850 resultados para Sarcocystis tenella


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O trabalho teve como objetivo avaliar a ação dos herbicidas imazethapyr e chlorimuron-ethyl em aplicações de pré-semeadura da cultura da soja, visando o controle das plantas daninhas presentes antes da semeadura e a redução na emergência de plantas daninhas durante o ciclo da cultura. O experimento foi conduzido a campo, em área de produção de soja em sistema de plantio direto. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetições, em esquema fatorial (4 x 4 + 1), sendo quatro tratamentos herbicidas [glyphosate (1,62 kg ha-1); glyphosate (1,62 kg ha-1) + imazethapyr (100 g ha-1); glyphosate (1,62 kg ha-1) + chlorimuron-ethyl (10 g ha-1); glyphosate (1,62 kg ha-1) + chlorimuron-ethyl (20 g ha-1)] e quatro intervalos entre a aplicação dos herbicidas e a semeadura da soja (0, 1, 3 e 7 dias), mais uma testemunha não-dessecada. A adição dos herbicidas imazethapyr (100 g ha¹) e chlorimuron-ethyl (10 ou 20 g ha-1) junto ao glyphosate não melhorou o controle e também não diminuiu a rebrota posterior das plantas daninhas Digitaria insularis, Tridax procumbens e Leptochloa filiformis. Três dias antes da semeadura da soja foi o intervalo mínimo para que o controle dessas três espécies de plantas daninhas não fosse prejudicado pela operação de semeadura mecânica. Constatou-se que os tratamentos herbicidas não afetaram o número de plantas emergidas das espécies Sida santaremnensis, Digitaria insularis, Eleusine indica, Chamaesyce hirta, Bidens pilosa e Senna obtusifolia. Apenas para a espécie Althernantela tenella foi verificado que a adição de imazethapyr ou de chlorimuron-ethyl junto ao glyphosate reduziu a emergência dessa planta daninha na área, mostrando eficiência em pré-emergência. Todos os tratamentos herbicidas aplicados em pré-semeadura proporcionaram maior produtividade da cultura da soja em relação à testemunha não-dessecada, mas o incremento dos herbicidas imazethapyr e chlorimuron-ethyl ao glyphosate não resultou em aumento de produtividade da soja.

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Com o objetivo de avaliar o efeito residual de flumioxazin sobre a emergência de plantas daninhas em solos de texturas distintas, foi realizado um experimento em casa de vegetação. Os tratamentos foram constituídos pela combinação de quatro épocas de aplicação: 14, 10, 7 e 0 dias antes da semeadura das espécies de plantas daninhas, com duas doses de flumioxazin (25 e 40 g ha-1) e uma testemunha sem aplicação para cada planta daninha em solos de texturas distintas. O efeito residual do herbicida flumioxazin foi avaliado por meio da contagem do número de plantas emersas de cada espécie aos 35 dias depois da semeadura (DDS). O controle do fluxo inicial de emergência de plantas daninhas variou em função do tipo de solo, do período de tempo entre a aplicação e a semeadura das espécies e também da dose. A. tenella, D. horizontalis, D. insularis, D. tortuosum, E. heterophylla, N. physaloides e S. latifolia foram as espécies mais sensíveis à aplicação de flumioxazin (25 e 40 g ha-1).

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Multivariate morphometrics and image analysis were used to determine the number of well-distinguished infrageneric taxa of reddish freshwater Audouinella in North America. Three distinct groupings were differentiated from 83 populations collected from Alaska and Labrador in the north to central Mexico and Jamaica in the south. These groupings were statistically related to seven type specimens. The following species were recognized: A. eugenea (SKUJA) JAO, A. hermannii (ROTH) DUBY [syn.: A. violacea (KUTZ.) HAMEL and its varieties, alpina (KUTZ.) RAB., dalmatica (KUTZ.) RAB., expansa (WOOD) SMITH, and hercynica (KUTZ.) KUTZ.] and A. tenella (SKUJA) PAPENFUSS. These species are separated based on dimensions of vegetative cells and monosporangia. A. tenella is found only in California, A. eugenea in warm, alkaline and high-ion waters of the tropical rainforest and desert-chaparral, while A. hermannii occurs widely from the boreal to south temperate and in waters with relatively low temperatures and ion content.

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Indirect ELISA and IFAT have been reported to be more sensitive and specific than agglutination tests. However, MAT is cheaper, easier than the others and does not need special equipment. The purpose of this study was to compare an enzyme linked immunosorbent assay using crude rhoptries of Toxoplasma gondii as coating wells (r-ELISA) with indirect fluorescence antibody test (IFAT) and modified agglutination test (MAT) to detect anti-T. gondii antibodies in sera of experimentally infected pigs. Ten mixed breed pigs between 6.5 and 7.5 weeks old were used. All pigs were negative for the presence of T. gondii antibodies by IFAT (titre < 16), r-ELISA (OD < 0.295) and MAT (titre < 16). Animals received 7 × 107 viable tachyzoites of the RH strain by intramuscular (IM) route at day 0. Serum samples were collected at days -6, 0, 7, 14, 21, 28, 35, 42, 50, and 57. IFAT detected anti-T. gondii antibodies earlier than r-ELISA and MAT. The average of antibody levels was higher at day 35 in IFAT (Log10 = 2.9) and in MAT (Log10 = 3.5), and at day 42 in r-ELISA (OD = 0.797). The antibody levels remained high through the 57th day after inoculation in MAT, and there was a decrease tendency in r-ELISA and IFAT. IFAT was used as gold standard and r-ELISA demonstrated a higher prevalence (73.3%), sensitivity (94.3%), negative predictive value (83.3%), and accuracy (95.6%) than MAT. Kappa agreements among tests were calculated, and the best results were shown by r-ELISA × IFAT (κ = 0.88, p < 0.001). Cross-reaction with Sarcocystis miescheriana was investigated in r-ELISA and OD mean was 0.163 ± 0.035 (n = 65). Additionally, none of the animals inoculated with Sarcocystis reacted positively in r-ELISA. Our results indicate that r-ELISA could be a good method for serological detection of T. gondii infection in pigs. © 2005 Elsevier Inc. All rights reserved.

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In this article, seven Bdellidae Dugès (Acari: Trombidiformes) of the Museum of Comparative Zoology, originally described by Nathan Banks are studied: Cyta americana (Banks, 1902), Bdella tenella Banks, 1896, Bdella utilis Banks, 1914, Bdella californica Banks, 1904, Bdella cardinalis Banks, 1894, Bdella peregrina Banks, 1894 and Bdella brevitarsis Banks. Bdella tenella and Bdella californica are transferred to the genera Spinibdella and Bdellodes, respectively. Bdella brevitarsis, previously a nomen nudum, is herein described for the first time under the genus Hexabdella. http://zoobank.org/urn:lsid: zoobank.org:pub:A18C8C10-8C8A-4873-AF0B-D1A9164CD7E8 © 2013 Copyright 2013 Taylor & Francis.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Pós-graduação em Medicina Veterinária - FMVZ

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Forty-five Brazilian populations of freshwater Audouinella were analysed using multivariate morphometrics. These populations were statistically related to seven type specimens. Five species are recognised on the basis of qualitative (plant colour and size, basal system type and branch angle) and quantitative (length and diameter of vegetative cells and monosporangia) characters. A. hermannii (syn. A. violacea) is characterised by a reddish colour, an irregular prostrate basal system, open branch angles (greater than or equal to 25 degrees) and small monosporangia (less than or equal to 15 mu m in diameter). A. macrospora (syn. A. chalybea var. brasiliensis) is distinguished from the other Brazilian species by having a bluish colour, a basal system composed of well-developed rhizoids, narrow branch angles (< 25 degrees) and large monosporangia (greater than or equal to 15 mu m in diameter). A. meiospora is microscopic and has a reddish colour, a basal system composed of creeping filaments, narrow branch angles and small monosporangia. A. pysmaea (syn. A. leibleinii) is characterised by being bluish, having an irregular prostrate basal system, narrow branch angles and small monosporangia. A, tenella is distinct from the other species by having a reddish colour, an irregular prostrate basal system, open branch angles, small monosporangia and small vegetative cells (less than or equal to 6 mu m in diameter). An identification key and revised descriptions and synonyms are presented for the five species. A. meiospora and A. tenella are reported for the first time for Brazil. A. macrospora and A. pygmaea were the most widespread species and occurred in tropical and subtropical regions. A. meiospora was found at two sites in a tropical rainforest region, whereas A. hermannii and A. tenella were found at only one site. Selected physical and chemical environmental data (temperature, specific conductance, current velocity, turbidity, pH and dissolved oxygen) are presented for most species.

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Pós-graduação em Ciência e Tecnologia Animal - FEIS

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• Chronic Wasting Disease Update: Wisconsin, Minnesota, South Dakota, Colorado; National CWD Management – USDA & USDI National Plan for Assisting States, Federal Agencies, and Tribes in Managing Chronic Wasting Disease in Free-ranging and Captive Cervids • West Nile virus (WNV) reaches the Pacific coast • West Nile Virus in Blue Jays • Idaho Brucellosis Linked to Wildlife: All of the epidemiological and laboratory information clearly indicates that brucellosis-infected elk transmitted the disease to the cattle herd. • Tularemia caused a die-off of captured wild prairie dogs this summer at a Texas commercial exotic animal facility that distributes the animals for sale as pets. • Raptors can acquire avian vacuolar myelinopathy (AVM) via ingestion of other affected birds. • House Finch Mycoplasmosis: bacterial eye disease of house finches • Raccoon Rabies report • Toxoplasmosis – The newest finding regarding sea otters in California is the importance of toxoplasmosis as a mortality factor. Toxoplasma gondii is a protozoan parasite that can invade visceral organs and the central nervous system to cause acute, disseminated tissue necrosis and fatal meningoencephalitis in susceptible animals. In recent years, 36% of dead sea otters examined have been infected. Another tissue-invading protozoan, Sarcocystis neurona, also was found in 4% of the otters. • Recovery of remnant populations of the endangered black-footed ferret have been hampered by sylvatic plague, which is caused by the bacterium Yersinia pestis. • Dr. Samantha Gibbs received the Wildlife Disease Association’s Student Research Recognition Award. Dr. Cynthia Tate was selected by the American Association of Veterinary Parasitologists to receive the Best Student Presentation Award. Dr. Andrea Varela won second place in the Student Presentation Award for her presentation at the meeting of the American Association Veterinary Parasitologists. Mr. Michael Yabsley received the Wildlife Disease Association Student Scholarship and the S.A. Ewing Vectorborne Parasitology Award from the University of Georgia’s College of Veterinary Medicine.

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Huanglongbing (HLB) is a severe citrus (Citrus spp.) disease associated with the bacteria genus Candidatus Liberibacter, detected in Brazil in 2004. Another bacterium was found in association with HLB symptoms and characterized as a phytoplasma belonging to the 16SrIX group. The objectives of this study were to identify potential leafhopper vectors of the HLB-associated phytoplasma and their host plants. Leafhoppers were sampled every other week for 12 mo with sticky yellow cards placed at two heights (0.3 and 1.5 m) in the citrus tree canopy and by using a sweep net in the ground vegetation of two sweet orange, Citrus sinensis (L.) Osbeck, groves infected by the HLB-phytoplasma in Sao Paulo state. Faunistic analyses indicated one Agalliinae (Agallia albidula Uhler) and three Deltocephalinae [Balclutha hebe (Kirkaldy), Planicephalus flavicosta (Stal), and Scaphytopius (Convelinus) marginelineatus (Stal)] species, as the most abundant and frequent leafhoppers (Hemiptera: Cicadellidae). Visual observations indicated an association of leafhopper species with some weeds and the influence of weed species composition on leafhopper abundance in low-lying vegetation. S. marginelineatus and P. flavicosta were more frequent on Sida rhombifolia L. and Althernantera tenella Colla, respectively, whereas A. albidula was observed more often on Conyza bonariensis (L.) Cronq. and B. hebe only occurred on grasses. DNA samples of field-collected S. marginelineatus were positive by polymerase chain reaction and sequencing tests for the presence of the HLB-phytoplasma group, indicating it as a potential vector. The association of leafhoppers with their hosts may be used in deciding which management strategies to adopt against weeds and diseases in citrus orchards.

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Coccidiosis of the domestic fowl is a worldwide disease caused by seven species of protozoan parasites of the genus Eimeria. The genome of the model species, Eimeria tenella, presents a complexity of 55-60 MB distributed in 14 chromosomes. Relatively few studies have been undertaken to unravel the complexity of the transcriptome of Eimeria parasites. We report here the generation of more than 45,000 open reading frame expressed sequence tag (ORESTES) cDNA reads of E. tenella, Eimeria maxima and Eimeria acervulina, covering several developmental stages: unsporulated oocysts, sporoblastic oocysts, sporulated oocysts, sporozoites and second generation merozoites. All reads were assembled to constitute gene indices and submitted to a comprehensive functional annotation pipeline. In the case of E. tenella, we also incorporated publicly available ESTs to generate an integrated body of information. Orthology analyses have identified genes conserved across different apicomplexan parasites, as well as genes restricted to the genus Eimeria. Digital expression profiles obtained from ORESTES/EST countings, submitted to clustering analyses, revealed a high conservation pattern across the three Eimeria spp. Distance trees showed that unsporulated and sporoblastic oocysts constitute a distinct clade in all species, with sporulated oocysts forming a more external branch. This latter stage also shows a close relationship with sporozoites, whereas first and second generation merozoites are more closely related to each other than to sporozoites. The profiles were unambiguously associated with the distinct developmental stages and strongly correlated with the order of the stages in the parasite life cycle. Finally, we present The Eimeria Transcript Database (http://www.coccidia.icb.usp.br/eimeriatdb), a website that provides open access to all sequencing data, annotation and comparative analysis. We expect this repository to represent a useful resource to the Eimeria scientific community, helping to define potential candidates for the development of new strategies to control coccidiosis of the domestic fowl. (C) 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.