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Sample records for boophilus microplus al

  1. Primer caso de resistencia al amitraz en la garrapata del ganado Boophilus microplus en México

    OpenAIRE

    Noé Soberanes Céspedes; Minerva Santamaría Vargas; Hugo Fragoso Sánchez; Zeferino García Vázquez

    2002-01-01

    El objetivo de este estudio fue documentar el primer caso de la resistencia de la garrapata B. microplus al Amitraz, en México. Se obtuvo una muestra de garrapatas B. microplus del municipio de Emiliano Zapata, Tabasco, con reportes de fallas de control con este acaricida. La cepa de garrapatas fue denominada “San Alfonso” y se utilizaron larvas (F1) provenientes de la generación parental de hembras repletas, éstas se probaron con dosis discriminate de Amitraz 0.0002 %, (Taktic®) en formulaci...

  2. An Overview of the Status of Cattle Tick Boophilus microplus in Queensland

    OpenAIRE

    Davis, Rex

    1996-01-01

    The common cattle tick Boophilus microplus has been a major economic pest to cattle producers in the tick-infested area of Queensland since its arrival from Java in 1872. Boophilus microplus affects cattle directly by reducing potential yield and indirectly through the transmission of blood parasites. Estimates by the Cattle Tick Commission (1973) placed the total cost of control and lost production caused by Boophilus microplus at approximately $33 million per annum (approximately $183 milli...

  3. Resistencia de la garrapata Boophilus microplus a los ixodicidas

    OpenAIRE

    M. A. Alonso-Díaz; R I Rodríguez-Vivas; H Fragoso-Sánchez; R Rosario-Cruz

    2006-01-01

    La resistencia de las garrapatas a los ixodicidas es uno de los principales problemas que afectan a los productores bovinos en el subtrópico y trópico, donde las garrapatas, especialmente Boophilus microplus y los agentes que transmiten, tienen un efecto costo-beneficio en la producción. El objetivo de la presente revisión es dar a conocer los principales hallazgos de la resistencia de B. microplus. Se presenta la definición, desarrollo, evolución y el diagnóstico de la resistencia. Asimismo,...

  4. Resistencia de la garrapata Boophilus microplus a los ixodicidas Ixodicide resistance of the the Boophilus microplus tick to ixodicides

    OpenAIRE

    M. A. Alonso-Díaz; R I Rodríguez-Vivas; H Fragoso-Sánchez; R Rosario-Cruz

    2006-01-01

    La resistencia de las garrapatas a los ixodicidas es uno de los principales problemas que afectan a los productores bovinos en el subtrópico y trópico, donde las garrapatas, especialmente Boophilus microplus y los agentes que transmiten, tienen un efecto costo-beneficio en la producción. El objetivo de la presente revisión es dar a conocer los principales hallazgos de la resistencia de B. microplus. Se presenta la definición, desarrollo, evolución y el diagnóstico de la resistencia. Asimismo,...

  5. Susceptibility of Boophilus microplus (Canestrini, 1887 (Acari: Ixodidae to seven ixodicides in Nuevo Leon, Mexico

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    Jesús A. Esparza Rentería

    2015-07-01

    Full Text Available This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation by the FAUANL for its use Animal husbandry and meat industry in Mexico are one of the principal activities of the agricultural sector of the country, which are threatened by factors that affect the production of meat, skin and milk; among these, the damages caused by Boophilus microplus (Canestrini, the common tick of cattle, and the diseases it transmits, such as anaplasmosis and babesiosis (Xianxun and Wenshun, 1997; Yeruhan et al., 1998, are of special interest. The objective of this study was to determine the susceptibility of the larvae of Boophilus microplus to seven tick-killing agents commonly used in the state of Nuevo Leon. The methodology used for the diagnosis of the susceptibility of B. microplus tick to Organochlorine, Organophosphorate and Pyrethroid compounds was the one applied by Rodriguez-Vivas et al., (2007; in which it was used a discriminant dose (table 1, using the larvae package test technique (Stone & Haydock, 1962. The results of the CL50 to the ticks of cattle in the state of Nuevo Leon, Mexico showed a greater susceptibility to Deltamethrine, followed by Chlorfenvinphos; in third place Diazinon, then Flumethrin; after that Cypermethrin, in sixth place Lindane and a less toxicological action for the Coumaphos (Asuntol. The result was already expected due to the fact that it is the most commonly used product in the control of ticks through the larval immersion technique.

  6. Resistencia de la garrapata Boophilus microplus a los ixodicidas Ixodicide resistance of the the Boophilus microplus tick to ixodicides

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    M A Alonso-Díaz

    2006-01-01

    Full Text Available La resistencia de las garrapatas a los ixodicidas es uno de los principales problemas que afectan a los productores bovinos en el subtrópico y trópico, donde las garrapatas, especialmente Boophilus microplus y los agentes que transmiten, tienen un efecto costo-beneficio en la producción. El objetivo de la presente revisión es dar a conocer los principales hallazgos de la resistencia de B. microplus. Se presenta la definición, desarrollo, evolución y el diagnóstico de la resistencia. Asimismo, se presenta la distribución mundial de la resistencia de las garrapatas, especialmente en México. Se concluye que la resistencia de las garrapatas a los ixodicidas es un problema importante en la producción bovina y se necesitan implementar medidas estratégicas para reducir o retardar el impacto en la ganadería bovina.The tick is a major problem for cattle producers in subtropical and tropical areas where ticks, especially Boophilus microplus, and the disease agents that they transmit, are a constraint to cost-effective production. The aim of the present review is to present the most important findings of acaricide resistance in the B. microplus tick. The definition, development, evolution and diagnosis of tick resistance are presented. The distribution of tick resistance in the world, especially in Mexico is also presented. It is concluded that tick resistance is an important problem for cattle production and strategies need to be developed to reduce the impact on cattle.

  7. Commercialisation of a recombinant vaccine against Boophilus microplus.

    Science.gov (United States)

    Willadsen, P; Bird, P; Cobon, G S; Hungerford, J

    1995-01-01

    Increasingly, there is need for methods to control cattle tick (Boophilus microplus) infestations by the use of non-chemical technology. This need is brought about by a mixture of market forces and the failure or inadequacy of existing technology. A recombinant vaccine has now been developed against the tick. This vaccine relies on the uptake with the blood meal of antibody directed against a critical protein in the tick gut. The isolation of the vaccine antigen, Bm86, and its production as a recombinant protein is briefly described. The vaccine has been tested in the field, has been taken through the full registration process and is now in commercial use in Australia. A related development has occurred in Cuba. The potential for improvement of the current vaccine and for the development of similar vaccines against other haematophagous parasites is discussed. PMID:7784128

  8. Assessment of bacterial diversity in the cattle tick Rhipicephalus (Boophilus) microplus through tag-encoded pyrosequencing

    OpenAIRE

    Bendele Kylie G; Guerrero Felix D; Dowd Scot E; Pérez de León Adalberto A; Andreotti Renato; Scoles Glen A

    2011-01-01

    Abstract Background Ticks are regarded as the most relevant vectors of disease-causing pathogens in domestic and wild animals. The cattle tick, Rhipicephalus (Boophilus) microplus, hinders livestock production in tropical and subtropical parts of the world where it is endemic. Tick microbiomes remain largely unexplored. The objective of this study was to explore the R. microplus microbiome by applying the bacterial 16S tag-encoded FLX-titanium amplicon pyrosequencing (bTEFAP) technique to cha...

  9. Acaricide resistance mechanisms in Rhipicephalus (Boophilus microplus Mecanismos de resistência aos acaricidas em Rhipicephalus (Boophilus microplus

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    Felix David Guerrero

    2012-03-01

    Full Text Available Acaricide resistance has become widespread in countries where cattle ticks, Rhipicephalus (Boophilus microplus, are a problem. Resistance arises through genetic changes in a cattle tick population that causes modifications to the target site, increased metabolism or sequestration of the acaricide, or reduced ability of the acaricide to penetrate through the outer protective layers of the tick’s body. We review the molecular and biochemical mechanisms of acaricide resistance that have been shown to be functional in R. (B. microplus. From a mechanistic point of view, resistance to pyrethroids has been characterized to a greater degree than any other acaricide class. Although a great deal of research has gone into discovery of the mechanisms that cause organophosphate resistance, very little is defined at the molecular level and organophosphate resistance seems to be maintained through a complex and multifactorial process. The resistance mechanisms for other acaricides are less well understood. The target sites of fipronil and the macrocyclic lactones are known and resistance mechanism studies are in the early stages. The target site of amitraz has not been definitively identified and this is hampering mechanistic studies on this acaricide.A resistência aos acaricidas tornou-se amplamente difundida nos países onde os carrapatos bovinos, Rhipicephalus .Boophilus. microplus, são um problema. A resistência surge por meio de alterações genéticas em umapopulação de carrapatos que causam modificações no local de ação, aumento do metabolismo ou sequestro do acaricida, ou ainda redução na capacidade do acaricida em penetrar através das camadas protetoras do corpo do carrapato. Neste artigo, foram revisados os mecanismos moleculares e bioquímicos da resistência aos acaricidas que ocorrem em R. (B. microplus. A partir de um ponto de vista dos mecanismos envolvidos, a resistência aos piretróides tem sido caracterizada em maior grau do

  10. Targeted silencing of the aquaporin 2 gene of rhipicephalus (Boophilus) microplus reduces tick fitness

    Science.gov (United States)

    Ticks are blood-feeding arthropods that can affect human and animal health both directly by up taking blood and indirectly by transmitting pathogens. The cattle tick Rhipicephalus (Boophilus) microplus is one of the most economically important ectoparasites of bovines and it is responsible for the t...

  11. Control de garrapatas Riphicephalus (Boophilus microplus en bovinos con el inmunógeno Herber biogar - Control of Riphicephalus (Boophilus microplus ticks in bovine with the Herber biogar inmunógeno

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    Botello A.R.

    2011-05-01

    Full Text Available ResumenLa presente investigación se realizó con el objetivo de controlar la garrapata Riphicephalus (Boophilus microplus por medio del inmunógeno Herber biogar en bovinos en el municipio de Guanare, Portuguesa, Venezuela.SummaryThis research was conducted with the aim of controlling the tickRiphicephalus (Boophilus microplus through Herber biogar immunogen incattle in the town of Guanare, Portuguesa, Venezuela.

  12. Control de garrapatas Riphicephalus (Boophilus) microplus en bovinos con el inmunógeno Herber biogar - Control of Riphicephalus (Boophilus) microplus ticks in bovine with the Herber biogar inmunógeno

    OpenAIRE

    Botello A.R.; Botello A.L.; Fajardo H.; Pérez Kirenia C.; Gómez I.A.; Borroto C.N.; Marisela Suárez; Pérez Dunia A.; Linares Belkis R.; Colicchia Maribel R.; Peraza Paula S.; Rodríguez Y.V.; González A.O.; Rodríguez A.N.; Gort A.M.

    2011-01-01

    ResumenLa presente investigación se realizó con el objetivo de controlar la garrapata Riphicephalus (Boophilus) microplus por medio del inmunógeno Herber biogar en bovinos en el municipio de Guanare, Portuguesa, Venezuela.SummaryThis research was conducted with the aim of controlling the tickRiphicephalus (Boophilus) microplus through Herber biogar immunogen incattle in the town of Guanare, Portuguesa, Venezuela.

  13. Identificación de un polimorfismo del gen Est9 relacionado con resistencia a piretroides en Rhipicephalus (Boophilus) microplus

    OpenAIRE

    Edgar Diaz R.; Gustavo Vallejo

    2013-01-01

    RESUMENObjetivo. Mediante procedimientos de PCR-RFLP, detectar un polimorfismo en el gen Est9 de garrapatas Rhipicephalus (Boophilus) microplus resistentes a piretroides en Ibagué, Colombia, determinando el grado de asociación entre los fenotipos y los genotipos resultantes. Materiales y métodos. El ADN de 30 teleoginas R. (Boophilus) microplus fenotípicamente susceptibles, resistentes o medianamente resistentes a piretroides en una prueba de Drummond modificada, fue amplificado por PCR con c...

  14. Bovine immunoprotection against Rhipicephalus (Boophilus) microplus with recombinant Bm86-Campo Grande antigen Imunoproteção de bovinos contra Rhipicephalus (Boophilus) microplus com antígeno recombinante Bm86-Campo Grande

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    Rodrigo Casquero Cunha; Adalberto Angel Pérez de León; Fábio Pereira Leivas Leite; Luciano da Silva Pinto; Alceu Gonçalves dos Santos Júnior; Renato Andreotti

    2012-01-01

    The southern cattle fever tick, Rhipicephalus (Boophilus) microplus, is no doubt the most economically important ectoparasite of cattle globally. The inappropriate use of chemical acaricides has driven the evolution of resistance in populations of R. (B.) microplus. Anti-tick vaccines represent a technology that can be combined with acaricides in integrated control programs to mitigate the impact of R. (B.) microplus. The recombinant form of Bm86 antigen from the Campo Grande (rBm86-CG) strai...

  15. A Novel Carbamate Insecticide with Superior Selectivity for Cattle Tick (Boophilus microplus) and Sand Fly (Phlebotomus papatasi) Control

    Science.gov (United States)

    The cattle tick, Boophilus microplus, and the sand fly, Phlebotomus papatasi (Pp), are vectors of infectious agents affecting cattle and humans, respectively. The purpose of this study was to characterize the inhibitor profile of acetylcholinesterases from R. microplus(BmAChE1) and Pp (PpAchE) for c...

  16. Prevalencia de lecherías con Boophilus microplus resistentes a piretroides y factores de riesgo asociados a su presencia en el Departamento de Santa Cruz, Bolivia

    OpenAIRE

    Marbel Villarroel-Alvarez; Roger Iván Rodríguez-Vivas; Fidel Villegas-Anze; Hugo Fragoso-Sánchez; Alejandrina Ortiz-Nájera; Salvador Neri-Orantes

    2006-01-01

    Se realizó un estudio de sección cruzada para determinar la prevalencia de ranchos con garrapatas Boophilus microplus resistentes a piretroides sintéticos (PS), así como posibles factores de riesgo en la Zona Integrada del Departamento de Santa Cruz, Bolivia. Se muestrearon 83 ranchos, donde se colectaron al menos 10 teleoginas de B. microplus para evaluar en su progenie la respuesta a los PS. Se utilizó la prueba de paquete de larvas, con la dosis discriminante para diagnosticar resistencia ...

  17. New approaches toward anti-Rhipicephalus (Boophilus microplus tick vaccine Novas estratégias para o desenvolvimento de uma vacina contra o carrapato Rhipicephalus (Boophilus microplus

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    Luís Fernando Parizi

    2009-03-01

    Full Text Available The tick Rhipicephalus (Boophilus microplus (formerly Boophilus microplus is the major ectoparasite affecting livestock in America, Asia, Africa, and Oceania. Conventional tick control is based on the use of acaricides but immunization of bovines with tick gut proteins induces only a partial protective immune response. Based on this information, distinct research groups have explored the possibility of protecting the animals by inducing an immune response against other tick proteins. However, the antigens so far described do not induce the necessary protection for suppressing the use of acaricides. Currently, several groups are engaged in identifying new tick proteins to be used as targets for the development of new vaccines. This approach focuses on the enhancement of the immunogenicity of antigens already tested by incorporating new adjuvants or formulations and by searching for new antigens. This paper reviews the work done by Brazilian researchers to develop a vaccine against this tick.O carrapato Rhipicephalus (Boophilus microplus (anteriormente Boophilus microplus é o principal ectoparasita que afeta bovinos na América, Ásia, África e Oceania e o seu controle é tradicionalmente realizado através do uso de acaricidas. Experimentos de imunização com proteínas do carrapato mostram que a resposta imune desenvolvida pelos bovinos vacinados protege, em parte, os animais do parasitismo. Baseado nessas observações, vários grupos de pesquisa exploram a possibilidade de proteger os animais pela indução de uma resposta imune contra proteínas do carrapato. Entretanto, os antígenos já caracterizados não asseguram o grau de proteção necessário para suprimir o uso de acaricidas. Portanto, esses grupos de pesquisa estão engajados na tentativa de identificar novas proteínas que possam ser utilizadas para o desenvolvimento de novas vacinas, as quais possam induzir maior imunogenicidade de que os antígenos já testados, através do

  18. Boophiline, an Antimicrobial Sterol Amide from the Cattle Tick Boophilus microplus

    OpenAIRE

    Potterat, Olivier; Hostettmann, Kurt; Höltzel, Alexandra; Jung, Günther; Diehl, Peter A.; Petrini, Orlando

    2008-01-01

    Boophiline (1), a new sterol amide was isolated from the cattle tick Boophilus microplus (Ixodidae). The structure was assigned as N-[3-(sulfooxy)-25ξ-cholest-5-en-26-oyl]-L-isoleucine by detailed 2D NMR investigations in conjunction with FAB mass spectrometry and acidic hydrolyses. Complete assignment of the diastereotopic methylene protons of the ring system could be deduced from the NMR data. In agar dilution assays, 1 exhibited antifungal properties against Cladosporium cucumerinum and an...

  19. In vitro effects of Pilocarpus microphyllus extracts and pilocarpine hydrochloride on Rhipicephalus (Boophilus) microplus

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    Karina Neoob de Carvalho Castro; David Fernandes Lima; Dolores Wolschick; Ivanilza Moreira de Andrade; Raimunda Cardoso dos Santos; Francisco José de Seixas dos Santos; Leiz Maria Costa Veras; Lívio Martins Costa-Júnior

    2016-01-01

    Abstract The aim of this study was to assess the activity of aqueous (AE) and ethanolic extracts (EE) and pilocarpine hydrochloride, which were extracted and isolated from Pilocarpus microphyllus (Jaborandi), respectively, on Rhipicephalus (Boophilus) microplus. High performance liquid chromatography (HPLC) was performed to quantify these compounds. Larval packet and adult immersion tests were conducted with different concentrations. Five AE and EE concentrations, ranging from 6.2 to 100.0 mg...

  20. Susceptibility of Boophilus microplus (Canestrini, 1887) (Acari: Ixodidae) to seven ixodicides in Nuevo Leon, Mexico

    OpenAIRE

    Jesús A. Esparza Rentería; Emily Lizett Esparza Sevilla

    2015-01-01

    This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation by the FAUANL for its use Animal husbandry and meat industry in Mexico are one of the principal activities of the agricultural sector of the country, which are threatened by factors that affect the production of meat, skin and milk; among these, the damages caused by Boophilus microplus (Canestrini), the common tick of cattle, and the diseases it transm...

  1. Rhipicephalus (Boophilus) microplus resistant to acaricides and ivermectin in cattle farms of Mexico.

    Science.gov (United States)

    Rodríguez-Vivas, Róger Iván; Pérez-Cogollo, Luis Carlos; Rosado-Aguilar, José Alberto; Ojeda-Chi, Melina Maribel; Trinidad-Martinez, Iris; Miller, Robert John; Li, Andrew Yongsheng; de León, Adalberto Pérez; Guerrero, Félix; Klafke, Guilherme

    2014-01-01

    Ticks and the diseases they transmit cause great economic losses to livestock in tropical countries. Non-chemical control alternatives include the use of resistant cattle breeds, biological control and vaccines. However, the most widely used method is the application of different chemical classes of acaricides and macrocyclic lactones. Populations of the cattle tick, Rhipicephalus (Boophilus) microplus, resistant to organophosphates (OP), synthetic pyrethroids (SP), amitraz and fipronil have been reported in Mexico. Macrocyclic lactones are the most sold antiparasitic drug in the Mexican veterinary market. Ivermectin-resistant populations of R. (B.) microplus have been reported in Brazil, Uruguay and especially in Mexico (Veracruz and Yucatan). Although ivermectin resistance levels in R. (B.) microplus from Mexico were generally low in most cases, some field populations of R. (B.) microplus exhibited high levels of ivermectin resistance. The CHPAT population showed a resistance ratio of 10.23 and 79.6 at lethal concentration of 50% and 99%, respectively. Many field populations of R. (B.) microplus are resistant to multiple classes of antiparasitic drugs, including organophosphates (chlorpyrifos, coumaphos and diazinon), pyrethroids (flumethrin, deltamethrin and cypermethrin), amitraz and ivermectin. This paper reports the current status of the resistance of R. (B.) microplus to acaricides, especially ivermectin, in Mexican cattle. PMID:25054487

  2. Bovine immunoprotection against Rhipicephalus (Boophilus) microplus with recombinant Bm86-Campo Grande antigen.

    Science.gov (United States)

    Cunha, Rodrigo Casquero; Pérez de León, Adalberto Angel; Leite, Fábio Pereira Leivas; Pinto, Luciano da Silva; Dos Santos Júnior, Alceu Gonçalves; Andreotti, Renato

    2012-01-01

    The southern cattle fever tick, Rhipicephalus (Boophilus) microplus, is no doubt the most economically important ectoparasite of cattle globally. The inappropriate use of chemical acaricides has driven the evolution of resistance in populations of R. (B.) microplus. Anti-tick vaccines represent a technology that can be combined with acaricides in integrated control programs to mitigate the impact of R. (B.) microplus. The recombinant form of Bm86 antigen from the Campo Grande (rBm86-CG) strain of R. (B.) microplus was produced using the Pichiapastoris expression system to test its ability to immunoprotect cattle against tick infestation. Secretion of rBm86-CG by P. pastoris through the bioprocess reported here simplified purification of the antigen. A specific humoral immune response was detected by ELISA in vaccinated cattle. Immunoblot results revealed that polyclonal antibodies from vaccinated cattle recognized a protein in larval extracts with a molecular weight corresponding to Bm86. The rBm86-CG antigen showed 31% efficacy against the Campo Grande strain of R. (B.) microplus infesting vaccinated cattle. The rBm86-CG is an antigen that could be used in a polyvalent vaccine as part of an integrated program for the control of R. (B.) microplus in the region that includes Mato Grosso do Sul. PMID:23070436

  3. Esterase mediated resistance in deltamethrin resistant reference tick colony of Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Gupta, Snehil; Ajith Kumar, K G; Sharma, Anil Kumar; Nagar, Gaurav; Kumar, Sachin; Saravanan, B C; Ravikumar, Gandham; Ghosh, Srikant

    2016-06-01

    Monitoring of acaricide resistance is considered as one of the important facets of integrated tick management. In an attempt of development of resistance monitoring indicators, in the present study two reference tick lines of Rhipicephalus (Boophilus) microplus maintained in the Entomology laboratory, Indian Veterinary Research Institute (IVRI), Izatnagar, India, were studied to determine the possible contributing factors involved in development of resistance to deltamethrin. Electrophoretic profiling of esterase enzymes detected high activities of EST-1 in reference resistant tick colony designated as IVRI-IV whereas it was not detectable in reference susceptible IVRI-I line of R. (B.) microplus. Esterases were further characterized as carboxylesterase or acetylcholinesterase based on inhibitor study using PMSF, eserine sulphate, malathion, TPP and copper sulphate. It was concluded that an acetylcholinesterase, EST-1, possibly plays an important role for development of deltamethrin resistance in IVRI-IV colony of R. (B.) microplus. PMID:26979585

  4. Larvicidal potential of Sapindus saponaria to control the cattle tick Boophilus microplus Potencial larvicida de Sapindus saponaria para controle do carrapato bovino Boophilus microplus

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    Fernando de Freitas Fernandes

    2005-12-01

    Full Text Available The objective of this study was to evaluate the larvicidal potential of a crude ethanol extract (CEE of soapberry Sapindus saponaria stem peel on the cattle tick Boophilus microplus. Tick larvae obtained by incubating engorged females, collected from naturally infested cattle, were placed in envelopes of filter paper impregnated with different concentrations of CEE in the test group, and distilled water in the control group. Four repetitions were made with each solution (n>120. Mortality was observed after 48 hours. Lethal concentration values of 1,258 ppm (LC50 and 6,360 ppm (LC99 were obtained.Este trabalho objetivou avaliar o potencial larvicida do extrato bruto etanólico (EBE, da casca do caule de Sapindus saponaria, sobre Boophilus microplus. Larvas desse carrapato foram obtidas pela incubação de teleóginas, coletadas de bovinos naturalmente infestados. As larvas foram acondicionadas em envelopes de papel-filtro, impregnados com diferentes concentrações do EBE no grupo teste, e com água destilada no grupo controle. Quatro repetições foram feitas com cada solução (n>120. A mortalidade foi observada após 48 horas. Foram obtidas concentrações letais CL50 de 1.258 ppm e CL99 de 6.360 ppm.

  5. Immunological control of ticks through vaccination with Boophilus microplus gut antigens.

    Science.gov (United States)

    De La Fuente, J; Rodríguez, M; García-García, J C

    2000-01-01

    The control of tick infestations and the transmission of tick-borne diseases remain a challenge for the scientific community. Traditional control methods have been only partially successful. Recently, vaccination with recombinant Boophilus microplus gut antigens has been shown to control tick infestations. Our Bm86-containing vaccine formulation (Gavac) has been effective for the control of artificial infestations of B. annulatus, B. decoloratus, and chemically sensitive and resistant B. microplus strains from Australia, Africa, America, and Iran. Preliminary results with Hyalomma spp. and Rhipicephalus spp. suggest partial cross protection. In field trials, vaccination with Gavac controlled B. microplus and B. annulatus infestations and reduced the transmission of babesiosis, resulting in important savings for the cattle industry. Different degrees of susceptibility to the vaccination with Bm86 and sequence variations in the Bm86 locus have been reported. The Bm95 antigen was isolated from the Argentinean Bm86-resistant B. microplus strain A. A Bm95-based vaccine was used to protect cattle against tick infestations under production conditions with similar results to that obtained with Gavac. The Bm95 antigen from strain A was able to protect against infestations with Bm86-sensitive and Bm86-resistant tick strains, thus suggesting that Bm95 could be a more universal antigen in protecting cattle against infestations by B. microplus strains from different geographical areas. These results clearly demonstrate the advantage and possibilities for the immunological control of ticks. PMID:11193686

  6. Avaliação in vitro de uma cepa de campo de Boophilus microplus (Acari : Ixodidae resistente à amitraz In vitro evaluation of a field strain of Boophilus microplus (Acari:Ixodidae resistant to amitraz

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    Minerva Santamaría Vargas

    2003-08-01

    Full Text Available O uso dos acaricidas químicos ainda se constitui no principal instrumento de controle do carrapato bovino Boophilus microplus. No sul do Brasil, o amitraz aplicado por imersão e aspersão é o ingrediente ativo mais utilizado, nos últimos anos, contra as cepas de carrapatos resistentes aos organofosforados (OF e piretróides sintéticos (PS. Em conseqüência, torna-se importante a realização de investigações que possam contribuir para prolongar a vida útil desse ixodicida. No presente estudo, foi analisado o comportamento toxicológico de uma cepa de B. microplus colhida na localidade de Alegrete, Rio Grande do Sul, usando-se químicos da família dos OF, PS, misturas OF/PS, além do amitraz. Os resultados indicaram que a cepa denominada "Santa Luiza" apresentou fatores de resistência (FR que variaram entre 2,3 e 3,95 para OF, 23,3 e 147,56 para PS e de 3,76 a 21.57 para amitraz em testes realizados com larvas de carrapatos. A caracterização e purificação de uma cepa de B. microplus resistente ao amitraz permitem seu uso como cepa de referência para a avaliação biológica de ixodicidas alternativos, além de padronizar e validar métodos de diagnósticos toxicológicos que possam detectar resistência frente a esse acaricida.The use of chemical acaricide still remains as the main tool against the cattle tick Boophilus microplus. In Southern Brazil, amitraz applied by immersion and/or spray is the main active ingredient to control organophosphate and synthetic pyrethroid resistant strains. In consequence it is important to conduct investigations in order to prolong useful life of this ingredient. In this article, toxicological behaviour of a strain of Boophilus microplus named "Santa Luiza" collected in the locality of Alegrete, state of Rio Grande do Sul, Brazil, was analyzed against acaricides organophosphorous, pyrethroids, mixtures SP and OP and amitraz. Results showed factors of resistance from 2.3 to 3.95 to OP, 23.3 to 147

  7. Expression of recombinant Rhipicephalus (Boophilus) microplus, R. annulatus and R. decoloratus Bm86 orthologs as secreted proteins in Pichia pastoris

    OpenAIRE

    Jongejan Frans; Hope Michelle; Nijhof Ard M; Naranjo Victoria; de la Lastra José; Canales Mario; de la Fuente José

    2008-01-01

    Abstract Background Rhipicephalus (Boophilus) spp. ticks economically impact on cattle production in Africa and other tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The R. microplus Bm86 protective antigen has been produced by recombinant DNA technology and shown to protect cattle against tick infestations. Results In this study, the genes for Bm86 (R. microplus), Ba86 (R. annulatus) and Bd86 (...

  8. Partial sequencing of Bm86 gene for studying the phylogeny of an Indian isolate of Rhipicephalus(Boophilus) microplus tick

    OpenAIRE

    Anbarasi, P.; Latha, B. R.; Dhinakar Raj, G.; Sreekumar, C.; Senthuran, S.

    2013-01-01

    Tick gut glycoprotein, designated as Bm86, found on the luminal surface of the plasma membrane of gut epithelial cells of Boophilus microplus, which is a concealed antigen, has been used as vaccine candidate molecule for immunization against ticks. To better understand the molecular diversity of Bm86 gene in ticks, a portion of the cDNA was sequenced from an Indian isolate of B. microplus. Comparison of nucleotide sequence revealed that Indian isolate had 97 % homology (18 polymorphisms) with...

  9. Infectividad de Metarhizium anisopliae en contra de cepas de garrapata Boophilus microplus sensible y resistente a los organofosforados

    OpenAIRE

    Manuel Fernández-Ruvalcaba; Elyes Zhioua; Zeferino García-Vázquez

    2005-01-01

    La infectividad del hongo entomopatogénico Metarhizium anisopliae (Metschnikoff) fue probada en contra de una cepa de Boophilus microplus (Canestrini) sensible, y otra resistente a los organofosforados, por medio de un ensayo in vitro con hembras ingurgitadas de B. microplus recién desprendidas del bovino, utilizando la cepa ECS1 de M. anisopliae. El micromiceto M. anisopliae demostró ser altamente infectivo, tanto para la cepa sensible como para la resistente a los organofosforados a la conc...

  10. Perspectives for the use of plant extracts to control the cattle tick Rhipicephalus (Boophilus microplus Perspectivas para o uso de extratos de plantas para o controle do carrapato de bovinos Rhipicephalus (Boophilus microplus

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    Lígia Miranda Ferreira Borges

    2011-06-01

    Full Text Available The evolution of resistance of Rhipicephalus (Boophilus microplus to synthetic acaricides has given rise to the need for new scientific investigations on alternative ways to control this tick. In this regard, various studies on plants have been developed in an attempt to find extracts with acaricidal properties. Evaluations on plant extracts for controlling R. (B. microplus have grown intensely over the last decade. There are many advantages from using plant extracts: for example, they can be used in organic cattle farming or even replace synthetic acaricides and they are associated with lower environmental and food contamination, slower development of resistance and lower toxicity to animals and humans. In vitro studies on plant extracts have shown promising results, but most of these extracts have not been tested on animals to validate their use. Difficulties in preparing proper formulations, differences in the chemical composition of plants of the same species due to extrinsic and intrinsic factors and sparse information on active acaricide compounds are hindrances that need to be addressed in order to enable progress within this scientific field.A evolução da resistência do Rhipicephalus (Boophilus microplus aos acaricidas sintéticos tem impulsionado novas investigações científicas sobre métodos alternativos para controlar este carrapato. Considerando isso, vários estudos com plantas têm sido desenvolvidos numa tentativa de encontrar extratos com propriedades acaricidas. Avalições de extratos de plantas para o controle de R. (B. microplus tem sido intensificadas nesta última década. Existem muitas vantagens com o uso de extratos de plantas no controle deste carrapato, como: eles podem ser utilizados na produção orgânica de bovinos, ou mesmo substituir os acaricidas sintéticos, além do mais, estão associados com baixa contaminação ambiental e dos alimentos, desenvolvimento mais lento de resistência e baixa toxicidade

  11. Immunization of cattle with synthetic peptides derived from the Boophilus microplus gut protein (Bm86).

    Science.gov (United States)

    Patarroyo, J H; Portela, R W; De Castro, R O; Pimentel, J Couto; Guzman, F; Patarroyo, M E; Vargas, M I; Prates, A A; Mendes, M A Dias

    2002-09-25

    Three synthetic peptides (SBm4912, SBm7462 and SBm19733), derived from the Bm86 glycoprotein from Boophilus microplus gut, were constructed and used to immunize cattle from a tick-free area. The immunized animals received three subcutaneous doses of the peptides, with saponin as adjuvant, at 30-day intervals. The immune response was evaluated by IgG elicited against the peptides by the detection of anti-Bm86 specific antibodies in situ and by Western blotting analysis. After tick challenge, reduction in the number, weight and oviposition capacity of engorged females was observed in the tick population that had fed on immunized animals. The results pointed a high efficacy (81.05%) for the SBm7462 synthetic peptide in relation to the others (p<0.01), demonstrating the efficiency of the immune response elicited by synthetic peptides to control the cattle tick B. microplus. PMID:12127414

  12. AVALIAÇÃO IN VITRO DE FITOTERÁPICOS NO CONTROLE DE RHIPICEPHALUS BOOPHILUS MICROPLUS

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    Carlos Augusto Nicolino

    2013-06-01

    Full Text Available The use of herbal medicines is considered an important alternative to control pests, and can reduce economic and environmental impacts the use of synthetic pesticides. The present study aimed at comparing the in vitro action of essential oils against engorged females of Rhipicephalus (Boophilus microplus. Essential oil was used Azadiracta indica (Neem, Cymbopogom nardus L. Rendle (Citronella and Cymbopogon citratus (lemon-grass in the following concentrations: 12.5%, 6%, 3% and 1%. Maximum efficiency (100% was observed for all plants at concentrations of 12.5%. At the concentration of 6% only the essential oils of neem and citronella apresntaram 100% efficiency. Citronella still showed maximum efficiency at a concentration of 3% and still got 95.30% in the lowest concentration (1%. It is concluded that the use of essential oils can be an important alternative in the control of Rhipicephalus (Boophilus microplus.O uso de fitoterápicos é considerado uma alternativa importante no controle de parasitas, e podem reduzir impactos econômicos e ambientais ao uso de pesticidas sintéticos. O presente estudo teve por objetivo avaliar comparativamente a ação in vitro de óleos essenciais contra fêmeas ingurgitadas de Rhipicephalus (Boophilus microplus. Foi utilizado óleo essencial de Azadiracta indica (Neem, Cymbopogom nardus L. Rendle (Citronela e Cymbopogon citratus (Capim-cidreira nas seguintes concentrações: 12,5%, 6%, 3% e 1%. Eficácia máxima (100% foi observada por todas as plantas nas concentrações de 12,5%. Na concentração de 6% somente os óleos essenciais de neem e citronela apresentaram eficácia de 100%. A citronela ainda apresentou eficácia máxima na concentração de 3% e ainda obteve 95,30% na menor concentração (1%. Conclui-se que a utilização de óleos essenciais pode ser uma alternativa importante no controle de Rhipicephalus (Boophilus microplus.

  13. First Molecular Characterization of Anaplasma marginale in Cattle and Rhipicephalus (Boophilus) microplus Ticks in Cebu, Philippines

    OpenAIRE

    YBAÑEZ, Adrian Patalinghug; Sivakumar, Thillaiampalam; YBAÑEZ, Rochelle Haidee Daclan; RATILLA, Jowarren Catingan; PEREZ, Zandro Obligado; GABOTERO, Shirleny Reyes; Hakimi, Hassan; KAWAZU, Shin-Ichiro; MATSUMOTO, Kotaro; Yokoyama, Naoaki; INOKUMA, Hisashi; 河津, 信一郎; 松本, 高太郎; 横山, 直明; 猪熊,壽

    2013-01-01

    Anaplasma marginale has been detected in the Philippines only by peripheral blood smear examination and serological methods. This study generally aimed to molecularly detect and characterize A. marginale in cattle and ticks in Cebu, Philippines. A total of 12 bovine blood samples and 60 Rhipicephalus (Boophilus) microplus ticks were collected on the Cebu Island in 2011. 16S rRNA-based screening-PCR and DNA sequencing revealed 8 cattle (66.7%) and 8 ticks (13.3%) to be positive for A. marginal...

  14. Biochemical characterization of the recombinant Boophilus microplus Bm86 antigen expressed by transformed Pichia pastoris cells.

    Science.gov (United States)

    Montesino, R; Cremata, J; Rodríguez, M; Besada, V; Falcón, V; de la Fuente, J

    1996-02-01

    In the present paper we report the biochemical characteristics of the recombinant tick (Boophilus microplus) gut antigen Bm86 that previously has been cloned, expressed and recovered at high levels in the methylotrophic yeast Pichia pastoris. The results demonstrate that rBm86 had a modification at position 92 (Thr replaced by Ile) and aggregated, forming particles ranging between 17 and 40 nm. The rBm86 was N-glycosylated, having at least two non-glycosylated sequons (Asn-329 and Asn-363) and a ratio of only 0.4/65 (free Cys/total Cys)/mol of protein. PMID:8867893

  15. Global comparative analysis of ESTs from the southern cattle tick, Rhipicephalus (Boophilus microplus

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    Pertea Geo

    2007-10-01

    Full Text Available Abstract Background The southern cattle tick, Rhipicephalus (Boophilus microplus, is an economically important parasite of cattle and can transmit several pathogenic microorganisms to its cattle host during the feeding process. Understanding the biology and genomics of R. microplus is critical to developing novel methods for controlling these ticks. Results We present a global comparative genomic analysis of a gene index of R. microplus comprised of 13,643 unique transcripts assembled from 42,512 expressed sequence tags (ESTs, a significant fraction of the complement of R. microplus genes. The source material for these ESTs consisted of polyA RNA from various tissues, lifestages, and strains of R. microplus, including larvae exposed to heat, cold, host odor, and acaricide. Functional annotation using RPS-Blast analysis identified conserved protein domains in the conceptually translated gene index and assigned GO terms to those database transcripts which had informative BlastX hits. Blast Score Ratio and SimiTri analysis compared the conceptual transcriptome of the R. microplus database to other eukaryotic proteomes and EST databases, including those from 3 ticks. The most abundant protein domains in BmiGI were also analyzed by SimiTri methodology. Conclusion These results indicate that a large fraction of BmiGI entries have no homologs in other sequenced genomes. Analysis with the PartiGene annotation pipeline showed 64% of the members of BmiGI could not be assigned GO annotation, thus minimal information is available about a significant fraction of the tick genome. This highlights the important insights in tick biology which are likely to result from a tick genome sequencing project. Global comparative analysis identified some tick genes with unexpected phylogenetic relationships which detailed analysis attributed to gene losses in some members of the animal kingdom. Some tick genes were identified which had close orthologues to mammalian genes

  16. Susceptibility of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) to pyrethroids and their associations in Pernambuco, Brazil.

    Science.gov (United States)

    de Santana, Breno Barros; Ramos, Rafael Antonio Nascimento; Santana, Marília de Andrade; Alves, Leucio Cãmara; de Carvalho, Gílcia Aparecida

    2013-01-01

    The synthetic pyrethroids and their associations have been widely used for controlling Rhipicephalus (Boophilus) microplus. The frequent use of acaricides has been inducing the development of resistance in the tick populations. The aim of this study was to assess the susceptibility of R. (B.) microplus populations to pyrethroids and their associations in the region of Garanhuns, Pernambuco, Brazil. In addition, the level of information among farm owners regarding tick control measures was investigated. Ticks were collected directly from naturally infested dairy cattle in the region and were exposed to pyrethroids and their associations. At the same time, an epidemiological questionnaire was applied with the aim of investigating the level of information among the farmers. The results reported here indicate that R. (B.) microplus populations in the dairy region of Garanhuns show resistance to pyrethroids and their associations, except when the product is associated with piperonyl butoxide. Regarding the results from the epidemiological survey, it was seen that there is a considerable lack of information among the farmers in relation to ixodid control measures. The level of ticks resistance to acaricides varied widely across the region studied. No alternative control programs have been implemented among these farms, thus demonstrating that there is a need for more information relating to the biology and control of R. (B.) microplus. PMID:23856731

  17. Risk factors related to resistance to Rhipicephalus (Boophilus microplus and weight gain of heifers

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    Jenevaldo Barbosa da Silva

    2015-08-01

    Full Text Available The aim of the present study was to evaluate the influence of age and genetics in dairy heifers on resistance to the cattle tick Rhipicephalus (Boophilus microplus and correlate these parameters with weight gain. Twenty-two heifers were evaluated from birth up to two years of age. Resistance to the cattle tick was evaluated by counting the number of engorged female ticks and subjective qualification of the larvae and nymph infestation. The animals were weighted in the first 24 hours after birth and at six, 12, 18 and 24 months of age. The average tick count and weight gain were compared by Tukey’s test at 5% significance. Subsequently, linear regression was performed to verify the strength of the association between the risk factors age and genetics and infestation by R. (B. microplus. Age and genetics were both significant risk factors for R. (B. microplus infestation in heifers. Between the third and sixth months of age, the animals showed a window of susceptibility to R. (B. microplus. Regardless of age, Bos taurus heifers had higher infestations than Bos indicus, crossbred F1 (½ B. taurus x ½ B. indicus and crossbred Gir-Holstein (Girolando (? B. taurus x ? B. indicus heifers. B. taurus heifers were heavier than B. indicus heifers at birth and had significantly greater weight gain (p < 0.01.

  18. Emergence of oriental theileriosis in cattle and its transmission through Rhipicephalus (Boophilus microplus in Assam, India

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    Parikshit Kakati

    2015-09-01

    Full Text Available Aim: The aim of the present study was to investigate the presence of Theileria in blood samples of crossbred and indigenous adult cows raised under unorganized small scale farming system in a Babesia and Anaplasma endemic geographical area from Assam, India and to see its transmission through Rhipicephalus (Boophilus microplus ticks. Materials and Methods: For the present study, 57 clinical cases of cattle suspected to be of hemoparasitic infections were taken into consideration. The parasites were identified based on morphology in giemsa stained blood smear followed by polymerase chain reaction (PCR. Sera samples were tested for T. annulata antibodies in plate and Dot-ELISA. PCR was also conducted in eggs of Rhipicephalus (Boophilus microplus tick collected from a Theileria orientalis positive animal. Results: PCR amplified 1124, 776, and 160 bp DNA fragments of B. bigemina (64.91%,T. orientalis(21.05% and A. marginale (14.03%, respectively. This assay further conducted in 12 T. orientalis positive blood samples with primers of Buffeli, Chitose, and Ikeda variants of T. orientalis showed 3 samples positive to Ikeda type and none for Buffeli and Chitose. Babesia bovis and Theileria annulata specific primers also did not amplify any fragment during the PCR assay of the blood samples. Further, all sera samples tested negative to T. annulata antibodies in Plate and Dot-ELISA. PCR conducted in eggs of R (B.microplus tick collected from a T. orientalis positive animal revealed presence of the parasite DNA. Gradual improvement in physical condition leading to complete recovery in 10 out of 12 T. orientalis infected clinical cases treated with buparvaquone(at 2.5mg/kg.b.wt I/M was the feedback obtained from field veterinarians and the cattle owners. Conclusion: The present investigation represents the first report of occurrence of T. orientalis in cattle of Assam with involvement of pathogenic Ikeda strain in clinical outbreaks and its possible natural

  19. In vitro activity of Artemisia annua L (Asteraceae extracts against Rhipicephalus (Boophilus microplus Atividade in vitro de extratos de Artemisia annua L (Asteraceae sobre Rhipicephalus (Boophilus microplus

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    Ana Carolina de Souza Chagas

    2011-03-01

    Full Text Available The activity of plant extracts on parasites may indicate groups of substances that are potentially useful for controlling Rhipicephalus (Boophilus microplus. The aim of the present study was to investigate the in vitro action of Artemisia annua extracts on this tick. The concentrations of the sesquiterpene lactones artemisinin and deoxyartemisinin present in plant extracts were quantified via high-performance liquid chromatography. Four extracts produced from the concentrated crude extract (CCE were evaluated on larvae using the impregnated paper method, with readings after 24 hours of incubation. The engorged females were immersed in the CCE and in its four derived extracts for five minutes, with incubation for subsequent analysis of biological parameters. The extracts were not effective on the larvae at the concentrations tested (3.1 to 50 mg.mL-1. The CCE showed greater efficacy on engorged females (EC50 of 130.6 mg.mL-1 and EC90 of 302.9 mg.mL-1 than did the derived extracts. These results tend to confirm that the action of artemisinin on engorged females of R.(B. microplus is conditional to their blood intake. In this case, in vitro methods would be inadequate for effective evaluation of the action of A. annua on R. (B. microplus.A atividade de extratos vegetais sobre parasitas pode indicar grupos de substâncias de uso potencial no controle de Rhipicephalus (Boophilus microplus. O objetivo do presente estudo foi investigar a ação in vitro de extratos de Artemisia annua sobre esta espécie. A concentração das lactonas sesquiterpênicas artemisinina e deoxiartemisinina presentes nos extratos vegetais, foi quantificada via cromatografia líquida de alta eficiência. Quatro extratos produzidos a partir do extrato bruto concentrado (EBC foram avaliados sobre larvas pela metodologia do papel impregnado, com leitura após 24 horas de incubação. As fêmeas ingurgitadas foram imersas por cinco minutos no EBC e nos seus quatro extratos

  20. Molecular and functional characterization of the first tick CAP2b (periviscerokinin) receptor from Rhipicephalus (Boophilus) microplus

    Science.gov (United States)

    The cDNA of the receptor for CAP2b/periviscerokinin (PVK) neuropeptides, designated Rhimi-CAP2b-R, was cloned from synganglia of tick Rhipicephalus (Boophilus) microplus. This receptor is the ortholog of the insect CAP2b/PVK receptor, as concluded from analyses of the predicted protein sequence, ph...

  1. Assessment of bacterial diversity in the cattle tick Rhipicephalus (Boophilus microplus through tag-encoded pyrosequencing

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    Bendele Kylie G

    2011-01-01

    Full Text Available Abstract Background Ticks are regarded as the most relevant vectors of disease-causing pathogens in domestic and wild animals. The cattle tick, Rhipicephalus (Boophilus microplus, hinders livestock production in tropical and subtropical parts of the world where it is endemic. Tick microbiomes remain largely unexplored. The objective of this study was to explore the R. microplus microbiome by applying the bacterial 16S tag-encoded FLX-titanium amplicon pyrosequencing (bTEFAP technique to characterize its bacterial diversity. Pyrosequencing was performed on adult males and females, eggs, and gut and ovary tissues from adult females derived from samples of R. microplus collected during outbreaks in southern Texas. Results Raw data from bTEFAP were screened and trimmed based upon quality scores and binned into individual sample collections. Bacteria identified to the species level include Staphylococcus aureus, Staphylococcus chromogenes, Streptococcus dysgalactiae, Staphylococcus sciuri, Serratia marcescens, Corynebacterium glutamicum, and Finegoldia magna. One hundred twenty-one bacterial genera were detected in all the life stages and tissues sampled. The total number of genera identified by tick sample comprised: 53 in adult males, 61 in adult females, 11 in gut tissue, 7 in ovarian tissue, and 54 in the eggs. Notable genera detected in the cattle tick include Wolbachia, Coxiella, and Borrelia. The molecular approach applied in this study allowed us to assess the relative abundance of the microbiota associated with R. microplus. Conclusions This report represents the first survey of the bacteriome in the cattle tick using non-culture based molecular approaches. Comparisons of our results with previous bacterial surveys provide an indication of geographic variation in the assemblages of bacteria associated with R. microplus. Additional reports on the identification of new bacterial species maintained in nature by R. microplus that may be

  2. Allopatric speciation in ticks: genetic and reproductive divergence between geographic strains of Rhipicephalus (Boophilus microplus

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    Jongejan Frans

    2009-02-01

    Full Text Available Abstract Background The cattle tick, Rhipicephalus (Boophilus microplus, economically impact cattle industry in tropical and subtropical regions of the world. The morphological and genetic differences among R. microplus strains have been documented in the literature, suggesting that biogeographical and ecological separation may have resulted in boophilid ticks from America/Africa and those from Australia being different species. To test the hypothesis of the presence of different boophilid species, herein we performed a series of experiments to characterize the reproductive performance of crosses between R. microplus from Australia, Africa and America and the genetic diversity of strains from Australia, Asia, Africa and America. Results The results showed that the crosses between Australian and Argentinean or Mozambican strains of boophilid ticks are infertile while crosses between Argentinean and Mozambican strains are fertile. These results showed that tick strains from Africa (Mozambique and America (Argentina are the same species, while ticks from Australia may actually represent a separate species. The genetic analysis of mitochondrial 12S and 16S rDNA and microsatellite loci were not conclusive when taken separately, but provided evidence that Australian tick strains were genetically different from Asian, African and American strains. Conclusion The results reported herein support the hypothesis that at least two different species share the name R. microplus. These species could be redefined as R. microplus (Canestrini, 1887 (for American and African strains and probably the old R. australis Fuller, 1899 (for Australian strains, which needs to be redescribed. However, experiments with a larger number of tick strains from different geographic locations are needed to corroborate these results.

  3. Boophilus microplus: ASPECTOS BIOLÓGICOS Y MOLECULARES DE LA RESISTENCIA A LOS ACARICIDAS Y SU IMPACTO EN LA SALUD ANIMAL

    OpenAIRE

    Delia Inés Domínguez-García; Rodrigo Rosario-Cruz; Consuelo Almazán-García; Jorge Alberto Saltijeral Oaxaca; José de la Fuente

    2010-01-01

    La aplicación de ixodicidas durante mucho tiempo ha sido la alternativa de elección para el control de la garrapata Boophilus microplus, sin embargo, actualmente el uso de los ixodicidas tiene una eficacia limitada en la reducción de las infestaciones debido al desarrollo de poblaciones de garrapatas resistes. La resistencia a ixodicidas es un problema creciente que necesita ser atendido, por que en este momento está afectando la competitividad de la ganadería y la economía de miles de produc...

  4. Identification of a synthetic peptide inducing cross-reactive antibodies binding to Rhipicephalus (Boophilus) decoloratus, Rhipicephalus (Boophilus) microplus, Hyalomma anatolicum anatolicum and Rhipicephalus appendiculatus BM86 homologues.

    Science.gov (United States)

    Kopp, Nadja; Diaz, Diana; Amacker, Mario; Odongo, David O; Beier, Konstantin; Nitsch, Cordula; Bishop, Richard P; Daubenberger, Claudia A

    2009-12-10

    The BM86 antigen, originally identified in Rhipicephalus (Boophilus) microplus, is the basis of the only commercialized anti-tick vaccine. The long-term goal of our study is to improve BM86 based vaccines by induction of high levels of tick gut binding antibodies that are also cross-reactive with a range of BM86 homologues expressed in other important tick species. Here we have used a BD86 derived synthetic peptide, BD86-3, to raise a series of mouse monoclonal antibodies. One of these mAbs, named 12.1, recognized BM86 homologues in immuno-histochemical analyses in four out of five tick species including R. (B.) microplus, Rhipicephalus (Boophilus) decoloratus, Hyalomma anatolicum anatolicum and Rhipicephalus appendiculatus. Our results indicate that broadly cross-reactive tick gut binding antibodies can be induced after immunization with a synthetic peptide derived from the protein BD86. PMID:19808026

  5. Detection of amitraz resistance in Rhipicephalus (Boophilus) microplus from North Gujarat, India.

    Science.gov (United States)

    Singh, N K; Gelot, I S; Jyoti; Singh, Veer; Rath, S S

    2015-03-01

    Amitraz has become one of the most extensively used chemical acaricide for control of cattle tick due to development of resistance against most of the organophosphates and synthetic pyrethroid acaricides. The resistance status of amitraz was evaluated against Rhipicephalus (Boophilus) microplus collected from Banaskantha district, Gujarat, India by adult immersion test (AIT). The different concentrations of amitraz utilized in the AIT were 125, 250, 500, 750 and 1,000 ppm. The adult female ticks showed an upward trend in the mortality percentage with increase in drug concentration. The regression graph of probit mortality of ticks plotted against log values of progressively increasing concentrations of amitraz was utilized for the determination of slope of mortality which was 1.868 ± 0.2068. The lethal concentration (LC95) was calculated as 3098.2 ppm and the RF was 24.78 which indicated level II resistance status. The dose response curves for egg masses, reproductive index and inhibition of oviposition of R. (B.) microplus were also validated and the slope was -0.5165 ± 0.08287, -0.1328 ± 0.04472 and 24.22 ± 8.160, respectively. The current study appears to be the pioneer report of amitraz resistance in R. (B.) microplus from India and the data generated could be of immense help to develop effective control strategies against ticks. PMID:25698859

  6. Control of Boophilus microplus populations in grazing cattle vaccinated with a recombinant Bm86 antigen preparation.

    Science.gov (United States)

    Rodríguez, M; Penichet, M L; Mouris, A E; Labarta, V; Luaces, L L; Rubiera, R; Cordovés, C; Sánchez, P A; Ramos, E; Soto, A

    1995-04-01

    Current methods for the control of cattle tick Boophilus microplus infestations are not effective and the parasite remains a serious problem for the cattle industry in tropical and subtropical areas. Recently, we developed a vaccine against B. microplus employing a recombinant Bm86 (rBm86) antigen preparation (Gavac, Heber Biotec) and it was shown to induce a protective response in vaccinated animals under controlled conditions. Here we show that, under field conditions in grazing cattle, the vaccine is able to control B. microplus populations. Two parasite-free farms were employed for the study. In the first farm, animals were vaccinated with the recombinant vaccine, while, in the second, animals received a saline injection in adjuvant. After immunization, animals were artificially infected and the infestation rate was recorded. Over the 33 weeks of the experiment, the infestation rate was lower in the vaccinated group compared with the control group. At the end of the experiment it was necessary to use chemicals in the control farm after serious losses in production and animals. PMID:7660571

  7. Protection against Boophilus annulatus infestations in cattle vaccinated with the B. microplus Bm86-containing vaccine Gavac. off.

    Science.gov (United States)

    Fragoso, H; Rad, P H; Ortiz, M; Rodríguez, M; Redondo, M; Herrera, L; de la Fuente, J

    1998-12-01

    Tick infestations by Boophilus spp. constitute a major problem for the cattle industry in tropical and subtropical areas of the world. The use of traditional control methods has been only partially successful and tick infestations remain a serious problem. Recently, the gut antigen Bm86 was isolated from B. microplus. Recombinant preparations of this antigen have been used in vaccines for the control of B. microplus infestations. However, in several regions of the world, B. microplus coexists with other Boophilus species, mainly B. annulatus and B. decoloratus. Therefore, there is a need for the simultaneous control of infestations by different Boophilus species. To test the capacity of the P. pastoris-derived Bm86 antigen preparation (Gavac, Heber Biotec S.A., Havana) to control B. annulatus infestations, controlled experiments were conducted in Mexico and Iran. Cattle were vaccinated with Gavac or not vaccinated and then artificially infested with B. annulatus larvae. The results showed for the first time a high protection efficacy (> 99.9%) of Gavac in the control of B. annulatus infestations. These results support the application of Bm86-containing vaccines for the control of Boophilus spp. infestations. PMID:9796055

  8. Isolation of the monooxygenase complex from Rhipicephalus (Boophilus) microplus - clues to understanding acaricide resistance.

    Science.gov (United States)

    Graham, Kirsty M; Sparagano, Olivier A E; Finn, Robert D

    2016-06-01

    The monooxygenase complex is composed of three key proteins, a cytochrome P450 (CYP), the cytochrome P450 oxidoreductase (CPR) and cytochrome b5 and plays a key role in the metabolism and detoxification of xenobiotic substances, including pesticides. In addition, overexpression of these components has been linked to pesticide resistance in several important vectors of disease. Despite this, the monooxygenase complex has not been isolated from the Southern cattle tick Rhipicephalus (Boophilus) microplus, a major disease vector in livestock. Using bioinformatics 115 transcriptomic sequences were analyzed to identify putative pesticide metabolizing CYPs. RACE-PCR was used to amplify the full length sequence of one CYP; CYP3006G8 which displays a high degree of homology to members of the CYP6 and 9 subfamilies, known to metabolize pyrethroids. mRNA expression levels of CYP3006G8 were investigated in 11 strains of R. microplus with differing resistance profiles by qPCR, the results of which indicated a correlation with pyrethroid metabolic resistance. In addition to this gene, the sequences for CPR and cytochrome b5 were also identified and subsequently isolated from R. microplus using PCR. CYP3006G8 is only the third CYP gene isolated from R. microplus and the first to putatively metabolize pesticides. The initial results of expression analysis suggest that CYP3006G8 metabolizes pyrethroids but further biochemical characterization is required to confirm this. Differences in the kinetic parameters of human and mosquito CPR in terms of NADPH binding have been demonstrated and could potentially be used to design species specific pesticides. Similar differences in the tick CPR would confirm that this is a characteristic of heamatophagous arthropods. PMID:26850353

  9. Sequence characterization and immunogenicity of cystatins from the cattle tick Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Parizi, Luís F; Githaka, Naftaly W; Acevedo, Carolina; Benavides, Uruguaysito; Seixas, Adriana; Logullo, Carlos; Konnai, Satoru; Ohashi, Kazuhiko; Masuda, Aoi; da Silva Vaz, Itabajara

    2013-12-01

    Various classes of endopeptidases and their inhibitors facilitate blood feeding and digestion in ticks. Cystatins, a family of tight-binding and reversible inhibitors of cysteine endopeptidases, have recently been found in several tick tissues. Moreover, vaccine trials using tick cystatins have been found to induce protective immune responses against tick infestation. However, the mode of action of tick cystatins is still poorly understood, limiting the elucidation of their physiological role. Against this background, we have investigated sequence characteristics and immunogenic properties of 5 putative cystatins from Rhipicephalus (Boophilus) microplus from Brazil and Uruguay. The similarity of the deduced amino acid sequences among cystatins from the Brazilian tick strain was 27-42%, all of which had a secretory signal peptide. The cystatin motif (QxVxG), a glycine in the N-terminal region, and the PW motif in the second hairpin loop in the C-terminal region are highly conserved in all 5 cystatins identified in this study. Four cysteine residues in the C terminus characteristic of type 2 cystatins are also present. qRT-PCR revealed differential expression patterns among the 5 cystatins identified, as well as variation in mRNA transcripts present in egg, larva, gut, salivary glands, ovary, and fat body tissues. One R. microplus cystatin showed 97-100% amino acid similarity between Brazilian and Uruguayan isolates. Furthermore, by in silico analysis, antigenic amino acid regions from R. microplus cystatins showed high degrees of homology (54-92%) among Rhipicephalus spp. cystatins. Three Brazilian R. microplus cystatins were expressed in Escherichia coli, and immunogenicity of the recombinant proteins were determined by vaccinating mice. Western blotting using mice sera indicated cross-reactivity between the cystatins, suggesting shared epitopes. The present characterization of Rhipicephalus spp. cystatins represents an empirical approach in an effort to evaluate

  10. Resistencia a los acaricidas en Rhipicephalus (Boophilus) microplus: situación actual y mecanismos de resistencia

    OpenAIRE

    Roger Iván Rodríguez-Vivas; Hodgkinson, Jane E; Trees, Alexander J.

    2012-01-01

    Rhipicephalus (Boophilus) microplus es una plaga endémica de ganado en las regiones tropicales y subtropicales del mundo, causando grandes pérdidas económicas a los productores de ganado. Acaricidas químicos han desempeñado un papel fundamental en el control de R. (B). microplus; sin embargo, como consecuencia de su uso extensivo, esta especie ha desarrollado resistencia a todas las clases principales de acaricidas en todo el mundo. Resistencia a organofosforados, piretroides sintéticos y ami...

  11. Uso de lactonas macrocíclicas para el control de la garrapata Rhipicephalus (Boophilus microplus en el ganado bovino Use of macrocyclic lactones to control the cattle tick Rhipicephalus (Boophilus microplus

    Directory of Open Access Journals (Sweden)

    RI Rodríguez-Vivas

    2010-01-01

    Full Text Available En esta revisión se describe en detalle la composición química, farmacocinética, presentación y dosis, seguridad y tiempo de retiro y la seguridad ambiental de los grupos que componen a las LM: avemectinas (ivermectina, doramectina, eprinomectina, abamectina y milbemicinas (moxidectina. Además se presenta una discusión sobre su eficacia y el problema de resistencia de Rhipicephalus (Boophilus microplus a las LM. Se concluye que las LM por su alta liposolubilidad se distribuyen ampliamente en los tejidos, siendo eficaces para el control de R. (B. microplus en el ganado bovino. La eficacia de la ivermectina, doramectina, eprinomectina, abamectina y moxidectina de corta acción es similar (> 90% de eficacia a las cuatro semanas postratamiento, PT para el control de fases adultas de R. (B. microplus; sin embargo, existen en el mercado LM de larga acción que presentan eficacia > 95% con persistencia hasta 70 días PT.An overview of the macrocyclic lactones (ML, with recent results and their effect on the control of Rhipicephalus (Boophilus microplus, is presented in this paper. This review describes in detail the chemistry, pharmacokinetics and dose presentation, security and time withdrawal and environmental safety of the groups belonging to ML: avermectins (ivermectin, doramectin, eprinomectin, abamectin and milbemycin (moxidectin. There is also a discussion on their efficacy and the problem of resistance of R. (B. microplus to ML. Finally, it is concluded that due to their high lipid solubility ML are widely distributed in tissues, being effective in the control of R. (B. microplus in cattle. The efficacy of short-acting ivermectin, doramectin, eprinomectin, abamectin and moxidectin are similar (> 90% effective after four weeks post treatment, PT to control adult stages of R. (B. microplus, however, in long-acting LM are available the market and present efficiency of > 95% with persistence up to 70 days PT.

  12. Rhipicephalus (Boophilus) microplus: expression and characterization of Bm86-CG in Pichia pastoris Rhipicephalus (Boophilus) microplus: expressão e caracterização da Bm86-CG em Pichia pastoris

    OpenAIRE

    Rodrigo Casquero Cunha; Renato Andreotti; Fábio Pereira Leivas Leite

    2011-01-01

    The cattle tick Rhipicephalus (Boophilus) microplus is responsible for great economic losses. It is mainly controlled chemically, with limitations regarding development of resistance to the chemicals. Vaccines may help control this parasite, thereby reducing tick pesticide use. In this light, we performed subcloning of the gene of the protein Bm86-GC, the homologue protein that currently forms the basis of vaccines (GavacTM and TickGardPLUS) that have been developed against cattle ticks. The ...

  13. Deltamethrin resistance in field populations of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) in Jammu and Kashmir, India.

    Science.gov (United States)

    Ahanger, R R; Godara, R; Katoch, R; Yadav, A; Bhutyal, A D S; Katoch, M; Singh, N K; Bader, M A

    2015-11-01

    Detection of resistance levels against deltamethrin in Rhipicephalus (Boophilus) microplus collected from six districts of Jammu and Kashmir (India) was carried out using the adult immersion test. The regression graphs of probit mortality of ticks plotted against log values of concentration of drug were utilised for the determination of slope of mortality, lethal concentration for 50% (LC50), 95% (LC95) and resistance factor (RF). On the basis of the data generated on mortality, egg mass weight, reproductive index and percentage inhibition of oviposition, the resistance level was categorised as I, II, III and IV. Out of these six districts, resistance to deltamethrin at level I was detected in one district (RF = 1.9), at level II in two districts (RF = 7.08-10.07) and at level IV in three districts (RF = 96.08-288.72). The data generated on deltamethrin resistance status will help in formulating tick control strategy in the region.

  14. Molecular cloning and characterization of a glycine-like receptor gene from the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

    OpenAIRE

    Flores-Fernández José Miguel; Gutiérrez-Ortega Abel; Padilla-Camberos Eduardo; Rosario-Cruz Rodrigo; Hernández-Gutiérrez Rodolfo; Martínez-Velázquez Moisés

    2014-01-01

    The cattle tick Rhipicephalus (Boophilus) microplus is the most economically important ectoparasite affecting the cattle industry in tropical and subtropical areas around the world. The principal method of tick control has relied mainly on the use of chemical acaricides, including ivermectin; however, cattle tick populations resistant to ivermectin have recently been reported in Brazil, Mexico, and Uruguay. Currently, the molecular basis for ivermectin susceptibility and resistance are not we...

  15. Vaccination with recombinant Boophilus annulatus Bm86 ortholog protein, Ba86, protects cattle against B. annulatus and B. microplus infestations

    OpenAIRE

    Jongejan Frans; Naranjo Victoria; Almazán Consuelo; Canales Mario; de la Fuente José

    2009-01-01

    Abstract Background The cattle ticks, Boophilus spp., affect cattle production in tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The recombinant B. microplus Bm86 protective antigen has been shown to protect cattle against tick infestations. Recently, the gene coding for B. annulatus Bm86 ortholog, Ba86, was cloned and the recombinant protein was secreted and purified from the yeast Pichia past...

  16. Identification and characterization of Rhipicephalus (Boophilus) microplus candidate protective antigens for the control of cattle tick infestations

    OpenAIRE

    Almazan, C.; Lagunes, R.; Villar, M.; Canales, M.; R Rosario-Cruz; Jongejan, F; de la Fuente, J.

    2009-01-01

    The cattle ticks, Rhipicephalus (Boophilus) spp., affect cattle production in tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The recombinant Rhipicephalus microplus Bm86 antigen has been shown to protect cattle against tick infestations. However, variable efficacy of Bm86-based vaccines against geographic tick strains has encouraged the research for additional tick-protective antigens. Herein, ...

  17. Binding and storage of heme by vitellin from the cattle tick, Boophilus microplus.

    Science.gov (United States)

    Logullo, C; Moraes, J; Dansa-Petretski, M; Vaz, I S; Masuda, A; Sorgine, M H F; Braz, G R; Masuda, H; Oliveira, P L

    2002-12-01

    We have previously shown (, Curr. Biol. 9, 703-706) that the cattle tick Boophilus microplus does not synthesize heme, relying solely on the recovery of the heme from the diet to make all its hemeproteins. Here we present evidence that Vitellin (VN(1)), the main tick yolk protein, is a reservoir of heme for embryo development. VN was isolated from eggs at different days throughout embryogenesis. Immediately after oviposition, Boophilus VN contains approximately one mol of heme/mol of protein. During embryo development about one third of egg VN is degraded. The remaining VN molecules bind part of the heme released. These results suggest that VN functions as a heme reservoir, binding any free heme that exceeds the amount needed for development. In vitro measurement of the binding of heme to VN showed that each VN molecule binds up to 31 heme molecules. The association of heme with VN strongly inhibits heme-induced lipid peroxidation, suggesting that binding of heme is an important antioxidant mechanism to protect embryo cells from oxidative damage. This mechanism allows this hematophagous arthropod to safely store heme obtained from a blood meal inside their eggs for future use. Taken together our data suggest that, besides its known roles, VN also plays additional functions as a heme deposit and an antioxidant protective molecule. PMID:12429132

  18. The complexity of Rhipicephalus (Boophilus microplus genome characterised through detailed analysis of two BAC clones

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    Valle Manuel

    2011-07-01

    Full Text Available Abstract Background Rhipicephalus (Boophilus microplus (Rmi a major cattle ectoparasite and tick borne disease vector, impacts on animal welfare and industry productivity. In arthropod research there is an absence of a complete Chelicerate genome, which includes ticks, mites, spiders, scorpions and crustaceans. Model arthropod genomes such as Drosophila and Anopheles are too taxonomically distant for a reference in tick genomic sequence analysis. This study focuses on the de-novo assembly of two R. microplus BAC sequences from the understudied R microplus genome. Based on available R. microplus sequenced resources and comparative analysis, tick genomic structure and functional predictions identify complex gene structures and genomic targets expressed during tick-cattle interaction. Results In our BAC analyses we have assembled, using the correct positioning of BAC end sequences and transcript sequences, two challenging genomic regions. Cot DNA fractions compared to the BAC sequences confirmed a highly repetitive BAC sequence BM-012-E08 and a low repetitive BAC sequence BM-005-G14 which was gene rich and contained short interspersed elements (SINEs. Based directly on the BAC and Cot data comparisons, the genome wide frequency of the SINE Ruka element was estimated. Using a conservative approach to the assembly of the highly repetitive BM-012-E08, the sequence was de-convoluted into three repeat units, each unit containing an 18S, 5.8S and 28S ribosomal RNA (rRNA encoding gene sequence (rDNA, related internal transcribed spacer and complex intergenic region. In the low repetitive BM-005-G14, a novel gene complex was found between to 2 genes on the same strand. Nested in the second intron of a large 9 Kb papilin gene was a helicase gene. This helicase overlapped in two exonic regions with the papilin. Both these genes were shown expressed in different tick life stage important in ectoparasite interaction with the host. Tick specific sequence

  19. Acaricides efficiency on Rhipicephalus (Boophilus) microplus from Bahia state North-Central region.

    Science.gov (United States)

    Raynal, José Tadeu; Silva, Aretha Alves Borges da; Sousa, Thiago de Jesus; Bahiense, Thiago Campanharo; Meyer, Roberto; Portela, Ricardo Wagner

    2013-01-01

    The cattle tick Rhipicephalus (Boophilus) microplus is responsible for major losses in the Brazilian livestock, mainly due to reduction in cattle productive performance. Resistance development to major classes of acaricide widely used nowadays has been extensively reported, as well as the occurrence of residues from these compounds in animal products and the environment. This study aimed to evaluate the efficiency of acaricides on R. (B.) microplus collected from rural properties in the North-Central region of Bahia State. Ticks were collected in several cattle farms in the cited region, and an in vitro acaricide efficiency assay was performed based on the immersion of ticks in acaricide solutions made according to manufacturers' recommendations. The results obtained in the experiments indicated varying degrees of efficiency of the several bases studied, with the products benzofenilurea, macrocyclic lactone and fipronil showing the highest levels of efficiency, 100%, 100% and 97.34%, respectively. It was possible to conclude that, for the region studied, there are different degrees of commercial acaricides efficiency, and many present less than 95% effectiveness, value determined as acceptable by the Brazilian legislation. PMID:23538503

  20. In vitro effects of Pilocarpus microphyllus extracts and pilocarpine hydrochloride on Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Castro, Karina Neoob de Carvalho; Lima, David Fernandes; Wolschick, Dolores; Andrade, Ivanilza Moreira de; Santos, Raimunda Cardoso Dos; Santos, Francisco José de Seixas Dos; Veras, Leiz Maria Costa; Costa-Júnior, Lívio Martins

    2016-06-01

    The aim of this study was to assess the activity of aqueous (AE) and ethanolic extracts (EE) and pilocarpine hydrochloride, which were extracted and isolated from Pilocarpus microphyllus (Jaborandi), respectively, on Rhipicephalus (Boophilus) microplus. High performance liquid chromatography (HPLC) was performed to quantify these compounds. Larval packet and adult immersion tests were conducted with different concentrations. Five AE and EE concentrations, ranging from 6.2 to 100.0 mg mL-1, and six concentrations of pilocarpine hydrochloride, ranging from 0.7 to 24.0 mg mL-1, were tested. The lethal concentration (LC50) of each extract for larvae and engorged females was calculated through Probit analysis. The concentration of pilocarpine hydrochloride obtained from the EE and the AE was 1.3 and 0.3% (m/m), respectively. Pilocarpine hydrochloride presented the highest acaricidal activity on larvae (LC50 2.6 mg mL-1) and engorged females (LC50 11.8 mg mL-1) of R.(B.) microplus, followed by the EE which presented LC50 of 56.4 and 15.9 mg mL-1, for larvae and engorged females, respectively. Such results indicate that pilocarpine hydrochloride has acaricidal activity, and may be the primary compound responsible for this activity by P. microphyllus EE. PMID:27334829

  1. In vitro effects of Pilocarpus microphyllus extracts and pilocarpine hydrochloride on Rhipicephalus (Boophilus microplus

    Directory of Open Access Journals (Sweden)

    Karina Neoob de Carvalho Castro

    2016-01-01

    Full Text Available Abstract The aim of this study was to assess the activity of aqueous (AE and ethanolic extracts (EE and pilocarpine hydrochloride, which were extracted and isolated from Pilocarpus microphyllus (Jaborandi, respectively, on Rhipicephalus (Boophilus microplus. High performance liquid chromatography (HPLC was performed to quantify these compounds. Larval packet and adult immersion tests were conducted with different concentrations. Five AE and EE concentrations, ranging from 6.2 to 100.0 mg mL–1, and six concentrations of pilocarpine hydrochloride, ranging from 0.7 to 24.0 mg mL–1, were tested. The lethal concentration (LC50 of each extract for larvae and engorged females was calculated through Probit analysis. The concentration of pilocarpine hydrochloride obtained from the EE and the AE was 1.3 and 0.3% (m/m, respectively. Pilocarpine hydrochloride presented the highest acaricidal activity on larvae (LC50 2.6 mg mL–1 and engorged females (LC50 11.8 mg mL–1 of R.(B. microplus, followed by the EE which presented LC50 of 56.4 and 15.9 mg mL–1, for larvae and engorged females, respectively. Such results indicate that pilocarpine hydrochloride has acaricidal activity, and may be the primary compound responsible for this activity by P. microphyllus EE.

  2. Fenvalerate resistance status in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) from Punjab, India.

    Science.gov (United States)

    Jyoti; Nandi, Abhijit; Singh, Harkirat; Singh, N K; Rath, S S

    2016-09-01

    Larval packet test was used for evaluating the resistance levels in Rhipicephalus (Boophilus) microplus collected from different districts of central plain zone of Punjab state, India against fenvalerate. The regression graphs of probit mortality of larvae plotted against log values of progressively increasing concentrations of fenvalerate were utilized for the estimation of lethal concentration for 50 % (LC50) and 95 % (LC95) values against various field isolates of R. (B.) microplus. The slope of mortality (95 % confidence levels) varied from 0.730 ± 0.097 (0.419-1.043) to 1.455 ± 0.281 (0.558-2.352) and the value of R(2) varied from 0.881 to 0.997. From the regression equation the values of LC50 and LC95 were recorded in range of 184.39-1,338.01 and 3,253.33-112,706.26 ppm, respectively. Among the various tick isolates resistance factors in range of 1.56-54.34 were determined and all field isolates studied were found resistant against fenvalerate. Two field isolates (Jalandhar and Ludhiana) showed level I resistance; three (Patiala, Fatehgarh Sahib and Amritsar) showed level II and Kapurthala isolate showed level IV resistance. The data generated on fenvalerate resistant status will help in judicious use of the drug and formulation of effective tick control strategy for the region. PMID:27605769

  3. [Prokaryotic expression of Bm86 gene of Boophilus microplus and optimization of the expression condition].

    Science.gov (United States)

    Ma, Mi-Ling; Guan, Gui-Quan; Li, You-Quan; Liu, Ai-Hong; Ren, Qiao-Yun; Niu, Qing-Li; Yin, Hong; Luo, Jian-Xun

    2009-12-01

    A pair of specific primers was designed based on the reported Bm86 gene of Boophilus microplus,the Bm86 gene was cloned by PCR using the plasmid pMD18-T-Bm86 as templates, and subcloned into the prokaryotic plasmid pGEX-4T-1. The recombined plasmid was transformed into E. coli BL21(DE3) and followed by expression of the protein induced by different concentration of IPTG for different time. SDS-PAGE showed that the recombinant plasmid pGEX-4T-1/Bm86 expressed a fusion protein Bm86-GST (Mr 94 000) after being induced with IPTG. High level expression of Bm86-GST was found at 1 mmol/L IPTG condition a fter incubation for 8 h at 37 degree C, and the expression level of the recombinant Bm86-GST reached up to 29% of total E coli proteins Western-blotting analysis showed that the recombinant Bm86-GST was recognized by the rabbit anti-B. microplus positive serum. PMID:20232640

  4. In vitro activity of pineapple extracts (Ananas comosus, Bromeliaceae) on Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

    Science.gov (United States)

    Domingues, Luciana Ferreira; Giglioti, Rodrigo; Feitosa, Karina Alves; Fantatto, Rafaela Regina; Rabelo, Márcio Dias; Oliveira, Márcia Cristina de Sena; Oliveira, Gilson Pereira de; Bechara, Gervasio Henrique; Chagas, Ana Carolina de Souza

    2013-07-01

    Measures to control the cattle tick, Rhipicephalus (Boophilus) microplus, based only on chemical products are becoming unsustainable, mainly because of the development of resistance. The objective of this study was to test the effect of the aqueous extract of pineapple skin (AEPS) and bromelain extracted from the stem (Sigma-Aldrich®, B4882) on engorged females and larvae of R. (B.) microplus in vitro. These substances were diluted in water and evaluated at eight concentrations. Engorged females were collected and distributed in groups of 10, with three repetitions for each treatment. After immersion in the solutions, the females were placed in an incubator for observation of survival, oviposition and larval hatching. The larval packet method was used, also with three repetitions with about 100 larvae each. The packets were incubated and the readings were performed after 24 h. The estimated reproduction and efficacy of the solutions were calculated. The LC(50) and LC(90) were estimated using the Probit procedure of the SAS program. The eight concentrations were compared within each treatment by the Tukey test. For the experiment with engorged females, the most effective concentrations were 125, 250 and 500 mg/mL: 33%, 48% and 59% for the AEPS and 27%, 51% and 55% for the bromelain. The LC(50) and LC(90) values were, respectively, 276 and 8691 mg/mL for AEPS and 373 and 5172 mg/mL for bromelain. None of the dilutions tested was effective against the larvae of R. (B.) microplus. This is the first report of the action of pineapple extracts or their constituents on cattle ticks. The results demonstrate that further studies regarding composition of tick cuticle, with evaluation of other solvents and formulations, should be conducted seeking to enhance the effect of pineapple extracts and compounds against this ectoparasite. PMID:23541882

  5. Cattle ticks in Cameroon: is Rhipicephalus (Boophilus) microplus absent in Cameroon and the Central African region?

    Science.gov (United States)

    Awa, D N; Adakal, H; Luogbou, N D D; Wachong, K H; Leinyuy, I; Achukwi, M D

    2015-03-01

    In most parts of the world, ticks are rapidly developing resistance to commonly used acaricides thus rendering control difficult. This constraint is further compounded by the introduction of new species in areas where they did not exist before. Such is the case with the introduction into and rapid spread of Rhipicephalus (Boophilus) microplus in some countries of West Africa. With the looming threat of its further spread in the region, the objective of the present study was to update knowledge on cattle ticks in Cameroon. Among 19,189 ticks collected monthly from 60 animals in 5 herds from March 2012 to February 2013, Rh. (B.) decoloratus was the most abundant species with a relative prevalence of 62.2%, followed by Amblyomma variegatum (28.4%), Rh. (B.) annulatus (0.2%), Rh. (B.) geigyi (0.03%), other Rhipicephalus spp. (8.4%) and Hyalomma spp. (0.3%). Rh. (B.) decoloratus and A. variegatum were also the most widely distributed in space. Infestation rate was generally high, with average tick count/animal of about 80 during peak periods. Tick distribution and abundance in the different sites was as varied as the underlying factors, among which the most important were management systems and climatic factors. The effects of rainfall and temperature were confounded by other factors and difficult to evaluate. However, it appears tick development depends among other factors, on a humidity threshold, above which there is not much more effect. Rh. microplus was not found during this study, but more extensive tick collections have to be done to confirm this. In conclusion, cattle tick infestation in Cameroon remains an important cause for concern. Farmers need assistance in the use and management of acaricides in order to increase their efficiency and reduce the development of resistance. Although Rh. microplus was not found, its introduction from other West African countries is imminent if adequate measures, especially in the control and limitation of animal movements

  6. Controle de larvas de Boophilus microplus por Metarhizium anisopliae em pastagens infestadas artificialmente Control of Boophilus microplus larvae by Metarhizium anisopliae in artificially infested pastures

    Directory of Open Access Journals (Sweden)

    Lúcia Mara de Souza Basso

    2005-06-01

    Full Text Available O objetivo deste trabalho foi avaliar a eficiência do controle exercido por Metarhizium anisopliae na população de Boophilus microplus, em pastagens de Brachiaria brizantha, e do híbrido Tifton 85 (Cynodon spp., artificialmente infestadas com fêmeas ingurgitadas do carrapato. Trinta canteiros com 1 m² de área cada foram distribuídos aleatoriamente. Quinze foram pulverizados com esporos do fungo e quinze controles em cada forrageira, constituindo cinco repetições de cada tratamento, foram infestados com número e peso padronizados de fêmeas ingurgitadas do ácaro. Aplicou-se o fungo, na concentração de 1,8x10(8 conídios mL-1, em três situações: pulverização antes da infestação com o carrapato, após a infestação e posterioriormente à emergência das primeiras larvas nos capins. A ação do fungo foi avaliada no 35º, 38º, 41º, 48º, 55º e 61º dia pós-infestação, por meio da contagem de larvas recuperadas. Obteve-se controle de larvas do ácaro, que, nas avaliações realizadas entre o 35º e o 48º dia pós-infestação, variou entre 87% e 94%. As médias das contagens de estágios larvares do carrapato foram menores em todas as amostragens realizadas no capim-Tifton 85, indicando que houve efeito da pastagem na ação do fungo. A situação de aplicação influencia a atividade do fungo, com melhor resultado nas coletas realizadas entre o 41º e 55º dia após infestação em B. brizantha, e aplicação dos conídios logo após a emergência das primeiras larvas.The objective of this work was to evaluate the efficiency of Metarhizium anisopliae fungus against Boophilus microplus population in Brachiaria brizantha and Tifton 85 (Cynodon pastures, artificially infested with tick engorged females. Thirty plots of 1 m² each were randomly distributed in fifteen treated and fifteen control groups per type of grass, establishing five repetitions for each treatment. Pastures were infested with engorged tick females

  7. Vaccination with recombinant Boophilus annulatus Bm86 ortholog protein, Ba86, protects cattle against B. annulatus and B. microplus infestations

    Directory of Open Access Journals (Sweden)

    Jongejan Frans

    2009-03-01

    Full Text Available Abstract Background The cattle ticks, Boophilus spp., affect cattle production in tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The recombinant B. microplus Bm86 protective antigen has been shown to protect cattle against tick infestations. Recently, the gene coding for B. annulatus Bm86 ortholog, Ba86, was cloned and the recombinant protein was secreted and purified from the yeast Pichia pastoris. Results Recombinant Ba86 (Israel strain was used to immunize cattle to test its efficacy for the control of B. annulatus (Mercedes, Texas, USA strain and B. microplus (Susceptible, Mexico strain infestations. Bm86 (Gavac and Mozambique strain and adjuvant/saline were used as positive and negative controls, respectively. Vaccination with Ba86 reduced tick infestations (71% and 40%, weight (8% and 15%, oviposition (22% and 5% and egg fertility (25% and 50% for B. annulatus and B. microplus, respectively. The efficacy of both Ba86 and Bm86 was higher for B. annulatus than for B. microplus. The efficacy of Ba86 was higher for B. annulatus (83.0% than for B. microplus (71.5%. The efficacy of Bm86 (Gavac; 85.2% but not Bm86 (Mozambique strain; 70.4% was higher than that of Ba86 (71.5% on B. microplus. However, the efficacy of Bm86 (both Gavac and Mozambique strain; 99.6% was higher than that of Ba86 (83.0% on B. annulatus. Conclusion These experiments showed the efficacy of recombinant Ba86 for the control of B. annulatus and B. microplus infestations in cattle and suggested that physiological differences between B. microplus and B. annulatus and those encoded in the sequence of Bm86 orthologs may be responsible for the differences in susceptibility of these tick species to Bm86 vaccines.

  8. Borrelia theileri: observação em carrapatos do gênero Boophilus microplus no município de Guaíba, RS, Brasil Borrelia theileri: observation on Boophilus microplus ticks in Guaiba, RS, Brazil

    Directory of Open Access Journals (Sweden)

    João Ricardo Martins

    1996-12-01

    Full Text Available Espiroquetas da espécie Borrelia theileri identificadas em uma estirpe de carrapatos Boophilus microplus provenientes do município de Guaíba, RS. A observação ocorreu no exame de hemolinfa de fêmeas adultas com 10 dias pós-repleçâo, corada por Giemsa. Não foram observadas espiroquetas em ovos provenientes de teleóginas infectadas. A detecção da estirpe infectada sugere a presença de borreliose em rebanhos bovinos, fato que eventualmente pode interferir em resultados de diagnóstico ou tornar-se motivo de preocupação em produtos derivados de sangue bovino tais como vacinas vivas contra anaplasmose e babesiose bovina.Spirochetes of species Borrelia theileri were identifica in afield-strain of the caule tick Boophilus microplus, in Guaíba, RS, Brazil. Hemolymph smears from females 10 days post-repletion were collected by gentty section of the tarsal-metatarsaijoint, and dropped onto a microscope slide, and stained by Giemsa. No spirochetes were observed in eggs squashed and stained by Giemsa from the same infected strain. The detection of B. microplus adult females infected with Borrelia theileri suggesfs the likely presence of borreliosis in bovine heras what might eventually interfere with the interpretation of diagnosis results or become cause for concern in blood products such as anaplasmosis and babesiosis live vaccines.

  9. The mitochondrial genome of a Texas outbreak strain of the cattle tick, Rhipicephalus (Boophilus) microplus, derived from whole genome sequencing Pacific Biosciences and Illumina reads.

    Science.gov (United States)

    McCooke, John K; Guerrero, Felix D; Barrero, Roberto A; Black, Michael; Hunter, Adam; Bell, Callum; Schilkey, Faye; Miller, Robert J; Bellgard, Matthew I

    2015-10-15

    The cattle fever tick, Rhipicephalus (Boophilus) microplus is one of the most significant medical veterinary pests in the world, vectoring several serious livestock diseases negatively impacting agricultural economies of tropical and subtropical countries around the world. In our study, we assembled the complete R. microplus mitochondrial genome from Illumina and Pac Bio sequencing reads obtained from the ongoing R. microplus (Deutsch strain from Texas, USA) genome sequencing project. We compared the Deutsch strain mitogenome to the mitogenome from a Brazilian R. microplus and from an Australian cattle tick that has recently been taxonomically designated as Rhipicephalus australis after previously being considered R. microplus. The sequence divergence of the Texas and Australia ticks is much higher than the divergence between the Texas and Brazil ticks. This is consistent with the idea that the Australian ticks are distinct from the R. microplus of the Americas.

  10. Artificial infestation of Boophilus microplus in beef cattle heifers of four genetic groups

    Directory of Open Access Journals (Sweden)

    Ana Mary da Silva

    2007-01-01

    Full Text Available Resistance of beef cattle heifers to the cattle tick Boophilus microplus was evaluated by artificial infestation of 66 beef cattle heifers of the following genetic groups: 16 Nelore (NE, 18 Canchim x Nelore (CN, 16 Angus x Nelore (AN and 16 Simmental x Nelore (SN. The animals, with a mean age of 16.5 months, were maintained with no chemical tick control in a Brachiaria decumbens pasture. Four artificial infestations with 20,000 B. microplus larvae were carried out 14 days apart and from day 18 to day 22 of each infestation the number of engorged female ticks (> 4.5 mm was counted on the left side of each heifer. Data were analyzed as the percentage of return (PR = percentage of ticks counted relative to the number infested, transformed to (PR¼, and as log10 (Cij + 1, in which Cij is the number of ticks in each infestation, using the least squares method with a model that included the effects of genetic group (GG, animal within GG (error a, infestation number (I, GG x I and the residual (error b. Results indicated a significant GG x I interaction, because AN and SN heifers had a higher percentage of return than CN and NE heifers, while CN heifers showed a higher percentage of return than the NE heifers only in infestations 3 and 4. Transformed percentages of return were NE = 0.35 ± 0.06, AN = 0.89 ± 0.06, CN = 0.54 ± 0.05 and SN = 0.85 ± 0.06.

  11. Bmcystatin, a cysteine proteinase inhibitor characterized from the tick Boophilus microplus

    International Nuclear Information System (INIS)

    The bovine tick Rhipicephalus (Boophilus) microplus is a blood-sucking animal, which is responsible for Babesia spp and Anaplasma marginale transmission for cattle. From a B. microplus fat body cDNA library, 465 selected clones were sequenced randomly and resulted in 60 Contigs. An open reading frame (ORF) contains 98 amino acids named Bmcystatin, due to 70% amino acid identity to a classical type 1 cystatin from Ixodes scapularis tick (GenBank Accession No. DQ066227). The Bmcystatin amino acid sequence analysis showed two cysteine residues, theoretical pI of 5.92 and Mr of 11kDa. Bmcystatin gene was cloned in pET 26b vector and the protein expressed using bacteria Escherichia coli BL21 SI. Recombinant Bmcystatin (rBmcystatin) purified by affinity chromatography on Ni-NTA-agarose column and ionic exchange chromatography on HiTrap Q column presented molecular mass of 11kDa, by SDS-PAGE and the N-terminal amino acid sequenced revealed unprocessed N-terminal containing part of pelB signal sequence. Purified rBmcystatin showed to be a C1 cysteine peptidase inhibitor with Ki value of 0.1 and 0.6nM for human cathepsin L and VTDCE (vitellin degrading cysteine endopeptidase), respectively. The rBmcystatin expression analyzed by semi-quantitative RT-PCR confirmed the amplification of a specific DNA sequence (294bp) in the fat body and ovary cDNA preparation. On the other hand, a protein band was detected in the fat body, ovary, and the salivary gland extracts using anti-Bmcystatin antibody by Western blot. The present results suggest a possible role of Bmcystatin in the ovary, even though the gene was cloned from the fat body, which could be another site of this protein synthesis

  12. Variation among Bm86 sequences in Rhipicephalus (Boophilus) microplus ticks collected from cattle across Thailand.

    Science.gov (United States)

    Kaewmongkol, S; Kaewmongkol, G; Inthong, N; Lakkitjaroen, N; Sirinarumitr, T; Berry, C M; Jonsson, N N; Stich, R W; Jittapalapong, S

    2015-06-01

    Anti-tick vaccines based on recombinant homologues Bm86 and Bm95 have become a more cost-effective and sustainable alternative to chemical pesticides commonly used to control the cattle tick, Rhipicephalus (Boophilus) microplus. However, Bm86 polymorphism among geographically separate ticks is reportedly associated with reduced effectiveness of these vaccines. The purpose of this study was to investigate the variation of Bm86 among cattle ticks collected from Northern, Northeastern, Central and Southern areas across Thailand. Bm86 cDNA and deduced amino acid sequences representing 29 female tick midgut samples were 95.6-97.0 and 91.5-93.5 % identical to the nucleotide and amino acid reference sequences, respectively, of the Australian Yeerongpilly vaccine strain. Multiple sequence analyses of these Bm86 variants indicated geographical relationships and polymorphism among Thai cattle ticks. Two larger groups of cattle tick strains were discernable based on this phylogenetic analysis of Bm86, a Thai group and a Latin American group. Thai female and male cattle ticks (50 pairs) were also subjected to detailed morphological characterization to confirm their identity. The majority of female ticks had morphological features consistent with those described for R. (B.) microplus, whereas, curiously, the majority of male ticks were more consistent with the recently re-instated R. (B.) australis. A number of these ticks had features consistent with both species. Further investigations are warranted to test the efficacies of rBm86-based vaccines to homologous and heterologous challenge infestations with Thai tick strains and for in-depth study of the phylogeny of Thai cattle ticks. PMID:25777941

  13. Comportamento de queda de fêmeas ingurgitadas do carrapato Boophilus microplus The drop-off behaviour of engorged females of the cattle tick, Boophilus microplus

    Directory of Open Access Journals (Sweden)

    Paula Hocayen de Paula

    2002-08-01

    Full Text Available A dinâmica de queda de fêmeas ingurgitadas do carrapato Boophilus microplus foi avaliada na Estação Experimental da Embrapa Gado de Leite, em Coronel Pacheco- MG, Brasil. O objetivo foi avaliar as vantagens da modificação do horário de ordenha dos bovinos, considerando a higienização do pasto, em relação ao carrapato. O experimento constou de uma fase de verão/outono e uma de inverno, para testar diferenças no ritmo de queda dos carrapatos entre as duas estações. Os resultados mostraram diferenças significativas entre as fases. No verão/outono, as fêmeas ingurgitadas apresentaram maior porcentagem de queda entre 7 e 10 horas (35,3% e no inverno entre 6 e 9 horas (19,69% e entre 14 e 17 horas (21,79%. A porcentagem de queda de fêmeas ingurgitadas no período foi de 35,15% para o sistema de ordenha de 5-8h e 13-16h e de 45,48% para o sistema de ordenha de 8-11h e 16-19h, durante os meses de verão/outono. Nos meses de inverno, o porcentual de queda foi de 40,51% e de 32,71% para os dois horários de ordenha respectivamente. Considerando o tempo que os animais permanecem estabulados para a suplementação no cocho durante o período entre as ordenhas na época seca do ano na região (maio a setembro, a porcentagem de queda de fêmeas ingurgitadas foi de 55,83% para o sistema de ordenha de 5 a 16h e de 52,36% para o sistema de ordenha de 8 a 19h.A description of the drop-off behaviour of engorged females of the tick Boophilus microplus was carried out as a result of an experiment at the Experimental Station, Embrapa Gado de Leite, Coronel Pacheco, MG, Brazil. Its objective was to evaluate any repercussions of changing the time of milking of cattle in terms of reduced recontamination of the pastures with the tick. Such possible changes in this daily cattle management routine have recently become a reality since the advent of refrigerated on-farm storage of the milk and non-daily collection by tanker truck. The field experiment

  14. Use of biotherapic in the control of the natural infestation by Boophilus microplus: pilot study Uso de bioterápico en el control de la infestación natural por Boophilus microplus: estudio piloto

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    Laerte Francisco Filippsen

    2008-03-01

    Resumen En el control de enfermedades trasmitidas por garrapatas, ha sido notada resistencia los productos químicos; la preocupación con la conservación del ambiente exige procedimientos alternativos para controlar la infestación por Boophilus microplus mundialmente. El uso de preparados bioterápicos representa una de esas alternativas. El objetivo de este estudio fue evaluar el efecto de una mezcla bioterápica incluyendo B. microplus en ganado infestado naturalmente. 27 animales fueron divididos en 3 grupos (n=9: I control, sin tratamiento; II tratado con banho de amitraz; III tratado con mezcla comercial de bioterápicos 12cH, vía oral. El grupo III presentó una disminución estadísticamente significativa de garrapatas en comparación al grupo control (p Palabras-clave: Bioterapicos; Garrapatas; control alternativo; Ganado.   Correspondence author: Alessandro P. Minho. apminho@iapar.br; http://www.iapar.br; Instituto Agronômico do Paraná (IAPAR-PR, Brazil. How to cite this article: Silva NL, Moletta JL, Minho AP, Filippsen LF. Use of biotherapic in the control of natural infestation by Boophilus microplus: pilot study. Int J High Dilution Res [online]. 2008 [cited DD Mmm YYYY]; 7 (22: 36-38. Available from http://www.feg.unesp.br/~ojs/index.php/ijhdr/article/view/251/337.  En el control de enfermedades trasmitidas por garrapatas, ha sido notada resistencia los productos químicos; la preocupación con la conservación del ambiente exige procedimientos alternativos para controlar la infestación por Boophilus microplus mundialmente. El uso de preparados bioterápicos representa una de esas alternativas. El objetivo de este estudio fue evaluar el efecto de una mezcla bioterápica incluyendo B. microplus en ganado infestado naturalmente. 27 animales fueron divididos en 3 grupos (n=9: I control, sin tratamiento; II tratado con

  15. The Rhipicephalus (Boophilus) microplus Bm86 gene plays a critical role in the fitness of ticks fed on cattle during acute Babesia bovis infection

    OpenAIRE

    Knowles Donald P; Ueti Massaro W; Bastos Reginaldo G; Scoles Glen A

    2010-01-01

    Abstract Background Rhipicephalus (Boophilus) microplus is an economically important tick of cattle involved in the transmission of Babesia bovis, the etiological agent of bovine babesiosis. Commercial anti-tick vaccines based on the R. microplus Bm86 glycoprotein have shown some effect in controlling tick infestation; however their efficacy as a stand-alone solution for tick control has been questioned. Understanding the role of the Bm86 gene product in tick biology is critical to identifyin...

  16. Two initial vaccinations with the Bm86-based Gavacplus vaccine against Rhipicephalus (Boophilus) microplus induce similar reproductive suppression to three initial vaccinations under production conditions

    OpenAIRE

    Fernández Erlinda; Suárez Marisela; Lleonart Ricardo; Méndez Luis; Rodríguez Elsa; Machado Héctor; Joglar Marisdania; Alfonso Aymé; Valdés Mario; Pérez Danny; Sánchez Dunia; Montero Carlos; Vargas Milagros; Estrada Mario P; Rodríguez-Mallón Alina

    2010-01-01

    Abstract Background The cattle tick, Rhipicephalus (Boophilus) microplus, affects livestock production in many regions of the world. Up to now, the widespread use of chemical acaricides has led to the selection of acaricide-resistant ticks and to environmental contamination. Gavacplus is a subunit vaccine based on the recombinant Bm86 tick antigen expressed in yeast, capable to control infestations of R. microplus under controlled and production conditions. The vaccine constitutes the core el...

  17. Abordagem sobre o controle do carrapato Rhipicephalus (Boophilus microplus no sul do Rio Grande do Sul Studies of the management of the tick Rhipicephalus (Boophilus microplus in southern Rio Grande do Sul, Brazil

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    Tânia Regina B. Santos

    2009-01-01

    Full Text Available Na região sul do Rio Grande do Sul a infestação dos bovinos por Rhipicephalus (Boophilus microplus ocorre, principalmente, entre os meses de outubro e abril, devido às condições climáticas. Além do conhecimento do ciclo biológico desse parasito, também é fundamental conhecer a epidemiologia, para estabelecer estratégias de controle. No Rio Grande do Sul, e também no Brasil, existem poucos estudos epidemiológicos a respeito da resistência aos acaricidas. Além disso, a grande área geográfica e a deficiência estrutural quanto ao uso e acesso a bancos de dados dificultam a obtenção de dados confiáveis. O presente estudo teve como objetivo realizar um inquérito abordando a percepção dos produtores da região sul do Rio Grande do Sul, quanto à identificação de populações de R. (B. microplus difíceis de controlar com acaricidas e os fatores de risco para a seleção de populações de carrapatos resistentes. Para execução do trabalho foram coletados dados sobre o controle do carrapato de bovinos de corte, em 85 propriedades de sete municípios, localizados na região sul do Estado. Os resultados revelaram a existência de associação positiva entre a dificuldade de controlar o carrapato com os acaricidas e o grau de instrução do proprietário (até o ensino fundamental com OR=3,67 e p=0,01 e o número de aplicação de carrapaticida por ano (superior a 4 com OR=4,05 e p=0,006. Esses resultados indicam também que propriedades com mais de 100 bovinos de corte em criação extensiva, na região sul do rio Grande do Sul apresentam características que podem contribuir para uma maior vida útil dos carrapaticidas do que as verificadas em outras regiões do País.In the southern region of Rio Grande do Sul, cattle become infested with Rhipicephalus (B. microplus mainly between October and April due to the climatic conditions. In addition to knowing its life cycle, knowledge of parasite's epidemiology is essential to

  18. Bovine immunoprotection against Rhipicephalus (Boophilus microplus with recombinant Bm86-Campo Grande antigen Imunoproteção de bovinos contra Rhipicephalus (Boophilus microplus com antígeno recombinante Bm86-Campo Grande

    Directory of Open Access Journals (Sweden)

    Rodrigo Casquero Cunha

    2012-09-01

    Full Text Available The southern cattle fever tick, Rhipicephalus (Boophilus microplus, is no doubt the most economically important ectoparasite of cattle globally. The inappropriate use of chemical acaricides has driven the evolution of resistance in populations of R. (B. microplus. Anti-tick vaccines represent a technology that can be combined with acaricides in integrated control programs to mitigate the impact of R. (B. microplus. The recombinant form of Bm86 antigen from the Campo Grande (rBm86-CG strain of R. (B. microplus was produced using the Pichiapastoris expression system to test its ability to immunoprotect cattle against tick infestation. Secretion of rBm86-CG by P. pastoris through the bioprocess reported here simplified purification of the antigen. A specific humoral immune response was detected by ELISA in vaccinated cattle. Immunoblot results revealed that polyclonal antibodies from vaccinated cattle recognized a protein in larval extracts with a molecular weight corresponding to Bm86. The rBm86-CG antigen showed 31% efficacy against the Campo Grande strain of R. (B. microplus infesting vaccinated cattle. The rBm86-CG is an antigen that could be used in a polyvalent vaccine as part of an integrated program for the control of R. (B. microplus in the region that includes Mato Grosso do Sul.O carrapato Rhipicephalus (Boophilus microplus é, sem dúvidas, o ectoparasito economicamente mais importante para o gado a nível mundial. A utilização inadequada de acaricidas tem impulsionado a evolução da resistência em populações de R. (B. microplus. Vacinas contra o carrapato representam uma tecnologia que pode ser combinada com acaricidas em programas de controle integrado para diminuir o impacto de R. (B. microplus. A forma recombinante da Bm86 da cepa Campo Grande (rBm86-CG de R. (B. microplus foi produzido utilizando o sistema de expressão em Pichia pastoris para testar sua capacidade de imunoproteção ao gado contra a infestação de

  19. Pharmacological characterization of a tyramine receptor from the southern cattle tick, Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Gross, Aaron D; Temeyer, Kevin B; Day, Tim A; Pérez de León, Adalberto A; Kimber, Michael J; Coats, Joel R

    2015-08-01

    The southern cattle tick (Rhipicephalus (Boophilus) microplus) is a hematophagous external parasite that vectors the causative agents of bovine babesiosis or cattle tick fever, Babesia bovis and B. bigemina, and anaplasmosis, Anaplasma marginale. The southern cattle tick is a threat to the livestock industry in many locations throughout the world. Control methods include the use of chemical acaricides including amitraz, a formamidine insecticide, which is proposed to activate octopamine receptors. Previous studies have identified a putative octopamine receptor from the southern cattle tick in Australia and the Americas. Furthermore, this putative octopamine receptor could play a role in acaricide resistance to amitraz. Recently, sequence data indicated that this putative octopamine receptor is probably a type-1 tyramine receptor (TAR1). In this study, the putative TAR1 was heterologously expressed in Chinese hamster ovary (CHO-K1) cells, and the expressed receptor resulted in a 39-fold higher potency for tyramine compared to octopamine. Furthermore, the expressed receptor was strongly antagonized by yohimbine and cyproheptadine, and mildly antagonized by mianserin and phentolamine. Tolazoline and naphazoline had agonistic or modulatory activity against the expressed receptor, as did the amitraz metabolite, BTS-27271; however, this was only observed in the presence of tyramine. The southern cattle tick's tyramine receptor may serve as a target for the development of anti-parasitic compounds, in addition to being a likely target of formamidine insecticides. PMID:25958152

  20. Cross-resistance between fipronil and lindane in Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Castro Janer, E; Klafke, G M; Capurro, M L; Schumaker, T T S

    2015-05-30

    The southern cattle tick, Rhipicephalus (Boophilus) microplus (Canestrini), is one of the most damaging parasites of cattle in tropical and subtropical regions. Several chemical groups have been used for its control, including cyclodienes (lindane and dieldrin). In Uruguay and Brazil these products were used at the beginning of the 1960s and during a few years. Fipronil and lindane act on the same target site. In both countries, southern cattle tick resistance to fipronil has sometimes developed quickly after only a few acaricide treatments (three to seven). The objective of the present study was to determine cross-resistance between fipronil and lindane in southern cattle ticks from Uruguay and Brazil. Initially, the FAO's (Food and Agricultural Organization) larval packet test with lindane was applied to a fipronil-resistant strain and to susceptible field populations. Mozo and POA strains were used as the susceptible controls. A larval immersion test was used to assess fipronil toxicity. Of fifteen fipronil-resistant field populations that were tested with lindane, eleven were lindane-resistant and three were susceptible. The last three populations had incipient resistance to fipronil. Finally, cross-resistance between fipronil and lindane in the southern cattle tick is reported in this study for the first time. PMID:25868846

  1. Seroepidemiological study of Babesia bovis in support of the Uruguayan Boophilus microplus control programme

    International Nuclear Information System (INIS)

    Bovine blood samples were collected from a region endemic for Boophilus microplus and consisting of 125 ranches with a cattle population of 76,918. A total of 1,728 cattle were bled (1,485 adults and 243 calves less from 1 year of age) from 27 ranches. This sample size was determined to provide incidence and prevalence values with a precision of ±10% at a confidence level of 95%. The FAO/IAEA ELISA kit was used to detect antibody to Babesia bovis. Dispersion (proportion of ranches with babesia infection) was estimated to be 70.5% ± 8.8 (SD). A positive ranch was defined as having one or more test-positive animals. Apparent prevalence (proportion of cattle with a positive test result) within the region was estimated to be 3.5% ± 0.3, with a range from 0 to 18.5%. Incidence based on apparent prevalence in calves less than 1 year of age was estimated to be 2.8%. The dispersion, apparent prevalence, and incidence data for this region of Uruguay will be compared through a repeated sampling of cattle in this area during a three-year period to assess the effectiveness of the eradication/control campaign. (author)

  2. Rhipicephalus (Boophilus) microplus: expression and characterization of Bm86-CG in Pichia pastoris.

    Science.gov (United States)

    Cunha, Rodrigo Casquero; Andreotti, Renato; Leite, Fábio Pereira Leivas

    2011-01-01

    The cattle tick Rhipicephalus (Boophilus) microplus is responsible for great economic losses. It is mainly controlled chemically, with limitations regarding development of resistance to the chemicals. Vaccines may help control this parasite, thereby reducing tick pesticide use. In this light, we performed subcloning of the gene of the protein Bm86-GC, the homologue protein that currently forms the basis of vaccines (Gavac(TM) and TickGard(PLUS)) that have been developed against cattle ticks. The subcloning was done in the pPIC9 expression vector, for transformation in the yeast Pichia pastoris. This protein was characterized by expression of the recombinant Mut+ strain, which expressed greater quantities of protein. The expressed protein (rBm86-CG) was recognized in the Western-blot assay using anti-Gavac, anti-TickGard, anti-larval extract and anti-rBm86-CG polyclonal sera. The serum produced in cattle vaccinated with the antigen CG rBm86 presented high antibody titers and recognized the native protein. The rBm86-GC has potential relevance as an immunogen for vaccine formulation against cattle ticks. PMID:21722483

  3. Polymorphism of the bm86 gene in South American strains of the cattle tick Boophilus microplus.

    Science.gov (United States)

    Sossai, Sidimar; Peconick, Ana P; Sales-Junior, Policarpo A; Marcelino, Francismar C; Vargas, Marlene I; Neves, Elisangela S; Patarroyo, Joaquín H

    2005-01-01

    Thirty Boophilus microplus strains from various geographic regions of Brazil, Argentina, Uruguay, Venezuela and Colombia were analyzed for the bm86 and bm95 gene. A fragment of cDNA of 794 base pairs of the parasite larvae, included between nucleotides 278-1071s, was amplified and cloned on the pGEM-T vector. Two random clones were sequenced for each population and the nucleotides 278-1071 and predicted amino acid sequences compared with the bm86 and bm95 genes. Variations from 1.76 to 3.65% were detected in the nucleotides sequence when compared with the homologous sequence of the bm86 gene and a 3.4-6.08% in the homologous amino acid sequence of the Bm86 protein. When the sequences obtained were compared with the bm95 gene, variations from 0.50 to 3.15% were detected. Variations from 1.14 to 4.56% were detected for the Bm95 protein homologous sequences in the deduced amino acid sequence. Only five of the 30 strains analyzed presented two different types of alleles expressed and the two alleles of the Alegre population and allele 1 of the Betim population were the most divergent of all those analyzed. PMID:16323051

  4. Vaccination of cattle against the Boophilus microplus using a mucin-like membrane glycoprotein.

    Science.gov (United States)

    McKenna, R V; Riding, G A; Jarmey, J M; Pearson, R D; Willadsen, P

    1998-07-01

    An antigen, BMA7, which induced partial immunity against tick infestation has been isolated from Boophilus microplus using two different protein fractionation protocols, accompanied by vaccination and parasite challenge trails. The antigen is a 63 kDa glycoprotein isolated from semi-engorged adult female ticks. Though significant, the induced immunity is less striking than that previously reported for antigen Bm86 from the same parasite. However, co-vaccination with Bm86 and BMA7 can enhance immunity over that seen with a commercial vaccine based on Bm86 alone. Limited peptide sequence information shows significant variation in the BMA7 protein occurs. The antigen has approximately 36 kDa of glycosylation, in both N-linked and O-linked oligosaccharides. There is evidence that both polypeptide and oligosaccharide are antigenic, but the chemical nature of the protective antigenic sites is not clear. There is little or no immunological response to the antigen during natural infestation with parasites, suggesting the antigen is 'concealed' and protective immunity dependent on artificial vaccination. The antigen has some similarities with the vertebrate mucins. It is widely distributed in tick tissues and membrane bound but its function is currently unknown. PMID:9717194

  5. Identificación de un polimorfismo del gen Est9 relacionado con resistencia a piretroides en Rhipicephalus (Boophilus microplus

    Directory of Open Access Journals (Sweden)

    Edgar Diaz R.

    2013-10-01

    Full Text Available Objetivo. Mediante procedimientos de PCR-RFLP, detectar un polimorfismo en el gen Est9 de garrapatas Rhipicephalus (Boophilus microplus resistentes a piretroides en Ibagué, Colombia, determinando el grado de asociación entre los fenotipos y los genotipos resultantes. Materiales y métodos. El ADN de 30 teleoginas R. (Boophilus microplus fenotípicamente susceptibles, resistentes o medianamente resistentes a piretroides en una prueba de Drummond modificada, fue amplificado por PCR con cebadores específicos para obtener un fragmento de 372 pb del gen Est9, que fue sometido a digestión con la enzima EcoRI para estudiar los RFLPs generados y poder diferenciar los respectivos genotipos. El grado de asociación entre los fenotipos y los genotipos resultantes se determinó mediante la prueba exacta de Fisher. Resultados. Luego de digerir el fragmento con la endonucleasa, se generaron dos segmentos en teleoginas con algún nivel de resistencia, mientras en las teleoginas susceptibles no hubo división del fragmento de 372 pb, demostrándose así la presencia de una mutación puntual y los genotipos homocigoto natural, homocigoto mutante y heterocigoto. Las diferencias altamente significativas (p<0.01 entre teleoginas susceptibles y aquellas con algún nivel de resistencia, mostraron una relación directa entre el genotipo y el fenotipo con un nivel de confianza de p=0.0009852. Conclusiones. Se comprobó, por primera vez en Colombia, la presencia de una mutación puntual en el gen Est9 de garrapatas R. (Boophilus microplus resistentes a piretroides, sugiriendo la necesidad de realizar estudios para detectar alteraciones moleculares en otros genes relacionados con quimioresistencia.

  6. Suscetibilidade de Rhipicephalus (Boophilus microplus a carrapaticidas em Mato Grosso do Sul, Brasil Susceptibility of Rhipicephalus (Boophilus microplus to acaricides in Mato Grosso do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Alberto Gomes

    2011-08-01

    Full Text Available O carrapato bovino, Rhipicephalus (Boophilus microplus, destaca-se dentre os ectoparasitas de importância econômica à pecuária nacional, tornando-se necessária a adoção de medidas de controle, particularmente em rebanhos Bos taurus e seus cruzamentos. O controle do carrapato tem sido cada vez mais difícil devido à constatação de populações resistentes aos diversos produtos em uso. Neste estudo, teve-se por objetivo conhecer a suscetibilidade desse carrapato a acaricidas em Mato Grosso do Sul. De outubro de 2003 a outubro de 2006, testes carrapaticidogramas foram realizados em onze das principais regiões pecuárias do estado. Nos testes de suscetibilidade, foi utilizada a técnica de imersão de adultos, com posterior avaliação de parâmetros biológicos. Foram testados doze acaricidas comerciais, abrangendo sete princípios ativos (isoladamente ou em associação, pertencentes a três grupos químicos: amidinas (amitraz, piretróides sintéticos (cipermetrina e organofosforados (clorfenvinfós, clorpirifós, diazinon, diclorvós e etion. Baixa suscetibilidade foi detectada em todas as propriedades, evidenciando uma reduzida eficácia de todos os grupos químicos testados. Apesar da grande variação de suscetibilidade demonstrada pelas distintas populações a cada acaricida testado, foi possível observar um gradiente de eficácia desses produtos. Independente da classe, a eficácia média dos produtos com um único princípio ativo (19,94%-64,27% foi, de modo geral, menor que a das associações, tanto entre piretróide e organofosforados (46,38%-82,68%, como exclusivamente entre organofosforados (85,28%-97,68%. A associação contendo piretróide, organofosforados, sinergista e repelente (cipermetrina + clorpirifós + butóxido de piperonila + citronelal apresentou 100% de eficácia, embora testada em menor número de populações. Embora comparações com cepas suscetíveis não tenham sido efetuadas, a baixa suscetibilidade

  7. Acaricidal activity of Palicourea marcgravii, a species from the Amazon forest, on cattle tick Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Silva, Wilson Castro; Martins, João Ricardo de Souza; Cesio, Maria Veronica; Azevedo, João Lúcio; Heinzen, Horacio; de Barros, Neiva Monteiro

    2011-06-30

    Leaves of Palicourea marcgravii were extracted successively with hexane, ethyl acetate and ethanol in order to evaluate their acaricidal activity on larvae and adult stages of the cattle tick Rhipicephalus (Boophilus) microplus. The ethyl acetate extract showed the highest bioactivity of the tested extracts, which contained 0.12% monofluoroacetic acid. On engorged female, the ethyl acetate extract showed a lethal concentration 50% - LC(50)=30.08 mg ml(-1), inhibitory concentration 50% - IC(50)=5.79 mg ml(-1) and lethal time 50% - LT(50)=4.72 days; 100% reproduction was controlled at concentrations of 50 mg ml(-1) and on larvae the ethyl acetate extract showed a LC(50)=2.46 mg ml(-1). No alkaloids were detected in any of the extracts. This is the first report on the acaricidal activity of P. marcgravii extracts against R. microplus as well as the acaricidal properties of a plant species containing monofluoroacetic acid. PMID:21411227

  8. Partial sequencing of Bm86 gene for studying the phylogeny of an Indian isolate of Rhipicephalus (Boophilus) microplus tick.

    Science.gov (United States)

    Anbarasi, P; Latha, B R; Dhinakar Raj, G; Sreekumar, C; Senthuran, S

    2014-09-01

    Tick gut glycoprotein, designated as Bm86, found on the luminal surface of the plasma membrane of gut epithelial cells of Boophilus microplus, which is a concealed antigen, has been used as vaccine candidate molecule for immunization against ticks. To better understand the molecular diversity of Bm86 gene in ticks, a portion of the cDNA was sequenced from an Indian isolate of B. microplus. Comparison of nucleotide sequence revealed that Indian isolate had 97 % homology (18 polymorphisms) with that of the Australian isolate and 96 % homology (20 polymorphisms) with that of the Cuban vaccine strain. Further, the Indian isolate differed from the Cuban vaccine isolate at 7 amino acid loci, including 5 substitutions (at residues 88, 94, 175, 176 and 177) and 2 deletions (at 183 and 184). However, protein prediction studies did not show any difference in the putative antigenic epitopes of the protein expressed. PMID:25035581

  9. Efecto ixodicida de los extractos etanólicos de algunas plantas sobre garrapatas Rhipicephalus (Boophilus) microplus

    OpenAIRE

    Ángela Rodríguez S.; Carlos Rodríguez M.; Anastasia Cruz C.

    2010-01-01

    Objetivo. Evaluar in vitro, el efecto ixodicida del extracto etanólico de cinco plantas; Brugmasia arborea, Sambucus nigra, Nicotiana tabacum, Bidens pilosa y Ambrosia cumanenses sobre garrapatas adultas de la especie Rhipicephalus (Boophilus) microplus. Materiales y métodos. El extracto de cada planta fue obtenido mediante la técnica de lixiviación. Para las pruebas, se utilizaron garrapatas adultas de dos tamaños (pequeñas y medianas), que fueron expuestas a los extractos de cada planta, ut...

  10. Molecular cloning and characterization of a glycine-like receptor gene from the cattle tick Rhipicephalus (Boophilus microplus (Acari: Ixodidae

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    Flores-Fernández José Miguel

    2014-01-01

    Full Text Available The cattle tick Rhipicephalus (Boophilus microplus is the most economically important ectoparasite affecting the cattle industry in tropical and subtropical areas around the world. The principal method of tick control has relied mainly on the use of chemical acaricides, including ivermectin; however, cattle tick populations resistant to ivermectin have recently been reported in Brazil, Mexico, and Uruguay. Currently, the molecular basis for ivermectin susceptibility and resistance are not well understood in R. microplus. This prompted us to search for potential molecular targets for ivermectin. Here, we report the cloning and molecular characterization of a R. microplus glycine-like receptor (RmGlyR gene. The characterized mRNA encodes for a 464-amino acid polypeptide, which contains features common to ligand-gated ion channels, such as a large N-terminal extracellular domain, four transmembrane domains, a large intracellular loop and a short C-terminal extracellular domain. The deduced amino acid sequence showed around 30% identity to GlyRs from some invertebrate and vertebrate organisms. The polypeptide also contains the PAR motif, which is important for forming anion channels, and a conserved glycine residue at the third transmembrane domain, which is essential for high ivermectin sensitivity. PCR analyses showed that RmGlyR is expressed at egg, larval and adult developmental stages. Our findings suggest that the deduced receptor is an additional molecular target to ivermectin and it might be involved in ivermectin resistance in R. microplus.

  11. Esterase profile in a pyrethroid-resistant Brazilian strain of the cattle tick Boophilus microplus (Acari, Ixodidae

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    Milla Alves Baffi

    2005-12-01

    Full Text Available The cattle tick Boophilus microplus causes great damage in livestock and is considered one of the most important tropical ectoparasites. The traditional method of control is based on the intensive use of pesticides, however the indiscriminate use of these compounds over the years has led to the selection of resistant ticks. Hydrolases, particularly esterases (EST, have been reported to be associated with acaricide resistance in B. microplus. We compared the esterase profile of susceptible and cypermethrin-resistant strains of adult B. microplus and a pyrethroid susceptible reference strain (the Mozzo strain using polyacrylamide gel electrophoresis and specific staining. The electrophoretic profiles of protein extracts revealed the presence of four regions with esterase activity in the cypermethrin-resistant strain and three of these regions in the susceptible strains. The bands were numbered EST-1 to EST-4 in sequence (starting from the anode according to their decrease in negative charge. The EST-1A and EST-1B enzymes were detected only in the resistant strain. The inhibition studies with eserine sulfate, copper sulfate, p- p-chloromercuribenzoate (pCMB, malathion and phenylmethylsulfonyl fluoride (PMSF indicated that the EST-1A and EST-1B enzymes belong to the acetylcholinesterase class and are probably associated with resistance to acaricides in this Brazilian resistant strain of B. microplus.

  12. Molecular cloning and characterization of a glycine-like receptor gene from the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

    Science.gov (United States)

    Flores-Fernández, José Miguel; Gutiérrez-Ortega, Abel; Padilla-Camberos, Eduardo; Rosario-Cruz, Rodrigo; Hernández-Gutiérrez, Rodolfo; Martínez-Velázquez, Moisés

    2014-01-01

    The cattle tick Rhipicephalus (Boophilus) microplus is the most economically important ectoparasite affecting the cattle industry in tropical and subtropical areas around the world. The principal method of tick control has relied mainly on the use of chemical acaricides, including ivermectin; however, cattle tick populations resistant to ivermectin have recently been reported in Brazil, Mexico, and Uruguay. Currently, the molecular basis for ivermectin susceptibility and resistance are not well understood in R. microplus. This prompted us to search for potential molecular targets for ivermectin. Here, we report the cloning and molecular characterization of a R. microplus glycine-like receptor (RmGlyR) gene. The characterized mRNA encodes for a 464-amino acid polypeptide, which contains features common to ligand-gated ion channels, such as a large N-terminal extracellular domain, four transmembrane domains, a large intracellular loop and a short C-terminal extracellular domain. The deduced amino acid sequence showed around 30% identity to GlyRs from some invertebrate and vertebrate organisms. The polypeptide also contains the PAR motif, which is important for forming anion channels, and a conserved glycine residue at the third transmembrane domain, which is essential for high ivermectin sensitivity. PCR analyses showed that RmGlyR is expressed at egg, larval and adult developmental stages. Our findings suggest that the deduced receptor is an additional molecular target to ivermectin and it might be involved in ivermectin resistance in R. microplus. PMID:25174962

  13. Evidence for the utility of the Bm86 antigen from Boophilus microplus in vaccination against other tick species.

    Science.gov (United States)

    de Vos, S; Zeinstra, L; Taoufik, O; Willadsen, P; Jongejan, F

    2001-01-01

    The Bm86 antigen, as originally identified in Boophilus microplus, is the basis of commercial tick vaccines against this tick species. The potential for using this antigen or homologues of the antigen in vaccination against other tick species has been assessed. We have conducted vaccine trials in cattle using the B. microplus-derived recombinant Bm86 vaccine (TickGARD) using pairs of vaccinated calves and control calves. These were infested with B. microplus and Boophilus decoloratus larvae simultaneously. For both species, the numbers of engorged female adult ticks, their weight and egg-laying capacity were all reduced, leading to a reduction in reproductive capacity of 74% for B. microplus and 70% for B. decoloratus. Hyalomma anatolicum anatolicum ticks were fed both as immatures as well as adults on vaccinated calves and non-vaccinated controls. There was an overall 50% reduction in the total weight of nymphs engorging on vaccinated calves, and a suggestion of a subsequent effect on feeding adults. For Hyalomma dromedarii there was a 95% reduction in the number of nymphs engorging and a further 55% reduction in weight of those ticks surviving. Rhipicephalus appendiculatus and Amblyomma variegatum ticks were fed simultaneously both as immatures and subsequently as adults. There was no evidence for a significant vaccination effect. Finally, the amino acid sequence of a Bm86 homologue found in H. a. anatolicum unequivocally demonstrated the conservation of this molecule in this species. Our strategy for the development of multivalent anti-tick vaccines is discussed in relation to these findings. PMID:11523920

  14. Discovery, adaptation and transcriptional activity of two tick promoters: Construction of a dual luciferase reporter system for optimization of RNA interference in Rhipicephalus (Boophilus) microplus cell lines

    Science.gov (United States)

    Dual luciferase reporter systems are valuable tools for functional genomic studies, but have not previously been developed for use in tick cell culture. We evaluated expression of available luciferase constructs in tick cell cultures derived from Rhipicephalus (Boophilus) microplus, an important vec...

  15. Efficiency of tick biotherapic on the control of infestation by Rhipicephalus (Boophilus microplus in Dutch dairy cows.

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    Cesar Alberto Coutinho

    2010-12-01

    Full Text Available Background: cattle tick Rhipicephalus (Boophilus microplus poses serious problems for farmers in Brazil, especially because the parasite easily develops resistance to pesticide agents. For this reason, together with other factors including environmental, human and animal contamination and costs, alternative approaches have been sought for. Aims: this study sough to evaluate the efficiency of a tick biotherapic on tick-infested cows. Methods: 34 dairy Dutch cows were divided in 2 groups: one group received 100g/day of mineral salt supplement impregnated with tick biotherapic 12cH for 6 months, and then in alternate days with tick biotherapic 30cH to complete 28 months of treatment; the other group (control received only the mineral salt supplement. After 28 months of treatment, engorged Rhipicephalus (boophilus microplus females were collected in both groups, counted and weighed; in vitro tests were carried out to assess mass of ticks; egg mass; egg-hatching rate; and reproductive efficiency. Results: There was significant difference between both groups for all parameters evaluated; tick-mass (p = 0.0008; egg mass (p=0.0044; egg-hatching rate (p= 0.0017; and reproductive efficiency (p = 0.0044. Conclusion: treatment with tick biotherapic significantly decreased the mass of engorged females, deposition and hatching rate of eggs, resulting consequently in the decrease of the reproductive efficiency of ticks.

  16. Rhipicephalus (Boophilus) microplus in the western-central region of Rio Grande do Sul, Brazil: multiresistant tick.

    Science.gov (United States)

    Machado, Fabrício Amadori; Pivoto, Felipe Lamberti; Ferreira, Maiara Sanitá Tafner; Gregorio, Fabiano de Vargas; Vogel, Fernanda Silveira Flores; Sangioni, Luís Antônio

    2014-01-01

    The aim of the present study was to assess the acaricide resistance of tick populations in the western-central region of Rio Grande do Sul (Brazil), which has not previously been reported. Fifty-four cattle farms were visited and specimens of Rhipicephalus (Boophilus) microplus were collected and subjected to the adult immersion test, using nine commercial acaricides in the amidine, pyrethroid and organophosphate groups. Climatic data, including monthly precipitation, were recorded. The results from the present study demonstrated that seven of the acaricides analyzed presented mean efficacy values of less than 95%, with large differences among the products tested. Nine of them exhibited satisfactory and unsatisfactory acaricide results on at least one farm. In conclusion, the farms located in the western-central region of Rio Grande do Sul, Brazil, exhibited populations of R. (Boophilus) microplus with variable degrees of susceptibility to different acaricides, thus suggesting that resistance to the active compounds exists. It is suggested that treatment protocols should be implemented at the beginning of winter and summer, using the acaricides that showed efficacy in the adult immersion test. PMID:25271453

  17. Bovine genetic resistance effects on biological traits of Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Biegelmeyer, P; Nizoli, L Q; da Silva, S S; dos Santos, T R B; Dionello, N J L; Gulias-Gomes, C C; Cardoso, F F

    2015-03-15

    This study aimed to verify the influence of bovine genetic resistance on biological traits of the Rhipicephalus (Boophilus) microplus tick. Genetic resistance or susceptibility was determined according to breeding values for tick counts, predicted using a dataset of 9007 Hereford and Braford (Hereford×Zebu) bovines naturally infested and raised under extensive production systems in southern Brazil. From a total of 974 Braford heifers born in 2008, 20 were classified as genetically tick-resistant and 20 classified as genetically tick-susceptible, and used to obtain the ticks samples used in this study. The 40 heifers were exposed to four subsequent artificial infestations with approximately 20,000 larvae at 14-day intervals. From the 19th to 23rd day of each infestation tick counts were performed on the left body side of the heifers. Engorged ticks were manually collected on the day of highest observed burden after each infestation. Tick counts on susceptible heifers were 5.5, 10.5, 11.1 and 6.9 times larger than on resistant heifers, respectively, after the first, second, third and fourth artificial infestations. In the third infestation, ticks from resistant heifers showed lower egg production index (Pticks from susceptible heifers. In the fourth infestation, ticks from susceptible group showed higher egg mass weight (Pticks from resistant heifers. Tick initial weights showed a positive association with egg production index in susceptible heifers (Presistant group (Pticks from resistant cattle. This shows that bovine genetic tick resistance, in addition to affecting the number of ticks carried by the animals, also affected the egg mass weight, egg production and nutrient indexes of ticks. The results of the present study imply that the selection of resistant animals could be used as a strategic tool for tick control in production systems, reducing infestation levels on cattle and environment. PMID:25648284

  18. Molecular characterization of Rhipicephalus (Boophilus) microplus Bm86 homologue from Haemaphysalis longicornis ticks.

    Science.gov (United States)

    Liao, Min; Zhou, Jinlin; Hatta, Takeshi; Umemiya, Rika; Miyoshi, Takeharu; Tsuji, Naotoshi; Xuan, Xuenan; Fujisaki, Kozo

    2007-05-15

    One sequence in the EST database of a midgut cDNA library prepared from semi-engorged female Haemaphysalis longicornis ticks has been found to be a homologue of the Bm86 gene of Rhipicephalus (Boophilus) microplus ticks. The full-length sequence containing a 1785 bp open reading fragment (ORF) was obtained and designated as the Hl86 gene. The predicted amino acid sequence of the Hl86 gene shows a 37% identity to the Bm86 gene. Hl86 is predicted to be a GPI-anchored membrane-bound glycoprotein with a 19-amino acid signal sequence and a 22-amino acid hydrophobic region adjacent to the carboxyl terminus. The most important feature that Hl86 has in common with Bm86 is the repeated pattern of 6 cysteine residues forming epidermal growth factor (EGF)-like domains. RT-PCR analysis showed that Hl86 mRNA transcripts are expressed in all the life cycles of H. longicornis, and the expression was found in the midgut of the adult tick. The Hl86 was expressed in Escherichia coli as a gene10 fusion protein. Mouse anti-recombinant Hl86 serum recognized an 86 kDa protein band in the midgut lysate of semi-engorged ticks in Western blot analysis and showed a strong reaction on the luminal surface of midgut cells in an indirect immunofluorescent antibody test (IFAT). Silencing of the Hl86 gene by RNAi led to a significant reduction in the engorged tick body weight. This is the first report of cloning and characterization of the Bm86 homologue in different genera and species of ixodid and argasid ticks since Bm86 was first reported in 1989. PMID:17363170

  19. Características biológicas de Boophilus microplus (acari: ixodidae a partir de infestação experimental em cão Biological characteristics of Boophilus microplus (acari: ixodidae on dog under experimental infestation

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    Marcos P. Franque

    2007-12-01

    Full Text Available Boophilus microplus (Canestrini, 1887, um parasita comum dos bovinos, tem sido observado em cães. Com objetivo de descrever características biológicas desse parasitismo, um cão foi infestado experimentalmente com 10.000 larvas de B. microplus previamente mantidas em câmara climatizada a 27 ± 1 ºC e umidade relativa superior a 80%. A média da fase parasitária foi de 24,4 ± 1,50 dias, com uma taxa de recuperação de 0,42%. Das 21 fêmeas desprendidas natural e precocemente do hospedeiro, 6 (28% ingurgitaram o suficiente (75,1 ± 30,23mg para realizar postura. O período médio de prépostura foi de 4,33 ± 1,37 dias e o período médio de postura de 9,17 ± 2,32 dias, com produção média de 18,78 ± 15,34mg de postura. O índice médio de produção de ovos observado foi de 22,38%. Estes resultados demonstraram que fêmeas de B. microplus alimentadas em cão experimentalmente infestado, completam seu ciclo biológico. A obtenção de fêmeas, capazes de realizar posturas viáveis, sugerem a possibilidade do cão atuar como hospedeiro alternativo para B. microplus, especialmente quando não há disponível outra espécie de hospedeiro preferencial.Boophilus microplus, a common parasite of cattle, has eventually reported in dogs. To describe biological features of this parasitism, one dog was experimentally infested with 10,000 larvae of B. microplus which were previously held in acclimatized camera at 27 ±1ºC and relative humidity up to 80%. The mean of parasitic phase was 24.4 ± 1.50 days, with 0.42% of recovery rate. Of 21 natural detached B. microplus females, six engorged enough (75.1 ± 30.23mg to achieve posture. The mean period of pre-posture was 4.33 ± 1.37 days and the means period of posture was 9.17 ± 2.32, producing a mean of 18.78 ± 15.34 posture weight. The mean of eggs production index observed was 22.38%. The results showed that B. microplus females fed on dogs to complete their life cycle. The females collected

  20. Susceptibility of Rhipicephalus (Boophilus) microplus to ivermectin (200, 500 and 630 μg/kg) in field studies in Brazil.

    Science.gov (United States)

    Cruz, Breno Cayeiro; Lopes, Welber Daniel Zanetti; Maciel, Willian Giquelin; Felippelli, Gustavo; Fávero, Flávia Carolina; Teixeira, Weslen Fabrício Pires; Carvalho, Rafael Silveira; Ruivo, Maycon Araújo; Colli, Marcos Henrique Alcantara; Sakamoto, Cláudio Alessandro Massamitsu; da Costa, Alvimar José; De Oliveira, Gilson Pereira

    2015-01-30

    The present study aimed to determine the susceptibility of 17 Rhipicephalus (Boophilus) microplus populations, originating in the Southeast and Southern regions of Brazil, to different ivermectin concentrations (200, 500 and 630 μg/kg), administered through subcutaneous or topical (pour-on) routes. R. (B.) microplus populations from the states of Minas Gerais (seven populations), São Paulo (seven populations) and Paraná (three populations) were chosen for the tests. The selected cattle were allocated to treatment groups on day 0, and block formation was based on the arithmetic mean of female ticks (4.5-8.0 mm long) counted on three consecutive days (-3, -2 and -1). To evaluate the therapeutic and residual efficacies of these formulations, tick counts (females ranging from 4.5 to 8.0 mm long) were performed on days 3, 7 and 14 post-treatment, and continued on a weekly basis thereafter until the end of each experiment. The results obtained throughout this study, utilizing field efficacy studies, allowed us to conclude that the resistance of R. (B.) microplus against 200 and 500 μg/kg ivermectin is widely disseminated because all tick populations that had contact with these specific concentrations were diagnosed as resistant. However, it is possible to infer that R. (B.) microplus resistance against 630 μg/kg ivermectin was also widespread, diagnosed at six of ten analyzed properties. Resistance of these ectoparasites to 630 μg/kg ivermectin is most likely emerging in three other populations of R. (B.) microplus. Strategies of resistance management need to be quickly determined to keep the selection pressure at a minimum level in Brazil. PMID:25576441

  1. In vitro acaricidal activity of ethanolic and aqueous floral extracts of Calendula officinalis against synthetic pyrethroid resistant Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Godara, R; Katoch, R; Yadav, A; Ahanger, R R; Bhutyal, A D S; Verma, P K; Katoch, M; Dutta, S; Nisa, F; Singh, N K

    2015-09-01

    Detection of resistance levels against deltamethrin and cypermethrin in Rhipicephalus (Boophilus) microplus collected from Jammu (India) was carried out using larval packet test (LPT). The results showed the presence of resistance level II and I against deltamethrin and cypermethrin, respectively. Adult immersion test (AIT) and LPT were used to evaluate the in vitro efficacy of ethanolic and aqueous floral extracts of Calendula officinalis against synthetic pyrethroid resistant adults and larvae of R. (B.) microplus. Four concentrations (1.25, 2.5, 5 and 10 %) of each extract with four replications for each concentration were used in both the bioassays. A concentration dependent mortality was observed and it was more marked with ethanolic extract. In AIT, the LC50 values for ethanolic and aqueous extracts were calculated as 9.9 and 12.9 %, respectively. The egg weight of the live ticks treated with different concentrations of the ethanolic and aqueous extracts was significantly lower than that of control ticks; consequently, the reproductive index and the percent inhibition of oviposition values of the treated ticks were reduced. The complete inhibition of hatching was recorded at 10 % of ethanolic extract. The 10 % extracts caused 100 % mortality of larvae after 24 h. In LPT, the LC50 values for ethanolic and aqueous extracts were determined to be 2.6 and 3.2 %, respectively. It can be concluded that the ethanolic extract of C. officinalis had better acaricidal properties against adults and larvae of R. (B.) microplus than the aqueous extract. PMID:26071101

  2. Toxicity of Piper aduncum L. (Piperales: Piperaceae) from the Amazon forest for the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

    Science.gov (United States)

    Silva, Wilson Castro; Martins, João Ricardo de Souza; de Souza, Hellen Emília Menezes; Heinzen, Horacio; Cesio, Maria Verônica; Mato, Mauricio; Albrecht, Francine; de Azevedo, João Lúcio; de Barros, Neiva Monteiro

    2009-10-14

    The mortality of 14-21-day-old Rhipicephalus (Boophilus) microplus larvae, and the mortality and fertility of groups of engorged adult females exposed to different concentrations of hexane, ethyl acetate and ethanol extracts of spiked pepper (Piper aduncum) were evaluated, using a completely randomized design with five treatment groups, two control groups, and two replicates for the larvae and five replicates for the adult females. Similar methodology was used to investigate the toxicity of the essential oil hydro-distillate (94.84% dillapiole) obtained from the P. aduncum crude hexane extract. The LC(50) of the hexane extract was 9.30 mg ml(-1) for larvae and the reproduction reduction ranged from 12.48% to 54.22%, while 0.1mg/ml(-1) of the essential oil induced 100% mortality in larvae. Literature reports on natural products active against R. microplus were listed and compared with the results presented here. These results indicate that P. aduncum extracts, and particularly its essential oil, are potential alternative control agents for R. microplus. PMID:19573994

  3. Efficacy of Rhipicephalus (Boophilus) microplus Bm86 against Hyalomma dromedarii and Amblyomma cajennense tick infestations in camels and cattle.

    Science.gov (United States)

    Rodríguez-Valle, Manuel; Taoufik, Amar; Valdés, Mario; Montero, Carlos; Ibrahin, Hassan; Hassan, Shawgi Mohammed; Jongejan, Frans; de la Fuente, Jose

    2012-05-14

    The recombinant Bm86-based tick vaccines have shown their efficacy for the control of cattle ticks, Rhipicephalus (Boophilus) microplus and R. annulatus infestations. However, cattle ticks often co-exist with multi-host ticks such as Hyalomma and Amblyomma species, thus requiring the control of multiple tick infestations for cattle and other hosts. Vaccination trials using a R. microplus recombinant Bm86-based vaccine were conducted in cattle and camels against Hyalomma dromedarii and in cattle against Amblyomma cajennense immature and adult ticks. The results showed an 89% reduction in the number of H. dromedarii nymphs engorging on vaccinated cattle, and a further 32% reduction in the weight of the surviving adult ticks. In vaccinated camels, a reduction of 27% and 31% of tick engorgement and egg mass weight, respectively was shown, while egg hatching was reduced by 39%. However, cattle vaccination with Bm86 did not have an effect on A. cajennense tick infestations. These results showed that Bm86 vaccines are effective against R. microplus and other tick species but improved vaccines containing new antigens are required to control multiple tick infestations. PMID:22446633

  4. Integrated control of Boophilus microplus ticks in Cuba based on vaccination with the anti-tick vaccine Gavac.

    Science.gov (United States)

    Valle, Manuel Rodriguez; Mèndez, Luis; Valdez, Mario; Redondo, Miguel; Espinosa, Carlos Montero; Vargas, Milagro; Cruz, Ricardo Lleonart; Barrios, Humberto Perez; Seoane, Guillermo; Ramirez, Emerio Serrano; Boue, Oscar; Vigil, Jorge Lodos; Machado, Héctor; Nordelo, Carlos Borroto; Piñeiro, Marisdania Joglar

    2004-01-01

    Boophilus microplus has developed resistance against a range of chemical acaricides which has stimulated the development of alternative methods such as vaccination against ticks. In Cuba, the Bm86-based recombinant vaccine Gavac has been successfully used in a number of controlled laboratory and field trials in cattle against B. microplus. In this paper, we have evaluated Gavac in a large scale field trial wherein 588,573 dairy cattle were vaccinated with the aim to reduce the number of acaricidal treatments. It was found that the number of acaricidal treatments could be reduced by 87% over a period of 8 years (1995--2003). Prior to the introduction of the vaccine, 54 clinical cases of babesiosis and six fatal cases were reported per 1000 animals. Six years later, the incidence of babesiosis was reduced to 1.9 cases per 1000 cattle and mortality reduced to 0.18 per 1000. The national consumption of acaricides in Cuba could be reduced by 82% after the implementation of the integrated anti-B. microplus control program. PMID:15651533

  5. Ação larvicida de derivados arilsulfonílicos da (+- cânfora e da (+- isopinocanfona sobre o carrapato Boophilus microplus Larvicidal action of (+-camphor and (+- isopinocamphone arilsulphonyl derivatives on Boophilus microplus cattle tick

    Directory of Open Access Journals (Sweden)

    A.C.S. Chagas

    2002-10-01

    Full Text Available Testou-se a atividade larvicida de 33 derivados arilsulfonílicos da (+-cânfora e da (+-isopinocanfona no carrapato B. microplus, na busca de princípios ativos menos tóxicos para o seu controle. Os produtos foram obtidos por clorossulfonação da (+-cânfora e da (+-isopinocanfona. Eles foram submetidos à solubilização e testados separadamente e em conjunto contra larvas de carrapato encerradas em envelopes contendo papéis impregnados e acondicionadas em estufa climatizada. A mortalidade média não atingiu 5% em todos os testes realizados, indicando que a clorossulfonação não é a rota de síntese mais adequada para a obtenção de derivados sintéticos com efeito larvicida sobre B. microplus. Os 33 produtos testados sob a forma de triagem biológica não podem ser considerados como potenciais acaricidas.It was investigated the acaricidal activity of (+- camphor and (+- isopinocamphone arilsulphonyl derivatives against Boophilus microplus cattle tick. The products were obtained through the camphor and isopinocamphone clorosulfonation. Thirty-three products were submitted to solubilization and tested alone and together, against tick larvae. Ticks were caught in filter paper envelopes impregnated with products, which were incubated under controlled conditions. The average mortality did not reach 5% in all trials, indicating that clorosulfonation is not an appropiate procedure to obtain derivatives with larvicidal effect against B. microplus. The 33 products tested in the biological screening could not be considered as potential acaricides.

  6. Transmissão transovariana de Babesia bovis em Boophilus microplus: obtenção de cepa de carrapato livre de Babesia spp. Babesia bovis transovarian transmission in Boophilus microplus: obtention of a Babesia free tick strain

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    Tânia Regina Bettin dos Santos

    2000-06-01

    Full Text Available O presente trabalho objetivou o estudo de parte do ciclo da Babesia bovis no seu hospedeiro invertebrado, o carrapato Boophilus microplus. Analisou-se a capacidade de infeccção e transmissão transovariana de B. bovis em partenóginas de B. microplus, alimentadas em bovinos portadores e enfermos por esse protozoário. No 18º dia após a infestação, coletaram-se partenóginas diretamente do corpo dos bovinos e teleóginas após o desprendimento natural, a partir do 21º dia. Todos os grupos foram incubados a 27ºC e umidade relativa superior a 70%. No 5º dia após o início da postura, realizou-se o exame de hemolinfa a fim de diagnosticar a infecção dos ínstares por B. bovis. A ausência de infecção detectada no exame de hemolinfa foi confirmada posteriormente com o teste biológico, revelando que partenóginas não transmitem B. bovis transovarianamente. Esses resultados oferecem uma técnica simplificada para a obtenção de cepas de carrapatos livres de B. bovis.In this experiment part of the life cycle of Babesia bovis in its invertebrate host, the tick Boophilus microplus was studied. In order to evaluate the capacity of infection and transmission of B. bovis were collected semi-engorged females of B. microplus fed on carrier and ill bovines. In the 18th day after infestation, semi-engorged females were collected directly from bovine bodies and after 21st day engorged females dropped on the ground. All the collected groups were incubated at 27°C and relative humidity greater than 70%. At the 5th day of oviposition the diagnosis was made by direct examination of haemolymph smears. The biological test reveled that B. bovis transovarial transmission doesn't happer in semi-engorged females. The results offer a simple techique to obtain strains of ticks free of B. bovis.

  7. Identification and characterization of Rhipicephalus (Boophilus) microplus candidate protective antigens for the control of cattle tick infestations.

    Science.gov (United States)

    Almazán, Consuelo; Lagunes, Rodolfo; Villar, Margarita; Canales, Mario; Rosario-Cruz, Rodrigo; Jongejan, Frans; de la Fuente, José

    2010-01-01

    The cattle ticks, Rhipicephalus (Boophilus) spp., affect cattle production in tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The recombinant Rhipicephalus microplus Bm86 antigen has been shown to protect cattle against tick infestations. However, variable efficacy of Bm86-based vaccines against geographic tick strains has encouraged the research for additional tick-protective antigens. Herein, we describe the analysis of R. microplus glutathione-S transferase, ubiquitin (UBQ), selenoprotein W, elongation factor-1 alpha, and subolesin (SUB) complementary DNAs (cDNAs) by RNA interference (RNAi) in R. microplus and Rhipicephalus annulatus. Candidate protective antigens were selected for vaccination experiments based on the effect of gene knockdown on tick mortality, feeding, and fertility. Two cDNA clones encoding for UBQ and SUB were used for cattle vaccination and infestation with R. microplus and R. annulatus. Control groups were immunized with recombinant Bm86 or adjuvant/saline. The highest vaccine efficacy for the control of tick infestations was obtained for Bm86. Although with low immunogenic response, the results with the SUB vaccine encourage further investigations on the use of recombinant subolesin alone or in combination with other antigens for the control of cattle tick infestations. The UBQ peptide showed low immunogenicity, and the results of the vaccination trial were inconclusive to assess the protective efficacy of this antigen. These experiments showed that RNAi could be used for the selection of candidate tick-protective antigens. However, vaccination trials are necessary to evaluate the effect of recombinant antigens in the control of tick infestations, a process that requires efficient recombinant protein production and formulation systems. PMID:19943063

  8. Detección de resistencia a los acaricidas en la garrapata del ganado Boophilus microplus mediante análisis de zimogramas (Acaricide resistance detection in the cattle tick Boophilus microplus by zymograms analysis.

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    Miranda, Miranda, Estefan

    2005-11-01

    Full Text Available La identificación de resistencia a los productos acaricidas en la garrapata B. microplus, se hace mediante un complicado bioensayo, que requiere garrapatas de referencia y de campo cultivadas sobre bovinos vivos y restringidos durante semanas. Con el fin de evaluar una posible alternativa diagnóstica, se hicieron ensayos enzimáticos en geles de poliacrilamida-SDS, usando extractos de larvas de garrapatas provenientes de cuatro cepas de referencia con diferentes niveles de resistencia y susceptibilidad a productos acaricidas. Los ensayos que se diseñaron para detectar las enzimas esterasa, fosfodiesterasa, glutatión peroxidasa y catalasa, fueron procesados como zimogramas en imágenes digitalizadas, a partir de las cuales se obtuvieron sus respectivos densitogramas, valorando las movilidades electroforéticas relativas (Rf, así como las diferentes masas moleculares (MM en miles de Daltons (kDa y actividades enzimáticas específicas (AEE. Se identificó una elevada actividad de esterasa en posición Rf 0.52 con una MM de 47 kDa en las cepas resistentes, con un incremento en AEE del 317 % cuando se compara con las garrapatas susceptibles a los acaricidas. También se identificó una fosfodiesterasa en Rf. 0.1 con MM de 130 kDa presente en las cepas resistentes, con un incremento de AEE del 340% con respecto al nivel basal de la cepa susceptible. Se concluyó que estos ensayos enzimáticos pueden ser utilizados como indicadores de resistencia a los acaricidas en poblaciones de garrapatas aisladas de campo, constituyendo un procedimiento rápido, eficaz y económico, como alternativa al complicado bioensayo actualmente utilizado. Acaricide resistance detection in the cattle tick Boophilus microplus, is achieved by a complex bioassay which requires reference strains of ticks as well as field isolated ticks, cultured on living cattle restrained for weeks. In order to assess an alternate diagnostics procedure, enzymatic assays were performed on

  9. Efficacy of 11 Brazilian essential oils on lethality of the cattle tick Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Chagas, Ana Carolina de Souza; Oliveira, Márcia Cristina de Sena; Giglioti, Rodrigo; Santana, Raul Costa Mascarenhas; Bizzo, Humberto Ribeiro; Gama, Paola Ervatti; Chaves, Francisco Celio Maia

    2016-04-01

    Herbal extracts have been investigated as an alternative for parasite control, aiming to slow the development of resistance and to obtain low-cost biodegradable parasiticides. The goal of this study was to evaluate the efficacy, in vitro, of 11 essential oils from Brazil on reproductive efficiency and lethality of the cattle tick Rhipicephalus (Boophilus) microplus. The effects of oils extracted from Curcuma longa, Zingiber officinale, Lippia alba, Lippia gracilis, Lippia origanoides, Lippia sidoides, Mentha arvensis, Mentha piperita, Croton cajucara (white and red), and Croton sacaquinha on ticks were investigated by the Immersion Test with Engorged Females (ITEF) and the modified Larval Packet Test (LPT). Distilled water and 2% Tween 80 were used as control treatments. Chemical analysis of the oils was done with gas chromatography coupled with mass spectrometry. Analysis of the in vitro tests using Probit (SAS program) allowed the calculation of lethal concentrations (LCs). Lower reproductive efficiency indexes and higher efficacy percentages in the ITEF were obtained with the oils extracted from C. longa (24 and 71%, respectively) and M. arvensis oils (27 and 73%, respectively). Lower LC50 was reached with C. longa (10.24 mg/mL), L. alba (10.78 mg/mL), M. arvensis (22.31 mg/mL), L. sidoides (27.67 mg/mL), and C. sacaquinha (29.88 mg/mL) oils. In the LPT, species from Zingiberaceae and Verbenaceae families caused 100% lethality at 25 mg/mL, except for L. sidoides. The most effective oils were from C. longa, L. gracilis, L. origanoides, L. alba, and Z. officinale. The LC50 and LC90 were, respectively: 0.54 and 1.80 mg/mL, 3.21 and 7.03 mg/mL, 3.10 and 8.44 mg/mL, 5.85 and 11.14 mg/mL, and 7.75 and 13.62 mg/mL. The efficacy was directly related to the major components in each essential oil, and the oils derived from Croton genus presented the worst performance, suggesting the absence of synergistic effect among its compounds. Since C. longa, containing 62

  10. Gene silencing of the tick protective antigens, Bm86, Bm91 and subolesin, in the one-host tick Boophilus microplus by RNA interference

    OpenAIRE

    Nijhof, A. M.; Taoufik, A.; de la Fuente, M.R.; Kocan, K M; de Vries, E; Jongejan, F

    2007-01-01

    The use of RNA interference (RNAi) to assess gene function has been demonstrated in several three-host tick species but adaptation of RNAi to the one-host tick, Boophilus microplus, has not been reported. We evaluated the application of RNAi in B. microplus and the effect of gene silencing on three tick-protective antigens: Bm86, Bm91 and subolesin. Gene-specific double-stranded (dsRNA) was injected into two tick stages, freshly molted unfed and engorged females, and specific gene silencing w...

  11. Use of biodegradable PLGA microspheres as a slow release delivery system for the Boophilus microplus synthetic vaccine SBm7462.

    Science.gov (United States)

    Sales-Junior, P A; Guzman, F; Vargas, M I; Sossai, S; Patarroyo V, A M; González, C Z L; Patarroyo, J H

    2005-09-15

    The synthetic anti-Boophilus microplus vaccine SBm7462 derived from the tick intestinal protein, Bm86, induced a protective immune response when emulsified in saponin and used in cattle. Using a mice model, and with the objective of improving the vaccine by continual peptide release, it was encapsulated in PLGA 50:50 microspheres and inoculated in BALB/c mice to assess the immunological response by detection of anti-peptide IgGs. Comparative studies were made with the peptide emulsified in saponin and with another synthetic vaccine, and the microsphere/peptide was characterized for efficiency of encapsulation, in vitro release profile, morphology, size, peptide integrity after encapsulation and stability in different pHs. The findings showed that saponin enhances a better immune response from SBm7462 and that the PLGA 50:50 microspheres are suitable for use with this peptide. PMID:16002149

  12. Comparative vaccination of cattle against Boophilus microplus with recombinant antigen Bm86 alone or in combination with recombinant Bm91.

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    Willadsen, P; Smith, D; Cobon, G; McKenna, R V

    1996-05-01

    Cattle were vaccinated either with a single recombinant tick antigen, Bm86 or with a combination of two recombinant antigens, Bm86 and Bm91 from the tick Boophilus microplus. In three experiments, the responses of cattle to subsequent challenge with the tick were assessed. The addition of the Bm91 antigen enhanced the efficacy of the vaccination over that with Bm86 alone to a statistically significant degree. Moreover, co-vaccination with two antigens did not impair the response of cattle to the Bm86 antigen. Finally, responses of individual cattle to the two antigens were independent. All of these results may be relevant to the increase in efficacy expected from a dual antigen vaccine. PMID:9229376

  13. Rhipicephalus (Boophilus microplus (Acari: Ixodidae as a parasite of pampas deer (Ozoctoceros bezoarticus and cattle in Brazil's Central Pantanal Rhipicephalus (Boophilus microplus como parasita de veado-campeiro (Ozoctoceros bezoarticus e do gado bovino no Pantanal Central do Brasil

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    Paulo Henrique Duarte Cançado

    2009-03-01

    Full Text Available In the Pantanal, domestic and wild animals share the same habitats; their parasites and environment interact in a complex and dynamic way. The Rhipicephalus (Boophilus microplus is the most important cattle tick in Brazil. In the past two decades, some traditional management practices are being replaced with the aim of intensifying cattle production. Forested areas are being replaced by exotic pasture and ranch owners are replacing Nelore for European breeds. The pampas deer (Ozoctoceros bezoarticus is a medium-sized cervid that occurs in grasslands of South America. Between December 2005 and January 2007, we captured and collected ticks from 15 pampas deer and 172 bovines. The abundance, intensity, and prevalence of ticks found in cattle were lower than those in pampas deer (p No Pantanal Brasileiro, onde animais domésticos e selvagens compartilham os mesmos habitats; hospedeiros, parasitas e ambientes encontram-se em interação complexa e dinâmica. Rhipicephalus (Boophilus microplus é o carrapato bovino mais importante no Brasil. Nas últimas duas décadas práticas de manejo vem sendo substituídas com objetivo de aumentar a produtividade. Áreas de florestas estão sendo substituídas por pastagens exóticas e os produtores começam a utilizar raças européias no lugar do Nelore. O veado-campeiro é um cervídeo que ocorre em áreas de campo na América do sul. Entre dezembro de 2005 e janeiro de 2007, foram coletados carrapatos de 20 veados-campeiros e 172 bovinos. Os valores de abundância, intensidade parasitária e prevalência de carrapatos no gado foram menores que os valores encontrados no veado-campeiro (p < 0,05, indicando que o veado-campeiro é mais susceptível que o bovino. O elevado número de fêmeas ingurgitadas coletadas, sua capacidade de ovipor e o percentual de eclosão indicam que a população veado-campeiro na região de estudo é suficiente para manter o R. (B. microplus, desta maneira participando na

  14. Acaricide activity of leaves extracts of Sambucus australis Schltdl. (Caprifoliaceae at 2% on engorged females of Rhipicephalus (Boophilus microplus

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    Felipe da Silva Krawczak

    2011-12-01

    Full Text Available Parasite infections caused by Rhipicephalus (Boophilus microplus are responsible for the most of economic losses in producing-cattle countries in tropical and subtropical areas. Indiscriminate uses of chemical acaricides have contributed with the appearance of tick resistance to many drugs available in the marketplace, and it is a serious problem in the tick control. Flowers of Sambucus australis (South America, called "sabugueiro-from-Brazil", are used on infusions or decoctions forms in the folk medicine with diuretic, antipyretic, anti-inflammatory, and laxative purpose, also employed for treating respiratory diseases in human. The main goal of this study was to evaluate in vitro potential of S. australis leaves extracts as an acaricide agent. Ethanol extract at 70% has been dehydrated and a fraction was suspended in 70% ethanol or in distillated water at final concentration of 2% (0.2mg-1. Using the immersion test of engorged females the efficiency results were obtained in 34% and 66% with the leaves extract diluted in water and 70% ethanol, respectively. This study is the first report on acaricidal activity of S. australis against cattle tick. Further studies to determine the active metabolites in different stages of S. australis could aid to identify suitable extracts to be tested in the R. (B. microplus control.

  15. Identification of potential plant extracts for anti-tick activity against acaricide resistant cattle ticks, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

    Science.gov (United States)

    Ghosh, Srikanta; Tiwari, Shashi Shankar; Kumar, Bhanu; Srivastava, Sharad; Sharma, Anil Kumar; Kumar, Sachin; Bandyopadhyay, A; Julliet, Sanis; Kumar, Rajesh; Rawat, A K S

    2015-05-01

    To develop an eco-friendly tick control method, seven plant extracts were prepared using 50 and 95% ethanol and evaluated for acaricidal activity against cattle tick, Rhipicephalus (Boophilus) microplus. The adult immersion test was adopted for testing different extracts. Based on 72 h screening criterion, 95% ethanolic extracts of Datura metel fruits and Argemone mexicana whole plant were found effective showing more than 50% mortality of treated ticks. The 95% ethanolic extracts of D. metel fruits and A. mexicana whole plant exhibited acaricidal and reproductive inhibitory effects on treated ticks. The LC90 values of D. metel and A. mexicana extracts were determined as 7.13 and 11.3%, respectively. However, although both the extracts were found efficacious against deltamethrin-resistant IVRI-4 and multi-acaricide resistant IVRI-5 lines of R. (B.) microplus, they caused less mortality than treated ticks of the reference IVRI-I line. Phytochemical studies indicated the presence of alkaloids and glucosides in D. metel fruits and alkaloids, terpenoids, flavonoids and phenolics in A. mexicana whole plant extracts. The results indicated that these botanicals may play an important role in reducing the use of chemicals for tick control and possibly to manage resistant tick population in environment friendly manner. PMID:25717008

  16. Detecting resistance to organophosphates and carbamates in the cattle tick Boophilus microplus, with a propoxur-based biochemical test.

    Science.gov (United States)

    Baxter, G D; Green, P; Stuttgen, M; Barker, S C

    1999-11-01

    Rapid and sensitive detection of resistance to insecticides in arthropods is needed. In the cattle tick. Boophilus microplus, resistance to a variety of acaricides is widespread. The most commonly used assay for resistance, the larval packet test, takes at least two, but generally six weeks for a one-host tick like B. microplus to complete and may take up to three months to complete for three-host ticks. Here we describe a test for resistance to organophosphate acaricides that can be used on larvae and adult ticks which takes less than 24 hours. The test measures the difference in acetylcholinesterase (AChE) activity in homogenates of ticks in the presence and absence of propoxur, a carbamate acaricide. We found clear discrimination of organophosphate-susceptible and organophosphate-resistant adults with 100 microM propoxur. AChE from susceptible ticks had almost no activity at this concentration of propoxur whereas AChE from resistant ticks had 67% of its potential activity. AChE from heterozygote ticks could also be distinguished from AChE from homozygous-susceptible and homozygous-resistant ticks. This is the first biochemical test for resistance to an acaricide. Rapid, sensitive tests like ours will allow resistance to organophosphates to be detected soon after it develops in the field, thus, the spread of resistance might be slowed and the useful life of acaricides extended.

  17. Immune response in mice and cattle after immunization with a Boophilus microplus DNA vaccine containing bm86 gene.

    Science.gov (United States)

    Ruiz, Lina María; Orduz, Sergio; López, Elkin D; Guzmán, Fanny; Patarroyo, Manuel E; Armengol, Gemma

    2007-03-15

    Plasmid pBMC2 encoding antigen Bm86 from a Colombian strain of cattle tick Boophilus microplus, was used for DNA-mediated immunization of BALB/c mice, employing doses of 10 and 50microg, delivered by intradermic and intramuscular routes. Anti-Bm86 antibody levels were significantly higher compared to control mice treated with PBS. In the evaluation of immunoglobulin isotypes, significant levels of IgG2a and IgG2b were observed in mice immunized with 50microg of pBMC2. Measurement of interleukine (IL) levels (IL-4, IL-5, IL-12(p40)) and interferon-gamma (IFN-gamma) in the sera of mice immunized with pBMC2 indicated high levels of IL-4 and IL-5, although there were also significant levels of IFN-gamma. Mice immunized with pBMC2 showed antigen-specific stimulation of splenocytes according to the incorporation of bromodeoxyuridine and IFN-gamma secretion. In all trials, mice injected intramuscularly with 50microg of pBMC2 presented the highest immune response. Moreover, cattle immunized with this DNA vaccine showed antibody production significantly different to the negative control. In conclusion, these results suggest the potential of DNA immunization with pBMC2 to induce humoral and cellular immune responses against B. microplus. PMID:17055651

  18. Expression of recombinant Rhipicephalus (Boophilus microplus, R. annulatus and R. decoloratus Bm86 orthologs as secreted proteins in Pichia pastoris

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    Jongejan Frans

    2008-02-01

    Full Text Available Abstract Background Rhipicephalus (Boophilus spp. ticks economically impact on cattle production in Africa and other tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The R. microplus Bm86 protective antigen has been produced by recombinant DNA technology and shown to protect cattle against tick infestations. Results In this study, the genes for Bm86 (R. microplus, Ba86 (R. annulatus and Bd86 (R. decoloratus were cloned and characterized from African or Asian tick strains and the recombinant proteins were secreted and purified from P. pastoris. The secretion of recombinant Bm86 ortholog proteins in P. pastoris allowed for a simple purification process rendering a final product with high recovery (35–42% and purity (80–85% and likely to result in a more reproducible conformation closely resembling the native protein. Rabbit immunization experiments with recombinant proteins showed immune cross-reactivity between Bm86 ortholog proteins. Conclusion These experiments support the development and testing of vaccines containing recombinant Bm86, Ba86 and Bd86 secreted in P. pastoris for the control of tick infestations in Africa.

  19. Sequence variations in the Boophilus microplus Bm86 locus and implications for immunoprotection in cattle vaccinated with this antigen.

    Science.gov (United States)

    García-García, J C; Gonzalez, I L; González, D M; Valdés, M; Méndez, L; Lamberti, J; D'Agostino, B; Citroni, D; Fragoso, H; Ortiz, M; Rodríguez, M; de la Fuente, J

    1999-11-01

    Cattle tick infestations constitute a major problem for the cattle industry in tropical and subtropical regions of the world. Traditional control methods have been only partially successful, hampered by the selection of chemical-resistant tick populations. The Boophilus microplus Bm86 protein was isolated from tick gut epithelial cells and shown to induce a protective response against tick infestations in vaccinated cattle. Vaccine preparations including the recombinant Bm86 are used to control cattle tick infestations in the field as an alternative measure to reduce the losses produced by this ectoparasite. The principle for the immunological control of tick infestations relies on a polyclonal antibody response against the target antigen and, therefore, should be difficult to select for tick-resistant populations. However, sequence variations in the Bm86 locus, among other factors, could affect the effectiveness of Bm86-containing vaccines. In the present study we have addressed this issue, employing data obtained with B. microplus strains from Australia, Mexico, Cuba, Argentina and Venezuela. The results showed a tendency in the inverse correlation between the efficacy of the vaccination with Bm86 and the sequence variations in the Bm86 locus (R2 = 0.7). The mutation fixation index in the Bm86 locus was calculated and shown to be between 0.02 and 0.1 amino acids per year. Possible implications of these findings for the immunoprotection of cattle against tick infestations employing the Bm86 antigen are discussed. PMID:10668863

  20. Integrated control of acaricide-resistant Boophilus microplus populations on grazing cattle in Mexico using vaccination with Gavac and amidine treatments.

    Science.gov (United States)

    Redondo, M; Fragoso, H; Ortíz, M; Montero, C; Lona, J; Medellín, J A; Fría, R; Hernández, V; Franco, R; Machado, H; Rodríguez, M; de la Fuente, J

    1999-10-01

    Throughout most of the twentieth century, tick infestations on cattle have been controlled with chemical acaricides, typically administered by dipping or spraying. This approach can cause environmental and residue problems and has created a high incidence of acaricide resistance within tick populations in the field. Recently we developed a vaccine against Boophilus microplus employing a recombinant Bm86 antigen preparation (Gavac), (Heber Biotec S.A., Havana, Cuba) which has been shown to induce a protective response in vaccinated animals. Here we show for the first time under field conditions a near 100% control of B. microplus populations resistant to pyrethroids and organophosphates, by an integrated system employing vaccination with Gavac and amidine treatments. This method effectively controls tick infestations while reducing the number of chemical acaricide treatments and consequently the rise of B. microplus populations resistant to chemical acaricides. PMID:10581714

  1. Resistance to cypermethrin and amitraz in Rhipicephalus (Boophilus microplus on the Santa Catarina Plateau, Brazil Situação da resistência do Rhipicephalus (Boophilus microplus à cipermetrina e amitraz no Planalto Catarinense, Brasil

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    Luana Paula Haubold Neis Veiga

    2012-06-01

    Full Text Available With the objective of evaluating Rhipicephalus (Boophilus microplus resistance to cipermetrina and amitraz, were collected engorged tick females from cattle on 20 farms on the Santa Catarina Plateau, in southern Brazil, between January of 2004 and May of 2006. Were also received 20 groups of engorged R. (B. microplus females, collected by cattle farmers requesting acaricidal efficacy (AE testing. Were performed in vitro tests, which consisted of immersing engorged females in cypermethrin (0.015% and in amitraz (0.025%. An AE >95% was considered indicative of effectiveness. Of the 20 collected groups, 18 (90% showed cypermethrin resistance and 1 (5% showed amitraz resistance. Of the 20 received groups, 19 (95% showed cypermethrin resistance and 2 (10% showed amitraz resistance. The AE of cypermethrin was found to be >95%, 85-94%, and 55-64%, respectively, in 4 (57.1%, 2 (28.6%, and 1 (14.3% of 7 reference groups, collected in the 1997-2001 period. The AE of amitraz was >95% in all of those groups. Among the groups of specimens received for analysis in that period, the AE of amitraz was >95% in 6 (85.71% and 75-84% in 1 (14.28%. R. (B. microplus resistance to acaricides is increasing on the Santa Catarina Plateau.Com os objetivos de avaliar a resistência do Rhipicephalus (Boophilus microplus à cipermetrina e ao amitraz no Planalto Catarinense, no período de janeiro de 2004 a maio de 2006, foram coletadas teleóginas em bovinos de 20 propriedades onde os produtores autorizaram a coleta (amostras por conveniência e recebidas teleóginas de mais 20 propriedades com objetivo de diagnóstico de eficácia. Os testes in vitro foram realizados por imersão de teleóginas em cipermetrina (0,015% e amitraz (0,025%. Considerando a eficácia igual ou superior a 95%, das 20 propriedades amostradas, 18 (90% apresentaram resistência à cipermetrina e uma (5% ao amitraz. Das 20 propriedades com teleóginas para diagnóstico, 19 (95% apresentaram resist

  2. Rhipicephalus (Boophilus microplus: expression and characterization of Bm86-CG in Pichia pastoris Rhipicephalus (Boophilus microplus: expressão e caracterização da Bm86-CG em Pichia pastoris

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    Rodrigo Casquero Cunha

    2011-06-01

    Full Text Available The cattle tick Rhipicephalus (Boophilus microplus is responsible for great economic losses. It is mainly controlled chemically, with limitations regarding development of resistance to the chemicals. Vaccines may help control this parasite, thereby reducing tick pesticide use. In this light, we performed subcloning of the gene of the protein Bm86-GC, the homologue protein that currently forms the basis of vaccines (GavacTM and TickGardPLUS that have been developed against cattle ticks. The subcloning was done in the pPIC9 expression vector, for transformation in the yeast Pichia pastoris. This protein was characterized by expression of the recombinant Mut+ strain, which expressed greater quantities of protein. The expressed protein (rBm86-CG was recognized in the Western-blot assay using anti-Gavac, anti-TickGard, anti-larval extract and anti-rBm86-CG polyclonal sera. The serum produced in cattle vaccinated with the antigen CG rBm86 presented high antibody titers and recognized the native protein. The rBm86-GC has potential relevance as an immunogen for vaccine formulation against cattle ticks.O carrapato-do-boi Rhipicephalus (Boophilus microplus é responsável por grandes perdas econômicas. Seu controle é principalmente químico e apresenta limitações quanto ao desenvolvimento de resistência aos princípios ativos. As vacinas podem auxiliar no controle deste parasita diminuindo as aplicações de carrapaticidas. Considerando isso, foi realizada a subclonagem do gene da proteína Bm86-CG, proteína homologa a que atualmente é a base das vacinas desenvolvidas (GavacTM e TickGardPLUS contra o carrapato-do-boi, no vetor de expressão pPIC9, para ser transformado em levedura, Pichia pastoris. Esta proteína foi caracterizada pela expressão da cepa recombinante Mut+ que expressou maior quantidade de proteína. A proteína expressa, rBm86-CG, foi reconhecida no ensaio de Western-blot pelos soros policlonais anti-Gavac, anti-TickGard, anti

  3. Extratos de plantas no controle de Rhipicephalus (Boophilus microplus (Canestrini, 1887 (Acari: Ixodidae em laboratório Plant extracts in control of Rhipicephalus (Boophilus microplus (Canestrini, 1887 (Acari: Ixodidae in laboratory

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    Sônia Maria Forti Broglio-Micheletti

    2009-12-01

    Full Text Available Extratos vegetais foram estudados com o objetivo de avaliar suas eficiências no controle de Rhipicephalus (Boophilus microplus (Canestrini, 1887 em laboratório. Fêmeas ingurgitadas de carrapato foram coletadas de bovinos e mantidas em placas de Petri. Foram utilizados extratos orgânicos alcoólicos 2% (peso/volume de sementes de Annona muricata L. (Annonaceae (graviola; flores de Syzygium malaccensis (L. (Myrtaceae (jambo; folhas de Cymbopogon citratus (DC. Stapf (Poaceae (capim-santo; folhas de Azadirachta indica A. Juss (Meliaceae (nim; e extrato hexânico na mesma concentração de A. indica (sementes. Os grupos-controle foram compostos por fêmeas sem tratamento e fêmeas tratadas com água destilada e esterilizada e dimetilsulfóxido (DMSO a uma concentração de 1%. O extrato de A. muricata apresentou o maior poder acaricida, com eficácia de 100%, seguido dos extratos de S. malaccensis (75 e 59,24% e A. indica (65 e 38,49%. Houve 100% de redução na eclosão das larvas quando se utilizou o extrato de sementes de A. muricata.Plant extracts were studied to evaluate its efficiency in the control of Rhipicephalus (Boophilus microplus (Canestrini, 1887 in laboratory. Engorged female ticks were collected from the cattle, kept in Petri dishes. Organic alcoholic extracts 2% (weight/volume were used: seeds of Annona muricata L. (Annonaceae (soursop; flowers of Syzygium malaccensis (L. (Myrtaceae (iamb, leaves of Cymbopogon citratus (DC. Stapf (Poaceae (holy grass, leaves of Azadirachta indica A. Juss (Meliaceae (neem and hexane extract 2% (weight/volume of A. indica (seeds. The control groups consisted of untreated females and females treated with distilled water and sterile and dimethylsulfoxide (DMSO a concentration of 1%. The extract of A. muricata (seed had the highest mortality with acaricide activity and 100% efficacy followed by extracts of S. malaccensis (75 and 59.24% and A. indica (65 and 38.49%. The seed extract of A. muricata

  4. Use of biotherapic in the control of the natural infestation by Boophilus microplus: pilot study Uso de bioterápico en el control de la infestación natural por Boophilus microplus: estudio piloto

    OpenAIRE

    Laerte Francisco Filippsen; José Luiz Moletta; Nilceu Lemos Silva; Alessandro Pelegrine Minho

    2008-01-01

    In the control of tick-borne disease (TBD), resistance to chemical products has been reported and a concern with the preservation of the environment requires alternative procedures to control infestation by Boophilus microplus worldwide. The use of biotherapic preparations is one of such alternatives. The aim of this study was to evaluate the effects of a biotherapic mixture including B. microplus in naturally infested cattle. 27 animals were divided in 3 groups (n=9): I – control, re...

  5. Gene expression in the skin of Bos taurus and Bos indicus cattle infested with the cattle tick, Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Piper, Emily K; Jackson, Louise A; Bagnall, Neil H; Kongsuwan, Kritaya K; Lew, Ala E; Jonsson, Nicholas N

    2008-11-15

    The cattle tick Rhipicephalus microplus (formerly Boophilus microplus) is responsible for severe production losses to the cattle industry worldwide. It has long been known that different breeds of cattle can resist tick infestation to varying degrees; however, the mechanisms by which resistant cattle prevent heavy infestation are largely unknown. The aim of this study was to determine whether gene expression varied significantly between skin sampling sites (neck, chest and tail region), and whether changes in gene expression could be detected in samples taken at tick attachment sites (tick attached to skin sample) compared with samples taken from non-attachment sites (no tick attachment). We present here the results of an experiment examining the expression of a panel of forty-four genes in skin sections taken from Bos indicus (Brahman) cattle of known high resistance, and Bos taurus (Holstein-Friesian) cattle of known low resistance to the cattle tick. The forty-four genes chosen for this study included genes known to be involved in several immune processes, some structural genes, and some genes previously suggested to be of importance in tick resistance by other researchers. The expression of fifteen gene transcripts increased significantly in Holstein-Friesian skin samples at tick attachment sites. The higher expression of many genes involved in innate inflammatory processes in the Holstein-Friesian animals at tick attachment sites suggests this breed is exhibiting a non-directed pathological response to infestation. Of the forty-four genes analysed, no transcripts were detected in higher abundance at tick attachment sites in the Brahman cattle compared with similar samples from the Holstein-Friesian group, nor difference between attachment site and non-attachment site samples within the Brahman group. The results presented here suggest that the means by which these two cattle breeds respond to tick infestation differ and warrant further investigation. PMID

  6. Comparative microarray analysis of Rhipicephalus (Boophilus microplus expression profiles of larvae pre-attachment and feeding adult female stages on Bos indicus and Bos taurus cattle

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    Gondro Cedric

    2010-07-01

    Full Text Available Abstract Background Rhipicephalus (Boophilus microplus is an obligate blood feeder which is host specific to cattle. Existing knowledge pertaining to the host or host breed effects on tick transcript expression profiles during the tick - host interaction is poor. Results Global analysis of gene expression changes in whole R. microplus ticks during larval, pre-attachment and early adult stages feeding on Bos indicus and Bos taurus cattle were compared using gene expression microarray analysis. Among the 13,601 R. microplus transcripts from BmiGI Version 2 we identified 297 high and 17 low expressed transcripts that were significantly differentially expressed between R. microplus feeding on tick resistant cattle [Bos indicus (Brahman] compared to R. microplus feeding on tick susceptible cattle [Bos taurus (Holstein-Friesian] (p ≤ 0.001. These include genes encoding enzymes involved in primary metabolism, and genes related to stress, defence, cell wall modification, cellular signaling, receptor, and cuticle formation. Microarrays were validated by qRT-PCR analysis of selected transcripts using three housekeeping genes as normalization controls. Conclusion The analysis of all tick stages under survey suggested a coordinated regulation of defence proteins, proteases and protease inhibitors to achieve successful attachment and survival of R. microplus on different host breeds, particularly Bos indicus cattle. R. microplus ticks demonstrate different transcript expression patterns when they encounter tick resistant and susceptible breeds of cattle. In this study we provide the first transcriptome evidence demonstrating the influence of tick resistant and susceptible cattle breeds on transcript expression patterns and the molecular physiology of ticks during host attachment and feeding. The microarray data used in this analysis have been submitted to NCBI GEO database under accession number GSE20605 http://www.ncbi

  7. The Rhipicephalus (Boophilus microplus Bm86 gene plays a critical role in the fitness of ticks fed on cattle during acute Babesia bovis infection

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    Knowles Donald P

    2010-11-01

    Full Text Available Abstract Background Rhipicephalus (Boophilus microplus is an economically important tick of cattle involved in the transmission of Babesia bovis, the etiological agent of bovine babesiosis. Commercial anti-tick vaccines based on the R. microplus Bm86 glycoprotein have shown some effect in controlling tick infestation; however their efficacy as a stand-alone solution for tick control has been questioned. Understanding the role of the Bm86 gene product in tick biology is critical to identifying additional methods to utilize Bm86 to reduce R. microplus infestation and babesia transmission. Additionally, the role played by Bm86 in R. microplus fitness during B. bovis infection is unknown. Results Here we describe in two independent experiments that RNA interference-mediated silencing of Bm86 decreased the fitness of R. microplus females fed on cattle during acute B. bovis infection. Notably, Bm86 silencing decreased the number and survival of engorged females, and decreased the weight of egg masses. However, gene silencing had no significant effect on the efficiency of transovarial transmission of B. bovis from surviving female ticks to their larval offspring. The results also show that Bm86 is expressed, in addition to gut cells, in larvae, nymphs, adult males and ovaries of partially engorged adult R. microplus females, and its expression was significantly down-regulated in ovaries of ticks fed on B. bovis-infected cattle. Conclusion The R. microplus Bm86 gene plays a critical role during tick feeding and after repletion during blood digestion in ticks fed on cattle during acute B. bovis infection. Therefore, the data indirectly support the rationale for using Bm86-based vaccines, perhaps in combination with acaricides, to control tick infestation particularly in B. bovis endemic areas.

  8. Rhipicephalus (Boophilus) microplus strain Deutsch, whole genome shotgun sequencing project first submission of genome sequence

    Science.gov (United States)

    The size and repetitive nature of the Rhipicephalus microplus genome makes obtaining a full genome sequence difficult. Cot filtration/selection techniques were used to reduce the repetitive fraction of the tick genome and enrich for the fraction of DNA with gene-containing regions. The Cot-selected ...

  9. CattleTickBase: An integrated Internet-based bioinformatics resource for Rhipicephalus (Boophilus) microplus

    Science.gov (United States)

    The Rhipicephalus microplus genome is large and complex in structure, making a genome sequence difficult to assemble and costly to resource the required bioinformatics. In light of this, a consortium of international collaborators was formed to pool resources to begin sequencing this genome. We have...

  10. Diagnosis of amitraz resistance in Brazilian populations of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) with larval immersion test.

    Science.gov (United States)

    Mendes, Elisa Cimitan; Mendes, Márcia Cristina; Sato, Mário Eidi

    2013-11-01

    Among the ectoparasites of cattle, Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae) remains a major cause of economic losses to livestock. The chemical control with acaricides is still the most efficient method available to control ticks. The aims of this study were to diagnose resistance to amitraz in 16 tick populations from the States of São Paulo (14) and Paraná (2), using the larval immersion technique (LIT), and evaluate the effect of synergists [piperonyl butoxide (PBO), diethyl maleate (DEM), triphenyl phosphate (TPP)] on amitraz resistant and susceptible strains of cattle tick. Most of the evaluated populations (68.7 %) showed to be resistant to amitraz, with resistance ratios ranging from 2.14 to 132. The results suggest that the test procedure by LIT is sensitive and adequate for detection and monitoring of amitraz resistance in cattle tick. No synergistic effect was observed for the synergists PBO, DEM and TPP, on the amitraz resistant (Poa) strain of cattle tick, indicating that increased detoxification metabolism was not involved in this resistance. PMID:23620418

  11. Evaluation of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) resistance to different acaricide formulations using samples from Brazilian properties.

    Science.gov (United States)

    Higa, Leandro de Oliveira Souza; Garcia, Marcos Valério; Barros, Jacqueline Cavalcante; Koller, Wilson Werner; Andreotti, Renato

    2016-06-01

    The Rhipicephalus (Boophilus) microplus tick is responsible for considerable economic losses in Brazil, causing leather damage, weight loss and reduced milk production in cattle and results in the transmission of pathogens. Currently, the main method for controlling this tick is using acaricides, but their indiscriminate use is one of the major causes of resistance dissemination. In this study, the adult immersion test (AIT) was used to evaluate resistance in ticks from 28 properties located in five different states (Mato Grosso do Sul, Mato Grosso, Ceará, São Paulo, e Minas Gerais) and the Distrito Federal (DF) of Brazil. The resistance was found in 47.64% of the repetitions demonstrating an efficacy of less than 90% in various locations throughout the country. The larvae packet test was used to evaluate samples from ten properties in four states (Mato Grosso do Sul, Mato Grosso, Minas Gerais and Espírito Santo). Spray products belonging to the main classes of acaricides, including combination formulations, were used in both types of test. New cases of resistance were found on properties within the states of Ceará, Espírito Santo and Mato Grosso, where such resistance was not previously reported. PMID:27334816

  12. Evaluation of Rhipicephalus (Boophilus microplus (Acari: Ixodidae resistance to different acaricide formulations using samples from Brazilian properties

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    Leandro de Oliveira Souza Higa

    2016-01-01

    Full Text Available Abstract The Rhipicephalus (Boophilus microplus tick is responsible for considerable economic losses in Brazil, causing leather damage, weight loss and reduced milk production in cattle and results in the transmission of pathogens. Currently, the main method for controlling this tick is using acaricides, but their indiscriminate use is one of the major causes of resistance dissemination. In this study, the adult immersion test (AIT was used to evaluate resistance in ticks from 28 properties located in five different states (Mato Grosso do Sul, Mato Grosso, Ceará, São Paulo, e Minas Gerais and the Distrito Federal (DF of Brazil. The resistance was found in 47.64% of the repetitions demonstrating an efficacy of less than 90% in various locations throughout the country. The larvae packet test was used to evaluate samples from ten properties in four states (Mato Grosso do Sul, Mato Grosso, Minas Gerais and Espírito Santo. Spray products belonging to the main classes of acaricides, including combination formulations, were used in both types of test. New cases of resistance were found on properties within the states of Ceará, Espírito Santo and Mato Grosso, where such resistance was not previously reported.

  13. IN VITRO EFFICACY OF COMMERCIAL ACARICIDES INDICATE RESISTANT POPULATIONS OF RHIPICEPHALUS (BOOPHILUS MICROPLUS IN NORTHERN REGION OF MATO GROSSO

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    C. Eckstein

    2016-02-01

    Full Text Available Ticks are responsible for high economic and production losses on cattle production, and the use of acaricides is the main form of control applied. In recent decades, the resistance of ticks to acaricides was exacerbated by incorrect use of products, compromising the effectiveness of treatments. This study aimed to determine in vitro effectiveness of commercial acaricides in six populations of Rhipicephalus (Boophilus microplus in northern region of Mato Grosso. On average 100 engorged females were collected from each herd, which were selected and separated into homogeneous groups, sanitized, and immersed to acaricide diluted according to the manufacturer's statement, on sequence there was incubated. After the incubation was obtained from female reproductive efficiency and effectiveness of the tested acaricides. The association cypermethrin+ chlorpyrifos + citronellal showed satisfactory efficiency (> 95% in all the properties (mean 99.86% in properties, followed by trichlorfon (83.45%, amitraz (72.33%, neem oil (67.23% and cypermethrin (22.97%, which was not effective in any property. It indicates the use of the association cypermethrin +chlorpyrifos+ citronellal on evaluated properties for control of cattle tick effectively.

  14. Characterization of proteinases from the midgut of Rhipicephalus (Boophilus microplus involved in the generation of antimicrobial peptides

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    Craik Charles S

    2010-07-01

    Full Text Available Abstract Background Hemoglobin is a rich source of biologically active peptides, some of which are potent antimicrobials (hemocidins. A few hemocidins have been purified from the midgut contents of ticks. Nonetheless, how antimicrobials are generated in the tick midgut and their role in immunity is still poorly understood. Here we report, for the first time, the contribution of two midgut proteinases to the generation of hemocidins. Results An aspartic proteinase, designated BmAP, was isolated from the midgut of Rhipicephalus (Boophilus microplus using three chromatographic steps. Reverse transcription-quantitative polymerase chain reaction revealed that BmAP is restricted to the midgut. The other enzyme is a previously characterized midgut cathepsin L-like cysteine proteinase designated BmCL1. Substrate specificities of native BmAP and recombinant BmCL1 were mapped using a synthetic combinatorial peptide library and bovine hemoglobin. BmCL1 preferred substrates containing non-polar residues at P2 subsite and polar residues at P1, whereas BmAP hydrolysed substrates containing non-polar amino acids at P1 and P1'. Conclusions BmAP and BmCL1 generate hemocidins from hemoglobin alpha and beta chains in vitro. We postulate that hemocidins may be important for the control of tick pathogens and midgut flora.

  15. Acaricidal activity of leaf extracts of Dalbergia sissoo Roxb. (Fabaceae) against synthetic pyrethroid resistant Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Singh, Nirbhay Kumar; Jyoti; Vemu, Bhaskar; Prerna, Mranalini; Singh, Harkirat; Dumka, V K; Sharma, S K

    2016-06-01

    Resistance status of Rhipicephalus (Boophilus) microplus against synthetic pyrethroids was assessed by larval packet test which revealed level I and II resistance against cypermethrin and deltamethrin, respectively. Adult immersion test was employed to study the acaricidal activity of leaf extracts of Dalbergia sissoo (sheesham) against these ticks. Mortality and fecundity of ticks exposed to sheesham leaf aqueous (SLA) and ethanolic (SLE) extracts were evaluated at concentrations of 0.625, 1.25, 2.5, 5.0 and 10.0% and controls (distilled water and 10% ethanol). Higher acaricidal activity was recorded in SLA with a lower LC50 (95% CL) value of 1.58% (0.92-2.71%) than SLE [5.25% (4.91-5.63%)]. A significant decrease in egg mass weight and reproductive index was recorded in treated ticks along with an increase in percent inhibition of oviposition. A complete inhibition of hatching was recorded in eggs laid by ticks treated with higher concentrations of SLA, whereas, SLE exhibited no effect on hatching percentage. PMID:27234528

  16. Control of Boophilus microplus ticks in cattle calves by immunization with a recombinant Bm86 glucoprotein antigen preparation.

    Science.gov (United States)

    Khalaf-Allah, S S

    1999-06-01

    Forty Egyptian native cattle calves of 4-6 months old randomly allocated into two groups of twenty animals each were used to assess the effect of immunization of animals with a recombinant Bm86 antigen derived from Boophilus microplus ticks on induction of immunity that could protect calves during tick season. The immunization protocol involved two injections administered intramuscularly, the first was applied with complete Freund's adjuvant and the second was given with incomplete Freund's adjuvant two months later. Control calves were given saline plus adjuvant. Immunization reduced the number of adult ticks developing from a subsequent challenge infestation by 78% in immunized calves. Vaccination also, significantly reduced the weight of adult ticks in immunized calves (30.51%). The results of skin delayed hypersensitivity reaction revealed that the diameter of sites injected with the recombinant Bm86 antigen was significantly larger in immunized calves than those in controls. Analysis of the immune response indicated that there was a significant increase in the level of IgG and IgA antibodies in serum of immunized calves and protection from reinfestation was correlated with the levels of circulating antibodies. PMID:10422372

  17. Field studies and cost-effectiveness analysis of vaccination with Gavac against the cattle tick Boophilus microplus.

    Science.gov (United States)

    de la Fuente, J; Rodríguez, M; Redondo, M; Montero, C; García-García, J C; Méndez, L; Serrano, E; Valdés, M; Enriquez, A; Canales, M; Ramos, E; Boué, O; Machado, H; Lleonart, R; de Armas, C A; Rey, S; Rodríguez, J L; Artiles, M; García, L

    1998-02-01

    The control of tick infestations and the transmission of tick-borne diseases remains a challenge for the cattle industry in tropical and subtropical areas of the world. Traditional control methods have been only partially successful and the parasites continue to result in significant losses for the cattle industry. Recently, vaccines containing the recombinant Boophilus microplus gut antigen Bm86 have been developed. These vaccines have been shown to control tick infestations in the field. However, extensive field studies investigating the efficacy and cost-effectiveness of vaccination have not been reported and are needed to appraise the effect of this new approach for tick control. Here is reported the results of the application of Gavac in a field trial including more than 260,000 animals in Cuba. In this study the correlation between the antibody response to vaccination and the effect on ticks fertility is determined. Physiological status of the animals was found to affect the primary response to vaccination but not the antibody titers after revaccination. A cost-effectiveness analysis showed a 60% reduction in the number acaricide treatments, together with the control of tick infestations and transmission of babesiosis, which resulted in savings of $23.4 animal-1 year-1. These results clearly demonstrate the advantage of vaccination and support the application of Gavac for tick control. PMID:9607057

  18. Simulation of control strategies for the cattle tick Boophilus microplus employing vaccination with a recombinant Bm86 antigen preparation.

    Science.gov (United States)

    Labarta, V; Rodríguez, M; Penichet, M; Lleonart, R; Luaces, L L; de la Fuente, J

    1996-05-01

    Current strategies for the control of the cattle tick Boophilus microplus include the use of chemicals as the principal control method. These methods, however, have met with partially successful results. The recent development of immunological methods for the control of the cattle tick has opened new possibilities for the design of control strategies. Employing the results obtained by us in experiments testing the effect of vaccination with the recombinant vaccine, Gavac (Heber Biotec S.A.), on tick populations, we have developed a model to evaluate, through a computer program, the efficacy of the vaccine as a control method. The action of the vaccine on the control of tick populations was simulated and the specific serum antibody titers required to decrease the tick population in the field were calculated. The specific serum antibody titer required to decrease the tick population in the field after the first vaccination scheme was found to be > or = 57,200 and the antibody titer required to maintain this effect when the vaccine is already acting and after successive revaccinations was found to be > or = 27,500. Considerations about revaccination schemes and combination between vaccination and acaricide treatments as possible control strategies are discussed. PMID:8792587

  19. Perceptions about the biology of Rhipicephalus (Boophilus microplus among milk producers in Divinópolis, Minas Gerais Percepção dos produtores de leite de Divinópolis, Minas Gerais, sobre a biologia do Rhipicephalus (Boophilus microplus

    Directory of Open Access Journals (Sweden)

    Christiane Maria Barcellos Magalhães da Rocha

    2011-12-01

    Full Text Available One hundred semi-systematized interviews were applied with the aim of surveying the perceptions of milk producers in the municipality of Divinópolis, Minas Gerais regarding the biology of the tick Rhipicephalus (Boophilus microplus. Content analysis was conducted on each of the variables surveyed and their descriptions, highlighting the higher frequencies in order to construct profiles of perceptions about each of the matters surveyed. In addition, each of the producers was categorized regarding their readiness to proceed with efficient control, from the assessment of their responses. Among the variables surveyed were the tick lifespan, duration of parasitic life, time of greatest incidence, survival in pastures and egg-laying volume. These questions are considered important for defining the knowledge needed for rational combat. It was concluded that the information needed for adopting effective practices to combat ticks was insufficient among the milk farm properties in Divinópolis. Moreover, the producers interviewed had a good perception of what they observed in their daily routine, but did not have complementary information about the tick life cycle.Foram aplicadas 100 entrevistas semissistematizadas com o objetivo de levantar a percepção dos produtores de leite do município de Divinópolis, Minas Gerais, sobre a biologia do carrapato Rhipicephalus (Boophilus microplus. Foi feita "análise de conteúdo" de cada uma das variáveis levantadas e sua descrição com destaque das maiores frequências para a construção de perfis de percepção sobre cada um dos aspectos levantados. Além disso, cada um dos produtores foram categorizados quanto a estar ou não apto a proceder um controle eficiente pela avaliação de suas respostas. Algumas das variáveis levantadas foram tempo de vida do carrapato, tempo de vida parasitária, época de maior incidência, sobrevivência nas pastagens e volume de postura, questões consideradas importantes

  20. Synthetic vaccine (SBm7462) against the cattle tick Rhipicephalus (Boophilus) microplus: preservation of immunogenic determinants in different strains from South America.

    Science.gov (United States)

    Peconick, A P; Sossai, S; Girão, F A; Rodrigues, M Q R B; Souza E Silva, C H; Guzman Q, F; Patarroyo V, A M; Vargas, M I; Patarroyo, J H

    2008-05-01

    The synthetic vaccine SBm7462 is based on three immunogenic epitopes (4822, 4823 and 4824) contained within protein Bm86 derived from the Australian Yeerongpilly strain of the tick Rhipicephalus (Boophilus) microplus. Twenty strains of the tick originating from Brazil, Argentina, Colombia and Uruguay were analysed in order to identify differences compared with sequences present in components of vaccine SBm7462. For each parasite population, three cDNA fragments containing the nucleotides coding for the epitopes 4822, 4824 and 4823 were sequenced, and the amino acid sequences were deduced and compared with those of the homologous bm86 gene. The results indicate that the epitope sequences of vaccine SBm7462 are conserved in the South American populations of the tick. The conservation of such sequences is very important for the immunological response of different populations of R. (B.) microplus. PMID:18226809

  1. Detección inmunoquímica de esterasas en dos cepas de la garrapata boophilus microplus (acarii: ixodidae) resistentes a ixodicidas

    OpenAIRE

    Rodrigo Rosario Cruz; Zeferino García Vázquez; John George Edward

    2000-01-01

    Se encontró una esterasa en Boophilus microplus con actividad incrementada, en dos cepas de garrapatas resistentes a acaricidas de la familia de los piretroides y organofosforados, que fue detectada después de ser separadas electroforéticamente. La proteína fue separada y utilizada en la preparación de un anticuerpo policlonal monoespecífico. La especificidad de este anticuerpo fue probada mediante un ensayo de inmunoelectrotransferencia, en extractos totales de dos cepas de garrapatas resist...

  2. Utilización del Boophilus microplus como remedio isopático en el control del ectoparásito en el Municipio de Aguazul (Casanare)

    OpenAIRE

    Francisco Javier Niño Murcia; Edwin Gustavo Morales Arguello

    2005-01-01

    En este estudio se demostró la efectividad de un remedio isopático vía oral, para el control de la garrapata Boophilus microplus, inocuo para los animales, medio ambiente y el hombre, evitando residuos de plaguicidas en el producto final. La investigación se realizó en una finca ubicada en el municipio de Aguazul (Casanare); localizada a los 05°10’23’’ de latitud norte y 72°33’17’’ de longitud oeste desde Greenwich, altitud: 300 msnm, temperatura media: 27ÚC. Precipitación anual media: 2.441 ...

  3. Persistencia de la eficacia de dos lactonas macrocíclicas contra infestaciones naturales de Rhipicephalus (Boophilus) microplus en bovinos del trópico mexicano

    OpenAIRE

    Ronnie de Jesús Arieta-Román; Roger Iván Rodríguez-Vivas; José Alberto Rosado- Aguilara; Genny Trinidad Ramírez-Cruz; Gertrudis Basto-Estrella

    2010-01-01

    Se evaluó la persistencia de la eficacia de ivermectina-3.15% (IVM-3.15%) y moxidectina-10% (MOX-10%) contra infestaciones naturales de Rhipicephalus (Boophilus) microplus en bovinos del trópico mexicano. Para ello se utilizaron 33 bovinos hembras que fueron distribuidos en tres grupos (n=11) recibiendo los siguientes tratamientos: a) IVM-3.15% (0.63 mg/kg de peso vivo por vía subcutánea; b) MOX-10% (1 mg/kg de peso vivo por vía subcutánea); c) grupo testigo. El número de garrapatas adultas f...

  4. Efficacy of fipronil (1.0 mg/kg) against Rhipicephalus (Boophilus) microplus strains resistant to ivermectin (0.63 mg/kg).

    Science.gov (United States)

    Lopes, Welber Daniel Zanetti; Cruz, Breno Cayeiro; Teixeira, Weslen Fabrício Pires; Felippelli, Gustavo; Maciel, Willian Giquelin; Buzzulini, Carolina; Gomes, Lucas V Costa; Favero, Flávia; Soares, Vando Edésio; Bichuette, Murilo A; de Oliveira, Gilson Pereira; da Costa, Alvimar José

    2014-08-01

    The present study aimed to evaluate the efficacy of fipronil (1 mg/kg) against three strains of ivermectin-resistant Rhipicephalus (Boophilus) microplus (R. (B.) microplus), naturally infesting cattle from different states of Brazil. Three rural properties with a history of macrocyclic lactones ineffectiveness against the cattle tick, and low frequency use of fipronil in the herd, were selected for the study. The animals were randomized according to the mean tick counts, performed on days -3, -2 and -1, into three groups with 10 animals each: T01, control (saline solution); T02, subcutaneous ivermectin (0.63 mg/kg) and T03, topical fipronil (1 mg/kg). Treatment was performed on day 0. Counts of partially engorged female ticks were performed on days 3, 7 and 14 post-treatment (DPT), and then every 7 days until the 49th DPT. In all three experiments, it was possible to diagnose resistance of R. (B.) microplus to ivermectin (0.63 mg/kg). The maximum efficacy (arithmetic mean) obtained for ivermectin was 64% in experiment II. On the other hand, the formulation containing fipronil (1 mg/kg) reached high efficacy values (≥97%) in all three experiments. The results from all experiments in this study demonstrate the high efficacy of 1mg/kg fipronil, administered pour-on in naturally infested cattle, against strains of R. (B.) microplus that are resistant to 630 mcg/kg ivermectin. PMID:24853051

  5. Control of ticks resistant to immunization with Bm86 in cattle vaccinated with the recombinant antigen Bm95 isolated from the cattle tick, Boophilus microplus.

    Science.gov (United States)

    García-García, J C; Montero, C; Redondo, M; Vargas, M; Canales, M; Boue, O; Rodríguez, M; Joglar, M; Machado, H; González, I L; Valdés, M; Méndez, L; de la Fuente, J

    2000-04-28

    The recombinant Bm86-containing vaccine Gavac(TM) against the cattle tick Boophilus microplus has proved its efficacy in a number of experiments, especially when combined with acaricides in an integrated manner. However, tick isolates such as the Argentinean strain A, show low susceptibility to this vaccine. In this paper we report on the isolation of the Bm95 gene from the B. microplus strain A, which was cloned and expressed in the yeast Pichia pastoris producing a glycosylated and particulated recombinant protein. This new antigen was effective against different tick strains in a pen trial, including the B. microplus strain A, resistant to vaccination with Bm86. A Bm95-based vaccine was used to protect cattle against tick infestations under production conditions, lowering the number of ticks on vaccinated animals and, therefore, reducing the frequency of acaricide treatments. The Bm95 antigen from strain A was able to protect against infestations with Bm86-sensitive and Bm86-resistant tick strains, thus suggesting that Bm95 could be a more universal antigen to protect cattle against infestations by B. microplus strains from different geographical areas. PMID:10717348

  6. Evolutionary conserved microRNAs are ubiquitously expressed compared to tick-specific miRNAs in the cattle tick Rhipicephalus (Boophilus microplus

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    Tateno Yoshio

    2011-06-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are small non-coding RNAs that act as regulators of gene expression in eukaryotes modulating a large diversity of biological processes. The discovery of miRNAs has provided new opportunities to understand the biology of a number of species. The cattle tick, Rhipicephalus (Boophilus microplus, causes significant economic losses in cattle production worldwide and this drives us to further understand their biology so that effective control measures can be developed. To be able to provide new insights into the biology of cattle ticks and to expand the repertoire of tick miRNAs we utilized Illumina technology to sequence the small RNA transcriptomes derived from various life stages and selected organs of R. microplus. Results To discover and profile cattle tick miRNAs we employed two complementary approaches, one aiming to find evolutionary conserved miRNAs and another focused on the discovery of novel cattle-tick specific miRNAs. We found 51 evolutionary conserved R. microplus miRNA loci, with 36 of these previously found in the tick Ixodes scapularis. The majority of the R. microplus miRNAs are perfectly conserved throughout evolution with 11, 5 and 15 of these conserved since the Nephrozoan (640 MYA, Protostomian (620MYA and Arthropoda (540 MYA ancestor, respectively. We then employed a de novo computational screening for novel tick miRNAs using the draft genome of I. scapularis and genomic contigs of R. microplus as templates. This identified 36 novel R. microplus miRNA loci of which 12 were conserved in I. scapularis. Overall we found 87 R. microplus miRNA loci, of these 15 showed the expression of both miRNA and miRNA* sequences. R. microplus miRNAs showed a variety of expression profiles, with the evolutionary-conserved miRNAs mainly expressed in all life stages at various levels, while the expression of novel tick-specific miRNAs was mostly limited to particular life stages and/or tick organs. Conclusions

  7. Acaricide resistance of Rhipicephalus (Boophilus microplus in State of Mato Grosso do Sul, Brazil Resistência do Rhipicephalus (Boophilus microplus aos acaricidas no Estado de Mato Grosso do Sul, Brasil

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    Renato Andreotti

    2011-06-01

    Full Text Available This study was conducted to obtain an epidemiological view of acaricide resistance in populations of Rhipicephalus (Boophilus microplus in the State of Mato Grosso do Sul. Twenty-four tick samples were collected from municipalities in the State where farmers had reported concerns about resistance to or failure of tick control. These ticks were subjected to in vitro resistance detection assays using the adult immersion test (AIT. The efficacy of alpha-cypermethrin, cypermethrin and amitraz treatments on samples collected throughout the State was generally poor. AIT showed efficacy > 90% from the use of DDVP + chlorfenvinphos (20 out of 21 municipalities, dichlorvos + cypermethrin (10 out of 16 municipalities and cypermethrin + citronella + chlorpyrifos + piperonyl butoxide (20 out of 21 municipalities. PCR assays were used to detect the presence of pyrethroid resistance-associated sodium channel gene mutation. Larvae from three different populations that had previously been diagnosed as pyrethroid-resistant, through AIT, were evaluated. The PCR assays showed that the pyrethroid resistance-associated gene mutation was absent from these three populations. This study confirms that the emergence of resistance is a constant challenge for the livestock industry, and that development of resistance continues to be a major driver for new antiparasitic drugs to be developed.Este estudo foi realizado com o objetivo de se obter uma visão epidemiológica da resistência aos acaricidas nas populações de Rhipicephalus (Boophilus microplus no Estado de Mato Grosso do Sul. Vinte e quatro amostras de carrapatos foram coletadas em cidades do estado onde os fazendeiros relataram preocupação com resistência ou falha no controle dos carrapatos. Estes carrapatos foram submetidos a testes de detecção de resistência in vitro usando o teste de imersão de adultos (TIA. A eficácia do tratamento com alfa-cipermetrina, cipermetrina e amitraz foi geralmente pobre

  8. Perceptions of milk producers from Divinópolis, Minas Gerais, regarding Rhipicephalus (Boophilus microplus control Percepção dos produtores de leite de Divinópolis, Minas Gerais, sobre o controle de Rhipicephalus (Boophilus microplus

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    Christiane Maria Barcellos Magalhães da Rocha

    2011-12-01

    Full Text Available Semi-systematized interviews were conducted with 100 dairy cattle producers in the municipality of Divinópolis, Minas Gerais, with the aim of ascertaining their perceptions regarding the importance of Rhipicephalus (Boophilus microplus and of combating it. Content analysis was performed and the frequency distribution of each of the variables was used to construct profiles of the producers interviewed. The production losses caused by ticks were perceived incompletely by the producers, who were unaware of the pathogen transmission caused by the parasite and the indirect losses through combating it, such as the cost of acaricide and labor. The combat operations were performed in a traditional manner, with an excessive number of inefficient treatments that aimed to control the level of infestation at that moment. The quality of the acaricide dipping/spraying applied was affected by the quality of the equipment used to apply the products, lack of knowledge of the mode of action of these products, lack of the specific information needed and lack of motivation caused by unawareness of the disadvantages of chemical combat. It was concluded that the lack of knowledge about combat methods and the acceptance of endemicity of the parasitosis were impediments to changing the realities encountered.Entrevistas semissistematizadas foram aplicadas a 100 produtores de bovinos leiteiros do município de Divinópolis, Minas Gerais, com o objetivo de verificar a sua percepção sobre a importância de Rhipicephalus (Boophilus microplus e seu combate. Foi feita "análise de conteúdo" e a distribuição de frequência de cada uma das variáveis para a construção de perfis dos produtores entrevistados. Os prejuízos causados à produção pelo carrapato são percebidos de forma incompleta pelos produtores, que ignoram a transmissão de patógenos pelo parasito e as perdas indiretas pelo combate, como o custo do carrapaticida e da mão de obra. O combate era feito

  9. Rhipicephalus (Boophilus) microplus tick in vitro feeding methods for functional (dsRNA) and vaccine candidate (antibody) screening.

    Science.gov (United States)

    Lew-Tabor, Ala E; Bruyeres, Anthea G; Zhang, Bing; Rodriguez Valle, Manuel

    2014-09-01

    Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) ticks cause economic losses for cattle industries throughout tropical and subtropical regions of the world estimated at $US2.5 billion annually. Lack of access to efficacious long-lasting vaccination regimes and increases in tick acaricide resistance have led to the investigation of targets for the development of novel tick vaccines and treatments. In vitro tick feeding has been used for many tick species to study the effect of new acaricides on the transmission of tick-borne pathogens. Few studies have reported the use of in vitro feeding for functional genomic studies using RNA interference and/or the effect of specific anti-tick antibodies. In particular, in vitro feeding reports for the cattle tick are limited due to its relatively short hypostome. Previously published methods were further modified to broaden optimal tick sizes/weights, feeding sources including bovine and ovine serum, optimisation of commercially available blood anti-coagulant tubes, and IgG concentrations for effective antibody delivery. Ticks are fed overnight and monitored for ∼5-6 weeks to determine egg output and success of larval emergence using a humidified incubator. Lithium-heparin blood tubes provided the most reliable anti-coagulant for bovine blood feeding compared with commercial citrated (CPDA) and EDTA tubes. Although >30mg semi-engorged ticks fed more reliably, ticks as small as 15mg also fed to repletion to lay viable eggs. Ticks which gained less than ∼10mg during in vitro feeding typically did not lay eggs. One mg/ml IgG from Bm86-vaccinated cattle produced a potent anti-tick effect in vitro (83% efficacy) similar to that observed in vivo. Alternatively, feeding of dsRNA targeting Bm86 did not demonstrate anti-tick effects (11% efficacy) compared with the potent effects of ubiquitin dsRNA. This study optimises R. microplus tick in vitro feeding methods which support the development of cattle tick vaccines and

  10. Acaricidal activity of Cymbopogon winterianus, Vitex negundo and Withania somnifera against synthetic pyrethroid resistant Rhipicephalus (Boophilus) microplus.

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    Singh, Nirbhay Kumar; Jyoti; Vemu, Bhaskar; Nandi, Abhijit; Singh, Harkirat; Kumar, Rajender; Dumka, V K

    2014-01-01

    Detection of resistance levels against cypermethrin and deltamethrin, the most commonly used synthetic pyrethroids (SPs) against Rhipicephalus (Boophilus) microplus collected from Moga, Punjab (India) was carried out using larval packet test. Results indicated the presence of resistance of level I and III against cypermethrin (resistance factors (RF) = 4.67) and deltamethrin (RF = 34.2), respectively. Adult immersion test was used to assess the acaricidal activity of aqueous and ethanolic extracts of leaves of Cymbopogon winterianus, Vitex negundo, and Withania somnifera along with roots of V. negundo against the SP resistant engorged females of R. (B.) microplus. The efficacy of various extracts was assessed by estimation of percent adult mortality, reproductive index (RI), percent inhibition of oviposition (%IO), and hatching rate. A concentration dependent increase in tick mortality was recorded which was more marked with various ethanolic extracts, and highest mortality was recorded in ticks treated with ethanolic extract of leaves of C. winterianus. The LC50 values were determined by applying regression equation analysis to the probit transformed data of mortality for various aqueous and ethanolic extracts. Acaricidal property was recorded to be higher in ethanolic extracts, and high activity was found with the ethanolic extract of leaves of C. winterianus with LC50 (95% CL) values of 0.46% (0.35-0.59%), followed by W. somnifera as 5.21% (4.45-6.09%) and V. negundo as 7.02% (4.58-10.74%). The egg mass weight of the live ticks treated with different concentrations of the various extract was significantly (p < 0.01) lower than that of control ticks; consequently, the RI and the %IO value of the treated ticks were reduced. Further, complete inhibition of hatching was recorded in eggs laid by ticks treated with ethanolic extracts of leaves of V. negundo and aqueous extracts of leaves of W. somnifera. The results of the current study indicate that extracts of C

  11. In Vitro Detection of Acaricidal Resistance Status of Rhipicephalus (Boophilus microplus against Commercial Preparation of Deltamethrin, Flumethrin, and Fipronil from North Gujarat, India

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    K. P. Shyma

    2015-01-01

    Full Text Available Rhipicephalus (Boophilus microplus is the most common tick species in India infesting cattle and buffaloes and causing significant economic losses to dairy and leather industries by adversely affecting the milk production and quality of hides. A study to evaluate the acaricide resistance status of Rhipicephalus (Boophilus microplus to deltamethrin, flumethrin, and fipronil was conducted on the samples collected from organized and unorganized farms of North Gujarat state, where treatment failures were reported frequently. Adult Immersion Test (AIT and Larval Packet Test (LPT were conducted using field strain for determination of 50 and 95% lethal concentration of deltamethrin, flumethrin, and fipronil. Results obtained by the Adult Immersion Test showed low grade resistance (level I, RF > 5 has been developed against both deltamethrin and fipronil. However, deltamethrin by performing Larval Packet Test showed moderate grade resistance (level II, RF > 25. Larval packet performed by flumethrin also revealed low grade resistance, level I. The data on field status of acaricide resistance from the area with diversified animal genetic resources will be helpful to adopt suitable strategy to overcome the process of development of resistance in ticks.

  12. In Vitro Detection of Acaricidal Resistance Status of Rhipicephalus (Boophilus) microplus against Commercial Preparation of Deltamethrin, Flumethrin, and Fipronil from North Gujarat, India.

    Science.gov (United States)

    Shyma, K P; Gupta, Jay Prakash; Singh, Veer; Patel, K K

    2015-01-01

    Rhipicephalus (Boophilus) microplus is the most common tick species in India infesting cattle and buffaloes and causing significant economic losses to dairy and leather industries by adversely affecting the milk production and quality of hides. A study to evaluate the acaricide resistance status of Rhipicephalus (Boophilus) microplus to deltamethrin, flumethrin, and fipronil was conducted on the samples collected from organized and unorganized farms of North Gujarat state, where treatment failures were reported frequently. Adult Immersion Test (AIT) and Larval Packet Test (LPT) were conducted using field strain for determination of 50 and 95% lethal concentration of deltamethrin, flumethrin, and fipronil. Results obtained by the Adult Immersion Test showed low grade resistance (level I, RF > 5) has been developed against both deltamethrin and fipronil. However, deltamethrin by performing Larval Packet Test showed moderate grade resistance (level II, RF > 25). Larval packet performed by flumethrin also revealed low grade resistance, level I. The data on field status of acaricide resistance from the area with diversified animal genetic resources will be helpful to adopt suitable strategy to overcome the process of development of resistance in ticks. PMID:26788362

  13. Efecto ixodicida de los extractos etanólicos de algunas plantas sobre garrapatas Rhipicephalus (Boophilus microplus

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    Ángela Rodríguez S.

    2010-12-01

    Full Text Available Objetivo. Evaluar in vitro, el efecto ixodicida del extracto etanólico de cinco plantas; Brugmasia arborea, Sambucus nigra, Nicotiana tabacum, Bidens pilosa y Ambrosia cumanenses sobre garrapatas adultas de la especie Rhipicephalus (Boophilus microplus. Materiales y métodos. El extracto de cada planta fue obtenido mediante la técnica de lixiviación. Para las pruebas, se utilizaron garrapatas adultas de dos tamaños (pequeñas y medianas, que fueron expuestas a los extractos de cada planta, utilizando la técnica de inmersión de garrapatas adultas. A las 24 h de exposición, se realizó la lectura de mortalidad, donde se tomó como mínimo eficaz una mortalidad del 60%. Las pruebas iniciales se realizaron con extractos puros y cuando éstos mostraban eficacia se procedía a realizar diluciones crecientes, hasta encontrar la concentración mínima eficaz. Estas pruebas fueron realizadas en clima frio y cálido. Resultados. El extracto de N. tabacum, mostró efectividad en garrapata pequeña, hasta las diluciones 0.5:10 y 1:10 en clima frio y cálido, respectivamente y con 2.5:10 y 5:10 sobre garrapata mediana en clima frio y cálido, respectivamente; B. arbórea, mostró eficacia sobre garrapata pequeña hasta la dilución 7.5:10 en ambos climas; S. nigra y B. pilosa solo fueron eficaces en clima cálido sobre garrapatas pequeñas empleando extracto puro. A. cumanenses no fue eficaz en ninguna de las pruebas. Conclusiones. N. tabacum, mostró mayor eficacia y se observó que los mejores resultados se obtuvieron con las mayores concentraciones.

  14. In vitro assessment of the acaricidal activity of computer-selected analogues of carvacrol and salicylic acid on Rhipicephalus (Boophilus) microplus.

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    Concepción, Ramírez L; Froylán, Ibarra V; Herminia I, Pérez M; Norberto, Manjarrez A; Héctor J, Salgado Z; Yeniel, González C

    2013-10-01

    Rhipicephalus (Boophilus) microplus is a tick that causes huge economic losses in cattle. The indiscriminate use of acaricides has generated resistance to most compounds present on the market. This makes further investigation on other potential acaricides necessary, the in silico assay being an alternative to the design of new compounds. In the present study a biosilico assay was performed using TOMOCOMD-CARDD (TOpological MOlecular COMputer Design-Computer-Aided Rational Drug Design) and WEKA (Waikato Environment for Knowledge Analysis) software. Two carvacrol and four salicylic acid derivatives, synthesized by conventional methods and evaluated with the larval packet test on larvae of R. (B.) microplus were selected. All evaluated compounds presented acaricidal activity; however, ethyl 2-methoxybenzoate (91.8 ± 1.7 % mortality) and ethyl 2,5-dihydroxybenzoate (89.1 ± 1.6 % mortality) showed greater activity than salicylic acid. With regard to the carvacrol analogues, carvacrol acetate (67.8 ± 2.1 % mortality) and carvacrol methyl ether (71.7 ± 1.6 % mortality) also showed greater activity than carvacrol (35.9 ± 3.2 % mortality). TOMOCOMD-CARDD and WEKA software were helpful tools in the search for alternative structures with potential acaricidal activity on R. (B.) microplus. PMID:23543288

  15. Chemo-profiling and bioassay of phytoextracts from Ageratum conyzoides for acaricidal properties against Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) infesting cattle and buffaloes in India.

    Science.gov (United States)

    Kumar, K G Ajith; Tayade, Amol B; Kumar, Rajesh; Gupta, Suman; Sharma, Anil Kumar; Nagar, Gaurav; Tewari, Shashi Shankar; Kumar, Bhanu; Rawat, A K S; Srivastava, Sharad; Kumar, Sachin; Ghosh, Srikant

    2016-03-01

    In India, Rhipicephalus (Boophilus) microplus populations have developed a certain level of resistance to most of the acaricides marketed against tick species. To manage the problem, the present study was undertaken to evaluate the acaricidal potential of Ageratum conyzoides plants against acaricides-resistant ticks infesting cattle and buffaloes. The regression analysis of dose-response data of ethanolic extract of A. conyzoides revealed LC90 value of 8.91% against reference susceptible IVRI-1 line of R.(B.) microplus. The ethanolic extract was found efficacious against 76.7-90% acaricides-resistant field ticks and adversely affected oviposition showing 7.04-31.3% reduction in egg laying capacity. The extract was also showed an in vitro efficacy of 52.5 and 76.7% against reference resistant IVRI-4 and 5 lines. The GC/MS/MS profiling of hexane extract, two bioactive sub-fractions and essential oils revealed the presence of 6,7-dimethoxy-2,2-dimethyl-2H-1-benzopyran (precocene II) as a major phyto-compound. The bioactive sub-fractions showed 96.2-97.5% efficacy against larvae of IVRI-1 and 77.1-94.9% against multi-acaricide resistant larvae of IVRI-5 line of R.(B.) microplus. The results of this study provided significant support for the development of a phyto-formulation based on A. conyzoides species. PMID:26723275

  16. Selection of reference genes for quantitative RT-PCR studies in Rhipicephalus (Boophilus microplus and Rhipicephalus appendiculatus ticks and determination of the expression profile of Bm86

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    Jongejan Frans

    2009-12-01

    Full Text Available Abstract Background For accurate and reliable gene expression analysis, normalization of gene expression data against reference genes is essential. In most studies on ticks where (semi-quantitative RT-PCR is employed, normalization occurs with a single reference gene, usually β-actin, without validation of its presumed expression stability. The first goal of this study was to evaluate the expression stability of commonly used reference genes in Rhipicephalus appendiculatus and Rhipicephalus (Boophilus microplus ticks. To demonstrate the usefulness of these results, an unresolved issue in tick vaccine development was examined. Commercial vaccines against R. microplus were developed based on the recombinant antigen Bm86, but despite a high degree of sequence homology, these vaccines are not effective against R. appendiculatus. In fact, Bm86-based vaccines give better protection against some tick species with lower Bm86 sequence homology. One possible explanation is the variation in Bm86 expression levels between R. microplus and R. appendiculatus. The most stable reference genes were therefore used for normalization of the Bm86 expression profile in all life stages of both species to examine whether antigen abundance plays a role in Bm86 vaccine susceptibility. Results The transcription levels of nine potential reference genes: β-actin (ACTB, β-tubulin (BTUB, elongation factor 1α (ELF1A, glyceraldehyde 3-phosphate dehydrogenase (GAPDH, glutathione S-transferase (GST, H3 histone family 3A (H3F3A, cyclophilin (PPIA, ribosomal protein L4 (RPL4 and TATA box binding protein (TBP were measured in all life stages of R. microplus and R. appendiculatus. ELF1A was found to be the most stable expressed gene in both species following analysis by both geNorm and Normfinder software applications, GST showed the least stability. The expression profile of Bm86 in R. appendiculatus and R. microplus revealed a more continuous Bm86 antigen abundance in R

  17. PI3K/PKB signaling in Rhipicephalus (Boophilus) microplus tick embryo cell line BME26

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, L.; Fabres, A.; Logullo, C. [Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, RJ (Brazil). Centro de Biociencias e Biotecnologia. Lab. de Quimica e Funcao de Proteinas e Peptideos (LQFPP)]. E-mail: leoabreu@uenf.br; Esteves, E.; Daffre, S. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Quimica. Dept. de Bioquimica

    2008-07-01

    Full text: Ticks are obligatory blood-sucking arthropods and important vectors of both human and animal diseases. In order to study the insulin triggered pathway and its possible roles during embryogenesis we are using a culture of embryonic Rhipicephalus (Boophilus) micro plus cells (BME26). Besides its metabolic role, insulin signaling pathway (ISP) is widely described as crucial for vertebrate and invertebrate embryogenesis and development. In such cascade Phosphatidylinositol 3-OH Kinase (PI3K) is hierarchically located upstream Protein Kinase B (PKB). Exogenous insulin is able to increase the expression level of PI3K's regulatory sub unity (p85), as determined by Real Time RT-PCR. In the presence of PI3K inhibitors (Wortmannin or LY294002) these effects were reversed. This correlates well with the activation of PKB by phosphorylation, as it appears to be PI3K-dependent. Additionally, PI3K inhibition increased the expression level of two insulin-regulated downstream targets from glycogen metabolism (GSK3b) and gluneogenesis (PEPCK) pathways. GSK3b inhibition by phosphorylation diminished in cells treated with PI3K inhibitors. These results strongly suggest the presence of an insulin sensitive PI3K-PKB axis in BME26 cells. The further study of PI3K and PKB activity in egg homogenates during embryogenesis may help us to understand the role of ISP for R. micro plus development.

  18. Acaricides efficiency on Rhipicephalus (Boophilus microplus from Bahia state North-Central region Eficiência de acaricidas sobreRhipicephalus (Boophilus microplusna região Centro-Norte, Bahia

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    José Tadeu Raynal

    Full Text Available The cattle tick Rhipicephalus (Boophilus microplus is responsible for major losses in the Brazilian livestock, mainly due to reduction in cattle productive performance. Resistance development to major classes of acaricide widely used nowadays has been extensively reported, as well as the occurrence of residues from these compounds in animal products and the environment. This study aimed to evaluate the efficiency of acaricides on R. (B. microplus collected from rural properties in the North-Central region of Bahia State. Ticks were collected in several cattle farms in the cited region, and an in vitro acaricide efficiency assay was performed based on the immersion of ticks in acaricide solutions made according to manufacturers' recommendations. The results obtained in the experiments indicated varying degrees of efficiency of the several bases studied, with the products benzofenilurea, macrocyclic lactone and fipronil showing the highest levels of efficiency, 100%, 100% and 97.34%, respectively. It was possible to conclude that, for the region studied, there are different degrees of commercial acaricides efficiency, and many present less than 95% effectiveness, value determined as acceptable by the Brazilian legislation.O carrapato Rhipicephalus (Boophilus microplus é responsável por grandes perdas na pecuária brasileira, principalmente devido à redução no desempenho produtivo dos animais. A resistência do parasita a diferentes classes de acaricidas tem sido amplamente relatada, bem como os problemas de ocorrência de resíduos desses compostos em produtos de origem animal e no ambiente. Esse estudo teve como objetivo avaliar a eficiência de diversos acaricidas sobre populações de R. (B. microplus provenientes de propriedades rurais da Região Centro-Norte do Estado da Bahia, Brasil. Teleóginas ingurgitadas foram colhidas em diferentes propriedades da região e submetidas a ensaio in vitro de eficiência de acaricidas, baseado na

  19. Conditions for stable parapatric coexistence between Boophilus decoloratus and B. microplus ticks: a simulation study using the competitive Lotka-Volterra model.

    Science.gov (United States)

    Zeman, Petr; Lynen, Godelieve

    2010-12-01

    The autochthonous tick Boophilus decoloratus, and the invasive species Bo. microplus, the tick most threatening the livestock industry in Africa, show complex interactions in their interspecific rivalry. This study was conducted to specify the conditions under which the two competitors can co-exist in equilibrium, and to provide insight into their climate-dependant parapatric distribution in Tanzania. A model of the Lotka-Volterra type was used, taking into account population dispersal and interactions of various kinds. If the model allowed for immunity-mediated competition on cattle, reproductive interference, and an external mortality factor, it explained fairly well the field observation that the borderline between these ticks loosely follows the 22-23°C isotherm and the 58 mm isohyet (i.e. ~700 mm of annual rainfall total). Simulations fully compatible with the pattern of real co-existing populations of Bo. decoloratus and Bo. microplus, characterized by a pronounced population density trough and mutual exclusion of the two ticks on cattle in an intermediary zone between their distributional ranges, were, however, achieved only if the model also implemented a hypothetical factor responsible for some mortality upon encounter of one tick with the other, interpretable as an interaction through a shared pathogen(s). This study also demonstrated the importance of non-cattle hosts, enabling the autochthon to avoid competition with Bo. microplus, for the behaviour of the modelled system. The simulations indicate that a substantial reduction of wildlife habitats and consequently of Bo. decoloratus refugia, may accelerate the replacement of Bo. decoloratus with Bo. microplus much faster than climatic changes might do.

  20. Survey of acaricides resistance status of Rhipiciphalus (Boophilus) microplus collected from selected places of Bihar, an eastern state of India.

    Science.gov (United States)

    Ghosh, Srikant; Kumar, Rinesh; Nagar, Gaurav; Kumar, Sachin; Sharma, Anil Kumar; Srivastava, Aman; Kumar, Suman; Ajith Kumar, K G; Saravanan, B C

    2015-07-01

    Monitoring acaricide resistance in field ticks and use of suitable managemental practices are essential for controlling tick populations infesting animals. In the present study, the acaricide resistance status in Rhipicephalus (Boophilus) microplus ticks infesting cattle and buffaloes of five districts located in the eastern Indian state, Bihar were characterized using three data sets (AIT, Biochemical assays and gene sequences). Adult immersion test (AIT) was adopted using seven field isolates and their resistance factor (RF) was determined. Six isolates (DNP, MUZ, BEG, VSH, DRB and SUL) were found resistant to both deltamethrin and diazinon and except VSH all were resistant to cypermethrin. One isolate (PTN) was susceptible with a RF below 1.5. To understand the possible mode of resistance development, targeted enzymes and gene sequences of the para sodium channel and achetylcholinesterase 2 (AChE2) were analyzed. The esterase, monooxygenase and glutathione-S-transferase (GST) activity of reference susceptible IVRI-I line was determined as 2.47 ± 0.007 nmol/min/mg protein, 0.089 ± 0.0016 nmol/mg of protein and 0.0439 ± 0.0003 nmol/mg/min respectively, which increased significantly in the resistant field isolates. However, except esterases, the fold increase of monooxygenase (1.14-2.27 times) and GST (0.82-1.53 times) activities were not very high. A cytosine (C) to adenine (A) nucleotide substitution (CTC to ATC) at position 190 in domain II S4-5 linker region was detected only in one isolate (SUL) having RF of 34.9 and in the reference deltamethrin resistant line (IVRI-IV). However, the T2134A mutation was not detected in domain IIIS6 transmembrane segment of resistant isolates and also in reference IVRI-IV line despite of varying degree of resistance. The flumethrin specific G215T and the recently identified T170C mutations were also absent in domain II sequences under study. Four novel amino acid substitutions in AChE2 gene of field isolates and in

  1. Infestación natural de hembras de Boophilus microplus Canestrini, 1887 (Acari: Ixodidae) en dos genotipos de bovinos en el trópico húmedo de Veracruz, México

    OpenAIRE

    Miguel Ángel Alonso Díaz; Barud Josué López Silva; Ana Carolina Leme de Magalhães Labarthe; Roger Iván Rodríguez Vivas

    2007-01-01

    El objetivo del presente estudio fue determinar la dinámica poblacional anual de Boophilus microplus en dos genotipos de ganado bovino. El estudio se realizó en Martínez de la Torre, Veracruz, México (región trópico húmeda). Se utilizaron 20 toretes de diez meses de edad y 185 kg de peso, infestados naturalmente con garrapatas B. microplus. Se formaron dos grupos de diez animales cada uno, según el genotipo (¾ Bos taurus [½ Holstein, ¼ Simmental, ¼ Cebú] y ½ Bos taurus [½ Holstein, ½ Cebú]). ...

  2. INCIDENCE OF Boophilus microplus AND BLOOD PARAMETERS IN CROSSBRED STEERS FED OF SUNFLOWER INCIDÊNCIA DE Boophilus microplus E AVALIAÇÃO DOS PARÂMETROS SANGÜÍNEOS EM BOVINOS MESTIÇOS (HOLANDÊS x ZEBU ALIMENTADOS COM GIRASSOL

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    Sérgio Luíz S. Rezende

    2007-07-01

    Full Text Available This experiment aimed to evaluate the efficacy of sunflower meal and sunflower seeds to control Boophilus microplus in naturally infested steers. The experiment was developed in the Dairy Cattle Facilities of the Veterinary College - UFG. Two herds of steers (Holstein x zebu were allotted in a randomized block design in 2x10 factorial arrangement with six repetitions on Brachiaria decumbens pastures. After 14 days, weekly for two months, B. microplus females > 4 mm were counted, blood samples were collected and the animals were weighed. The B. microplus engorged females were collected to evaluate reproductive parameters. Blood samples were processed to determine: hematocrit, total protein, fibrinogen and leukocytes. The results had been submitted to the analysis of variance and the averages compared for the Scott-Knott test (5%. Tick counts, index (%, larval eclosion, hematocrit, total protein, fibrinogen and leukocytes were similar between treatments. The results do not corroborate the empirical reports concerning the effectiveness of the sunflower to control B. microplus in crossbred steers. KEY-WORDS: Blood values, oily seeds, parasites, tick count. Objetivou-se avaliar a ação do farelo ou das sementes de girassol no controle de Boophilus microplus em novilhos mestiços (holandês x zebu infestados naturalmente. O experimento foi desenvolvido no Setor de Bovinocultura do Departamento de Produção Animal da Escola de Veterinária (EV da UFG. Foram utilizados dois lotes de animais, distribuídos inteiramente ao acaso num fatorial 2 x 10 com seis repetições, em piquetes de Brachiaria decumbens, onde foram suplementados. Após quatorze dias de experimento e a cada sete dias, durante dois meses, num curral de manejo, efetuaram-se a contagem das fêmeas de B. microplus > 4 mm, as coletas de sangue e as pesagens dos bovinos. Colheram-se fêmeas ingurgitadas de B. microplus para avaliação de parâmetros reprodutivos. Amostras de sangue

  3. Strategic applications of long-acting acaricides against Rhipicephalus (Boophilus) microplus in northwestern Argentina, with an analysis of tick distribution among cattle.

    Science.gov (United States)

    Nava, Santiago; Mangold, Atilio J; Canevari, José T; Guglielmone, Alberto A

    2015-03-15

    Strategic applications of long-acting acaricides for the control of Rhipicephalus (Boophilus) microplus in northwestern Argentina were evaluated for one year. In addition, tick distribution among cattle was analyzed to evaluate if partial selective treatment or culling the small proportion of most heavily infested animals were feasible options to control R. (B.) microplus. Two different treatments schemes based on two applications of fluazuron and one application of 3.15% ivermectin were performed. Treatments were made in late winter and spring so as to act on the small 1st spring generation of R. (B.) microplus, in order to preclude the rise of the larger autumn generation. The overall treatment effect was positively significant in both schemes. The number of ticks observed in the control group was significantly higher than in the treated groups on all post-treatment counts. Group 2 exhibited more than 80% of efficacy almost throughout the study period, whereas Group 1 exhibited an efficacy percentage higher than 80% in September, October, December, February, April and May, but not in November (73.4%), January (58.3%), March (45.2%) or June (53.4%). Absolute control was observed in Group 2 in the counts of September and October, and in Group 1 in the count of February. The control strategies evaluated in this work provide an acceptable control level with only three applications of acaricides; at the same time, they prevent the occurrence of the autumn peak of tick burdens, which is characteristic of R. (B.) microplus in northwestern Argentina. Tick distribution was markedly aggregated in all counts. Although ticks were not distributed evenly among calves, the individual composition of the most heavily infested group was not consistent throughout the study period. In addition, the level of aggregation varied with tick abundance. These results suggest that applying acaricides to a portion of the herd or culling the most infested individuals at a given moment of the

  4. Two initial vaccinations with the Bm86-based Gavacplus vaccine against Rhipicephalus (Boophilus microplus induce similar reproductive suppression to three initial vaccinations under production conditions

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    Fernández Erlinda

    2010-09-01

    Full Text Available Abstract Background The cattle tick, Rhipicephalus (Boophilus microplus, affects livestock production in many regions of the world. Up to now, the widespread use of chemical acaricides has led to the selection of acaricide-resistant ticks and to environmental contamination. Gavacplus is a subunit vaccine based on the recombinant Bm86 tick antigen expressed in yeast, capable to control infestations of R. microplus under controlled and production conditions. The vaccine constitutes the core element of broad control programs against this ectoparasite, in which acquired immunity in cattle to Bm86 is combined with a rational use of acaricides. At present, the conventional vaccine scheme consists of three doses that should be administered at weeks 0, 4 and 7, followed by a booster every six months. Results In this study we assayed a reduction in the number of the initial doses of Gavacplus, evaluated the time course and the level of bovine anti-Bm86 antibodies elicited, and analyzed the vaccine effect on ticks engorging on immunized cattle under production conditions. Following three different immunization schemes, the bovines developed a strong and specific immune response characterized by elevated anti-Bm86 IgG titers. A reduction in the weight of engorging female ticks, in the weight of the eggs laid and also in R. microplus viable eggs percentage was obtained by using only two doses of Gavacplus administered at weeks 0 and 4, followed by a booster six months later. This reduction did not differ from the results obtained on ticks engorging on cattle immunized at weeks 0, 4 and 7. It was also demonstrated that anti-Bm86 antibody titers over 1:640, measured in bovines immunized at weeks 0 and 4, were sufficient to affect weight and reproductive potential of female ticks as compared with ticks engorging on unvaccinated animals. In addition, no statistically significant differences were detected in the average weight of eggs laid by ticks engorged on

  5. In vitro and in vivo evaluation of cypermethrin, amitraz, and piperonyl butoxide mixtures for the control of resistant Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) in the Mexican tropics.

    Science.gov (United States)

    Rodriguez-Vivas, R I; Li, A Y; Ojeda-Chi, M M; Trinidad-Martinez, I; Rosado-Aguilar, J A; Miller, R J; Pérez de León, A A

    2013-10-18

    A study was conducted to evaluate the efficacy of cypermethrin, amitraz, and piperonyl butoxide (PBO) mixtures, through in vitro laboratory bioassays and in vivo on-animal efficacy trials, for the control of resistant Rhipicephalus (Boophilus) microplus on cattle in the Mexican tropics. Also, to examine mechanisms of resistance to cypermethrin in this tick population, the frequency of a mutated sodium channel gene (F1550I) was determined using a PCR assay. Results of laboratory bioassays using modified larval packet tests revealed that cypermethrin toxicity was synergized by PBO (from 46.6-57.0% to 83.7-85.0% larval mortality; Presistant tick larvae in vitro (96.7-100% of larval mortality). Tick larvae surviving exposure to cypermethrin or mixtures either with amitraz and PBO in vitro showed 2.9-49.6 higher probability to present the mutated allele than those killed by acaricide treatment (P95% control that persisted for 28 days post-treatment against R. microplus infesting cattle when tested under field conditions in the Mexican tropics. Although this mixture is a potentially useful tool to combat pyrethroid resistance, a product based on an acaricide mixture like the one tested in this study has to be used rationally. PMID:23948559

  6. Determination of acaricide resistance in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) field populations of Argentina, South Africa, and Australia with the Larval Tarsal Test.

    Science.gov (United States)

    Lovis, L; Reggi, J; Berggoetz, M; Betschart, B; Sager, H

    2013-03-01

    Infestations with ticks have an important economic impact on the cattle industry worldwide and resistance to acaricides has become a widespread phenomenon. To optimize their treatment strategy, farmers need to know if and against which classes potential acaricide-resistance does occur. Bioassays are used to assess the resistance level and pattern of Rhipicephalus (Boophilus) microplus populations. The objective of the current study was to assess the susceptibility of field populations originating from Argentina (8), South Africa (3), and Australia (2) using the Larval Tarsal Test. Nine acaricidal compounds from five major classes were tested: organosphosphates, synthetic pyrethroids (SP), macrocyclic lactones, phenylpyrazols, and amidines. The resistance ratios at concentrations inducing 50 and 90% mortality were used to detect established and emerging resistance. This study confirmed the newly reported presence of amitraz resistance in populations from Argentina In addition, resistance to SP appeared to be widespread (88%) in the Argentinean farms, which had been selected based on the observation of lack of treatment efficacy by farmers. In South Africa one of the three populations was found to be resistant to SP and to a phenylpyrazol compound (pyriprol). Furthermore, resistance to organosphosphates and SP was observed in Australia. Finally, the Larval Tarsal Test proved to be a suitable test to evaluate the susceptibility of R. microplus field populations to the most relevant acaricidal classes. PMID:23540121

  7. Tick-susceptible Bos taurus cattle display an increased cellular response at the site of larval Rhipicephalus (Boophilus) microplus attachment, compared with tick-resistant Bos indicus cattle.

    Science.gov (United States)

    Piper, Emily K; Jackson, Louise A; Bielefeldt-Ohmann, Helle; Gondro, Cedric; Lew-Tabor, Ala E; Jonsson, Nicholas N

    2010-03-15

    Cattle demonstrate divergent and heritable phenotypes of resistance and susceptibility to infestation with the cattle tick Rhipicephalus (Boophilus) microplus. Bos indicus cattle are generally more resistant to tick infestation than Bos taurus breeds although large variations in resistance can occur within subspecies and within breed. Increased tick resistance has been previously associated with an intense hypersensitivity response in B. taurus breeds; however, the mechanism by which highly resistant B. indicus cattle acquire and sustain high levels of tick resistance remains to be elucidated. Using the commercially available Affymetrix microarray gene expression platform, together with histological examination of the larval attachment site, this study aimed to describe those processes responsible for high levels of tick resistance in Brahman (B. indicus) cattle that differ from those in low-resistance Holstein-Friesian (B. taurus) cattle. We found that genes involved in inflammatory processes and immune responsiveness to infestation by ticks, although up-regulated in tick-infested Holstein-Friesian cattle, were not up-regulated in Brahman cattle. In contrast, genes encoding constituents of the extracellular matrix were up-regulated in Brahmans. Furthermore, the susceptible Holstein-Friesian animals displayed a much greater cellular inflammatory response at the site of larval R. microplus attachment compared with the tick-resistant Brahman cattle. PMID:19852965

  8. Gene silencing of the tick protective antigens, Bm86, Bm91 and subolesin, in the one-host tick Boophilus microplus by RNA interference.

    Science.gov (United States)

    Nijhof, Ard M; Taoufik, Amar; de la Fuente, José; Kocan, Katherine M; de Vries, Erik; Jongejan, Frans

    2007-05-01

    The use of RNA interference (RNAi) to assess gene function has been demonstrated in several three-host tick species but adaptation of RNAi to the one-host tick, Boophilus microplus, has not been reported. We evaluated the application of RNAi in B. microplus and the effect of gene silencing on three tick-protective antigens: Bm86, Bm91 and subolesin. Gene-specific double-stranded (dsRNA) was injected into two tick stages, freshly molted unfed and engorged females, and specific gene silencing was confirmed by real time PCR. Gene silencing occurred in injected unfed females after they were allowed to feed. Injection of dsRNA into engorged females caused gene silencing in the subsequently oviposited eggs and larvae that hatched from these eggs, but not in adults that developed from these larvae. dsRNA injected into engorged females could be detected by quantitative real-time RT-PCR in eggs 14 days from the beginning of oviposition, demonstrating that unprocessed dsRNA was incorporated in the eggs. Eggs produced by engorged females injected with subolesin dsRNA were abnormal, suggesting that subolesin may play a role in embryonic development. The injection of dsRNA into engorged females to obtain gene-specific silencing in eggs and larvae is a novel method which can be used to study gene function in tick embryogenesis. PMID:17196597

  9. Efficiency of sulphur in garlic extract and non-sulphur homeopathy in the control of the cattle tick Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Costa, L M; Furlong, J

    2011-03-01

    The objective of the present work was to evaluate the efficacy of a non-sulphur-based homeopathic preparation and a sulphur-containing natural product derived from Allium sativum (Linnaeus) against infestation by the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae). A total of 24 crossbred calves (7 : 8 Holstein : Zebu), aged 6-8 months and maintained in individual stables under tick-free conditions, were divided into three groups. Group 1 (control group) received no treatment; Group 2 was treated with 0.01 g/day of the homeopathic preparation Fator C&MC(®), and Group 3 was treated with 20 g/day of Enxofre-Allium sativum(®). After adaptation to the diet for 1 month, each calf was subjected to artificial infestation with 8000 R. (B.) microplus larvae (aged 7-14 days) twice per week over a 5-month period. Numbers of engorged females were recorded every 14 days and samples of freely released engorged females were collected at 14-day intervals commencing 3 months after the start of the experiment. The engorged females were weighed, incubated for 15 days under biochemical oxygen demand conditions at 27 ± 1 °C and relative humidity >85%, and the weights of the egg masses produced were recorded. Other biological parameters, including reproduction estimate, reduction in oviposition and efficiency of treatment, were determined. A significant reduction in the number of engorged females was detected on animals treated with Enxofre-Allium sativum(®) (Group 3) in comparison with the other two groups. The overall efficiency of the treatment with the sulphur-containing product was 64%, whereas that of the homeopathic preparation was 26%. Under the experimental conditions established, Enxofre-Allium sativum(®) can reduce the intensity of the R. (B.) microplus infestation.

  10. Efficacy of amitraz (Taktic 12.5% EC) as a dip for the control of Boophilus microplus (Canestrini) (Acari: Ixodidae) on cattle.

    Science.gov (United States)

    George, J E; Davey, R B; Ahrens, E H; Pound, J M; Drummond, R O

    1998-12-01

    Four groups of cattle infested with Boophilus microplus (Canestrini) were each dipped in a different concentration of amitraz diluted from a 12.5% EC formulation to determine the efficacy and performance of the product in an 11,400 l dipping vat. Except for the period when heifers were dipped, animals were restrained in stanchions placed individually inside 3.3 x 3.3 m2 stalls within an open-sided barn. The amitraz in the vat was stabilized with hydrated lime to maintain a pH of ca. 12. Analyses of vat samples showed that concentrations of amitraz in the vat were 7.6 to 13% lower than the targeted concentrations of 0.010, 0.015, 0.020, and 0.025% active ingredient (AI) for dilutions prepared according to instructions on the manufacturer's label. The large quantity of hydrated lime added to the vat (10 kg/1000 l) interfered with the HPLC analysis of vat samples. Therapeutic efficacy of each of the four observed concentrations (0.0088, 0.0131, 0.0174, and 0.0231% AI) of amitraz was excellent (> 99% control). However, the rapid detachment of all ticks from an animal within a few hours after treatment with amitraz, that has been frequently observed, was not pronounced in the present study. Only 47% of the B. microplus detached in the first 4 h post-treatment, and 84% detached within the first 24 h. All of the treatments, except the lowest concentration, provided protection of cattle against re-infestation by B. microplus larvae for 14 days post-treatment. Possibly as a result of the formation of a compact layer of lime and amitraz on the bottom after the vat was undisturbed for six weeks, intense agitation was required to re-suspend the active ingredient. PMID:9879580

  11. Evaluation in vitro of the infection times of engorged females of Rhipicephalus (Boophilus microplus by the entomopathogenic nematode Steinernema glaseri CCA strain Avaliação in vitro dos tempos de infecção de fêmeas ingurgitadas de Rhipicephalus (Boophilus microplus pelo nematoide entomopatogênico Steinernema glaseri estirpe CCA

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    Leandro Barbiéri de Carvalho

    2010-04-01

    Full Text Available Studies have shown that ticks are susceptible to infection by entomopathogenic nematodes. These studies indicate different susceptibilities of ticks to infection by these fungi, depending on the tick species, development phase, entomopathogenic nematodes species and strains and the time the ticks are exposed to them. Usually this period ranges from 24 to 72 hours. The aim of this study was to evaluate the infection times in vitro of engorged Rhipicephalus (Boophilus microplus females by the entomopathogenic nematodes Steinernema glaseri CCA strain, by analysis of the ticks' biological parameters. The results show that a 2-hour exposure time was sufficient for the engorged R. microplus females to be infected by S. glaseri CCA, but that a minimum exposure time of 24 hours was necessary to generate treatment efficacy above 90%.Os carrapatos são susceptíveis à infecção por nematoides entomopatogênicos. Essa susceptibilidade diverge quanto às espécies de carrapato estudadas, à fase evolutiva, às espécies e estirpes dos nematoides e ao tempo ao qual os carrapatos ficam expostos a estes. O presente trabalho teve como objetivo avaliar os tempos de infecção in vitro de fêmeas ingurgitadas de Rhipicephalus (Boophilus microplus pelo nematoide entomopatogênico Steinernema glaseri estirpe CCA, pela análise dos parâmetros biológicos do carrapato. Os resultados obtidos demonstraram que um período de duas horas de exposição foi suficiente para que fêmeas ingurgitadas de R. microplus fossem infectadas por S. glaseri CCA e que um período de exposição mínimo de 24h foi necessário para que houvesse infecção de fêmeas ingurgitadas de R. microplus por S. glaseri estirpe CCA, capaz de gerar, in vitro, eficácia no tratamento superior a 90%.

  12. Transmisión de cepas atenuadas de babesia bigemina y babesia bovis por garrapatas rhipicephalus (Boophilus) microplus

    OpenAIRE

    Edmundo E. Rojas Ramírez; Juan J. Mosqueda Gualito; Jesús A. Álvarez Martínez; Rubén Hernández Ortíz; Juan A. Ramos Aragón; Carmen Rojas Martínez; Germinal J. Cantó Alarcón; Carlos A. Vega y Murguía; Julio V. Figueroa Millán

    2011-01-01

    Para evaluar la transmisión por garrapatas Rhipicephalus microplus (R. microplus) de una clona atenuada de Babesia bovis (BOR) y una cepa atenuada de Babesia bigemina (BIS), doce bovinos se dividieron en cuatro grupos e infestados de forma escalonada con larvas de R. microplus libres de Babesia spp. Un becerro de cada grupo se inoculó con 1x108 eritrocitos infectados (EI) con BIS, BOR, y cepas virulentas de B. bigemina y B. bovis, respectivamente. Se realizaron dos inoculaciones seriadas adic...

  13. Principal component analysis on the perceptions of milk producers about Rhipicephalus (Boophilus microplus control in Minas Gerais Análise de componente Principal da percepção dos produtores de leite sobre o controle do Rhipicephalus (Boophilus microplus em Minas Gerais

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    Christiane Maria Barcellos Magalhães da Rocha

    2012-09-01

    Full Text Available Milk producers in Lavras, Passos and Divinópolis, Minas Gerais, were interviewed with the aim of evaluating their perceptions and attitudes regarding control over Rhipicephalus (Boophilus microplus. Multivariate correlation between the variables was done by means of principal component analysis. The producers' perceptions and attitudes regarding R. (B. microplus were similar: most of them did not have any basic knowledge of tick biology or control, and they applied acaricide products through backpack spraying, without any defined technical criteria. Some of the results obtained were: I. a negative correlation between schooling level and the frequency of spraying cattle with acaricides; II. a positive correlation between milk production, quality of equipment for acaricide application and technological level of the farm; III. farm properties with greater production and technification tended to keep the intervals between acaricide applications constant over the course of the year. After applying principal component analysis, a positive correlation was observed between schooling level, technological level of the farm and perceptions regarding R. (B. microplus, but without any correlation with attitudes towards controlling this tick. It was concluded that higher technological level and schooling level improved the producers' perceptions relating to the biology of the tick R. (B. microplus, but did not achieve effectiveness with regard to using controls more rationally.Produtores de leite de Lavras, Passos e Divinópolis, MG, foram entrevistados com objetivo de avaliar sua percepção e atitude no controle do Rhipicephalus (Boophilus microplus. A análise da correlação multivariada entre as variáveis foi feita através de componentes principais (ACP. A percepção e atitude sobre o R. (B. microplus foram semelhantes entre os produtores, sendo que a maioria deles não tem o conhecimento básico sobre a biologia e o controle desse carrapato

  14. Percepção dos produtores de leite do município de Passos, MG, sobre o carrapato Boophilus microplus (Acari: Ixodidae, 2001 Perception of dairy farmers from Passos county, MG, Brazil, concerning the tick Boophilus microplus (acari: ixodidae, 2001

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    Christiane Maria Barcellos Magalhães da Rocha

    2006-08-01

    Full Text Available Entrevistas com 25 proprietários de rebanhos com produção diária acima de 500 litros de leite, sorteados da listagem da cooperativa de Passos/MG/Brasil, foram aplicadas para caracterizar suas percepções sobre a biologia do Boophilus microplus e suas atitudes no controle de carrapatos. A maioria desses produtores tem pelo menos o ensino médio completo e está na atividade há mais de dez anos. Os prejuízos biológicos produzidos pelos carrapatos são bem percebidos por eles; porém, não demonstraram conhecimento sobre a biologia do B. microplus e as desvantagens dos banhos carrapaticidas, principalmente com relação aos riscos toxicológicos. Esses produtores realizam controle de carrapatos sem critérios técnicos e com alta freqüência, baseando-se na avaliação subjetiva da infestação nos animais. Isto favorece o estabelecimento da resistência aos acaricidas e demonstra que a transferência de tecnologia sobre controle de carrapatos para o setor pecuário é falha.Twenty five dairy farms were randomly chosen from all farms producing more than 500 liters of milk/ day in Passos, MG, Brazil. The owners were interviewed to characterize their perceptions about the biology of B. microplus and their attitudes towards tick control. Most of the producers have a college degree and more than six year-experience in the activity. The biological damages caused by ticks are perceived by the farmers. Their tick control is performed without technical criteria and they did not show a proper knowledge on the biology of B. microplus nor on the toxicological risks of acaricides application. The results reveal a gap between the technology and farmers, favoring tick resistance to acaricides.

  15. Avaliação in vitro da ação do óleo essencial de capim limão (Cymbopogon citratus sobre o carrapato bovino Rhipicephalus (Boophilus microplus In vitro evaluation of the action of lemon grass (Cymbopogon citratus essential oil on the cattle tick Rhipicephalus (Boophilus microplus

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    F.C.C. Santos

    2012-01-01

    Full Text Available O uso indiscriminado de produtos químicos no controle do carrapato bovino constitui a principal causa do gradativo aumento do número de cepas resistentes deste parasita às bases disponíveis no mercado. A utilização de óleos essenciais e extratos vegetais é uma prática antiga no controle de carrapatos, porém só recentemente tem recebido a devida atenção dos pesquisadores. O objetivo deste experimento foi avaliar a eficácia in vitro do óleo de capim limão (Cymbopogon citratus sobre fêmeas ingurgitadas de Rhipicephalus (Boophilus microplus através do exame de biocarrapaticidograma. Foram testadas seis diluições do óleo de C. citratus (1; 5; 10; 25; 50 e 100% em uma população de carrapatos resistentes a amidínicos e piretróides sintéticos. A inibição de postura foi de 3; 23; 46; 66; 46 e 46%, a eclosão larval foi de 83; 58; 31; 0; 38 e 25% e a eficácia do tratamento foi de 32; 64; 83; 100; 88 e 82%, respectivamente. O óleo de C. citratus apresentou controle parcial do carrapato R. microplus in vitro, mesmo frente a populações resistentes a produtos químicos.The indiscriminate use of chemical products to control the cattle tick is the main cause of the gradual increase in the number of strains of this parasite that are resistant to the bases currently available in the market. The use of essential oils and plant extracts is an ancient practice for tick control; however, only recently has it received due attention by researchers. The aim of this experiment was to evaluate the in vitro efficacy of lemongrass (Cymbopogon citratus essential oil on engorged females of Rhipicephalus (Boophilus microplus through immersion test. Six concentrations of Cymbopogon citratus oil (1; 5; 10; 25; 50 and 100% were tested against a tick population resistant to synthetic formamidines and pyrethroids. The inhibition of egg-laying was 3; 23; 46; 66; 46 and 46%, the hatching was 83; 58; 31; 0; 38 and 25%, and the treatment efficacy was 32

  16. Utilización del Boophilus microplus como remedio isopático en el control del ectoparásito en el Municipio de Aguazul (Casanare

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    Francisco Javier Niño Murcia

    2005-12-01

    Full Text Available En este estudio se demostró la efectividad de un remedio isopático vía oral, para el control de la garrapata Boophilus microplus, inocuo para los animales, medio ambiente y el hombre, evitando residuos de plaguicidas en el producto final. La investigación se realizó en una finca ubicada en el municipio de Aguazul (Casanare; localizada a los 05°10’23’’ de latitud norte y 72°33’17’’ de longitud oeste desde Greenwich, altitud: 300 msnm, temperatura media: 27ÚC. Precipitación anual media: 2.441 mm. Se contó con 32 animales de doble propósito; con la propuesta adoptada por la Corporación Colombiana de Investigación Agropecuaria, CORPOICA, en cuanto al Manejo Integrado de Plagas (MIP; acerca del control ejercido con base en niveles críticos, se inició con un conteo de garrapatas, con un tamaño entre 4.5 mm y 8 mm, por un lado del cuerpo del animal; animales con más de 20 garrapatas, entraban en el proceso de investigación, se les administró el remedio isopático, el cual correspondía al grupo A, y el placebo el cual correspondió con el grupo B, durante cuatro días consecutivos. Se administraron dos potencias del remedio, la primera con nueve centésimal (9 C, la cual no tuvo ningún efecto sobre la garrapata, la segunda potencia treinta centesimal (30 C, con la cual se observaron los resultados propuestos sobre la garrapata, se hace un segundo conteo de garrapatas con los mismos tamaños para verificar la efectividad de la segunda potencia; veinticinco días después de la administración, se hizo un último conteo de garrapatas con los mismos tamaños con los cuales se partió. Se utilizó la técnica experimental de doble ciego para obtener datos más veraces. El estudio estadístico se realizó por la técnica de análisis operacional de varianza de dos factores con varias muestras por grupo; los recuentos de garrapatas se trasformaron a la expresión logarítmica: t = Log 10 (X+1, donde X es el recuento de

  17. New species of Ehrlichia isolated from Rhipicephalus (Boophilus microplus shows an ortholog of the E. canis major immunogenic glycoprotein gp36 with a new sequence of tandem repeats

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    Cruz Alejandro Cabezas

    2012-12-01

    Full Text Available Abstract Background Ehrlichia species are the etiological agents of emerging and life-threatening tick-borne human zoonoses that inflict serious and fatal infections in companion animals and livestock. The aim of this paper was to phylogeneticaly characterise a new species of Ehrlichia isolated from Rhipicephalus (Boophilus microplus from Minas Gerais, Brazil. Methods The agent was isolated from the hemolymph of Rhipicephalus (B. microplus engorged females that had been collected from naturally infested cattle in a farm in the state of Minas Gerais, Brazil. This agent was then established and cultured in IDE8 tick cells. The molecular and phylogenetic analysis was based on 16S rRNA, groEL, dsb, gltA and gp36 genes. We used the maximum likelihood method to construct the phylogenetic trees. Results The phylogenetic trees based on 16S rRNA, groEL, dsb and gltA showed that the Ehrlichia spp isolated in this study falls in a clade separated from any previously reported Ehrlichia spp. The molecular analysis of the ortholog of gp36, the major immunoreactive glycoproteins in E. canis and ortholog of the E. chaffeensis gp47, showed a unique tandem repeat of 9 amino acids (VPAASGDAQ when compared with those reported for E. canis, E. chaffeensis and the related mucin-like protein in E. ruminantium. Conclusions Based on the molecular and phylogenetic analysis of the 16S rRNA, groEL, dsb and gltA genes we concluded that this tick-derived microorganism isolated in Brazil is a new species, named E. mineirensis (UFMG-EV, with predicted novel antigenic properties in the gp36 ortholog glycoprotein. Further studies on this new Ehrlichia spp should address questions about its transmissibility by ticks and its pathogenicity for mammalian hosts.

  18. Avaliação da atividade repelente do timol, mentol, salicilato de metila e ácido salicilico sobre larvas de Boophilus microplus (Canestrini, 1887 (Acari: Ixodidae Evaluation of repellent activity of thymol, menthol, methyl salicylate and salicylic acid on Boophilus microplus larvae (Canestrini, 1887 (Acari: Ixodidae

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    A.M.S. Novelino

    2007-06-01

    Full Text Available Verificou-se a atividade repelente do timol, mentol, ácido salicílico e salicilato de metila sobre larvas de Boophilus microplus. Essas substâncias foram usadas em emulsões em dimetilsulfuxido aquoso a 1% ou solução aquosa. Para cada substância foram testadas três concentrações, 1,0%; 0,5% e 0,25%, com cinco repetições cada. Cerca de 100 larvas, com 21 dias de idade, foram inseridas na base de hastes de madeira para avaliação da repelência, a cada duas horas, totalizando 12 horas. As concentrações mais elevadas apontaram que as quatro substâncias causaram alteração no comportamento das larvas. Timol, com mortalidade de 65% e 35% de repelência e mentol e salicilato de metila, ambos com 80% de repelência foram os mais eficientes.The repellent activity of thymol, menthol, salicylic acid and methyl salicylate on Boophilus microplus larvae was studied. These substances were tested according to their solubility: emulsions in 1% aqueous dimethylsulphoxide or in pure water. Three concentrations were tested for each substance, 1.0%, 0.5% and 0.25%, with five repetitions for each. Approximately 100 larvae at 21 days of age were placed on the base of wooden sticks and then observed for repellent action every two hours, during twelve hours. The results obtained from the higher concentrations showed that the four substances caused alterations on the larvae behavior. However, thymol (65% of mortality and 35% of repellency, menthol (80% of repellency and methyl salicylate (80% of repellency were the most efficient.

  19. Integrated control of the southern cattle fever tick, Rhipicephalus (Boophilus) microplus, in Puerto Rico using new and alternative products

    Science.gov (United States)

    Puerto Rico (PR) is plagued by the southern cattle fever tick (SCFT), Rhipicephalus microplus, which is considered the most economically important external parasite of livestock worldwide. A research coalition involving the livestock industry in PR, the PR Department of Agriculture (PR-DA), and the...

  20. Avaliação in vitro da eficácia de acaricidas sobre Boophilus microplus (Canestrini, 1887 (Acari: Ixodidae de bovinos no município de Ilhéus, Bahia, Brasil In vitro valuation of acaricides efficiency to Boophilus microplus (Canestrini, 1887 (Acari: Ixodidae from bovines at the region of Ilhéus, Bahia, Brazil

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    Dunezeu Alves Campos Júnior

    2005-12-01

    Full Text Available O carrapato Boophilus microplus é a espécie de maior distribuição geográfica e importância econômica para os países produtores de bovinos em áreas tropicais e sub-tropicais do planeta. No Brasil, a Região Nordeste apresenta algumas áreas mais favoráveis para as infestações do gado. O controle químico ainda é a forma mais eficaz de combate deste ectoparasita, mas o manejo inadequado dos acaricidas tem contribuído com o aparecimento de resistência de populações aos produtos disponíveis no mercado. O município de Ilhéus, na Região Cacaueira da Bahia, vem incrementando sua atividade pecuária em substituição à lavoura cacaueira devastada. Foram realizados 30 testes de imersão in vitro (biocarrapaticidogramas com fêmeas ingurgitadas de B. microplus colhidas em propriedades rurais aleatoriamente selecionadas num grupo de 96 entrevistadas na região. O estudo revelou a existência de resistência ou sensibilidade de populações de B. microplus frente aos carrapaticidas de contato mais utilizados nas propriedades de exploração pecuária da região de Ilhéus. Os quatro carrapaticidas testados apresentaram as seguintes eficiências médias: Amitraz - 30,95%; Deltametrina - 65,04%; Cipermetrina / diclorvos - 75,73%; e Triclorfon / coumaphos / cyfluthrin - 75,13%.The tick Boophilus microplus is the species with the greatest geographical distribution and economic importance for the countries situated at tropical and sub-tropical zones of the planet. In Brazil, the Northwest Region is showed as the most favorable to the cattle infestation. Chemical control is an efficient control method employed, but the inadequate handling of acaricides contributed for to the onset of resistant ticks to the available acaricides in the market. The county of Ilhéus, at the Cocoa's Region from Bahia, has been increasing the cattle activity instead of the devastated cocoa's plantations. Between April and September 2000, in vitro imersion tests

  1. Detección de resistencia a los acaricidas en la garrapata del ganado Boophilus microplus mediante análisis de zimogramas (Acaricide resistance detection in the cattle tick Boophilus microplus by zymograms analysis).

    OpenAIRE

    Miranda, Miranda, Estefan; Osorio, Miranda Jorge; Cossío, Bayúgar, Raquel

    2005-01-01

    La identificación de resistencia a los productos acaricidas en la garrapata B. microplus, se hace mediante un complicado bioensayo, que requiere garrapatas de referencia y de campo cultivadas sobre bovinos vivos y restringidos durante semanas. Con el fin de evaluar una posible alternativa diagnóstica, se hicieron ensayos enzimáticos en geles de poliacrilamida-SDS, usando extractos de larvas de garrapatas provenientes de cuatro cepas de referencia con diferentes niveles de resistencia y suscep...

  2. Characterization of the pyrethroid resistance profile of Rhipicephalus (Boophilus) microplus populations from the states of Rio Grande do Sul and Mato Grosso do Sul, Brazil.

    Science.gov (United States)

    Mendes, Márcia Cristina; Duarte, Fernanda Calvo; Martins, João Ricardo; Klafke, Guilherme Marcondes; Fiorini, Leonardo Costa; de Barros, Antônio Thadeu Medeiros

    2013-01-01

    Cattle ticks Rhipicephalus (Boophilus) microplus are mainly controlled in Brazil by means of acaricide products, without any official policies in this regard. Acaricides continue to be sold indiscriminately, and this has contributed towards making the problem of resistance widespread, thus making diagnosis and monitoring of tick resistance essential. Here, bioassays (larval packet test) were performed on tick populations from the states of Rio Grande do Sul and Mato Grosso do Sul regarding their susceptibility to cypermethrin, deltamethrin and flumethrin. All the tick samples tested showed resistance to cypermethrin (10) (resistance factor (RF) ranging from 5.6 to 80.3) and deltamethrin (10) (RF ranging from 2.4 to 83.1). Six out of eight populations were resistant to flumethrin (RF ranging from 3.8 to 8.2). PCR molecular analyses did not show any T2134A mutations in the voltage-gated sodium channel gene, in any of the sampled populations. The results from this study highlight the critical status of resistance of the cattle tick to synthetic pyrethroids in the regions studied. Further studies are needed to identify the mechanisms responsible for the resistant phenotypes observed in the bioassays. This was the first detection of flumethrin resistance in Brazil. PMID:24142169

  3. 3β-O-Tigloylmelianol from Guarea kunthiana: A New Potential Agent to Control Rhipicephalus (Boophilus microplus, a Cattle Tick of Veterinary Significance

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    Carlos Henrique Miguita

    2014-12-01

    Full Text Available Chemical investigation of Guarea kunthiana fruits, guided by their effect on the reproductive cycle of engorged females of the cattle tick Rhipicephalus (Boophilus microplus—a major economic problem to the livestock industry worldwide—led to isolation of 3β-O-tigloylmelianol, a new protolimonoid, from the bioactive hexane phase obtained by partitioning the crude ethanol extract. An adult immersion test was performed. The compound strongly inhibited egg-laying and hatchability (99.2% effectiveness at a 0.01% concentration. Melianone, isolated from the same phase, yielded unremarkable results in the adult immersion test. From the dichloromethane phase, melianol, melianodiol, meliantriol, and a new protolimonoid, 3β-O-tigloylmeliantriol, were isolated, all of which, in the same manner as melianone, exhibited unremarkable results in the test. The structures of new and known compounds were mostly established by 1D- and 2D-NMR analyses and mass spectrometry data. This is the first report on the bioactivity of protolimonoids on the reproductive cycle of engorged females of R. (B. microplus. 3β-O-Tigloylmelianol proved a promising candidate for the development of a biocontrol agent against the cattle tick investigated, as an alternative to environmentally hazardous synthetic acaricides.

  4. [Morphologic characterization and biological aspects of evolutive forms of Babesia bigemina (Smith and Kilborne, 1893) (Protozoa: Babesiidae) in Boophilus microplus (Canestrini, 1887)].

    Science.gov (United States)

    Barreira, Jairo D; Rossi, Maria Inês D; da Silva, Gil Vicente O; Pires, Fabiano A; Massard, Carlos L

    2005-01-01

    The development of Babesia bigemina in Boophilus microplus were studied in experimental conditions, using crossed-breed bovine from free-area of these parasites. Stages of the hemoparasites were observed in the tick vector, starting from the infected red-blood cells observed in the gut of engorged females, from the first 24 hours after detachment to the emergence of sporokinets in the larvas. In the period from 24 to 48 hours after detachment of the engorged females (DEF), the presence of some infected red-blood cells was verified, beside the occurrence of ray bodies and of vermiculars forms, known as oocynets. Since 72 hours after the DEF, the of okinets presence was observed in the cytoplasm of the epithelium cells besides of great sporokinets number in development. At same period, the presence of sporokinets of B. bigemina in the hemolymph samples was observed inside the hemocytes. After the fourth day of incubation beside the presence of the sporokinets was also verified in the Malpighi's tubes and ovaries. As well as in the ticks eggs from the sporokinets were also observed ticks eggs from the fourty day after the natural detachment of the engorged females of the host. PMID:16153336

  5. A theoretical analysis of codon adaptation index of the Boophilus microplus bm86 gene directed to the optimization of a DNA vaccine.

    Science.gov (United States)

    Ruiz, Lina María; Armengol, Gemma; Habeych, Edwin; Orduz, Sergio

    2006-04-21

    DNA vaccines utilize host cell molecules for gene transcription and translation to proteins, and the interspecific difference of codon usage is one of the major obstacles for effective induction of specific and strong immune response. In an attempt to improve codon usage effects of DNA vaccine on protein expression, a quantitative study was conducted to clarify the relationship of codon usage in the tick gene bm86 and its potential expression in bovine cells. The calculated relative synonymous codon usage (RSCU) and codon adaptation index (CAI) values of bm86 from Boophilus microplus and a set of 14 highly expressed genes from Bos taurus indicated that some codons utilized frequently in bm86 are rarely used in B. taurus genes and vice versa. The different translational efficiencies obtained suggested that after DNA vaccination using the wild bm86 gene, the protein Bm86 would be expressed in bovines, but it would not be the optimum sequence. However, using the codon-optimized bm86 gene to bovines, whose sequence was theoretically designed, would probably improve the level of the immune response generated against ticks. PMID:16171828

  6. [Elaboration and evaluation of a candidate to the DNA vaccine using synthetic genes derived from the peptídeo SBm7462 against the carrapato Rhiphicephalus (Boophilus) microplus].

    Science.gov (United States)

    Medeiros, Carla L; Mendonça, Bianca G; Tavares, Larissa C; Girão, Flávia A; Sossai, Sidimar; Peconick, Ana P; Carvalho, Gabriel D; Patarroyo, Joaquín H

    2008-09-01

    Rhiphicephalus (Boophilus) microplus is one of the most important arthropods in veterinary medicine due economic losses and health problems caused in cattle production. The vaccination represents optimum method evaluated with effective cost to prevent economic losses and to increase the duration and quality of life of the production animals. A synthetic peptide, SBm 7462, derived from Bm86, has been shown great results in control of ticks. The construction and synthesis of one nucleotide sequence based on this peptide might be useful for design a DNA vaccine that has many advances than peptide vaccine. A gene, called seq1, was constructed with a three repetition of nucleotide sequence of SBm 7462. It was cloned into a pCIneo vector expression in mammals and injected in BALB/c mouse. When mice were inoculated with the expression cassette they did not response in ELISA. They elevated antibody titles only when vaccinated with the synthetic peptide SBm7462®. And, the best titles of immunoglobulins were seen when the SBm7462® was administered subcutaneously. PMID:20059811

  7. Determinação da CL90 e TL90 do isolado IBCB66 de Beauveria bassiana (Ascomycetes: Clavicipitaceae para o controle de Rhipicephalus (Boophilus microplus (Acari: Ixodidae Determination of LC 90 and LT 90 of IBCB66 Beauveria bassiana (Ascomycetes: Clavicipitaceae isolate for Rhipicephalus (Boophilus microplus (Acari: Ixodidae control

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    Barci Leila A. G.

    2009-12-01

    Full Text Available O presente trabalho teve por objetivo avaliar a patogenicidade e a virulência do isolado IBCB66 de Beauveria bassiana para larvas de Rhipicephalus (Boophilus microplus. O isolado IBCB66 foi utilizado como padrão, com a finalidade de determinar a CL50 (Concentração Letal, CL90, TL50 (Tempo Letal e TL90. O isolado IBCB66 foi testado em seis concentrações diferentes (5 × 10(6, 10(7, 5 × 10(7, 10(8, 5 × 10(8 e 10(9 para determinar a porcentagem de mortalidade. A mortalidade total de larvas foi observada 18 dias após o início do teste no grupo tratado com 5 × 10(9 conídios.mL-1. A análise de Probit dos dados consignados apontou a CL50 e CL90 concentrações de 3 × 10(7 e 5 × 10(8 conídios.mL-1 e para TL50 e TL90, foram 10 e 16 dias, respectivamente.The objective of this research was to evaluate the pathogenicity and the virulence of the IBCB66 isolate of Beauveria bassiana on infected larvae of Rhipicephalus (Boophilus microplus. The IBCB66 fungus strain was used as standard isolates of B. bassiana against R. (B. microplus larvae. The larval bioassay tests using the IBCB66 isolate were carried out to determine the (Lethal Concentration LC50, LC90, (Lethal Time LT50 and LT90. The IBCB66 fungus strain was tested at six different concentrations (5 × 10(6, 10(7, 5 × 10(7, 10(8, 5 × 10(8 and 10(9 conidia.mL-1 to determine the percentage of larval mortality. In addition, a Probit analysis was also performed. Total larval mortality was observed eighteen days after the beginning of the test in the group treated with 5 × 10(9 conidia.mL-1. The LC50 and LC90 were 3 × 10(7 and 5 × 10(8 respectively and the LT50 and LT90 were 10 and 16 days.

  8. Expression and secretion in Aspergillus nidulans and Aspergillus niger of a cell surface glycoprotein from the cattle tick, Boophilus microplus, by using the fungal amdS promoter system.

    OpenAIRE

    Turnbull, I F; Smith, D R; Sharp, P. J.; Cobon, G S; Hynes, M J

    1990-01-01

    A cell surface glycoprotein (Bm86) from cells of the digestive tract of the cattle tick Boophilus microplus, which has been shown to elicit a protective immunological response in vaccinated cattle, was expressed and secreted in the filamentous fungi Aspergillus nidulans and Aspergillus niger by using the fungal amdS promoter system. The cloned gene coded for the Bm86 secretory signal and all of the Bm86 mature polypeptide except for the hydrophobic carboxy-terminal segment. High levels of Bm8...

  9. Evaluation of antibodies production against Borrelia burgdorferi in cattle submitted to rBm86 protein Boophilus microplus tick immunization and associated challenges influence Avaliação da produção de anticorpos anti Borrelia burgdorferi em bovinos submetidos à imunização com proteína rBm86 de carrapato Boophilus microplus e influência dos desafios associados

    OpenAIRE

    Márcia Mayumi Ishikawa; Adivaldo Henrique Fonseca; Natalino Hajime Yoshinari; Ana Luiza Alves Rosa Osório

    2003-01-01

    IgG antibodies production against Borrelia burgdorferi in immunized cattle with rBm86 protein from Boophilus microplus was evaluated as well as the influence of the association between immunizations and stress through indirect ELISA test during one year. In the present study there was no influence of the isolated challenged used on the production of IgG antibodies against B. burgdorferi. The rBm86 immunogen did not cause significant oscillation in the production of IgG antibodies against B. b...

  10. Acaricide activity of leaves extracts of Sambucus australis Schltdl. (Caprifoliaceae at 2% on engorged females of Rhipicephalus (Boophilus microplus Atividade acaricida de extratos de folhas de Sambucus australis Schltdl (Caprifoliaceae a 2% sobre teleóginas de Rhipicephalus (Boophilus microplus

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    Felipe da Silva Krawczak

    2011-12-01

    Full Text Available Parasite infections caused by Rhipicephalus (Boophilus microplus are responsible for the most of economic losses in producing-cattle countries in tropical and subtropical areas. Indiscriminate uses of chemical acaricides have contributed with the appearance of tick resistance to many drugs available in the marketplace, and it is a serious problem in the tick control. Flowers of Sambucus australis (South America, called "sabugueiro-from-Brazil", are used on infusions or decoctions forms in the folk medicine with diuretic, antipyretic, anti-inflammatory, and laxative purpose, also employed for treating respiratory diseases in human. The main goal of this study was to evaluate in vitro potential of S. australis leaves extracts as an acaricide agent. Ethanol extract at 70% has been dehydrated and a fraction was suspended in 70% ethanol or in distillated water at final concentration of 2% (0.2mg-1. Using the immersion test of engorged females the efficiency results were obtained in 34% and 66% with the leaves extract diluted in water and 70% ethanol, respectively. This study is the first report on acaricidal activity of S. australis against cattle tick. Further studies to determine the active metabolites in different stages of S. australis could aid to identify suitable extracts to be tested in the R. (B. microplus control.A infestação por Rhipicephalus (Boophilus microplus é responsável por grandes perdas econômicas em países produtores de bovinos nas áreas tropicais e subtropicais. Usos indiscriminados de acaricidas químicos têm contribuído para o aparecimento da resistência dos ixodídeos a múltiplas drogas, representando um sério problema no controle de carrapatos. As flores da planta Sambucus australis, conhecidas pelo nome popular de sabugueiro do Brasil, são usadas, na forma de infusão ou emplastros, na medicina popular como diurético, antipirético, antiinflamatório e laxativo; também empregado no tratamento de doen

  11. New histochemical and morphological findings in the female genital tract of Boophilus microplus (Acari, Ixodidae: an attempt toward the elucidation of fertilization in ticks Novas características histoquímicas e morfológicas no trato genital feminino de Boophilus microplus (Acari: Ixodidae: uma tentativa para a elucidação da fertilização nos carrapatos

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    Casimiro García-Fernández

    2005-09-01

    Full Text Available At present not only is the site of fertilization in ticks still unknown but it is also unclear as to how this mystery can be solved. Signs of fertilization can be observed throughout the female genital tract and these can be clues for the elucidation of the unsolved questions relating to ticks fertilization. In Boophilus microplus (Canestrini, 1887 the most important signs are the following: the final eversion of the acrosomal canal in females ready for oviposition; the presence of small tubules, resembling the subplasmalemal process of the spermatozoon between the oviduct cells; budding nuclei throughout the female genital tract; and the two Feulgen and DAPI positive areas in the oocyte at vitelogenesis. These morphological characteristics suggest that fertilization takes place in the internal cylinder which extends from the uterus to the ovary itself.Até o momento, não só o lugar da fertilização em carrapatos é desconhecido, mas também não é claro como este mistério possa ser esclarecido. Sinais de fertilização podem ser observados ao longo do trato genital feminino e estes podem ser pistas para a elucidação das questões relacionadas à fertilização em ácaros. Em Boophilus microplus (Canestrini, 1887, os sinais mais importantes são os seguintes: a eversão final do canal acrossômico em fêmeas prestes à oviposição; a presença de pequenos túbulos assemelhando-se a processos subplasmalêmicos dos espermatozóides entre as células do oviduto; brotamentos nucleares ao longo do trato genital feminino e as duas áreas Feulgen e DAPI positivas nos ovócitos em processo de vitelogênese. Estas características morfológicas sugerem que a fertilização ocorra no cilindro interno, o qual se estende desde o útero até o ovário inclusive.

  12. Rusa deer (Cervus timorensis) as a host for the cattle tick (Boophilus microplus) in Papua New Guinea.

    Science.gov (United States)

    Owen, I L

    1977-04-01

    The rusa deer (Cervus timorensis) is more resistant to the cattle tick (Boophlilus microplus) than are Britsh breed cattle in Papua New Guinea. The average yield of replete female ticks from deer was 1.6% (0.3-3.2%) as compared to 11.2% (3.4-23.1%) from calves. Ticks from deer were more slender, lighter in weight and produced fewer eggs (mean 1,800) than did ticks from calves (mean 2,200) but the deer was shown to be an effective host. A cervid population can maintain a tick population in the absence of bovine hosts thus presenting an important factor in eradication programs. Nutritional stress appears to result in a higher seasonal prevalence of infestation amongst males and non-pregnant females. PMID:864854

  13. INFLUÊNCIA DO PESO INICIAL E DA ESTAÇÃO DO ANO NA CONVERSÃO EM OVOS DE FÊMEAS DE Boophilus microplus (ACARI: IXODIDAE

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    Abraão Garcia Gomes

    2006-10-01

    Full Text Available Este trabalho objetivou avaliar a influência do peso inicial da fêmea e da estação do ano na conversão em ovos de Boophilus microplus. O índice de eficiência reprodutiva (IER de 411 fêmeas pesando entre 31 e 360 mg foi correlacionado com seu peso inicial. Para avaliar a influência das diferentes estações do ano neste parâmetro biológico, dez fêmeas ingurgitadas de B. microplus pesando acima de 150 mg foram colhidas, a cada duas semanas, e mantidas em condições climáticas controladas até a determinação do IER. Uma relação curvilinear foi observada entre o peso das fêmeas e o IER. Fêmeas pesando entre 151 e 360 mg tiveram IER’s mais altos (variando de 44,9% a 51,4% do que aquelas mais leves, as quais apresentaram uma menor capacidade de conversão em ovos (variando de 31,4% a 39,0%. Foi observado que a capacidade de as fêmeas converterem o peso em ovos variou sazonalmente. Os mais altos IER foram observados no período seco, de abril a setembro (47,6% a 58,3%, do que no período chuvoso, de outubro a março (40,2% a 43,6% (P<0,05. PALAVRAS-CHAVE: Boophilus microplus, biologia, conversão em ovos, bovinos.

  14. Population dynamics and evaluation of the partial selective treatment of crossbreed steers naturally infested with Rhipicephalus (Boophilus) microplus in a herd from the state of Minas Gerais in Brazil.

    Science.gov (United States)

    Gomes, Lucas Vinicius Costa; Lopes, Welber Daniel Zanetti; Teixeira, Weslen Fabricio Pires; Maciel, Willian Giquelin; Cruz, Breno Cayeiro; Felippelli, Gustavo; Buzzulini, Carolina; Soares, Vando Edésio; de Melo, Daniel Pacheco; Bichuette, Murilo Abud; Gonçalves Junior, Geraldo; da Costa, Alvimar José

    2016-04-15

    The present study aimed to evaluate the population dynamics of Rhipicephalus (Boophilus) microplus over a period of 13 months on a rural property located in the state of Minas Gerais in southeastern Brazil. Animals were treated for ticks indoors by whole body spraying when R. (B.) microplus had an average count equal or more than 30 ticks. The study also evaluated the possibility of a partial selective treatment for bovines to control R. (B.) microplus in which only a percentage of the population would be treated (specifically those bovines with tick counts of ≥20. Moreover, we examined the percentage of the population of R. (B.) microplus present on experimental bovines that did not come into contact with the chemical compounds used in the partial selective treatment. We concluded that in this particular region of Brazil, the crossbreed steers support up to five R. (B.) microplus generations per year and that the number of generations was primarily affected by the pluviometric precipitation. We sprayed the bovines with chemicals seven times during the course of the study. The results of the partial selective treatment method revealed that during the rainy and the dry periods, 42.1% to 60.0% and 61.9% to 79.2% of the animals, respectively, fulfilled the criteria to receive a chemical treatment to reduce the number of cattle ticks. In consideration of the need to slow the development of tick resistance with the chemical compounds used in the spraying treatment, the results showed that the percentage of animals that did not require treatment is not relevant. This was evidenced by the result that bovines that presented tick counts of ≥20 during the dry and rainy periods represented 91.5% and 90.6% of the total recorded R. (B.) microplus populations, respectively. Only 8.7% of the tick population remained free from exposure to acaricides during the 13 months of the study, which is an important point when considering the adoption of the partial selective treatment

  15. Population dynamics and evaluation of the partial selective treatment of crossbreed steers naturally infested with Rhipicephalus (Boophilus) microplus in a herd from the state of Minas Gerais in Brazil.

    Science.gov (United States)

    Gomes, Lucas Vinicius Costa; Lopes, Welber Daniel Zanetti; Teixeira, Weslen Fabricio Pires; Maciel, Willian Giquelin; Cruz, Breno Cayeiro; Felippelli, Gustavo; Buzzulini, Carolina; Soares, Vando Edésio; de Melo, Daniel Pacheco; Bichuette, Murilo Abud; Gonçalves Junior, Geraldo; da Costa, Alvimar José

    2016-04-15

    The present study aimed to evaluate the population dynamics of Rhipicephalus (Boophilus) microplus over a period of 13 months on a rural property located in the state of Minas Gerais in southeastern Brazil. Animals were treated for ticks indoors by whole body spraying when R. (B.) microplus had an average count equal or more than 30 ticks. The study also evaluated the possibility of a partial selective treatment for bovines to control R. (B.) microplus in which only a percentage of the population would be treated (specifically those bovines with tick counts of ≥20. Moreover, we examined the percentage of the population of R. (B.) microplus present on experimental bovines that did not come into contact with the chemical compounds used in the partial selective treatment. We concluded that in this particular region of Brazil, the crossbreed steers support up to five R. (B.) microplus generations per year and that the number of generations was primarily affected by the pluviometric precipitation. We sprayed the bovines with chemicals seven times during the course of the study. The results of the partial selective treatment method revealed that during the rainy and the dry periods, 42.1% to 60.0% and 61.9% to 79.2% of the animals, respectively, fulfilled the criteria to receive a chemical treatment to reduce the number of cattle ticks. In consideration of the need to slow the development of tick resistance with the chemical compounds used in the spraying treatment, the results showed that the percentage of animals that did not require treatment is not relevant. This was evidenced by the result that bovines that presented tick counts of ≥20 during the dry and rainy periods represented 91.5% and 90.6% of the total recorded R. (B.) microplus populations, respectively. Only 8.7% of the tick population remained free from exposure to acaricides during the 13 months of the study, which is an important point when considering the adoption of the partial selective treatment

  16. Effect of different concentrations of citronella oil and tincture on reproductive parameters of Rhipicephalus (Boophilus microplus teleoginesEfeito de diferentes concentrações de óleo e tintura de citronela sobre os parâmetros reprodutivos de teleóginas de Rhipicephalus (Boophilus microplus

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    Fernanda Silveira Flores Vogel

    2012-06-01

    Full Text Available The tick Rhipicephalus (Boophilus microplus is the most important ectoparasite in cattle rising, and it is responsible for severe economic losses. Parasite control is based on chemicals, which are used indiscriminately and result in effectiveness reduction of these compounds. In order to delay the onset of parasite resistance, some alternative methods are being researched, including herbal medicine. The aim of this experiment was to evaluate the in vitro efficacy of citronella (Cymbopogon nardus oil and tincture on R. (B microplus by the engorged female immersion test. Four oil concentrations were tested (1; 25; 50; 100% and the inhibition of oviposition were 16; 40; 53; 73%, egg hatch were 28; 16; 23; 6% and the effectiveness were 78; 100; 86; 98%, respectively. The gradual rise of the inhibition of oviposition and low egg hatch had a positive influence in the effectiveness of treatment. The solution at 1% of citronella oil had a partial control of the teleogines and the solution at 25% had 100% of effectiveness. Six dilutions of the tincture (1; 5; 10; 25; 50; 100% were tested and the inhibition of oviposition were 10; 63; 80; 83; 86; 96%, egg hatch were 91; 31; 6; 26; 0; 0% and the effectiveness were 23; 93; 94; 97; 100; 100%, respectively. Most of the treatments with the citronella tincture had inhibition of oviposition higher than 80% and low egg hatch rate. The tincture at 5% had similar efficacy compared to the groups with higher concentrations. A significant association between the oil and tincture of citronella and the treatment effectiveness was observed in the statistical evaluation. It is possible to conclude that both the oil and the tincture of citronella had negative influence in the reproductive parameters of R. (B microplus. O carrapato Rhipicephalus (Boophilus microplus é o ectoparasito mais importante em áreas de exploração pecuária, sendo responsável por severas perdas econômicas. O controle deste parasito é feito

  17. Role of Rusa deer Cervus timorensis russa in the cycle of the cattle tick Boophilus microplus in New Caledonia.

    Science.gov (United States)

    Barré, N; Bianchi, M; Chardonnet, L

    2001-01-01

    Two field experiments were conducted to evaluate the efficiency of Rusa deer in the development of the cattle tick Boaphilus microplus in comparison with that of steers in the same pastures and under the same conditions of infestation. No difference was noted between a mixed steer/deer herd and a pure steer or pure deer herd in the infestation pattern of each host, suggesting that attachment to the alternative host is mechanical and not affected by the simultaneous presence of the primary host on the pasture. Deer are capable of producing engorged viable females, with weight and reproductive performances similar to or even better than females fed on steers. For moderate levels (1 million larvae per hectare) and high levels (32 million larvae per hectare) of pasture infestation, tick burdens on steers were not very different (e.g. average 1,911 and 2,681 ticks per m2 skin, respectively, on day 24). This may be because of saturation of steer skin sites at the moderate larval dose. Deer harboured 2.7-33 times fewer ticks than steers and produce no engorged females at the moderate larval level and 32 times fewer engorged females than steers at the high larval level. Infestation of deer was dose-dependent with averages of 12 and 399 ticks per m2 skin on day 25 at the moderate and high larval levels, respectively. At a high infestation level of the environment, Rusa deer may contribute, but to a limited extent, to infestation of pastures and, consequently, of cattle. However, their role in sustaining a viable tick population requires further investigation. PMID:11508531

  18. Caracterização do controle de Haematobia irritans e Rhipicephalus (Boophilus microplus no Triângulo Mineiro e Alto Paranaíba, Minas Gerais

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    Luísa N. Domingues

    2012-12-01

    Full Text Available O controle eficaz de Haematobia irritans (mosca-dos-chifres e Rhipicephalus (Boophilus microplus (carrapato-do-boi é um fator crucial à maior rentabilidade da pecuária brasileira, porém ainda constitui-se um desafio. Um maior conhecimento das práticas adotadas no combate destes parasitos faz-se necessário para que se possam estruturar estratégias de controle mais próximas da realidade do produtor rural e mais fáceis de serem executadas. Este estudo caracterizou, através de entrevistas, as práticas adotadas no controle desses ectoparasitos em 23 propriedades da mesorregião do Triângulo Mineiro e Alto Paranaíba, Minas Gerais. A maioria dos entrevistados reconheceu a importância desses parasitos para a atividade pecuária, entretanto, diversos problemas relativos ao controle parasitário foram observados. O controle da mosca-dos-chifres e do carrapato-do-boi era uma prática rotineira em, respectivamente, 17,4% e 95,7% das propriedades, geralmente realizado em função de elevado grau de infestação dos animais. Mais de seis aplicações de ectoparasiticidas eram realizadas por ano em todas as propriedades que empregavam tratamentos para o controle da mosca e em 76,5% daquelas que combatiam o carrapato. Os produtos eram aplicados principalmente com bombas costais manuais (63,6% e sem a contenção dos animais em 45,5% das propriedades. A diluição dos produtos segundo recomendações dos fabricantes era realizada por 45,4% dos entrevistados, porém, 63,6% aplicavam um volume de solução por animal menor do que o tecnicamente recomendado. Utilizava-se principalmente a associação de piretróides e organofosforados para o controle de ambos os parasitos. Apesar de utilizar rotineiramente ectoparasiticidas, o uso de equipamento de proteção individual (EPI não era comum entre os entrevistados. A maioria dos entrevistados conhecia algumas características epidemiológicas dos parasitos, entretanto, o controle parasitário adotado na

  19. Ten years later: Evaluation of the effectiveness of 12.5% amitraz against a field population of Rhipicephalus (Boophilus) microplus using field studies, artificial infestation (Stall tests) and adult immersion tests.

    Science.gov (United States)

    Maciel, Willian Giquelin; Lopes, Welber Daniel Zanetti; Cruz, Breno Cayeiro; Gomes, Lucas Vinicius Costa; Teixeira, Weslen Fabrício Pires; Buzzulini, Carolina; Bichuette, Murilo Abud; Campos, Gabriel Pimentel; Felippelli, Gustavo; Soares, Vando Edésio; de Oliveira, Gilson Pereira; da Costa, Alvimar José

    2015-12-15

    Using field trials, artificial infestations (Stall tests) and in vitro adult immersion tests, the present study evaluated the acaricidal efficacy of 12.5% amitraz administered via whole body spraying against a Rhipicephalus (Boophilus) microplus population that did not have any contact with chemical products belonging to this acaricide family for 10 years (approximately 40 generations). Two natural infestation trials, two artificial infestation trials (Stall tests) and two adult immersion tests were performed in two different stages in 2005 and 2015. Between 2002 and 2015, the bovine herd of this property was formed by approximately 450 animals from the Simmental breed that were divided into nine paddocks formed by Cynodon dactylon (L.) Pers. For the natural infestation experiments in 2005 and 2015, we selected nearly 70 animals naturally infested with ticks from the same herd that belonged to the "São Paulo" farm located in São José do Rio Pardo, São Paulo, Brazil. Field studies were performed in the same paddock (9). To evaluate anti-R. (B.) microplus activity in the artificially infested cattle (Stall tests) and adult immersion tests, two experiments of each methodology were performed at CPPAR (the Center of Research in Animal Health located on the FCAV/UNESP campus in Jaboticabal, São Paulo, Brazil) in 2005 and 2015. R. (B.) microplus used in the artificial infestation, and adult immersion test experiments were obtained from paddocks 1-9 in 2005 and 2015 from the commercial farm where the field studies were performed. Based on the obtained results, it was possible to conclude that amitraz use in rotation with pyrethroids every 28 days for three consecutive years (2002-2004) previous to the beginning of the first trial (2005) was sufficient to generate a R. (B.) microplus strain resistant to amitraz. Moreover, using field trials, artificial infestations (Stall tests) and adult immersion tests, we verified that 40 generations of the tick species with no

  20. AVALIAÇÃO IN VITRO DA AÇÃO DE ACARICIDAS SOBRE Rhipicephalus (Boophilus microplus CANESTRINI, 1887 (ACARI: IXODIDAE DE BOVINOS LEITEIROS NO MUNICÍPIO DE ITAMARAJU, BAHIA, BRASIL

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    Fernando Henrique Spagnol

    2010-10-01

    Full Text Available As many tick populations of Rhipicephalus (Boophilus microplus can be resistant to drugs in the municipality of Itamaraju,Bahia, Brazil, an in vitro immersion test was carried out, from January to November 2008, in ticks from 22 dairy farms using the nine most used acaricides in the market. Fipronil had 99% efficacy, Chlorpyriphos+Cypermethrin high-cis 92%, Amitraz+Chlorpyriphos 90.7%, Diclorvos+Chlorpyriphos 81.4%, Cypermethrin+Chlorpyriphos+Citronelol 49.2%, Amitraz 49.0%, Cypermethrin+Ethion 39.9%, Deltamethrin 33.9%, Cypermethrin 21.1%. There was a range from one to five efficient acaricides (≥ 95% in each property. The results show that there is a wrong use of acaricides by the farmers and a high degree of resistance by ticks.

  1. Análise da eficácia de acaricidas sobre o carrapato Boophilus microplus, durante a última década, na região sul do Rio Grande do Sul Acaricids efficacy analysis on Boophilus microplus tick, in the last decade in the southern of Rio Grande do Sul

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    Nara Amélia Farias

    2008-09-01

    Full Text Available A região sul do Rio Grande do Sul caracteriza-se por uma bovinocultura com predomínio de raças européias, tanto para produção de carne, quanto de leite. Essa região é considerada área marginal de ocorrência do carrapato Boophilus microplus, cujo parasitismo ocorre entre final de setembro e meados de maio devido às baixas temperaturas do inverno. No entanto, as perdas causadas por esse parasito são elevadas, o que tem sido agravadas pela seleção de populações de carrapatos resistentes aos acaricidas. O presente trabalho teve como objetivo estudar a situação de sensibilidade/resistência do carrapato bovino, assim como a dinâmica de uso dos diferentes grupos acaricidas disponíveis no mercado, na região sul do Rio Grande do Sul, na última década. Durante o período foram avaliadas amostras de carrapatos provenientes de 124 propriedades, de 14 municípios da região. Em cada propriedade foram coletadas teleóginas e informações relativas ao manejo. No Laboratório de Parasitologia do Instituto de Biologia da UFPel, foi realizado teste de imersão de teleóginas. Observou-se que durante o primeiro triênio os produtos mais utilizados eram à base de piretróide, determinando uma seleção de populações resistentes a esse princípio ativo. No terceiro triênio os produtos a base de amitraz dominaram o mercado, ocorrendo também seleção de populações resistentes. No primeiro triênio, todas as populações de carrapato analisadas eram sensíveis ao amitraz (índice de eficácia = 95%, enquanto que, ao final do estudo, no terceiro triênio, esse índice de eficácia foi detectado em apenas 79% das populações estudadas. Foram detectadas falhas de manejo na região, como número de aplicação superior a seis por ano, aplicação de acaricida somente quando visualizadas as formas adultas e uso exclusivo de acaricidas para o controle do carrapato, que predispõem a seleção de populações resistentes.In the southern

  2. Evaluation of antibodies production against Borrelia burgdorferi in cattle submitted to rBm86 protein Boophilus microplus tick immunization and associated challenges influence Avaliação da produção de anticorpos anti Borrelia burgdorferi em bovinos submetidos à imunização com proteína rBm86 de carrapato Boophilus microplus e influência dos desafios associados

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    Márcia Mayumi Ishikawa

    2003-11-01

    Full Text Available IgG antibodies production against Borrelia burgdorferi in immunized cattle with rBm86 protein from Boophilus microplus was evaluated as well as the influence of the association between immunizations and stress through indirect ELISA test during one year. In the present study there was no influence of the isolated challenged used on the production of IgG antibodies against B. burgdorferi. The rBm86 immunogen did not cause significant oscillation in the production of IgG antibodies against B. burgdorferi capable to interfere in the serological results for Lyme Borreliosis in cattle. This study demonstrated the possibility of transitory changes in the production of antibodies after the association of vaccine stimuli and stress, emphasizing the necessity of serological studies combined with epidemiological and management data.Avaliou-se a produção de anticorpos da classe Ig-G anti Borrelia burgdorferi em bovinos imunizados com proteína recombinante Bm86 de Boophilus microplus, assim como a influência de imunizações e estresse associados por meio do teste ELISA indireto no período de um ano. Não houve interferência na produção de anticorpos IgG anti B. burgdorferi pelos desafios utilizados isoladamente no presente estudo. O imunógeno rBm86 não causou oscilações significantes na produção de anticorpos IgG anti B. burgdorferi capazes de interferir nos resultados sorológicos para Borreliose de Lyme em bovinos. O estudo demonstrou a possibilidade de alterações transitórias na produção de anticorpos após estímulos vacinais e de estresse associados, ressaltando a necessidade de estudos sorológicos em conjunto a dados epidemiológicos e de manejo.

  3. Effect of vaccination with a recombinant Bm86 antigen preparation on natural infestations of Boophilus microplus in grazing dairy and beef pure and cross-bred cattle in Brazil.

    Science.gov (United States)

    Rodríguez, M; Massard, C L; da Fonseca, A H; Ramos, N F; Machado, H; Labarta, V; de la Fuente, J

    1995-12-01

    Current methods for the control of the cattle tick Boophilus microplus infestations are not effective and the parasite remains a serious problem for the cattle industry in tropical and sub-tropical areas. Recent advances have introduced the possibility for the immunological control of the parasite through the use of recombinant vaccines. Recently, it was shown that the recombinant vaccine Gavac (Heber Biotec S.A.) is able to control B. microplus populations in artificially infected grazing dairy cattle in Cuba. To assay the effect of the vaccine on a different B. microplus strain and under different ecological conditions, we conducted a trial in Brazil on grazing dairy and beef pure and cross-bred cattle under natural infestation conditions. A farm in the northeast of the state of Sao Paulo was selected and two groups of animals per breed were included in the experiment and were maintained grazing on separate but similar pastures. For each breed, one group was vaccinated with the vaccine Gavac and the second group was not vaccinated and was employed as a control. In vaccinated cattle, during 36 weeks of experiment, the average infestation rate was maintained below 78 ticks per animal while average infestation peaks (mean +/- S.E.) of 144 +/- 44 ticks per animal (for dairy cross-bred cattle) and 195 +/- 42 ticks per animal (for beef cross-bred cattle) were recorded in the control groups. Tick infestation rates showed statistical significant differences (p = 0.04) between both experimental groups throughout the experiment. These results clearly showed, as in the Cuban study, that the vaccine controlled tick numbers in successive generations in the field. PMID:8701597

  4. Análise de fatores genéticos e ambientais que afetam a infestação de fêmeas bovinas da raça Caracu por carrapatos (Boophilus microplus Genetic analysis of the infestation of Caracu female cattle breed by cattle tick (Boophilus microplus

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    Angelina Bossi Fraga

    2003-12-01

    Full Text Available Este trabalho foi conduzido com o objetivo de avaliar o efeito de fatores de meio sobre a infestação de bovinos Caracu pelo carrapato Boophilus microplus (Canestrini, 1887 e estimar parâmetros genéticos do grau de infestação por esse ectoparasita. Foram realizadas contagens em fêmeas de dois rebanhos, nas quatro estações, por dois anos consecutivos (setembro/1998 a julho/2000. Contou-se o número de carrapatos (NC em um dos lados do animal e atribuiu-se escore visual (EC de acordo com a quantidade de carrapatos no animal. Foram feitas de uma a oito avaliações, totalizando-se 4.079 e 3.994 observações de NC e EC, respectivamente, em 718 animais. Os dados foram analisados pelo método dos quadrados mínimos com um modelo que incluiu efeitos de rebanho (R, cor do animal (C, R x C, animal dentro de R x C como erro a, ano e estação da avaliação, espessura de pelame e idade do animal como covariável. As estimativas dos componentes de variância foram obtidas pelo método da máxima verossimilhança restrita livre de derivadas, utilizando-se um modelo que incluiu os efeitos fixos de grupo de contemporâneos (fazenda-ano-época, espessura do pelame e idade do animal como covariável e os efeitos aleatórios aditivos diretos e de ambiente permanente. Antes das análises, a variável NC foi transformada para log10 (n + 1 e EC para (x + 0,5½, em que n é o número de carrapatos contados no animal e x, o escore (0 a 4. A incidência de carrapatos foi maior no verão e, quanto maior a espessura do pelame, maior o nível de infestação. As estimativas de herdabilidade e repetibilidade foram, respectivamente, 0,22 e 0,29 para NC e 0,15 e 0,21 para EC; a correlação genética entre NC e EC foi igual a 1,00. Os resultados sugerem que é possível obter progresso genético para resistência a carrapato pela seleção.The objective of this study was to evaluate environmental aspects that affect the infestation of the Caracu cattle breed by the

  5. Caracterização do controle de Haematobia irritans e Rhipicephalus (Boophilus microplus no Triângulo Mineiro e Alto Paranaíba, Minas Gerais Characterization of Haematobia irritans and Rhipicephalus (Boophilus microplus control in Triângulo Mineiro and Alto Paranaíba, Minas Gerais

    Directory of Open Access Journals (Sweden)

    Luísa N. Domingues

    2012-12-01

    Full Text Available O controle eficaz de Haematobia irritans (mosca-dos-chifres e Rhipicephalus (Boophilus microplus (carrapato-do-boi é um fator crucial à maior rentabilidade da pecuária brasileira, porém ainda constitui-se um desafio. Um maior conhecimento das práticas adotadas no combate destes parasitos faz-se necessário para que se possam estruturar estratégias de controle mais próximas da realidade do produtor rural e mais fáceis de serem executadas. Este estudo caracterizou, através de entrevistas, as práticas adotadas no controle desses ectoparasitos em 23 propriedades da mesorregião do Triângulo Mineiro e Alto Paranaíba, Minas Gerais. A maioria dos entrevistados reconheceu a importância desses parasitos para a atividade pecuária, entretanto, diversos problemas relativos ao controle parasitário foram observados. O controle da mosca-dos-chifres e do carrapato-do-boi era uma prática rotineira em, respectivamente, 17,4% e 95,7% das propriedades, geralmente realizado em função de elevado grau de infestação dos animais. Mais de seis aplicações de ectoparasiticidas eram realizadas por ano em todas as propriedades que empregavam tratamentos para o controle da mosca e em 76,5% daquelas que combatiam o carrapato. Os produtos eram aplicados principalmente com bombas costais manuais (63,6% e sem a contenção dos animais em 45,5% das propriedades. A diluição dos produtos segundo recomendações dos fabricantes era realizada por 45,4% dos entrevistados, porém, 63,6% aplicavam um volume de solução por animal menor do que o tecnicamente recomendado. Utilizava-se principalmente a associação de piretróides e organofosforados para o controle de ambos os parasitos. Apesar de utilizar rotineiramente ectoparasiticidas, o uso de equipamento de proteção individual (EPI não era comum entre os entrevistados. A maioria dos entrevistados conhecia algumas características epidemiológicas dos parasitos, entretanto, o controle parasitário adotado na

  6. In vitro activity of 3β-O-tigloylmelianol from Guarea kunthiana A. Juss (Meliaceae) on oogenesis and ecdysis of the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae).

    Science.gov (United States)

    Barbosa, Carolina da Silva; Borges, Lígia Miranda Ferreira; Louly, Carla Cristina Braz; Rocha, Thiago Lopes; de Sabóia-Morais, Simone Maria Teixeira; Miguita, Carlos Henrique; Garcez, Walmir Silva; Garcez, Fernanda Rodriguez

    2016-05-01

    We evaluated the effects of 3β-O-tigloylmelianol from Guarea kunthiana A. Juss (Meliaceae) on oogenesis, as a larvicide and on ecdysis of the larvae and the nymphs of the cattle tick Rhipicephalus (Boophilus) microplus (Canestrini) (Acari: Ixodidae). On the oogenesis' test, 48 engorged females were divided into three groups, evaluated at 24, 48 and 72 h post-treatment. Half of the females were treated with 0.01% 3β-O-tigloylmelianol diluted in distilled water and 5% dimethyl sulfoxide (DMSO), while the other half (controls) were exposed to distilled water and 5% DMSO. After treatment, the ovaries were weighed in order to measure the gonadosomatic index (GSI) and were also subjected to standard histological technical tests. On the larvicide and ecdysis' tests, 3β-O-tigloylmelianol was tested at concentrations of 0.01, 0.005, 0.0025 and 0.00125%. Compared with the controls, there was a reduction of GSI of approximately 50% on the treated group, which started at 48 h post treatment. Overall, the protolimonoid 3β-O-tigloylmelianol has caused a significant reduction in the number of oocytes. It has also caused alteration of the cytoplasmic and germinal vesicle diameters. Morphological changes, such as vacuolization, chorion irregularity which has modified the oocytes' morphology as well as alterations on the yolk's granules were also observed. The compound was not larvicide, however, interfered in the ecdysis of the larvae and the nymphs. This study shows that the protolimonoid 3β-O-tigloylmelianol from G. kunthiana acts on oogenesis and ecdysis of R. (B.) microplus, but not as larvicide, indicating that it acts on the endocrine system of the tick.

  7. Molecular and pharmacological characterization of the first Chelicerata pyrokinin receptor from a worldwide tick vector of zoonotic pathogens, Rhipicephalus (Boophilus) microplus

    Science.gov (United States)

    We identified the first pyrokinin receptor (Rhimi-PK-R) from the Chelicerata and analyzed structure-activity relationships of cognate ligand neuropeptides and their analogs. This receptor, which we cloned from larvae of the tick Rhipicephalus microplus (Acari: Ixodidae), is the ortholog of the inse...

  8. 3β-O-Tigloylmelianol from Guarea kunthiana: A New Potential Agent to Control Rhipicephalus (Boophilus) microplus, a Cattle Tick of Veterinary Significance

    OpenAIRE

    Carlos Henrique Miguita; Carolina da Silva Barbosa; Lidilhone Hamerski; Ulana Chaves Sarmento; José Nicácio do Nascimento; Walmir Silva Garcez; Fernanda Rodrigues Garcez

    2014-01-01

    Chemical investigation of Guarea kunthiana fruits, guided by their effect on the reproductive cycle of engorged females of the cattle tick Rhipicephalus (Boophilus) microplus—a major economic problem to the livestock industry worldwide—led to isolation of 3β-O-tigloylmelianol, a new protolimonoid, from the bioactive hexane phase obtained by partitioning the crude ethanol extract. An adult immersion test was performed. The compound strongly inhibited egg-laying and hatchability (99.2% effect...

  9. Detección de resistencia a los acaricidas en la garrapata del ganado Boophilus microplus mediante análisis de zimogramas

    OpenAIRE

    Estefan Miranda Miranda; Jorge Miranda Osorio; Raquel Cossío Bayúgar

    2005-01-01

    La identificación de resistencia a los productos acaricidas en la garrapata B. microplus, se hace mediante un complicado bioensayo, que requiere garrapatas de referencia y de campo cultivadas sobre bovinos vivos y restringidos durante semanas. Con el fin de evaluar una posible alternativa diagnóstica, se hicieron ensayos enzimáticos en geles de poliacrilamida- SDS, usando extractos de larvas de garrapatas provenientes de cuatro cepas de referencia con diferentes niveles de resistencia y susce...

  10. [Molecular analysis of the antigenic sequence (SBm7462®) from Bm86 of the Rhipicephalus (Boophilus) microplus and similarity with Rhipicephalus sanguineus and Hyalomma anatolicum anatolicum].

    Science.gov (United States)

    Peconick, Ana P; Sossai, Sidimar; Medeiros, Carla L; Carvalho, Gabriel D; Vargas, Marlene I; Patarroyo, Joaquín H

    2008-09-01

    The vaccination represents optimum method evaluated with effective cost to prevent economic losses and to increase the duration and quality of life of the production animals. . Diverse vaccines are produced from the intestinal protein Bm86 of the Rhipicephalus. (B.) microplus. The knowledge of the conservation of the gene bm86 is very important to evaluate the vaccine efficiency and the possibility of reaction crossed between different species of ticks. Samples of R. (B.) microplus come from different localities had been sequenced. The analyses of multiple alignments of the sequences had been made through the BioEdit program 7.0.5.3 version and the verification of polymorphism for visual inspection. In this work the alignment of all was become fulfilled sequences using itself BLAST in the search for similarity. Similarity was observed enters the sequenced fragments of R. (B.) microplus with the sequence of the protein Rs86 de Rhipicephalus sanguineus and with protein HA98 of the tick Hyalomma anatolicum anatolicum. The results give molecular support to synthetic the vaccine use based in the gene bm86 (SBm7462®) to be used in different species of ticks. PMID:20059809

  11. Acaricidal properties of vetiver essential oil from Chrysopogon zizanioides (Poaceae) against the tick species Amblyomma cajennense and Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

    Science.gov (United States)

    Campos, Roseane Nunes de Santana; Nascimento Lima, Cecília Beatriz; Passos Oliveira, Alexandre; Albano Araújo, Ana Paula; Fitzgerald Blank, Arie; Barreto Alves, Péricles; Nascimento Lima, Rafaely; Albano Araújo, Vinícius; Santana, Alisson Silva; Bacci, Leandro

    2015-09-15

    Ticks are arthropods widely distributed in tropical and subtropical regions, which can transmit infectious agents also responsible for zoonoses. Excessive use of conventional acaricides has resulted in the onset of drug resistance by these parasites, thus the need to use alternative methods for their control. This study evaluated the acaricidal activities of Chrysopogon zizanioides (vetiver) essential oils containing different zizanoic and khuzimol (high and low acidity) acid concentrations on Amblyomma cajennense and Rhipicephalus microplus (Acari: Ixodidae). To this aims, toxicity tests of different concentrations of examined essential oils were conducted on adult females and larval stages. Results showed that the essential oils of C. zizanioides with high and low acidity reduced oviposition of females, eggs hatch and larval survival, being more effective than some commercial products widely used to control these ectoparasites. These results indicate that the C. zizanoides essential oils are promising candidates as acaricidal agents and represent also an add value to vetiver oil with high acidity, which is commercially undervalued in the cosmetic industry. PMID:26359641

  12. A Mitochondrial Membrane Exopolyphosphatase Is Modulated by, and Plays a Role in, the Energy Metabolism of Hard Tick Rhipicephalus (Boophilus microplus Embryos

    Directory of Open Access Journals (Sweden)

    Carlos Logullo

    2011-06-01

    Full Text Available The physiological roles of polyphosphates (polyP recently found in arthropod mitochondria remain obscure. Here, the relationship between the mitochondrial membrane exopolyphosphatase (PPX and the energy metabolism of hard tick Rhipicephalus microplus embryos are investigated. Mitochondrial respiration was activated by adenosine diphosphate using polyP as the only source of inorganic phosphate (Pi and this activation was much greater using polyP3 than polyP15. After mitochondrial subfractionation, most of the PPX activity was recovered in the membrane fraction and its kinetic analysis revealed that the affinity for polyP3 was 10 times stronger than that for polyP15. Membrane PPX activity was also increased in the presence of the respiratory substrate pyruvic acid and after addition of the protonophore carbonyl cyanide-p-trifluoromethoxyphenylhydrazone. Furthermore, these stimulatory effects disappeared upon addition of the cytochrome oxidase inhibitor potassium cyanide and the activity was completely inhibited by 20 µg/mL heparin. The activity was either increased or decreased by 50% upon addition of dithiothreitol or hydrogen peroxide, respectively, suggesting redox regulation. These results indicate a PPX activity that is regulated during mitochondrial respiration and that plays a role in adenosine-5’-triphosphate synthesis in hard tick embryos.

  13. Acaricidal properties of vetiver essential oil from Chrysopogon zizanioides (Poaceae) against the tick species Amblyomma cajennense and Rhipicephalus (Boophilus) microplus (Acari: Ixodidae).

    Science.gov (United States)

    Campos, Roseane Nunes de Santana; Nascimento Lima, Cecília Beatriz; Passos Oliveira, Alexandre; Albano Araújo, Ana Paula; Fitzgerald Blank, Arie; Barreto Alves, Péricles; Nascimento Lima, Rafaely; Albano Araújo, Vinícius; Santana, Alisson Silva; Bacci, Leandro

    2015-09-15

    Ticks are arthropods widely distributed in tropical and subtropical regions, which can transmit infectious agents also responsible for zoonoses. Excessive use of conventional acaricides has resulted in the onset of drug resistance by these parasites, thus the need to use alternative methods for their control. This study evaluated the acaricidal activities of Chrysopogon zizanioides (vetiver) essential oils containing different zizanoic and khuzimol (high and low acidity) acid concentrations on Amblyomma cajennense and Rhipicephalus microplus (Acari: Ixodidae). To this aims, toxicity tests of different concentrations of examined essential oils were conducted on adult females and larval stages. Results showed that the essential oils of C. zizanioides with high and low acidity reduced oviposition of females, eggs hatch and larval survival, being more effective than some commercial products widely used to control these ectoparasites. These results indicate that the C. zizanoides essential oils are promising candidates as acaricidal agents and represent also an add value to vetiver oil with high acidity, which is commercially undervalued in the cosmetic industry.

  14. Molecular analysis of Boophilus spp. (Acari: Ixodidae) tick strains.

    Science.gov (United States)

    Fuente, J; García-García, J C; González, D M; Izquierdo, G; Ochagavia, M E

    2000-10-01

    Boophilus spp. (Acari: Ixodidae) parasitize cattle and other farm and wild animals in tropical and subtropical regions of the world. Ticks belonging to the genus Boophilus have undergone evolutionary processes associated with habitat adaptation following biogeographical separation, resulting in strains with marked morphological differences. We have characterized at the molecular level B. microplus strains from Latin America and Australia, employing sequences derived from the bm86 coding region, an intron located within the bm86 gene, and DNA short tandem repeats (STR). A B. annulatus strain was employed for comparison. The results indicated that variation within the bm86 coding region is higher between B. microplus strains than between some B. microplus strains and B. annulatus. The sequence of the intron was not informative for phylogenetic analysis, varying among individuals of the same strain. Two STRs were identified in B. microplus (STRs BmM1 and BmM2) and one in B. annulatus (STR Ba1). Southern hybridization experiments with STRs BmM1 and BmM2 as a probe revealed the prevalence of dispersed moderately repeated DNA in the genome of B. microplus. The analysis of polymorphism at STR locus BmM1 evidenced differences within and between populations of B. microplus. These results support at the molecular level the existing differences between B. microplus strains and suggest tools to characterize these populations. PMID:10962158

  15. VIABILIDADE ECONÔMICA DA ADOÇÃO DO CONTROLE ESTRATÉGICO DO CARRAPATO RHIPICEPHALUS (BOOPHILUS MICROPLUS (CANESTRINI, 1887 EM REBANHOS BOVINOS LEITEIROS

    Directory of Open Access Journals (Sweden)

    André Monteiro de Souza

    2014-06-01

    acaricidas. Com isso, 90% notaram a diminuição dos ataques pelo parasito, mudando a maneira de realizar os banhos (100% dos produtores. Houve a redução de 57% dos gastos em reais com a compra de carrapaticidas por mês e de 33% da quantidade de tratamentos por ano. Em relação à TPB, houve queda de 60% do número médio de casos e 100% da média do número de mortes em bezerros. Portanto, os resultados indicaram que a adoção do controle estratégico do carrapato em bovinos leiteiros possibilitou a redução das despesas dos produtores com aquisição de carrapaticidas químicos. Além disso, a adoção do controle estratégico possibilitou a redução de prejuízos diretos e indiretos causados pelo carrapato, com reflexos positivos sobre a produção e a qualidade do leite e derivados.

  16. Comparison of predicted binders in Rhipicephalus (Boophilus microplus intestine protein variants BM86 Campo Grande strain, BM86 and BM95 Comparação da previsão de ligação das variantes de proteína de intestino de Rhipicephalus (Boophilus microplus Bm86 cepa Campo Grande, Bm86 e Bm95

    Directory of Open Access Journals (Sweden)

    Renato Andreotti

    2008-06-01

    Full Text Available This paper reports the sequence analysis of Bm86 Campo Grande strain comparing it with Bm86 and Bm95 antigens from the preparations TickGardPLUS and GavacTM, respectively. The PCR product was cloned into pMOSBlue and sequenced. The secondary structure prediction tool PSIPRED was used to calculate alpha helices and beta strand contents of the predicted polypeptide. The hydrophobicity profile was calculated using the algorithms from the Hopp and Woods method, in addition to identification of potential MHC class-I binding regions in the antigens. Pair-wise alignment revealed that the similarity between Bm86 Campo Grande strain and Bm86 is 0.2% higher than that between Bm86 Campo Grande strain and Bm95 antigens. The identities were 96.5% and 96.3% respectively. Major suggestive differences in hydrophobicity were predicted among the sequences in two specific regions.O objetivo deste estudo foi analisar a seqüência de Bm86 cepa Campo Grande comparando-a com os antígenos Bm86 e Bm95 das preparações TickGardPLUS e GavacTM, respectivamente. O produto de PCR foi clonado em PMOSBlue e seqüenciado. Para calcular os conteúdos de alfa-hélice e fita beta do polipeptídio previsto, foi utilizada a ferramenta de prognóstico de estrutura secundária PSIPRED. O perfil de hidrofobicidade foi calculado usando os algoritmos de Hopp e Woods, além da identificação das possíveis regiões de ligação com MHC classe I nos antígenos. O alinhamento "pair-wise" revelou que a similaridade entre Bm86 cepa Campo Grande e Bm86 é 0,2% maior que aquela entre Bm86 cepa Campo Grande e Bm95. As identidades foram de 96,5% e 96,3%, respectivamente. Com relação à hidrofobicidade, os resultados sugerem que a maior diferença entre as seqüências está localizada em duas regiões específicas.

  17. Immunological Profiles of Bos taurus and Bos indicus Cattle Infested with the Cattle Tick, Rhipicephalus (Boophilus) microplus▿ †

    OpenAIRE

    Piper, Emily K.; Jonsson, Nicholas N.; Gondro, Cedric; Lew-Tabor, Ala E.; Moolhuijzen, Paula; Vance, Megan E.; Jackson, Louise A.

    2009-01-01

    The cattle tick, Rhipicephalus (Boophilus) microplus, is a major threat to the improvement of cattle production in tropical and subtropical countries worldwide. Bos indicus cattle are naturally more resistant to infestation with the cattle tick than are Bos taurus breeds, although considerable variation in resistance occurs within and between breeds. It is not known which genes contribute to the resistant phenotype, nor have immune parameters involved in resistance to R. microplus been fully ...

  18. Rhipicephalus microplus strain Deutsch, whole genome shotgun sequencing project Version 2

    Science.gov (United States)

    The cattle tick, Rhipicephalus (Boophilus) microplus, has a genome over 2.4 times the size of the human genome, and with over 70% of repetitive DNA, this genome would prove very costly to sequence at today's prices and difficult to assemble and analyze. Cot filtration/selection techniques were used ...

  19. Reduced efficacy of commercial acaricides against populations of resistant cattle tick Rhipicephalus microplus from two municipalities of Antioquia, Colombia

    Science.gov (United States)

    Two distant Antioquian cattle farms where systemic and topical acaricides had previously failed to control infestations by Rhipicephalus (Boophilus) microplus were studied. An initial in vivo study was conducted using single subcutaneous injections with a long-acting formulation of ivermectin (630 µ...

  20. Prediction of G protein-coupled receptor encoding sequences from the synganglion transcriptome of the cattle tick, Rhipicephalus microplus

    Science.gov (United States)

    The cattle tick, Rhipicephalus (Boophilus) microplus, is a pest which causes multiple health complications in cattle. The G-protein coupled receptor (GPCR) super-family presents an interesting target for developing novel tick control methods. However, GPCRs share limited sequence similarity among or...

  1. Comparison of efficiency and reproductive aptitude indexes between a reference and field strains of the cattle tick Rhipicephalus (Boophilus microplus, in Sinaloa, Mexico Comparação dos índices de eficiência e aptidão reprodutiva entre uma cepa de referência e outra de campo do carrapato do gado, Rhipicephalus (Boophilus microplus, em Sinaloa, México

    Directory of Open Access Journals (Sweden)

    Soila Gaxiola-Camacho

    2009-12-01

    Full Text Available The objective of this work was to study the reproductive behavior of two strains of R. (B. microplus, one wild-caught (Native and one reference strain (Media Joya for two years, measuring the reproductive efficiency index (REI and reproductive aptitude index (RAI. Engorged ticks from each strain were collected monthly from February 2002 to February 2004. These were weighed and kept in the laboratory until egg-laying. Oogenic masses were individually weighed and incubated until larvae emergence. REI and RAI were calculated from each sample, grouping ticks by weight in 100 mg range classes. An analysis of variance and Duncan's multiple rank tests were carried out on the data (P O objetivo deste trabalho foi estudar a conduta reprodutiva de duas cepas de R. (B. microplus, uma coletada no campo (Nativa e outra de referência (Média Jóia, por dois anos, calculando o índice de eficiência reprodutiva (REI e o índice de aptidão reprodutiva (RAI. Foram coletados mensalmente carrapatos fêmeas engurgitadas de cada cepa no período de Fevereiro de 2002 a Fevereiro de 2004. Estas foram pesadas e conservadas no laboratório até ovipositar. As massas de ovos foram pesadas individualmente e incubadas até a eclosão das larvas. O REI e o RAI foram calculados para cada coleta, agrupando os carrapatos em classe de peso de 100 mg. Os dados foram submetidos a uma análise de variância e prova de classe múltipla de Duncan (P < 0,05. Foram calculados os coeficientes de correlação de Pearson (P < 0,01 para estimar a associação entre o peso dos carrapatos engurgitados e o peso e número de ovos postos e eclosionados. A cepa Nativa mostrou um peso ao engurgitamento mais alto do que a cepa Média Jóia. Os valores de REI e de RAI em ambas cepas foram similares em todos as classes de peso, mostrando tendência cuadrática na Média Jóia e linear-cuadrática na cepa Nativa (P < 0,05. Ambos os índices por classe de peso no engurgitamento foram sempre mais

  2. 9 CFR 72.1 - Ticks [Boophilus annulatus (Margaropus annulatus), Boophilus microplus, or Rhipicephalus evertsi...

    Science.gov (United States)

    2010-01-01

    ... POULTRY) AND ANIMAL PRODUCTS TEXAS (SPLENETIC) FEVER IN CATTLE § 72.1 Ticks ; interstate movement of... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Ticks ; interstate movement of infested or exposed animals prohibited. 72.1 Section 72.1 Animals and Animal Products ANIMAL AND...

  3. Lesser protein degradation machinery correlates with higher BM86 tick vaccine efficacy in Rhipicephalus annulatus when compared to Rhipicephalus microplus.

    Science.gov (United States)

    Popara, Marina; Villar, Margarita; Mateos-Hernández, Lourdes; de Mera, Isabel G Fernández; Marina, Anabel; del Valle, Mercedes; Almazán, Consuelo; Domingos, Ana; de la Fuente, José

    2013-10-01

    Infestations with cattle ticks, Rhipicephalus (Boophilus) microplus and Rhipicephalus annulatus, economically impact cattle production in tropical and subtropical regions of the world. Vaccines containing the recombinant R. microplus BM86 gut antigen were developed and commercialized to induce an immunological protection in cattle against tick infestations. These vaccines demonstrated that tick control by vaccination is cost-effective, reduces environmental contamination and prevents the selection of drug resistant ticks that result from repeated acaricide applications. The protection elicited by BM86-containing vaccines against tick infestations is mediated by a collaborative action between the complement system and IgG antibodies. The efficacy of the vaccination with BM86 and other tick antigens is always higher for R. annulatus than against R. microplus, suggesting that tick genetic and/or physiological factors may affect tick vaccine efficacy. These factors may be related to BM86 protein levels or tick physiological processes such as feeding and protein degradation that could result in more efficient antibody-antigen interactions and vaccine efficacy. To test this hypothesis, we compared the proteome in R. annulatus and R. microplus female ticks after feeding on BM86-vaccinated and control cattle. The results showed that cattle proteins were under represented in R. annulatus when compared to R. microplus, suggesting that R. annulatus ticks ingested less blood, a difference that increased when feeding on vaccinated cattle, probably reflecting the effect of antibody-BM86 interactions on this process. The results also showed that tick protein degradation machinery was under represented in R. annulatus when compared to R. microplus. BM86 mRNA and protein levels were similar in both tick species, suggesting that lesser protease activity in R. annulatus results in more efficient antibody-antigen interactions and higher vaccine efficacy. These results have important

  4. Histoarchitecture of the Ovary of Rhipicephalus (Boophilus annulatus during Pre- and Postengorgement Period

    Directory of Open Access Journals (Sweden)

    Sreelekha Kanapadinchareveetil

    2015-01-01

    Full Text Available The present communication describes the detailed day wise study of histological changes of the ovary of Rhipicephalus (Boophilus annulatus in the postengorgement period together with the systematic classification of their oocytes. The ovary of R. (B. annulatus is panoistic type with an asynchronous development of oocytes. All the stages (II, III, IV, and V of oocytes except stage I were similar to R. (B. microplus. The stage I oocytes showed basophilia, which was not reported earlier in other species of ticks. Day wise changes were in the form of presence of oogonia in partially fed and day one engorged adults, considerable degeneration of oocytes on day two, emergence of new wave of oocytes on day three, presence of mature oocytes up to day eight, and complete degeneration of ovarian tissue from day eight onwards. The degenerative changes in the ovary appeared initially in the oocytes followed by germinal epithelium.

  5. Acaricidal properties of the essential oil from Zanthoxylum caribaeum against Rhipicephalus microplus.

    Science.gov (United States)

    Nogueira, Jeane; Vinturelle, Rafaelle; Mattos, Camila; Tietbohl, Luis Armando Candido; Santos, Marcelo Guerra; Junior, Itabajara Silva Vaz; Mourão, Samanta Cardozo; Rocha, Leandro; Folly, Evelize

    2014-09-01

    Zanthoxylum caribaeum Lamarck (Rutaceae) is plant species with a variety of medical applications, including insecticidal activity. This study determined the bioacaricidal activity of the essential oil from Z. caribaeum leaves against engorged Rhipicephalus (Boophilus) microplus (Canestrini, 1887) females using the adult immersion test. For this purpose, three serial concentrations (5.0, 2.5, and 1.25%, vol:vol, in 1% dimetilsulfoxide) of the essential oil were used. Essential oil 5% caused 65% mortality on the first day after treatment, 85% on the second day, and 100% mortality by the fifth day. To our knowledge, this is the first demonstration of the acaricidal activity of the essential oil from Z. caribaeum leaves against cattle ticks.

  6. Vaccination against ticks (Boophilus spp.): the experience with the Bm86-based vaccine Gavac.

    Science.gov (United States)

    de la Fuente, J; Rodríguez, M; Montero, C; Redondo, M; García-García, J C; Méndez, L; Serrano, E; Valdés, M; Enríquez, A; Canales, M; Ramos, E; Boué, O; Machado, H; Lleonart, R

    1999-11-01

    The control of tick infestations and the transmission of tick-borne diseases remain a challenge for the cattle industry in tropical and subtropical areas of the world. Traditional control methods have been only partially successful and the parasites continue to result in significant losses for the cattle industry. Recently, vaccines containing the recombinant B. microplus gut antigen Bm86 have been developed. Our vaccine formulation (Gavac, Heber Biotec S.A., Havana, Cuba) has been registered and is commercially available in Cuba, Colombia, Dominican Republic, Brazil and Mexico. In controlled pen trials, Gavac has been effective for the control of artificial infestations of B. annulatus, B. decoloratus and chemical-sensitive and resistant B. microplus strains from Australia, Africa, America and Iran. In controlled field trials in Cuba, Brazil, Argentina and Mexico, Gavac has shown a 55-100% efficacy in the control of B. microplus infestations in grazing cattle 12-36 weeks after the first vaccination. Field trials under production conditions have been conducted in Cuba, Colombia, Brazil and Mexico in pure and cross-bred cattle herds. The application of Gavac has increased the time between acaricide treatments by an average of 32 /-21 days (P = 0.0005) resulting in important savings for the cattle industry. In Cuba, a cost-effectiveness analysis was conducted in more than 260000 animals. The cost-effectiveness analysis showed a 60% reduction in the number of acaricide treatments, together with the control of tick infestations and transmission of babesiosis, which resulted in savings of 23.4 dollars animal(-1) year (-1). These results clearly demonstrate the advantage of vaccination and support the application of Gavac for the control of Boophilus spp. infestations. PMID:10596754

  7. Acaricidal activity of synthesized titanium dioxide nanoparticles using Calotropis gigantea against Rhipicephalus microplus and Haemaphysalis bispinosa

    Institute of Scientific and Technical Information of China (English)

    Sampath Marimuthu; Moorthy Iyappan; Chinnadurai Siva; Loganathan Karthik; Kokati Venkata Bhaskara Rao; Abdul Abdul Rahuman; Chidambaram Jayaseelan; Arivarasan Vishnu Kirthi; Thirunavukkarasu Santhoshkumar; Kanayairam Velayutham; Asokan Bagavan; Chinnaperumal Kamaraj; Gandhi Elango

    2013-01-01

    Objective: To assess the acaricidal activity of titanium dioxide nanoparticles (TiO2 NPs) synthesized from flower aqueous extract of Calotropis gigantea (C. gigantea) against the larvae of Rhipicephalus (Boophilus) microplus [R. (B.) microplus] and the adult of Haemaphysalis bispinosa (H. bispinosa). Methods: The lyophilized C. gigantea flower aqueous extract of 50 mg was added with 100 mL of TiO(OH)2 (10 mM) and magnetically stirred for 6 h. Synthesized TiO2 NPs were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Energy dispersive X-ray spectroscopy (EDX). The synthesised TiO2 NPs were tested against the larvae of R. (B.) microplus and adult of H. bispinosa were exposed to filter paper impregnated method. Results:XRD confirmed the crystalline nature of the nanoparticles with the mean size of 10.52 nm. The functional groups for synthesized TiO2 NPs were 1 405.19, and 1 053.45 cm-1 for-NH2 bending, primary amines and amides and 1 053.84 and 1 078.45 cm-1 for C-O. SEM micrographs of the synthesized TiO2 NPs showed the aggregated and spherical in shape. The maximum efficacy was observed in the aqueous flower extract of C. gigantea and synthesized TiO2 NPs against R. (B.) microplus (LC50=24.63 and 5.43 mg/L and r2=0.960 and 0.988) and against H. bispinosa (LC50=35.22 and 9.15 mg/L and r2=0.969 and 0.969), respectively. Conclusions: The synthesized TiO2 NPs were highly stable and had significant acaricidal activity against the larvae of R. (B.) microplus and adult of H. bispinosa. This study provides the first report of synthesized TiO2 NPs and possessed excellent anti-parasitic activity.

  8. Vaccination of cattle with TickGARD induces cross-reactive antibodies binding to conserved linear peptides of Bm86 homologues in Boophilus decoloratus.

    Science.gov (United States)

    Odongo, David; Kamau, Lucy; Skilton, Robert; Mwaura, Stephen; Nitsch, Cordula; Musoke, Anthony; Taracha, Evans; Daubenberger, Claudia; Bishop, Richard

    2007-01-26

    Vaccines based on recombinant Bm86 gut antigen from Boophilus microplus are a useful component of integrated control strategies against B. microplus infestations of cattle. The capacity of such vaccines to control heterologous infestations by two African tick species was investigated. The mean weight of engorged female ticks and mean egg mass per tick were significantly reduced in B. decoloratus infestations, but there was no effect of the vaccine against adult Rhipicephalus appendiculatus. We cloned, sequenced and expressed two Bm86 homologues (Bd86) from B. decoloratus. Amino acid sequence identity between Bd86 homologues (Bd86-1 and Bd86-2) and Bm86 was 86% and 85%, respectively, compared to 93% identity between the variants. Native Bd86 protein in B. decoloratus tick mid-gut sections and recombinant Bd86-1 reacted strongly with sera from TickGARD vaccinated cattle. TickGARD can therefore protect against a heterologous tick species with multiple antigen sequences. Epitope mapping using sera from TickGARD-vaccinated cattle identified two linear peptides conserved between the Bd86 homologues and Bm86. These epitopes represent candidate synthetic peptide vaccines for control of Boophilus spp. and the pathogens transmitted by these tick vectors. PMID:17070625

  9. Survey of cattle tick, Riphicephalus (Boophilus) microplus, resistance to amitraz and deltamethrin in New Caledonia.

    Science.gov (United States)

    Petermann, J; Cauquil, L; Hurlin, J C; Gaia, H; Hüe, T

    2016-02-15

    The evolution of tick resistance to acaricides in New Caledonia was followed in two ways: through two large scale surveys in 1998 and 2014 and through the routine analysis of samples of ticks with suspected resistance. The results of the two approaches were qualitatively similar though analysis of ticks with suspected resistance gave higher frequencies of resistance, as expected of a biased sample. Resistance tests using a larval packet test have been conducted since 1993 for deltamethrin and 2003 for amitraz. Deltamethrin was used in country-wide control from 1986 to 2003 and amitraz since 1996. This study analyzed the variation of resistance parameters such as lethal concentration 50 (LC50) and the resistance factor over 21 years for deltamethrin and LC99 over 11 years for amitraz. There was an increase in deltamethrin's annual mean LC50 from 1993 to 2004 when it reached 2.9 g/l and then a progressive decrease, reaching a level consistently below 1g/l since 2007. Even though breeders stopped using deltamethrin in New Caledonia in 2003, the percentage of susceptible strains has remained below 30% since 1998. Amitraz's LC99 mean increased significantly from 0.31 g/l in 2003 to 2.96 g/l in 2014. Whereas all tested strains in 2003 were susceptible, only 40% of strains tested at the request of farmers were susceptible in 2014. The recent territory-wide survey showed that 76.7% of strains are still susceptible. This study established that resistance to amitraz has developed slowly in New Caledonia. A reversion phenomenon may have occurred concerning deltamethrin resistance, visible through the decrease of LC50 mean and the decreased proportion of very resistant strains; however the proportion of susceptible strains remains at a low level and there is anecdotal evidence that high resistance can re-emerge rapidly. PMID:26827863

  10. Nuclear glycogen synthase kinase-3 {beta} (GSK-3) in Rhipicephalus (Boophilus) microplus tick embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Mentzingen, Leticia; Andrade, Josiana G. de; Logullo, Carlos [Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, RJ (Brazil). Centro de Biociencias e Biotecnologia. Lab. de Quimica e Funcao de Proteinas e Peptideos (LQFPP); Andrade, Caroline P. de; Vaz Junior, Itabajara [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Centro de Biotecnologia

    2008-07-01

    Full text: Glycogen synthase kinase-3 (GSK3) is recognized as a key component of a large number of cellular processes and diseases. Several mechanisms play a part in controlling the actions of GSK3, including phosphorylation, protein complex formation, and subcellular distribution. Recent observations point to functions for phosphorylases several transcription factors in the nucleus. Also, GSK3b participate of the canonical W nt signalling pathway, which has been studied intensively in embryonic and cancer cells. Like in many other signaling pathways, most components in W nt signal transduction were highly conserved during the evolution. More than 40 proteins have been reported to be phosphorylated by GSK3, including over a dozen transcription factors. Although the mechanisms regulating GSK3 are not fully understood, precise control appears to be achieved by a combination of phosphorylation, localization, and interactions with GSK3-binding proteins. Although GSK3 is traditionally considered a cytosolic protein, it is also present in nuclei. Nuclear GSK3 is particularly interesting because of the many transcription factors that it regulates enabling GSK3 to influence many signaling pathways that converge on these transcription factors, thereby regulating the expression of many genes. Our group identified that GSK-3 {beta} could be detected in different stage eggs of R. micro plus. In this work we detected the GSK-3 in isolated nuclear fraction from the egg homogenates of R. micro plus by western-blot analysis, using anti-GSK- 3 {beta} antibodies. The enzyme activity was also detected radiochemically throughout embryogenesis in same fraction. The GSK-3 activity was inhibiting by using SB 216763 (selective molecule inhibitors of GSK-3). Taken together our results suggest that GSK-3 {beta} isoform probably is involved in gene transcription factors during R. micro plus embryo development.

  11. Acaricidal properties of Ricinus communis leaf extracts against organophosphate and pyrethroids resistant Rhipicephalus (Boophilus) microplus.

    Science.gov (United States)

    Ghosh, Srikanta; Tiwari, Shashi Shankar; Srivastava, Sharad; Sharma, Anil Kumar; Kumar, Sachin; Ray, D D; Rawat, A K S

    2013-02-18

    Indian cattle ticks have developed resistance to commonly used acaricides and an attempt has been made to formulate an ecofriendly herbal preparation for the control of acaricide resistant ticks. A 95% ethanolic extract of Ricinus communis was used to test the efficacy against reference acaricide resistant lines by in vitro assay. In in vitro assay, the extract significantly affects the mortality rate of ticks in dose-dependent manner ranging from 35.0 ± 5.0 to 95.0 ± 5.0% with an additional effect on reproductive physiology of ticks by inhibiting 36.4-63.1% of oviposition. The leaf extract was found effective in killing 48.0, 56.7 and 60.0% diazinon, deltamethrin and multi-acaricide resistant ticks, respectively. However, the cidal and oviposition limiting properties of the extract were separated when the extract was fractionated with hexane, chloroform, n-butanol and water. The HPTLC finger printing profile of R. communis leaf extract under λ(max.) - 254 showed presence of quercetin, gallic acid, flavone and kaempferol which seemed to have synergistic acaricidal action. In vivo experiment resulted in 59.9% efficacy on Ist challenge, however, following 2nd challenge the efficacy was reduced to 48.5%. The results indicated that the 95% ethanolic leaf extract of R. communis can be used effectively in integrated format for the control of acaricide resistant ticks.

  12. Reproductive and safety assessment of vaccination with Gavac against the cattle tick (Boophilus microplus).

    Science.gov (United States)

    Boué, O; Redondo, M; Montero, C; Rodríguez, M; de la Fuente, J

    1999-06-01

    Recent developments in cattle tick control have incorporated the use of recombinant Bm86 vaccines against this ectoparasite. The vaccine developed by our group (Gavac) contains an antigen expressed in Pichia pastoris, and has been successfully employed for the control of tick infestations and transmission of tick-borne diseases. Here, we examined the safety and effect of the Gavac vaccine on reproductive parameters in cattle. Toxicity tests in mice and guinea pigs demonstrated the safety of Gavac. To study the adverse effects of vaccination on reproduction, a field trial involving 9,500 animals in Cuba was conducted. The cattle at 3 farms were vaccinated while those on a fourth farm were left unvaccinated and served as the control. Following vaccination, the control of tick infestation and the transmission of babesiosis were used to demonstrate the efficacy of the vaccine. No adverse effects were observed in any of the reproductive parameters studied when comparing the data before and after vaccination with Gavac and between the vaccinated farms and the control farm. These results demonstrate that under the conditions of our study vaccination with Gavac is safe for use on cattle. PMID:10729081

  13. Cloning and expression of a protective antigen from the cattle tick Boophilus microplus.

    OpenAIRE

    Rand, K N; Moore, T.; Sriskantha, A; Spring, K; Tellam, R; P. Willadsen; Cobon, G S

    1989-01-01

    Glycoproteins located on the luminal surface of the plasma membrane of tick gut epithelial cells, when used to vaccinate cattle, are capable of stimulating an immune response that protects cattle against subsequent tick infestation. One such tick gut glycoprotein, designated Bm86, has been purified to homogeneity and the amino acid sequences of peptide fragments generated by endoproteinase Lys-C digestion have been determined. We report here the isolation and characterization of a cDNA that e...

  14. Phosphoenolpyruvate carboxykinase in bovine tick Rhipicephalus (Boophilus) micro plus embryogenesis and starvation larvae

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, J.G. de; Mentizingen, L.G.; Logullo, C. [Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, RJ (Brazil). Centro de Biociencias e Biotecnologia. Lab.de Quimica e Funcao de Proteinas e Peptideos (LQFPP); Andrade, C.P. de; Vaz Junior, Itabajara [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Centro de Biotecnologia; Daffre, S.; Esteves, E. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Ciencias Biomedicas

    2008-07-01

    Full text: Phosphoenolpyruvate carboxykinase (PEPCK) is considered a key rate controlling enzyme in gluconeogenesis pathway. Gluconeogenesis is a highly regulated process, catalyzed by several enzymes subject to regulation by insulin. Normally, insulin rapidly and substantially inhibits PEPCK gene transcription and the PEPCK activity is proportional to the rate of gene transcription. The transcriptional regulation of the PEPCK gene has been extensively studied. CREM is the transcription factor that bind efficiently to the putative cyclic AMP response element (CRE) in PEPCK gene. Several other transcription factors can bind to this element and activate transcription. In oviparous animals, such as bovine tick R. microplus, the embryonic development occurs outside the maternal organism, implying that all the nutrients necessary for embryogenesis must be present in the oocytes. We observed the relationship between the main energy sources and the morphogenetic changes that occur during R. microplus tick embryogenesis. Energy homeostasis is maintained by glycogen mobilization in the beginning of embryogenesis, as its content is drastically decreased during the first five days of development. Afterwards, the activity of the gluconeogenesis enzyme PEPCK increases enormously, as indicated by a concomitant increase in glucose content (Moraes et al., 2007). Here, we analyzed PEPCK gene transcription by qPCR during the embryogenesis and starvation larvae. The PEPCK transcription was higher at first and 15th day eggs of the development. In larvae the levels of PEPCK transcripts is increased at fifth day after hatch. However, the activity is continuous increased in larvae the form first up to 15th day. Now we are investigating the involvement of CREM in the PEPCK gene transcription in these cells. In this sense, we obtained CREM sequence from TIGR ESTs R. microplus bank and designed the specific primers to qPCR. Taken together our results suggest the involvement of PEPCK to the

  15. Exploring the use of an anti-tick vaccine as a tool for the integrated eradication of the cattle fever tick, Rhipicephalus (Boophilus) annulatus.

    Science.gov (United States)

    Miller, Robert; Estrada-Peña, Agustín; Almazán, Consuelo; Allen, Andrew; Jory, Lauren; Yeater, Kathleen; Messenger, Matthew; Ellis, Dee; Pérez de León, Adalberto A

    2012-08-17

    Bovine babesiosis, also known as cattle fever, is a tick-borne protozoal disease foreign to the United States. It was eradicated by eliminating the vector species, Rhipicephalus (Boophilus) annulatus and Rhipicephalus (Boophilus) microplus, through the efforts of the Cattle Fever Tick Eradication Program (CFTEP), with the exception of a permanent quarantine zone (PQZ) in south Texas along the border with Mexico. Keeping the U.S. free of cattle fever ticks in a sustainable manner is a critical national agricultural biosecurity issue. The efficacy of a Bm86-based anti-tick vaccine commercialized outside of the U.S. was evaluated against a strain of R. annulatus originated from an outbreak in Texas. Vaccination controlled 99.9 and 91.4% of the ticks 8 weeks and 5.5 months after the initial vaccination, respectively. Computer modeling of habitat suitability within the PQZ typically at risk of re-infestation with R. annulatus from Mexico predicted that at a level of control greater than 40%, eradication would be maintained indefinitely. Efficacy and computer modeling data indicate that the integration of vaccination using a Bm86-based anti-tick vaccine with standard eradication practices within the northwestern half of the PQZ could incentivize producers to maintain cattle on pasture thereby avoiding the need to vacate infested premises. Implementing this epidemiologically proactive strategy offers the opportunity to prevent R. annulatus outbreaks in the U.S., which would represent a significant shift in the way the CFTEP operates. PMID:22687762

  16. Humoral immune response of dairy cattle immunized with rBm95 (KU-VAC1) derived from Thai Rhipicephalus microplus.

    Science.gov (United States)

    Jittapalapong, S; Kaewhom, P; Kengradomkij, C; Saratapan, N; Canales, M; de la Fuente, J; Stich, R W

    2010-04-01

    Rhipicephalus (Boophilus) microplus is an important cause of economic losses in Thailand through direct effects of feeding on cattle and pathogen transmission. Current tick control methods rely on expensive chemical acaricides that result in environmental contamination, residues in food animal products and acaricide-resistant ticks. Anti-tick vaccines based on concealed antigens have shown promising results in the control of cattle tick. Thus, recombinant Bm95 (rBm95) from Thai R. microplus (KU-VAC1) was cloned and expressed to test as an anti-tick vaccine in Thailand. The objective of this study was to compare antibody responses induced by KU-VAC1 to that obtained after vaccination with Gavac that is based on the Bm86 homologue. Four groups of six cattle each were immunized with KU-VAC1, Gavac, adjuvant or phosphate-buffered saline, and boosted three times at 21-day intervals. Enzyme-linked-immunosorbent serologic assay were used to measure the humoral antibody responses specific to Thai rBm95. Cattle immunized with either KU-VAC1 or Gavac showed significantly greater antibody production than the controls. Antibody titres were detected after the first immunization and peaked after the seventh week. These results indicated that KU-VAC1 and Gavac are similarly immunogenic, and that further studies are warranted to compare performance parameters of ticks fed on immunized cattle. PMID:20537117

  17. A treatment with a protease inhibitor recombinant from the cattle tick (Rhipicephalus Boophilus microplus ameliorates emphysema in mice.

    Directory of Open Access Journals (Sweden)

    Juliana D Lourenço

    Full Text Available AIMS: To determine whether a serine protease inhibitor treatment can prevent or minimize emphysema in mice. METHODS: C57BL/6 mice were subjected to porcine pancreatic elastase (PPE nasal instillation to induce emphysema and were treated with a serine protease inhibitor (rBmTI-A before (Protocol 1 and after (Protocol 2 emphysema development. In both protocols, we evaluated lung function to evaluate the airway resistance (Raw, tissue damping (Gtis and tissue elastance (Htis. The inflammatory profile was analyzed in the bronchoalveolar lavage (BALF and through the use of morphometry; we measured the mean linear intercept (Lm (to verify alveolar enlargement, the volume proportion of collagen and elastic fibers, and the numbers of macrophages and metalloprotease 12 (MMP-12 positive cells in the parenchyma. We showed that at both time points, even after the emphysema was established, the rBmTI-A treatment was sufficient to reverse the loss of elastic recoil measured by Htis, the alveolar enlargement and the increase in the total number of cells in the BALF, with a primary decrease in the number of macrophages. Although, the treatment did not control the increase in macrophages in the lung parenchyma, it was sufficient to decrease the number of positive cells for MMP-12 and reduce the volume of collagen fibers, which was increased in PPE groups. These findings attest to the importance of MMP-12 in PPE-induced emphysema and suggest that this metalloprotease could be an effective therapeutic target.

  18. Effect of the association of cattle and rusa deer (Cervus timorensis russa) on populations of cattle ticks (Boophilus microplus).

    Science.gov (United States)

    Barre, N; Bianchi, M; De Garine-Wichatitsky, M

    2002-10-01

    The wild population of rusa deer (Cervus timorensis russa) in New Caledonia (South Pacific) is nearly as large as the cattle population. The cattle tick is widespread and occurs all year round. Opinions are divided on the role of deer in the biological cycle of the tick: i) Do they maintain a sustainable tick population that is secondarily available for cattle? ii) Do they decrease the infestation of the environment by collecting larvae on the pasture, but preventing their development to the engorged female stage? or iii) Do they contribute to both situations? An experiment was conducted in three groups of pastures, each seeded with 450 000 larvae/ha and allowed to be grazed only by cattle, only by deer, and by a mixed herd of deer and cattle (deer representing 30% of the biomass), at approximately the same stocking rate (470-510 kg/ha). After 15 months of exposure, the tick burden per weight unit of host was 42 ticks/kg for the steers-only herd and 0.01/kg for the deer-only herd. The steers in the "mixed group" harbored 7 times fewer ticks (6.2/kg) than the cattle-only group, and the deer in the "mixed group," 130 times more (1.3/kg) than the deer-only group. Five emergency acaricide treatments had to be applied in the cattle-only group, but none in the other groups. The long-term sustainability of a viable tick population on deer as well as the potential benefit resulting from the association of deer and susceptible cattle in the tick control of cattle are highlighted. PMID:12381606

  19. Bm86 antigen induces a protective immune response against Boophilus microplus following DNA and protein vaccination in sheep.

    Science.gov (United States)

    De Rose, R; McKenna, R V; Cobon, G; Tennent, J; Zakrzewski, H; Gale, K; Wood, P R; Scheerlinck, J P; Willadsen, P

    1999-11-30

    Vaccination of sheep with a plasmid bearing the full length gene for the tick antigen Bm86 either alone or co-administered with plasmid carrying the ovine genes for the cytokines, granulocyte and macrophage colony stimulating factor (GM-CSF) or interleukin (IL)-1beta induced a relatively low level of protection against subsequent tick infestation. This tick damage reached statistical significance only for the groups which were vaccinated with plasmid encoding for Bm86, co-administered with plasmid encoding for ovine GM-CSF. Antibody titres measured against Bm86 were also low in all groups injected with the Bm86 DNA vaccine. Antibody production and anti-tick effect were significantly less than that achieved by two vaccinations with recombinant Bm86 protein. In all cases only a low level of antigen-specific stimulation of peripheral blood lymphocytes was recorded, as measured either by the incorporation of tritiated thymidine or the release of IFN-gamma. Injection of DNA encoding for Bm86, either alone or with co-administered cytokine genes, did however prime for a strong subsequent antibody response following a single injection of recombinant Bm86 protein in adjuvant. Antibody production nevertheless appeared to be slightly less effective than following two vaccinations with recombinant protein. The persistence of antibody following vaccination was the same regardless of the method of primary sensitization. In all cases the half-life of the antibody response was approximately 40-50 days indicating that, in contrast to results reported in mice, DNA vaccination in sheep did not result in sustained antibody production. PMID:10587297

  20. Reduced Efficacy of Commercial Acaricides Against Populations of Resistant Cattle Tick Rhipicephalus microplus from Two Municipalities of Antioquia, Colombia.

    Science.gov (United States)

    Lopez-Arias, Anderson; Villar-Argaiz, David; Chaparro-Gutierrez, Jenny J; Miller, Robert J; Perez de Leon, Adalberto A

    2014-01-01

    Two distant Antioquian cattle farms where systemic and topical acaricides had previously failed to control infestations by Rhipicephalus (Boophilus) microplus were studied. An initial in vivo study was conducted using single subcutaneous injections with a long-acting formulation of ivermectin (630 μg/kg). Injections were made at 3-month intervals on animals at each farm to evaluate the therapeutic and persistent efficacy of ivermectin against R. microplus. Body tick counts and reproductive parameters of semi- or fully engorged females (≥5 mm) were assessed at 10-day intervals, and since no negative control group could be included, values were compared against those for day 0. Although there was an overall reduction of 50%-75% in tick numbers that persisted for 30-40 days, it was not significantly different at one of the farms and not enough to afford protection from severe infestations. The engorgement weight and egg mass weight of ticks from treated animals were significantly lower throughout the 50-day posttreatment period. Egg hatch was not significantly reduced posttreatment and remained at levels of 80%-90%. A random selection of 9 out of 28 commercial formulations of ivermectin sold in Colombia were analyzed by High Performance Liquid Chromatography (HPLC). All were within the expected labeled concentration (±15% deviation) of 1% and 3.15% ivermectin except for one. A popular unregistered injectable widely used in both farms and labeled as "natural pyrethrin", was found to contain 10.5% ivermectin. An adult immersion test was conducted to evaluate the efficacy of topical acaricides to recommended concentrations of five commercial products and/or their combinations. Efficacy was determined by comparing the reproductive index of each treated group to that of the control group. Cypermethrin (150 ppm) was completely ineffective at both farms. Amitraz (208 ppm) exhibited low and intermediate efficacies of 14% and 56%. The combination of amitraz (100 ppm) and

  1. A GPCR-focused investigation of the R. microplus transcriptome

    Science.gov (United States)

    Rhipicephalus microplus, also known as the southern cattle tick, has been found in tropical and subtropical regions all over the world, including Mexico. It is a vector for parasites responsible for cattle diseases that can lead to decreased weight, anemia, loss of milk/meat production, and death. T...

  2. Generation of full-length cDNAs for eight putative GPCnR from the cattle tick, R. microplus using a targeted degenerate PCR and sequencing strategy.

    Directory of Open Access Journals (Sweden)

    Sean W Corley

    Full Text Available We describe here a rapid and efficient method for the targeted isolation of specific members of gene families without the need for cloning. Using this strategy we isolated full length cDNAs for eight putative G-protein coupled neurotransmitter receptors (GPCnR from the cattle tick Rhipicephalus (Boophilus microplus. Gene specific degenerate primers were designed using aligned amino acid sequences of similar receptor types from several insect and arachnid species. These primers were used to amplify and sequence a section of the target gene. Rapid amplification of cDNA ends (RACE PCR was used to generate full length cDNA sequences. Phylogenetic analysis placed 7 of these sequences into Class A G-protein coupled receptors (GPCR (Rm_α2AOR, Rm_β2AOR, Rm_Dop1R, Rm_Dop2R, Rm_INDR, Rm_5-HT(7R and Rm_mAchR, and one into Class C GPCR (Rm_GABA(BR. Of the 7 Class A sequences, only Rm_mAchR is not a member of the biogenic amine receptor family. The isolation of these putative receptor sequences provides an opportunity to gain an understanding of acaricide resistance mechanisms such as amitraz resistance and might suggest possibilities for the development of new acaricides.

  3. Assessment of bovine immunoprotecion against Rhipicephalus microplus using Bm86-CG antigen expressed in Pichia pastoris

    Science.gov (United States)

    The cattle tick Rhipicephalus microplus is a major pest of cattle in tropical and subtropical parts of the world. In addition to direct effects associated with its obligate parasitic way of life, R. microplus also transmits the pathogens that cause bovine babesiosis and anaplasmosis. Commercially ...

  4. Acaricide activity in vitro of Acmella oleracea against Rhipicephalus microplus.

    Science.gov (United States)

    Castro, K N C; Lima, D F; Vasconcelos, L C; Leite, J R S A; Santos, R C; Paz Neto, A A; Costa-Júnior, L M

    2014-10-01

    Cattle tick control has been limited by the resistance of these parasites to synthetic acaricides. Natural products are a possible alternative as they have different mechanisms of action. Acmella oleracea is a native plant with a large cultivated area in the Amazon region and could be easily used for large-scale preparation of a commercial product. This study evaluated the in vitro action of the hexane extract of the aerial parts of A. oleracea on larvae and engorged females of the cattle tick Rhipicephalus microplus. Spilanthol was the major constituent with a content of 14.8% in the extract. The hexane extract of A. oleracea was highly effective against larvae of R. microplus with an LC50 of 0.8 mg mL(-1). Against engorged females, hexane extract of A. oleracea reduced oviposition and hatchability of eggs with an LC50 of 79.7 mg mL(-1). Larvae and engorged females were killed by the hexane extract with high efficiency (>95%) at concentrations of 3.1 and 150.0 mg mL(-1), respectively. These results demonstrate that the hexane extract of A. oleracea has significant activity against R. microplus and has potential to be developed into formulations for tick control. PMID:25033813

  5. High efficacy of a 20 amino acid peptide of the acidic ribosomal protein P0 against the cattle tick, Rhipicephalus microplus.

    Science.gov (United States)

    Rodríguez-Mallon, Alina; Encinosa, Pedro E; Méndez-Pérez, Lídice; Bello, Yamil; Rodríguez Fernández, Rafmary; Garay, Hilda; Cabrales, Ania; Méndez, Luis; Borroto, Carlos; Estrada, Mario Pablo

    2015-06-01

    Current strategies to control cattle ticks use integrated control programs (ICP) that include vaccination. Reduction in the use of chemicals and in the cost of tick control, the delay or elimination of acaricide resistance and the decreasing of environmental pollution are the advantages of using these programs. This integrated program is potentially applicable to all genotypes of chemical resistant ticks. However, the problem here is to improve the efficacy of anti-tick vaccines. The P0 protein is a structural component of the ribosome of all organisms. We have identified an immunogenic region of ribosomal protein P0 from Rhipicephalus spp. ticks that is not very conserved compared to the orthologous protein in their hosts. A synthetic 20 amino acid peptide from this sequence was effective as a vaccine against Rhipicephalus sanguineus infestations in an immunization and challenge experiment using rabbits. In this paper, the same peptide used as vaccine against the cattle tick Rhipicephalus Boophilus microplus shows a significant diminution in the number of engorged females recovered, in the weight of females and the weight of egg masses. The number of eggs hatched was also significantly reduced for the vaccinated group, with an overall effectivity for the antigen pP0 of 96%. These results, together with the conserved sequence of the P0 peptide among ticks, suggest that this antigen could be a good broad spectrum vaccine candidate. It would be expected to be active against many species of ticks and thus has promise in an ICP for effective control of ticks and thereby to improve the efficiency and productivity of the livestock industry. PMID:25958782

  6. Virulence of Isaria sp. and Purpureocillium lilacinum to Rhipicephalus microplus tick under laboratory conditions.

    Science.gov (United States)

    Angelo, Isabele C; Fernandes, Éverton K K; Bahiense, Thiago C; Perinotto, Wendell M S; Golo, Patricia S; Moraes, Ana Paula R; Bittencourt, Vânia R E P

    2012-10-01

    Rhipicephalus microplus (Canestrini) is an ectoparasite accountable for great economic losses. The use of entomopathogenic fungi to control arthropods has shown promising responses. The present study evaluated the virulence of Isaria farinosa (Holmsk.) Fr., Isaria fumosorosea (Wize) Brown and Smith, and Purpureocillium lilacinum (=Paecilomyces lilacinus) (Thom.) Samson to engorged females, eggs, and larvae of R. microplus. There were four treatment groups (10(5), 10(6), 10(7), and 10(8) conidia ml(-1)) and the control group (water and Tween 80, 0.1% v/v). The treatment was based on immersion of the specimen in 1 ml of the suspension or control solution. The study observed changes in egg viability and larval mortality after treatment. The results showed that I. farinosa, P. lilacinum, and I. fumosorosea caused alterations in the biological parameters of R. microplus ticks. I. fumosorosea presented the greatest potential to control R. microplus engorged females in vitro, causing a 49% decrease in nutritional index. All fungal isolates presented significant reduction in the egg production index. I. farinosa reduced the hatching percentage if the eggs were treated with the two highest conidial concentrations. All conidial concentrations of I. fumosorosea were able to reduce the hatching percentage significantly. All tested isolates showed pathogenicity toward unfed R. microplus larvae. As far as we know, this is the first study reporting the effect in vitro of I. farinosa, I. fumosorosea, and P. lilacinum to different developmental stages of R. microplus ticks. PMID:22710525

  7. Acaricidal efficacies of Lippia gracilis essential oil and its phytochemicals against organophosphate-resistant and susceptible strains of Rhipicephalus (Boophilus) microplus

    Science.gov (United States)

    Plant-derived natural products can serve as an alternative to synthetic compounds for control of ticks of veterinary and medical importance. Lippia gracilis is an aromatic plant that produces essential oil with high content of carvacrol and thymol monoterpenes. These monoterpenes have high acaricida...

  8. Assessing bovine babesiosis in Rhipicephalus (Boophilus microplus ticks and 3 to 9-month-old cattle in the middle Magdalena region, Colombia

    Directory of Open Access Journals (Sweden)

    Sandra Ríos-Tobón

    2014-04-01

    Full Text Available Babesia sp. is a protozoan hemoparasite that affects livestock worldwide. The Colombian Middle Magdalena is an enzootic region for babesiosis, but there is no previous research providing detail on its transmission cycle. This study aims to assess some Babesia sp. infection indicators in cattle and ticks from the area, by using direct microscopic and molecular techniques to detect the infection. In the cattle, 59.9% and 3.4 % positivity values for B. bigemina and mixed infection (B. bovis + B. bigemina were found respectively. In ticks, the positivity of B. bigemina reached 79.2% and 9.4% for the mixed infection. The degree of infestation in the region was 3.2 ticks per bovine. There was positive correlation between tick control acaricide frequencies and infestation in bovines. This leads us to infer that control periodicity greater than 90 days, in stable zones, is an abiotic factor that benefits the acquisition of protective immunity in calves, the natural control of the infection and eventual disease absence. It is necessary to monitor the disease by applying new entomological and parasitological indicators showing the complexity of this phenomenon.

  9. Mapping of quantitative trait loci controlling tick [Riphicephalus (Boophilus) microplus] resistance on bovine cjrp,psp,es 5, 7 and 14

    Science.gov (United States)

    Since Bos taurus and Bos indicus cattle breeds have diverged at approximately 10.000 years ago, the differences in the process of domestication and subsequent selection for desired phenotypes is presumed to have contributed the phenotypic and genetic differences between these subspecies. Of particu...

  10. The penultimate arginine of the carboxy terminus determines slow desensitisation in a P2X receptor from the cattle tick Boophilus microplus

    Science.gov (United States)

    P2X ion channels have been functionally characterised from a range of eukaryotes. Whilst these receptors can be broadly classified into fast and slow desensitising, the molecular mechanisms underlying current desensitisation are not fully understood. Here we describe the characterisation of a P2X ch...

  11. 微小牛蜱Bm86基因的真核表达%Eukaryotic expression of Bm86 gene of Boophilus microplus in Pichia pastoris

    Institute of Scientific and Technical Information of China (English)

    李文卉; 任巧云; 罗建勋; 殷宏; 关贵全; 马米玲; 刘志杰; 刘爱红; 党志胜; 高金亮

    2005-01-01

    采用RT-PCR技术从微小牛蜱饥饿幼蜱破解物中扩增到Bm86基因,将其与巴斯德毕赤酵母分泌型表达载体pPIC9K重组构建了重组表达载体pPIC9K-Bm86,测序正确后将其用SacⅠ内切酶线性化后采用电穿孔法转化巴斯德毕赤酵母菌GS115,经G418抗性筛选高拷贝重组菌株后用甲醇诱导表达,SDS-PAGE和Western-blotting分析结果表明,诱导表达的培养上清液中表达出具有反应活性的68 ku重组Bm86蛋白,目的蛋白约占培养上清液中蛋白总量的32%以上,诱导96 h目的蛋白的表达量为0.36 mg/mL.

  12. Selection of reference genes for quantitative RT-PCR studies in Rhipicephalus (Boophilus) microplus and Rhipicephalus appendiculatus ticks and determination of the expression profile of Bm86

    OpenAIRE

    Jongejan Frans; Postigo Milagros; Balk Jesper A; Nijhof Ard M

    2009-01-01

    Abstract Background For accurate and reliable gene expression analysis, normalization of gene expression data against reference genes is essential. In most studies on ticks where (semi-)quantitative RT-PCR is employed, normalization occurs with a single reference gene, usually β-actin, without validation of its presumed expression stability. The first goal of this study was to evaluate the expression stability of commonly used reference genes in Rhipicephalus appendiculatus and Rhipicephalus ...

  13. Comparison of predicted binders in Rhipicephalus (Boophilus) microplus intestine protein variants Bm86 Campo Grande strain, Bm86 and Bm95.

    Science.gov (United States)

    Andreotti, Renato; Pedroso, Marisela S; Caetano, Alexandre R; Martins, Natália F

    2008-01-01

    This paper reports the sequence analysis of Bm86 Campo Grande strain comparing it with Bm86 and Bm95 antigens from the preparations TickGardPLUS and Gavac, respectively. The PCR product was cloned into pMOSBlue and sequenced. The secondary structure prediction tool PSIPRED was used to calculate alpha helices and beta strand contents of the predicted polypeptide. The hydrophobicity profile was calculated using the algorithms from the Hopp and Woods method, in addition to identification of potential MHC class-I binding regions in the antigens. Pair-wise alignment revealed that the similarity between Bm86 Campo Grande strain and Bm86 is 0.2% higher than that between Bm86 Campo Grande strain and Bm95 antigens. The identities were 96.5% and 96.3% respectively. Major suggestive differences in hydrophobicity were predicted among the sequences in two specific regions. PMID:18823577

  14. Boophilus microplus: estado actual de la resistencia a los acaricidas en la frontera México Estados Unidos y su impacto en la relación comercial

    OpenAIRE

    Juan Ramón González Sáenz Pardo; Rubén Hernández Ortiz

    2012-01-01

    Se aborda la importancia de las exportaciones de ganado bovino en pie a los Estados Unidos de América, destacando el valor comercial que representa para México la entrada de divisas por 700 millones USD anuales por este concepto. La comercialización de ganado se ve frenada por barreras no arancelarias, tales como la tuberculosis (TB), brucelosis y las garrapatas. Se ha formado un grupo binacional de expertos para tratar estos temas. En el tema de garrapatas se han establecido sistemas de cola...

  15. Cellular responses to Rhipicephalus microplus infestations in pre-sensitised cattle with differing phenotypes of infestation.

    Science.gov (United States)

    Marufu, Munyaradzi C; Dzama, Kennedy; Chimonyo, Michael

    2014-02-01

    The blue tick, Rhipicephalus microplus, threatens cattle production in most tropical and subtropical areas of the world. Delayed skin hypersensitivity reactions are thought to cause Nguni cattle to be more resistant to R. microplus than Bonsmara cattle yet the cellular mechanisms responsible for these differences have not been classified. Tick counts and inflammatory cell infiltrates in skin biopsies from feeding sites of adult R. microplus ticks were determined in 9-month-old Nguni and Bonsmara heifers to determine the cellular mechanisms responsible for tick immunity. Nguni heifers (1.7 ± 0.03) had lower (P tick counts than the Bonsmaras (2.0 ± 0.03). Parasitized sites in Nguni heifers had higher counts of basophils, mast and mononuclear cells than those in the Bonsmara heifers. Conversely, parasitized sites in Nguni heifers had lower neutrophil and eosinophil counts than those in the Bonsmara heifers. Tick count was negatively correlated with basophil and mast cell counts and positively correlated with eosinophil counts in both breeds. In the Bonsmara breed, tick count was positively correlated with mononuclear cell counts. Cellular responses to adult R. microplus infestations were different and correlated with differences in tick resistance in Nguni and Bonsmara cattle breeds. It is essential to further characterise the molecular composition of the inflammatory infiltrate elicited by adult R. microplus infestation to fully comprehend immunity to ticks in cattle. PMID:24057115

  16. An integrative approach to understanding pyrethroid resistance in Rhipicephalus microplus and R. decoloratus ticks.

    Science.gov (United States)

    Wyk, Roelof Dj van; Baron, Samantha; Maritz-Olivier, Christine

    2016-06-01

    Rhipicephalus microplus and Rhipicephalus decoloratus species occur in regions with savannah and temperate climates, typically in grassland and wooded areas used as cattle pasture. Both species are associated with the transmission of Anaplasma and Babesia spp., impacting livestock health and quality of livestock-associated products. In Africa, tick control is predominantly mediated with the use of acaricides, such as synthetic pyrethroids. After several years on the market, reports of resistance to synthetic pyrethroids escalated but limited field data and validation studies have been conducted to determine the extent of acaricide resistance in Africa. Without this data, knowledge-based tick control will remain problematic and selection pressure will remain high increasing the rate of resistance acquisition. To date, several pyrethroid resistance associated single nucleotide polymorphisms (SNPs) have been reported for arthropods within the voltage-gated sodium channel. Three SNPs have been identified within this channel in pyrethroid resistant R. microplus ticks, but none has been reported for R. decoloratus. This study is the first to report the presence of a shared SNP within the voltage-gated sodium channel in both R. microplus and R. decoloratus, which is directly linked to pyrethroid resistance in R. microplus. As the mode of action by which these SNPs mediate pyrethroid resistance remains unknown, this study aims to set hypotheses by means of predictive structural modelling. This not only paves the way forward to elucidating the underlying biological mechanisms involved in pyrethroid resistance, but also improvement of existing acaricides and ultimately sustainable tick control management. PMID:26851840

  17. Role of Rhipicephalus microplus cheliceral receptors in gustation and host differentiation

    Science.gov (United States)

    Rhipicephalus microplus is considered the most economically important ectoparasite of cattle worldwide. It is known that zebuine breeds of cattle are less susceptible to tick infestation than taurine breeds. Contact chemoreceptors in the cheliceral pit sensilla of ticks respond selectively to phagos...

  18. SNP Analysis Infers that Recombination Is Involved in the Evolution of Amitraz Resistance in Rhipicephalus microplus.

    Science.gov (United States)

    Baron, Samantha; van der Merwe, Nicolaas A; Madder, Maxime; Maritz-Olivier, Christine

    2015-01-01

    Rhipicephalus microplus, better known as the Asiatic cattle tick, is a largely invasive ectoparasite of great economic importance due to the negative effect it has on agricultural livestock on a global scale, particularly cattle. Tick-borne diseases (babesiosis and anaplasmosis) transmitted by R. microplus are alarming as they decrease the quality of livestock health and production. In sub-Saharan Africa, cattle represent a major source of meat and milk, but this region of the world is severely affected by the Rhipicephalus microplus tick. The principal method for tick control is the use of chemical acaricides, notably amitraz, which was implemented in the 1990's after resistance to other acaricides surfaced. However, the efficiency of chemical control is hindered by an increase in the frequency of mutant resistance alleles to amitraz in tick populations. Presently, the only way to assess amitraz resistance is by means of larval packet tests, but this technique is time-consuming and not particularly cost effective. The main aims of this study were three-fold. First, we attempted to correlate two known SNPs in the octopamine/tyramine (OCT/Tyr) receptor with amitraz resistance in South African field samples of R. microplus. Second, we calculated gametic disequilibrium for these SNPs to determine whether they are randomly associated. Lastly, we conducted a study to assess the evolutionary effects of recombination within the OCT/Tyr receptor. Our results confirmed that the two SNPs are associated with amitraz resistance in the South African tick strain, and that they are in gametic disequilibrium. Additionally, recombination was detected in the OCT/Tyr receptor generating two recombinant haplotypes. These results are of concern to farmers in sub-Saharan Africa, and the emergence of amitraz resistance should be closely monitored in future. Therefore, we present a quick and affordable RFLP based diagnostic technique to assess amitraz resistance in field samples of R

  19. Role of Rhipicephalus microplus cheliceral receptors in gustation and host differentiation.

    Science.gov (United States)

    Ferreira, Lorena Lopes; Soares, Sara Fernandes; de Oliveira Filho, Jaires Gomes; Oliveira, Thaynara Tatielly; Pérez de León, Adalberto A; Borges, Lígia Miranda Ferreira

    2015-04-01

    Rhipicephalus microplus is considered the most economically important ectoparasite of cattle worldwide. It is known that zebuine breeds of cattle are less susceptible to tick infestation than taurine breeds. Contact chemoreceptors in the cheliceral pit sensilla of ticks respond selectively to phagostimulant compounds, however their role in blood feeding relative to host susceptibility to infestation remains to be fully understood. We addressed this topic by conducting taste electrophysiology experiments with cheliceral pit sensilla preparations of R. microplus females. Solutions of five known ixodid tick phagostimulants were tested at different concentrations: sodium (NaCl), and potassium chloride (KCl) (10(-3)-10(-1)M); glucose (10(-4)-10(-1)M); adenosine triphosphate (ATP) (10(-6)-10(-2)M); and reduced l-glutathione (GSH) (10(-6)-10(-2)M). Serum samples from six susceptible animals of the Girolando breed (5/8 Bos indicus×3/8 B. taurus) and six resistant Nelore bovines (pure B. indicus) were also tested. A dose-dependent response of gustatory neurons associated with the chelicerae sensillum to NaCl, glucose, GSH, and ATP were observed. Responses by the cheliceral inner digit pit sensilla of R. microplus to KCl and glucose were also observed and they are reported here for the first time. In addition to an electrophysiological response to known phagostimulants, chemoreceptors in the chelicera of R. microplus responded differently to serum from cattle susceptible and resistant to infestation. The cheliceral pit neurons were more responsive to serum of R. microplus resistant bovines with a higher mean spike frequency (53.5±2spikess(-1)) than to serum samples from susceptible cattle (40.3±2spikess(-1)). The implications of chemosensation during tick blood feeding are discussed.

  20. SNP Analysis Infers that Recombination Is Involved in the Evolution of Amitraz Resistance in Rhipicephalus microplus.

    Directory of Open Access Journals (Sweden)

    Samantha Baron

    Full Text Available Rhipicephalus microplus, better known as the Asiatic cattle tick, is a largely invasive ectoparasite of great economic importance due to the negative effect it has on agricultural livestock on a global scale, particularly cattle. Tick-borne diseases (babesiosis and anaplasmosis transmitted by R. microplus are alarming as they decrease the quality of livestock health and production. In sub-Saharan Africa, cattle represent a major source of meat and milk, but this region of the world is severely affected by the Rhipicephalus microplus tick. The principal method for tick control is the use of chemical acaricides, notably amitraz, which was implemented in the 1990's after resistance to other acaricides surfaced. However, the efficiency of chemical control is hindered by an increase in the frequency of mutant resistance alleles to amitraz in tick populations. Presently, the only way to assess amitraz resistance is by means of larval packet tests, but this technique is time-consuming and not particularly cost effective. The main aims of this study were three-fold. First, we attempted to correlate two known SNPs in the octopamine/tyramine (OCT/Tyr receptor with amitraz resistance in South African field samples of R. microplus. Second, we calculated gametic disequilibrium for these SNPs to determine whether they are randomly associated. Lastly, we conducted a study to assess the evolutionary effects of recombination within the OCT/Tyr receptor. Our results confirmed that the two SNPs are associated with amitraz resistance in the South African tick strain, and that they are in gametic disequilibrium. Additionally, recombination was detected in the OCT/Tyr receptor generating two recombinant haplotypes. These results are of concern to farmers in sub-Saharan Africa, and the emergence of amitraz resistance should be closely monitored in future. Therefore, we present a quick and affordable RFLP based diagnostic technique to assess amitraz resistance in field

  1. Role of Rhipicephalus microplus cheliceral receptors in gustation and host differentiation.

    Science.gov (United States)

    Ferreira, Lorena Lopes; Soares, Sara Fernandes; de Oliveira Filho, Jaires Gomes; Oliveira, Thaynara Tatielly; Pérez de León, Adalberto A; Borges, Lígia Miranda Ferreira

    2015-04-01

    Rhipicephalus microplus is considered the most economically important ectoparasite of cattle worldwide. It is known that zebuine breeds of cattle are less susceptible to tick infestation than taurine breeds. Contact chemoreceptors in the cheliceral pit sensilla of ticks respond selectively to phagostimulant compounds, however their role in blood feeding relative to host susceptibility to infestation remains to be fully understood. We addressed this topic by conducting taste electrophysiology experiments with cheliceral pit sensilla preparations of R. microplus females. Solutions of five known ixodid tick phagostimulants were tested at different concentrations: sodium (NaCl), and potassium chloride (KCl) (10(-3)-10(-1)M); glucose (10(-4)-10(-1)M); adenosine triphosphate (ATP) (10(-6)-10(-2)M); and reduced l-glutathione (GSH) (10(-6)-10(-2)M). Serum samples from six susceptible animals of the Girolando breed (5/8 Bos indicus×3/8 B. taurus) and six resistant Nelore bovines (pure B. indicus) were also tested. A dose-dependent response of gustatory neurons associated with the chelicerae sensillum to NaCl, glucose, GSH, and ATP were observed. Responses by the cheliceral inner digit pit sensilla of R. microplus to KCl and glucose were also observed and they are reported here for the first time. In addition to an electrophysiological response to known phagostimulants, chemoreceptors in the chelicera of R. microplus responded differently to serum from cattle susceptible and resistant to infestation. The cheliceral pit neurons were more responsive to serum of R. microplus resistant bovines with a higher mean spike frequency (53.5±2spikess(-1)) than to serum samples from susceptible cattle (40.3±2spikess(-1)). The implications of chemosensation during tick blood feeding are discussed. PMID:25616714

  2. Comparison of predicted binders in Rhipicephalus (Boophilus) microplus intestine protein variants BM86 Campo Grande strain, BM86 and BM95 Comparação da previsão de ligação das variantes de proteína de intestino de Rhipicephalus (Boophilus) microplus Bm86 cepa Campo Grande, Bm86 e Bm95

    OpenAIRE

    Renato Andreotti; Marisela S. Pedroso; Caetano, Alexandre R; Natália F. Martins

    2008-01-01

    This paper reports the sequence analysis of Bm86 Campo Grande strain comparing it with Bm86 and Bm95 antigens from the preparations TickGardPLUS and GavacTM, respectively. The PCR product was cloned into pMOSBlue and sequenced. The secondary structure prediction tool PSIPRED was used to calculate alpha helices and beta strand contents of the predicted polypeptide. The hydrophobicity profile was calculated using the algorithms from the Hopp and Woods method, in addition to identification of po...

  3. Sequence variation of Bm86 in cattle fever ticks isolated from outbreaks in south Texas

    Science.gov (United States)

    The prevalence of Rhipicephalus (Boophilus) microplus and Rhipicephalus (Boophilus) annulatus cattle infestations have significantly expanded beyond the original quarantine zone established in south Texas as part of the Cattle Fever Tick Eradication Program. Major obstacles for containment of ticks...

  4. Acaricidal effect of Cassia fistula Linn. leaf ethanolic extract against Rhipicephlaus (Boophilus) annulatus.

    Science.gov (United States)

    Sunil, A R; Amithamol, K K; Juliet, S; Nair, S N; Ajithkumar, K G; Soorya, V C; Divya, T M; Jyothymol, G; Ghosh, S; Ravindran, R

    2013-06-01

    The present study evaluates the acaricidal properties of crude ethanolic extract of Cassia fistula leaves for controlling Rhipicephalus (Boophilus) annulatus based on adult immersion test (AIT). The percentage of adult mortality, inhibition of fecundity and hatching of ova laid were studied at different concentrations of the extract ranging from 50 to 100 mg / ml. The results were compared using one-way ANOVA. The extract produced complete inhibition of hatching of eggs at concentrations above 80 mg / ml of the extract. Mortality of adult engorged female ticks and inhibition of fecundity were concentration dependent. The LC50 value of extract against R. (B.) annulatus was 97.1 mg / ml.

  5. In vitro acaricidal efficacy of plant extracts from Brazilian flora and isolated substances against Rhipicephalus microplus (Acari: Ixodidae).

    Science.gov (United States)

    Valente, Paula Pimentel; Amorim, Juliana Mendes; Castilho, Rachel Oliveira; Leite, Romário Cerqueira; Ribeiro, Múcio Flávio Barbosa

    2014-01-01

    The tick Rhipicephalus microplus causes significant losses in livestock cattle and has developed increasing resistance to the primary acaricides that are used to treat these infections. The objective of this study was to identify new biomolecules or isolated substances showing acaricidal activity from plants. Larval packet tests were conducted to evaluate the effects of 11 species of plants and three isolated substances (betulinic acid, eugenol, and nerolidol) on R. microplus. An adult female immersion test was performed with the substance that showed the highest larvicidal activity, which was evaluated for inhibition of reproduction. Tests using Licania tomentosa, Hymenaea stigonocarpa, Hymenaea courbaril, Stryphnodendron obovatum, Jacaranda cuspidifolia, Jacaranda ulei, Struthanthus polyrhizus, Chrysobalanus icaco, Vernonia phosphorea, Duguetia furfuracea, and Simarouba versicolor extracts as well as the isolated substance betulinic acid indicated lower acaricidal effects on R. microplus larvae. The extract displaying the best larvicidal activity was the ethanolic extract from L. tomentosa at a concentration of 60%, resulting in a mortality rate of 40.3%. However, nerolidol and eugenol showed larvicidal activity, which was highest for eugenol. Nerolidol caused a 96.5% mortality rate in the R. microplus larvae at a high concentration of 30%, and eugenol caused 100% mortality at a concentration of 0.3%. In the adult immersion test, 5% eugenol was identified as a good biomolecule for controlling R. microplus, as demonstrated by its high acaricidal activity and inhibition of oviposition. PMID:24221889

  6. Immunoregulation of bovine macrophages by factors in the salivary glands of Rhipicephalus microplus

    Directory of Open Access Journals (Sweden)

    Brake Danett K

    2012-02-01

    Full Text Available Abstract Background Alternative strategies are required to control the southern cattle tick, Rhipicephalus microplus, due to evolving resistance to commercially available acaricides. This invasive ectoparasite is a vector of economically important diseases of cattle such as bovine babesiosis and anaplasmosis. An understanding of the biological intricacies underlying vector-host-pathogen interactions is required to innovate sustainable tick management strategies that can ultimately mitigate the impact of animal and zoonotic tick-borne diseases. Tick saliva contains molecules evolved to impair host innate and adaptive immune responses, which facilitates blood feeding and pathogen transmission. Antigen presenting cells are central to the development of robust T cell responses including Th1 and Th2 determination. In this study we examined changes in co-stimulatory molecule expression and cytokine response of bovine macrophages exposed to salivary gland extracts (SGE obtained from 2-3 day fed, pathogen-free adult R. microplus. Methods Peripheral blood-derived macrophages were treated for 1 hr with 1, 5, or 10 μg/mL of SGE followed by 1, 6, 24 hr of 1 μg/mL of lipopolysaccharide (LPS. Real-time PCR and cytokine ELISA were used to measure changes in co-stimulatory molecule expression and cytokine response. Results Changes were observed in co-stimulatory molecule expression of bovine macrophages in response to R. microplus SGE exposure. After 6 hrs, CD86, but not CD80, was preferentially up-regulated on bovine macrophages when treated with 1 μg/ml SGE and then LPS, but not SGE alone. At 24 hrs CD80, CD86, and CD69 expression was increased with LPS, but was inhibited by the addition of SGE. SGE also inhibited LPS induced upregulation of TNFα, IFNγ and IL-12 cytokines, but did not alter IL-4 or CD40 mRNA expression. Conclusions Molecules from the salivary glands of adult R. microplus showed bimodal concentration-, and time-dependent effects on

  7. Acaricidal activity of synthesized titanium dioxide nanoparticles using Calotropis gigantea against Rhipicephalus microplus and Haemaphysalis bispinosa

    Institute of Scientific and Technical Information of China (English)

    Sampath; Marimuthu; Abdul; Abdul; Rahuman; Chidambaram; Jayaseelan; Arivarasan; Vishnu; Kirthi; Thirunavukkarasu; Santhoshkumar; Kanayairam; Velayutham; Asokan; Bagavan; Chinnaperumal; Kamaraj; Gandhi; Elango; Moorthy; Iyappan; Chinnadurai; Siva; Loganathan; Karthik; Kokati; Venkata; Bhaskara; Rao

    2013-01-01

    Objective:To assess the acaricidal activity of titanium dioxide nanoparticles(TiO2 NPs)synthesized from flower aqueous extract of Calotropis gigantea(C.gigantea)against the larvae of Rhipicephalus(Boophilus)microplus[R.(B.)microplus]and the adult of Haemaphrysalis bispinosa(H.bispinosa).Methods:The lyophilized C.gigantea flower aqueous extract of 50 mg was added with 100 mL of TiO(OH2)(10 mM)and magnetically stirred for 6 h.Synthesized TiO2 NPs were characterized by X-ray diffraction(XRD).Fourier transform infrared spectroscopy(FTIR),Scanning electron microscopy(SEM),and Energy dispersive X-ray spectroscopy(EDX).The synthesised TiO2 NPs were tested against the larvae of R(B.)microplus and adult of H.bispinosa were exposed to filter paper impregnated method.Results:XRD confirmed the crystalline nature of the nanoparticles with the mean size of 10.52 nm.The functional groups for synthesized TiO2NPs were 1405.19,and 1053.45 cm-1for-NH2 bending,primary amines and amides and 1053.84and 1078.45 cm-1for C-O.SEM micrographs of the synthesized TiO2 NPs showed the aggregated and spherical in shape.The maximum efficacy was observed in the aqueous flower extract of C.gigantea and synthesized TiO2 NPs against R.(B.)microplus(LC50=24.63 and 5.43 mg/L and r2=0.960 and 0.988)and against H.bispinosa(LC50=35.22 and 9.15 mg/L and r2=0.969 and 0.969).respectively.Conclusions:The synthesized TiO2 NPs were highly stable and had significant acaricidal activity against the larvae of R.(B.)microplus and adult of H.bispinosa.This study provides the first report of synthesized TiO2 NPs and possessed excellent anti-parasitic activity.

  8. Chemical composition and efficacy of dichloromethane extract of Croton sphaerogynus Baill. (Euphorbiaceae) against the cattle tick Rhipicephalus microplus (Acari: Ixodidae).

    Science.gov (United States)

    Righi, Adne A; Motta, Lucimar B; Klafke, Guilherme M; Pohl, Paula C; Furlan, Cláudia M; Santos, Deborah Y A C; Salatino, Maria L F; Negri, Giuseppina; Labruna, Marcelo B; Salatino, Antonio

    2013-02-18

    The cattle tick Rhipicephalus microplus is widely distributed in tropical and subtropical regions, causing high economic impact on cattle production. The control of tick infestations is regarded worldwide as critical and has been based on the use of organophosphates, synthetic pyretroids, amitraz and recently ivermectin and fipronil. The present study reports the analysis by gas chromatography/mass spectrometry of the constituents of leaf extracts of Croton sphaerogynus and results of acaricidal activity against the cattle tick R. microplus. The larval package test using the serial dilutions 0.625%, 1.25%, 2.5%, 5.0%, 10.0% and 20.0% (v/v) gave mortality rates 2.25%, 8.26%, 8.81%, 24.80%, 83.66% and 99.32%, respectively. Relevant constituents identified were abietanes, podocarpenes and clerodane type furano diterpenes. The present work may represent a possibility of attainment of natural substances useful for the control of R. microplus.

  9. HA03 as an Iranian Candidate Concealed Antigen for Vaccination against Hyalomma anatolicum anatolicum: Comparative Structural and In silico Studies

    OpenAIRE

    Mohammadi, A.; Aghaiypour, K; Keywanfar, H.; Paykari, H.,; Tajbakhsh, H.; Jalali, A.H.,; Safavieh, S.; Foroghi, A.

    2013-01-01

    In the last decades researchers had focused on developing a vaccine against tick based on protective antigen. Recombinant vaccines based on concealed antigen from Boophilus microplus have been developed in Australia and Cuba by the name of TICKGARD and GAVAC (De La Fuente and Kocan, 2006). Further studies on this antigen have shown some extent of protection against other species (De Vos et al., 2001). In Iran most important species is Hyalomma anatolicum and limited information about its cont...

  10. Gene expression profiling of adult female tissues in feeding Rhipicephalus microplus cattle ticks.

    Science.gov (United States)

    Stutzer, Christian; van Zyl, Willem A; Olivier, Nicholas A; Richards, Sabine; Maritz-Olivier, Christine

    2013-06-01

    The southern cattle tick, Rhipicephalus microplus, is an economically important pest, especially for resource-poor countries, both as a highly adaptive invasive species and prominent vector of disease. The increasing prevalence of resistance to chemical acaricides and variable efficacy of current tick vaccine candidates highlight the need for more effective control methods. In the absence of a fully annotated genome, the wealth of available expressed sequence tag sequence data for this species presents a unique opportunity to study the genes that are expressed in tissues involved in blood meal acquisition, digestion and reproduction during feeding. Utilising a custom oligonucleotide microarray designed from available singletons (BmiGI Version 2.1) and expressed sequence tag sequences of R. microplus, the expression profiles in feeding adult female midgut, salivary glands and ovarian tissues were compared. From 13,456 assembled transcripts, 588 genes expressed in all three tissues were identified from fed adult females 20 days post infestation. The greatest complement of genes relate to translation and protein turnover. Additionally, a number of unique transcripts were identified for each tissue that relate well to their respective physiological/biological function/role(s). These transcripts include secreted anti-hemostatics and defense proteins from the salivary glands for acquisition of a blood meal, proteases as well as enzymes and transporters for digestion and nutrient acquisition from ingested blood in the midgut, and finally proteins and associated factors involved in DNA replication and cell-cycle control for oogenesis in the ovaries. Comparative analyses of adult female tissues during feeding enabled the identification of a catalogue of transcripts that may be essential for successful feeding and reproduction in the cattle tick, R. microplus. Future studies will increase our understanding of basic tick biology, allowing the identification of shared proteins

  11. Acetylcholinesterase 1 in populations of organophosphate-resistant North American strains of the cattle tick, Rhipicephalus microplus (Acari: Ixodidae).

    Science.gov (United States)

    Bendele, Kylie G; Guerrero, Felix D; Miller, Robert J; Li, Andrew Y; Barrero, Roberto A; Moolhuijzen, Paula M; Black, Michael; McCooke, John K; Meyer, Jason; Hill, Catherine A; Bellgard, Matthew I

    2015-08-01

    Rhipicephalus microplus, the cattle fever tick, is a global economic problem to the cattle industry due to direct infestation of cattle and pathogens transmitted during feeding. Cattle fever tick outbreaks continue to occur along the Mexico-US border even though the tick has been eradicated from the USA. The organophosphate (OP) coumaphos targets acetylcholinesterase (AChE) and is the approved acaricide for eradicating cattle fever tick outbreaks. There is evidence for coumaphos resistance developing in cattle ticks in Mexico, and OP-resistant R. microplus ticks were discovered in outbreak populations of Texas in 2005. The molecular basis of coumaphos resistance is not known, and our study was established to gather further information on whether AChE1 is involved in the resistance mechanism. We also sought information on allele diversity in tick populations with different levels of coumaphos resistance. The overarching project goal was to define OP resistance-associated gene mutations such that a DNA-based diagnostic assay could be developed to assist the management of resistance. Three different AChE transcripts have been reported in R. microplus, and supporting genomic and transcriptomic data are available at CattleTickBase. Here, we report the complete R. microplus AChE1 gene ascertained by sequencing a bacterial artificial chromosome clone containing the entire coding region and the flanking 5' and 3' regions. We also report AChE1 sequences of larval ticks from R. microplus strains having different sensitivities to OP. To accomplish this, we sequenced a 669-bp region of the AChE1 gene corresponding to a 223 amino acid region of exon 2 to assess alleles in seven strains of R. microplus with varying OP resistance phenotypes. We identified 72 AChE1 sequence variants, 2 of which are strongly associated with OP-resistant phenotypes. Esterase-like sequences from the R. microplus transcriptome RmiTr Version 1.0 were compared to the available sequence databases to

  12. Prevalence of Resistant Strains of Rhipicephalus microplus to Acaricides in Cattle Ranch in the Tropical Region of Tecpan of Galeana, Guerrero, Mexico

    Directory of Open Access Journals (Sweden)

    J. Olivares-Pérez*, S. Rojas-Hernández, M.T. Valencia-Almazan, I. Gutiérrez-Segura and E.J. Míreles-Martínez

    2011-10-01

    Full Text Available Tick and tick borne diseases cause many problems to the cattle industry worldwide. The prevalence of resistant strains of Rhipicephalus microplus to different acaricides on cattle farms in the tropical region of Tecpan of Galeana, Guerrero, Mexico, and risk factors related to prevalence of resistant strains of R. microplus. Sixty one ranches infested were sampled; in each ranch were collected 30-50 fully-engorged female R. microplus ticks, of 10 cattle randomly selected, and evaluated in their progeny resistance to acaricides, using the larval packet test. The prevalence of resistant strains was total pyrethroids and amitraz. In organophosphorus 31.1, 48.3 and 82.2% of strains were resistant to clorpyriphos, coumaphos and diazinon, respectively. Risk factors favored (P<0.05 the development of resistant strains of acaricides. We concluded that the resistance of R. microplus to acaricides used to control a problem, and risk factors (livestock management have accelerated the development of resistance.

  13. Expression of immune response genes in peripheral blood of cattle infested with Rhipicephalus microplus.

    Science.gov (United States)

    Domingues, R; Wohlres-Viana, S; Reis, D R L; Teixeira, H C; Ferreira, A P; Guimarães, S E F; Prata, M C A; Furlong, J; Verneque, R S; Machado, M A

    2014-01-01

    The bovine tick Rhipicephalus microplus is responsible for severe economic losses in tropical cattle production. Bos indicus breeds are more resistant to tick infestations than are Bos taurus breeds, and the understanding of the physiological mechanisms involved in this difference is important for the development of new methods of parasite control. We evaluated differences in the transcript expression of genes related to the immune response in the peripheral blood of cattle previously characterized as resistant or susceptible to tick infestation. Crossbreed F2 Gir x Holstein animals (resistant, N = 6; susceptible, N = 6) were artificially submitted to tick infestation. Blood samples were collected at 0, 24, and 48 h after tick infestation and evaluated for transcript expression of the CD25, CXCL8, CXCL10, FoxP3, interleukin (IL)-10, and tumor necrosis factor alpha (TNFα) genes. Gene expression of CD25 (6.00, P resistant group at 48 h compared with samples collected before infestation. In the susceptible group, CXCL8 (-2.02, P resistance to R. microplus in cattle. PMID:24938612

  14. Evaluation of tea tree oil for controlling Rhipicephalus microplus in dairy cows.

    Science.gov (United States)

    Pazinatto Boito, Jhonatan; Santos, Roberto C; Vaucher, Rodrigo A; Raffin, Renata; Machado, Gustavo; Tonin, Alexandre A; Da Silva, Aleksandro S

    2016-07-30

    Our research aimed to test the effects of Melaleuca alternifolia oil (pure and in nanocapsules) in the control of Rhipicephalus microplus in dairy cattle. For this purpose, the in vivo studies used 15 cows distributed in three different groups with the same number of animals. Five cows remained untreated (Group A), representing the control group; other five cows were sprayed with TTO (at 5%) in its pure form (Group B); and five cows were sprayed with nanocapsules of TTO (at 0.75%) (Group C). On days 1 and 4 post-treatments (PT), all cows had their ticks counted. On day 1 PT, two ticks from each cow were collected to evaluate the effect of the treatment on ticḱs reproduction (in vitro assays). The pure form of TTO caused a significant reduction (P0.05). Treatment with TTO in nanocapsules (Group C) interfered with R. microplus reproduction, leading to lower oviposition by female ticks and hatchability (34.5% of efficacy). On the other hand, TTO oil (Group B) did not interfere on ticḱs reproduction, i.e. showed higher hatchability than the control group. Therefore, it is possible to conclude that pure TTO has an acaricidal effect in dairy cows, in addition to an effect on ticḱs reproduction when used its nanocapsulated form. PMID:27369577

  15. Biological parameters of two strains (acaricide resistant and susceptible of the tick Rhipicephalus microplusParâmetros biológicos de duas cepas (sensível e resistente a acaricidas do carrapato Rhipicephalus microplus

    Directory of Open Access Journals (Sweden)

    Luciana Dalla Rosa

    2013-10-01

    Full Text Available The resistance of Rhipicephalus microplus to acaricides occurs in almost all regions where it is present and treatments with chemicals are the most frequent. Therefore the monitoring of ticks is crucial to diagnose resistance at an early stage to help slow down the spread of resistance and to obtain knowledge of the distribution of acaricide resistance. The objective of the present work was to know the biological parameters of R. microplus sensitive strain to the main acaricides used. We compared the number and weight of engorged females, as well as the mass of eggs obtained the percentage of hatching and reproductive efficiency of two strains (acaricide-resistant and susceptible of the tick R. microplus, after passage in cattle. The results showed a reduced capacity to adjust the acaricide-susceptible strain, which presented the lowest number of ticks recovered (p?0.0001, with less weight and egg mass. With respect to reproductive parameters, the ticks susceptible strain showed hatching rate eggs (p=0.0002410 and reproductive efficiency reduced when compared with those of the acaricide-resistant strain. A resistência do Rhipicephalus microplus aos carrapaticidas ocorre em quase todas as regiões onde ele está presente e os tratamentos com produtos químicos são os mais frequentes. Portanto, monitoramento de carrapatos é fundamental para diagnosticar a resistência em um estágio inicial, diminuir a propagação e obter conhecimento da distribuição da resistência acaricida. Com o objetivo de se conhecer os parâmetros biológicos de uma cepa sensível de R. microplus aos principais carrapaticidas utilizados, o presente trabalho foi desenvolvido. Foram comparados o número e o peso de teleóginas, assim como a massa de ovos obtida, a percentagem de eclosão e a eficiência reprodutiva de duas cepas (sensível e resistente a acaricidas do carrapato R. microplus, após passagem em bovinos. Os resultados demonstraram uma menor capacidade de

  16. Injectable fipronil for cattle: Plasma disposition and efficacy against Rhipicephalus microplus.

    Science.gov (United States)

    Cid, Yara P; Ferreira, Thais P; Magalhães, Viviane S; Correia, Thais R; Scott, Fábio B

    2016-04-15

    Fipronil is a phenylpyrazole class insecticide. It is widely used as an insecticide in agriculture and in the control of ectoparasites in veterinary medicine. The application of fipronil in an injectable form (subcutaneously) becomes an innovation, since there is no commercially available preparation containing fipronil herein. The present study aimed at fipronil usage, applied subcutaneously in cattle, to control Rhipicephalus microplus. The assessing criteria used in the research have been the construction of the plasma concentration curve and efficacy studies. A method using High Performance Liquid Chromatograph with ultraviolet detection was developed for determination of fipronil in bovine plasma samples, providing a fast and simple process with good reproducibility and low limit of quantification. The validation of the analytical method showed linearity, selectivity, precision, accuracy, sensitivity and stability, thus proving it as suitable for routine analysis. This method showed to be an important investigative tool in the analysis of fipronil plasma concentration in cattle. Fipronil administered via subcutaneous in bovine reached the systemic circulation (Cmax=378.06±137.44 ng/mL), was quickly absorbed (t(max)=10±0.87 h), and its elimination occurred slowly (t(1/2)=12 days), while maintaining quantifiable blood plasma levels (23.79±12.16 ng/mL) for up to 21 days after the treatment with a 1 mg/kg dosage. The in vivo efficacy tests proved that fipronil applied subcutaneously in a single dose of 1 mg/kg in cattle exhibited a mean efficacy of 82.41% against R. microplus. The potential of subcutaneous injection as an alternative treatment route in cattle encourage the development of an injectable formulation of fipronil. PMID:26995714

  17. Injectable fipronil for cattle: Plasma disposition and efficacy against Rhipicephalus microplus.

    Science.gov (United States)

    Cid, Yara P; Ferreira, Thais P; Magalhães, Viviane S; Correia, Thais R; Scott, Fábio B

    2016-04-15

    Fipronil is a phenylpyrazole class insecticide. It is widely used as an insecticide in agriculture and in the control of ectoparasites in veterinary medicine. The application of fipronil in an injectable form (subcutaneously) becomes an innovation, since there is no commercially available preparation containing fipronil herein. The present study aimed at fipronil usage, applied subcutaneously in cattle, to control Rhipicephalus microplus. The assessing criteria used in the research have been the construction of the plasma concentration curve and efficacy studies. A method using High Performance Liquid Chromatograph with ultraviolet detection was developed for determination of fipronil in bovine plasma samples, providing a fast and simple process with good reproducibility and low limit of quantification. The validation of the analytical method showed linearity, selectivity, precision, accuracy, sensitivity and stability, thus proving it as suitable for routine analysis. This method showed to be an important investigative tool in the analysis of fipronil plasma concentration in cattle. Fipronil administered via subcutaneous in bovine reached the systemic circulation (Cmax=378.06±137.44 ng/mL), was quickly absorbed (t(max)=10±0.87 h), and its elimination occurred slowly (t(1/2)=12 days), while maintaining quantifiable blood plasma levels (23.79±12.16 ng/mL) for up to 21 days after the treatment with a 1 mg/kg dosage. The in vivo efficacy tests proved that fipronil applied subcutaneously in a single dose of 1 mg/kg in cattle exhibited a mean efficacy of 82.41% against R. microplus. The potential of subcutaneous injection as an alternative treatment route in cattle encourage the development of an injectable formulation of fipronil.

  18. Cytotoxic effects of extract of Acmella oleraceae (Jambú) in Rhipicephalus microplus females ticks.

    Science.gov (United States)

    de Oliveira, Patrícia Rosa; de Carvalho Castro, Karina Neoob; Anholeto, Luis Adriano; Camargo Mathias, Maria Izabel

    2016-08-01

    The present study analyzed the effects of different concentrations of the hexane extract of A. oleraceae (HEAO) (Jambú) on the germ cells of semi-engorged Rhipicephalus microplus female ticks, through a morpho-histological study, evaluating the effectiveness of the extract in the genesis of the individuals. To perform this analysis, 100 semi-engorged females were divided into five groups with 20 individuals each: groups I and II, respectively constituted by distilled water control and 50% ethanol + 1% DMSO, and groups III, IV, and V constituted by treatment with HEAO in the concentrations of 12.5, 25.0 and 50.0 mg/mL, respectively. All the ticks were immersed in the different concentrations of the extract or in distilled water for 5 minutes, dried and conditioned in BOD incubator for 7 days. The individuals of the treatment groups revealed the action of this extract showing alterations in the germ cells of the females from the different groups when compared with those from the groups I and II (control groups). These alterations were mainly related to the size and shape of the oocytes; number of yolk granules; presence, number, size and location of vacuoles in the cytoplasm of all the germ cells; and the presence of nuclear alterations in these cells as well. Thus, it was demonstrated that the concentrations of HEAO affected the germ cells of R. microplus ticks. The effects of the extract are similar to those caused by renowned and efficient chemical products used to control these ticks. Microsc. Res. Tech. 79:744-753, 2016. © 2016 Wiley Periodicals, Inc. PMID:27271726

  19. First report of pyrethroid resistance in Rhipicephalus (Boophilus) annulatus larvae (Say, 1821) from Iran.

    Science.gov (United States)

    Ziapour, Seyyed Payman; Kheiri, Sadegh; Asgarian, Fatemeh; Fazeli-Dinan, Mahmoud; Yazdi, Fariborz; Mohammadpour, Reza Ali; Aarabi, Mohsen; Enayati, Ahmadali

    2016-04-01

    Rhipicephalus (Boophilus) annulatus is one of the most important hard ticks parasitizing cattle in northern Iran. The aim of this study was to evaluate pyrethroid resistance levels of this species from Nur County, northern Iran. The hard ticks were collected through a multistage cluster randomized sampling method from the study area and fully engorged female R. (B.) annulatus were reared in a controlled insectary until they produced larvae for bioassay. Seventeen populations of the hard ticks were bioassayed with cypermethrin and 12 populations with lambda-cyhalothrin using a modified larval packet test (LPT). Biochemical assays to measure the contents/activity of different enzyme groups including mixed function oxidases (MFOs), glutathione S-transferases (GSTs) and general esterases were performed. Population 75 showed a resistance ratio of 4.05 with cypermethrin when compared with the most susceptible field population 66 at the LC50 level. With lambda-cyhalothrin the resistance ratio based on LC50 was 3.67 when compared with the susceptible population. The results of biochemical assays demonstrated significantly elevated levels of GSTs and esterases in populations tested compared with the heterozygous susceptible filed population and a correlation coefficient of these enzymes was found in association to lambda-cyhalothrin resistance. Based on the results, pyrethroid acaricides may operationally fail to control R. (B.) annulatus in North of Iran. This study is the first document of pyrethroid resistance in R. (B.) annulatus populations from Iran. PMID:26772446

  20. A model to simulate the effect of vaccination against Boophilus ticks on cattle.

    Science.gov (United States)

    Lodos, J; Boue, O; de la Fuente, J

    2000-02-01

    This paper describes a vaccination model to simulate the effect of cattle vaccination with concealed antigens on Boophilus tick spp. The model considers the vaccination effect in three parts: antibody titer, accumulation of damaging vaccination effects by parasite stages, and the effect of accumulated damage on all tick life stages. Biological parameters for ticks and hosts, as well as parameters describing tick-host interaction, were included. The validity of this model, integrated with the TICKSIM simulation program, was demonstrated for the Bm86-containing vaccine Gavac by comparing simulated and real data for several geographic locations in the Americas. All model parameters were estimated using field data collected in the different geographic locations. The model sensitivity to changes in antibody titer level and titer half-life was studied, and the impact on tick population density of changes in these parameters was evaluated. Simulation results showed that to achieve a higher level of tick control, an increase in the maximum antibody titer levels was more important than extending titer half-life in geographical locations with short seasonal peaks of tick infestation. The TICKSIM program, integrated with the new vaccination model, proved to be a framework for designing and evaluating tick control strategies, including vaccination with GavacTM. PMID:10669101

  1. Immunity against Boophilus annulatus induced by the Bm86 (Tick-GARD) vaccine.

    Science.gov (United States)

    Pipano, Eugene; Alekceev, Eugene; Galker, Felicia; Fish, Lea; Samish, Michael; Shkap, Varda

    2003-01-01

    Friesian cattle were immunized with two inoculations of anti-tick Bm86 (Tick-GARD) vaccine and were challenged 30 or 90 d later with Boophilus annulatus larvae derived from 1.2 g of eggs. No nymphs or adult ticks were found on the immunized cattle during four weeks after challenge. Repeated infestations (2 to 4) with larvae on three other calves during a period of 160 and 390 d after the immunization did not result in development of nymphal and adult stages. In control, non-immunized cattle infested with corresponding batches of larvae 1380 to 4653 replete adult female ticks were collected. Larvae issued from Babesia bovis-infected female ticks transmitted the infection to Bm86-immunized cattle, but the progeny of B. bigemina-infected females did not. Since B. bigemina is transmitted exclusively by nymphal stages of Bo. annulatus these results support the observation that immunity induced by Bm86 affects the larval stage of this tick. PMID:14580066

  2. First report of pyrethroid resistance in Rhipicephalus (Boophilus) annulatus larvae (Say, 1821) from Iran.

    Science.gov (United States)

    Ziapour, Seyyed Payman; Kheiri, Sadegh; Asgarian, Fatemeh; Fazeli-Dinan, Mahmoud; Yazdi, Fariborz; Mohammadpour, Reza Ali; Aarabi, Mohsen; Enayati, Ahmadali

    2016-04-01

    Rhipicephalus (Boophilus) annulatus is one of the most important hard ticks parasitizing cattle in northern Iran. The aim of this study was to evaluate pyrethroid resistance levels of this species from Nur County, northern Iran. The hard ticks were collected through a multistage cluster randomized sampling method from the study area and fully engorged female R. (B.) annulatus were reared in a controlled insectary until they produced larvae for bioassay. Seventeen populations of the hard ticks were bioassayed with cypermethrin and 12 populations with lambda-cyhalothrin using a modified larval packet test (LPT). Biochemical assays to measure the contents/activity of different enzyme groups including mixed function oxidases (MFOs), glutathione S-transferases (GSTs) and general esterases were performed. Population 75 showed a resistance ratio of 4.05 with cypermethrin when compared with the most susceptible field population 66 at the LC50 level. With lambda-cyhalothrin the resistance ratio based on LC50 was 3.67 when compared with the susceptible population. The results of biochemical assays demonstrated significantly elevated levels of GSTs and esterases in populations tested compared with the heterozygous susceptible filed population and a correlation coefficient of these enzymes was found in association to lambda-cyhalothrin resistance. Based on the results, pyrethroid acaricides may operationally fail to control R. (B.) annulatus in North of Iran. This study is the first document of pyrethroid resistance in R. (B.) annulatus populations from Iran.

  3. Mutation in the RmβAOR gene is associated with amitraz resistance in the cattle tick Rhipicephalus microplus

    OpenAIRE

    Sean W Corley; Jonsson, Nicholas N.; Piper, Emily K.; Cutullé, Christian; Stear, Michael J; Jennifer M. Seddon

    2013-01-01

    Amitraz is a widely used acaricide for the control of the cattle tick Rhipicephalus microplus, an important parasite of cattle in the tropics and subtropics. Here we describe in detail the evolution of amitraz resistance in replicated populations of ticks in the field, using divergent selection pressures with amitraz. We also demonstrate a close association between resistance to amitraz and a specific allele of the β-adrenergic octopamine receptor gene, which we propose confers resistance to ...

  4. 微小牛蜱Bm86基因的原核表达与表达条件的优化%Prokaryotic Expression of Bm86 Gene of Boophilus microplus and Optimization of the Expression Condition

    Institute of Scientific and Technical Information of China (English)

    马米玲; 关贵全; 李有全; 刘爱红; 任巧云; 牛庆丽; 殷宏; 罗建勋

    2009-01-01

    根据微小牛蜱Bin86基因序列设计引物,在重组质粒pMD18-T-Bin86中克隆,并将其定向亚克隆入原核表达载体pGEX-4T-1,转化至大肠埃希菌BL21(DE3)株,用不同浓度异丙基-β-D-硫代半乳糖苷(IPTG)在不同时间进行诱导表达.十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)检测结果表明,37℃条件下经1 mmol/L IPTG诱导8 h后,目的 重组蛋白表达量最大,表达相对分子质量(Mr)约为94000的包涵体蛋白,与预期大小一致,目的 蛋白约占蛋白总量的29%.蛋白质印迹(Western blotting)分析表明,该重组蛋白可被兔抗微小牛蜱全蜱阳性血清所识别.

  5. Cloning of Bm86 gene of Boophilus microplus and construction of recombinant expression vector%微小牛蜱Bm86基因的克隆及真核表达载体的构建

    Institute of Scientific and Technical Information of China (English)

    李文卉; 任巧云; 殷宏; 罗建勋; 刘磊; 党志胜; 高金亮; 关贵全; 刘志杰; 刘爱红; 马米玲

    2005-01-01

    为了克隆微小牛蜱Bm86基因及构建该基因的表达载体,以微小牛蜱饥饿幼蜱的破解物提取的总RNA为模板,参照已发表的微小牛蜱Bm86基因的核苷酸序列,设计了1对引物,采用 RT-PCR技术获得微小牛蜱Bm86基因;将Bm86基因克隆入载体,并进行序列分析,结果证明,克隆的Bm86基因序列与GenBank上登录的Bm86基因序列的同源性达97.4%,而且该序列包含完整的开放阅读框.将该基因克隆入真核表达载体pPIC9K,构建并获得了重组真核表达载体pPIC9K-Bm86.

  6. Cloning and expression of Bm86 gene of Boophilus microplus in E.coli%微小牛蜱Bm86基因的克隆与原核表达

    Institute of Scientific and Technical Information of China (English)

    樊瑞泉; 任巧云; 刘爱红; 罗建勋; 杨孝朴; 殷宏; 高金亮; 关贵全; 刘志杰; 党志胜; 马米玲

    2007-01-01

    根据已发表的Bm86基因序列,设计表达型引物,利用RT-PCR技术,从微小牛蜱饥饿幼蜱的研磨物中扩增Bm86基因,将PCR产物连入pGEM-T Easy载体,构建重组克隆载体pGEM-T easy-Bm86.测序分析表明:克隆的微小牛蜱Bm86基因序列与GenBank上登录的Bm86基因的核苷酸和氨基酸序列的同源性分别为97 %和95.6 %.然后对重组克隆载体pGEM-T easy-Bm86进行双酶切,获得带有粘性末端的Bm86基因片段,并将此片段定向亚克隆入原核表达载体pGEX-4T-1,构建重组原核表达载体pGEX-4T-1-Bm86,将其转化到BL21宿主菌中,用IPTG进行诱导表达.SDS-PAGE检测表明表达产物为分子量为88Ku的融合蛋白,目的蛋白约占蛋白总量的39 %,表达量约为1.08mg/mL.Western blot分析表明此表达产物能被兔抗微小牛蜱阳性血清所识别.

  7. Toxicity of neem seed oil against the larvae of Boophilus decoloratus, a one-host tick in cattle

    Directory of Open Access Journals (Sweden)

    Choudhury M

    2009-01-01

    Full Text Available The in vitro toxicity of neem seed oil (Azadirachta indica A. Juss, family: Meliaceae, Dogon yaro in Hausa language in Nigeria was tested against the larvae of a one-host tick, Boophilus decoloratus (family: Ixodidae or hard tick, commonly known as blue tick parasitic mainly to cattle generally found in savannas of tropical equatorial Africa. The 20, 40, 60, 80 and 100% concentrations of neem seed oil were found to kill all (100% mortality the larvae after 27, 27, 27, 27 and 24 h respectively.

  8. Toxicity of Neem Seed Oil against the Larvae of Boophilus decoloratus, A One-Host Tick In Cattle

    OpenAIRE

    Choudhury, M. K.

    2009-01-01

    The in vitro toxicity of neem seed oil (Azadirachta indica A. Juss, family: Meliaceae, Dogon yaro in Hausa language in Nigeria) was tested against the larvae of a one-host tick, Boophilus decoloratus (family: Ixodidae or hard tick, commonly known as blue tick) parasitic mainly to cattle generally found in savannas of tropical equatorial Africa. The 20, 40, 60, 80 and 100% concentrations of neem seed oil were found to kill all (100% mortality) the larvae after 27, 27, 27, 27 and 24 h respectiv...

  9. Toxicity of Neem Seed Oil against the Larvae of Boophilus decoloratus, A One-Host Tick In Cattle.

    Science.gov (United States)

    Choudhury, M K

    2009-09-01

    The in vitro toxicity of neem seed oil (Azadirachta indica A. Juss, family: Meliaceae, Dogon yaro in Hausa language in Nigeria) was tested against the larvae of a one-host tick, Boophilus decoloratus (family: Ixodidae or hard tick, commonly known as blue tick) parasitic mainly to cattle generally found in savannas of tropical equatorial Africa. The 20, 40, 60, 80 and 100% concentrations of neem seed oil were found to kill all (100% mortality) the larvae after 27, 27, 27, 27 and 24 h respectively. PMID:20502579

  10. Use of Ivermectin as Endoparasiticide in Tropical Cattle Herds Generates Resistance in Gastrointestinal Nematodes and the Tick Rhipicephalus microplus (Acari: Ixodidae).

    Science.gov (United States)

    Alegría-López, M A; Rodríguez-Vivas, R I; Torres-Acosta, J F J; Ojeda-Chi, M M; Rosado-Aguilar, J A

    2015-03-01

    The objective of the present study was to determine simultaneously the status of resistance against ivermectin (IVM) in gastrointestinal nematodes (GIN) and Rhipicephalus microplus (Canestrini, 1888) ticks in 12 cattle farms where IVM was used for the control of GIN in the Mexican tropics. Six farms had frequent use of IVM (≥ 4 times per year) and six farms had low frequency of IVM use (1-2 times per year). The fecal egg count reduction test and the larval immersion test were used to determine the resistant status of GIN and R. microplus against IVM, respectively. The results indicated that 100% of the surveyed farms had IVM-resistant GIN (reduction % from 0 to 67%). The genera involved were Haemonchus, Cooperia, Ostertagia, Trichostrongylus, and Oesophagostomum. Although the IVM was never used for the control of ticks, 50% of the surveyed farms presented GIN and R. microplus simultaneously resistant to IVM. Furthermore, two R. microplus populations showed high resistance ratio (RR) to IVM (farm TAT: RR50% = 7 and RR99% = 40.1; and farm SLS: RR50% = 2.4; RR99% = 11.0). A high frequency of IVM use (≥ 4 times per year) seemed to promote IVM resistance amongst R. microplus ticks compared with the farms with low frequency of IVM use (1-2 times per year; 66.6 vs. 25.0%, respectively). However, the number of surveyed farms was insufficient to show clear statistical inferences (odds ratio = 6.00; 95% CI = 0.341-105.5). The use of IVM for the control of GIN promoted simultaneously the development of IVM resistance in the GIN and R. microplus populations of the cattle herds surveyed. PMID:26336306

  11. Genetic diversity, acaricide resistance status and evolutionary potential of a Rhipicephalus microplus population from a disease-controlled cattle farming area in South Africa.

    Science.gov (United States)

    Robbertse, Luïse; Baron, Samantha; van der Merwe, Nicolaas A; Madder, Maxime; Stoltsz, Wilhelm H; Maritz-Olivier, Christine

    2016-06-01

    The Southern cattle tick, Rhipicephalus microplus is a hematophagous ectoparasite of great veterinary and economic importance. Along with its adaptability, reproductive success and vectoring capacity, R. microplus has been reported to develop resistance to the major chemical classes of acaricides currently in use. In South Africa, the Mnisi community in the Mpumalanga region offers a unique opportunity to study the adaptive potential of R. microplus. The aims of this study therefore included characterising acaricide resistance and determining the level and pattern of genetic diversity for R. microplus in this region from one primary population consisting of 12 communal dip-stations. The level of acaricide resistance was evaluated using single nucleotide polymorphisms (SNPs) in genes that contribute to acaricide insensitivity. Additionally, the ribosomal internal transcribed spacer 2 (ITS2) gene fragments of collected individuals were sequenced and a haplotype network was constructed. A high prevalence of alleles attributed to resistance against formamidines (amitraz) in the octopamine/tyramine (OCT/Tyr) receptor (frequency of 0.55) and pyrethroids in the carboxylesterase (frequency of 0.81) genes were observed. Overall, the sampled tick population was homozygous resistant to pyrethroid-based acaricides in the voltage-gated sodium channel (VGS) gene. A total of 11 haplotypes were identified in the Mnisi R. microplus population from ITS2 analysis with no clear population structure. From these allele frequencies it appears that formamidine resistance in the Mnisi community is on the rise, as the R. microplus populations is acquiring or generating these resistance alleles. Apart from rearing multi-resistant ticks to commonly used acaricides in this community these ticks may pose future problems to its surrounding areas. PMID:26965787

  12. Genetic diversity, acaricide resistance status and evolutionary potential of a Rhipicephalus microplus population from a disease-controlled cattle farming area in South Africa.

    Science.gov (United States)

    Robbertse, Luïse; Baron, Samantha; van der Merwe, Nicolaas A; Madder, Maxime; Stoltsz, Wilhelm H; Maritz-Olivier, Christine

    2016-06-01

    The Southern cattle tick, Rhipicephalus microplus is a hematophagous ectoparasite of great veterinary and economic importance. Along with its adaptability, reproductive success and vectoring capacity, R. microplus has been reported to develop resistance to the major chemical classes of acaricides currently in use. In South Africa, the Mnisi community in the Mpumalanga region offers a unique opportunity to study the adaptive potential of R. microplus. The aims of this study therefore included characterising acaricide resistance and determining the level and pattern of genetic diversity for R. microplus in this region from one primary population consisting of 12 communal dip-stations. The level of acaricide resistance was evaluated using single nucleotide polymorphisms (SNPs) in genes that contribute to acaricide insensitivity. Additionally, the ribosomal internal transcribed spacer 2 (ITS2) gene fragments of collected individuals were sequenced and a haplotype network was constructed. A high prevalence of alleles attributed to resistance against formamidines (amitraz) in the octopamine/tyramine (OCT/Tyr) receptor (frequency of 0.55) and pyrethroids in the carboxylesterase (frequency of 0.81) genes were observed. Overall, the sampled tick population was homozygous resistant to pyrethroid-based acaricides in the voltage-gated sodium channel (VGS) gene. A total of 11 haplotypes were identified in the Mnisi R. microplus population from ITS2 analysis with no clear population structure. From these allele frequencies it appears that formamidine resistance in the Mnisi community is on the rise, as the R. microplus populations is acquiring or generating these resistance alleles. Apart from rearing multi-resistant ticks to commonly used acaricides in this community these ticks may pose future problems to its surrounding areas.

  13. Acaricide and ivermectin resistance in a field population of Rhipicephalus microplus (Acari: Ixodidae) collected from red deer (Cervus elaphus) in the Mexican tropics.

    Science.gov (United States)

    Rodríguez-Vivas, R I; Miller, R J; Ojeda-Chi, M M; Rosado-Aguilar, J A; Trinidad-Martínez, I C; Pérez de León, A A

    2014-02-24

    In the Neotropics the control of tick infestations in red deer (Cervus elaphus) is achieved primarily through the use of acaricides and macrocyclic lactones. In Mexico, resistance to one or multiple classes of acaricides has been reported in Rhipicephalus microplus infesting cattle, but information on acaricide susceptibility in R. microplus infesting red deer is lacking. In this study we report the level of resistance to different classes of acaricides and ivermectin in R. microplus collected from red deer in the Mexican tropics. Engorged R. microplus females were collected from a red deer farm in Yucatan, Mexico. The larval packet test was used to detect resistance to the organophosphates (OPs) chlorpyrifos and coumaphos, synthetic pyrethroids (SPs) cypermethrin and permethrin, and the phenylpyrazol, fipronil. Resistance to the formamidine amitraz (Am), and ivermectin was ascertained using the larval immersion test. Data were subjected to probit analysis to determine lethal concentrations and resistance ratios to kill 50% (RR50) and 99% (RR99) of the tick population under evaluation in relation to susceptible reference strains. Additionally, allele specific polymerase chain reaction was used to detect the sodium channel F1550I mutation associated with SP resistance in R. microplus. The R. microplus population from red deer in Yucatan showed very high resistance to the two SPs evaluated (RRs>72.2 for cypermethrin; RR for permethrin resistance was so high a dose-response curve was not possible). All individual larvae tested to detect the sodium channel F1550I mutation associated with SP resistance in R. microplus were homozygous. The same tick population showed different levels of resistance to OPs (chlorpyrifos: RR50=1.55, RR99=0.63; coumaphos: RR50=6.8, RR99=5.9), fipronil (RR50=1.8, RR99=0.9), and amitraz (RR50=2.3, RR99=4.4). Resistance to ivermectin was regarded as moderate (RR50=7.1, RR99=5.0). This is the first report of R. microplus ticks collected from red

  14. EFICACIA DE LA MEZCLA DE DOS CEPAS DE Metarhizium anisopliae (Deuteromycotina: Hyphomycetes) PARA EL CONTROL DE Rhipicephalus microplus EN INFESTACIONES NATURALES EN BOVINOS

    OpenAIRE

    Uriel Jesús Rodríguez-Alcocer; Roger Iván Rodríguez-Vivas; Melina Maribel Ojeda-Chi; Edelmira Galindo-Velasco; Roberto Lezama-Gutiérrez

    2014-01-01

    El objetivo del presente estudio fue evaluar la eficacia de Metarhizium anisopliae para el control de Rhipicephalus microplus en ganado bovino infestado naturalmente. El estudio se realizó en una unidad de producción de ganado bovino ubicada en el trópico Mexicano. Se formaron dos grupos de 10 bovinos basado en el número de garrapatas R. microplus adultas y fases juveniles (larvas y ninfas). Los animales del grupo tratado (promedio de 73.4 y 27.5 garrapatas adultas y juveniles respectivamente...

  15. Control de Rhipicephalus microplus (Acari: Ixodidae) mediante el uso del hongo entomopatógeno Metarhizium anisopliae (Hypocreales: Clavicipitaceae). Revisión

    OpenAIRE

    Melina Maribel Ojeda-Chi; Roger Ivan Rodríguez-Vivas; Edelmira Galindo-Velasco; Roberto Lezama-Gutiérrez; Carlos Cruz-Vázquez

    2011-01-01

    Las infestaciones de la garrapata del ganado, Rhipicephalus microplus, producen el mayor problema global de ectoparásitos en ganado de regiones tropicales y subtropicales, provocan importantes pérdidas económicas en la producción de carne, leche y pieles, además incrementan los gastos derivados de los programas de control, y son capaces de transmitir Babesia bovis, B. bigemina y Anaplasma marginale. El control de R. microplus se basa principalmente en el uso de ixodicidas, sin embargo, su uso...

  16. Host resistance in cattle to infestation with the cattle tick Rhipicephalus microplus.

    Science.gov (United States)

    Jonsson, N N; Piper, E K; Constantinoiu, C C

    2014-11-01

    Resistance to Rhipicephalus microplus infestation in cattle has many effector mechanisms, each of which is likely to be modulated by complex, interacting factors. Some of the mechanisms of host resistance and their modulating factors have been identified and quantified, although much remains to be explained. The variation in resistance to tick infestation is most marked between Bos taurus and Bos indicus cattle, taurine cattle given the same exposure carrying between five and 10 times as many ticks as indicine cattle. Tick resistance is mostly manifest against attaching larvae, which attempt to feed often and without success, death occurring mostly within 24 h of finding a host. There is evidence of innate and adaptive immune response to tick infestation, and it appears that the relative importance of each differs between indicine and taurine cattle. There is conflicting information regarding the role of humoral immunity in tick resistance, and recent studies indicate that strong IgG responses to tick antigens are not protective. A strong T-cell-mediated response directed against larval stages, as mounted by indicine cattle, seems to be protective. Variation in the extracellular matrix of skin (epidermal growth factors, collagens and other matrix components such as lumican) also contributes to variation in host resistance. PMID:25313455

  17. Non-Classical Gluconeogenesis-Dependent Glucose Metabolism in Rhipicephalus microplus Embryonic Cell Line BME26

    Directory of Open Access Journals (Sweden)

    Renato Martins da Silva

    2015-01-01

    Full Text Available In this work we evaluated several genes involved in gluconeogenesis, glycolysis and glycogen metabolism, the major pathways for carbohydrate catabolism and anabolism, in the BME26 Rhipicephalus microplus embryonic cell line. Genetic and catalytic control of the genes and enzymes associated with these pathways are modulated by alterations in energy resource availability (primarily glucose. BME26 cells in media were investigated using three different glucose concentrations, and changes in the transcription levels of target genes in response to carbohydrate utilization were assessed. The results indicate that several genes, such as glycogen synthase (GS, glycogen synthase kinase 3 (GSK3, phosphoenolpyruvate carboxykinase (PEPCK, and glucose-6 phosphatase (GP displayed mutual regulation in response to glucose treatment. Surprisingly, the transcription of gluconeogenic enzymes was found to increase alongside that of glycolytic enzymes, especially pyruvate kinase, with high glucose treatment. In addition, RNAi data from this study revealed that the transcription of gluconeogenic genes in BME26 cells is controlled by GSK-3. Collectively, these results improve our understanding of how glucose metabolism is regulated at the genetic level in tick cells.

  18. High resolution predictive mapping of Rhipicephalus microplus and R. annulatus in south Texas after vaccination with the anti-tick vaccine Gavac

    Science.gov (United States)

    Conventional anti-tick vaccines based on the tick gut antigen Bm86 exist commercially (TickGARD and Gavac) and could serve as an alternative to the use of acaricides to eradicate ticks, but their level of efficacy against R. microplus is too low for eradication if used alone. Therefore, the current ...

  19. Influence of grooming on Rhipicephalus microplus tick infestation and serum cortisol rates

    Directory of Open Access Journals (Sweden)

    Fernanda Ferreira Pessoa

    2012-12-01

    Full Text Available Grooming is an important factor on animal resistance to ticks. Rhipicephalus microplus is the most pathogenic cattle tick in Brazil causing death in susceptible animals. Cortisol is the hormone of stress. The influence of grooming on tick infestation and serum cortisol level was studied in 16 Holstein heifers from fifth to eight-month-old. They were infested with 10,000 larvae in June/20/2011. Half of them used a necklace made of wood strips and had an infestation chamber made by cotton cloth covering about 50 cm diameter of the shaved flank, fixed at the skin in both sides with adhesive to prevent larvae to escape from the infestation chamber and the amount of larvae was divided into the two chambers. Such artifacts had the purpose to avoid grooming. The heifers remained all the tick parasitic life cycle in individual pens inside a closed shed at Instituto de Zootecnia, in Nova Odessa, São Paulo State. Tick females bigger than 4.5 mm were counted in the right side from day 20 to 22 after the artificial infestation. The tick recovery rate was calculated by adding and multiplying by two the number of ticks counted, assuming that 5,000 female larvae had infested the cattle. Immediately before infestation (day 0 and in day2, day8, and day17 after infestation, blood samples were collected using vacuum tubes, in the morning (8:30 – 10:00 A.M.. Cortisol was measured by immunoassay (EIA and the D.O. (optical density at 420 nm was converted in ng of cortisol/mL of serum sample. The experimental design was randomized with 8 replications. Data from serum cortisol were analyzed using the General linear models of the SPSS® statistical package (version 12.0 using the presence of the artifacts (necklace and chamber and sampling day as independent variables and serum cortisol as the dependent variable. In the analyse of tick recovery rate, the presence of artifacts was the independent variable and tick recovery rate the dependent variable. The presence of

  20. Mutation in the RmβAOR gene is associated with amitraz resistance in the cattle tick Rhipicephalus microplus.

    Science.gov (United States)

    Corley, Sean W; Jonsson, Nicholas N; Piper, Emily K; Cutullé, Christian; Stear, Michael J; Seddon, Jennifer M

    2013-10-15

    We aimed to describe the evolution of resistance to amitraz in Rhipicephalus microplus in the field and to test the association between amitraz resistance and the frequency of a mutation in the β-adrenergic octopamine receptor gene (RmβAOR). We established six populations of Rhipicephalus microplus ticks in similar paddocks by the admixture of ticks from strains known to be susceptible and resistant to amitraz and synthetic pyrethroids. Each population was managed using one of three acaricide treatment regimes: always amitraz, always spinosad, or rotation between amitraz and spinosad. We used microsatellites to elucidate population structure over time, an SNP in the para-sodium channel gene previously demonstrated to confer resistance to synthetic pyrethroids to quantify changes in resistance to synthetic pyrethroids over time, and a nonsynonymous SNP in the RmβAOR, a gene that we proposed to confer resistance to amitraz, to determine whether selection with amitraz increased the frequency of this mutation. The study showed panmixia of the two strains and that selection of ticks with amitraz increased the frequency of the RmβAOR mutation while increasing the prevalence of amitraz-resistance. We conclude that polymorphisms in the RmβAOR gene are likely to confer resistance to amitraz. PMID:24082133

  1. In Vitro Evaluation of Ethanolic Extracts of Ageratum conyzoides and Artemisia absinthium against Cattle Tick, Rhipicephalus microplus

    Directory of Open Access Journals (Sweden)

    S. Parveen

    2014-01-01

    Full Text Available In vitro efficacy of ethanolic extracts obtained from the aerial parts of Ageratum conyzoides and Artemisia absinthium was assessed on Rhipicephalus microplus using adult immersion test (AIT. Five concentrations of the extract (1.25%, 2.5%, 5%, 10%, and 20% with three replications for each concentration were used in the bioassay. In AIT, the maximum mortality was recorded as 40% and 66.7% at 20% concentration for A. conyzoides and A. absinthium, respectively. Acaricidal activity was found to be higher in the extract of A. absinthium with LC50 and LC95 values of 11.2% and 61.7%, respectively. Egg mass weight of the live ticks treated with different concentrations of the extracts was significantly (P<0.05 lower than that of control ticks; consequently, the reproductive index and oviposition values of the treated ticks were reduced significantly (P<0.05. The A. conyzoides inhibited 90% hatching of eggs at the 20% concentration, whereas A. absinthium showed 100% inhibition at 5%, 10%, and 20% concentrations. The results show that A. absinthium has better acaricidal properties than A. conyzoides and could be useful in controlling R. microplus.

  2. Characterisation of divergent flavivirus NS3 and NS5 protein sequences detected in Rhipicephalus microplus ticks from Brazil

    Directory of Open Access Journals (Sweden)

    Sandra Regina Maruyama

    2014-02-01

    Full Text Available Transcripts similar to those that encode the nonstructural (NS proteins NS3 and NS5 from flaviviruses were found in a salivary gland (SG complementary DNA (cDNA library from the cattle tick Rhipicephalus microplus. Tick extracts were cultured with cells to enable the isolation of viruses capable of replicating in cultured invertebrate and vertebrate cells. Deep sequencing of the viral RNA isolated from culture supernatants provided the complete coding sequences for the NS3 and NS5 proteins and their molecular characterisation confirmed similarity with the NS3 and NS5 sequences from other flaviviruses. Despite this similarity, phylogenetic analyses revealed that this potentially novel virus may be a highly divergent member of the genus Flavivirus. Interestingly, we detected the divergent NS3 and NS5 sequences in ticks collected from several dairy farms widely distributed throughout three regions of Brazil. This is the first report of flavivirus-like transcripts in R. microplus ticks. This novel virus is a potential arbovirus because it replicated in arthropod and mammalian cells; furthermore, it was detected in a cDNA library from tick SGs and therefore may be present in tick saliva. It is important to determine whether and by what means this potential virus is transmissible and to monitor the virus as a potential emerging tick-borne zoonotic pathogen.

  3. Toxicity of neem seed oil against the larvae of Boophilus decoloratus, a one-host tick in cattle

    OpenAIRE

    Choudhury M

    2009-01-01

    The in vitro toxicity of neem seed oil (Azadirachta indica A. Juss, family: Meliaceae, Dogon yaro in Hausa language in Nigeria) was tested against the larvae of a one-host tick, Boophilus decoloratus (family: Ixodidae or hard tick, commonly known as blue tick) parasitic mainly to cattle generally found in savannas of tropical equatorial Africa. The 20, 40, 60, 80 and 100% concentrations of neem seed oil were found to kill all (100% mortality) the larvae after 27, 27, 27, 27 and ...

  4. The First Report of Rhipicephalus (Boophilus kohlsi (Hoogstraal and Kaiser 1960 from Wild Goats (Capra hircus aega¬grus in Iran

    Directory of Open Access Journals (Sweden)

    S Nabian

    2007-05-01

    Full Text Available Background: Studies concerning ticks were of interest to evaluate the distribution and composition of species affecting live¬stock, thus it was a main step in our knowledge of the pathogens that they may transmit by tick. Methods: A collection of 21 adult female and 15 male hard ticks, all is representing a single species of tick collected under the tail of wild goat. The specimens preserved in 70 % alcohol in glass vial and brought to laboratory for identification. In or¬der to distinguish species relationships between wild and domestic animals, tick sampling has been achieved in 7 different places located around Kolah Qazi national park in Isfahan Province. Results: Important descriptions of ticks isolated from wild goat strongly supported that the tick species in this collection was only Rhipicephalus (Boophilus kohlsi. Conclusion: It seems that this is the first report of Rh. (Boophilus kohlsi in Iran. Wild sheep and goats live throughout Iran ex¬cept in forest and other tall vegetation areas. Although, both animals has pastured occasionally in same open rangeland but we could not find any tick of Rh. (Boophilus kohlsi in domestic animals.

  5. Dicty_cDB: Contig-U01650-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 8.g Rhipicephalus (boophilus) microplus B... 34 2.0 3 ( FG285891 ) 1108770704094 New World Screwworm Egg 926...nosize Bicyclus anynan... 30 2.6 4 ( FG294764 ) 1108770717863 New World Screwworm

  6. Rhipicephalus microplus lipocalins (LRMs): genomic identification and analysis of the bovine immune response using in silico predicted B and T cell epitopes.

    Science.gov (United States)

    Rodriguez-Valle, Manuel; Moolhuijzen, Paula; Piper, Emily K; Weiss, Olivia; Vance, Megan; Bellgard, Matthew; Lew-Tabor, Ala

    2013-08-01

    The attachment to host skin by Rhipicephalus microplus larvae induces a series of physiological events at the attachment site. The host-parasite interaction might induce a rejection of the larvae, as is frequently observed in Bos taurus indicus cattle, and under certain conditions in Bos taurus taurus cattle. Ticks deactivate the host rejection response by secreting specific proteins and lipids that play an essential role in manipulation of the host immune response. The available genomic information on the R. microplus tick was mined using bioinformatics approaches to identify R. microplus lipocalins (LRMs). This in silico examination revealed a total of 12 different putative R. microplus LRMs (LRM1-LRM12). The identity of the LRM family showed high sequence variability: from 6% between LRM7 and LRM8 to 55.9% between LRM2 and LRM6. However, the three-dimensional structure of the lipocalin family was conserved in the LRMs. The B and T cell epitopes in these lipocalins were then predicted, and six of the LRMs (5, 6, 9, 10, 11 and 12) were used to examine the host immune interactions with sera and peripheral blood mononuclear cells (PBMCs) collected from tick-susceptible and tick-resistant cattle challenged with R. microplus. On days 28-60 after tick infestation, the anti-LRM titres were higher in the resistant group compared with the susceptible cattle. After 60 day, the anti-LRM titres (except LRM9 and LRM11) decreased to zero in the sera of both the tick-resistant and tick-susceptible cattle. Using cell proliferation assays, the PBMCs challenged with some of the predicted T cell epitopes (LRM1_T1, T2; LRM_T1, T2 and LRM12_T) exhibited a significantly higher number of IFN-γ-secreting cells (Th1) in tick-susceptible Holstein-Friesians compared with tick-resistant Brahman cattle. In contrast, expression of the Th2 cytokine (IL-4) was lower in Holstein-Friesians cattle compared with Brahman cattle. Moreover, this study found that LRM6, LRM9 and LRM11 play important

  7. Filiform papilla of holstein’s tongue and its relation with the Rhipicephalus microplus tick resistance

    Directory of Open Access Journals (Sweden)

    Cecília José Veríssimo

    2012-12-01

    Full Text Available Several studies describe anatomical, morphological and histological analysis of domestic and wild animals tongue. The tongue is an extendable muscular organ that performs gripping, chewing, and swallowing food actions and executes tasting and mechanical body self-cleaning functions (grooming. The distribution of these tongue characteristics may vary, according to different species, but studies made with different animals classes reveal the filiform papilla acting in mechanical body cleaning function. In order to evaluate these mechanical functions, especially the self-cleaning one, we proposed to investigate filiform papillae length or its base dimensions would be related to the heifers resistance to Rhipicephalus microplus tick. Biopsies were performed in eight (8 Holstein heifers’ tongues, with a 6 mm diameter punch, in the anterior third of tongues, at the distance of 3 cm from its tip. The animals were anesthetized with xylazine hydrochloride 2%, a sedative, analgesic and muscle relaxant and received local anesthetic, hydrochloride 2.0 g lidocaine. After tissue removal, the local lesions received an ointment of triamcinolone acetonide, 1.0 mg g-1. The Holstein heifers were one year and half old and naturally infested with ticks in a paddock situated at “Instituto de Zootecnia”. We monitored their natural infestation by counting females ticks, greater than 4.5 mm, presents in every animal, in four weekly evaluations (from 8 to 28 December – 2011. These samples were submitted to technical process of fixation and dehydration (as required by in the scanning electron microscope study, in the laboratory NAP/MEPA - ESALQ-USP. The papillae were visualized and measured with the aid of the measurement tool between two points of the software in the scanning electron microscope Zeiss LEO 435VP. Statistically analyses were performed by the SPSSP 12.0 program in a complete randomized design. We employed the Oneway method for variance analysis to

  8. Efectos garrapaticidas de algunos aceites esenciales

    OpenAIRE

    Juan F. Gil; Burillo Alquézar, Jesús; Pastor, Ana; Ringuelet, Jorge; Elder, Heriberto; Echeverri, Fernando

    2013-01-01

    Soluciones acuo-etanólicas de aceites esenciales de Lippia (3 quimiotipos), Schinus molle, Tagetes, Lavandina (dos quimiotipos), Hisopo, Romero y Ciprés, fueron sometidas a ensayos in Vitro para evaluar sus efectos sobre le supervivencia y reproducción de las garrapata Rhipicephalus (Boophilus) microplus. Los aceites de Lippia, Tagetes e Hisopo mostraron buenos niveles de inhibición de la oviposición y de mortalidad superiores al 50%, a una concentración del 1%; no obstante, a concentracio...

  9. First report of fluazuron resistance in Rhipicephalus microplus: a field tick population resistant to six classes of acaricides.

    Science.gov (United States)

    Reck, José; Klafke, Guilherme Marcondes; Webster, Anelise; Dall'Agnol, Bruno; Scheffer, Ramon; Souza, Ugo Araújo; Corassini, Vivian Bamberg; Vargas, Rafael; dos Santos, Julsan Silveira; Martins, João Ricardo de Souza

    2014-03-17

    The control of the cattle tick Rhipicephalus microplus is based mainly on the use of chemical acaricides, which has contributed to the emerging problem of selection of resistant tick populations. Currently, there are six main classes of acaricides commercially available in Brazil to control cattle ticks, with fluazuron, a tick growth regulator with acaricidal properties, being the only active ingredient with no previous reports of resistance. Ticks (designated the Jaguar strain) were collected in a beef cattle ranch located at Rio Grande do Sul state, Southern Brazil, after a complaint of fluazuron treatment failure. To characterise the resistance of this strain against acaricides, larval tests were performed and showed that the Jaguar strain was resistant to all of the drugs tested: cypermethrin (resistance ratio, RR=31.242), chlorpyriphos (RR=103.926), fipronil (RR=4.441), amitraz (RR=11.907) and ivermectin (3.081). A field trial was conducted to evaluate the efficacy of fluazuron treatment in heifers that had been experimentally infested with the Jaguar or a susceptible strain. Between 14 and 28 days after treatment, the average efficacy in cattle experimentally infested with the susceptible strain was 96%, while for the Jaguar strain the efficacy was zero. Additionally, the Jaguar strain response to fluazuron was evaluated in vitro using a modified adult immersion test (AIT) and the artificial feeding assay (AFA). With the AIT, 50 ppm of fluazuron inhibited 99% of larvae hatching in the susceptible strain (POA) and less than 50% in the Jaguar strain. Results of the AFA showed a larval hatching rate of 67% at 2.5 ppm of fluazuron with the Jaguar strain; conversely, only 3% of larvae of the susceptible strain hatched at the same fluazuron concentration. The results showed here demonstrated the first case of fluazuron resistance in R. microplus and the first tick population resistant to six classes of acaricides in Brazil. PMID:24560364

  10. Evaluation of the Efficacy of Acaricides Used to Control the Cattle Tick, Rhipicephalus microplus, in Dairy Herds Raised in the Brazilian Southwestern Amazon.

    Science.gov (United States)

    Brito, Luciana G; Barbieri, Fábio S; Rocha, Rodrigo B; Oliveira, Márcia C S; Ribeiro, Elisana Sales

    2011-01-01

    The adult immersion test (AIT) was used to evaluate the efficacy of acaricide molecules used for control of Rhipicephalus microplus on 106 populations collected in five municipalities in the state of Rondônia in the Brazilian South Occidental Amazon region. The analysis of the data showed that the acaricide formulations had different efficacies on the tick populations surveyed. The synthetic pyrethroids (SPs) acaricides were the least effective (48.35-76.84%), followed by SP + organophosphate (OP) associations (68.91-81.47%) and amidine (51.35-100%). For the macrocyclic lactones (MLs), the milbemycin (94.84-100%) was the most effective, followed by spinosad (93.21-100%) and the avermectins (81.34-100%). The phenylpyrazole (PZ) group had similar efficacy (99.90%) to the MLs. Therefore, SP acaricides, including associations with OP, and formulations based on amidine presented low in vitro efficacy to control the R. microplus populations surveyed. PMID:21547224

  11. Assessment of the acaricidal activity of carvacrol, (E)-cinnamaldehyde, trans-anethole, and linalool on larvae of Rhipicephalus microplus and Dermacentor nitens (Acari: Ixodidae).

    Science.gov (United States)

    de Oliveira Souza Senra, Tatiane; Zeringóta, Viviane; de Oliveira Monteiro, Caio Márcio; Calmon, Fernanda; Maturano, Ralph; Gomes, Geovany Amorim; Faza, Aline; de Carvalho, Mario Geraldo; Daemon, Erik

    2013-04-01

    The acaricidal activity of carvacrol, (E)-cinnamaldehyde, trans-anethole, and linalool was studied on Rhipicephalus microplus and Dermacentor nitens larvae. All the substances were tested at concentrations of 2.5, 5.0, 10.0, 15.0, and 20.0 μl/ml, with 10 repetitions per treatment. The modified larval packet technique was employed in the tests and the mortality was evaluated after 24 h. In the groups treated with carvacrol, the lowest concentration (2.5 μl/ml) was sufficient to cause 100% death of the R. microplus and D. nitens larvae. The same concentration of (E)-cinnamaldehyde resulted in death of approximately 99% of the larvae of both tick species and reached 100% at the other concentrations. For trans-anethole, mortality rates above 90% of the R. microplus and D. nitens larvae were only observed starting at the concentration of 15.0 μl/ml and reached 100% at the highest concentration (20.0 μl/ml). Finally, the mortality rates of the groups treated with linalool were low, only reaching 8.4 and 14.5% at the highest concentration (20.0 μl/ml) for larvae of D. nitens and R. microplus, respectively. These results show that carvacrol, (E)-cinnamaldehyde, and trans-anethole have acaricidal activity, particularly carvacrol and (E)-cinnamaldehyde, both of which resulted in high mortality rates for the larvae of these two tick species even at the lowest concentration.

  12. Evaluation of the Efficacy of Acaricides Used to Control the Cattle Tick, Rhipicephalus microplus, in Dairy Herds Raised in the Brazilian Southwestern Amazon

    OpenAIRE

    Luciana G. Brito; Barbieri, Fábio S.; Rocha, Rodrigo B.; Márcia C. S. Oliveira; Ribeiro, Elisana Sales

    2011-01-01

    The adult immersion test (AIT) was used to evaluate the efficacy of acaricide molecules used for control of Rhipicephalus microplus on 106 populations collected in five municipalities in the state of Rondônia in the Brazilian South Occidental Amazon region. The analysis of the data showed that the acaricide formulations had different efficacies on the tick populations surveyed. The synthetic pyrethroids (SPs) acaricides were the least effective (48.35–76.84%), followed by SP + organophosphate...

  13. Acaricidal activity of the organic extracts of thirteen South African plants against Rhipicephalus (Boophilus) decoloratus (Acari: Ixodidae).

    Science.gov (United States)

    Fouche, Gerda; Ramafuthula, Mary; Maselela, Vusi; Mokoena, Moses; Senabe, Jeremiah; Leboho, Tlabo; Sakong, Bellonah M; Adenubi, Olubukola T; Eloff, Jacobus N; Wellington, Kevin W

    2016-07-15

    The African blue tick, Rhipicephalus (Boophilus) decoloratus, is a common tick species found in South Africa and affects cattle production as well as vectoring pathogens in regions of Africa and Asia. In an attempt to develop a non-toxic, lower cost and environmentally friendly tick control method, twenty-six plant extracts were prepared from thirteen plant species using 99.5% acetone and 99% ethanol. The adapted Shaw Larval Immersion Test (SLIT) was used to test the efficacy of the extracts. A 1% solution of each of the plant extracts was prepared for efficacy testing and the ethanol extracts were found to have better acaricidal activity than the acetone extracts. The ethanol extract from the leaves and flowers of Calpurnia aurea had the best activity [corrected mortality (CM)=82.9%] which was followed by the stem extract of Cissus quadrangularis (CM=80.4%). The plant species were screened against Vero cells and were found to have low toxicity. From this study it is apparent that there is potential for the development of botanicals as natural acaricides against R. (B.) decoloratus. PMID:27270388

  14. Acaricidal Activity of Petroleum Ether Extract of Leaves of Tetrastigma leucostaphylum (Dennst. Alston against Rhipicephalus (Boophilus annulatus

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    T. P. Adarsh Krishna

    2014-01-01

    Full Text Available The acaricidal activity of the petroleum ether extract of leaves of Tetrastigma leucostaphylum (Dennst. Alston (family: Vitaceae against Rhipicephalus (Boophilus annulatus was assessed using adult immersion test (AIT. The per cent of adult mortality, inhibition of fecundity, and blocking of hatching of eggs were studied at different concentrations. The extract at 10% concentration showed 88.96% inhibition of fecundity, 58.32% of adult tick mortality, and 50% inhibition of hatching. Peak mortality rate was observed after day 5 of treatment. Mortality of engorged female ticks, inhibition of fecundity, and hatching of eggs were concentration dependent. The LC50 value of the extract against R. (B. annulatus was 10.46%. The HPTLC profiling of the petroleum ether extract revealed the presence of at least seven polyvalent components. In the petroleum ether extract, nicotine was identified as one of the components up to a concentration of 5.4%. However, nicotine did not reveal any acaricidal activity up to 20000 ppm (2%. Coconut oil, used as diluent for dissolving the extract, did not reveal any acaricidal effects. The results are indicative of the involvement of synergistic or additive action of the bioactive components in the tick mortality and inhibition of the oviposition.

  15. Mitigation of Resistance Through Mixtures of Traditional Pesticides, Anti-tick Vaccines, and New Acaricides Developed by the Pharmaceutical Industry

    Science.gov (United States)

    Over the past 70 years, the southern cattle tick, Rhipicephalus (Boophilus) microplus, has developed resistance to every acaricide available for its control. Recently, populations of R. microplus have evolved simultaneous resistance to multiple classes of acaricides. These multi-resistant population...

  16. Acaricidal effect of Pelargonium roseum and Eucalyptus globulus essential oils against adult stage of Rhipicephalus (Boophilus) annulatus in vitro.

    Science.gov (United States)

    Pirali-Kheirabadi, Khodadad; Razzaghi-Abyaneh, Mehdi; Halajian, Ali

    2009-06-10

    In a laboratory trial, in west-central Iran, the acaricidal effects of the essential oils (EOs) prepared from two medicinal plants, i.e. Pelargonium roseum and Eucalyptus globulus on the adult stage of Rhipicephalus (Boophilus) annulatus were evaluated. For this purpose, the engorged females of R. (B) annulatus were exposed to two-fold serial dilutions of oils (0.31-5.0%) using a "dipping method" in vitro. The engorged ticks were immersed in different plant dilutions (eight per dilution) for 1min then each replicate was incubated in separate petri dishes at 26 degrees C and 80% relative humidity. The mortality rate for adult ticks exposed to different dilutions of P. roseum and E. globulus EO's showed a dose-dependent decrease. It was however significant only for the 2.5% and 5.0% dilutions of P. roseum EO, when compared to the non-treated control (P<0.05). The mass of produced eggs in adult female ticks exposed to both P. roseum and E. globulus EOs had decreased dose-dependently. It was significant for only 2.5% and 5.0% dilutions of P. roseum EO, comparing the non-treated control (P<0.05). The highest decrease in egg laying was reported for ticks treated with 5% dilutions of P. roseum (87.5%) and E. globosus (25%) (P<0.05). This is the first report that details the acaricidal activity of EO's obtained from P. roseum and E. globosus against R. (B) annulatus. The results show that both plants, particularly P. Roseum can be considered as potential candidates for biocontrol of R. (B) annulatus in the field.

  17. Protective action of Tagetes minuta (Asteraceae) essential oil in the control of Rhipicephalus microplus (Canestrini, 1887) (Acari: Ixodidae) in a cattle pen trial.

    Science.gov (United States)

    Andreotti, Renato; Garcia, Marcos Valério; Cunha, Rodrigo Casquero; Barros, Jacqueline Cavalcante

    2013-10-18

    The Rhipicephalus microplus tick is globally regarded as the most economically important ectoparasite of livestock, and the evolution of resistance to commercial acaricides among cattle tick populations is of great concern. The essential oil derived from Tagetes minuta may be efficacious against cattle tick infestation, and the results of a cattle pen trial using this essential oil for the control of ticks are reported here. The chemical composition of the essential oil was determined by GC-MS and NMR spectroscopy analyses, which revealed the presence of four major components in the essential oil. These components represent more than 70% of the essential oil: limonene (6.96%), β-ocimene (5.11%), dihydrotagetone (54.10%) and tagetone (6.73%). The results of the cattle pen trial indicated significant differences among the average values of the analyzed biological parameters, including the number of ticks, the average weight of the ticks, the average egg weight per engorged female and larval viability. Treatment with the T. minuta essential oil prepared in this study promoted significant effects on all biological indicators analyzed. Based on the biological indicators, the essential oil showed 99.98% efficacy compared to the control group when used at a 20% concentration. The results obtained in this study suggest that the T. minuta essential oil is a potential R. microplus tick control agent and may be used to mitigate the economic losses caused by tick infestation. PMID:23778081

  18. A new approach to characterization of the resistance of populations of Rhipicephalus microplus (Acari: Ixodidae) to organophosphate and pyrethroid in the state of Minas Gerais, Brazil.

    Science.gov (United States)

    Faza, Aline Pasqualini; Pinto, Isabella Silvestre Barreto; Fonseca, Isabela; Antunes, Gustavo Resende; Monteiro, Caio Márcio de Oliveira; Daemon, Erik; Muniz, Michelle de Souza; Martins, Marta Fonseca; Furlong, John; Prata, Márcia Cristina de Azevedo

    2013-08-01

    The monitoring of resistance of cattle tick populations in Brazil to the chemical bases in use is largely limited to investigation of the phenotypic profile. There are few studies investigating the role played by the genotypic profile in acaricide resistance in the country. Therefore, the aim of the present study was to carry out molecular characterization and trace out the genetic profile of populations of Rhipicephalus microplus with respect to resistance to the organophosphate and pyrethroid chemical groups. For that purpose, larvae were genotyped belonging to 587 populations for pyrethroids and 306 for organophosphates, using the polymerase chain reaction technique. It was found that 75.49% and 97.44% of the larvae studied showed resistance to the organophosphates and pyrethroids, respectively. Among the populations resistant to pyrethroids, 91.9% were heterozygotes, showing that most of the resistant populations have only one allele responsible for resistance. Therefore, it is possible to conclude that the genotyped populations have high resistance to organophosphates, and even more so to pyrethroids. This information is fundamental for understanding the mechanisms of resistance of R. microplus to acaricides, to enable improvement of control techniques. PMID:23639866

  19. Integrated control of an acaricide-resistant strain of the cattle tick Rhipicephalus microplus by applying Metarhizium anisopliae associated with cypermethrin and chlorpyriphos under field conditions.

    Science.gov (United States)

    Webster, Anelise; Reck, José; Santi, Lucélia; Souza, Ugo A; Dall'Agnol, Bruno; Klafke, Guilherme M; Beys-da-Silva, Walter O; Martins, João Ricardo; Schrank, Augusto

    2015-01-30

    The efficacy of the fungus Metarhizium anisopliae to control ticks has been shown in several in vitro experiments. However, few studies have been undertaken in field conditions in order to demonstrate the applicability of its use as a biological control of ticks and its combination with chemical acaricides. The aim of the present study was to evaluate the efficacy of M. anisopliae to control an acaricide-resistant strain of Rhipicephalus microplus under laboratory and field conditions. First, the compatibility of M. anisopliae strain (TIS-BR03) with commercial acaricides and its potential to control the cattle tick were evaluated in vitro. In general, acaricide treatments had mild effects on fungus viability. In the field experiment, the median of treatment efficacy with acaricide only, M. anisopliae only and combination of M. anisopliae with acaricide were 71.1%, 56.3% and 97.9%, respectively. There is no statistical difference between groups treated with M. anisopliae and acaricide alone. Thus, in this work we have demonstrated the applicability of M. anisopliae use associated or not with chemical acaricides on field conditions in order to control an acaricide-resistant strain of the cattle tick R. microplus. PMID:25577676

  20. Evaluation of the Efficacy of Acaricides Used to Control the Cattle Tick, Rhipicephalus microplus, in Dairy Herds Raised in the Brazilian Southwestern Amazon

    Directory of Open Access Journals (Sweden)

    Luciana G. Brito

    2011-01-01

    Full Text Available The adult immersion test (AIT was used to evaluate the efficacy of acaricide molecules used for control of Rhipicephalus microplus on 106 populations collected in five municipalities in the state of Rondônia in the Brazilian South Occidental Amazon region. The analysis of the data showed that the acaricide formulations had different efficacies on the tick populations surveyed. The synthetic pyrethroids (SPs acaricides were the least effective (48.35–76.84%, followed by SP + organophosphate (OP associations (68.91–81.47% and amidine (51.35–100%. For the macrocyclic lactones (MLs, the milbemycin (94.84–100% was the most effective, followed by spinosad (93.21–100% and the avermectins (81.34–100%. The phenylpyrazole (PZ group had similar efficacy (99.90% to the MLs. Therefore, SP acaricides, including associations with OP, and formulations based on amidine presented low in vitro efficacy to control the R. microplus populations surveyed.

  1. Partial selective treatment of Rhipicephalus microplus and breed resistance variation in beef cows in Rio Grande do Sul, Brazil.

    Science.gov (United States)

    Molento, Marcelo Beltrão; Fortes, Fernanda Silva; Buzatti, Andréia; Kloster, Fernando Staude; Sprenger, Lew Kan; Coimbra, Eliane; Soares, Luis Dorneles

    2013-02-18

    Rhipicephalus microplus infestation causes heavy losses in cattle. The majority of farmers control the cattle tick by using long-acting drugs throughout the year, which evidently increases selection pressure for drug resistance. Partial selective treatment (PST) may be used to directly reduce selection pressure by treating only the portion of the herd that is most infested. The objective of this work was to determine the effect of PST in two herds of beef cows and the effect of breed tolerance. The Santiago (n=306 animals) and the São Francisco de Assis (n=204 animals) herds were composed of up to eight pure breeds of Bos taurus and Bos indicus and their crosses and were evaluated during the first and second (8 months) tick generations. Ticks larger than 4.5mm were counted on one side of the animal, and the animals were treated when numbers exceeded 20 ticks per host. On both farms, the tick-tolerant breeds with a high proportion of B. indicus (Braford, Brangus, and Nellore) consistently carried fewer ticks than Charolais. The economical evaluation showed an average profit margin in the use of PST of 674.25% and 1394.5% on the Santiago and São Francisco de Assis farms, respectively, in comparison to all-herd treatment. These results indicate that PST is a reliable tool for health management and may be used as a standard protocol for tick control with significant economic benefits on farms. In addition, the maintenance of the highest possible tolerant/resilient breeds is also an essential factor that should be considered in today's more sustainable animal production systems. PMID:23219046

  2. ALS - resources

    Science.gov (United States)

    Resources - ALS ... The following organizations are good resources for information on amyotrophic lateral sclerosis : Muscular Dystrophy Association -- mda.org/disease/amyotrophic-lateral-sclerosis National Amyotrophic Lateral Sclerosis (ALS) Registry -- ...

  3. In vitro establishment of ivermectin-resistant Rhipicephalus microplus cell line and the contribution of ABC transporters on the resistance mechanism.

    Science.gov (United States)

    Pohl, Paula C; Carvalho, Danielle D; Daffre, Sirlei; Vaz, Itabajara da Silva; Masuda, Aoi

    2014-08-29

    The cattle tick Rhipicephalus microplus is one of the most economically damaging livestock ectoparasites, and its widespread resistance to acaricides is a considerable challenge to its control. In this scenario, the establishment of resistant cell lines is a useful approach to understand the mechanisms involved in the development of acaricide resistance, to identify drug resistance markers, and to develop new acaricides. This study describes the establishment of an ivermectin (IVM)-resistant R. microplus embryonic cell line, BME26-IVM. The resistant cells were obtained after the exposure of IVM-sensitive BME26 cells to increasing doses of IVM in a step-wise manner, starting from an initial non-toxic concentration of 0.5 μg/mL IVM, and reaching 6 μg/mL IVM after a 46-week period. BME26-IVM cell line was 4.5 times more resistant to IVM than the parental BME26 cell line (lethal concentration 50 (LC50) 15.1 ± 1.6 μg/mL and 3.35 ± 0.09 μg/mL, respectively). As an effort to determine the molecular mechanisms governing resistance, the contribution of ATP-binding cassette (ABC) transporter was investigated. Increased expression levels of ABC transporter genes were found in IVM-treated cells, and resistance to IVM was significantly reduced by co-incubation with 5 μM cyclosporine A (CsA), an ABC transporter inhibitor, suggesting the involvement of these proteins in IVM-resistance. These results are similar to those already described in IVM-resistant tick populations, and suggest that similar resistance mechanisms are involved in vitro and in vivo. They reinforce the hypothesis that ABC transporters are involved in IVM resistance and support the use of BME26-IVM as an in vitro approach to study acaricide resistance mechanisms. PMID:24956999

  4. Comparison of 3 tests to detect acaricide resistance in Boophilus decoloratus on dairy farms in the Eastern Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    S. Mekonnen

    2003-06-01

    Full Text Available The susceptibility of the larval offspring of engorged female Boophilus decoloratus, and of the engorged females, collected from cattle on the dairy farms Brycedale, Sunny Grove and Welgevind in the Eastern Cape Province, South Africa, was tested against the acaricides amitraz, chlorfenvinphos and cypermethrin. Resistance was determined by means of the Shaw Larval Immersion Test (SLIT for larvae and the Reproductive Estimate Test (RET and Egg Laying Test (ELT for adults. At Brycedale the tests all indicated resistance to chlorfenvinphos, and RET and ELT indicated resistance to amitraz and emerging resistance to cypermethrin. At Sunny Grove, B. decoloratus was resistant to cypermethrin using SLIT and exhibited emerging resistance to chlorfenvinphos with SLIT and to cypermethrin with both RET and ELT. At Welgevind, resistance was recorded against chlorfenvinphos (SLIT and against cypermethrin (ELT, and emerging resistance against permethrin (RET. The results obtained with RET and ELT were generally comparable, but often differed from those obtained with SLIT. Resistance could be detected within 7 days with ELT compared to 42 days with RET and 60 days with SLIT.

  5. DETECTION OF EHRLICHIA SP. ISOLATED FROM THE TICK BOOPHILUS MICROPLUS OF TIBET BY SEQUENCE ANALYSIS OF 16S rRNA GENES%用16S rRNA基因序列分析从西藏的微小牛蜱中检出的埃立克体

    Institute of Scientific and Technical Information of China (English)

    温博海; 蹇锐; 张有植

    2003-01-01

    用埃立克体属特异性套式PCR和DNA序列测定从西藏微小牛蜱检出边缘无形体和埃立克体;用半套式PCR扩得该埃立克体的16S rRNA基因,并测定了它的序列;将该埃立克体的16S rRNA基因序列与其它埃立克体的16S rRNA基因序列进行对比分析,结果证明它的16S rRNA基因与埃立克体属的犬埃立克体群16S rRNA基因相似水平最高(97%~98%);用16S rRNA基因序列做系统发育分析,结果显示该采自西藏的微小牛蜱的埃立克体可能是与查菲埃立克体密切相关的一种新埃立克体.

  6. 新疆南疆微小牛蜱Bm86/Bm91双基因原核表达载体的构建%Construction of Prokaryotic Expression Vector of Bm86 and Bm91 Dual Genes of Boophilus microplus in South Xinjiang

    Institute of Scientific and Technical Information of China (English)

    代艳艳; 赵丽; 周桐; 罗福江; 周玉琴; 王帅; 刘永宏

    2014-01-01

    为构建微小牛蜱Bm86和Bm91双基因原核表达载体,以新疆生产建设兵团塔里木畜牧科技重点实验室获得的Bm86和Bm91克隆基因阳性菌或质粒DNA为模板,参照GenBank登录的微小牛蜱Bm86和Bm91基因序列和所用载体序列,设计可以扩增Bm86和Bm91基因完整阅读框架的引物,然后对新疆南疆微小牛蜱Bm86和Bm91基因进行PCR扩增、纯化、酶切后连接,构建双基因重组质粒pET-32a-Bm并鉴定.结果显示,成功构建Bm86和Bm91双基因重组质粒pET-32a-Bm,经测序鉴定和初始获得的Bm86和Bm91基因序列一致,未发生变异.

  7. Bm86 homologues and novel ATAQ proteins with multiple epidermal growth factor (EGF)-like domains from hard and soft ticks ☆

    OpenAIRE

    Nijhof, Ard M; Balk, Jesper A.; Postigo, Milagros; Rhebergen, Anne Marie; Taoufik, Amar; Jongejan, Frans

    2010-01-01

    Tick control on livestock relies principally on the use of acaricides but the development of acaricide resistance and concerns for environmental pollution underscore the need for alternative control methods, for instance through the use of anti-tick vaccines. Two commercial vaccines based on the recombinant Bm86 protein from Rhipicephalus (Boophilus) microplus ticks were developed. Partial protection of the Bm86 vaccine against other Rhipicephalus (Boophilus) and Hyalomma tick species suggest...

  8. AL Amyloidosis

    Directory of Open Access Journals (Sweden)

    Desport Estelle

    2012-08-01

    Full Text Available Abstract Definition of the disease AL amyloidosis results from extra-cellular deposition of fibril-forming monoclonal immunoglobulin (Ig light chains (LC (most commonly of lambda isotype usually secreted by a small plasma cell clone. Most patients have evidence of isolated monoclonal gammopathy or smoldering myeloma, and the occurrence of AL amyloidosis in patients with symptomatic multiple myeloma or other B-cell lymphoproliferative disorders is unusual. The key event in the development of AL amyloidosis is the change in the secondary or tertiary structure of an abnormal monoclonal LC, which results in instable conformation. This conformational change is responsible for abnormal folding of the LC, rich in β leaves, which assemble into monomers that stack together to form amyloid fibrils. Epidemiology AL amyloidosis is the most common type of systemic amyloidois in developed countries with an estimated incidence of 9 cases/million inhabitant/year. The average age of diagnosed patients is 65 years and less than 10% of patients are under 50. Clinical description The clinical presentation is protean, because of the wide number of tissues or organs that may be affected. The most common presenting symptoms are asthenia and dyspnoea, which are poorly specific and may account for delayed diagnosis. Renal manifestations are the most frequent, affecting two thirds of patients at presentation. They are characterized by heavy proteinuria, with nephrotic syndrome and impaired renal function in half of the patients. Heart involvement, which is present at diagnosis in more than 50% of patients, leading to restrictive cardiopathy, is the most serious complication and engages prognosis. Diagnostic methods The diagnosis relies on pathological examination of an involved site showing Congo red-positive amyloid deposits, with typical apple-green birefringence under polarized light, that stain positive with an anti-LC antibody by immunohistochemistry and

  9. Immunization of cattle with Ra86 impedes Rhipicephalus appendiculatus nymphal-to-adult molting

    NARCIS (Netherlands)

    Olds, C.; Mwaura, S.; Crowder, D.; Odongo, D.; Oers, van M.M.; Owen, J.; Bishop, R.; Daubenberger, C.

    2012-01-01

    Commercial vaccines based on the tick gut protein Bm86 have been successful in controlling the one-host tick Rhipicephalus (Boophilus) microplus and provide heterologous protection against certain other non-target ixodid tick species. This cross protection, however, does not extend to the three-host

  10. Evidence for the role of white-tailed deer(Artiodactyla:Cervidae)in the epidemiology of cattle ticks and southern cattle ticks (Acari:Ixodidae)in reinfestations along the Texas/Mexico border in South Texas-A review and update

    Science.gov (United States)

    From 1907 when the fever tick eradication campaign began until 1933 the tick eradication methods of dipping cattle in an acaricide or "pasture vacation" were enormously successful in eradicating southern cattle ticks [SCT, Rhipicephalus (Boophilus) microplus (Canestrini)], until failures began to oc...

  11. Integration of ecologically-based approaches to re-eradicate cattle fever ticks from the U.S.

    Science.gov (United States)

    Here we summarize highlights of research conducted as part of a NIFA-AFRI funded grant. Cattle fever ticks, Rhipicephalus (Boophilus) microplus and R. (B.) annulatus, have been found on white-tailed deer (Odocoileus virginianus) complicating eradication efforts of the USDA’s Cattle Fever Tick Eradic...

  12. Bm86 midgut protein sequence variation in south Texas cattle fever ticks

    Science.gov (United States)

    Cattle fever ticks, Rhipicephalus (Boophilus) microplus and R. (B.) annulatus, vector bovine and equine babesiosis, and have significantly expanded beyond the permanent quarantine zone established in South Texas. Currently, there are no vaccines approved for use within the United States for controll...

  13. Amyotrophic Lateral Sclerosis (ALS)

    Science.gov (United States)

    ... benefit of 16 months before onset of severe respiratory failure. Other treatments are designed to relieve symptoms and ... of ALS. Most people with ALS die from respiratory failure, usually within 3 to 5 years from the ...

  14. Volver al desarrollo

    Directory of Open Access Journals (Sweden)

    Jaime Ornelas Delgado

    2012-01-01

    Full Text Available El desarrollo, categoría empleada para expresar el crecimiento económico, surge durante la "guerra fría" y si bien fue propuesta por teóricos metropolitanos, se asumió en Latinoamérica como parte de los instrumentos disponibles para lograr el crecimiento y alternativa al socialismo. El desarrollo mantuvo su vigencia entre 1945 y 1975, cuando al advenimiento del neoliberalismo fue paulatinamente retirado de la agenda de las preocupaciones nacionales e internacionales. Al iniciarse el siglo xxi, el fracaso del mercado autorregulado trajo de nueva cuenta al debate los problemas del desarrollo, lo que obliga a revisarlo críticamente, tanto como al concepto mismo para mostrar su carácter colonial, si se quiere construir caminos ajenos al neoliberal y superar los problemas que han hecho de Latinoamérica una de las regiones más desiguales del mundo.

  15. Jalta als Heterotopie

    OpenAIRE

    Schmid, Ulrich

    2013-01-01

    Jalta ist ein Ort, der sich im europäischen Kulturgedächtnis sowohl historisch als auch literarisch als "radikal anderer Ort" - als " Heterotopie" - festgesetzt hat. An der Konferenz von Jalta wurde 1945 eine neue Weltordnung geschaffen in der Hoffnung auf eine bessere Welt. Auch in den Werken von Anton ?echov, vor allem in denjenigen, die in Jalta entstanden sind, wird von einer anderen und besseren Welt geträumt.

  16. Pornographie als Metapher

    OpenAIRE

    Caroline Schubarth

    2010-01-01

    In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.This article...

  17. Pornographie als Metapher

    Directory of Open Access Journals (Sweden)

    Caroline Schubarth

    2010-02-01

    Full Text Available In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.

  18. Protective efficacy of bacterial membranes containing surface-exposed BM95 antigenic peptides for the control of cattle tick infestations.

    Science.gov (United States)

    Canales, Mario; Labruna, Marcelo B; Soares, João F; Prudencio, Carlos R; de la Fuente, José

    2009-12-01

    The Rhipicephalus (Boophilus) microplus BM86 and BM95 glycoproteins are homologous proteins that protect cattle against tick infestations. In this study, we demonstrated that the recombinant chimeric protein comprising tick BM95 immunogenic peptides fused to the A. marginale MSP1a N-terminal region for presentation on the Escherichia coli membrane was protective against R. microplus infestations in rabbits. This system provides a novel and simple approach for the production of tick protective antigens by surface display of antigenic protein chimera on live E. coli and suggests the possibility of using recombinant bacterial membrane fractions for vaccination against cattle tick infestations. PMID:19835826

  19. Gezondheid als marketinginstrument

    NARCIS (Netherlands)

    Vijver, van de L.P.L.; Berg, van den I.

    2008-01-01

    Is biologisch voedsel beter dan gangbaar? Hoe hard zijn de bewijzen daarvoor? En hoe sterk moet het bewijs zijn voordat je het als claim op een product mag zetten? In dit Biokennis bericht een overzicht van de wetenschappelijke conclusies en de mogelijkheden om biologisch te promoten als beter, neer

  20. Al-Anon/Alateen

    Science.gov (United States)

    Find an Al-Anon meeting Español | Français 2018 Int'l Convention Home About Group Meetings What If I'm not ready ... a meeting? What can I expect at an Al-Anon meeting? What was my first meeting like? ...

  1. Al - BASED CAST COMPOSITES

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Yadav

    2011-08-01

    Full Text Available The economy is very important feature nowadays in themarket. The researches are playing an important role inengineering field to increase the life of machine parts /components and decrease the cost. The compositematerials have the potential to replace widely used steeland aluminium due to their good characteristics withbetter performance. The Al-based composites have foundextensive applications in automobile industries andaerospace industries due to their increased stiffness,strength, thermal conductivity and wear resistanceproperties. A number of particulate phases have beenemployed in the Al-alloy matrix. The cast aluminiumceramicparticulate composites are finding applications inpistons, connecting rods, cylinder liner, engine cylinderblock, electrical contacts etc.The present investigation isbased on study of the effect of particulate phase on theSEM study, micro-hardness, elastic modulus, tensilestrength and the wear behaviour of Al-5 % SiC-7 % Fe,Al-10 % SiC-6 % Fe and Al-15 % SiC-5 % Fe composites.

  2. Sociale media als leermiddel

    NARCIS (Netherlands)

    Rubens, Wilfred

    2012-01-01

    Rubens, W. (2012, 5 juni). Sociale media als leermiddel. Presentatie over het gebruik van sociale media binnen het onderwijs, verzorgd tijdens een ouderraadbijeenkomst van de Katholieke Scholengemeenschap Etten-Leur, Etten-Leur, Nederland.

  3. MDA ALS Caregiver's Guide

    Science.gov (United States)

    ... R.D., C.N.S.D., L.D.N. Nutritionist MDA/ALS Center at Vanderbilt University Medical Center ... neurologists, physiatrists, therapists (physical, occupa- tional, speech, respiratory), nutritionists, social work- ers, pulmonologists, gastroenterologists and medical equipment ...

  4. Regionale Herkunft als Bonus

    OpenAIRE

    Kratochvil, Dr. Ruth

    2004-01-01

    Der Bio-Sektor durchlebt bewegte Zeiten. Die biologische Landwirtschaft hat sich aus der Nische herausbewegt und dafür an „Besonderheiten“ eingebüßt. Diese müssen als Zusatznutzen wiedergefunden werden.

  5. Partizipation als Ausnahmezustand

    OpenAIRE

    Korf, Benedikt

    2009-01-01

    In «Die Erfindung des Politischen» (1993) beschreibt Ulrich Beck Subpolitik als den Ort, an dem die Grenze zwischen Politik und Nichtpolitik verschwindet. Aus der zunehmenden Wirkkraft von Subpolitik erwächst die grundlegende Frage, mit welcher Legitimation diese Art von Subpolitik in die Sphäre der institutionalisierten Politik eindringt. Beck’s Subpolitik soll im Anschluss an theoretische Arbeiten von Chantal Mouffe und Giorgio Agamben als post-politische Aspiration bezeichnet werden, die e...

  6. Der Preis als Kaufbarriere?

    DEFF Research Database (Denmark)

    Mueller Loose, Simone

    2012-01-01

    Die Preispolitik hat eine herausragende Stellung im Marketing. Der Preis eines Produktes ist für Verbraucher ein direkter Kostenfaktor und für Unternehmen die Stellgröße im Mar-ketingmix, die den Umsatz am stärksten beeinflusst (vgl. Nieschlag et al. 2002). Wenn die Akzeptanz und der regelmäßige...... Verzehr gesunder Lebensmittel erhöht werden soll, ist es sowohl für die Verbraucherpolitik als auch für Lebensmittelproduzenten wichtig, den Ein-fluss des Preises auf die Kaufentscheidung zu verstehen. Aus Verbrauchersicht ist der Preis neben dem Geschmack die wichtigste Produkteigen-schaft beim Kauf von...... Lebensmitteln (vgl. Brunsø/Grunert 1998) und stellt eine Kaufbarrie-re für Lebensmittel mit gesundheitsfördernden Eigenschaften dar. Studien in den USA (vgl. Cassady et al. 2007), Frankreich (vgl. Drewnowski et al. 2004; Andrieu et al. 2005) und Deutschland (vgl. Karg et al. 2008) kommen übereinstimmend zu dem...

  7. Genome wide scan for quantitative trait loci affecting tick resistance in cattle (Bos taurus × Bos indicus)

    OpenAIRE

    Machado, Marco Antonio; S Azevedo, Ana Luisa; Teodoro, Roberto L; Pires, Maria A; CD Peixoto, Maria Gabriela; de Freitas, Célio; Prata, Márcia Cristina A; Furlong, John; da Silva, Marcos Vinicius GB; Guimarães, Simone EF; Regitano, Luciana CA; Coutinho, Luiz L.; Gasparin, Gustavo; Verneque, Rui S

    2010-01-01

    Background In tropical countries, losses caused by bovine tick Rhipicephalus (Boophilus) microplus infestation have a tremendous economic impact on cattle production systems. Genetic variation between Bos taurus and Bos indicus to tick resistance and molecular biology tools might allow for the identification of molecular markers linked to resistance traits that could be used as an auxiliary tool in selection programs. The objective of this work was to identify QTL associated with tick resista...

  8. Haplotypes that include the integrin alpha 11 gene are associated with tick burden in cattle

    OpenAIRE

    Bunch Rowan J; Porto Neto Laercio R; Harrison Blair E; Prayaga Kishore C; Barendse William

    2010-01-01

    Abstract Background Infestations on cattle by the ectoparasite Boophilus (Rhipicephalus) microplus (cattle tick) impact negatively on animal production systems. Host resistance to tick infestation has a low to moderate heritability in the range 0.13 - 0.64 in Australia. Previous studies identified a QTL on bovine chromosome 10 (BTA10) linked to tick burden in cattle. Results To confirm these associations, we collected genotypes of 17 SNP from BTA10, including three obtained by sequencing part...

  9. Growing hairs in shorn cattle

    OpenAIRE

    Cecília José Veríssimo; Selma D'Agostino; Fernanda Pessoa; Luciandra Macedo Toledo; Keila Maria Roncato Duarte

    2013-01-01

    The shearing operation can provide double benefits to the cattle: they can become more heat tolerant and the tick infestation decreases. The cattle tick Rhipicephalus (Boophilus) microplus causes great losses to dairy cattle, especially to the Holstein cattle because they are very susceptible to this tick. Its control is becoming each day more difficult, owing to the increasing resistance to acaricides they are acquiring. The objective of this work was to study the growing of haircoat followi...

  10. Impact of Babesia bovis and Babesia bigemina on the production of beef cattle in Uruguay

    OpenAIRE

    M. A. Solari; A. Nari; H. Cardozo

    1992-01-01

    Uruguay is situated in a marginal area for the development of Boophilus microplus (30- 35- South Lat.) with important areas of enzootic instability for Babesia bovis and B. bigemina. The livestock products represent 70% of our exports, for wich reason it is fundamental to evaluate the losses in the production that these haemoparasites cause as basic information to take future decisions. In the period 1988-1990, several works were carried out by our laboratory to know the incidence of babesios...

  11. Experimental vaccination of sheep and cattle against tick infestation using recombinant 5′-nucleotidase

    OpenAIRE

    Hope, M.; Jiang, X.; Gough, J.; CADOGAN, L; JOSH, P; Jonsson, N.; P. Willadsen

    2010-01-01

    Limited prior evidence suggests that 5′-nucleotidase, an ectoenzyme principally located in the Malpighian tubules of the tick Rhipicephalus (Boophilus) microplus, could be an effective antigen in an anti-tick vaccine. To assess this, recombinant 5′-nucleotidase was expressed in Escherichia coli and used in vaccination trials with both sheep and cattle. Vaccinated sheep were challenged with freshly moulted adult ticks. Those with high titres of anti-nucleotidase antibodies showed significant p...

  12. Immunization and chemical conjugation of Bm95 obtained from Pichia pastoris enhances the immune response against vaccinal protein and Neisseria meningitidis capsular polysaccharide

    OpenAIRE

    Rodriguez Valle, Manuel

    2014-01-01

    Manuel Rodriguez-Valle,1 Leonardo Canan-Hadden,2 Olivia Niebla2 1Animal Biotechnology Division, 2Analytical Division, Centre for Genetic Engineering and Biotechnology, Havana, Cuba Abstract: The ectoparasite Rhipicephalus (Boophilus) microplus causes severe economic losses to the cattle industry in tropical and subtropical regions, and transmits endoparasites, such as Babesia bovis. The glycoprotein Bm95 is homologous to Bm86, a surface membrane protein of gut epithelial cells in R. microplu...

  13. Bm86 midgut protein sequence variation in South Texas cattle fever ticks

    OpenAIRE

    Kammlah Diane M; Kappmeyer Lowell S; Davey Ronald B; Freeman Jeanne M; Olafson Pia U

    2010-01-01

    Abstract Background Cattle fever ticks, Rhipicephalus (Boophilus) microplus and R. (B.) annulatus, vector bovine and equine babesiosis, and have significantly expanded beyond the permanent quarantine zone established in South Texas. Currently, there are no vaccines approved for use within the United States for controlling these vectors. Vaccines developed in Australia and Cuba based on the midgut antigen Bm86 have variable efficacy against cattle fever ticks. A possible explanation for this v...

  14. The evaluation of yeast derivatives as adjuvants for the immune response to the Bm86 antigen in cattle

    OpenAIRE

    Machado Héctor; Montero Carlos; Rodríguez Valle Manuel; Joglar Marisdania

    2001-01-01

    Abstract Background The Gavac™ vaccine against the cattle tick Boophilus microplus has proven its efficacy in a large number of controlled and field experiments. However, this vaccine could be further improved by searching for new alternative adjuvants that would induce a stronger long-lasting immune response. We conducted several experiments to assay the adjuvant effect of fractions of the recombinant yeast Pichia pastoris in mouse and cattle models. In previous experiments, the combination ...

  15. Tick loads in Bos taurus cattle grazing in two contrasting production systems

    OpenAIRE

    Raquel Salazar B; Rolando Barahona-Rosales; María-Solange Sánchez P

    2016-01-01

    Objectives. To relate the effect of biotic and abiotic factors on Rhipicephalus (Boophilus) microplus tick loads on cows grazing either in intensive silvopastoral systems (ISS) (Lucerna) or in grass pastures associated with sugarcane plantations (La Isabela). Materials and methods. Tick counts were performed on 27 Lucerne breed animals that were in different physiological states, six of which were grazing on forage grass paddocks associated with commercial sugarcane plantations and the remain...

  16. AcEST: BP914537 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 1.8 sp|Q86RN8|MYSP_BOOMI Paramyosin OS=Boophilus microplus GN=PRM PE... 32 1.8 sp|P18042|POL_HV2G...+ A S+T E+ Sbjct: 57 EKSDLTVQLMQ------LSDRLEEAEGSSETVVEM 85 >sp|P18042|POL_HV2G1 Gag-Pol polyprotein OS=Huma

  17. Modification of residual stress in Al-[AlBO]w/Al compound plate

    Institute of Scientific and Technical Information of China (English)

    姜传海; 吴建生; 王德尊

    2001-01-01

    The application of compound parts of Al-[AlBO]w/Al not only reduces the cost of the parts but also improves its properties. However, there is a large thermal residual stress between Al and [AlBO]w/Al, and it is harmful for practical application. From the theoretical analyses and experimental results, it was found that by the compressive pre-plastic deformation perpendicular to the interface between Al and [AlBO]w/Al, the interlayer residual stress of compound parts can be reduced, while the mechanical properties of compound parts can be improved.

  18. Fortschritt als Fortschrittsdiskurs

    Directory of Open Access Journals (Sweden)

    Rainer Schmid-Zartner

    2014-12-01

    Full Text Available Zur Erzielung gesellschaftlichen Fortschritts in demokratisch verfassten Gesellschaften soll die Möglichkeit am Fortschrittsdiskurs teilnehmen zu können für alle Mitglieder der Gesellschaft als selbstverständliche Prämisse gelten. Fortschritt wird also als Bewusstseinsbildung dem Fortschritt selbst gegenüber und als Entscheidungs- und Handlungsfähigkeit auf individueller und gesellschaftlicher Ebene definiert. Dies setzt entsprechende Maßnahmen zur Befähigung dazu voraus, die alle Mitglieder der Gesellschaft erfassen. Dabei ist der Bildungsbereich angesprochen, insbesondere der Schulunterricht. Neben dem in der aktuellen blidungspolitischen Debatte forcierten Fokus auf den Aspekt der Kompetenzorientierung, der hier nicht infrage gestellt wird, ist als notwendige Ergänzung ein reflexionsorientierter Schulunterricht in allen Bildungsfächern einzufordern und umzusetzen. Im Weiteren beschreibt der Text den Weg von der Brauchbarkeit zur Bedeutsamkeit von schulischem Wissen durch Relevanzreflexionsprovokationen im Schulunterricht, um Sinn und Bedeutung der vermittelten Bildungsinhalte zu verhandeln. Am Beispiel von Mathematik als Bildungsfach wird der Inhalt von reflexionsorientertem Unterricht verdeutlicht. Darüber hinaus beschreibt der Text eine Reihe von konkreten Fallbeispielen aus der aktuell versuchsweise durchgeführten Unterrichtspraxis in Mathematik.

  19. Pornographie als Metapher

    Directory of Open Access Journals (Sweden)

    Caroline Schubarth

    2010-03-01

    Full Text Available In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.This article examines different metaphorical uses of the term pornography and the resulting implications. While the existence of pornography for the feminist anti-porno movement serves as factor in the continuing discrimination of women in western societies, conservative powers on the right use the allegation of pornography as a justification for censorship of those identities and sexual practices deemed deviant.

  20. Wikipedia als Referenzorgan

    OpenAIRE

    Voß, Jakob

    2006-01-01

    Wikipedia wird inzwischen von vielen Nutzern regelmäßig als Nachschlagewerk genutzt. Aufgrund des offenen Charakters der Online-Enzyklopädie, bei der sich jeder direkt beteiligen kann, ist jedoch zusätzliche Medienkompetenz notwendig, um die Qualität einzelner Wikipedia-Artikel einschätzen zu können. Im Vortrag sollen Methoden zur Beurteilung von Wikipedia-Artikeln dargestellt und die Frage beleuchtet werden, unter welchen Umständen Wikipedia als Referenzorgan geeignet ist.

  1. Carta al Editor

    Directory of Open Access Journals (Sweden)

    José Andrés Burgos Zuleta

    2010-06-01

    Full Text Available La medicina al basarse generalmente en la clínica, correlacionaexámenes complementarios y organiza un diagnóstico y tratamiento, es una disciplina donde es imprescindible saber recolectar, analizar, interpretar y concretar una respuesta adecuada, es así que la información que se recibe es esencial para el desempeño médico.La certeza es una realidad que se da en algunas situaciones y enotras las probabilidades establecen conclusiones. Lo normal muchas veces se define sobre la base de criterios estadísticos, basados en riesgos poblacionales que no necesariamente se aplican al caso boliviano.

  2. Calculation of interaction of AlCl, AlCl2 and AlCl3 on Al4C3 (001) Al4CO4 (001) and Al2CO (001) planes

    Institute of Scientific and Technical Information of China (English)

    段少飞; 陈秀敏; 杨斌; 郁青春; 徐宝强; 刘大春

    2015-01-01

    To make sure the intermediate products of the carbothermic reduction of Al2O3 process, such as Al4CO4, Al2CO and Al4C3, and the interaction of AlCl, AlCl2, AlCl3 with Al4CO4, Al2CO and Al4C3, respectively, thermodynamic analyses were used to study the chloride reaction production of them under the vacuum situation. The stable structures and electronic properties of AlCl, AlCl2 and AlCl3 adsorbed on Al4CO4, Al2CO and Al4C3 were calculated by first-principles calculations by the CASTEP module in the Materials Studio program. The results show that the AlCl3 and AlCl2 molecules have decomposed on the plane of Al4C3 (001), while there are no obvious decomposition of AlCl3 and AlCl2 on Al4CO4 (001) and Al2CO (001) planes. The adsorption of AlCl on the Al4CO4 (001) and Al2CO (001) planes is stronger than that on the Al4C3(001) plane. The interaction strength of AlCl3, as well as AlCl2, with Al4CO4, Al2CO and Al4C3 is in the sequence of Al4CO4Al2CO>Al4C3.

  3. Comentarios al Salto Social

    Directory of Open Access Journals (Sweden)

    Facultad de Ciencias Económicas

    1995-06-01

    Full Text Available 1. El Plan considera que la política social es un componente central de la estrategia macroeconómica. A diferencia de la administración Gaviria, lo social ha dejado de ser un asunto marginal, es consustancial al desarrollo y, por tanto, se le confiere una dimensión cualitativamente diferente.

  4. Slowenisch als fremdsprache

    Directory of Open Access Journals (Sweden)

    Jože Toporišič

    1981-12-01

    Full Text Available Nicht ganz zwei Millionen Menschen sprechen Slowenisch als Muttersprache. Wenige gibt es, die das Slowenische zwar spre­ chen oder zu sprechen versuchen, aber eine andere Muttersprache haben, vielleicht hunderttausend; für die ist Slowenisch also eine Fremdsprache.

  5. ALS insertion devices

    International Nuclear Information System (INIS)

    The Advanced Light Source (ALS), the first US third generation synchrotron radiation source, is currently under construction at the Lawrence Berkeley Laboratory. The low-emittance, 1.5 GeV electron storage ring and the insertion devices are specifically designed to produce high brightness beams in the UV to soft X-Ray range. The planned initial complement of insertion devices includes four 4.6 m long undulators, with period lengths of 3.9 cm, 5.0 cm (2) and 8.0 cm, and a 2.9 m long wiggler of 16 cm period length. Undulator design is well advanced and fabrication has begun on the 5.0 cm and 8.0 cm period length undulators. This paper discusses ALS insertion device requirements; general design philosophy; and design of the magnetic structure, support structure/drive systems, control system and vacuum system. 18 refs., 9 figs., 5 tabs

  6. De GPS al mapa

    Directory of Open Access Journals (Sweden)

    Esteban Dörries

    2016-03-01

    Full Text Available Las coordenadas Lambert obtenidas a partir de mediciones con equipos GPS de mano, llamados a veces navegadores, en ciertos casos confunden al usuario, por diferir claramente de su posición real al ser graficadas en un mapa del Instituto Geográfico Nacional (IGN: Esto puede resolverse con suficiente exactitud mediante una transformación de Molodensky, seguida de la correspondiente proyección cartográfica. Sin embargo, los tres parámetros necesarios para la transformación, supuestamente válidos para Costa Rica, se encuentran en muchas variantes y producen obviamente resultados diferentes. En este trabajo se analizan los fundamentos del problema y sus posibles soluciones, culminando con un estudio comparativo de ocho casos, que permite seleccionar los valores más adecuados para los parámetros.

  7. HA03 as an Iranian Candidate Concealed Antigen for Vaccination against Hyalomma anatolicum anatolicum: Comparative Structural and In silico Studies

    Directory of Open Access Journals (Sweden)

    Mohammadi, A.

    2013-12-01

    Full Text Available In the last decades researchers had focused on developing a vaccine against tick based on protective antigen. Recombinant vaccines based on concealed antigen from Boophilus microplus have been developed in Australia and Cuba by the name of TICKGARD and GAVAC (De La Fuente and Kocan, 2006. Further studies on this antigen have shown some extent of protection against other species (De Vos et al., 2001. In Iran most important species is Hyalomma anatolicum and limited information about its control are available. This paper reports structural and polymorphic analysis of HA03 as an Iranian candidate concealed antigen of H. a. anatolicum deposited in Gen-Bank .(Aghaeipour et al. GQ228820. The comparison between this antigen and other mid gut concealed antigen that their characteristics are available in GenBank showed there are high rate of similarity between them. The HA03 amino acid sequence had a homology of around 89%, 64%, 56% with HA98, BM86, BM95 respectively. Potential of MHC class I and II binding region indicated a considerable variation between BM86 antigen and its efficiency against Iranian H. a. anatolicum. In addition, predicted major of hydrophobisity and similarity in N-glycosylation besides large amount of cystein and seven EGF like regions presented in protein structure revealed that value of HA03 as a new protective antigen and the necessity of the development, BM86 homolog of H. a. anatolicum HA03 based recombinant vaccine.

  8. AL-IZDIWAJIYYAH AL-LUGHOWIYAH FII ISTIHDHAMI AL-LUGHOH AL-‘ARABIYAH

    OpenAIRE

    Imam Muslimin

    2011-01-01

    Al-Izdiwajiyyah (diglosia) is standardizing a specific language when there are two variants of language that live side by side in societal life and each variant has its own social function. Disglosia is related to the use of local languages variations of low language and high language in a community. In Arabic language, disglosia covers dialects among the speakers, for instance there are two variants of language that each has roles and functions. The use of the variant depends on the situatio...

  9. Carta al editor

    Directory of Open Access Journals (Sweden)

    Harry Pachajoa

    2012-02-01

    Full Text Available Recently, Valencia et al., published a very interesting article called «Lipid profile in a group of patients with Turner’s syndrome at Clínica Universitaria Bolivariana in the city of Medellín between 2000 and 2009". An article which evaluated lipid levels in patients withTurner syndrome in a Colombian clinic, the study associated results of lipid profile with karyotype and other risk factors for coronary heart disease.

  10. Carta al editor

    OpenAIRE

    Harry Pachajoa

    2012-01-01

    Recently, Valencia et al., published a very interesting article called «Lipid profile in a group of patients with Turner’s syndrome at Clínica Universitaria Bolivariana in the city of Medellín between 2000 and 2009". An article which evaluated lipid levels in patients withTurner syndrome in a Colombian clinic, the study associated results of lipid profile with karyotype and other risk factors for coronary heart disease.

  11. Modeling neuronal vulnerability in ALS.

    Science.gov (United States)

    Roselli, Francesco; Caroni, Pico

    2014-08-20

    Using computational models of motor neuron ion fluxes, firing properties, and energy requirements, Le Masson et al. (2014) reveal how local imbalances in energy homeostasis may self-amplify and contribute to neurodegeneration in ALS.

  12. AL-USRCRN Station Information

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Documentation of United States Alabama Regional Climate Reference Network (AL-USRCRN) installations in 2006. Installations documented are for AL-USRCRN pilot...

  13. ICT als medicijn tegen onveiligheid

    OpenAIRE

    Linders, Lilian; Steyaert, Jan

    2002-01-01

    Hoe verhoudt ICT zich tot veiligheid? SQM zou niet 'ict oplossingen voor sociale kwesties' als ondertitel hebben, als we geen aandacht gaven aan deze vraag. In de eerste Rode Draad Notitie verkent SQM dit thema.

  14. Gliricidia sepium al establecimiento

    Directory of Open Access Journals (Sweden)

    J. L. Valle

    2004-01-01

    Full Text Available Se asoció Cenchrus ciliaris (Cc y Gliricidia sepium (Gs para evaluar la producción de biomasa y la composición química de los forrajes en la fase de establecimiento, en el estado de Morelos, México, en condiciones de trópico seco. Se empleó un análisis de varianza con diseño en bloques al azar, en donde T1 fue pasto solo, T2 Cc más Gs con 5,000 plantas ha-1 y el T3 Cs más Gs con 14,285 plantas ha-1. Se midió la producción de forraje individual y asociado con materia seca (t MS/Ha, la altura (A en cm, la proteína cruda (PC%, las fracciones de fibra (FDN% y FDA% y la digestibilidad in vitro de la materia seca (DIVMS%. El T3 tuvo una mejor producción de biomasa (P0.05. La asociación de 14,285 plantas ha-1 de G. sepium con pasto Cenchrus ciliaris mejoró la producción de biomasa y la disponibilidad total de nutrientes por superficie cultivada al establecimiento

  15. Derivados vinculados al seguro.

    Directory of Open Access Journals (Sweden)

    De Paz Cobo, Sonia

    2003-01-01

    Full Text Available El presente trabajo tiene como objetivo la presentación de los derivados financieros como instrumentos de cobertura de los riesgos del seguro, así como de los principales proyectos que se desarrollan a través de los mismos, como por ejemplo los derivados sobre el clima. Hay que tener presente las pérdidas multimillonarias ocasionadas en casos como el de la banca Baring’s, o el de Orange County, por citar algunas, que si bien ciertos autores afirman que están en relación directa con el uso de estos productos, no podemos olvidar que los instrumentos derivados se desarrollaron con el objetivo principal de proteger al usuario de la posible volatilidad del activo subyacente. Ya en la industria aseguradora los derivados vinculados a tal actividad son instrumentos donde el pago se condiciona a la ocurrencia de su suceso de siniestro, o serie de sucesos múltiples que disparen las pérdidas. Tras el repaso efectuado y la descripción que este tipo de instrumentos puede tener en la gestión del riesgo por parte de la industria aseguradora, concluiremos con la exposición de las relaciones con el reaseguro tradicional así como una breve referencia al futuro de este tipo de instrumentos

  16. Corrosion behaviour of Al/SiC and Al/Al2O3 nanocomposites

    Directory of Open Access Journals (Sweden)

    Tamer Samir Mahmoud

    2012-12-01

    Full Text Available In the present investigation, the static immersion corrosion behavior of Al/Al2O3 and Al/SiC nanocomposites in 1 M HCl acidic solution was evaluated. The nanocomposites were fabricated using conventional powder metallurgy (P/M route. The effect of nanoparticulates size and volume fraction on the corrosion behavior of nanocomposites was studied. The durations of the corrosion tests ranged from 24 to 120 hours and the temperatures of the solution ranged from ambient to 75 ºC. The corrosion rates of the nanocomposites were calculated using the weight loss method. The results showed that both Al/SiC and Al/Al2O3 MMNCs have lower corrosion rates than the pure Al matrix. Such behavior was noticed at both ambient and higher temperatures. Generally, the Al/Al2O3 nanocomposites exhibited lower corrosion rates than the Al/SiC nanocomposites. The Al/Al2O3 (60 nm nanocomposites exhibited the highest corrosion resistance among all the investigated nanocomposites. The corrosion rate was found to be reduced by increasing of the exposure time and the volume fraction of the nanoparticulates, while it was found to be increased by increasing of the nanoparticulates size and the solution temperature.

  17. Doppelthydrophile Blockcopolymere als Mineralisationstemplate

    Science.gov (United States)

    Kasparova, Pavla

    2002-07-01

    Die vorliegende Arbeit beschäftigt sich mit der Synthese und den Eigenschaften von doppelthydrophilen Blockcopolymeren und ihrer Anwendung in einem biomimetischen Mineralisationsprozeß von Calciumcarbonat und Bariumsulfat. Doppelthydrophile Blockcopolymere bestehen aus einem hydrophilen Block, der nicht mit Mineralien wechselwirkt und einem zweiten Polyelektrolyt-Block, der stark mit Mineraloberflächen wechselwirkt. Diese Blockcopolymere wurden durch ringöffnende Polymerisation von N-carboxyanhydriden (NCA's) und a-methoxy-ω-amino[poly(ethylene glycol)] PEG-NH2 als Initiator hergestellt. Die hergestellten Blockcopolymere wurden als effektive Wachstumsmodifikatoren für die Kristallisation von Calciumcarbonat und Bariumsulfat Mineralien eingesetzt. Die so erhaltenen Mineralpartikel (Kugeln, Hantel, eiförmige Partikel) wurden durch Lichtmikroskopie in Lösung, SEM und TEM charakterisiert. Röntgenweitwinkelstreuung (WAXS) wurde verwendet, um die Modifikation von Calciumcarbonat zu ermitteln und die Größe der Calciumcarbonat- und Bariumsulfat-Nanopartikel zu ermitteln. This work describes the synthesis and characterization of double hydrophilic block copolymers and their use in a biomimetic mineralization process of Calcium Carbonate and Barium Sulfate. Double hydrophilic block copolymers consist of a hydrophilic block that does not interact with minerals and another hydrophilic polyelectrolyte block that strongly interacts with mineral surfaces. These polymers were synthesised via ring opening polymerisation of N-carboxyanhydride (NCA), and the first hydrophilic block a-methoxy-ω-amino[poly(ethylene glycol)] PEG-NH2 was used as an initiator. The prepared block copolymers were used as effective crystal growth modifiers to control the crystallization of Calcium Carbonate and Barium Sulfate minerals. The resulting mineral particles (spheres, dumbbells, egg-like particles) were characterised by light microscopy in solution, by SEM, and by TEM. X-Ray scattering

  18. COMENTARIO AL CASO PINOCHET

    Directory of Open Access Journals (Sweden)

    Alberto Contreras Clunes

    2002-01-01

    Full Text Available El fallo en el caso Pinochet tiene distintas formas de ser analizado. De partida, desde un punto de vista político, también constitucional, del derecho penal. Sin embargo, nos abocaremos al estudio desde el punto de vista procesal, en especial a lo referido al Debido Proceso. Para ello se analizará los presupuestos, la solución dada por la Excma. Corte Suprema y las consecuencias del mismo. Además, se criticará la solución dada, desde la óptica de las garantías procesales del imputado, contenidas en el nuevo proceso penal y lo dispuesto en la Constitución y la Convención Americana de Derechos Humanos. Finalmente, se argumentará en favor de una interpretación finalista y armónica de la Constitución y los tratados internacionales de derechos humanos.The verdict of the Pinochet Case has different ways of being analyzed: from the political, the constitutional, and the penal law points of view. However, we will approach this study from the legal point of view, especially to that referred to as the Proper Process. To do this, the budgets, the solution given by the Most Excellent Supreme Court, and its consequences will be analyzed. Furthermore, the given solution will be criticized from the point of view of the legal guarantees of the accused contained in the new penal process and what is contained in the Constitution and in the American Convention of Human Rights. In conclusion, we will argue in favor of a final and harmonious interpretation of the Constitution and the international agreement of human rights.

  19. Epitaxial growth of Al/Al2O3 multilayer structures

    International Nuclear Information System (INIS)

    In order to obtain Al-Al2O3 quantum effect devices, it is necessary to deposit epitaxially Al on Al2O3 and Al2O3 on Al. We have already obtained an epitaxial Al/Al2O3/Al structures on Si(111). In this paper, we have deposit Al/Al2O3/Al structures on Si(111), and investigated the crystallinity by using RBS. (author)

  20. Effect of AlN Particulate Size on Superplasticity of AlNp/6061 Al Composites

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Superplastic tensile tests of AlNp/606l Al Composites, fabricated by powder metallurgy techniques, were performed at strain rates ranging from 10-1-10-3S-1 and at temperatures from 833 to 893 K. Hot rolling after extrusion was employed to obtain a fine grained structure before \\superplastic testing. The superplastic behavior of AlNp/6061 Al Composites was compared with that of AlN particulate size. Differential scanning calorimeter was used to ascertain the possibility of any partial melting in the vicinity of optimum superplastic temperatures.

  1. Editorial: Cartas al Editor

    Directory of Open Access Journals (Sweden)

    Guillermo Llanos

    2006-06-01

    Full Text Available En todas las revistas biomédicas del mundo existe una sección habitual denominada como el título de este editorial y que en Colombia Médica la llamamos correspondencia. Este espacio tiene como objetivo fundamental que los lectores escriban a los autores (investigadores comentando los artículos que se han publicado en números anteriores de la revista. Las cartas son, entonces, breves comentarios de desacuerdo o acuerdo (conceptual, metodológico, interpretativo sobre falencias ubicadas por un lector alerta al tema debatido en cualquiera de las secciones como en los artículos originales, editoriales, revisiones, presentación de casos, etc. publicados previamente en la revista. Las cartas deben permitir el intercambio de opiniones y formas de pensar y analizar los problemas planteados entre los autores y los lectores. En ocasiones una serie de cartas motivadas por un artículo original puede ser tan o más interesante como el artículo que generó la correspondencia. Las cartas son también un formato adecuado para comunicar un hecho novedoso de una observación clínica juiciosa no descrita antes. Un ejemplo de ello es la carta de un gineco-obstetra australiano cuando informó a Lancet los primeros efectos adversos informados de la talidomida. Colombia Médica, a pesar de mantener vigente esta sección, no ha sido muy afortunada en establecer una buena cultura del envío de cartas al editor. Pero últimamente han llegado juiciosas observaciones a las cuales se les ha dado prioridad en su publicación. Toda carta que comenta los hallazgos de un artículo es enviada a los autores para su respuesta, porque ello genera el debate académico buscado, y luego se publican, tanto la carta como su respuesta. El Estilo Vancouver recomienda que la carta y su respuesta deban ser breve, no pasar de dos o tres párrafos y contener sólo cuatro o cinco referencias. En lo posible (a menos que sea indispensable no presentar ni cuadros ni gráficos. El t

  2. Malamih al-Ashwat al-'Arabiyyah wa Makharijaha

    Directory of Open Access Journals (Sweden)

    Amrah Muhammad Kasim

    2015-12-01

    Full Text Available This writing discusses on al-ashwat al-‘arabiyyah that is known with “phonetic” term. It talks and interprets makharij al-huruf or place for producing sounds and also processing production of sounds by parts of mouth in Arabic language. The problems of sounds and its systems in Arabic language have been conducted by the scholars of al-ashwat al-‘arabiyyah attractively, neatly, and detail and gotten ahead the phonetic western scholars. Part of their analysis results formulate the study about al-ashwat al-sakinah (al-Shamit is known with vocal and consonant sounds in research questions shawait – shawamit. Ibnu Jinni has formulated “harakat”(wowel in Arabic language and dimension of letter  mad and liyn on alif  letter - waw - ya’ (ا و ي, from these letters create  harakat fathah, dammah, and kasrah. Moreover, in this writing also exist the description of hija’i letters and its makhraj that are correct from parts of mouth and the unity of coordinative sounds that produce sounds in morphemes arrangement, in one word that produces meaning. The result of phonological study has divided al-ashwat to be kinds of sound like the pronounced sounds, produced sounds from mouth, and heard sound.

  3. AL-IZDIWAJIYYAH AL-LUGHOWIYAH FII ISTIHDHAMI AL-LUGHOH AL-‘ARABIYAH

    Directory of Open Access Journals (Sweden)

    Imam Muslimin

    2011-10-01

    Full Text Available Al-Izdiwajiyyah (diglosia is standardizing a specific language when there are two variants of language that live side by side in societal life and each variant has its own social function. Disglosia is related to the use of local languages variations of low language and high language in a community. In Arabic language, disglosia covers dialects among the speakers, for instance there are two variants of language that each has roles and functions. The use of the variant depends on the situation. The most important characteristic of diglosia is specifying the functions of wach language variant. For high level language variant is aimed for formal situations such as religious ceremony, lectures, news, or editorials of newspaper. On the contrary, the low level language variant is commonly used in less formal situation such as daily communication in the family, chat with friends, stories in radion, and folk literature. In Arabic language, diglosia can be identified when the speaker of the language use diction commonly used for daily communication (amiyah in a formal expression (fusha, and vice versa.

  4. Al versus Si competition in FeSiAl alloys

    Energy Technology Data Exchange (ETDEWEB)

    Legarra, E. [Dpto. Electricidad y Electronica, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco (UPV/EHU), CP 644, 48080 Bilbao (Spain)], E-mail: estibaliz.legarra@ehu.es; Apinaniz, E. [Dpto. Fisica Aplicada I, Escuela de Ingenieria Tecnica Superior, Universidad del Pais Vasco, Alameda de Urquijo s/n 48013 Bilbao (Spain); Plazaola, F. [Dpto. Electricidad y Electronica, Facultad de Ciencia y Tecnologia, Universidad del Pais Vasco (UPV/EHU), CP 644, 48080 Bilbao (Spain); Jimenez, J.A. [Centro Nacional de Investigaciones Metalurgicas (CENIM), Avda. Gregorio del amo 8, 28040 Madrid (Spain); Pierna, A.R. [Chemical Engineering and Environmental Department, UPV/EHU, Box 1379, 20008 San Sebastian (Spain)

    2008-10-15

    In FeSiAl alloys, when Si substitutes for Al, important changes take place in the magnetism as well as in the structural properties. Alloys in the two composition series Fe{sub 75}Al{sub 25-x}Si{sub x} (x=0, 7.5, 12.5, 17.5, 25) and Fe{sub 70}Al{sub 30-x}Si{sub x} (x=0, 9, 15, 21, 30) were prepared by induction melting; afterwards they were crushed and then annealed in order to recover the DO{sub 3} stable phase. The deformed FeAl samples show larger lattice parameters than the ordered ones; however, this difference ({delta}a) decreases when Si substitutes for Al until it becomes zero (i.e. until the ordered samples and the deformed ones have the same lattice parameters). This trend is the same for both sample series and does not depend on the Fe content of the alloy. However, the magnetization has a different behaviour depending on the Fe content. For deformed Fe{sub 75}Al{sub 25-x}Si{sub x} alloys the saturation magnetization decreases with increasing Si content while for Fe{sub 70}Al{sub 30-x}Si{sub x} deformed alloys the saturation magnetization has a plateau in which the saturation magnetization values do not vary.

  5. Undulators at the ALS

    International Nuclear Information System (INIS)

    At Lawrence Berkeley Laboratory's (LBL) Advanced Light Source (ALS), three 4.6 m long undulators have been completed, tested and installed. A fourth is under construction. The completed undulators include two 5.0 cm period length, 89 period devices (U5.0s) which achieve a 0.85 T effective field at a 14 mm minimum gap and a 8.0 cm period length, 55 period device (U8.0) that reaches a 1.2 T effective field at a 14 mm minimum gap. The undulator under construction is a 10.0 cm period length, 43 period device (U10.0) that is designed to achieve 0.98 T at a 23 mm gap. Undulator magnetic gap variation (rms) is within 25 microns over the periodic structure length. Reproducibility of the adjustable magnetic gap has been measured to be within +/- 5 microns. Gap adjusting range is from 14 mm to 210 mm, which can be scanned in one minute. The 5.1 m long vacuum chambers are flat in the vertical direction to within 0.74 mm and straight in the horizontal direction to within 0.08 mm over the 4.6 m magnetic structure sections. Vacuum chamber base pressures after UHV beam conditioning are. in the mid 10-11 Torr range and storage ring operating pressures with full current are in the low 10-10 Torr range. Measurements show that the uncorrelated magnetic field errors are 0.23%, and 0.20% for the two U5.Os and the U8.0 respectively and that the field integrals are small over the 1 cm by 6 cm beam aperture. Device description, fabrication, and measurements are presented

  6. Alexandria (Al Iskandariya), Egypt

    Science.gov (United States)

    2002-01-01

    This image of Alexandria was taken by astronauts on board the International Space Station in December 2000 using an Electronic Still Camera. A wider-angle view (STS088-739-90) taken from the Space Shuttle in December 1998 is available for context. Alexandria (Al Iskandariya) occupies a T-shaped peninsula and strip of land separating the Mediterranean from Lake Mariout. Originally the town was built upon a mole (stone breakwater) called Heptastadium, which joined the island of Pharos (see referenced website, below) to the mainland. Since then sedimentary deposits have widened the mole. Since 1905, when the 370,000 Alexandrians lived in an area of about 4 sq km between the two harbors, the city (population 4 million; see referenced website, below) has grown beyond its medieval walls and now occupies an area of about 300 sq km. The Mahmudiya Canal, connecting Alexandria with the Nile, runs to the south of the city and, by a series of locks, enters the harbor of the principal port of Egypt (note ships). The reddish and ochre polygons west of Lake Mariout are salt-evaporation, chemical-storage, and water-treatment ponds within the coastal lagoon. Reference Youssef Halim and Fatma Abou Shouk, 2000, Human impacts on Alexandria's marine environment: UNESCO, Coastal Regions and Small Islands Unit (CSI), Coastal Management Sourcebooks 2 (accessed December 20, 2000) Additional photographs taken by astronauts can be viewed at NASA-JSC's Gateway to Astronaut Photography of Earth. Image ISS001-ESC-5025 provided by the Earth Sciences and Image Analysis Laboratory, Johnson Space Center.

  7. Proteomics Approach to the Study of Cattle Tick Adaptation to White Tailed Deer

    Directory of Open Access Journals (Sweden)

    Marina Popara

    2013-01-01

    Full Text Available Cattle ticks, Rhipicephalus (Boophilus microplus, are a serious threat to animal health and production. Some ticks feed on a single host species while others such as R. microplus infest multiple hosts. White tailed deer (WTD play a role in the maintenance and expansion of cattle tick populations. However, cattle ticks fed on WTD show lower weight and reproductive performance when compared to ticks fed on cattle, suggesting the existence of host factors that affect tick feeding and reproduction. To elucidate these factors, a proteomics approach was used to characterize tick and host proteins in R. microplus ticks fed on cattle and WTD. The results showed that R. microplus ticks fed on cattle have overrepresented tick proteins involved in blood digestion and reproduction when compared to ticks fed on WTD, while host proteins were differentially represented in ticks fed on cattle or WTD. Although a direct connection cannot be made between differentially represented tick and host proteins, these results suggested that differentially represented host proteins together with other host factors could be associated with higher R. microplus tick feeding and reproduction observed in ticks fed on cattle.

  8. Thermal Modeling of Al-Al and Al-Steel Friction Stir Spot Welding

    Science.gov (United States)

    Jedrasiak, P.; Shercliff, H. R.; Reilly, A.; McShane, G. J.; Chen, Y. C.; Wang, L.; Robson, J.; Prangnell, P.

    2016-09-01

    This paper presents a finite element thermal model for similar and dissimilar alloy friction stir spot welding (FSSW). The model is calibrated and validated using instrumented lap joints in Al-Al and Al-Fe automotive sheet alloys. The model successfully predicts the thermal histories for a range of process conditions. The resulting temperature histories are used to predict the growth of intermetallic phases at the interface in Al-Fe welds. Temperature predictions were used to study the evolution of hardness of a precipitation-hardened aluminum alloy during post-weld aging after FSSW.

  9. KWIN nu ook als app

    NARCIS (Netherlands)

    Rotgers, G.; Vermeij, I.

    2014-01-01

    KWIN, Kwantitatieve Informatie Veehouderij, verscheen de afgelopen 25 jaar als lijvig handboek, zowel op papier als digitaal. Dit najaar is daar een serie apps bij gekomen, waarmee adviseurs en veehouders zelf saldo- en kostprijsberekeningen kunnen maken. De apps zijn beschikbaar voor de pluimvee-,

  10. Philosophieren als Unterrichtsprinzip im Mathematikunterricht

    Science.gov (United States)

    Meerwaldt, Diana

    Philosophieren und Mathematik scheinen zunächst gegensätzliche Bereiche zu sein, die sich kaum vereinbaren lassen. Dies trifft für eine Auffassung zu, die Philosophieren als "Gerede" disqualifiziert und Mathematik als eine reine "Formelwissenschaft" begreift. Beide Auffassungen werden den Gegenständen nicht gerecht.

  11. El miedo al rey

    Directory of Open Access Journals (Sweden)

    François FORONDA

    2007-01-01

    Full Text Available La peur du roi. Sources et premières réflexions à propos d’une émotion aristocratique dans la Castille du XIVe siècleFace à un roi qui à présent pousse les effets de son ire jusqu’au meurtre pour faire le vide autour de lui et imposer sa différence souveraine, ses parents et les riches hommes, soit les principaux visés par cette politique de l’arbitraire qui enfreint les règles du jeu autant qu’elle contribue à les redéfinir, disent la peur (metus qu’ils ressentent, qu’ils utilisent aussi afin de donner à leur stratégie de pouvoir un fondement légitime. Et l’expression de cette émotion politique, qui tend à se muer en un stéréotype d’un discours aristocratique d’opposition, surtout présente dans les chroniques, mises ici en relation ici avec d’autres sources, notamment des correspondances, marque profondément l’histoire des relations souvent conflictuelles au sein de cette compagnie en définitive très étroite pendant un siècle, de la fin du XIIIe siècle à la fin du XIVe siècle. Cet article se propose d’ébaucher une première réflexion sur le sujet et d’en présenter les principales sources.El miedo al rey. Fuentes y primeras reflexiones acerca de una emoción aristocrática en la Castilla del siglo XIVFrente a un rey que ahora lleva hasta la muerte los efectos de su ira para hacer el vacío entorno a su persona e imponer su soberana, sus parientes y ricos hombres, o sea los principales afectados por esta política de la arbitrariedad que rompe las reglas del juego a la vez que contribuye a redefinirlas, dicen el miedo (metus que sienten, que utilizan también para darle a su estrategia de poder un fundamento legítimo. Y la expresión de esta emoción política, que tiende a convertirse en un estereotipo de un discurso aristocrático de oposición, sobre todo presente en la crónicas, aquí puestas en relación con otras fuentes, en particular cartas, marca profundamente la historia de

  12. Quantum dots formed in InSb/AlAs and AlSb/AlAs heterostructures

    Science.gov (United States)

    Abramkin, D. S.; Rumynin, K. M.; Bakarov, A. K.; Kolotovkina, D. A.; Gutakovskii, A. K.; Shamirzaev, T. S.

    2016-06-01

    The crystal structure of new self-assembled InSb/AlAs and AlSb/AlAs quantum dots grown by molecularbeam epitaxy has been investigated by transmission electron microscopy. The theoretical calculations of the energy spectrum of the quantum dots have been supplemented by the experimental data on the steady-state and time-resolved photoluminescence spectroscopy. Deposition of 1.5 ML of InSb or AlSb on the AlAs surface carried out in the regime of atomic-layer epitaxy leads to the formation of pseudomorphically strained quantum dots composed of InAlSbAs and AlSbAs alloys, respectively. The quantum dots can have the type-I and type-II energy spectra depending on the composition of the alloy. The ground hole state in the quantum dot belongs to the heavy-hole band and the localization energy of holes is much higher than that of electrons. The ground electron state in the type-I quantum dots belongs to the indirect X XY valley of the conduction band of the alloy. The ground electron state in the type-II quantum dots belongs to the indirect X valley of the conduction band of the AlAs matrix.

  13. Consoer et al PFOS dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — This ScienceHub entry was developed for the published paper: Consoer et al., 2016, Toxicokinetics of perfluorooctane sulfonate in rainow trout (Oncorhynchus...

  14. EKSKURSO AL CANGYAN-MONTO

    Institute of Scientific and Technical Information of China (English)

    Verkita; de; Li; Shijun

    1999-01-01

    La Pekina Esperanto-Asocio preskaǚ sta-rigis tradicion organizi ekskurson printempe kajaǚtune. En la pasinta jaro, ni ekskursis al In-terna Mongolio kaj habis agrablajn renkontiojnkun geesperantistoj en Huhehot kaj Baotou. i-

  15. DESAFÍOS AL ORDEN

    Directory of Open Access Journals (Sweden)

    Evangelina De los Rios

    2012-03-01

    Full Text Available Fradkin, Raúl y Gelman, Jorge (Compiladores, Desafíos al Orden. Política y sociedades rurales durante la Revolución de Independencia, Prohistoria ediciones, Rosario, 2008, 157 pp.

  16. Seltzer_et_al_2016

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset supports the modeling study of Seltzer et al. (2016) published in Atmospheric Environment. In this study, techniques typically used for future air...

  17. Information als Gegenstand von Informationskompetenz

    OpenAIRE

    Ingold, Marianne

    2011-01-01

    Der Informationsbegriff als zentraler Gegenstand von Informationskompetenz wird in der bibliothekarischen Diskussion in der Regel nicht explizit thematisiert, sondern lässt sich aus Fachliteratur und Bibliothekspraxis nur implizit erschließen. Eine theoretische Beschäftigung mit dem Informationsbegriff ist jedoch unabdingbar, soll das Konzept "Informationskompetenz" auch außerhalb des bibliothekarischen Kontextes verständlich und nutzbar gemacht werden. Im vorliegenden Text, der sich als Beit...

  18. Strain sensing with sub-micron sized Al-AlOx-Al tunnel junctions

    OpenAIRE

    Koppinen, P. J.; Lievonen, J. T.; Ahlskog, M.; Maasilta, I. J.

    2009-01-01

    We demonstrate a local strain sensing method for nanostructures based on metallic Al tunnel junctions with AlOx barriers. The junctions were fabricated on top of a thin silicon nitride membrane, which was actuated with an AFM tip attached to a stiff cantilever. A large relative change in the tunneling resistance in response to the applied strain (gauge factor) was observed, up to a value 37. This facilitates local static strain variation measurements down to ~10^{-7}.

  19. Al clamor de les vuvuzeles

    Directory of Open Access Journals (Sweden)

    Javier Olivera Betrán

    2010-09-01

    Full Text Available El Mundial de Futbol de Sud-àfrica ha situat l’Àfrica al mapa mundial i ha mostrat al món el triomf de l’estil de futbol d’Espanya basat en la col·lectivitat, l’esperit d’equip, la humilitat, la cohesió interna i el joc bonic. L’organització africana, seriosa i eficaç, ha sabut mobilitzar i il·lusionar la població del país que ha participat en el mundial des de l’orgull de ser africà, amb l’esperit alegre, festiu i també reivindicatiu de la gent de l’Àfrica. Aquest esdeveniment suposa el llançament de la marca “Sud-àfrica” al món amb un avís clar d’optar a l’organització d’uns primers Jocs Olímpics a Àfrica (potser els de 2020. S’obre una finestra d’esperança al segle xxi per al continent perdut de la mà de l’esport espectacle tan universal, massiu, emocional i mercantil que també es juga a la canxa de la política i de l’economia.

  20. A united refinement technology for commercial pure Al by Al-10Ti and Al-Ti-C master alloys

    International Nuclear Information System (INIS)

    Because flake-like TiAl3 particles in Al-Ti-C master alloys prepared in a melt reaction method dissolve slowly when they are added into Al melt at 720 deg. C, Ti atoms cannot be released rapidly to play the assistant role of grain refinement, leading to a poor refinement efficiency of Al-Ti-C master alloys. A united refinement technology by Al-10Ti and Al-Ti-C master alloys was put forward in this paper. The rational combination of fine blocky TiAl3 particles in Al-10Ti and TiC particles in Al-Ti-C can improve the nucleation rate of α-Al. It not only improves the grain refinement efficiency of Al-Ti-C master alloys, but also reduces the consumption

  1. Conjuntivitis alérgica

    Directory of Open Access Journals (Sweden)

    Alejandro Tello Hernández

    2008-07-01

    Full Text Available La conjuntivitis alérgica es una de las causas más comunesde consulta externa en oftalmología y tiene una muy altarelación con las reacciones alérgicas sistémicas. Lafisiopatología de las reacciones de hipersensibilidad noshace entender los cuadros clínicos característicos de estapatología y sus diferentes grados de severidad. Eldiagnostico diferencial es amplio, sin embargo hay clavesdiagnosticas que nos orientan rápidamente al diagnosticocorrecto. El tratamiento se enfoca en las medidasfarmacológicas y no farmacológicas, utilizándolas enconjunto para disminuir la recurrencia del cuadro y prevenirsecuelas visuales.

  2. Electrowinning Al from Al2S3 in Molten Salt

    NARCIS (Netherlands)

    Xiao, Y.; Van der Plas, D.W.; Bohte, J.; Lans, S.C.; Van Sandwijk, A.; Reuter, M.A.

    2007-01-01

    In order to investigate an alternative process for the production of primary aluminum via a sulfide intermediate, the electrochemical behavior of Al2S3 in molten salt has been studied on a laboratory scale. The effects of electrolyte composition, temperature, and cell design on the cell performance

  3. ALS:A SAIRASTAVAN TOIMINTATERAPIA

    OpenAIRE

    Vuorinen, Johanna

    2013-01-01

    Amyotrofinen lateraali skleroosi on harvinainen, etenevä sairaus. Sairaus surkastuttaa edetessään potilaan tahdonalaisen lihaksiston. Sairauden oireet näkyvät yleensä ensin raajoissa, mutta myös nielun lihaksista alkava bulbaarinen taudinmuoto on mahdollinen. ALS voi myös aiheuttaa frontotemporaalista dementiaa. Sairaus etenee yksilöllisesti, mutta sen kesto on yleensä noin 3-5 vuotta. Keski-Suomen keskussairaalassa ALS:n sairastuneen kuntoutukseen osallistuu moniammatillinen työryhmä, j...

  4. Al-Qaeda Since 911

    OpenAIRE

    Brahimi, Alia

    2012-01-01

    Seconds after smiling at her local MP and shaking his hand, Roshonara Choudhry plunged a knife into his stomach. The attack on Stephen Timms in May 2010 was not the most high profile assault inspired by al- Qaeda, nor was it fatal. It did, however, offer a commentary on the changing nature of the terrorist threat since 9/11, al-Qaeda’s major impact on international relations as well as its major failure, and the intimate, perhaps inevitable, connection between the two.

  5. Andalusian astronomy: al-Zij al-Muqtabis of Ibn al-Kammâd.

    Science.gov (United States)

    Chabás, J.; Goldstein, B. R.

    1994-12-01

    In the twelfth century the Arabic astronomer Ibn al-Kammâd, living in Islamic Spain, composed three sets of astronomical tables, called "zijes". The zijes were largely based on the work of predecessors, going back to Ptolemy on the one hand, and Hindu astronomers on the other. None of his zijes survived in the original Arabic, but a Latin manuscript contains a translation of an apparently complete zij, the "al-Zij al-Muqtabis". This paper examines the body of astronomical knowledge contained in this zij. Specifically, it is shown that one can gain valuable information on the solar theory of the Islamic astronomers from this translation. Furthermore, the theory of lunar and solar eclipses in the work is analyzed, and tables of mean planetary and solar motions are discussed. In addition, tables for the motion of the vernal equinox, star tables, and several topics of Islamic spherical astronomy are examined.

  6. ¿COLOMBIA DEBE APOSTARLE AL SOFTWARE LIBRE, AL DE FUENTE ABIERTA O AL PROPIETARIO?

    Directory of Open Access Journals (Sweden)

    Luis Alberto Girón Murillo

    2014-06-01

    Full Text Available Es complejo para gestores y administradores conocer las implicaciones que la adopción de modelos de desarrollo de software tendría para una región. Este artículo ofrece una evaluación de las implicaciones dinámicas que para el desarrollo de software de una región tendría el apostar de forma excluyente al software libre, al software de fuente abierta y al software propietario. Se desarrolló un modelo de simulación en Vensim de la dinámica de sistemas en donde se evaluaron 3 escenarios: uno en donde se adopta de forma excluyente el software libre, uno en donde se adopta el software propietario y uno en donde se adopta el software de fuente abierta. Se ofrecen descripciones y explicaciones de los resultados que sugieren las potencialidades de cada uno de los modelos de desarrollo evaluados.

  7. Dynamic Modeling of ALS Systems

    Science.gov (United States)

    Jones, Harry

    2002-01-01

    The purpose of dynamic modeling and simulation of Advanced Life Support (ALS) systems is to help design them. Static steady state systems analysis provides basic information and is necessary to guide dynamic modeling, but static analysis is not sufficient to design and compare systems. ALS systems must respond to external input variations and internal off-nominal behavior. Buffer sizing, resupply scheduling, failure response, and control system design are aspects of dynamic system design. We develop two dynamic mass flow models and use them in simulations to evaluate systems issues, optimize designs, and make system design trades. One model is of nitrogen leakage in the space station, the other is of a waste processor failure in a regenerative life support system. Most systems analyses are concerned with optimizing the cost/benefit of a system at its nominal steady-state operating point. ALS analysis must go beyond the static steady state to include dynamic system design. All life support systems exhibit behavior that varies over time. ALS systems must respond to equipment operating cycles, repair schedules, and occasional off-nominal behavior or malfunctions. Biological components, such as bioreactors, composters, and food plant growth chambers, usually have operating cycles or other complex time behavior. Buffer sizes, material stocks, and resupply rates determine dynamic system behavior and directly affect system mass and cost. Dynamic simulation is needed to avoid the extremes of costly over-design of buffers and material reserves or system failure due to insufficient buffers and lack of stored material.

  8. Un controesempio al Modus Ponens

    Directory of Open Access Journals (Sweden)

    Vann McGee

    2011-11-01

    Full Text Available La traduzione dell’articolo è stata resa possibile grazie al consenso dell’autore e del Journal of Philosophy. Riferimenti originali: Vann McGee (1985: “A Counterexample to Modus Ponens”, Journal of Philosophy, Vol. 82, No. 9 (Sep. 1985, pp. 462-47. [N.d.T.

  9. Derecho humano al agua y al saneamiento: derechos estrechamente vinculados al derecho a la vida

    OpenAIRE

    Fernández Aller, Maria Celia; Luis Romero, Elena de; Guzmán Acha, Cristina

    2013-01-01

    Los derechos humanos al agua y al saneamiento están íntimamente relacionados con otros derechos esenciales para la vida, como la alimentación o la salud. Su reconocimiento como derechos humanos en 2010 marca un hito importante en el respeto, protección y realización de estos derechos, que se encuentran seriamente vulnerados para una mayoría de población más vulnerable y empobrecida, sobre todo en el ámbito rural. Mucho camino queda aún para conseguir no sólo la disponibilidad de agua y saneam...

  10. First principles calculation of ac conductance for Al-BDT-Al and Al-Cn-Al systems

    Directory of Open Access Journals (Sweden)

    Jia-Ning Zhuang

    2011-12-01

    Full Text Available We perform first-principles calculation to investigate the dynamic conductance of atomic wires of the benzenedithiol (BDT as well as carbon chains with different length in contact with two Al(100 electrodes (Al-Cn-Al. Our calculation is based on the combination of the non-equilibrium Green's function and the density functional theory. For ac conductance, there are two theories that ensures the current conservation: (1. the global formula which is a phenomenological theory that partitions the total displacement current into each leads so that the current is conserved.(2. the local formula which is a microscopic theory that includes Coulomb interaction explicitly so that the current is conserved automatically. In this work, we use the local formula to calculate the dynamic conductance, especially the emittance. We give a detailed comparison and analysis for the results obtained from two theories. Our numerical results show that the global formula overestimates the emittance by two orders of magnitude. We also obtain an inequality showing that the emittance from global formula is greater than that from local formula for real atomic structures. For Al-Cn-Al structures, the oscillatory behavior as the number of carbon chain N varies from even to odd remains unchanged when local formula is used. However, the prediction of local formula gives rise to opposite response when N is odd (inductive-like as compared with that of global formula. Therefore, one should use the local formula for an accurate description of ac transport in nanoscale structures. In addition, the ‘size effect’ of the ac emittance is analyzed and can be understood by the kinetic inductance. Since numerical calculation using the global formula can be performed in orbital space while the local formula can only be used in real space, our numerical results indicate that the calculation using the local formula is extremely computational demanding.

  11. Personalidad y tolerancia al dolor

    Directory of Open Access Journals (Sweden)

    JESÚS M.ª CARRILLO

    2005-01-01

    Full Text Available Se examina la relación de algunas variables de personalidad -EPQ-A (Eysenck y Eysenck, 1975, NEO-PI (McCrae y Costa, 1988 y STA -personalidad esquizotípica- y STB -personalidad límite-, de Claridge y Broks (1984, con la tolerancia al dolor experimental inducido mediante agua fría (cold pressor test, según el procedimiento de Staats, Heckmat y Staats (1998 en una muestra filtrada mediante un cuestionario sobre dolor crónico, dolores de cabeza, de espalda, artritis, síndrome de Raynaud, y personas bajo medicación. La tolerancia al dolor experimental se evaluó mediante el Umbral del dolor (tiempo en segundos desde la introducción de la mano en el agua hasta el primer informe de dolor, Mantenimiento del dolor (duración en segundos de la inmersión de la mano desde la aparición del umbral hasta su retirada y Tolerancia al dolor (duración total en segundos de la inmersión de la mano desde su introducción hasta su retirada. Un análisis correlacional, factorial y de regresión por pasos mostraron un efecto cruzado entre medidas de ansiedad (tolerancia negativa al dolor y psicoticismo, siendo psicoticismo junto con control emocional predictores de tolerancia positiva al dolor. En cuanto a psicoticismo, parece que son sus elementos de naturaleza paranoide y de "dureza" los que afectan a una percepción atenuada del dolor.

  12. 76 FR 38700 - United States, et al.

    Science.gov (United States)

    2011-07-01

    ... Antitrust Division United States, et al. v. American Express Company, et al.; Public Comments and Response...), the United States hereby publishes below its Response to public comments received on the proposed Final Judgment in United States, et al. v. American Express Company, et al., Civil Action No....

  13. Large rectification magnetoresistance in nonmagnetic Al/Ge/Al heterojunctions.

    Science.gov (United States)

    Zhang, Kun; Li, Huan-Huan; Grünberg, Peter; Li, Qiang; Ye, Sheng-Tao; Tian, Yu-Feng; Yan, Shi-Shen; Lin, Zhao-Jun; Kang, Shi-Shou; Chen, Yan-Xue; Liu, Guo-Lei; Mei, Liang-Mo

    2015-09-21

    Magnetoresistance and rectification are two fundamental physical properties of heterojunctions and respectively have wide applications in spintronics devices. Being different from the well known various magnetoresistance effects, here we report a brand new large magnetoresistance that can be regarded as rectification magnetoresistance: the application of a pure small sinusoidal alternating-current to the nonmagnetic Al/Ge Schottky heterojunctions can generate a significant direct-current voltage, and this rectification voltage strongly varies with the external magnetic field. We find that the rectification magnetoresistance in Al/Ge Schottky heterojunctions is as large as 250% at room temperature, which is greatly enhanced as compared with the conventional magnetoresistance of 70%. The findings of rectification magnetoresistance open the way to the new nonmagnetic Ge-based spintronics devices of large rectification magnetoresistance at ambient temperature under the alternating-current due to the simultaneous implementation of the rectification and magnetoresistance in the same devices.

  14. Al/Au/n-Si/Al surface barrier detector

    International Nuclear Information System (INIS)

    Charged-particle detectors are required to be operated sometimes in ambient light for applications like alpha counting and range finding. Detectors like Al/p-Si surface barrier with aluminium on the front side are found quite suitable. Gold/n-Si surface barrier detectors are not usable because of their excessive background photo current. These detectors, we fabricate for use in nuclear experiments, were given an aluminium coating on their gold side for use in room light. The Au/n-Si/Al surface barrier diodes were characterized for their electrical properties and performance as alpha detectors. Detectors showing good energy resolution (∼ 50 KeV) were selected and provided with another thin reflecting coat of aluminium on their front sides

  15. Poderá o carrapato transmitir a lepra?: isolamento e cultura dum bacilo acido-álcool resistente de sedimento de "Amblyomma cajennense" capturado em leproso: 2ª nota May ticks transmit leprosy?: Second Note

    Directory of Open Access Journals (Sweden)

    H. C. Souza-Araujo

    1942-01-01

    Full Text Available In this 2nd note upon the possibility of transmission of human leprosy by ticks, the A. relates his stepps to obtain the collaboration of his colleagues working in leprosaria in various States of Brazil, Argentina and Paraguay in such studies. Firstly the A. describes the positive results of examination of sediment of ticks, the cattle tick Boophilus microplus (Canestrini, 1888, received from Paraná (Leprosário São Roque , which were put on active lepers, two of them sucking during 9 days and one during 7 days. Two out of three were killed for examination and were very strongly positive for acid-fast bacilli. A series of tubes of Loewenstein medium was smeared with the sediment of such ticks. Secondly the A. relates his personnal experiment, carried out in Rio de Janeiro, trying to infect normal ticks in lepers. The experiment with Boophilus microplus was negative and was twicely positive the experiment with Amblyomma cajennense Fabricius, 1794. The experiment is being in progress and will be continued in other places of Brazil. Finally, after being given the general characteristics of Boophilus microplus, the A. describes the non-chromogenic culture of a acid-fast bacillus isolated by him from sediment of ticks (Amblyomma cajennense captured in lepers from Colônia Santa Isabel (Minas gerais, which parasitism was spontaneous. The first isolation was obtained in Loewenstein medium after 62 days incubation at 37°C. The culture is pure and the bacillus is permanent acid-fast. The plate1, in full color, represents this culture in its four generations. The colonies are pearl-white in color, dry, elevated and rough, developing slowly and beginning as white pinhead points scattered upon the surface of the medium. The culture is not yet rich enough to be inoculated into laboratory animals, which will be done when possible.

  16. Tick cell lines for study of Crimean-Congo hemorrhagic fever virus and other arboviruses.

    Science.gov (United States)

    Bell-Sakyi, Lesley; Kohl, Alain; Bente, Dennis A; Fazakerley, John K

    2012-09-01

    Continuous cell lines derived from many of the vectors of tick-borne arboviruses of medical and veterinary importance are now available. Their role as tools in arbovirus research to date is reviewed and their potential application in studies of tick cell responses to virus infection is explored, by comparison with recent progress in understanding mosquito immunity to arbovirus infection. A preliminary study of propagation of the human pathogen Crimean-Congo hemorrhagic fever virus (CCHFV) in tick cell lines is reported; CCHFV replicated in seven cell lines derived from the ticks Hyalomma anatolicum (a known vector), Amblyomma variegatum, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus (Boophilus) microplus, and Ixodes ricinus, but not in three cell lines derived from Rhipicephalus appendiculatus and Ornithodoros moubata. This indicates that tick cell lines can be used to study growth of CCHFV in arthropod cells and that there may be species-specific restriction in permissive CCHFV infection at the cellular level.

  17. Report on ticks collected in the Southeast and Mid-West regions of Brazil: analyzing the potential transmission of tick-borne pathogens to man

    Directory of Open Access Journals (Sweden)

    Figueiredo Luiz Tadeu Moraes

    1999-01-01

    Full Text Available Specimens of ticks were collected in 1993, 1996, 1997, and 1998, mostly from wild and domestic animals in the Southeast and Mid-West regions of Brazil. Nine species of Amblyommidae were identified: Anocentor nitens, Amblyomma cajennense, Amblyomma ovale, Amblyomma fulvum, Amblyomma striatum, Amblyomma rotundatum, Boophilus microplus, Boophilus annulatus, and Rhipicephalus sanguineus. The potential of these tick species as transmitters of pathogens to man was analyzed. A Flaviviridade Flavivirus was isolated from Amblyomma cajennense specimens collected from a sick capybara (Hydrochaeris hydrochaeris. Amblyomma cajennense is the main transmitter of Rickettsia rickettsii (=R. rickettsi, the causative agent of spotted fever in Brazil. Wild mammals, mainly capybaras and deer, infested by ticks and living in close contact with cattle, horses and dogs, offer the risk of transmission of wild zoonosis to these domestic animals and to man.

  18. Al-Anon and recovery.

    Science.gov (United States)

    Cermak, T L

    1989-01-01

    The history of Al-Anon and its current demographics are reviewed. In order to understand 12-step recovery and psychotherapy for family members of alcoholics, the concept of codependence is defined with a set of diagnostic criteria consistent with the DSM-III-R definition of personality traits and disorders. At the core of codependence are denial and an unrealistic relationship to willpower. The therapeutic implications of considering codependence as a personality disorder are explored, as are the characteristics that make codependence unique among personality disorders: the central role of denial and the existence of a self-help organization to facilitate recovery. The dynamics of working the 12 steps on codependent characteristics are outlined. A synergistic relationship between psychotherapy and the 12 steps is described. Special attention is given the emergence of Al-Anon adult children of alcoholic meetings, and the future of codependence is discussed.

  19. Sui controesempi al Modus Ponens

    Directory of Open Access Journals (Sweden)

    Giorgio Sbardolini

    2011-11-01

    Full Text Available In McGee (1985 si presentano tre controesempi al modus ponens (MP, e si argomenta di come esistano restrizioni alla validità di questa regola deduttiva. Nel presente articolo, intendo ridiscutere questi tre controesempi a MP mostrando perché non colgono il bersaglio, e presentare altri casi in cui l'applicazione di MP non sembra efficace.In [McGee, 1985] si presentano 3 controesempi al modus ponens (MP, e si argomenta di come esistano restrizioni alla validità di questa regola deduttiva. Nel presente articolo, intendo ridiscutere questi 3 controesempi a MP mostrando perché non colgono il bersaglio, e presentare altri casi in cui l'applicazione di MP non sembra efficace.

  20. Al Margen de las Cooperativas

    Directory of Open Access Journals (Sweden)

    Gutiérrez Estrada Julio

    1941-04-01

    Full Text Available El sistema Cooperativista, propiamente hablando, no viene a constituir una doctrina económica, es más bien una práctica, un modo de proceder en provecho de determinada agrupación de individuos que se asocian para defenderse de la usura del comercio y del intermediarismo parasitario. "El movimiento cooperativo es tan viejo como la revolución industrial, y ha crecido paralelamente a ella, podría decirse como una protesta en contra del sistema capitalista industrial. Generalmente se considera que tres principios fundamentales determinan su carácter distintivo. 1-Se esfuerza por dar "servido al costo" a sus miembros antes que beneficiarse del negocio con el público en general. El servicio de un grupo organizado se considera como un medio para obtener el máximum de eficacia con mínimo de desperdicio. 2-Insiste en que los beneficios pecuniarios se distribuyan al miembro como productor, después de deducir solamente el interés del capital al tipo que compite, y los salarios y jornales de los trabajadores. 3-Mantiene el control democrático del negocio por todos los participantes en él".

  1. Vormundschaftsrecht als Grundlage politischer Herrschaft

    Directory of Open Access Journals (Sweden)

    Arne Duncker

    2006-07-01

    Full Text Available In ihrer beachtlichen und sehr gewissenhaft dokumentierten Arbeit über vormundschaftliche Regentschaften im 16. und 17. Jahrhundert beschreibt Pauline Puppel unter ausführlichem Bezug auf zeitgenössische Literatur und Archivalien sowohl die allgemeine Rechtslage im damaligen Reich als auch die Anwendungsfälle in Hessen, wo zwischen 1500 und 1700 insgesamt viermal eine Landgräfin als Vormünderin des Fürsten zur Regentin ihres Landes wurde. Dies steht exemplarisch für eine bereits in der Frühen Neuzeit mögliche und nicht einmal ganz seltene Form politischer Frauenherrschaft, die bisher oft nicht hinreichend gewürdigt wurde. Puppels Untersuchung ist in zwei Hauptteile gegliedert. Der erste Teil (Das juristische Regelwerk“, S. 34-143 behandelt die zeitgenössischen Rahmenbedingungen der durch Frauen ausgeübten Vormundschaft und Regentschaft. Der zweite Abschnitt („Die Landgräfinnen von Hessen als Regentinnen“, S. 144-307 befasst sich mit der Ausfüllung dieser Regeln durch konkrete Fallbeispiele in Gestalt von Leben und Regentschaft der regierenden Landgräfinnen von Hessen.

  2. Prevalência de carrapatos em cães de áreas rurais da região norte do Estado do Paraná Prevalence of ticks on dogs from rural areas at northern region of Paraná

    OpenAIRE

    Labruna, M. B.; S.L.P. Souza; J.S. Guimarães Jr.; R.C. Pacheco; Pinter, A; Gennari, S.M.

    2001-01-01

    During January and February, 2000, 133 dogs from 21 farms located in eight diferent counties at the northern region of Paraná, Brazil, were examined for ticks. Ticks found on dogs were collected and identified. Information about dog rearing system was also obtained. Fifty-five ticks were collected on 19 dogs (14.3%) from 11 farms (52.4%). Four species were identified: Rhipicephalus sanguineus (20 ticks on nine dogs from seven farms), Boophilus microplus (15 ticks on five dogs from five farms)...

  3. Efeito do óleo de eucalipto (Corymbia citriodora) no controle do carrapato bovino Effect of eucalyptus oil (Corymbia citriodora) on the control of cattle ticks

    OpenAIRE

    Clair Jorge Olivo; Carlos Alberto Agnolin; Carla Lieda Cezimbra Parra; Fernanda Silveira Flores Vogel; Neila Silvia Pereira dos Santos Richards; Luiz Gustavo de Pellegrini; Augusto Webe; Felipe Pivoto; Luciana Araujo

    2013-01-01

    Esta pesquisa foi conduzida com o objetivo de avaliar o efeito in vitro e in vivo do óleo de eucalipto (Corymbia citriodora) sobre o carrapato bovino (Rhipicephalus (Boophilus) microplus). Na experimentação in vitro, foi utilizado o grupo controle negativo e oito concentrações de óleo de eucalipto (0,5; 1; 2; 5; 10; 20; 50; 100%), em fêmeas ingurgitadas de carrapato. A eficácia de controle foi de 0; 30,5; 75,5; 91; 100; 100; 100; 100 e 100%, respectivamente. Para a experimentação in vivo, for...

  4. Large-scale production in Pichia pastoris of the recombinant vaccine Gavac against cattle tick.

    Science.gov (United States)

    Canales, M; Enríquez, A; Ramos, E; Cabrera, D; Dandie, H; Soto, A; Falcón, V; Rodríguez, M; de la Fuente, J

    1997-03-01

    A gene coding for the Bm86 tick protein was recently cloned, expressed in Pichia pastoris and shown to induce an inmunological response in cattle against ticks. Moreover, the Gavac vaccine (Heber Biotec S.A., Havana, Cuba), which contains this recombinant protein, has proved to control the Boophilus microplus populations under field conditions. This paper reviews the development and large-scale production of this vaccine, the efficacy of the resulting product and the strategy followed in designing its production plant. The production plant fulfills biosafety requirements and GMP. PMID:9141213

  5. Desarrollo de vacunas para el control de garrapatas.

    OpenAIRE

    Canales García-Menocal, Mario Manuel

    2010-01-01

    Las garrapatas Rhipicephalus (Boophilus) spp. afectan a la ganadería de los países de zonas tropicales y subtropicales provocando perdidas millonarias a la industria. Los métodos de control para combatirlas emplean baños garrapaticidas que contaminan el medio ambiente, la carne y la leche, y seleccionan garrapatas cada vez más resistentes. La vacunación, empleando la proteína rBm86 aislada del intestino de Rhipicephalus microplus como antígeno, controló eficazmente infestaciones por R. microp...

  6. Isotermas de adsorción y cinética de secado de ciertas hortalizas y aromáticas cultivadas en Misiones

    OpenAIRE

    S. V García; M.E Schmalko; A. Tanzariello

    2007-01-01

    Se realizó un estudio para conocer los acaricidas y las técnicas de aplicación utilizadas para el control de Rhipicephalus (Boophilus) microplus en el área favorable o intermedia para el desarrollo de esta garrapata del vacuno. Para ello se efectuaron 438 encuestas en establecimientos ganaderos del norte argentino donde se constató que el 81,5% de los establecimientos destinados a la producción bovina se dedican a la actividad de cría y el resto a la invernada o ciclo completo. Los acaricidas...

  7. Evidence of a tick RNAi pathway by comparative genomics and reverse genetics screen of targets with known loss-of-function phenotypes in Drosophila

    Directory of Open Access Journals (Sweden)

    Kurscheid Sebastian

    2009-03-01

    Full Text Available Abstract Background The Arthropods are a diverse group of organisms including Chelicerata (ticks, mites, spiders, Crustacea (crabs, shrimps, and Insecta (flies, mosquitoes, beetles, silkworm. The cattle tick, Rhipicephalus (Boophilus microplus, is an economically significant ectoparasite of cattle affecting cattle industries world wide. With the availability of sequence reads from the first Chelicerate genome project (the Ixodes scapularis tick and extensive R. microplus ESTs, we investigated evidence for putative RNAi proteins and studied RNA interference in tick cell cultures and adult female ticks targeting Drosophila homologues with known cell viability phenotype. Results We screened 13,643 R. microplus ESTs and I. scapularis genome reads to identify RNAi related proteins in ticks. Our analysis identified 31 RNAi proteins including a putative tick Dicer, RISC associated (Ago-2 and FMRp, RNA dependent RNA polymerase (EGO-1 and 23 homologues implicated in dsRNA uptake and processing. We selected 10 R. microplus ESTs with >80% similarity to D. melanogaster proteins associated with cell viability for RNAi functional screens in both BME26 R. microplus embryonic cells and female ticks in vivo. Only genes associated with proteasomes had an effect on cell viability in vitro. In vivo RNAi showed that 9 genes had significant effects either causing lethality or impairing egg laying. Conclusion We have identified key RNAi-related proteins in ticks and along with our loss-of-function studies support a functional RNAi pathway in R. microplus. Our preliminary studies indicate that tick RNAi pathways may differ from that of other Arthropods such as insects.

  8. Microstructure of interaction interface between Al-Si, Zn-Al alloys and Al2O3p/6061Al composite

    Institute of Scientific and Technical Information of China (English)

    许志武; 闫久春; 吕世雄; 杨士勤

    2004-01-01

    Interaction behaviors between Al-Si, Zn-AI alloys and Al2O3p/6061AI composite at different heating temperatures were investigated. It is found that Al2O3p/6061Al composite can be wetted well by AlSi-1, AlSi-4 and Zn-Al alloys and an interaction layer forms between the alloy and composite during interaction. Little Al-Si alloys remain on the surface when they fully wet the composite and Si element in Al-Si alloy diffuses into composite entirely and assembles in the composite near the interface of Al-Si alloy/composite to form a Si-rich zone. The microstructure in interaction layer with Si penetration is still dense. Much more residual Zn-Al alloy exists on the surface of composite when it wets the composite, and porosities appear at the interface of Zn-Al alloy/composite. The penetration of elements Zn, Cu of Zn-Al alloy into composite leads to the generation of shrinkage cavities in the interaction layer and makes the microstructure of Al2 O3p/6061A1 composite loose.

  9. Armaflex in Burj al Arab; Armaflex im Burj al Arab

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, B.

    2003-07-01

    This article describes the Burj al Arab in Dubai, the unique seven-star high-rise hotel. The construction of the hotel, that is built on 250 piles driven into the sand of an artificial island in the Persian Gulf, is described. In particular, various special materials used in the building are described, as are the luxurious fittings and furnishings of the hotel. The cooling and air-conditioning installations that are necessary as a result of the desert climate of Dubai are described and the use of 'Armaflex' elastomer insulating material for the insulation of refrigeration machines and cold-water piping is discussed.

  10. Memahami Tasawuf Ibnuu Arabi dan Ibnuu al Farid: Konsep al Hubb Illahi, Wahdat al Wujud, Wahdah al Syuhud dan Wahdat al Adyan

    Directory of Open Access Journals (Sweden)

    Muhammad Robith Fuadi

    2013-12-01

    Full Text Available Kaum sufi menapaki jalan yang berbeda untuk menuju hakikat, mereka tidak menggunakan akal dan rasio untuk sampai pada hakikat. Akan tetapi, akal bukan satu-satunya jalan untuk menuju hakikat. Karena kita sering melihat sesuatu yang di luar jangkauan akal dalam hidup ini. Jalan yang ditempuh kaum sufi untuk menuju hakikat seperti kasyf, dzauq, 'iyan, musyahadah dan sebagainya dinilai sebagai sesuatu yang samar, tidak mempunyai batasan dan kaidah pasti, bahkan sering kali bercampur dengan igauan, mimpi, khayalan dan angan-angan. Tapi yang perlu kita ingat adalah bahwa media-media tersebut telah mampu menuntun manusia untuk memecahkan sesuatu yang tidak bisa dipecahkan oleh akal dan hukum-hukum fisika. Tulisan ini akan mengkaji gagasan-gagasan dua tokoh tasawuf besar yaitu Ibnu Arabi dan Ibnu al-Farid yang hidup  pada abad keenam dan ketujuh Hijriah. Tulisan ini secara spesifik akan mengkaji tiga gagasan penting ke dua tokoh tersebut. Yaitu al hubb al Ilahi, wahdat al Wujud dan wahdat al adyan.

  11. Control of tick infestations in cattle vaccinated with bacterial membranes containing surface-exposed tick protective antigens.

    Science.gov (United States)

    Almazán, Consuelo; Moreno-Cantú, Orlando; Moreno-Cid, Juan A; Galindo, Ruth C; Canales, Mario; Villar, Margarita; de la Fuente, José

    2012-01-01

    Vaccines containing the Rhipicephalus (Boophilus) microplus BM86 and BM95 antigens protect cattle against tick infestations. Tick subolesin (SUB), elongation factor 1a (EF1a) and ubiquitin (UBQ) are new candidate protective antigens for the control of cattle tick infestations. Previous studies showed that R. microplus BM95 immunogenic peptides fused to the Anaplasma marginale major surface protein (MSP) 1a N-terminal region (BM95-MSP1a) for presentation on the Escherichia coli membrane were protective against R. microplus infestations in rabbits. In this study, we extended these results by expressing SUB-MSP1a, EF1a-MSP1a and UBQ-MSP1a fusion proteins on the E. coli membrane using this system and demonstrating that bacterial membranes containing the chimeric proteins BM95-MSP1a and SUB-MSP1a were protective (>60% vaccine efficacy) against experimental R. microplus and Rhipicephalus annulatus infestations in cattle. This system provides a novel, simple and cost-effective approach for the production of tick protective antigens by surface display of antigenic protein chimera on the E. coli membrane and demonstrates the possibility of using recombinant bacterial membrane fractions in vaccine preparations to protect cattle against tick infestations. PMID:22085549

  12. Epidemiologia e controle da tristeza parasitária bovina na região sudeste do Brasil Epidemiology and control of bovine babesiosis and anaplasmosis in Southeast region of Brazil

    Directory of Open Access Journals (Sweden)

    Patrícia Macêdo Gonçalves

    2000-03-01

    Full Text Available A babesiose bovina e a anaplasmose (Tristeza Parasitária Bovina são enfermidades transmitidas pelo carrapato Boophilus microplus e por moscas hematófagas, respectivamente, ocorrendo em caráter endêmico no Brasil, acarretando elevadas perdas econômicas na pecuária. Nesse país, observa-se uma grande variedade de fatores epidemiológicos influenciando sua ocorrência, tais como: variação climática, práticas de manejo, controle de carrapato e introdução de bovinos susceptíveis. Assim, esta revisão aborda aspectos epidemiológicos do controle da anaplasmose e da babesiose bovina do Brasil, com ênfase na região sudeste. Fatores que influenciam a instabilidade e a estabilidade enzoótica de ambas as espécies também são discutidos. As medidas de controle empregadas atualmente são: quimioprofilaxia, o uso de acaricidas para o controle do carrapato vetor B. microplus, a premunição e a vacinação.Bovine babesiosis and anaplasmosis are diseases transmitted by Boophilus microplus and haematophagous diptera, respectively, occurring in endemic character in Brazil, resulting in high economic loss on livestock production. In this country a wide range of epidemiological factors influencing their occurrence, such as climate variations, husbandry practices, tick control and susceptible purebreed cattle that are regularly imported to upgrade local stocks have been described. This review focuses the epidemiological control and some aspects of bovine babesiosis and anaplasmosis in Brazil, with emphasis in southeast region. Factors influencing enzootic stability and instability of both species are also discussed. The control measures employed at present are chemoprophylaxis, use of acaricides for B. microplus, premunition and vaccination.

  13. Cold storage and cryopreservation of tick cell lines

    Directory of Open Access Journals (Sweden)

    Lallinger Gertrud

    2010-04-01

    Full Text Available Abstract Background Tick cell lines are now available from fifteen ixodid and argasid species of medical and veterinary importance. However, some tick cell lines can be difficult to cryopreserve, and improved protocols for short- and long-term low temperature storage will greatly enhance their use as tools in tick and tick-borne pathogen research. In the present study, different protocols were evaluated for cold storage and cryopreservation of tick cell lines derived from Rhipicephalus (Boophilus decoloratus, Rhipicephalus (Boophilus microplus, Ixodes ricinus and Ixodes scapularis. For short-term cold storage, cells were kept under refrigeration at 6°C for 15, 30 and 45 days. For cryopreservation in liquid nitrogen, use of a sucrose-phosphate-glutamate freezing buffer (SPG as cryoprotectant was compared with dimethylsulfoxide (DMSO supplemented with sucrose. Cell viability was determined by the trypan blue exclusion test and cell morphology was evaluated in Giemsa-stained cytocentrifuge smears. Results Cold storage at 6°C for up to 30 days was successful in preserving R. (B. microplus, R. (B. decoloratus, I. ricinus and I. scapularis cell lines; lines from the latter three species could be easily re-cultivated after 45 days under refrigeration. While cell lines from all four tick species cryopreserved with 6% DMSO were successfully resuscitated, the R. (B. decoloratus cells did not survive freezing in SPG and of the other three species, only the R. (B. microplus cells resumed growth during the observation period. Conclusions This constitutes the first report on successful short-term refrigeration of cells derived from R. (B. decoloratus, R. (B. microplus, and I. ricinus, and use of SPG as an alternative to DMSO for cryopreservation, thus making an important contribution to more reliable and convenient tick cell culture maintenance.

  14. Electrical conductivity of (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 melts

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The effects of contents of AlF3 and Al2O3,and temperature on electrical conductivity of (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 were studied by continuously varying cell constant (CVCC) technique.The results show that the conductivities of melts increase with the increase of temperature,but by different extents.Every increasing 10 ℃ results in an increase of 1.85×10-2,1.86×10-2,1.89×10-2 and 2.20×10-2 S/cm in conductivity for the (Na3AlF6-40%K3AlF6)-AlF3 melts containing 0%,20%,24%,and 30% AlF3,respectively.An increase of every 10 ℃ in temperature results an increase about 1.89×10-2,1.94×10-2,1.95×10-2,1.99×10-2 and 2.10×10-2 S/cm for (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 melts containing 0%,1%,2%,3% and 4% A12O3,respectively.The activation energy of conductance was calculated based on Arrhenius equation.Every increasing 1% of AlF3 results in a decrease of 0.019 and 0.020 S/cm in conductivity for (Na3AlF6-40%K3AlF6)-AIF3 melts at 900 and 1 000 ℃,respectively.Every increase of 1% Al2O3 results in a decrease of 0.07 S/cm in conductivity for (Na3AlF6-40%K3AlF6)-AlF3-Al2O3 melts.The activation energy of conductance increases with the increase in content of AlF3 and Al2O3.

  15. United modification of Al-24Si alloy by Al-P and Al-Ti-C master alloys

    Institute of Scientific and Technical Information of China (English)

    韩延峰; 刘相法; 王海梅; 王振卿; 边秀房; 张均艳

    2003-01-01

    The modification effect of a new type of Al-P master alloy on Al-24Si alloys was investigated. It is foundthat excellent modification effect can be obtained by the addition of this new type of A1-P master alloy into Al-24Simelt and the average primary Si grain size is decreased below 47 μm from original 225 μm. It is also found that theTiC particles in the melt coming from Al8Ti2C can improve the modification effect of the Al-P master alloy. Whenthe content of TiC particles in the Al-24Si melt is 0.03 %, the improvement reaches the maximum and keeps steadywith increasing content of TiC particles. Modification effect occurs at 50 min after the addition of the Al-P master al-loy and TiC particles, and keeps stable with prolonging holding time.

  16. Ce对Al-Si-Cu合金中α(Al)-Al2Cu共晶形貌的影响%Effect of Ce on morphology ofα(Al)-Al2Cu eutectic in Al-Si-Cu alloy

    Institute of Scientific and Technical Information of China (English)

    Maja VONINA; Joef MEDVED; Tonica BONINA; Franc ZUPANI

    2014-01-01

    The effect of Ce addition on the morphology of the α(Al)-Al2Cu eutectic in Al-Si-Cu alloy was investigated using thermal analysis, light microscopy, scanning electron microscopy, focused ion beam and energy dispersive analysis. The results show that the eutectic α(Al)-Al2Cu forms within small space between dendrites, silicon and AlSiFeMn plates. Eutectic Al2Cu is not lamellar but degenerated. However, Al2Cu in Ce-modified alloys is more compact. Ce partially dissolves in Al2Cu, which is a viable reason for the formation of coarser Al2Cu. The addition of Ce also increases the microhardness of theα(Al)-Al2Cu eutectic by almost 10%compared with the basic Al-Si-Cu alloy.%采用热分析、光学显微镜技术、扫描电镜技术、聚焦离子束和能量色散谱分析方法研究Ce对Al-Si-Cu合金中α(Al)-Al2Cu共晶形貌的影响。结果表明,在枝晶、硅和AlSiFeMn之间较小空间内形成了α(Al)-Al2Cu共晶。Al2Cu为非层状的不规则共晶组织。Al2Cu在经Ce改性的合金中更加致密。部分Ce溶解于Al2Cu中,这是粗晶Al2Cu形成的原因。与基体Al-Si-Cu合金相比,Ce的加入能使α(Al)-Al2Cu共晶合金的显微硬度提高约10%。

  17. Reply to Pachai et al.

    Science.gov (United States)

    Harrison, William J; Bex, Peter J

    2016-05-01

    Peripheral vision is fundamentally limited by the spacing between objects. When asked to report a target's identity, observers make erroneous reports that sometimes match the identity of a nearby distractor and sometimes match a combination of target and distractor features. The classification of these errors has previously been used to support competing 'substitution' [1] or 'averaging' [2] models of the phenomenon known as 'visual crowding'. We recently proposed a single model in which both classes of error occur because observers make their reports by sampling from a biologically-plausible population of weighted responses within a region of space around the target [3]. It is critical to note that there is no probabilistic substitution or averaging process in our model; instead, we argue that neither substitution nor averaging occur, but that these are misclassifications of the distribution of reports that emerge when a population response distribution is sampled. This is a fundamentally different way of thinking about crowding, and on this basis we claim to have provided a mechanism unifying categorically distinct perceptual errors. Our goal was not to model all crowding phenomena, such as the release from crowding when target and flanks differ in color or depth [4]. Pachai et al.[5] have suggested that our model is not unifying because it inaccurately predicts perceptual performance for a particular stimulus. Although we agree that our model does not predict their data, this specific demonstration overlooks the critical aspect of the model: perceptual reports are drawn from a weighted population code. We show that Pachai et al.'s [5] own data actually provide evidence for the population code we have described [3], and we suggest a biologically-plausible analysis of their stimuli that provides a computational basis for their 'grouping' account of crowding.

  18. Reply to Pachai et al.

    Science.gov (United States)

    Harrison, William J; Bex, Peter J

    2016-05-01

    Peripheral vision is fundamentally limited by the spacing between objects. When asked to report a target's identity, observers make erroneous reports that sometimes match the identity of a nearby distractor and sometimes match a combination of target and distractor features. The classification of these errors has previously been used to support competing 'substitution' [1] or 'averaging' [2] models of the phenomenon known as 'visual crowding'. We recently proposed a single model in which both classes of error occur because observers make their reports by sampling from a biologically-plausible population of weighted responses within a region of space around the target [3]. It is critical to note that there is no probabilistic substitution or averaging process in our model; instead, we argue that neither substitution nor averaging occur, but that these are misclassifications of the distribution of reports that emerge when a population response distribution is sampled. This is a fundamentally different way of thinking about crowding, and on this basis we claim to have provided a mechanism unifying categorically distinct perceptual errors. Our goal was not to model all crowding phenomena, such as the release from crowding when target and flanks differ in color or depth [4]. Pachai et al.[5] have suggested that our model is not unifying because it inaccurately predicts perceptual performance for a particular stimulus. Although we agree that our model does not predict their data, this specific demonstration overlooks the critical aspect of the model: perceptual reports are drawn from a weighted population code. We show that Pachai et al.'s [5] own data actually provide evidence for the population code we have described [3], and we suggest a biologically-plausible analysis of their stimuli that provides a computational basis for their 'grouping' account of crowding. PMID:27166690

  19. The Al-Al3Ni Eutectic Reaction: Crystallography and Mechanism of Formation

    Science.gov (United States)

    Fan, Yangyang; Makhlouf, Makhlouf M.

    2015-09-01

    The characteristics of the Al-Al3Ni eutectic structure are examined with emphasis on its morphology and crystallography. Based on these examinations, the mechanism of formation of this technologically important eutectic is postulated. It is found that a thin shell of α-Al forms coherently around each Al3Ni fiber. The excellent thermal stability of the Al-Al3Ni eutectic may be attributed to the presence of this coherent layer.

  20. Formaline of alternatieven als ontsmettingsmiddel voor broedeieren

    OpenAIRE

    Meijerhof, R.; Dijk, D. van

    1997-01-01

    Formaline wordt algemeen gezien als een goed middel om broedeieren te ontsmetten. Toch geeft ontsmetting met middelen als ozon en waterstofperoxyde vaak een iets beter broedresultaat. Een eventuele verklaring hiervoor is momenteel nog niet te geven.

  1. Grainreifnementlimit of commercialpureAl inoculatedbyAl-Ti-C(B)masteralloys

    Institute of Scientific and Technical Information of China (English)

    En-zhao Wang; Xiang-fa Liu

    2015-01-01

    The grain reifnement limits of commercial pure Al inoculated by Al-5Ti-1B, Al-5Ti-0.25C and Al-5Ti-0.3C-0.2B master al oys were studied, and the inlfuence of melting temperature on the grain reifning performance of these three master al oys was investigated using a high scope video microscope (HSVM), a ifeld-emission scanning electron microscope (FESEM), an electron probe micro-analyzer (EPMA) and X–ray diffraction (XRD) method. Results show that there is a grain reifnement limit of commercial pure Al reifned by these three master al oys; with the same addition level of 1.5% under the present experimental conditions, the grain reifnement limits (smal est average grain size) of commercial pure Al reifned by Al-5Ti-1B, Al-5Ti-0.25C and Al-5Ti-0.3C-0.2B master al oys are 50 µm, 80 µm and 80 µm, respectively. In addition, with an increase in the melting temperature of the pure Al, the grain reifning performance of Al-5Ti-1B and Al-5Ti-0.25C master al oys decreases, but the grain reifning performance of Al-5Ti-0.3C-0.2B changes little.

  2. Betaalde arbeid als verdringer van vrijwilligerswerk? Overbelasting als mogelijke verklaring

    Directory of Open Access Journals (Sweden)

    Angela Kok-Van Meer

    2014-06-01

    Full Text Available Do paid work activities displace volunteering? A potential explanation from role overload theoryRecent changes in Dutch society might lead to a shortage of volunteers. On the one hand, the demand for volunteers is increasing: in the social welfare domain because of governmental austerity policies and in other domains such as sports because of the higher supervision intensity of activities. On the other hand, the supply of volunteers is likely to decrease as more and more women and older workers are active in the labor market, which reduces the time that is available for volunteering. Role overload theory would suggest that the increasing labor participation rate of certain categories of workers goes along with a decline of participation in voluntary work. The secondary data analysis shows that various role loads (work, care for children living at home are associated with differences in participation in voluntary work. However, while a higher number of contractual work hours and hours spent on work-related training are negatively associated with volunteer work, care for children living at home is positively associated with volunteering. These results provide only limited support for role overload theory.Betaalde arbeid als verdringer van vrijwilligerswerk? Overbelasting als mogelijke verklaringDe afgelopen jaren hebben zich enkele maatschappelijke veranderingen voorgedaan, die wellicht tot schaarste op de Nederlandse vrijwilligersmarkt zouden kunnen leiden. Enerzijds neemt de vraag naar vrijwilligers toe doordat subsidieregelingen versoberen (bijvoorbeeld in zorg en welzijn en de begeleidingsintensiteit in bepaalde organisaties stijgt (bijvoorbeeld in sport. Anderzijds neemt het aanbod van vrijwilligers af doordat vrouwen en ouderen meer en langer op de arbeidsmarkt actief zijn, waardoor minder tijd beschikbaar is voor vrijwilligerswerk. In dit artikel wordt aan de hand van de role overload theorie nagegaan of het al dan niet deelnemen aan

  3. AlON-SiAlON复合材料的制备及特性%Preparation and properties of AlON-SiAlON composites

    Institute of Scientific and Technical Information of China (English)

    山下敬; 山口明良

    2003-01-01

    为提高AlON陶瓷材料的抗氧化性能,制备了AlON-SiAl7O2N7复相材料.在1750℃、0.5 MPa的N2气氛中,保温2 h烧成不同Al2O3/AlN/Si3N4配比的原料得到不同AlON/SiAl7O2N7比的复相材料.因为在烧结SiAl7O2N7的过程中,蒸发-凝聚的同时伴随着SiO气体的挥发,因此很难得到致密的AlON-SiAl7O2N7复相材料.研究了AlON-SiAl7O2N7复相材料在1300℃、空气中的抗氧化性能,同时作为比较,研究了相同条件下单相的AlON材料的抗氧化性能.结果表明,AlON-SiAl7O2N7复相材料显示了较之单相的AlON陶瓷材料更好的抗氧化性能,这是因为氧化过程中所形成的含玻璃相的表面氧化层抑制了氧的向内扩散所致.

  4. con bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Adriana Mora Antó

    2005-01-01

    Full Text Available Esta investigación dio cuenta de la relación entre el estilo de funcionamiento familiar, los patrones de crianza y las edades de desarrollo evolutivo en niños, nacidos con bajo peso. El estudio descriptivo correlacional se realizó con 41 niños y sus madres, aplicándose cuestionarios sobre funcionamiento familiar, prácticas de crianza y desarrollo infantil. Los resultados señalaron la existencia de un funcionamiento familiar caracterizado por una cohesión amalgamada y una adaptabilidad caótica, una disciplina complaciente, falta de control y de límites claros en la díada madre-hijo. Se trataba de familias monoparentales, donde la temprana edad de concepción, el madresolterismo y el apoyo de la familia extensa eran constantes. Las edades evolutivas registradas indicaron un desarrollo inferior a la edad cronológica, en la mayor parte de los casos; sin embargo, éstas tendieron a ser superiores al compararlas con la edades reales de los infantes. No se encontró una correlación estadísticamente significativa entre la edad de desarrollo y los diferentes factores del funcionamiento familiar para algunos de los rangos de edad considerados; sin embargo, no se lo descartó por completo, especialmente en lo referente al optimismo familiar

  5. Topiramat als Phasenprophylaktikum - ein Fallbericht

    Directory of Open Access Journals (Sweden)

    Letmaier M

    2001-01-01

    Full Text Available Topiramat ist ein neues Antiepileptikum mit einem breiten Wirkspektrum. Aktuelle klinische Studien geben Hinweise darauf, daß Topiramat stimmungsstabilisierende Eigenschaften besitzt und somit effizient in der Behandlung der bipolaren affektiven Störung sein könnte. Vor dem Hintergrund dieser Studienberichte, behandelten wir eine 41jährige, erstmals vor 10 Jahren erkrankte Patientin mit der Diagnose einer therapierefraktären, bipolaren affektiven Störung (Rapid-Cycling mit Topiramat. Im Rahmen ihrer Erkrankung wurde die Patientin insgesamt 12mal stationär aufgenommen und meist aufgrund von akuten manischen Episoden behandelt. Dabei kamen seit 1991 folgende Phasenprophylaktika zur Anwendung: Carbamazepin, Valproat und Lamotrigin ? zuletzt nur mit mäßigem Erfolg. Daraufhin wurde zu Beginn einer neuerlichen manischen Episode ambulant eine Therapie mit Topiramat begonnen. Acht Wochen nach Therapiestart kam die Patientin in stationäre Behandlung. Der Aufenthalt dauerte weniger als drei Wochen; Topiramat wurde von der Patientin gut vertragen. Infolge eines belastenden Lebensereignisses kam es unter kontinuierlicher Therapie mit Topiramat zu einer Destabilisierung des psychischen Zustandsbildes (manische Symptome. Durch eine ambulante Erhöhung der Topiramatdosis bei gleichzeitiger Gabe von Risperidon und Clonazepam konnte jedoch eine neuerliche manische Episode erstmals ambulant behandelt werden. Die Patientin erhält derzeit 200 mg Topiramat pro Tag und ist seit mehr als 20 Monaten nahezu beschwerdefrei.

  6. Nonstoichiometry of Al-Zr intermetallic phases

    Energy Technology Data Exchange (ETDEWEB)

    Radmilovic, V.; Thomas, G.

    1994-06-01

    Nonstoichiometry of metastable cubic {beta}{prime} and equilibrium tetragonal {beta} Al-Zr intermetallic phases of the nominal composition Al{sub 3}Zr in Al-rich alloys has been extensively studied. It is proposed that the ``dark contrast`` of {beta}{prime} core in {beta}{prime}/{sigma}{prime} complex precipitates, in Al-Li-Zr based alloys, is caused by incorporation of Al and Li atoms into the {beta}{prime} phase on Zr sublattice sites, forming nonstoichiometric Al-Zr intermetallic phases, rather than by Li partitioning only. {beta}{prime} particles contain very small amounts of Zr, approximately 5 at.%, much less than the stoichiometric 25 at.% in the Al{sub 3}Zr metastable phase. These particles are, according to simulation of high resolution images, of the Al{sub 3}(Al{sub 0.4}Li{sub 0.4}Zr{sub 0.2}) type. Nonstoichiometric particles of average composition Al{sub 4}Zr and Al{sub 6}Zr are observed also in the binary Al-Zr alloy, even after annealing for several hours at 600{degree}C.

  7. Electroplating Zn-Al Alloy Technology

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The method of controlling separating anode and separating power source was used to perform orthogonal optimization for the parameters in electroplating Zn-Al alloy.The electroplating Zn-Al alloy technology was decided, in which the content of Al is about 12%-15%.

  8. Cenomanian-Turonian biostratigraphy of the Jardas Al Abid area, Al Jabal Al Akhdar, northeast Libya

    Science.gov (United States)

    El Qot, Gamal M.; Abdulsamad, Esam O.

    2016-09-01

    The Upper Cenomanian-Turonian succession exposed at Jardas al'Abid area consists mainly of carbonates with siliciclastic intercalations. This succession is subdivided lithostratigraphically into: Qasr al'Abid (Late Cenomanian) and Al Baniyah (Late Cenomanian-Coniacian) formations. This sequence is relatively rich in macrofossil assemblages especially bivalves, gastropods, and echinoids with rare ammonites. Based on the first occurrence (FO) and last occurrence (LO) of some index species of these macrofossil groups, an integrated biostratigraphic framework has been constructed. The studied Cenomanian-Turonian sequence is subdivided biostratigraphically into three ammonite biozones; Pseudaspidoceras pseudonodosoides Total Range Zone, Choffaticeras segne Total Range Zone, and Coilopoceras requienianum Total Range Zone. Based on the rest of macrofossil assemblages other than the ammonites, eight biozones were recognized; Mecaster batnensis Total Range Zone, Ceratostreon flabellatum-Neithea dutrugei Acme Zone, Costagyra olisiponensis Acme Zone, Pycnodonte (Phygraea) vesicularis vesiculosa Acme Zone, Mytiloides labiatus Total Range Zone = Mecaster turonensis Acme Zone, Rachiosoma rectilineatum-Curvostrea rouvillei-Tylostoma (T.) globosum Assemblage Zone, Radiolites sp.-Apricardia? matheroni Total Range Zone, and Nerinea requieniana Total Range Zone. Most of the proposed biozones are recorded for the first time from Libya. The integration among these biozones as well as local and inter-regional correlation of the biozones have been discussed. The stage boundaries of the studied stratigraphic intervals are discussed, where the Cenomanian/Turonian boundary is delineated at the last occurrence (LO) of Pseudaspidoceras pseudonodosoides (Choffat), while the Turonian/Coniacian boundary is delineated arbitrary being agree with the LO of the Turonian fauna.

  9. Progresses in analyzing 26Al with SMCAMS

    International Nuclear Information System (INIS)

    Shanghai Mini-Cyclotron based Accelerator Mass Spectrometer (SMCAMS) was especially designed for analyzing 14C. In order to accelerate and analyze 26Al the accelerated orbit and beam optics in injection system were calculated and harmonic number and acceleration turns was optimized. Preliminary experiment was carried out. In which a beam current of 1.15 x 10-9A for 27Al- and 0.038 CPS background for 26Al were measured. The limited sensitivity of 26Al/27Al is 5.25 x 10-12. (authors)

  10. Trato verbal paterno al adolescente

    Directory of Open Access Journals (Sweden)

    Rodríguez Juan Carlos

    1995-06-01

    Full Text Available

    En alguna ocasión se ha escuchado una palabra, que causa un sentimiento y a la vez un recuerdo, que lleva a evocar la adolescencia o la infancia, se recuerda quien la pronunciaba y en que ocasión la decía. Este es el poder que tiene una palabra y más aún si es dicha por el padre, puesto que este es la figura significativa que se lleva en la memoria. De aquí nace el interés de realizar un estudio, en donde se describe y analice la percepción y el sentimiento del adolescente, quien en esta etapa es vulnerable al cambio, ya que está buscando su propia identidad; que con el trato verbal paterno la encontrara sin ninguna dificultad o por el contrario nunca la encontrará.

     

  11. Entscheidung als Häresie

    Directory of Open Access Journals (Sweden)

    Jaanus Sooväli

    2014-06-01

    Full Text Available Man könnte sagen, dass Aristoteles so etwas wie eine traditionelle und dominierende Auffassung der Entscheidung in der westlichen Philosophie gründet. Das Ziel dieses Aufsatzes ist es, diese Auffassung von Aristoteles zu entwerfen, einige ihrer wichtigsten Probleme anzusprechen, und sie damit zu kontrastieren, was ich Jacques Derridas häretische „Konzeptualisierung“ der Entscheidung nennen würde. Es wird gezeigt, dass diese häretische Thematisierung von Derrida nicht nur und einfach mit dem traditionellen aristotelischen Begriff bricht, sondern vielmehr auch zu Recht einige seiner wichtigsten Züge auf solcher Weise schärft, dass von diesem radikalisierten Standpunkt die Behandlung von Aristoteles als die Annullierung der Entscheidung zum Vorschein kommt. Es wird zudem impliziert, wie Derridas häretische Auffassung die Erneuerung der Ethik und Politik mit sich bringt.

  12. STUDY OF THE Al/GRAPHITE INTERFACE

    Institute of Scientific and Technical Information of China (English)

    LU HUA(陆华); SHEN DIAN-HONG(沈电洪); DENG XIN-FA(邓新发); XUE QI-KUN(薛其坤); N.FROUMIN; M.POLAK

    2001-01-01

    Thin Al films with a thickness of 20-30nm were prepared by ltra-high vacuum deposition of Al onto a graphite surface arallel to a (0001) basal plane. The samples were annealed up to 1070K. X-ray photoelectron spectroscopy analysis has shown that for temperatures just higher than 770K, a little carbide occurs in the Al film and only an AI-C phase is present at the Al/graphite interface. After nnealing at 970K, the Al4C3 phase can be observed, and the binding energy of the Al2p electrons increases continuously from 72.7 to 74.2eV with increasing temperature up to 1070K. Auger electron spectroscopy depth profiles are measured to investigate the phases existing in the Al film as well as at the Al/graphite interface. It is found that the Al4C3 hase at the interface is the final product of a series of Al carbides from the interfacial reaction between Al and graphite.

  13. AlON粉体的合成

    Institute of Scientific and Technical Information of China (English)

    赵小军; 茹红强; 张宁; 孙有政

    2009-01-01

    以α-Al2O3和AlN为原料,利用高温固相反应在氮气气氛下常压合成了AlON粉体。研究了成分配比、合成温度、保温时间对合成AlON粉体含量的影响,并通过热分析测试了合成过程热流和质量的变化。结果表明,当原料Al2O3和AlN的质量比为81:18、合成工艺为1750℃,2h时,得到AlON相的含量达到95%以上。

  14. Preparation and Characterization of Highly Flexible Al2O3/Al/Al2O3 Hybrid Composite

    Directory of Open Access Journals (Sweden)

    Zhijiang Wang

    2015-01-01

    Full Text Available The natural brittleness of oxide ceramics heavily inhibits their more extensive applications. In present research, a highly flexible Al2O3/Al/Al2O3 hybrid composite was fabricated by employing plasma electrolysis oxidation to in situ grow alumina layers on Al foil, in which an outside layer of nanostructured polycrystalline oxide ceramic was composed of nanosized grains with the size of around 17 nm. Due to shear band formation, nanosized circle bubbles prolonging the crack path, grain rotation, and deformation, the fabricated Al2O3/Al/Al2O3 hybrid composite contains no observable cracks even after being bent on a cylindrical bar with a curvature of 1.5 mm. The composite exhibits alumina stiffness at the elastic stage and aluminum ductility during plastic deformation, which provides high flexibility with the well-integrated properties of the components. In a synergistic interaction, the alumina on the outside exhibited a strain of 0.33% at room temperature, which was higher than optimum value of 0.25% presented by reported most flexible oxide ceramics. With the unique characteristics and properties, the Al2O3/Al/Al2O3 composite demonstrates a great potential for various engineering applications.

  15. MARTENSITIC TRANSFORMATION AND THERMAL STABILITY IN Cu-Al-Co AND Cu-Al-Zr ALLOYS

    Institute of Scientific and Technical Information of China (English)

    Y. Q. Ma; C.B. Jiang; H.B. Xu

    2003-01-01

    Cu-Al-Co and Cu-Al-Zr alloys were explored with Co or Zr additions in Cu-Al alloys for high temperature shape memory alloys. Samples were quenched after homogenized at 850℃ for 48h. It was found that both Cu-Al-Co and Cu-Al-Zr show AlCu3 martensitic phase at room temperature and exhibit martensitic transformation temperatures higher than 200℃, showing the potentials for developing as high temperature shape memory alloys. Thermal cycles were performed by DSC instrument on both Cu-Al-Co and Cu-Al-Zr alloys. The results show that Cu-Al-Co loses its martensitic transformation after five thermal cycles, and Cu-Al-Zr exhibits no martensitic transformation in the second thermal cycle.

  16. Friction Stir Welding of Al 5052 with Al 6061 Alloys

    Directory of Open Access Journals (Sweden)

    N. T. Kumbhar

    2012-01-01

    Full Text Available Friction stir welding (FSW, a solid-state joining technique, is being extensively used in similar as well as dissimilar joining of Al, Mg, Cu, Ti, and their alloys. In the present study, friction stir welding of two aluminium alloys—AA6061 and AA5052—was carried out at various combinations of tool rotation speeds and tool traverse speeds. The transverse cross-section of the weld was used for optical as well as electron microscopy observations. The microstructural studies were used to get an indication of the extent of material mixing both at the macro- and microscales. It was observed that, at the interface region, both materials exhibited similar texture despite the nonrigorous mixing of the materials in the nugget. The extent of interdiffusion of alloying elements at the interface was studied using electron probe microanalysis. The tensile testing evaluation of these specimens showed good mechanical properties. The interdiffusion of alloying elements and development of similar orientations in the nugget could have contributed to the better tensile properties of the friction-stir-welded AA5052-AA6061 specimens.

  17. Efficiency droop in high-Al-content AlGaN/AlGaN quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Tamulaitis, G.; Mickevicius, J.; Kazlauskas, K.; Zukauskas, A. [Institute of Applied Research and Department of Semiconductor Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius (Lithuania); Shur, M.S. [Department of ECE and CIE, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180 (United States); Yang, J.; Gaska, R. [Sensor Electronic Technology Inc., 1195 Atlas Road, Columbia, SC 29209 (United States)

    2011-07-15

    Excitation power density dependence of photoluminescence (PL) efficiency is studied in the temperature range from 8 to 300 K for AlGaN multiple quantum well structures containing quantum wells of different width. PL efficiency droop is observed and dependence of the droop effect on the well width and lattice temperature is discussed. Photoluminescence band shape reveals strong carrier heating. It is shown that the heating effect has a substantial influence on the photoluminescence efficiency droop, especially at low lattice temperatures. Fitting of the temperature dependence of the PL band width with that obtained by the Monte Carlo simulation of carrier (exciton) hopping via localized states shows that (i) the potential fluctuations can be fairly accurately described using a double-scaled potential profile model, (ii) the localization becomes stronger in narrower quantum wells. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  18. Atomic structure and oxygen deficiency of the ultrathin aluminium oxide barrier in Al/AlOx/Al Josephson junctions

    OpenAIRE

    Lunjie Zeng; Dung Trung Tran; Cheuk-Wai Tai; Gunnar Svensson; Eva Olsson

    2016-01-01

    Al/AlOx/Al Josephson junctions are the building blocks of a wide range of superconducting quantum devices that are key elements for quantum computers, extremely sensitive magnetometers and radiation detectors. The properties of the junctions and the superconducting quantum devices are determined by the atomic structure of the tunnel barrier. The nanoscale dimension and disordered nature of the barrier oxide have been challenges for the direct experimental investigation of the atomic structure...

  19. Al-Si/Al2O3 in situ composite prepared by displacement reaction of CuO/Al system

    Directory of Open Access Journals (Sweden)

    Zhang Jing

    2010-02-01

    Full Text Available Al2O3 particle-reinforced ZL109 composite was prepared by in situ reaction between CuO and Al. The microstructure was observed by means of OM, SEM and TEM. The Al2O3 particles in sub-micron sizes distribute uniformly in the matrix, and the Cu displaced from the in situ reaction forms net-like alloy phases with other alloy elements. The hardness and the tensile strength of the composites at room temperature have a slight increase as compared to that of the matrix. However, the tensile strength at 350 ℃ has reached 90.23 MPa, or 16.92 MPa higher than that of the matrix. The mechanism of the reaction in the CuO/Al system was studied by using of differential scanning calorimetry(DSC and thermodynamic calculation. The reaction between CuO and Al involves two steps. First, CuO reacts with Al to form Cu2O and Al2O3 at the melting temperature of the matrix alloy, and second, Cu2O reacts with Al to form Cu and Al2O3 at a higher temperature. At ZL109 casting temperature of 750–780 ℃, the second step can also take place because of the effect of exothermic reaction of the first step.

  20. Entrevista al narrador Tommaso Pincio

    Directory of Open Access Journals (Sweden)

    Franco Zangrilli

    2016-07-01

    Full Text Available El autor Tommaso Pincio, seudónimo di Marco Colapietro (Roma, 1963, es sin lugar a dudas uno de los narradores de mayor proyección en el panorama literario de los últimos tiempos. Iniciada su carrera en 1999 con M., ha publicado títulos como Lo spazio sfinito (2000 y Un amore dell'altro mondo (2002, en el que narra la vida de Kurt Cobain, líder del grupo Nirvana, a través de la visión de un amigo imaginario. A estas dos novelas siguieron La ragazza che non era lei (2005, Gli alieni (2006 o Cinacittà. Memorie del mio delitto efferato (2008, ambientada en una Roma colonizada por los chinos y abandonada por los mismos romanos a causa de problemas medioambientales. Títulos como L'hotel a zero stelle (2011, un ensayo autobiográfico en el que plantea diálogos ficticios con algunos de los grandes nombres de la literatura o la más reciente Panorama (2015, le han hecho valerse un hueco provilegiado entre los nuevos narradores surgidos en estas primeras décadas de siglo. Justamente la publicación de esta última novela, Panorama, ha servido de excusa al profesor Franco Zangrilli, gran conocedor de su obra, a plantearle algunas preguntas sobre temas clave de su producción.

  1. Fabrication of TiAl3 coating on TiAl-based alloy by Al electrodeposition from dimethylsulfone bath and subsequent annealing

    OpenAIRE

    Miyake, Masao; Tajikara, Seiya; Hirato, Tetsuji

    2011-01-01

    TiAl3 coating was formed on TiAl alloy by Al electrodeposition from a dimethylsulfone (DMSO2) bath and subsequent annealing. Before the Al electrodeposition, anodic dissolution of TiAl substrate in the DMSO2 bath was conducted to remove the surface oxide layer of the TiAl substrate. By performing the Al electrodeposition immediately after the anodic dissolution, uniform Al films adherent to the TiAl substrate could be obtained. Annealing at 650–1000 °C yielded a single TiAl3 layer or two laye...

  2. Seroprevalencia de babesiosis bovina en la hacienda Vegas de la Clara, Gómez Plata (Antioquia, 2008

    Directory of Open Access Journals (Sweden)

    Richard Zapata Salas

    2011-06-01

    Full Text Available La babesiosis es una enfermedad del ganado bovino transmitida por la garrapata Rhipicephalus (Boophilus microplus y causada por los parásitos protozoarios Babesia bovis y B. bigemina. Una zona se considera epizootiológicamente estable frente a Babesia spp, cuando el 75% de los bovinos entre las edades de 3 a 9 meses son serorreactivos (IgG frente a Babesia bovis y Babesia bigemina y no hay evidencia de signos clínicos. El objetivo de esta investigación fue determinar la seroprevalencia de Babesia bovis y Babesia bigemina en el ganado bovino de la hacienda Vegas de la Clara (Universidad de Antioquia, Gómez Plata, Antioquia, por medio de inmunofluorescencia indirecta. Se diseñó un estudio descriptivo prospectivo con análisis de corte transversal. Fue evaluada toda la población bovina de la hacienda Vegas de la Clara (n = 118. Las muestras fueron evaluadas por inmunofluorescencia indirecta para la detección de anticuerpos tipo IgG específicos contra Babesia bovis y B. bigemina. La serorreactividad obtenida en los bovinos evaluados, para al menos una especie de Babesia fue del 89,8%, para Babesia bovis del 83,8%, mientras que para B. bigemina del 61%. Se obtuvo una relación estadísticamente significativa entre la serorreactividad para B. bigemina y la frecuencia del tratamiento garrapaticida. La serorreactividad indica estabilidad enzoótica en el hato para B. bovis, mientras que para B. bigemina se encontró que la frecuencia del tratamiento garrapaticida interrumpe su ciclo de transmisión.

  3. Fabrication of AlN-TiC/Al composites by gas injection processing

    Institute of Scientific and Technical Information of China (English)

    YU Huashun; CHEN Hongmei; MA Rendian; MIN Guanghui

    2006-01-01

    The fabrication of AlN-TiC/Al composites by carbon-and nitrogen-containing gas injection into Al-Mg-Ti melts was studied. It was shown that AlN and TiC particles could be formed by the in situ reaction of mixture gas (N2+C2H2+NH3) with Al-Mg-Ti melts. The condition for the formation of AlN was that the treatment temperature must be higher than 1373 K, and the amounts of AlN and TiC increased with the increase of the treatment temperature and the gas injection time.It was considered that AlN was formed by the direct reaction of Al with nitrogen-containing gas at the interface of the gas bubble and the melt. However, the mechanism of TiC formation is a combination mechanism of solution-precipitation and solid-liquid reaction.

  4. Orientation relationship of eutectoid FeAl and FeAl2

    Science.gov (United States)

    Scherf, A.; Kauffmann, A.; Kauffmann-Weiss, S.; Scherer, T.; Li, X.; Stein, F.; Heilmaier, M.

    2016-01-01

    Fe–Al alloys in the aluminium range of 55–65 at.% exhibit a lamellar microstructure of B2-ordered FeAl and triclinic FeAl2, which is caused by a eutectoid decomposition of the high-temperature Fe5Al8 phase, the so-called ∊ phase. The orientation relationship of FeAl and FeAl2 has previously been studied by Bastin et al. [J. Cryst. Growth (1978 ▸), 43, 745] and Hirata et al. [Philos. Mag. Lett. (2008 ▸), 88, 491]. Since both results are based on different crystallographic data regarding FeAl2, the data are re-evaluated with respect to a recent re-determination of the FeAl2 phase provided by Chumak et al. [Acta Cryst. (2010 ▸), C66, i87]. It is found that both orientation relationships match subsequent to a rotation operation of 180° about a 〈112〉 crystallographic axis of FeAl or by applying the inversion symmetry of the FeAl2 crystal structure as suggested by the Chumak data set. Experimental evidence for the validity of the previously determined orientation relationships was found in as-cast fully lamellar material (random texture) as well as directionally solidified material (∼〈110〉FeAl || solidification direction) by means of orientation imaging microscopy and global texture measurements. In addition, a preferential interface between FeAl and FeAl2 was identified by means of trace analyses using cross sectioning with a focused ion beam. On the basis of these habit planes the orientation relationship between the two phases can be described by (01)FeAl || (114) and [111]FeAl || [10]. There is no evidence for twinning within FeAl lamellae or alternating orientations of FeAl lamellae. Based on the determined orientation and interface data, an atomistic model of the structure relationship of Fe5Al8, FeAl and FeAl2 in the vicinity of the eutectoid decomposition is derived. This model is analysed with respect to the strain which has to be accommodated at the interface of FeAl and FeAl2. PMID:27047304

  5. Electron channelling enhanced microanalysis on Ni-Al-Mn and Al-Mn-Si

    International Nuclear Information System (INIS)

    Atom location by channelling enhanced microanalysis (ALCHEMI) was performed for Ni-Al-Mn compounds and Al-Mn-Si quasicrystals. For Ni75Al25-xMnx (x=5,9) with the L12-type structure, an occupation fraction of Mn atoms at the Ni site was quantitatively determined using planar channelling conditions. The occupation fraction increases with the Mn concentration or by quenching the compound from high temperature. In quasicrystals of Al74Mn20Si6 and Al68Mn20Ru8Si4, axial channelling conditions were used to locate Si and Ru, respectively. It was shown that Si atoms occupy the Al site in Al74Mn20Si6 whereas Ru atoms occupy the site different from that of Al in Al68Mn20Ru8Si4. (author)

  6. A New Phase in ALS Research.

    Science.gov (United States)

    Chong, P Andrew; Forman-Kay, Julie D

    2016-09-01

    In this issue of Structure, Conicella et al. (2016) present evidence that the low complexity C-terminal region of TDP-43 undergoes liquid-liquid phase separation. ALS-associated mutations alter this phase separation process, providing a possible mechanism for the pathology caused by these TDP-43 mutations. The work is strongly supportive of toxic loss of RNA processing function in ALS. PMID:27602988

  7. The wobbler mouse, an ALS animal model

    OpenAIRE

    Moser, Jakob Maximilian; Bigini, Paolo; Schmitt-John, Thomas

    2013-01-01

    This review article is focused on the research progress made utilizing the wobbler mouse as animal model for human motor neuron diseases, especially the amyotrophic lateral sclerosis (ALS). The wobbler mouse develops progressive degeneration of upper and lower motor neurons and shows striking similarities to ALS. The cellular effects of the wobbler mutation, cellular transport defects, neurofilament aggregation, neuronal hyperexcitability and neuroinflammation closely resemble human ALS. Now,...

  8. Casting fabrication of in situ Al3Ti-Al composites and their wear behaviors

    Institute of Scientific and Technical Information of China (English)

    Chen Tijun; Li Jian; Hao Yuan

    2009-01-01

    The Al3li intermetallic reinforced pure Al, Al-13Si and Al-17Cu matrix composites were prepared by casting method. Their microstructures and dry sliding wear behaviors at room temperature and 100℃ were particularly investigated. The results indicated that the Al3Ti phases in these composites were all in flaky form. But the aspect ratio of the Al3Ti platelets decreased with the increase of Ti content in the pure AI, Al-Cu and Al-Si matrix composites, in order of effectiveness. The effect of Si on the Al3Ti morphology seemed to be greater than that of Cu. The distributions of the Al3Ti platelets were different in the different matrix composites, leading to different grain refining effects. Except for the sub-wear regime of adhesive wear, the plastic deformation induced wear was a dominant wear mechanism for all of the composites at room temperature and 100℃. Increasing the testing temperature, decreasing the Al3Ti content or the hardness of materials could enhance these two wear mechanisms, and thus increase the wear rate. The Al-Cu matrix composite had the best wear resistance, while the pure Al matrix composite showed the worst for the same Ti content. These differences or changes were attributed to the differences in materials' hardness or the strengthening effects of the Al3Ti platelets.

  9. Groente- en fruitafvallen als veevoer : inventarisatie

    NARCIS (Netherlands)

    Vries, de A.

    1982-01-01

    Een onderzoek wat betreft hoeveelheden, bewaring, samenstelling, verteerbaarheid en eventueel aanwezige ongewenste stoffen van de bij- en afvalprodukten van groenten en fruit als veevoer voor herkauwers

  10. Genetics of Familial and Sporadic ALS

    Science.gov (United States)

    2016-03-21

    Amyotrophic Lateral Sclerosis (ALS); Familial Amyotrophic Lateral Sclerosis; Amyotrophic Lateral Sclerosis With Frontotemporal Dementia; Lou Gehrig's Disease; Motor Neuron Disease; Primary Lateral Sclerosis

  11. Growth of CdTe: Al films

    International Nuclear Information System (INIS)

    CdTe: AI films were grown by the close space vapor transport technique combined with free evaporation (CSVT-FE). The Aluminum (Al) evaporation was made by two kinds of sources: one made of graphite and the other of tantalum. The films were deposited on glass substrates. The Al source temperature was varied maintaining the CdTe source temperature fixed as well as the substrate temperature. The films were characterized by x-ray energy dispersive analysis (EDAX), x-ray diffraction and optical transmission. The results showed for the films grown with the graphite source for Al evaporation, the Al did not incorporate in the CdTe matrix, at least to the level of EDAX sensitivity; they maintained the same crystal structure and band gap. For the samples grown with the tantalum source, we were able to incorporate the Al. The x-ray diffraction patterns show that the films have a crystal structure that depends on Al concentration. They were cubic up to 2.16 at. % Al concentration; for 19.65 at. % we found a mixed phase; for Al concentration higher than 21 at. % the films were amorphous. For samples with cubic structure it was found that the lattice parameter decreases and the band gap increases with Al concentration. (Author)

  12. Influence of Al Composition on the Microstructure of B Alloyed Ni3Al Synthesized under Compression

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It was shown by TEM and X-ray analysis that Ni3Al is the mainphase of the intermetallic synthesized under compression from the powder mixture of Ni with Al alloyed by B. The Ni3B is a secondary phase. The value of the lattice parameter of the intermetallic Ni3Al with and without B increases when the concentration of Al increases. The increase in Al concentration from 23.5 to 25.0 in the initial powder mixture leads to decreasing the solubility of B in the Ni3Al phase.

  13. 关于w-al-CL空间%On w-al-CL Spaces

    Institute of Scientific and Technical Information of China (English)

    林丽琼; 张云南

    2011-01-01

    给出w-al-CL空间的定义,比较几种CL性的关系,讨论w-al-CL空间的c0和与l1和的稳定性,并讨论C(K,X)空间的w-al-CL性.%Gives the definition of w-al-CL spaces, compare the relationship of some properties of CL, discusses the stability of c0 -sums and l1 -sums of w-al-CL spaces, and discusses the property of w-al-CL of C(K,X) spaces.

  14. Response to Signorovitch et al.

    Science.gov (United States)

    Flot, Jean-François; Debortoli, Nicolas; Hallet, Bernard; Van Doninck, Karine

    2016-08-22

    Signorovitch et al.[1] comment that an Oenothera-like meiosis [2] could produce a pattern similar to what we observed in our study of natural isolates of the bdelloid rotifer Adineta vaga, which we attributed to horizontal gene transfers (HGTs) [3]. Indeed, our HGT hypothesis appears at first sight difficult to conciliate with their observation of a congruent pattern of allele sharing at four large loci possibly located on different chromosomes [4]. However, one might imagine conditions under which massive horizontal gene transfer between bdelloid individuals could produce such a pattern, notably if the individuals involved had previously lost most of their heterozygosity because of their exposure to frequent desiccation (which produces DNA double-strand breaks [5]). In the published A. vaga genome the loss of heterozygosity due to large-scale gene conversion events or break-induced replication covers only about 10% of the genome [6], but this percentage may be much higher in environmental isolates that often experience dessication. Besides, if an Oenothera-like mode of meiosis occurs in bdelloids frequently enough to be detected in a single sampling of 29 individuals (as in [4]), one would expect males and meiosis to be observed at least occasionally, and instances of congruent allele sharing across loci should turn up frequently in genetic surveys. This was not the case in [3]: among the 82 A. vaga individuals sequenced for four nuclear markers, no trio of individuals presented congruent patterns of shared sequences at different loci. For these reasons, and in the absence of any direct evidence for an Oenothera-like meiosis in bdelloids, we still consider inter-bdelloid HGTs a more parsimonious explanation for our results. PMID:27554651

  15. Atomic structure and oxygen deficiency of the ultrathin aluminium oxide barrier in Al/AlOx/Al Josephson junctions.

    Science.gov (United States)

    Zeng, Lunjie; Tran, Dung Trung; Tai, Cheuk-Wai; Svensson, Gunnar; Olsson, Eva

    2016-01-01

    Al/AlOx/Al Josephson junctions are the building blocks of a wide range of superconducting quantum devices that are key elements for quantum computers, extremely sensitive magnetometers and radiation detectors. The properties of the junctions and the superconducting quantum devices are determined by the atomic structure of the tunnel barrier. The nanoscale dimension and disordered nature of the barrier oxide have been challenges for the direct experimental investigation of the atomic structure of the tunnel barrier. Here we show that the miniaturized dimension of the barrier and the interfacial interaction between crystalline Al and amorphous AlOx give rise to oxygen deficiency at the metal/oxide interfaces. In the interior of the barrier, the oxide resembles the atomic structure of bulk aluminium oxide. Atomic defects such as oxygen vacancies at the interfaces can be the origin of the two-level systems and contribute to decoherence and noise in superconducting quantum circuits. PMID:27403611

  16. Atomic structure and oxygen deficiency of the ultrathin aluminium oxide barrier in Al/AlOx/Al Josephson junctions

    Science.gov (United States)

    Zeng, Lunjie; Tran, Dung Trung; Tai, Cheuk-Wai; Svensson, Gunnar; Olsson, Eva

    2016-07-01

    Al/AlOx/Al Josephson junctions are the building blocks of a wide range of superconducting quantum devices that are key elements for quantum computers, extremely sensitive magnetometers and radiation detectors. The properties of the junctions and the superconducting quantum devices are determined by the atomic structure of the tunnel barrier. The nanoscale dimension and disordered nature of the barrier oxide have been challenges for the direct experimental investigation of the atomic structure of the tunnel barrier. Here we show that the miniaturized dimension of the barrier and the interfacial interaction between crystalline Al and amorphous AlOx give rise to oxygen deficiency at the metal/oxide interfaces. In the interior of the barrier, the oxide resembles the atomic structure of bulk aluminium oxide. Atomic defects such as oxygen vacancies at the interfaces can be the origin of the two-level systems and contribute to decoherence and noise in superconducting quantum circuits.

  17. Kritik al-Ghazali terhadap Kekekalan Alam

    Directory of Open Access Journals (Sweden)

    Sahidi Mustafa

    2015-12-01

    Full Text Available The concept of the creation of universe offered by Neo-Platonism philosopher such as al-Kindi, al-Farabi, and Ibnu Sina are philosophical concept existed and came as an early moment of development of Islamic philosophy interrelated to God, ultimately about his Existence and Characteristics. One of the topics is how God created the universe. According to al-Farabi and Ibnu Sina, God created this universe by way of emanation in order to prevent Himself from the new attitudes. Consequently, universe has eternal feature (qadim as God as well, in the case of everything overflowed from qadim is also qadim. Al-Ghazali refuted this theory because it contradicted with al Qur’an’s thought which clearly explained that God created the entire universe. The universe should not qadim and it means that God existed in the first, and then created universe later as we know today. On the contrary, in the view of Muslim philosopher, the universe should be qadim because God created it from all eternity. For them, it is impossible that God existed by Himself without any creation before. God, according to them is impossible to be changed, so that is impossible as well if God changed from did not create yet before and then creates. Al-Ghazali persistently opposed the concept of eternity. Al Ghazali saw if this universe is qadim so it is impossible that universe created by God. The concept of qadim will led to the conclusion that universe born by itself, it was not created by God. This critique has been written by al-Ghazali in Tahafut al-Falasifah. This paper will present the concept of eternity which was discussed by al-Farabi and Ibn Sina and al Ghazali’s critique toward it as well.

  18. Untersuchung der Nitridierung V/Al-intermetallischer Phasen

    OpenAIRE

    Lewalter, Hartmut Berthold

    2004-01-01

    Schichten V/Al-Intermetallischer Phasen und Schichten aus V(Al) (Schichtdicken 150- 300 nm) wurden durch Interdiffusion von V/Al- und V5Al8/V-Mehrfachschichten bei 400-800°C im Vakuum bei 3 x 10-8 mbar hergestellt. Des Weiteren wurden V5Al8-Schichten durch Sputtern einer V5Al8-Legierung erzeugt. Die Gesamtstöchiometrie der Schichten lag zwischen Al0,86V0,14 und Al0,19V0,81. Als Substrat dienten einkristalline (012) Saphirwafer. Die V/Al-Intermetallischen Phasen und V(Al) wurden im RTP-System ...

  19. Influence of AlN thickness on AlGaN epilayer grown by MOCVD

    Science.gov (United States)

    Jayasakthi, M.; Juillaguet, S.; Peyre, H.; Konczewicz, L.; Baskar, K.; Contreras, S.

    2016-10-01

    AlGaN/AlN layers were grown by metalorganic chemical vapor deposition (MOCVD) on sapphire substrates. The AlN buffer thickness was varied from 400 nm to 800 nm. The AlGaN layer thickness was 1000 nm. The crystalline quality, thickness and composition of AlGaN were determined using high resolution X-ray diffraction (HRXRD). The threading dislocation density (TDD) was found to decrease with increase of AlN layer thickness. Reciprocal space mapping (RSM) was used to estimate the strain and relaxation between AlGaN and AlN. The optical properties of AlGaN layers were investigated by temperature dependent photoluminescence (PL). PL intensities of AlGaN layers increases with increasing the AlN thickness. The surface morphology of AlGaN was studied by atomic force microscopy (AFM). Root mean square (RMS) roughness values were found to be decreased while increase of AlN thickness.

  20. Babesia bovis and B. bigemina DNA detected in cattle and ticks from Zimbabwe by polymerase chain reaction

    Directory of Open Access Journals (Sweden)

    I. Smeenk

    2000-07-01

    Full Text Available From blood collected from 94 cattle at 12 locations in the eastern and northeastern areas of Zimbabwe, DNA was extracted and analysed by polymerase chain reaction with primers previously reported to be specific for Babesia bigemina and Babesia bovis. Overall, DNA of Babesia bigemina was detected in the blood of 33/94 (35 % cattle and DNA from B. bovis was detected in 27/58 (47 % of cattle. The prevalence of DNA of B. bigemina was significantly higher in young animals (<2 years (23/46 than in animals over 2 years of age (10/48; (chi2 = 8.77; P < 0.01 %. Although tick sampling was not thorough, Boophilus decoloratus could be collected at 7/9 sites sampled and Boophilus microplus at 4/9 sites. Of the 20 B. decoloratus allowed to oviposit before PCR analysis, 1 (5 % contained DNA that could be amplified with primers for B. bigemina while 12 (60 % were positive with primers for B. bovis. Of the B. microplus allowed to oviposit, 11/16 (69 % were positive for B. bovis DNAby PCR and 2/16 (12 % were positive for B. bigemina.

  1. Canis familiaris, UN NUEVO HOSPEDERO DE Ornithodoros (A. puertoricensis FOX, 1947 (ACARI: IXODIDA EN COLOMBIA Canis familiaris, a New Host of Ornithodoros (A. puertoricensis Fox, 1947 (Acari: Ixodida in Colombia

    Directory of Open Access Journals (Sweden)

    LUIS E PATERNINA

    Full Text Available Las garrapatas revisten gran importancia en el campo biomédico por sus hábitos hematófagos y asociación con la transmisión de agentes patógenos a humanos y animales. El objetivo de esta investigación fue establecer las especies de garrapatas que parasitan perros en tres poblaciones del área rural del Caribe colombiano. Durante los meses de agosto y diciembre del año 2006 se realizó búsqueda activa de garrapatas sobre caninos domésticos de las localidades de El Campín, Sabanas del Potrero y Escobar Arriba, departamento de Sucre. Las garrapatas recolectadas fueron almacenadas en viales con etanol al 70% e identificadas empleando claves morfológicas de referencia para cada familia. Para la determinación de especie en la familia Argasidae se realizaron estimaciones morfométricas de estructuras externas. Se recolectaron 420 garrapatas a partir de 50 caninos infestados, de un total de 134 perros examinados, que corresponde a una tasa de infestación del 37,3%. Las garrapatas fueron identificadas como Rhipicephalus sanguineus, Rhipicephalus (Boophilus microplus y Amblyomma ovale pertenecientes a la familia Ixodidae, y Ornithodoros (Alectorobius puertoricensis de la familia Argasidae. La especie predominante fue R. sanguineus (92,1% en los estados de larva, ninfa y adulto, seguida por larvas de O. puertoricensis, que fueron halladas en menor número sobre caninos de las tres localidades. Se registra, por primera vez en América, el parasitismo de O. puertoricensis sobre caninos domésticos y se confirma su presencia en Colombia.Ticks are very important from the biomedical point of view, by their hematophagic activity and their role in the transmission of pathogenic microorganisms to man and animals. The main goal of this work was to establish the tick species parasiting dogs in three rural localities of the Colombian Caribbean. From August to December 2006, an active search of ticks on dogs was carried out in the localities of El Camp

  2. The theory of the moon in the al-Zij al-Kamil fi-l-taalim of Ibn al-Ha'im

    OpenAIRE

    Puig i Tàrrech, Roser

    2000-01-01

    Al the beginning of Ihe thirteenth cenrury (60tH I 1204-1205) Abli Muhammad Abd al-Haqq al-Ghafiqi al-lshbiIi known as Ibn al-Ha'im composed his work entitled al-Zi] al-Kamil fi-l-Taalim in honour of the Caliph Abu Abd Allah Muhammad al-Nasir (who reigned from 1199- 1213). All we know of lbn al-Ha'im's live is that he came from Seville and that he appears to have worked in North Africa.

  3. Geluk als onderwerp van wetenschappelijk onderzoek

    NARCIS (Netherlands)

    R. Veenhoven (Ruut)

    1970-01-01

    textabstractAbstract in Dutch: Geluk wordt gedefinieerd als overwegende tevredenheid met het leven als geheel. Dit artikel geeft een overzicht van het onderzoek naar dat verschijnsel. Geluk blijkt deels afhankelijk van persoonlijke eigenschappen. Zo blijkt ondermeer dat gelukkige mensen over het alg

  4. 75 FR 62858 - United States, et al.

    Science.gov (United States)

    2010-10-13

    ... Antitrust Division United States, et al. v. American Express Company, et al.; Proposed Final Judgment and... been filed with the United States District Court for the Eastern District of New York in United States..., 2010, the United States and seven States filed a Complaint alleging that certain rules, policies,...

  5. Als je vrienden hebt dan win je

    NARCIS (Netherlands)

    Effing, R. (Robin); Huibers, T. (Theo); Krosse, de L. (Luc)

    2010-01-01

    Als je wint, heb je vrienden’ is een Nederlandse klassieker van Herman Brood en Henny Vrienten. Hiermee werd de gevoelige snaar bloot gelegd dat pas als je hebt gewonnen je vrienden hebt. Rijen dik, echte vrienden. In de politiek werkt het andersom; je moet vrienden (stemmen) hebben, ve

  6. Diana Al-Hadid: Identity and Heritage

    Science.gov (United States)

    Jungerberg, Tom; Smith, Anna; Borsh, Colleen

    2012-01-01

    Diana Al-Hadid's sculptures reflect the many locations, cultures, histories, and mythologies that have shaped her as an artist. In large-scale works which have the appearance of architectural ruins, Al-Hadid employs imagery drawn from many diverse interests including science and technology, history, and literature. She also incorporates images and…

  7. Kus on al-Zarqawi? / Aadu Hiietamm

    Index Scriptorium Estoniae

    Hiietamm, Aadu, 1954-

    2005-01-01

    Suurbritannia nädalalehe Sunday Times andmetel on Iraagi tagaotsituim mässaja, terrorivõrgustiku al Qaeda liitlane Abu-Musab al-Zarqawi pärast USA raketirünnakus haavatasaamist riigist põgenenud

  8. Al-Farabi dan Filsafat Kenabian

    Directory of Open Access Journals (Sweden)

    Qosim Nursheha Dzulhadi

    2014-03-01

    Full Text Available Artikel ini mengulas pemikiran al-Farabi tentang konsep kenabian dalam Islam. Masalah berawal dari adanya pemikiran yang menolak konsep kenabian pada umumnya dan kenabian Nabi Muhammad SAW khususnya. Sebagaimana yang dilontarkan oleh Muhammad Ahmad ibn al-Ruwandi. Ia mengatakan bahwa nabi sebenarnya tidak diperlukan manusia karena Tuhan telah mengaruniakan akal kepada manusia tanpa terkecuali. Dengan akal ini, manusia dapat mengetahui Tuhan beserta segala nikmat Nya dan dapat pula mengetahui perbuatan baik dan buruk, menerima suruhan dan larangan-Nya. Dengan demikian, nabi dengan segala fungsinya tidak diperlukan lagi. Bahkan, kitab suci pun tidak berguna untuk dibaca. Lebih berguna membaca buku filsafat Epicurus, Plato, Aristoteles, dan buku astronomi, logika, serta obat-obatan. Hal ini tentunya bertolak belakang dengan yang diajarkan dalam Islam. Beriman kepada nabi nabi merupakan hal inti dalam ajaran agama ini. Atas dasar itu al-Farabi bereaksi keras. Baginya, pandangan Ibn al-Ruwandi di atas tidak dapat dibenarkan, khususnya dari sisi akidah Islam. Sebagai al-Mu‘allim al-Tsani (Guru Kedua, karena prestasinya dalam menjelaskan dan mengulas-ulang filsafat Aristoteles, al-Farabi mengkritik secara sistematik pandangan menyimpang al-Ruwandi di atas.

  9. The role of inclusions in ALS pathogenesis

    NARCIS (Netherlands)

    V. van Dis (Vera)

    2012-01-01

    textabstractAmyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease that primarily afflicts motor neurons, leading to paralysis and death within 3 to 5 years after diagnosis. Genetic studies have uncovered multiple genetic defects causing familial forms of ALS and mutations oc

  10. Data supporting Al-Abed et al., Environ. Sci.: Nano, 2016,

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data files representing each of the Figures and Tables published in Al-Abed et al., Environ. Sci.: Nano, 2016, 3, 593. The data file names identify the Figure or...

  11. Effect of Al coating conditions on laser weldability of Al coated steel sheet

    Institute of Scientific and Technical Information of China (English)

    Jung-Han LEE; Jong-Do KIM; Jin-Seok OH; Seo-Jeong PARK

    2009-01-01

    Al coated steel sheets with excellent heat resistance, thermal reflection, and corrosion resistance are widely used in various applications. The laser weldability of the Al coated steel sheet for full penetration welding was reported. The phenomenon caused by intermixed aluminum and behavior of aluminum in the weld were investigated. Al coated steel sheets that have various thickness and coating mass were prepared for laser welding. The effects of parameters such as welding conditions and Al coating conditions were investigated. Al content mixed in the weld after laser welding was evaluated, and then a correlation between the mixed Al and mechanical properties was investigated. The results show that the Al-rich zones which have Fe-Al intermetallic compounds are found in the weld. The intermetallic compounds cause the decreased strength of the weld.

  12. Kinetic Monte Carlo of transport processes in Al/AlOx/Au-layers: Impact of defects

    Directory of Open Access Journals (Sweden)

    Benedikt Weiler

    2016-09-01

    Full Text Available Ultrathin films of alumina were investigated by a compact kMC-model. Experimental jV-curves from Al/AlOx/Au-junctions with plasma- and thermal-grown AlOx were fitted by simulated ones. We found dominant defects at 2.3-2.5 eV below CBM for AlOx with an effective mass mox∗=0.35 m0 and a barrier EB,Al/AlOx≈2.8 eV in agreement with literature. The parameterization is extended to varying defect levels, defect densities, injection barriers, effective masses and the thickness of AlOx. Thus, dominant charge transport processes and implications on the relevance of defects are derived and AlOx parameters are specified which are detrimental for the operation of devices.

  13. Konsepsi Ibnu Jarir Al-Tabari Tentang Al-Qur’an, Tafsir Dan Ta’wil

    Directory of Open Access Journals (Sweden)

    A.M Ismatulloh

    2012-12-01

    Full Text Available The objective of this research is to describe the concept of Ibnu Jarir al-Tabari about al-Qur’an, tafsir and ta’wil. Ibn Jarir al-Tabari is an outstanding expert in the classic Islamic tradition. His knowledge in hadits, fiqh, lughah, history, and tafseer is unquestionable. This study uses an analytical descriptive design. The findings show that: Firstly, in defining al-Qur’an, al-Tabari focused on the al-Qur’an as an Arabic language text, not in other language. Secondly, al-Qur’an is written in sab’ah ahruf. It means that there are 7 different kinds of language with the same meaning. Thirdly, al-Qur’an comes from seven heaven’s door. Fourthly, there is no different word between tafseer and ta’wil. They have same meaning. These concepts are different to other concepts proposed by other ulama.

  14. Thermoluminescence properties of AlN ceramics

    DEFF Research Database (Denmark)

    Trinkler, L.; Christensen, P.; Agersnap Larsen, N.;

    1998-01-01

    The paper describes thermoluminescence (TL) properties of AlN:Y2O3 ceramics irradiated with ionising radiation. A high TL sensitivity of AlN:Y2O3 ceramics to radiation encouraged a study of the AlN ceramics for application as a dosimetric material. The paper presents experimental data on: glow...... curve, emission spectrum, dose response, energy dependence, influence of heating rate and fading rate. The measured TL characteristics were compared with those of well-known, widely used TLDs, i.e. LiF:Mg,Ti, LiF:Mg,Cu,P and Al2O3:C. It is concluded that AlN:Y2O3 ceramics showing a radiation sensitivity...

  15. High temperature creep behaviour of Al-rich Ti-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, D; Heilmaier, M; Saage, H [Otto von Guericke University Magdeburg, Institute for Materials and Joining Technology, PO Box 4120, D-39016 Magdeburg (Germany); Aguilar, J; Schmitz, G J; Drevermann, A [ACCESS e.V., Intzestrasse 5, D-52072 Aachen (Germany); Palm, M; Stein, F; Engberding, N [Max-Planck-Institut fuer Eisenforschung GmbH, Max-Planck-Str. 1, D-40237 Duesseldorf (Germany); Kelm, K; Irsen, S, E-mail: daniel.sturm@ovgu.d [Stiftung caesar, Electron Microscopy, Ludwig-Erhard-Allee 2, D-53175 Bonn (Germany)

    2010-07-01

    Compared to Ti-rich {gamma}-TiAl-based alloys Al-rich Ti-Al alloys offer an additional reduction of in density and a better oxidation resistance which are both due to the increased Al content. Polycrystalline material was manufactured by centrifugal casting. Microstructural characterization was carried out employing light-optical, scanning and transmission electron microscopy and XRD analyses. The high temperature creep of two binary alloys, namely Al{sub 60}Ti{sub 40} and Al{sub 62}Ti{sub 38} was comparatively assessed with compression tests at constant true stress in a temperature range between 1173 and 1323 K in air. The alloys were tested in the cast condition (containing various amounts of the metastable phases Al{sub 5}Ti{sub 3} and h-Al{sub 2}Ti) and after annealing at 1223 K for 200 h which produced (thermodynamically stable) lamellar {gamma}-TiAl + r-Al{sub 2}Ti microstructures. In general, already the as-cast alloys exhibit a reasonable creep resistance at 1173 K. Compared with Al{sub 60}Ti{sub 40}, both, the as-cast and the annealed Al{sub 62}Ti{sub 38} alloy exhibit better creep resistance up to 1323 K which can be rationalized by the reduced lamella spacing. The assessment of creep tests conducted at identical stress levels and varying temperatures yielded apparent activation energies for creep of Q = 430 kJ/mol for the annealed Al{sub 60}Ti{sub 40} alloy and of Q = 383 kJ/mol for the annealed Al{sub 62}Ti{sub 38} material. The latter coincides well with that of Al diffusion in {gamma}-TiAl, whereas the former can be rationalized by the instability of the microstructure containing metastable phases.

  16. MOSQUE ARCHITECTURE AS A SUSTAINABLE BUILDING IN URBAN (Case Study: Al Markas Al Islamic Mosque Makassar)

    OpenAIRE

    Imriyanti Imriyanti

    2014-01-01

    Abstract Mosque Architecture is a part of Islamic architecture. Mosque should be fused with elements of nature because its function as a place to pray to God who created the universe. Al Markas Al Islamic Makassar mosque is used as a center of Islamic aspirations of the people and the government to accommodate all the activities of moslems in Makassar. Through this function, the provision of Al Markas Al Islamic mosque began from the desire of Islamic societies in Makassar, which want...

  17. Corrosion Studies of 2195 Al-Li Alloy and 2219 Al Alloy with Differing Surface Treatments

    Science.gov (United States)

    Danford, M. D.; Mendrek, M. J.

    1998-01-01

    Corrosion studies of 2195 Al-Li and 2219 Al alloys have been conducted using the scanning reference electrode technique (SRET) and the polarization resistance (PR) technique. The SRET was used to study corrosion mechanisms, while corrosion rate measurements were studied with the PR technique. Plates of Al203 blasted, soda blasted and conversion coated 2219 Al were coated with Deft primer and the corrosion rates studied with the EIS technique. Results from all of these studies are presented.

  18. Japanese version of the ALS-FTD-Questionnaire (ALS-FTD-Q-J).

    Science.gov (United States)

    Watanabe, Yasuhiro; Beeldman, Emma; Raaphorst, Joost; Izumi, Yuishin; Yoshino, Hiide; Masuda, Michihito; Atsuta, Naoki; Ito, Satoru; Adachi, Tadashi; Adachi, Yoshiki; Yokota, Osamu; Oda, Masaya; Hanashima, Ritsuko; Ogino, Mieko; Ichikawa, Hiroo; Hasegawa, Kazuko; Kimura, Hideki; Shimizu, Toshio; Aiba, Ikuko; Yabe, Hayato; Kanba, Makoto; Kusumi, Kimiyoshi; Aoki, Tetsuya; Hiroe, Yu; Watanabe, Hirohisa; Nishiyama, Kazutoshi; Nomoto, Masahiro; Sobue, Gen; Nakashima, Kenji

    2016-08-15

    Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share common clinical, genetic and neuropathological features. Some ALS patients have behavioral/personality changes, which could result in significant obstacles in the care provided by family members and caregivers. An easy screening tool would contribute greatly to the evaluation of these symptoms. We translated the ALS-FTD-Questionnaire, developed in the Netherlands, into Japanese (ALS-FTD-Q-J) and examined the clinimetric properties (internal consistency, construct and clinical validity). Patients with ALS and/or behavioral variant FTD (bvFTD) were evaluated alongside healthy controls in this multicenter study. All ALS patients, regardless of bvFTD status, were further evaluated by the frontal behavioral inventory (FBI) and for frontal/executive function, cognition, anxiety/depression, and motor functions. Data from 146 subjects were analyzed: ALS (92), ALS-bvFTD (6), bvFTD (16), and healthy controls (32). The internal consistency of the ALS-FTD-Q-J was good (Cronbach α=0.92). The ALS-FTD-Q-J showed construct validity as it exhibited a high correlation with the FBI (r=0.79). However, correlations were moderate with anxiety/depression and low with cognitive scales, in contrast to the original report, i.e. a moderate correlation with cognition and a low correlation with anxiety/depression. The ALS-FTD-Q-J discriminated ALS patients from (ALS-)bvFTD patients and controls. Thus, the ALS-FTD-Q-J is useful for evaluating Japanese ALS/FTD patients. PMID:27423564

  19. Japanese version of the ALS-FTD-Questionnaire (ALS-FTD-Q-J).

    Science.gov (United States)

    Watanabe, Yasuhiro; Beeldman, Emma; Raaphorst, Joost; Izumi, Yuishin; Yoshino, Hiide; Masuda, Michihito; Atsuta, Naoki; Ito, Satoru; Adachi, Tadashi; Adachi, Yoshiki; Yokota, Osamu; Oda, Masaya; Hanashima, Ritsuko; Ogino, Mieko; Ichikawa, Hiroo; Hasegawa, Kazuko; Kimura, Hideki; Shimizu, Toshio; Aiba, Ikuko; Yabe, Hayato; Kanba, Makoto; Kusumi, Kimiyoshi; Aoki, Tetsuya; Hiroe, Yu; Watanabe, Hirohisa; Nishiyama, Kazutoshi; Nomoto, Masahiro; Sobue, Gen; Nakashima, Kenji

    2016-08-15

    Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share common clinical, genetic and neuropathological features. Some ALS patients have behavioral/personality changes, which could result in significant obstacles in the care provided by family members and caregivers. An easy screening tool would contribute greatly to the evaluation of these symptoms. We translated the ALS-FTD-Questionnaire, developed in the Netherlands, into Japanese (ALS-FTD-Q-J) and examined the clinimetric properties (internal consistency, construct and clinical validity). Patients with ALS and/or behavioral variant FTD (bvFTD) were evaluated alongside healthy controls in this multicenter study. All ALS patients, regardless of bvFTD status, were further evaluated by the frontal behavioral inventory (FBI) and for frontal/executive function, cognition, anxiety/depression, and motor functions. Data from 146 subjects were analyzed: ALS (92), ALS-bvFTD (6), bvFTD (16), and healthy controls (32). The internal consistency of the ALS-FTD-Q-J was good (Cronbach α=0.92). The ALS-FTD-Q-J showed construct validity as it exhibited a high correlation with the FBI (r=0.79). However, correlations were moderate with anxiety/depression and low with cognitive scales, in contrast to the original report, i.e. a moderate correlation with cognition and a low correlation with anxiety/depression. The ALS-FTD-Q-J discriminated ALS patients from (ALS-)bvFTD patients and controls. Thus, the ALS-FTD-Q-J is useful for evaluating Japanese ALS/FTD patients.

  20. Interfacial reactions in Al/Ni multilayers

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, F.; Greer, A.L. [Cambridge Univ. (United Kingdom). Dept. of Metallurgy and Materials Science

    1998-08-01

    In thin-film multilayers, the reactions at the interfaces can proceed quite differently from those in bulk samples because of the short diffusion distances involved. In the present work Al/Ni multilayers have been made by DC magnetron sputtering. The initial Ni and Al layers have strong (111) texture. The reactions taking place have been studied in relation to the layer thickness and film structure (grain size and texture). Also multilayers have been made with alloy layers Al/Ni(Al). Typically, differential scanning calorimetry shows a sequence of reactions on heating. X-ray diffraction, including texture goniometry, has been used to identify the compounds produced. In common with earlier work, it is found that Al{sub 3}Ni is the first phase to form, but the present results differ from those reported previously in that the Al{sub 3}Ni{sub 2} phase is not formed in the course of phase evolution. The difference from the earlier results is attributed to the sharper texture in the films in the present work. Thus it is concluded that for Al/Ni multilayers, reaction sequences can be affected by crystallographic orientation, as well as other factors. (orig.) 13 refs.