on the prevalence and intensity of strongyle-type nematodes and on the intensity of Eimeria spp. were found in that vegetation-related effects such as above-ground grass biomass in conjunction with a high degree of soil compaction had a negative relationship with these parasite types. These unexpected findings suggest that strongyle-type and coccidian infections increase with increasing rangeland degradation. Strongyle-type nematode prevalence and intensity were also negatively related to goat/sheep density, indicating a 'dilution effect' of GI infections between domestic livestock species.


Assuntos
Coccidiose/veterinária , Ecologia , Eimeria/isolamento & purificação , Trato Gastrointestinal/parasitologia , Enteropatias Parasitárias/veterinária , Estrongiloidíase/veterinária , Animais , Biomassa , Bovinos/parasitologia , Coccidiose/parasitologia , Fezes/parasitologia , Cabras/parasitologia , Herbivoria , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Contagem de Ovos de Parasitas/veterinária , Poaceae/parasitologia , Prevalência , Estações do Ano , Solo/química , Solo/parasitologia , Strongyloides/isolamento & purificação , Strongyloides/fisiologia
17.
PLoS One ; 13(2): e0191536, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29489819

RESUMO

Spider mites, a cosmopolitan pest of agricultural and landscape plants, thrive under hot and dry conditions, which could become more frequent and extreme due to climate change. Recent work has shown that neonicotinoids, a widely used class of systemic insecticides that have come under scrutiny for non-target effects, can elevate spider mite populations. Both water-stress and neonicotinoids independently alter plant resistance against herbivores. Yet, the interaction between these two factors on spider mites is unclear, particularly for Banks grass mite (Oligonychus pratensis; BGM). We conducted a field study to examine the effects of water-stress (optimal irrigation = 100% estimated evapotranspiration (ET) replacement, water stress = 25% of the water provided to optimally irrigated plants) and neonicotinoid seed treatments (control, clothianidin, thiamethoxam) on resident mite populations in corn (Zea mays, hybrid KSC7112). Our field study was followed by a manipulative field cage study and a parallel greenhouse study, where we tested the effects of water-stress and neonicotinoids on BGM and plant responses. We found that water-stress and clothianidin consistently increased BGM densities, while thiamethoxam-treated plants only had this effect when plants were mature. Water-stress and BGM herbivory had a greater effect on plant defenses than neonicotinoids alone, and the combination of BGM herbivory with the two abiotic factors increased the concentration of total soluble proteins. These results suggest that spider mite outbreaks by combinations of changes in plant defenses and protein concentration are triggered by water-stress and neonicotinoids, but the severity of the infestations varies depending on the insecticide active ingredient.


Assuntos
Neonicotinoides/farmacologia , Poaceae/parasitologia , Estresse Fisiológico , Tetranychidae/efeitos dos fármacos , Animais , Secas
18.
PLoS One ; 13(2): e0192397, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29415001

RESUMO

Plant-parasitic nematodes of the genus Meloidogyne, known as root-knot nematodes (RKN), have an important economic impact on golf course turfgrasses. The most prevalent RKN species associated with grasses are M. chitwoodi, M. graminicola, M. graminis, M. incognita, M. marylandi, M. microtyla, M. minor, M. naasi and M. sasseri. In 2010, slight thickening of the roots and RKN females with unusual features were observed in turfgrass roots on golf courses in Araras, São Paulo state, Brazil. This population (MgARA) was maintained in the lab and studied including morphological, morphometrical, biochemical and molecular markers. Morphology and morphometry were variable and not useful for identification, although perineal pattern morphology showed highly similarity with M. graminis description. Concerning to biochemical characterisation, the esterase phenotype Mg1, characterised by a very slow and fainter band, was detected in some protein homogenates. Regarding to molecular analysis, D2-D3 region of 28S rDNA gene and cytochrome oxidase subunit II region from mitochondrial DNA were amplified by PCR and sequenced. Phylogenetic analysis revealed that the Brazilian isolate, found associated with turfgrass, grouped with M. graminis isolates (98-99% bootstrap; variation of 8-11 and 0-24 bp, respectively), close to M. marylandi, supporting its identification as M. graminis. This is the first report of M. graminis on golf courses in Brazil.


Assuntos
Poaceae/parasitologia , Tylenchoidea/isolamento & purificação , Animais , Brasil , Tylenchoidea/genética
19.
Res Vet Sci ; 117: 233-238, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29310034

RESUMO

Commencing in 2012, an epidemic of infectious bovine anaemia associated with Theileria orientalis Ikeda type has been present in New Zealand. The aims of this study were to analyse the temporal and spatial effects of T. orientalis Ikeda type infection on the sample submission rates and haematocrits of infected cattle over the first two years of the New Zealand epidemic. The data were collected from 30/08/2012 to 28/11/2014 and included all samples that met the case definition for Theileria associated bovine anaemia (TABA) and tested positive for T. orientalis Ikeda type by PCR. The sample submission rates by month and farm type were highly seasonal with dairy farm submissions peaking in September a month before beef farm submissions peaked. A second lesser peak of dairy farm submissions in April was absent for beef farms. A mixed effects model was fitted to the data and showed a significant interaction between farm production type (dairy or beef) and month of sampling (p=0.006) and between latitude and month of sampling (p=0.024). The estimated haematocrit, adjusted for month and latitude, for dairy cattle=0.125 (95%CI 0.121-0.129) and for beef cattle=0.151 (95% CI 0.138-0.165), p<0.0001. This research shows that infected beef animals tend to be less severely affected than dairy animals and that the month of sampling and latitude of the sampled farm have significant and interacting effects on the level of anaemia associated with T. orientalis Ikeda type infection.


Assuntos
Anemia/veterinária , Doenças dos Bovinos/sangue , Anemia/sangue , Anemia/parasitologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Fazendas , Nova Zelândia , Poaceae/parasitologia , Theileria , Theileriose/sangue
20.
PLoS One ; 13(1): e0191187, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29338057

RESUMO

Larvae of Melanotus cribricollis, feed on bamboo shoots and roots, causing serious damage to bamboo in Southern China. However, there is currently no effective control measure to limit the population of this underground pest. Previously, a new entomopathogenic fungal strain isolated from M. cribricollis larvae cadavers named Metarhizium pingshaense WP08 showed high pathogenic efficacy indoors, indicated that the fungus could be used as a bio-control measure. So far, the genetic backgrounds of both M. cribricollis and M. pingshaense WP08 were blank. Here, we analyzed the whole transcriptome of M. cribricollis larvae, infected with M. pingshaense WP08 or not, using high-throughput next generation sequencing technology. In addition, the transcriptome sequencing of M. pingshaense WP08 was also performed for data separation of those two non-model species. The reliability of the RNA-Seq data was also validated through qRT-PCR experiment. The de novo assembly, functional annotation, sequence comparison of four insect species, and analysis of DEGs, enriched pathways, GO terms and immune related candidate genes were operated. The results indicated that, multiple defense mechanisms of M. cribricollis larvae are initiated to protect against the more serious negative effects caused by fungal infection. To our knowledge, this was the first report of transcriptome analysis of Melanotus spp. infected with a fungus, and it could provide insights to further explore insect-fungi interaction mechanisms.


Assuntos
Besouros/genética , Besouros/microbiologia , Metarhizium/patogenicidade , Animais , Agentes de Controle Biológico , Perfilação da Expressão Gênica , Genes de Insetos , Sequenciamento de Nucleotídeos em Larga Escala , Larva/genética , Larva/microbiologia , Metarhizium/genética , Família Multigênica , Filogenia , Poaceae/parasitologia , Análise de Sequência de RNA
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