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Sample records for boophilus microplus increases

  1. 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

  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. 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

  4. 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,...

  5. 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,...

  6. 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

  7. 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.

  8. 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

  9. 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

  10. 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...

  11. 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...

  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

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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.

  13. 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.

  14. 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...

  15. 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...

  16. 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...

  17. 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

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

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    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

  19. 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

  20. 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...

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

    OpenAIRE

    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...

  2. 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...

  3. 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

  4. 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

  5. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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

  8. 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.

  9. 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 (...

  10. 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...

  11. 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...

  12. 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

  13. 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.

  14. 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...

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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

  20. 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

  1. 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...

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

    Science.gov (United States)

    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

  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. 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

  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

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    Alberto Gomes

    2011-08-01

    demonstrada aos distintos produtos testados sugere que a resistência do carrapato a diferentes classes esteja amplamente disseminada no Estado, motivo pelo qual recomenda-se a realização rotineira de testes de suscetibilidade antes da seleção e aplicação de produtos acaricidas para controle do carrapato.The cattle tick, Rhipicephalus (Boophilus microplus, is one of the most important ectoparasites of bovines, requiring adoption of control measures mainly in Bos taurus herds and its crossbreeds. Its control has becoming increasingly difficult due to selection of resistant populations by commercial products. This study aimed to know the status of cattle tick resistance to acaricides in the state of Mato Grosso do Sul. From October 2003 to October 2006 acaricide bioassays were conducted on cattle ticks from eleven of the most important livestock regions of the state. Adult immersion tests using regular commercial products according to label recommendations were followed by the evaluation of biological parameters. Twelve acaricide products containing one or more of seven active ingredients, from three chemical classes: amidine (amitraz, synthetic pyrethroid (cypermethrin, and organophosphates (chlorfenvinphos, chlorpyriphos, diazinon, dichlorvos, and ethion were tested. Low tick susceptibility was observed in all ranches, with several populations showing virtually no susceptibility to one or more products. Despite the great variation of susceptibility shown by the populations to each acaricide, a gradient of efficacy of these products was observed. Regardless of the acaricide class, the average efficacy of products containing a single active ingredient (19.94%-64.27% was generally lower than that showed by the mixtures, pyrethroid-organophosphate (46.38%-82.68% and between organophosphates (85.28%-97.68%. The mixture containing pyrethroid + OF + synergist + repellent (cypermethrin + chlorpyrifos + citronellal + piperonyl butoxide showed 100% efficacy, although it was

  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

    Directory of Open Access Journals (Sweden)

    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. [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

  3. 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

  4. 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

  5. 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

  6. 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.

  7. 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

  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

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    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

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    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

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    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. 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...

  15. 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...

  16. 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

  17. 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

  18. 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

  19. 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

    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

  20. 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

  1. 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

  2. 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)

  3. 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

  4. 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

  5. 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

  6. 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.

  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. 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

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

    Science.gov (United States)

    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

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

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    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.

  8. 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

  9. 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.

  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. 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

  12. 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

  13. 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...

  14. 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 ...

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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...

  12. 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

  13. 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.

  14. 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 ...

  15. 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...

  16. [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

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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

    Directory of Open Access Journals (Sweden)

    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

  4. 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

  5. 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...

  6. 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...

  7. 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 ...

  8. 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...

  9. 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

  10. 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

  11. 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

  12. 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

    Directory of Open Access Journals (Sweden)

    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

  13. 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

  14. 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.

  15. 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

  16. 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.

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

    Science.gov (United States)

    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

  18. 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

  19. 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

  20. 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

  1. 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.

  2. 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

    Full Text Available 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, received no treatment; II- treated with amitraz dip; III- treated with a standard commercial mixture of biotherapic 12cH, p.o. Group III presented a statistically significant decrease of ticks when compared to the control group (p Keywords: Biotherapic; Tick; Alternative control; Cattle.   Uso do bioterapico no controle da infestação natural por Boophilus microplus: estudo piloto Resumo No controle de enfermidades transmitidas por carrapatos tem sido notada a resistência a produtos químicos. A preocupação com a conservação do meio ambiente tem exigido procedimentos alternativos para controlar a infestação por Boophilus microplus, em todo o mundo. O uso de bioterápicos representa uma dessas alternativas. O objetivo deste estudo foi avaliar o efeito de uma mistura de bioterápicos incluindo B. microplus, em gado bovino infestado naturalmente. 27 animais foram divididos em 3 grupos (n=9: I controle sem tratamento; II tratado com banho de amitraz; III tratado com mistura comercial de bioterápicos 12 cH, via oral. O grupo III apresentou uma diminuição estatísticamente significativa de carrapatos, em comparação com grupo controle (p Palavras-chave: Bioterapicos; Carrapato; Controles alternativos; Bovinos.   Uso de bioterápico en el control de la infestación natural por Boophilus microplus: estudio piloto

  3. 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]). ...

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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.

  11. 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

  12. 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%.

  13. 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...

  14. 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

  15. 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.

  16. 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

  17. 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...

  18. 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.

  19. 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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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...

  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. 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.

  7. 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...

  8. 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...

  9. 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

    cattle tick Boophilus microplus (Canestrini, 1887 and to estimate genetic parameters for the level of this infestation. Countings of the parasite were done on female cattle from two herds, during all four seasons of the year, in two consecutive years (from September 1998 through July 2000. The number of ticks (NC on one side of the animal was counted, and the infestations were also evaluated by scores (EC, according to the estimated number of parasites on the animal. Each animal had from one to eight observations. A total of 4,079 and 3,994 observations were obtained for NC and EC, respectively. The data were analyzed by the least squares method with a model that included the effects of herd (H, color of the animal (C, H x C, animal within H x C as error a, year, season, thickness of the hair, and age of animal as a covariable (linear and quadratic effects. The variance and covariance components were estimated by the restricted maximum likelihood derivative free method, using a model that included the effects of contemporary group (herd - year - season, hair thickness and age of the animal as a covariable (linear and quadratic effects, and the random additive direct and permanent environmental effects. Before the analyses, NC was transformed to log10 (n + 1 and EC was transformed to (x + 0.5 ½, where n is the number of ticks counted on the animal and x is the score for EC (0 to 4. The incidence of ticks was higher during the summer, and the ticker the hair the higher the infestation. The heritability and repeatability estimates were equal to 0.22 and 0.29, and 0.15 and 0.21 for NC and EC, respectively, and the genetic correlation between NC and EC was 1.00. The results indicate that there is enough additive genetic variation on tick numbers to support a selection program to increase resistance.

  10. 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

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    Luísa N. Domingues

    2012-12-01

    maior parte das propriedades tende a comprometer não apenas a eficácia dos tratamentos, mas a suscetibilidade dos parasitos e a sustentabilidade do controle.The effective control of Haematobia irritans (horn fly and Rhipicephalus (Boophilus microplus (cattle tick is crucial for increasing the productivity of livestock industry in Brazil, but still remains a challenge. A greater knowledge about parasite control in the field is necessary to establish control strategies closer to farmer's reality and easier to be performed. This study characterized the practices adopted for controlling such ectoparasites on 23 cattle ranches from the Triângulo Mineiro and Alto Paranaíba region in the state of Minas Gerais, through interviews. Most interviewees recognized the importance of these parasites to livestock, however, many problems related to parasite control were observed. Control of horn flies and cattle tick was a routine in 17.4% and 95.7% of the ranches, respectively, triggered by high infestations on animals. More than six insecticide/acaricide treatments were applied yearly in all cattle ranches controlling horn flies and in 76.5% of the ranches controlling the cattle tick. Pesticide products were applied mostly by manual backpack sprayers (63.6% without restraining the animals in 45.5% of ranches. Product dilution following manufacturer's recommendations was performed by 45.5% of interviewees, but 63.6% of them used lower doses per animal than technically recommended. Associations of organophosphates and pyrethroids were the main products used to control both parasites. Although pesticide use was a routine practice, the use of personal protective equipment (PPE was not common among surveyed people. Most interviewees were able to recognize epidemiological characteristics of the parasites; however, parasite control measures adopted at most cattle ranches tend to jeopardize the efficacy of products, susceptibility of parasites and sustainability of control programs.

  11. [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

  12. 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

  13. 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.

  14. 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

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    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

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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

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

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    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.

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

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    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.

  10. 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.

  11. 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...

  12. 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...

  13. 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...

  14. 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

  15. 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.

  16. 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

  17. 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

  18. 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 ...

  19. 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 ...

  20. 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

  1. 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...

  2. 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...

  3. 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

  4. 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...

  5. 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.

  6. 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.

  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. 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.

  10. 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.

  11. 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

  12. 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...

  13. 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

  14. 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

  15. 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

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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...

  6. 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.

  7. 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 ...

  8. 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

  9. 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

  10. 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

  11. 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

  12. 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

  13. 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...

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

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    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.

  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

    Full Text Available Este trabalho tem como objetivo avaliar a viabilidade econômica do programa de controle estratégico do carrapato em bovinos leiteiros adotado pela Embrapa Gado de Leite. O programa se fundamenta na racionalização do uso de carrapaticidas com a realização de tratamentos no período em que a população de carrapatos encontra-se reduzida; na escolha do produto mais adequado para o combate da população de carrapatos, por meio da realização de testes de sensibilidade dos carrapatos aos carrapaticidas; e, pela utilização do carrapaticida na diluição recomendada e quantidade suficiente para banhar todo o corpo do animal. O estudo foi realizado junto a 104 produtores rurais, criadores de gado de leite, em 27 municípios da região central e norte do estado de Minas Gerais. As informações foram coletadas por meio de questionário, no período de setembro a novembro de 2010. Constatou-se que em 68% dos rebanhos, a infestação por TPB é a que mais afeta os animais. Por causa desse e outros problemas, 79% dos consultados resolveram aderir ao Programa por recomendação do técnico e outros 70% por causa das altas infestações nos animais. Setenta e nove por cento aderiram e seguiram o Programa, de maneira correta. Nessas fazendas, a maior parte da mão de obra é contratada (46%, o sistema de exploração da atividade leiteira é o semi-intensivo (84%, o padrão racial do rebanho é o cruzamento Girolando (95% e em, 45%, a produção média diária de leite varia entre 40 a 400 litros. Antes da adesão ao Programa, em 89% das propriedades, as vacas lactantes eram as mais afetadas, seguidas de bezerros. Para escolher o carrapaticida, 41% dos produtores baseavam a escolha na indicação do balconista. Após a adesão ao Programa, 94% dos fazendeiros seguiram as orientações repassadas pelos técnicos. O primeiro motivo citado (78% para permanência com o plano de controle foi a credibilidade no teste de sensibilidade dos carrapatos aos 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. 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...

  17. 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...

  18. 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.

  19. 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 ...

  20. 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

  1. 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...

  2. 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

  3. 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.

  4. 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...

  5. 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.

  6. 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

  7. 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.

  8. 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...

  9. 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...

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

    Directory of Open Access Journals (Sweden)

    Fernanda Ferreira Pessoa

    2012-12-01

    chamber and necklace did not affect the cortisol level, although they had prevented grooming. Consequently, animals with the artifacts had more ticks than the ones with no artifacts (34.56% versus 14.9% tick recovery rate, P< 0.05. The last blood sample collection had revealed an increase on the cortisol level, coinciding with the final parasitic life cycle of R. microplus (Table 1. No significant correlation were detected between cortisol levels and the tick recovery rate. Grooming is important to decrease the cattle tick infestation, but its limitation presented in this study, did not elevate the serum cortisol level, related to animal stress.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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

  16. 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.

  17. 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

  18. 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

  19. 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

  20. 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

  1. 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...

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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.

  8. 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 ...

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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...

  14. 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

  15. 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

  16. 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

  17. 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.

  18. 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

  19. 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...

  20. 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...

  1. 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

  2. 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 ...

  3. 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.

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

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    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.

  5. 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 ...

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

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    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.

  7. 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

  8. 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

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

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    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

  10. 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

  11. 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

  12. 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.

  13. 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...

  14. 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

  15. 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.

  16. 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...

  17. Eosinophils increase in animals that received biotherapic

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    Pedro Gilberto Silva Morais

    2012-12-01

    Full Text Available Dairy industry is an important Brazilian economic activity participating of income generation. European breeds cattle aren’t adapted to parasites found in the tropics, like the Rhipicephalus microplus tick. Parasites can acquire resistance to allopathic products, but not to homeopathic products. We evaluate the efficacy of an antiparasiticide biotherapic against the R. microplus tick. The biotherapic was prepared according to the homeopathic pharmacopoeia recommendations from vegetable (Abrotanum and animal products (Rhipicephalus microplus, Amblyomma cajenennense, Haematobia irritans, Musca domestica, Dermatobia hominis, all diluted and vigorous shaken (dynamized in water or alcohol at a ratio of 1:99, in the 12th Centesimal Hahnemann (CH12, with limestone as the carrier. This homeophatic product found in veterinary pharmacies of Ituiutaba’s region, Minas Gerais State, is registered at Ministério da Agricultura, Pecuária e Abastecimento (MAPA. Natural tick infestation was accessed in thirty Girolando (Gir x Holstein cows with 7 to 13 year-old, by monthly counting of tick female bigger than 6 mm, from October/2009 to July/2011. Cows were divided in three groups of 10 similar animals. The treated group (T1 received roughage, concentrate and biotherapic. The placebo group (T2 received roughage, concentrate and limestone and the control group (T3 received only roughage and concentrate. T1 and T2 groups were managed together and remained in the same paddock. T3 group was separed from T1 and T2 by a wire fence. From October 2009 to September 2010 blood cell counts and serum biochemical tests were performed monthly only in T1 and T2, but visual clinical observations were made in all animals. Any group was treated with acaricide when the count’s average reached 50 or more ticks. It was necessary 7 baths with acaricide in T1 and T2, while in T3 group (control group it was necessary 19 acaricide baths to control the cattle tick. We verified

  18. 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.

  19. 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

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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...

  7. Cattle tick-associated bacteria exert anti-biofilm and anti-Tritrichomonas foetus activities.

    Science.gov (United States)

    Zimmer, K R; Seixas, A; Conceição, J M; Zvoboda, D A; Barros, M P; Tasca, T; Macedo, A J; Termignoni, C

    2013-05-31

    Research on microbiota in cattle tick and the evaluation of its activity against other microorganisms can contribute to identify new molecules potentially useful to control infections caused by bacteria and protozoa. Biofilms pose increasing problems worldwide, mainly due to their resistance to antimicrobial therapies and host immune response. In this study we investigate the ability Rhipicephalus (Boophilus) microplus-associated bacteria may exhibit to produce anti-biofilm and trichomonicidal compounds. Gut, ovary, salivary glands, and Gené organ were collected from engorged R. microplus female. Homogenates of each tissue were inoculated onto 15 distinct culture media. Anti-biofilm and trichomonicidal activities were analyzed by culturing each bacterium isolated in a liquid medium. Results showed that R. microplus cattle tick microflora varies for different tissues. Bacteria belonging to different genera (Aeromonas, Bacillus, Brevibacillus, Castelaniella, Comamonas, Kocuria, and Microbacterium) were identified. Interestingly, all bacterial species found displayed pronounced activity against Staphylococcus epidermidis and Pseudomonas aeruginosa biofilms, and also against the cattle pathogen Tritrichomonas foetus, confirming the hypothesis that cattle tick could be a source of bacteria active against pathogens. This is the first study showing that bacteria isolated from a tick exert anti-biofilm and trichomonicidal activities. PMID:23434012

  8. 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

  9. 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...

  10. 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...

  11. 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...

  12. Assessment of Acute Oral and Dermal Toxicity of 2 Ethyl-Carbamates with Activity against Rhipicephalus microplus in Rats

    Directory of Open Access Journals (Sweden)

    María Guadalupe Prado-Ochoa

    2014-01-01

    Full Text Available The acute oral and dermal toxicity of two new ethyl-carbamates (ethyl-4-bromophenyl-carbamate and ethyl-4-chlorophenyl-carbamate with ixodicide activity was determined in rats. The oral LD50 of each carbamate was 300 to 2000 mg/kg, and the dermal LD50 of each carbamate was >5000 mg/kg. Clinically, the surviving rats that had received oral doses of each carbamate showed decreased weight gain (P<0.05 and had slight nervous system manifestations. These clinical signs were evident from the 300 mg/kg dose and were reversible, whereas the 2000 mg/kg dose caused severe damage and either caused their death or was motive for euthanasia. At necropsy, these rats had dilated stomachs and cecums with diffuse congestion, as well as moderate congestion of the liver. Histologically, the liver showed slight degenerative lesions, binucleated hepatocytes, focal coagulative necrosis, and congestion areas; the severity of the lesions increased with dosage. Furthermore, an slight increase in gamma-glutamyltransferase, lactate dehydrogenase, and creatinine was observed in the plasma. The dermal application of the maximum dose (5000 mg/kg of each carbamate did not cause clinical manifestations or liver and skin alterations. This finding demonstrates that the carbamates under study have a low oral hazard and low acute dermal toxicity.

  13. The impact of 2 dipping systems on endemic stability to bovine babesiosis and anaplasmosis in cattle in 4 communally grazed areas in Limpopo Province, South Africa

    Directory of Open Access Journals (Sweden)

    B.O. Rikhotso

    2005-06-01

    Full Text Available A 12-month study was conducted in 4 communal grazing areas in the Bushbuckridge region, Limpopo Province, South Africa. The main objective was to investigate the impact of reduced acaricide application on endemic stability to bovine babesiosis (Babesia bigemina and Babesia bovis and anaplasmosis (Anaplasma marginale in the local cattle population. To this end 60 cattle in each communal grazing area were bled at the beginning and the conclusion of the experimental period and their sera were assayed for B. bovis, B. bigemina and Anaplasma antibodies. Cattle in the intensively dipped group were dipped 26 times and maintained on a 14-day dipping interval throughout the study, whereas cattle in the strategically dipped group were dipped only 13 times. Three cattle, from which adult ticks were collected, were selected from each village, while immature ticks were collected by drag-sampling the surrounding vegetation. During the dipping process, a questionnaire aimed at assessing the prevalence of clinical cases of tick-borne disease, abscesses and mortalities was completed by an Animal Health Technician at each diptank. An increase in seroprevalence to B. bovis and B. bigemina and a decrease in seroprevalence to Anaplasma was detected in the strategically dipped group while in the intensively dipped group the converse was true. Amblyomma hebraeum was the most numerous tick species on the cattle, and Rhipicephalus (Boophilus microplus was more plentiful than Rhipicephalus (Boophilus decoloratus. Drag samples yielded more immature stages of A. hebraeum than of Rhipicephalus (Boophilus spp. The incidence of clinical cases of tick-borne disease and of abscesses increased in the strategically dipped group at the start of the survey.

  14. Price increase

    CERN Multimedia

    2006-01-01

    Please take note that after five years of stable prices at Restaurant No 1 a price increase will come into force on 1st January 2006. This increase has been agreed after discussions between the CSR (Comité de Surveillance des Restaurants) and the catering company Novae and will reflect the inflation rate of the last few years. In addition, a new children's menu will be introduced, as well as 'Max Havelaar' fair-trade coffee at a price of 1.70 CHF.

  15. Price increase

    CERN Multimedia

    2005-01-01

    Please take note that after five years of stable prices at Restaurant No 1 a price increase will come into force on 1st January 2006. This increase has been agreed after discussions between the CSR (Comité de Surveillance des Restaurants) and the catering company Novae and will reflect the inflation rate of the last few years. In addition, a new children's menu will be introduced as well as 'Max Havelaar' fair-trade coffee at a price of 1.70 CHF.

  16. 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

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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 ...

  5. 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...

  6. 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

  7. Ixodidas brasileiros e de alguns paizes limitrophes

    Directory of Open Access Journals (Sweden)

    Henrique de Beaurepaire Aragão

    1936-01-01

    Full Text Available The knowledge of the Ixodidae becomes every day, more and more important owing to the fact of the increasing number of diseases of man and animals they can transmit. In Brasil besides transmitting treponemosis, piroplasmosis and anaplasmosis to several domestic animals, the ticks are also responsible fo the transmission of the brazilian rocky mountain spotted fever (A. cajennense and Amblyomma striatum and they can also harbour the virus of the yellow fever and even to transmit it in laboratory experiments (A. cajennense, O. rostratus. The Brazilian fauna of ticks is a small one and has no more than 45 well-established species belonging to the genus Argas, Ornithodoros, Ixodes, Haemaphysalis, Rhipicephalus, Boophilus, Amblyomma and Spaelaeorhynchus. The genus Amblyomma is the best represented one, with 67% of all species of ticks known in Brazil. One of the most important species in the Amblyomma cajennense owing to its abundance and its wide parasitism in many vertebrates: reptiles, birds and mammals, incluing man, who is much attacked by the larva, the nymph and the adult of this species. The other ticks who attack the man are the Amblyomma brasiliense (the pecari tick, in the forests, and the Ornithodoros, especially the species. O. rostratus and brasiliensis. Other species can bite the man, but only occasionally, like Amblyomma fossum, striatum, oblongogutatum etc. Argas persicus, Rhipicephalus sanguineus and Boophilus are very important species not only as parasites but specially because they transmit several diseases to animals. Some of the ticks of the brazilian wild animals are now also parasites of the domestic ones and vice-versa. Arga persicus var. dissimilis is very common among the poultry and transmits the Treponema anserinum (gallinarum. Boophilus microplus is very abundant on our domestic and wild ruminants (Bos, Cervus, Mazama etc. and can also ben found on horse, dogs, Felis onca, Felis concolor etc., and it transmits to cattle

  8. ATP Binding Cassette Transporter Mediates Both Heme and Pesticide Detoxification in Tick Midgut Cells.

    Science.gov (United States)

    Lara, Flavio Alves; Pohl, Paula C; Gandara, Ana Caroline; Ferreira, Jessica da Silva; Nascimento-Silva, Maria Clara; Bechara, Gervásio Henrique; Sorgine, Marcos H F; Almeida, Igor C; Vaz, Itabajara da Silva; Oliveira, Pedro L

    2015-01-01

    In ticks, the digestion of blood occurs intracellularly and proteolytic digestion of hemoglobin takes place in a dedicated type of lysosome, the digest vesicle, followed by transfer of the heme moiety of hemoglobin to a specialized organelle that accumulates large heme aggregates, called hemosomes. In the present work, we studied the uptake of fluorescent metalloporphyrins, used as heme analogs, and amitraz, one of the most regularly used acaricides to control cattle tick infestations, by Rhipicephalus (Boophilus) microplus midgut cells. Both compounds were taken up by midgut cells in vitro and accumulated inside the hemosomes. Transport of both molecules was sensitive to cyclosporine A (CsA), a well-known inhibitor of ATP binding cassette (ABC) transporters. Rhodamine 123, a fluorescent probe that is also a recognized ABC substrate, was similarly directed to the hemosome in a CsA-sensitive manner. Using an antibody against conserved domain of PgP-1-type ABC transporter, we were able to immunolocalize PgP-1 in the digest vesicle membranes. Comparison between two R. microplus strains that were resistant and susceptible to amitraz revealed that the resistant strain detoxified both amitraz and Sn-Pp IX more efficiently than the susceptible strain, a process that was also sensitive to CsA. A transcript containing an ABC transporter signature exhibited 2.5-fold increased expression in the amitraz-resistant strain when compared with the susceptible strain. RNAi-induced down-regulation of this ABC transporter led to the accumulation of metalloporphyrin in the digestive vacuole, interrupting heme traffic to the hemosome. This evidence further confirms that this transcript codes for a heme transporter. This is the first report of heme transport in a blood-feeding organism. While the primary physiological function of the hemosome is to detoxify heme and attenuate its toxicity, we suggest that the use of this acaricide detoxification pathway by ticks may represent a new

  9. ATP Binding Cassette Transporter Mediates Both Heme and Pesticide Detoxification in Tick Midgut Cells.

    Directory of Open Access Journals (Sweden)

    Flavio Alves Lara

    Full Text Available In ticks, the digestion of blood occurs intracellularly and proteolytic digestion of hemoglobin takes place in a dedicated type of lysosome, the digest vesicle, followed by transfer of the heme moiety of hemoglobin to a specialized organelle that accumulates large heme aggregates, called hemosomes. In the present work, we studied the uptake of fluorescent metalloporphyrins, used as heme analogs, and amitraz, one of the most regularly used acaricides to control cattle tick infestations, by Rhipicephalus (Boophilus microplus midgut cells. Both compounds were taken up by midgut cells in vitro and accumulated inside the hemosomes. Transport of both molecules was sensitive to cyclosporine A (CsA, a well-known inhibitor of ATP binding cassette (ABC transporters. Rhodamine 123, a fluorescent probe that is also a recognized ABC substrate, was similarly directed to the hemosome in a CsA-sensitive manner. Using an antibody against conserved domain of PgP-1-type ABC transporter, we were able to immunolocalize PgP-1 in the digest vesicle membranes. Comparison between two R. microplus strains that were resistant and susceptible to amitraz revealed that the resistant strain detoxified both amitraz and Sn-Pp IX more efficiently than the susceptible strain, a process that was also sensitive to CsA. A transcript containing an ABC transporter signature exhibited 2.5-fold increased expression in the amitraz-resistant strain when compared with the susceptible strain. RNAi-induced down-regulation of this ABC transporter led to the accumulation of metalloporphyrin in the digestive vacuole, interrupting heme traffic to the hemosome. This evidence further confirms that this transcript codes for a heme transporter. This is the first report of heme transport in a blood-feeding organism. While the primary physiological function of the hemosome is to detoxify heme and attenuate its toxicity, we suggest that the use of this acaricide detoxification pathway by ticks may

  10. 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.

  11. Tick fauna from two locations in the Brazilian savannah.

    Science.gov (United States)

    Szabó, Matias Pablo Juan; Olegário, Maria Marlene Martins; Santos, André Luiz Quagliatto

    2007-01-01

    The Cerrado is Brazil's tropical savannah, which is arguably under greater threat than the Amazon rainforest. The Cerrado Biome of tropical South America covers about 2 million km(2) and is considered a biodiversity hot spot which means that it is especially rich in endemic species and particularly threatened by human activities. The Cerrado is increasingly exposed to agricultural activities which enhance the likelihood of mixing parasites from rural, urban and wildlife areas. Information about ticks from the Cerrado biome is scarce. In this report tick species free-living, on domestic animals and on a few wild animals in two farms in the Cerrado biome (Nova Crixás and Araguapaz municipalities, Goiás State, Brazil) are described. Amblyomma cajennense was the first and Amblyomma parvum the second host-seeking tick species found. Only two other tick species were found free-living: one Amblyomma nodosum and three Amblyomma naponense nymphs. Cattle were infested with Boophilus microplus and A. cajennense. Buffalos were infested with B. microplus and A. parvum. Dogs were infested with A. cajennense, Amblyomma ovale, A. parvum and Rhipicephalus sanguineus ticks. Anocentor nitens, B. microplus, A. cajennense, and A. parvum were found on horses. Amblyomma auricularium were found attached to nine-banded armadillos and Amblyomma rotundatum to red-footed tortoise, cururu toads and a rattlesnake. The latter was also infested with an adult A. cajennense. No tick was found on a goat, a tropical rat snake and a yellow armadillo. Among the observations the infestation of several domestic animals with A. parvum seems be the main feature. It suggests that this species might become a pest. However, the life cycle of A. parvum in nature, as well as its disease vectoring capacity, are largely unknown. It would be important to determine if it is a species expanding its geographic range by adaptation to new hosts or if it has been maintained in high numbers at definite locations by

  12. Increases in Problem Drinking

    Science.gov (United States)

    ... Increases in Problem Drinking Join the Fight Against Superbugs Featured Website: Genetic and Rare Diseases Information Center ... Increases in Problem Drinking Join the Fight Against Superbugs Featured Website: Genetic and Rare Diseases Information Center ...

  13. Effect of increased

    NARCIS (Netherlands)

    Carreira , C.; Heldal, M.; Bratbak, G.

    2013-01-01

    Atmospheric carbon dioxide (CO2) has increased since the pre-industrial period and is predicted to continue to increase throughout the twenty-first century. The ocean is a sink for atmospheric CO2 and increased CO2 concentration will change the carbonate equilibrium of seawater and result in lower c

  14. Impact of Babesia bovis and Babesia bigemina on the production of beef cattle in Uruguay.

    Science.gov (United States)

    Solari, M A; Nari, A; Cardozo, H

    1992-01-01

    Uruguay is situated in a marginal area for the development of Boophilus microplus (30 degrees 35 degrees South Lat.) with important areas of enzootic instability for Babesia bovis and B. bigemina. The livestock products represent 70% of our exports, for which 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 babesiosis in the reduction of liveweight gains. The results are shown and discussed in the work. Experiment I: the weight increase of the control group (x = 0.248 kg/day), was 23% higher than that of the infected group with Babesia spp (from Uruguay), but significant statistical differences were not found (P pastures. The control group obtained x = 25.29 kg of liveweight gain and it was 45% higher than that of the infected group, significant statistical difference were found (P < 0.05). Experiments with attenuated strains III: four studies were carried out inoculating B. bovis and B. bigemina in bovines about one year old, in different growth systems, searching for the limit of application. Significant statistical differences between those groups were not found during the experiment (about 180 days) (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1343684

  15. A ten-year review of commercial vaccine performance for control of tick infestations on cattle.

    Science.gov (United States)

    de la Fuente, José; Almazán, Consuelo; Canales, Mario; Pérez de la Lastra, José Manuel; Kocan, Katherine M; Willadsen, Peter

    2007-06-01

    Ticks are important ectoparasites of domestic and wild animals, and tick infestations economically impact cattle production worldwide. Control of cattle tick infestations has been primarily by application of acaricides which has resulted in selection of resistant ticks and environmental pollution. Herein we discuss data from tick vaccine application in Australia, Cuba, Mexico and other Latin American countries. Commercial tick vaccines for cattle based on the Boophilus microplus Bm86 gut antigen have proven to be a feasible tick control method that offers a cost-effective, environmentally friendly alternative to the use of acaricides. Commercial tick vaccines reduced tick infestations on cattle and the intensity of acaricide usage, as well as increasing animal production and reducing transmission of some tick-borne pathogens. Although commercialization of tick vaccines has been difficult owing to previous constraints of antigen discovery, the expense of testing vaccines in cattle, and company restructuring, the success of these vaccines over the past decade has clearly demonstrated their potential as an improved method of tick control for cattle. Development of improved vaccines in the future will be greatly enhanced by new and efficient molecular technologies for antigen discovery and the urgent need for a tick control method to reduce or replace the use of acaricides, especially in regions where extensive tick resistance has occurred. PMID:17692140

  16. The quest for a universal vaccine against ticks: cross-immunity insights.

    Science.gov (United States)

    Parizi, Luís F; Githaka, Naftaly W; Logullo, Carlos; Konnai, Satoru; Masuda, Aoi; Ohashi, Kazuhiko; da Silva Vaz, Itabajara

    2012-11-01

    As blood-sucking parasites, ticks inflict great damage to animals and humans in many parts of the world. The continued use of chemical acaricides is not sustainable due to increasing tick resistance, growing public concern over drug residues in food and in the environment, and the high cost of developing new acaricides. Therefore, an alternative control strategy is urgently needed. Vaccines against ticks have been shown to be functionally feasible, as highlighted by the success of Bm86 vaccines against Rhipicephalus (Boophilus) microplus and closely related tick species. However, a limited number of tick antigens with cross-protective epitopes have been characterized so far, limiting widespread deployment of the available vaccines, including those derived from Bm86. Therefore, identifying tick antigens with potential broad-spectrum protection against multiple tick species is subject of vigorous research at present. In this paper, progress towards effective anti-tick vaccines is reviewed in the light of emerging data from studies including heterologous tick challenge. Taken together, these studies indicate that the decades-long search for a universal tick vaccine is making progress, with such a vaccine likely to be based on multiple cross-reactive antigens. PMID:22766309

  17. Increasing SLEDed Linac Gradient

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, Zoltan D

    2001-11-08

    This note will show how to increase the SLED [1] gradient by varying Q{sub e}, the external Q of the SLED cavity, by increasing its Q{sub 0} and by increasing the compression ratio. If varying the external Q is to be effective, then the copper losses should be small so that Q{sub 0} >> Q{sub e}. Methods of varying Q{sub e} will be indicated but no experimental data will be presented. If we increase the klystron pulse width from 3.5 to 5 {micro}S and increase Q{sub 0} from the present 100000 to 300000, then the gradient increases by 19% and the beam energy increases from 50 to 60 GeV. This note will also discuss SLED operation at 11424 MHz, the NLC frequency. Without Q{sub e} switching, using SLED at 11424 MHz increases the SLAC gradient from 21 MV/m to 34 MV/m, and at the same repetition rate, uses about 1/5 of rf average power. If we also double the compression ratio, we reach 47 MV/m and over 100 GeV beam energy.

  18. Increasing productivity: Another approach

    Energy Technology Data Exchange (ETDEWEB)

    Norton, F.J.

    1996-06-10

    An engineering information (EI) and information technology (IT) organization that must improve its productivity should work to further its business goals. This paper explores a comprehensive model for increasing EI/IT productivity by supporting organizational objectives.

  19. Increasing hygiene productivity.

    Science.gov (United States)

    Levin, Roger P

    2003-03-01

    Dentists have many opportunities to expand the role of dental hygienists and provide patients with better oral health care, while increasing production and profits. But the proper business systems and verbal skills need to be incorporated. You must train hygienists to do all they can do for every patient. Begin with one service and add others, as the hygienists becomes familiar with each one. Set a goal of a 15% increase in production per year for the hygiene department. Clinicians using these strategies have experienced as much as a 100% to 200% increase in hygiene revenue during the first year of incorporating these services. An added benefit is that these dentists often see a substantial increase in dental treatment diagnosis and case acceptance. An effective and efficient hygiene department will often identify and help secure more than 50% of a doctor's production.

  20. Increasing Public Library Productivity.

    Science.gov (United States)

    Samuelson, Howard

    1981-01-01

    Suggests ways of improving productivity for public libraries faced with increased accountability, dwindling revenues, and continuing inflation. Techniques described include work simplification, work analysis, improved management, and employee motivation. (RAA)

  1. 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.

  2. Exploding Increase of Population

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.H. [Sunmoon University, Chonan (Korea)

    2002-03-01

    Until 1650, the population of the world did not increase properly. According to studies of the demography, the annual increase rate of the world population during 2500 years, from 850 B.C. to 1650 A.D., was just 0.07%. Currently, however, the world population, which has exceptionally rapidly increased from 1900, is more than 6 billion as of 2000. After World War II, especially, the increase rate of the population has risen to about 1.8%, so we can use the word, explosion of the population. The explosion of the population accompanies the increase of energy consumption. The energy production of every year cannot sufficiently meet the energy demand, so we can face the grand energy crisis someday. The date might be a someday after 2020. According to the future forecasting of Shell, one of the majors, the peak of oil supply will be between 2015 and 2020. Unless the alternative energy is developed, the whole world will suffer the serious oil crisis.

  3. 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.

  4. 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.

  5. Seismic waves increase permeability.

    Science.gov (United States)

    Elkhoury, Jean E; Brodsky, Emily E; Agnew, Duncan C

    2006-06-29

    Earthquakes have been observed to affect hydrological systems in a variety of ways--water well levels can change dramatically, streams can become fuller and spring discharges can increase at the time of earthquakes. Distant earthquakes may even increase the permeability in faults. Most of these hydrological observations can be explained by some form of permeability increase. Here we use the response of water well levels to solid Earth tides to measure permeability over a 20-year period. At the time of each of seven earthquakes in Southern California, we observe transient changes of up to 24 degrees in the phase of the water level response to the dilatational volumetric strain of the semidiurnal tidal components of wells at the Piñon Flat Observatory in Southern California. After the earthquakes, the phase gradually returns to the background value at a rate of less than 0.1 degrees per day. We use a model of axisymmetric flow driven by an imposed head oscillation through a single, laterally extensive, confined, homogeneous and isotropic aquifer to relate the phase response to aquifer properties. We interpret the changes in phase response as due to changes in permeability. At the time of the earthquakes, the permeability at the site increases by a factor as high as three. The permeability increase depends roughly linearly on the amplitude of seismic-wave peak ground velocity in the range of 0.21-2.1 cm s(-1). Such permeability increases are of interest to hydrologists and oil reservoir engineers as they affect fluid flow and might determine long-term evolution of hydrological and oil-bearing systems. They may also be interesting to seismologists, as the resulting pore pressure changes can affect earthquakes by changing normal stresses on faults. PMID:16810253

  6. Does salt increase thirst?

    Science.gov (United States)

    Leshem, Micah

    2015-02-01

    Our diet is believed to be overly rich in sodium, and it is commonly believed that sodium intake increases drinking. Hence the concern of a possible contribution of dietary sodium to beverage intake which in turn may contribute to obesity and ill health. Here we examine whether voluntary, acute intake of a sodium load, as occurs in routine eating and snacking, increases thirst and drinking. We find that after ingesting 3.5 or 4.4 g NaCl (men) and 1.9 or 3.7 g (women) on nuts during 15 minutes, there is no increase in thirst or drinking of freely available water in the following 2 h compared with eating similar amounts of sugared or unflavored nuts. This suggests that routine ingestion of boluses of salt (~30-40% of daily intake for men, ~ 20-40% for women) does not increase drinking. Methodological concerns such as about nuts as vehicle for sodium suggest further research to establish the generalizability of this unexpected result. PMID:25447020

  7. Increased urinary orosomucoid excretion

    DEFF Research Database (Denmark)

    Christiansen, M S; Iversen, K; Larsen, C T;

    2009-01-01

    OBJECTIVE: In a previous study, urinary orosomucoid excretion rate (UOER) independently predicted cardiovascular mortality in patients with type 2 diabetes. The aim of the present study was to determine whether increased UOER is associated with cardiovascular risk factors such as inflammation, im...

  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. 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)...

  10. 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...

  11. 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

  12. 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...

  13. 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...

  14. 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.

  15. Increasing income inequality

    DEFF Research Database (Denmark)

    Frederiksen, Anders; Poulsen, Odile

    In recent decades most developed countries have experienced an increase in income inequality. In this paper, we use an equilibrium search framework to shed additional light on what is causing an income distribution to change. The major benefit of the model is that it can accommodate shocks...... to the skill composition in the market, employee bargaining power and productivity. Further, when our model is subjected to skill-upgrading and changes in employee bargaining power, it is capable of predicting the recent changes observed in the Danish income distribution. In addition, the model emphasizes...... that shocks to the employees' relative productivity, i.e., skill-biased technological change, are unlikely to have caused the increase in income inequality....

  16. Pemex increasing offshore activity

    Energy Technology Data Exchange (ETDEWEB)

    Beachy, D.

    1985-05-01

    Although austere by boom-year standards, Mexico's National Energy Program for 1984-1988 calls for forty wildcats and 90 to 144 development wells off the coast, primarily in the prolific Campeche Bay area. Platform additions will include nine drilling platforms, each for twelve wells, and eight eight platforms to drill injection wells. Additionally, 7 production, 6 accomodation, 6 linkage and 8 compression platforms and 13 tetrapods will be installed. The main objectives of the plan are energy self-sufficiency through the turn of the century, and energy diversification, savings and productivity. The most controversial portion of Mexico's energy program is that calling for nuclear energy development. The energy program lists three basic goals in hydrocarbon production: continuing research on better techniques of secondary recovery; increasing capacity for refining primary and secondary crude products and improving production of heavy crudes; and increasing storage capacity and installing pipelines capable of carrying a greater volume of crude.

  17. High population increase rates.

    Science.gov (United States)

    1991-09-01

    In addition to its economic and ethnic difficulties, the USSR faces several pressing demographic problems, including high population increase rates in several of its constituent republics. It has now become clear that although the country's rigid centralized planning succeeded in covering the basic needs of people, it did not lead to welfare growth. Since the 1970s, the Soviet economy has remained sluggish, which as led to increase in the death and birth rates. Furthermore, the ideology that held that demography could be entirely controlled by the country's political and economic system is contradicted by current Soviet reality, which shows that religion and ethnicity also play a significant role in demographic dynamics. Currently, Soviet republics fall under 2 categories--areas with high or low natural population increase rates. Republics with low rates consist of Christian populations (Armenia, Moldavia, Georgia, Byelorussia, Russia, Lithuania, Estonia, Latvia, Ukraine), while republics with high rates are Muslim (Tadzhikistan, Uzbekistan, Turkmenistan, Kirgizia, Azerbaijan Kazakhstan). The later group has natural increase rates as high as 3.3%. Although the USSR as a whole is not considered a developing country, the later group of republics fit the description of the UNFPA's priority list. Another serious demographic issue facing the USSR is its extremely high rate of abortion. This is especially true in the republics of low birth rates, where up to 60% of all pregnancies are terminated by induced abortions. Up to 1/5 of the USSR's annual health care budget is spent on clinical abortions -- money which could be better spent on the production of contraceptives. Along with the recent political and economic changes, the USSR is now eager to deal with its demographic problems. PMID:12284289

  18. Increase in family allowances.

    Science.gov (United States)

    1989-01-01

    In July 1989 the family allowance structure in Australia was changed from a 4-rate to a 2-rate structure. The new rates were increased to $A9 a week for the 1st 3 children and $A12 for each additional child. The Family Allowance Supplment rate for children 13-15 years old was raised from $A31 to $A34.10/week. PMID:12344544

  19. Market Expects Demand Increase

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In the recent releasing Textile Industry Invigorating Plan,"givingattention to both domestlc and overseas markets"is put into a keyposition.Under a series policies,such as increasing the tax rebaterate for textile and garment exports,and granting loan for SME,thefurther development of this industry is expectative.Otherwise,weshould know that it costs time for demand driving.This need ourpatients.The only questionis how much time we have to wait.

  20. Increasing student success

    Science.gov (United States)

    Stewart, Gay; Stewart, John

    2013-03-01

    A more scientifically literate society benefits all STEM disciplines, as well as society as a whole. It is best realized by better serving all undergraduate STEM students. In better-serving all students, a physics department also benefits. The University of Arkansas, Fayetteville physics department has seen a drastic change in number of majors, the number of students active in research and the number of graduates pursuing graduate work, while also increasing the number of majors who decide to teach. Prior to our involvement with the Physics Teacher Education Coalition, graduation rates had increased by more than a factor of 4 in 4 years. After the increased efforts when we became a part of PhysTEC (http://PhysTEC.org) our graduation numbers doubled again. Specific attention to class policy to impact student learning in our introductory courses and strong preparation of the graduate teaching assistants, and quality advising were our primary areas of emphasis. What worked to build these numbers and strengthen these resources at Arkansas will be discussed. This work was supported in part by the National Science Foundation and through the Physics Teacher Education Coalition.

  1. Condom use increasing.

    Science.gov (United States)

    Finger, W R

    1998-01-01

    Condom use is central to the prevention of AIDS among people at risk for contracting HIV. As such, condom use is increasing dramatically even though many men say that they do not like using them. Condom sales through social marketing campaigns have increased dramatically in some countries, where tens of millions of condoms are sold annually. For example, during the period 1991-96, annual social marketing sales increased about five-fold in Ethiopia to 21 million, and nine-fold in Brazil to 27 million. These sales reflect the success of condom social marketing campaigns in making condoms accessible and largely affordable. There is also a greater general awareness of AIDS than there used to be, and communication campaigns have shown that condoms are an effective solution. More condoms still need to be used in the ongoing struggle against HIV/AIDS. The author discusses the factors which affect the limited acceptance of condoms, condom use outside of marriage, social marketing, and family planning programs. PMID:12293530

  2. Alarming increase in refugees.

    Science.gov (United States)

    1992-01-01

    Over the past decade and half there has been an alarming worldwide increase in refugees. The total rose form 2.8 million in 1976 to 8.2 million in 1980, to 17.3 million in 1990. Africa's refugees rose from 1.2 million in 1976 to 5.6 million in 1990. Asia's increase over this period was much more rapid--from a mere 180,000 to 8 million. In the Americas the numbers more than trebled, from 770,000 to 2.7 million. Europe was the smallest increase, from 570,000 to 894,000. International law defines a refugee as someone outside of their own country, who has a well-founded fear of persecution because of their political or religious beliefs or ethnic origin, and who cannot turn to their own country for protection. Most refugees are genuine by this definition. The increase reflects, in part, fallout from the cold war. Ethiopia, Mozambique and Angola accounted for almost 1/2 of Africa's refugees; Afghanistan alone for 3/4 of Asia's total. They fled, for the most part, from 1 poor country into another, where they added to shortages of land and fuelwood, and intensified environmental pressure. Malawi, 1 of the poorest countries in the world, is sheltering perhaps as many as 750,000 refugees from the war in Mozambique. But among these refugees--especially among those who turned to the rich countries for asylum--were an increasing number of people who were not suffering political persecution. Driven out of their homes by the collapse of their environment or economic despair, and ready to take any means to get across borders, they are a new category: economic and environmental refugees. The most spectacular attempts hit the television screens: the Vietnamese boat people, ships festooned with Albanians. Behind the headlines there was a growing tide of asylum seekers. The numbers rose 10-fold in Germany from 1983 to 1990. In Switzerland they multiplied by 4 times. In Europe, as a whole, they grew from 71,000 in 1983 to an estimated 550,000 in 1990. In 1990 the numbers threatened to

  3. 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

  4. 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.

  5. 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.

  6. CHINA INCREASED PETROLEUM TAX

    Institute of Scientific and Technical Information of China (English)

    Mu Xueping

    2005-01-01

    @@ After half a year's gestation and adjustment, the State Administration of Taxation finally set new tax rate of petroleum resources. Notification issued by the Ministry of Finance and the State Administration of Taxation said the petroleum resources tax standard would be lifted nationwide, after the tax rate adjustment, tax on crude oil would be increased to RMB 14-30 yuan per ton and that on natural gas to RMB 7-15 yuan per thousand cubic meters. The new tax rate has been effective nationwide since July 1.

  7. Increasing Childhood Influenza Vaccination

    Science.gov (United States)

    Nowalk, Mary Patricia; Lin, Chyongchiou J.; Hannibal, Kristin; Reis, Evelyn C.; Gallik, Gregory; Moehling, Krissy K.; Huang, Hsin-Hui; Allred, Norma J.; Wolfson, David H.; Zimmerman, Richard K.

    2014-01-01

    Background Since the 2008 inception of universal childhood influenza vaccination, national rates have risen more dramatically among younger children than older children and reported rates across racial/ethnic groups are inconsistent. Interventions may be needed to address age and racial disparities to achieve the recommended childhood influenza vaccination target of 70%. Purpose To evaluate an intervention to increase childhood influenza vaccination across age and racial groups. Methods In 2011–2012, 20 primary care practices treating children were randomly assigned to Intervention and Control arms of a cluster randomized controlled trial to increase childhood influenza vaccination uptake using a toolkit and other strategies including early delivery of donated vaccine, in-service staff meetings, and publicity. Results The average vaccination differences from pre-intervention to the intervention year were significantly larger in the Intervention arm (n=10 practices) than the Control arm (n=10 practices), for children aged 2–8 years (10.2 percentage points (pct pts) Intervention vs 3.6 pct pts Control) and 9–18 years (11.1 pct pts Intervention vs 4.3 pct pts Control, p<0.05), for non-white children (16.7 pct pts Intervention vs 4.6 pct pts Control, p<0.001), and overall (9.9 pct pts Intervention vs 4.2 pct pts Control, p<0.01). In multi-level modeling that accounted for person- and practice-level variables and the interactions among age, race and intervention, the likelihood of vaccination increased with younger age group (6–23 months), white race, commercial insurance, the practice’s pre-intervention vaccination rate, and being in the Intervention arm. Estimates of the interaction terms indicated that the intervention increased the likelihood of vaccination for non-white children in all age groups and white children aged 9–18 years. Conclusions A multi-strategy intervention that includes a practice improvement toolkit can significantly improve influenza

  8. Increasing Inflationary Pressure

    Institute of Scientific and Technical Information of China (English)

    Guo Yan

    2008-01-01

    @@ China's CPI rose to 8.7 percent in February after hitting 7.1 percent in January,creating a 12-year high,the National Bureau of Statistics said.The figure exceeded market expectations,as the Bank of China,the country's secondlargest lender,had predicted a rise of only 8.3 percent.The Consumer Price Index (CPI)is the main gauge of inflation,andthe high CPI over the last two months has put pressure on the government to take action to curb the price increases,and added even more diffculty to the task of reining in this year's inflation rate.

  9. Core Noise - Increasing Importance

    Science.gov (United States)

    Hultgren, Lennart S.

    2011-01-01

    This presentation is a technical summary of and outlook for NASA-internal and NASA-sponsored external research on core (combustor and turbine) noise funded by the Fundamental Aeronautics Program Subsonic Fixed Wing (SFW) Project. Sections of the presentation cover: the SFW system-level noise metrics for the 2015, 2020, and 2025 timeframes; turbofan design trends and their aeroacoustic implications; the emerging importance of core noise and its relevance to the SFW Reduced-Perceived-Noise Technical Challenge; and the current research activities in the core-noise area, with additional details given about the development of a high-fidelity combustor-noise prediction capability as well as activities supporting the development of improved reduced-order, physics-based models for combustor-noise prediction. The need for benchmark data for validation of high-fidelity and modeling work and the value of a potential future diagnostic facility for testing of core-noise-reduction concepts are indicated. The NASA Fundamental Aeronautics Program has the principal objective of overcoming today's national challenges in air transportation. The SFW Reduced-Perceived-Noise Technical Challenge aims to develop concepts and technologies to dramatically reduce the perceived aircraft noise outside of airport boundaries. This reduction of aircraft noise is critical to enabling the anticipated large increase in future air traffic. Noise generated in the jet engine core, by sources such as the compressor, combustor, and turbine, can be a significant contribution to the overall noise signature at low-power conditions, typical of approach flight. At high engine power during takeoff, jet and fan noise have traditionally dominated over core noise. However, current design trends and expected technological advances in engine-cycle design as well as noise-reduction methods are likely to reduce non-core noise even at engine-power points higher than approach. In addition, future low-emission combustor

  10. Increasing Responsibility towards Environment

    Directory of Open Access Journals (Sweden)

    Mihaela Comanescu

    2009-11-01

    Full Text Available In the international climate of the early millennium, the need for reconciliation between economic and social development, on one hand, and the environment, on the other hand, is essential. Therefore, sustainable development must be promoted, because it integrates economic growth, improved quality of life, health, education, social development and environmental protection.Environmental issues are particularly complex as their causes are interdependent. This requires actions at all levels: local, national, regional as well as at the European Union level, each with its own role in increasing responsibility for the environmental protection.It is widely recognized that to obtain successful results an integrated approach has to be used to manage the environment, by adopting long-term strategies and action plans. It requires a detailed analysis of the links between different policies and responsibilities, including the links between different administrative levels.

  11. Increasing Responsibility towards Environment

    Directory of Open Access Journals (Sweden)

    Mihaela COMĂNESCU

    2010-05-01

    Full Text Available In the international climate of the early millennium, the need for reconciliation between economic and social development, on one hand, and the environment, on the other hand, is essential. Therefore, sustainable development must be promoted, because it integrates economic growth, improves quality of life, health, education, social development and environmental protection. Environmental issues are particularly complex as their causes are interdependent. This requires actions at all levels: local, national, regional as well as at the European Union level, each with its own role in increasing responsibility for the environmental protection. It is widely recognized that to obtain successful results an integrated approach has to be used to manage the environment, by adopting long-term strategies and action plans. It requires a detailed analysis of the links between different policies and responsibilities, including the links between different administrative levels.

  12. Elenoside increases intestinal motility

    Institute of Scientific and Technical Information of China (English)

    E Navarro; SJ Alonso; R Navarro; J Trujillo; E Jorge

    2006-01-01

    AIM: To study the effects of elenoside, an arylnaphthalene lignan from Justicia hyssopifolia, on gastrointestinal motility in vivo and in vitro in rats.METHODS: Routine in vivo experimental assessments were catharsis index, water percentage of boluses,intestinal transit, and codeine antagonism. The groups included were vehicle control (propylene glycol-ethanolplant oil-tween 80), elenoside (i.p. 25 and 50 mg/kg),cisapride (i.p. 10 mg/kg), and codeine phosphate (intragastric route, 50 mg/kg). In vitro approaches used isolated rat intestinal tissues (duodenum, jejunum, and ileum). The effects of elenoside at concentrations of 3.2× 10-4, 6.4 × 10-4 and 1.2 × 10-3 mol/L, and cisapride at 10-6 mol/L were investigated.RESULTS: Elenoside in vivo produced an increase in the catharsis index and water percentage of boluses and in the percentage of distance traveled by a suspension of activated charcoal. Codeine phosphate antagonized the effect of 25 mg/kg of elenoside. In vitro, elenoside in duodenum, jejunum and ileum produced an initial decrease in the contraction force followed by an increase.Elenoside resulted in decreased intestinal frequency in duodenum, jejunum, and ileum. The in vitro and in vivo effects of elenoside were similar to those produced by cisapride.CONCLUSION: Elenoside is a lignan with an action similar to that of purgative and prokinetics drugs.Elenoside, could be an alternative to cisapride in treatment of gastrointestinal diseases as well as a preventive therapy for the undesirable gastrointestinal effects produced by opioids used for mild to moderate pain.

  13. Increasing Possibilities of Nanosuspension

    Directory of Open Access Journals (Sweden)

    Kumar Bishwajit Sutradhar

    2013-01-01

    Full Text Available Nowadays, a very large proportion of new drug candidates emerging from drug discovery programmes are water insoluble and thus poorly bioavailable. To avoid this problem, nanotechnology for drug delivery has gained much interest as a way to improve the solubility problems. Nano refers to particles size range of 1–1000 nm. The reduction of drug particles into the submicron range leads to a significant increase in the dissolution rate and therefore enhances bioavailability. Nanosuspensions are part of nanotechnology. This interacts with the body at subcellular (i.e., molecular scales with a high degree of specificity and can be potentially translated into targeted cellular and tissue-specific clinical applications designed to achieve maximal therapeutic efficacy with minimal side effects. Production of drugs as nanosuspensions can be developed for drug delivery systems as an oral formulation and nonoral administration. Here, this review describes the methods of pharmaceutical nanosuspension production including advantages and disadvantages, potential benefits, characterization tests, and pharmaceutical applications in drug delivery.

  14. Increasing orUnderselling ?

    Institute of Scientific and Technical Information of China (English)

    Guo Yan

    2011-01-01

    The downgrade of sovereignty credit rating of the United States causes new concerns on US treasury bonds.According to the report issued recently by Treasury Ministry of United States,China as the largest oversea holding country of US treasury bonds continues to buy US treasury bonds,with an increase of 5.7 billion US dollars in June,marking the third month in line.Till now,China has US treasury bonds up to a new record of 1,165.5 billion US dollars,which amounts to 26% of the oversea holding US treasury bonds,based on market estimation,followed by Japan (20%),UK (8%),Brazil (5%)and Russia (3%).However,in sharp contrast to China,other countries are underselling us treasury bonds,particularly Russia.Data shows that since October 2010,Russia has been selling US treasury bonds for eight months in line,up to 38% of their holdings.Now Russia only holds 111 billion US dollars of US treasury bond.Why the countries take totally different attitudes towards to US treasury bonds? Tne reporter interviewed the experts from China and Russia for more details.

  15. 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.

  16. Increasing instruction time in school does increase learning

    DEFF Research Database (Denmark)

    Humlum, Maria; Nandrup, Anne Brink; Andersen, Simon Calmar

    2016-01-01

    Increasing instruction time in school is a central element in the attempts of many governments to improve student learning, but prior research—mainly based on observational data—disputes the effect of this approach and points out the potential negative effects on student behavior. Based on a large......-scale, cluster-randomized trial, we find that increasing instruction time increases student learning and that a general increase in instruction time is at least as efficient as an expert-developed, detailed teaching program that increases instruction with the same amount of time. These findings support the value...

  17. Strong increase of solar panels

    International Nuclear Information System (INIS)

    The number of installed solar panels in 2011 has increased again. 40 megawatt of new panels have been installed. This increase is twice as high as the year before. The production of solar power increased to 90 million kWh in 2011 as a result of this expansion. However, the share of solar power in total energy use is still very limited.

  18. Recombinant Rhipicephalus appendiculatus gut (Ra86 and salivary gland cement (Trp64 proteins as candidate antigens for inclusion in tick vaccines: protective effects of Ra86 on infestation with adult R. appendiculatus

    Directory of Open Access Journals (Sweden)

    Saimo M

    2011-11-01

    Full Text Available Margaret Saimo1,2,*, David O Odongo3,4,*, Stephen Mwaura3, Just M Vlak1, Anthony J Musoke5, George W Lubega2, Richard P Bishop3, Monique M van Oers11Laboratory of Virology, Wageningen University, Wageningen, The Netherlands; 2School of Veterinary Medicine, Makerere University, Kampala, Uganda; 3International Livestock Research Institute, Nairobi, Kenya; 4School of Biological Sciences, University of Nairobi, Nairobi, Kenya; 5Onderstepoort Veterinary Institute, Onderstepoort, Pretoria, South Africa *These two authors made an equal contribution to this workAbstract: Rhipicephalus appendiculatus gut protein Ra86 (variants Ra85A and Ra92A and the salivary gland cement protein (Trp64 were expressed in the baculovirus-insect cell system. The recombinant gut proteins expressed as soluble proteins and the recombinant cement protein, as insoluble inclusion bodies, were used to immunize rabbits, which were then challenged with larval, nymphal, and adult stages of R. appendiculatus ticks. High tick mortality (23.3% occurred on adult ticks that fed on rabbits vaccinated with the gut proteins, compared with 1.9% mortality in ticks that fed on unvaccinated naïve control rabbits. The mean weight of engorged female ticks was significantly reduced by 31.5% in rabbits vaccinated with the Ra86 recombinant protein compared with controls, as was egg production. Marked effects on these parameters were also observed in adult ticks as a result from vaccination using Trp64, but these were not statistically significant. For both antigens, there was no demonstrable effect on larval or nymphal ticks. This study demonstrates for the first time the protective efficacy of a homolog of Boophilus microplus Bm86 in reducing tick infestation by the adult stage of the three-host tick R. appendiculatus. The results demonstrate the potential of Ra86 for vaccine development against this tick and for the control of East Coast fever.Keywords: baculovirus, Ra85A, Ra92A, Boophilus

  19. Increasing tobacco taxes : A cheap tool to increase public health

    NARCIS (Netherlands)

    van Baal, Pieter H. M.; Brouwer, Werner B. F.; Hoogenveen, Rudolf T.; Feenstra, Talitha L.

    2007-01-01

    Introduction: Several studies have estimated health effects resulting from tobacco tax increases. However, studies on the cost effectiveness of tobacco taxes are scarce. The aim of this study was to estimate the cost effectiveness of tobacco tax increases from a health care perspective, explicitly c

  20. Genetic parameters and investigation of genotype × environment interactions in Nellore × Hereford crossbred for resistance to cattle ticks in different regions of Brazil.

    Science.gov (United States)

    Ayres, D R; Pereira, R J; Boligon, A A; Baldi, F; Roso, V M; Albuquerque, L G

    2015-02-01

    Data from 6,156 Nellore × Hereford crossbred cattle, distributed in 18 herds located in the Brazilian states of Mato Grosso do Sul (MS), São Paulo (SP), Paraná (PR) and Rio Grande do Sul (RS), were analysed in order to investigate genetic variation for resistance to the cattle tick through the estimation of variance components and genetic parameters for counting ticks (Rhipicephalus (Boophilus) microplus) in natural infestation, and also a possible genotype × environment interaction. The tick count data (CC) were transformed to log10(CC + 1) and grouped into two regions, defined by cluster analysis and analysed using the method of restricted maximum likelihood. The statistical model included the additive genetic effect as random and fixed effects of the contemporary group (CG) and genetic group (GG) as classificatory and the age of the animal at the time of counting (linear effect) and individual heterozygosity (linear effect, ranging from 0 to 1) as covariates. In the studied regions, the effect of heterosis found was inversely proportional; in other words, the count of ticks decreased with the increase of heterozygosity. The observed heritability estimation for resistance to tick infestation were 0.12 ± 0.04 and 0.11 ± 0.04 for groups A (RS and south PR) and B (MS, SP and north PR), respectively. The results of this study suggest that selection for animals resistant to ticks would be possible using the tick count to estimate the genetic value of animals, but with a slow genetic progress. The genetic correlation for tick count between the two groups (A and B) was 0.84 ± 0.27 and genotype × environment interaction for this trait was not observed in the studied population. PMID:25108748

  1. THE INCIDENCE OF PARASITIC DISEASES IN LIVESTOCK IN BALI

    Directory of Open Access Journals (Sweden)

    N. A. Suratma

    2012-09-01

    Full Text Available The population of livestock in Bali has continuously increased from year to year. However, some problems are encountered with parasitic infections in livestock. Parasitic infections may be caused by worms, protozoa or ectoparasites. In cattle, the most common infections are those caused by Oesophagostomum sp, Ostertagia sp, Haemonchus sp, Mecistocirrus sp, and Cooperia sp which is the most dominant. Neoascaris vitulorum was reported to be as high as 29.1% in calves. Fascioliasis in cattle was found highly prevalent, between 34.9 to 56.7% and was caused by Fasciola gigantica. Also Paramphistomum infection was reported to be highly prevalent (50.1%. In addition, Boophilus microplus was recorded as high as 36.9%. In goat and sheep, the incidence of Haemonchus contortus was 27.7% and 53.6% respectively. Infestation of Paramphistomum sp in goat was 9.27%. Concerning ectoparasites, Sarcoptes scabiei was reported to be the cause of death of 67% of young goats and up to 11% of older gats in Br. Penginuman, Gilimanuk Negara. Parasitic infections in pigs were caused by Cysticercus tenuicollis (11% and Ascaris suum (24.2% and 21.1% showed Metastrongylus apri and also Sarcoptes scabiei was reported to be the cause of skin disease in pigs. In poultry, parasitic infection were caused by Raillietina (96%, Heterakis gallinae (66.7%, Capillaria sp (6.6%, Ascardia galli (56.7%, Oxyspirura mansoni (50%, Acuaria spiralis (13.3% and Syngamus trachea (3.3%. Multiple infections are common.

  2. Characterization of ferritin 2 for the control of tick infestations.

    Science.gov (United States)

    Hajdusek, Ondrej; Almazán, Consuelo; Loosova, Gabriela; Villar, Margarita; Canales, Mario; Grubhoffer, Libor; Kopacek, Petr; de la Fuente, José

    2010-04-01

    Ixodes ricinus is one the most abundant tick species in Europe and these ticks transmit pathogens causing human and animal diseases. The cattle ticks, Rhipicephalus (Boophilus) spp., affect cattle production in tropical and subtropical regions of the world. Development of vaccines directed against tick proteins may reduce tick infestations and the transmission of tick-borne pathogens. However, a limiting step in tick vaccine development has been the identification of tick protective antigens. Herein, the tick iron metabolism pathway was targeted in an effort to identify new tick protective antigens. Recombinant I. ricinus (IrFER2) and Rhipicephalus microplus (RmFER2) ferritin 2 proteins were expressed in Escherichia coli and used to immunize rabbits and cattle, respectively. Vaccination with IrFER2 reduced I. ricinus tick numbers, weight and fertility in rabbits with an overall vaccine efficacy (E) of 98%. Control of cattle tick, R. microplus and Rhipicephalus annulatus infestations was obtained in vaccinated cattle with overall E of 64% and 72%, respectively. Notably, the efficacy of the RmFER2 vaccine was similar to that obtained with Bm86 against R. microplus. These collective results demonstrated the feasibility of using ferritin 2 to develop vaccines for the control of tick infestations. PMID:20171306

  3. Assessing and Increasing Physical Activity

    Science.gov (United States)

    Van Camp, Carole M.; Hayes, Lynda B.

    2012-01-01

    Increasing physical activity is a crucial component of any comprehensive approach to combat the growing obesity epidemic. This review summarizes recent behavioral research on the measurement of physical activity and interventions aimed at increasing physical activity and provides directions for future research.

  4. RESTAURANT NO. 2: PRICE INCREASES

    CERN Multimedia

    2003-01-01

    'DSR', the concession holder of Restaurant no. 2 (bldg. 504 - Meyrin site), has submitted to the Restaurant Supervisory Committee a request to increase certain prices. After close examination, the Committee has established that the proposed increases are compatible with the relevant price indexing mechanisms and other contractual conditions. The new prices will apply as from Monday, June 30, 2003.

  5. RESTAURANT NO. 3: PRICE INCREASES

    CERN Multimedia

    2003-01-01

    'AVENANCE', the concession holder of Restaurant no. 3 (bldg. 866 - Prévessin site), has submitted to the Restaurant Supervisory Committee a request to increase its prices. After close examination, the Committee has established that the proposed increases are compatible with the relevant price indexing mechanisms and other contractual conditions. The new prices will apply as from Monday, June 2, 2003.

  6. Strategies to Increase Physical Activity

    OpenAIRE

    Tuso, Phillip

    2015-01-01

    One key intervention to prevent preventable diseases and to make health care more affordable is to increase the percentage of Americans who are physically active. No single intervention will increase activity rates, but a group of interventions working together in synergy may be the stimulus needed to get Americans moving.

  7. Demand for Phenol Increases Steadily

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Dramatic growth in output By the end of 2006 China's capacity to produce phenol had reached more than 600 thousand t/a. The total output was 523 thousand tons in 2006,an increase of 18.1% over 2005.

  8. Demand for SBR Increased Steadily

    Institute of Scientific and Technical Information of China (English)

    Gao Yiwen

    2007-01-01

    @@ 1 Rapid consumption growth Consumption of styrene-butadiene rubber (SBR) in China was 747 thousand tons in 2006, an increase of 21% over 2005, with faster growth than the average rubber consumption growth.

  9. Increasing Learning from TV News.

    Science.gov (United States)

    Perloff, Richard M.; And Others

    1982-01-01

    Describes an experiment that manipulated two variables, repetition and pausing for viewer "digestion" of information in a news telecast. Concludes that the use of repetition increased viewers' retention of information, but that pauses did not. (FL)

  10. RESTAURANT NO. 3 : PRICE INCREASES

    CERN Multimedia

    Restaurant Supervisory Committee

    2002-01-01

    'AVENANCE', the concession holder of Restaurant no. 3 (bldg. 866 - Prévessin site), has submitted to the Restaurant Supervisory Committee a request to increase its prices. After close examination, the Committee has established that the proposed increases are compatible with the relevant price indexing mechanisms and other contractual conditions. The new prices will apply as from Monday, June 3, 2002. Restaurant Supervisory Committee, tel. 77551

  11. INCREASING RETURN TO SMART CITIES

    OpenAIRE

    Lööf, Hans; Nabavi, Pardis

    2012-01-01

    Increased urbanization, global warming and sustainable growth belong to the major contemporary policy challenges. Today cities are home to more than 50% of the world population, the largest 600 urban centers generate about 60% of global GDP, and the agglomerated areas are responsible for 75% of world carbon emissions. The UN estimates that 70% of the world's growing population will live in cities by 2050. At the same time the world population is expected to increase from 7 billion people to 9...

  12. Research Evaluation to Increase Impact

    OpenAIRE

    Templeton, Deborah J.

    2003-01-01

    Research evaluation, undertaken throughout the life of the research activity, is an important tool for research managers. When correctly implemented, research evaluation can help to increase the success of existing and future research projects and programs, thereby increasing the social, economic and/or environmental impact of the research. The relationship between the life-cycle of the research project and the type of evaluation determines the appropriate type of evaluation to be undertaken....

  13. Meclofenamate increases ventilation in lambs.

    Science.gov (United States)

    Guerra, F A; Savich, R D; Clyman, R I; Kitterman, J A

    1989-01-01

    To investigate the effects of the prostaglandin synthetase inhibitor, meclofenamate, on postnatal ventilation, we studied 11 unanaesthetised, spontaneously-breathing lambs at an average age of 7.9 +/- 1.1 days (SEM; range 5-14 days) and an average weight of 4.9 +/- 0.5 kg (range 3.0-7.0 kg). After a 30-min control period we infused 4.23 mg/kg meclofenamate over 10 min and then gave 0.23 mg/h per kg for the remainder of the 4 h. Ventilation increased progressively from a control value of 515 +/- 72 ml/min per kg to a maximum of 753 +/- 100 ml/min per kg after 3h of infusion (P less than 0.05) due to an increased breathing rate; the effects were similar during both high- and low-voltage electrocortical activity. There were no significant changes in tidal volume, heart rate, blood pressure, arterial pH or PaCO2, the increased ventilation resulted from either an increase in dead space ventilation or an increase in CO2 production. This study indicates that meclofenamate causes an increase in ventilation in lambs but no changes in pH of PaCO2. The mechanism and site of action remain to be defined. PMID:2507622

  14. Increasing work-time influence

    DEFF Research Database (Denmark)

    Nabe-Nielsen, Kirsten; Garde, Anne Helene; Aust, Birgit;

    2012-01-01

    This quasi-experimental study investigated how an intervention aiming at increasing eldercare workers' influence on their working hours affected the flexibility, variability, regularity and predictability of the working hours. We used baseline (n = 296) and follow-up (n = 274) questionnaire data......-operation with colleagues. In subgroup B and C, the participants ended up discussing the potential consequences of more work-time influence without actually implementing any changes. PRACTITIONER SUMMARY: Employee work-time influence may buffer the adverse effects of shift work. However, our intervention study suggested...... that while increasing the individual flexibility, increasing work-time influence may also result in decreased regularity of the working hours and less continuity in the care of clients and co-operation with colleagues....

  15. Increased burnup of fuel elements

    International Nuclear Information System (INIS)

    The specialists' group for fuel elements of the Kerntechnische Gesellschaft e.V. held a meeting on ''Increased Burnup of Fuel Elements'' on 9th and 10th of November 1982 at the GKSS Research Center Geesthacht. Most papers dealt with the problems of burnup increase of fuel elements for light water reactors with respect to fuel manufacturing, power plant operation and reprocessing. Review papers were given on the burnup limits for high temperature gas cooled reactors and sodium fast breeder reactors. The meeting ended with a presentation of the technical equipment of the hot laboratory of the GKSS and the programs which are in progress there. (orig.)

  16. Increased Spreading Activation in Depression

    Science.gov (United States)

    Foster, Paul S.; Yung, Raegan C.; Branch, Kaylei K.; Stringer, Kristi; Ferguson, Brad J.; Sullivan, William; Drago, Valeria

    2011-01-01

    The dopaminergic system is implicated in depressive disorders and research has also shown that dopamine constricts lexical/semantic networks by reducing spreading activation. Hence, depression, which is linked to reductions of dopamine, may be associated with increased spreading activation. However, research has generally found no effects of…

  17. Electromigration early resistance increase measurements

    NARCIS (Netherlands)

    Niehof, J.; Flinn, P.A.; Maloney, T.J.

    1993-01-01

    An early resistance change measurement set-up, using an AC bridge technique, has been developed, and measurements have been performed. Large sample-to-sample variations occur. The characteristic time for the resistance change curve is shorter for resistance increase (under current stress) than for r

  18. How to increase living donation.

    Science.gov (United States)

    Davis, Connie L

    2011-04-01

    Living donation is the key to increasing access to successful solid organ transplantation worldwide. However, the means to expanding the number of living donors on a global scale are not known. Although there have been many suggestions for the best approach, cultural issues may limit the effectiveness of some strategies. Only a few ideas have been studied, and one in particular- outright payment to donors - may raise ethical issues that are difficult to surmount and might negatively alter altruistic behavior. With respect to the present environment, this article will describe some of the approaches that are being discussed to increase the number of living donors, with a particular focus on kidney transplantation. PMID:21210867

  19. Increasing Accuracy in Environmental Measurements

    Science.gov (United States)

    Jacksier, Tracey; Fernandes, Adelino; Matthew, Matt; Lehmann, Horst

    2016-04-01

    Human activity is increasing the concentrations of green house gases (GHG) in the atmosphere which results in temperature increases. High precision is a key requirement of atmospheric measurements to study the global carbon cycle and its effect on climate change. Natural air containing stable isotopes are used in GHG monitoring to calibrate analytical equipment. This presentation will examine the natural air and isotopic mixture preparation process, for both molecular and isotopic concentrations, for a range of components and delta values. The role of precisely characterized source material will be presented. Analysis of individual cylinders within multiple batches will be presented to demonstrate the ability to dynamically fill multiple cylinders containing identical compositions without isotopic fractionation. Additional emphasis will focus on the ability to adjust isotope ratios to more closely bracket sample types without the reliance on combusting naturally occurring materials, thereby improving analytical accuracy.

  20. Price Increases from Online Privacy

    OpenAIRE

    Ward, Michael R; Chen, Yu-Ching

    2001-01-01

    Consumers value keeping some information about them private from potential marketers. E-commerce dramatically increases the potential for marketers to accumulate otherwise private information about potential customers. Online marketers claim that this information enables them to better market their products. Policy makers are currently drafting rules to regulate the way in which these marketers can collect, store, and share this information. However, there is little evidence yet either of con...

  1. Production Increased with Price Rise

    Institute of Scientific and Technical Information of China (English)

    Feng Shiliang

    2007-01-01

    @@ In April 2007, China's petroleum and chemical industry remained up trend in production. Among the 65 types of petrochemical products that have been tracked by CPCIA (China Petroleum and Chemical Industry Association), the output of 61 types increased compared with April 2006,accounting for 93.8% of the total, and the output of 15 types, in particular, grew by over 20%, accounting for 23.1%.

  2. NSF and NASA budgets increased

    Science.gov (United States)

    Bell, Peter M.

    Research budgets of several of the federal government agencies were increased significantly over the Reagan administration's requests in the House of Representative's appropriations bill H.R. 4034. These budgets had been removed from the Reagan administration's omnibus reconciliation bill, and thus there were worries expressed that certain research funding could be in jeopardy. The rationale was that because the requests were voted on individually on the floor of the House, many sections of the budgets would be subjected to extra scrutiny, which would lead to more cuts.The National Science Foundation (NSF) budget request had been cut and reordered by the Office of Management and Budget (OMB) by making sharp reductions in programs of the social sciences and in programs of science and engineering education. There were fears that these programs would be reinstated to the original request level, at the expense of the budgets of other research activities. These fears materialized, but only momentarily. Efforts to cut the research activities by the House Appropriations Committee were soundly defeated. The budget was supported, with additional increases to provide for the education programs, by a high margin, which included most Republican and Democratic members of the House of Representatives. The overall NSF budget, as passed, has a total appropriation of $1103.5 million, compared with the Administration's request of $1033.5 million (the Fiscal Year 1981 appropriation for the NSF was $1022.4 million). The House approved budget included increases of $44.9 million in research and $25.1 million in science and engineering education. Included in the research budget increase were recommendations by the House Appropriations Committee for support of the social sciences and for the international affairs programs. Also included in the recommendations was support of interdisciplinary research programs that cut across the directorates of the NSF.

  3. Production Increased with Higher Prices

    Institute of Scientific and Technical Information of China (English)

    Feng shiling

    2007-01-01

    @@ In the first quarter of 2007, China's petroleum and chemical industry remained up trend in production.Among the 66 types of petrochemical products that have been tracked by CPCIA (China Petroleum and Chemical Industry Association), the output of 58, types increased compared with the same period of 2006, accounting for 87.9% of the total, and the output of 19 types, in particular, grew by over20%, accounting for 28.8%.

  4. How trade unions increase welfare

    OpenAIRE

    Donado, Alejandro; Klaus WALDE

    2010-01-01

    Historically, worker movements have played a crucial role in making workplaces safer. Firms traditionally oppose better health standards. According to our interpretation, workplace safety is costly for firms but increases the average health of workers and thereby the aggregate labour supply. A laissez-faire approach in which firms set safety standards is suboptimal as workers are not fully informed of health risks associated with jobs. Safety standards set by better-informed trade unions are ...

  5. High Heels Increase Women's Attractiveness.

    Science.gov (United States)

    Guéguen, Nicolas

    2015-11-01

    Research has found that the appearance of women's apparel helps increase their attractiveness as rated by men and that men care more about physical features in potential opposite-sex mates. However, the effect of sartorial appearance has received little interest from scientists. In a series of studies, the length of women's shoe heels was examined. A woman confederate wearing black shoes with 0, 5, or 9 cm heels asked men for help in various circumstances. In Study 1, she asked men to respond to a short survey on gender equality. In Study 2, the confederate asked men and women to participate in a survey on local food habit consumption. In Study 3, men and women in the street were observed while walking in back of the female confederate who dropped a glove apparently unaware of her loss. It was found that men's helping behavior increased as soon as heel length increased. However, heel length had no effect on women's helping behavior. It was also found that men spontaneously approached women more quickly when they wore high-heeled shoes (Study 4). Change in gait, foot-size judgment, and misattribution of sexiness and sexual intent were used as possible explanations. PMID:25408499

  6. Increase Productivity Through Knowledge Management

    Science.gov (United States)

    Gavrikova, N. A.; Dolgih, I. N.; Dyrina, E. N.

    2016-04-01

    Increase in competition level requires companies to improve the efficiency of work force use characterized by labor productivity. Professional knowledge of staff and its experience play the key role in it. The results of Extrusion Line operator’s working time analysis are performed in this article. The analysis revealed that the reasons of working time ineffective use connected with inadequate information exchange and knowledge management in the company. Authors suggest the way to solve this problem: the main sources of knowledge in engineering enterprise have been defined, the conditions of success and the stages of knowledge management control have been stated.

  7. Do trade missions increase trade?

    OpenAIRE

    Head, Keith; Ries, John

    2010-01-01

    In an effort to stimulate trade, Canada has conducted regular trade missions starting in 1994, often led by the Prime Minister. According to the Canadian government, these missions generated tens of billions of dollars in new business deals. This paper uses bilateral trade data to assess this claim. We find that Canada exports and imports above-normal amounts to the countries to which it sent trade missions. However, the missions do not seem to have caused an increase in trade. In the preferr...

  8. Increasing Security in Cloud Environment

    OpenAIRE

    Naik, Priyanka; Sanyal, Sugata

    2013-01-01

    The concept of cloud computing was introduced to meet the increase in demand for new application for a project, and to provide a large storage facility whenever or wherever a user needs it. The cloud system facility helped many industries as well as individual users to get authentic software at a very low cost. But with this new system comes the major concern of security, as the connection to the cloud is through the web and the data and application availability need to be handled for each cl...

  9. [Ozone decline and UV increase].

    Science.gov (United States)

    Winkler, P; Trepte, S

    2004-02-01

    The following results have been obtained from long-term observations on the ozone layer and UV at the Meteorological Observatory Hohenpeigenberg:The seasonally varying decline of the ozone layer determines the maximum exposure to UV. Since ozone decline shows the highest rates in the spring months the UV exposure has most strongly increased in this time of the year. This is especially important because in spring the human skin is not adapted to UV exposure. Weather changes from day to day can induce rapid ozone reductions in spring about -30% which in turn is followed by an increase in UV of about 40%. Clouds, especially the transparent cirrus clouds (high clouds consisting of ice particles) have increased in frequency during spring and fall while a decrease is observed in summer. This change in cloudiness reduces the daily UV dose in spring and fall while it is enhanced in summer. With increasing height above sea level UV rises by roughly 10% per 1000 m (rule of thumb). Snow reflects the UV-radiation by up to 80% enhancing the UV-doses at relevant conditions. Strong volcano eruptions destroy ozone in the stratosphere additionally during 1-2 years after the eruption. Therafter the ozone layer recovers. In April 1993, after the eruption of Mt. Pinatubo (1991), the UV burden was still 40% higher than average. Miniholes and streamers can appear unexpected on a short-time scale and cross over Central Europe within 1-2 days, thus enhancing UV irradiation. The human skin reacts to UV exposure depending on the type of skin. The campaign "Sonne(n) mit Verstand" of the Bavarian Ministries for Environment, for Health and for Education informs about the danger of UV radiation (see www.sonne-mit-ver-stand.de). The German Weather Service informs the public on present developments of the ozone layer and relevant topics byits ozone bulletin, which is also available via internet under (www.dwd.de/deFundE/Observator/MOHp/hp2/ozon/bulletin.htm). PMID:14770335

  10. Increasing situational awareness using smartphones

    Science.gov (United States)

    Boddhu, Sanjay K.; Williams, Robert L.; Wasser, Edward; Kode, Niranjan

    2012-06-01

    In recent years, the United States Armed Services and various law enforcement agencies have shown increasing interest in evaluating the feasibility of using smartphones and hand-held devices as part of the standard gear for its personnel, who are actively engaged on battlefield or in crime-prone areas. The primary motive driving analysis efforts to employ smartphone-based technologies is the prospect of the increased "Situational Awareness" achievable thru a digitally connected network of armed personnel. Personnel would be equipped with customized smart applications that use the device's sensors (GPS, camera, compass, etc...) to sense the hostile environments as well as enabling them to perform collaborative tasks to effectively complete a given mission. In this vein, as part of the Summer At The Edge (SATE) program, a group of student interns under the guidance of mentors from Qbase and AFRL, have employed smartphones and built three smart applications to tackle three real-world scenarios: PinPoint, IStream, and Cooperative GPS. This paper provides implementation details for these prototype applications, along with the supporting visualization and sensor cloud platforms and discusses results obtained from field testing of the same. Further, the paper concludes by providing the implications of the present work and insights into future work.

  11. [Patients' increasing role in healthcare].

    Science.gov (United States)

    Colombo, Cinzia

    2016-03-01

    Since the late '90s citizens have been increasingly involved in healthcare, thanks to a shift in access to healthcare information, greater patients' and citizens' awareness about their rights and needs, and a change in physicians' attitudes and behavior. At the same time, to ensure the sustainability of the national health services, patients' needs are increasingly being examined in relation to the services and interventions needed, and to foster informed demand by patients and citizens, and appropriate prescriptions by physicians. Nowadays, patients already have a section in an authoritative medical journal. Working with clinicians, they set research priorities and the outcomes to be studied. Especially in UK and USA, they are invited to participate in the design and development of trials and in deciding which trials should be funded. The situation varies widely in different countries, though involving citizens in healthcare decisions is a common mantra. Even when they consult a clinician, the patients' role has evolved. People ask for information more often and want an active part in decisions about their health. Physicians start to pay more attention to the person and the social context, feelings and emotions, and person-centered care has become a reference in the doctor-patient relationship. This article offers an overview of the changing roles of patients and citizens in healthcare.

  12. Thunderstorms Increase Mercury Wet Deposition.

    Science.gov (United States)

    Holmes, Christopher D; Krishnamurthy, Nishanth P; Caffrey, Jane M; Landing, William M; Edgerton, Eric S; Knapp, Kenneth R; Nair, Udaysankar S

    2016-09-01

    Mercury (Hg) wet deposition, transfer from the atmosphere to Earth's surface by precipitation, in the United States is highest in locations and seasons with frequent deep convective thunderstorms, but it has never been demonstrated whether the connection is causal or simple coincidence. We use rainwater samples from over 800 individual precipitation events to show that thunderstorms increase Hg concentrations by 50% relative to weak convective or stratiform events of equal precipitation depth. Radar and satellite observations reveal that strong convection reaching the upper troposphere (where high atmospheric concentrations of soluble, oxidized mercury species (Hg(II)) are known to reside) produces the highest Hg concentrations in rain. As a result, precipitation meteorology, especially thunderstorm frequency and total rainfall, explains differences in Hg deposition between study sites located in the eastern United States. Assessing the fate of atmospheric mercury thus requires bridging the scales of global transport and convective precipitation. PMID:27464305

  13. Increasing of Reliability of Converter

    Directory of Open Access Journals (Sweden)

    Trebuňa, F.

    2006-01-01

    Full Text Available The innovative activities in steel production invoke exploitation of new machines with the higher production capacity and productivity of labor. The paper deals with deformation and stress analysis of carrying parts of converter pedestal on the base of which the proposals and supporting measures were made that had the aim to increase reliability of the converter during steel production. This was achieved by lifespan prolongation of anchor and connecting bolts of converter pedestal, by change of stiffness of connected elements as well as by correction of nuts of bolted connections. The realization of structural changes decreased loading amplitudes and consequently the vibrations of pedestal. Solution was verified by numerical and experimental procedures of mechanics.

  14. Propofol directly increases tau phosphorylation.

    Directory of Open Access Journals (Sweden)

    Robert A Whittington

    Full Text Available In Alzheimer's disease (AD and other tauopathies, the microtubule-associated protein tau can undergo aberrant hyperphosphorylation potentially leading to the development of neurofibrillary pathology. Anesthetics have been previously shown to induce tau hyperphosphorylation through a mechanism involving hypothermia-induced inhibition of protein phosphatase 2A (PP2A activity. However, the effects of propofol, a common clinically used intravenous anesthetic, on tau phosphorylation under normothermic conditions are unknown. We investigated the effects of a general anesthetic dose of propofol on levels of phosphorylated tau in the mouse hippocampus and cortex under normothermic conditions. Thirty min following the administration of propofol 250 mg/kg i.p., significant increases in tau phosphorylation were observed at the AT8, CP13, and PHF-1 phosphoepitopes in the hippocampus, as well as at AT8, PHF-1, MC6, pS262, and pS422 epitopes in the cortex. However, we did not detect somatodendritic relocalization of tau. In both brain regions, tau hyperphosphorylation persisted at the AT8 epitope 2 h following propofol, although the sedative effects of the drug were no longer evident at this time point. By 6 h following propofol, levels of phosphorylated tau at AT8 returned to control levels. An initial decrease in the activity and expression of PP2A were observed, suggesting that PP2A inhibition is at least partly responsible for the hyperphosphorylation of tau at multiple sites following 30 min of propofol exposure. We also examined tau phosphorylation in SH-SY5Y cells transfected to overexpress human tau. A 1 h exposure to a clinically relevant concentration of propofol in vitro was also associated with tau hyperphosphorylation. These findings suggest that propofol increases tau phosphorylation both in vivo and in vitro under normothermic conditions, and further studies are warranted to determine the impact of this anesthetic on the acceleration of

  15. Slow motion increases perceived intent.

    Science.gov (United States)

    Caruso, Eugene M; Burns, Zachary C; Converse, Benjamin A

    2016-08-16

    To determine the appropriate punishment for a harmful action, people must often make inferences about the transgressor's intent. In courtrooms and popular media, such inferences increasingly rely on video evidence, which is often played in "slow motion." Four experiments (n = 1,610) involving real surveillance footage from a murder or broadcast replays of violent contact in professional football demonstrate that viewing an action in slow motion, compared with regular speed, can cause viewers to perceive an action as more intentional. This slow motion intentionality bias occurred, in part, because slow motion video caused participants to feel like the actor had more time to act, even when they knew how much clock time had actually elapsed. Four additional experiments (n = 2,737) reveal that allowing viewers to see both regular speed and slow motion replay mitigates the bias, but does not eliminate it. We conclude that an empirical understanding of the effect of slow motion on mental state attribution should inform the life-or-death decisions that are currently based on tacit assumptions about the objectivity of human perception. PMID:27482091

  16. Vocal attractiveness increases by averaging.

    Science.gov (United States)

    Bruckert, Laetitia; Bestelmeyer, Patricia; Latinus, Marianne; Rouger, Julien; Charest, Ian; Rousselet, Guillaume A; Kawahara, Hideki; Belin, Pascal

    2010-01-26

    Vocal attractiveness has a profound influence on listeners-a bias known as the "what sounds beautiful is good" vocal attractiveness stereotype [1]-with tangible impact on a voice owner's success at mating, job applications, and/or elections. The prevailing view holds that attractive voices are those that signal desirable attributes in a potential mate [2-4]-e.g., lower pitch in male voices. However, this account does not explain our preferences in more general social contexts in which voices of both genders are evaluated. Here we show that averaging voices via auditory morphing [5] results in more attractive voices, irrespective of the speaker's or listener's gender. Moreover, we show that this phenomenon is largely explained by two independent by-products of averaging: a smoother voice texture (reduced aperiodicities) and a greater similarity in pitch and timbre with the average of all voices (reduced "distance to mean"). These results provide the first evidence for a phenomenon of vocal attractiveness increases by averaging, analogous to a well-established effect of facial averaging [6, 7]. They highlight prototype-based coding [8] as a central feature of voice perception, emphasizing the similarity in the mechanisms of face and voice perception.

  17. Vocal attractiveness increases by averaging.

    Science.gov (United States)

    Bruckert, Laetitia; Bestelmeyer, Patricia; Latinus, Marianne; Rouger, Julien; Charest, Ian; Rousselet, Guillaume A; Kawahara, Hideki; Belin, Pascal

    2010-01-26

    Vocal attractiveness has a profound influence on listeners-a bias known as the "what sounds beautiful is good" vocal attractiveness stereotype [1]-with tangible impact on a voice owner's success at mating, job applications, and/or elections. The prevailing view holds that attractive voices are those that signal desirable attributes in a potential mate [2-4]-e.g., lower pitch in male voices. However, this account does not explain our preferences in more general social contexts in which voices of both genders are evaluated. Here we show that averaging voices via auditory morphing [5] results in more attractive voices, irrespective of the speaker's or listener's gender. Moreover, we show that this phenomenon is largely explained by two independent by-products of averaging: a smoother voice texture (reduced aperiodicities) and a greater similarity in pitch and timbre with the average of all voices (reduced "distance to mean"). These results provide the first evidence for a phenomenon of vocal attractiveness increases by averaging, analogous to a well-established effect of facial averaging [6, 7]. They highlight prototype-based coding [8] as a central feature of voice perception, emphasizing the similarity in the mechanisms of face and voice perception. PMID:20129047

  18. The increasing burden of depression

    Directory of Open Access Journals (Sweden)

    Lépine J-P

    2011-05-01

    Full Text Available Jean-Pierre Lépine1, Mike Briley21Hôpital Lariboisière Fernand Widal, Assistance Publique Hôpitaux de Paris Unité INSERM 705 CNRS UMR 8206, Université Paris Diderot, Paris, France; 2NeuroBiz Consulting and Communication, Castres, FranceAbstract: Recent epidemiological surveys conducted in general populations have found that the lifetime prevalence of depression is in the range of 10% to 15%. Mood disorders, as defined by the World Mental Health and the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, have a 12-month prevalence which varies from 3% in Japan to over 9% in the US. A recent American survey found the prevalence of current depression to be 9% and the rate of current major depression to be 3.4%. All studies of depressive disorders have stressed the importance of the mortality and morbidity associated with depression. The mortality risk for suicide in depressed patients is more than 20-fold greater than in the general population. Recent studies have also shown the importance of depression as a risk factor for cardiovascular death. The risk of cardiac mortality after an initial myocardial infarction is greater in patients with depression and related to the severity of the depressive episode. Greater severity of depressive symptoms has been found to be associated with significantly higher risk of all-cause mortality including cardiovascular death and stroke. In addition to mortality, functional impairment and disability associated with depression have been consistently reported. Depression increases the risk of decreased workplace productivity and absenteeism resulting in lowered income or unemployment. Absenteeism and presenteeism (being physically present at work but functioning suboptimally have been estimated to result in a loss of $36.6 billion per year in the US. Worldwide projections by the World Health Organization for the year 2030 identify unipolar major depression as the leading cause of disease burden

  19. Low level deltamethrin resistance in ticks from cattle of Kerala, a south Indian state.

    Science.gov (United States)

    Jyothimol, G; Ravindran, R; Juliet, S; Ajithkumar, K G; Suresh, N N; Vimalkumar, M B; Lenka, D R; Varghese, S; Ghosh, Srikanta

    2014-08-29

    The deltamethrin resistance status in Rhipicephalus (Boophilus) annulatus and R. (B.) microplus ticks collected from cattle of five organized farms of Kerala, south India was evaluated. Resistance was characterized using biological (larval packet test), biochemical (esterase enzyme activity assay) and molecular tools (PCR amplification and sequencing of deltamethrin resistance-associated genes). Characterization of field isolates revealed level I resistance in ticks collected from four out of five farms. Elevated level of α/β esterase activity was not recorded in isolates showing level I resistance. Previously reported point mutations in the carboxyl esterase (G1120A) and sodium channel (T2134A and C190A) genes were not observed in any of the field isolates. The present study showed a low level (level I) resistance is developed in the most economically important ticks infesting cattle of this state and it cautions the development of large scale resistance in future. PMID:24877788

  20. Estudo comparativo do aspecto da hemolinfa de algumas espécies de carrapatos (Acari, Ixodidae: descrição da variação hemocitária de adultos de Amblyomma cajennense (Fabricius Koch Comparative study of the hemolymph aspect from a few ticks species (Acari, Ixodidae: description of the hemocyte variation of adults of Amblyomma cajennense (Fabricius Koch

    Directory of Open Access Journals (Sweden)

    Maria Elisa Carneiro

    2002-07-01

    Full Text Available The hemocyte composition of adults of Amblyomma cajennense (Fabricius, 1787 Koch, 1844 adults consisted of three basic cellular types: prahemocyte I (PR I, plasmatocyte (PL and spherulocyte (ES II. Among the ixodids observed (A. cajennense; A. dissimile Koch, 1844; Rhipicephalus sanguineus Latreille, 1806; Anocentor nitens (Neumann, 1897 Schulze, 1937; Boophilus microplus Canestrini, 1887 and Haemaphysalis sp. only A. cajennense was different in the adult hemolymph colour. It changed from amber to deep blue as the ixodid age advanced. This fact could be associated with the presence of hemocyanin in the hemolymph and points out the need to develop further investigations about the Ixodidae hemolymph pratein composition as well as the function of all the types found in it. This information could aid the studies on ticks control.

  1. 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

    Directory of Open Access Journals (Sweden)

    M.B. Labruna

    2001-10-01

    Full Text Available 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, Amblyomma ovale (nine ticks on six dogs from four farms and Amblyomma aureolatum (11 ticks on three dogs from one farm. The results are discussed considering the behavior of some dogs used to stroll into the woods and pasture areas whereas other dogs remained closer to the human facilities.

  2. Laboratory Scale Production of Recombinant Haa86 Tick Protein in Pichia pastoris and in Escherichia coli System.

    Science.gov (United States)

    Kumar, Binod; P, Azhahianambi; Ghosh, Srikant

    2016-01-01

    The commercial recombinant Bm86-based vaccines against Rhipicephalus (Boophilus) microplus in Australia (TickGARD™, TickGARD plus™) and in Cuba (Gavac™) provided significant impetus to researchers globally to work on anti-tick vaccines. The Bm86 homologue of Hyalomma anatolicum anatolicum Izatnagar isolate, rHaa86, is considered a potent vaccine candidate against Hyalomma tick species, transmitting animal and human diseases. The two expression systems, prokaryotic, using bacterial expression plasmid vectors and Escherichia coli, and eukaryotic, using methylotrophic yeast Pichia pastoris and yeast expression plasmid vectors, are used in the laboratory level production of rHaa86. Unlike proteins expressed in prokaryotic system, eukaryotic system-expressed proteins are glycosylated and may be a requisite for proper immunogenicity. Here, the protocol for laboratory scale expression of rHaa86 antigen in E. coli and P. pastoris for development of an anti-Hyalomma tick vaccine is described. PMID:27076316

  3. Differential transcription of two highly divergent gut-expressed Bm86 antigen gene homologues in the tick Rhipicephalus appendiculatus (Acari: Ixodida).

    Science.gov (United States)

    Kamau, L; Skilton, R A; Odongo, D O; Mwaura, S; Githaka, N; Kanduma, E; Obura, M; Kabiru, E; Orago, A; Musoke, A; Bishop, R P

    2011-02-01

    The transcriptional control of gene expression is not well documented in the Arthropoda. We describe transcriptional analysis of two exceptionally divergent homologues (Ra86) of the Bm86 gut antigen from Rhipicephalus appendiculatus. Bm86 forms the basis of a commercial vaccine for the control of Rhipicephalus (Boophilus) microplus. The R. appendiculatus Ra86 proteins contain 654 and 693 amino acids, with only 80% amino acid sequence identity. Reverse-transcription PCR of gut cDNA showed transcription of only one genotype in individual female ticks. PCR amplification of 3' untranslated sequences from genomic DNA indicated that both variants could be encoded within a single genome. When both variants were present, one of the two Ra86 genotypes was transcriptionally dominant. PMID:20854482

  4. Bm86 homologues and novel ATAQ proteins with multiple epidermal growth factor (EGF)-like domains from hard and soft ticks☆

    Science.gov (United States)

    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 suggests that the efficacy of a Bm86-based vaccine may be enhanced when based on the orthologous recombinant Bm86 antigen. We therefore identified and analysed the Bm86 homologues from species representing the main argasid and ixodid tick genera, including two from the prostriate Ixodes ricinus tick species. A novel protein from metastriate ticks with multiple epidermal growth factor (EGF)-like domains which is structurally related to Bm86 was identified by using a 3′ rapid amplification of cDNA ends (3′-RACE) method with a degenerate primer based on a highly conserved region of Bm86 and its orthologues. This second protein was named ATAQ after a part of its signature peptide. Quantitative reverse transcriptase-PCR showed that ATAQ proteins are expressed in both midguts and Malpighian tubules, in contrast to Bm86 orthologues which are expressed exclusively in tick midguts. Furthermore, expression of this protein over the life stages of R. microplus and Rhipicephalus appendiculatus was more continuous compared with Bm86. Although a highly effective vaccine antigen, gene silencing of Bm86 by RNA interference (RNAi) produced only a weak phenotype. Similarly the RNAi phenotype of Rhipicephalus evertsi evertsi females in which the expression of Ree86, ReeATAQ or a combination of both genes was silenced by RNAi did not differ from a mock-injected control group. The vaccine potential of ATAQ proteins against tick infestations is yet to be evaluated. PMID:20647015

  5. Bm86 homologues and novel ATAQ proteins with multiple epidermal growth factor (EGF)-like domains from hard and soft ticks.

    Science.gov (United States)

    Nijhof, Ard M; Balk, Jesper A; Postigo, Milagros; Rhebergen, Anne Marie; Taoufik, Amar; Jongejan, Frans

    2010-12-01

    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 suggests that the efficacy of a Bm86-based vaccine may be enhanced when based on the orthologous recombinant Bm86 antigen. We therefore identified and analysed the Bm86 homologues from species representing the main argasid and ixodid tick genera, including two from the prostriate Ixodes ricinus tick species. A novel protein from metastriate ticks with multiple epidermal growth factor (EGF)-like domains which is structurally related to Bm86 was identified by using a 3' rapid amplification of cDNA ends (3'-RACE) method with a degenerate primer based on a highly conserved region of Bm86 and its orthologues. This second protein was named ATAQ after a part of its signature peptide. Quantitative reverse transcriptase-PCR showed that ATAQ proteins are expressed in both midguts and Malpighian tubules, in contrast to Bm86 orthologues which are expressed exclusively in tick midguts. Furthermore, expression of this protein over the life stages of R. microplus and Rhipicephalus appendiculatus was more continuous compared with Bm86. Although a highly effective vaccine antigen, gene silencing of Bm86 by RNA interference (RNAi) produced only a weak phenotype. Similarly the RNAi phenotype of Rhipicephalus evertsi evertsi females in which the expression of Ree86, ReeATAQ or a combination of both genes was silenced by RNAi did not differ from a mock-injected control group. The vaccine potential of ATAQ proteins against tick infestations is yet to be evaluated. PMID:20647015

  6. Increased VLDL in nephrotic patients results from a decreased catabolism while increased LDL results from increased synthesis

    NARCIS (Netherlands)

    de Sain-van der Velden, M; Kaysen, GA; Barrett, HA; Stellaard, F; Gadellaa, MM; Voorbij, HA; Reijngoud, DJ; Rabelink, TJ

    1998-01-01

    Increased very low density lipoprotein (VLDL) in nephrotic patients results from a decreased catabolism while increased low density lipoprotein (LDL) results from increased synthesis. Hyperlipidemias a hallmark of nephrotic syndrome that has been associated with increased risk for ischemic heart dis

  7. Increased skeletal muscle capillarization enhances insulin sensitivity

    DEFF Research Database (Denmark)

    Åkerström, Thorbjörn; Laub, Lasse; Vedel, Kenneth;

    2014-01-01

    Increased skeletal muscle capillarization is associated with improved glucose tolerance and insulin sensitivity. However, a possible causal relationship has not previously been identified. We therefore investigated whether increased skeletal muscle capillarization increases insulin sensitivity......-body insulin sensitivity increased by ~24% and insulin-stimulated skeletal muscle 2-deoxy-[(3)H]-Glucose disposal increased by ~30% concomitant with a ~20% increase in skeletal muscle capillarization. Adipose tissue insulin sensitivity was not affected by the treatment. Insulin-stimulated muscle glucose uptake...... the rats on any other parameters measured. We conclude that an increase in skeletal muscle capillarization is associated with increased insulin sensitivity. These data point towards the importance of increasing skeletal muscle capillarization for prevention or treatment of type 2 diabetes....

  8. The extent of acaricide resistance in 1-, 2- and 3-host ticks on communally grazed cattle in the eastern region of the Eastern Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    Z. Ntondini

    2008-05-01

    Full Text Available In order to determine the extent of acaricide resistance in the eastern region of the Eastern Cape Province 1-, 2- and 3-host ticks were collected from cattle at 59 dip-tanks over a period of 2 years. These ticks were tested for resistance against 3 compounds, namely amitraz, cypermethrin and chlorfenvinphos. The Shaw Larval Immersion Test detected emerging resistance to amitraz in Rhipicephalus (Boophilus microplus at 2 dip-tanks and resistance at a 3rd. It also revealed resistance in this tick to cypermethrin at 1 dip-tank and emerging resistance to chlorfenvinphos at 8 dip-tanks and resistance at 2. Rhipicephalus evertsi evertsi was susceptible to amitraz and cypermethrin at all dip-tanks, but showed emerging resistance to chlorfenvinphos at 7 dip-tanks and resistance at 4. Rhipicephalus appendiculatus was susceptible to amitraz and chlorfenvinphos at all dip-tanks and demonstrated emerging resistance to cypermethrin at 1. With the exception of R. (B. microplus, in which emerging resistance to amitraz was detected at 1 dip-tank by the Reproductive Estimate Test, all 3 tick species at all dip-tanks at which sufficient numbers of ticks had been collected were susceptible to the 3 acaracides in both the Egg Laying Test and the Reproductive Estimate Test. The localities at which acaricide resistance was recorded were mapped.

  9. Performance of two Bm86 antigen vaccin formulation against tick using crossbreed bovines in stall test.

    Science.gov (United States)

    Andreotti, Renato

    2006-01-01

    Cattle tick control remains a serious problem for cattle farms in Brazil due to the limited success achieved with chemicals. In Brazil, the use of vaccines for tick control associated with the use of chemicals and pasture rotation may open possibilities for integrated control. However, it is important to know whether regional Boophilus microplus strains are sensitive to antibodies produced by the available antigens: antigen preparations Gavac™ and TickGard(PLUS). The aim of this research was to evaluate the performance of two Bm86 antigen vaccine formulation against tick using crossbred bovines in stall test antigen against a regional B. microplus strain. The experiment was carried out in central Brazil (20 degrees 27'S, 54 degrees 37'W). A trial was conducted in stall conditions on crossbred cattle under controlled infestation. Two groups of 16 animals each, homogeneous in weight and sex, were vaccinated with Gavac™ or TickGard(PLUS), two groups of eight animals as control. Challenge was performed on three alternate days, with 5,000 larvae each time, beginning 21 days after the second injection. The antibody response was measured by ELISA and vaccinated animals presented immune response considering IgG levels. The results showed 49.2% and 46.4% protection efficacy for Gavac™ and TickGard(PLUS), respectively. PMID:16978472

  10. 3 Ways to Increase Positive Emotions

    Science.gov (United States)

    ... Friend Who Cuts? 3 Ways to Increase Positive Emotions KidsHealth > For Teens > 3 Ways to Increase Positive ... to give yourself a boost. Track Your Positive Emotions Name the positive emotions you're already familiar ...

  11. Increasing ideological tolerance in social psychology.

    Science.gov (United States)

    Inbar, Yoel; Lammers, Joris

    2015-01-01

    We argue that recognizing current ideological diversity in social psychology and promoting tolerance of minority views is just as important as increasing the number of non-liberal researchers. Increasing tolerance will allow individuals in the minority to express dissenting views, which will improve psychological science by reducing bias. We present four recommendations for increasing tolerance.

  12. Resistance status of ticks (Acari; Ixodidae) to amitraz and cypermethrin acaricides in Isoka District, Zambia.

    Science.gov (United States)

    Muyobela, Jackson; Nkunika, Philip Obed Yobe; Mwase, Enala Tembo

    2015-12-01

    This study was designed to obtain data on the farmer's approach to tick control and to determine whether Rhipicephalus appendiculatus Neuman, Amblyomma variegatum (Fabricius), and Rhipicephalus (Boophilus) microplus (Canestrini) were resistant to amitraz and cypermethrin acaricides, in Isoka District, Zambia. Prevailing tick control practices were documented by administering a semi-structured questionnaire to 80 randomly selected smallholder livestock farmers from four agricultural camps (Longwe, Kantenshya, Kapililonga, and Ndeke) in Isoka District. Modified larval packet test (LPT) bioassay experiments were used to determine the resistance status of the common tick species against amitraz and cypermethrin acaricides. Fifty percent of respondents practiced chemical tick control with amitraz (27 %) and cypermethrin (23 %) being the acaricides in use, and were applied with knapsack sprayers. Less than 3 l of spray wash per animal was used which was considerably lower than the recommended delivery rate of 10 l of spray wash per animal. No significant susceptibility change to amitraz at 95 % confidence level was observed in R. appendiculatus and A. variegatum against amitraz. However, a significant change in the susceptibility of R. (Bo.) microplus tested with amitraz was detected at 95 % confidence. The test population had a lower susceptibility (LD50 0.014 %; LD90 0.023 %) than the reference population (LD50 0.013 %; LD90 0.020 %). The results indicated that resistance to amitraz was developing in R. (Bo.) microplus. For cypermethrin, no significant susceptibility change at 95 % confidence was observed in any of the three species and thus resistance to this chemical was not observed.

  13. Resistance status of ticks (Acari; Ixodidae) to amitraz and cypermethrin acaricides in Isoka District, Zambia.

    Science.gov (United States)

    Muyobela, Jackson; Nkunika, Philip Obed Yobe; Mwase, Enala Tembo

    2015-12-01

    This study was designed to obtain data on the farmer's approach to tick control and to determine whether Rhipicephalus appendiculatus Neuman, Amblyomma variegatum (Fabricius), and Rhipicephalus (Boophilus) microplus (Canestrini) were resistant to amitraz and cypermethrin acaricides, in Isoka District, Zambia. Prevailing tick control practices were documented by administering a semi-structured questionnaire to 80 randomly selected smallholder livestock farmers from four agricultural camps (Longwe, Kantenshya, Kapililonga, and Ndeke) in Isoka District. Modified larval packet test (LPT) bioassay experiments were used to determine the resistance status of the common tick species against amitraz and cypermethrin acaricides. Fifty percent of respondents practiced chemical tick control with amitraz (27 %) and cypermethrin (23 %) being the acaricides in use, and were applied with knapsack sprayers. Less than 3 l of spray wash per animal was used which was considerably lower than the recommended delivery rate of 10 l of spray wash per animal. No significant susceptibility change to amitraz at 95 % confidence level was observed in R. appendiculatus and A. variegatum against amitraz. However, a significant change in the susceptibility of R. (Bo.) microplus tested with amitraz was detected at 95 % confidence. The test population had a lower susceptibility (LD50 0.014 %; LD90 0.023 %) than the reference population (LD50 0.013 %; LD90 0.020 %). The results indicated that resistance to amitraz was developing in R. (Bo.) microplus. For cypermethrin, no significant susceptibility change at 95 % confidence was observed in any of the three species and thus resistance to this chemical was not observed. PMID:26310511

  14. Are diseases increasing in the ocean?

    Science.gov (United States)

    Lafferty, Kevin D.; Porter, James W.; Ford, Susan E.

    2004-01-01

    Many factors (climate warming, pollution, harvesting, introduced species) can contribute to disease outbreaks in marine life. Concomitant increases in each of these makes it difficult to attribute recent changes in disease occurrence or severity to any one factor. For example, the increase in disease of Caribbean coral is postulated to be a result of climate change and introduction of terrestrial pathogens. Indirect evidence exists that (a) warming increased disease in turtles; (b) protection, pollution, and terrestrial pathogens increased mammal disease; (c) aquaculture increased disease in mollusks; and (d) release from overfished predators increased sea urchin disease. In contrast, fishing and pollution may have reduced disease in fishes. In other taxa (e.g., sea grasses, crustaceans, sharks), there is little evidence that disease has changed over time. The diversity of patterns suggests there are many ways that environmental change can interact with disease in the ocean.

  15. Taurine increases hippocampal neurogenesis in aging mice

    Directory of Open Access Journals (Sweden)

    Elias Gebara

    2015-05-01

    Full Text Available Aging is associated with increased inflammation and reduced hippocampal neurogenesis, which may in turn contribute to cognitive impairment. Taurine is a free amino acid found in numerous diets, with anti-inflammatory properties. Although abundant in the young brain, the decrease in taurine concentration with age may underlie reduced neurogenesis. Here, we assessed the effect of taurine on hippocampal neurogenesis in middle-aged mice. We found that taurine increased cell proliferation in the dentate gyrus through the activation of quiescent stem cells, resulting in increased number of stem cells and intermediate neural progenitors. Taurine had a direct effect on stem/progenitor cells proliferation, as observed in vitro, and also reduced activated microglia. Furthermore, taurine increased the survival of newborn neurons, resulting in a net increase in adult neurogenesis. Together, these results show that taurine increases several steps of adult neurogenesis and support a beneficial role of taurine on hippocampal neurogenesis in the context of brain aging.

  16. Pension Age Increase: Pro et Contra

    OpenAIRE

    Maleva, T.; Sinyavskaya, O.

    2010-01-01

    Population ageing and growing deficit of Russian pension system place on the agenda an issue of increasing pension age. The article reviews international practices of regulating pension ages. Authors critically discuss the pros and cons of increasing pension ages in Russia from perspectives of demographic situation and trends, labor market, pension system and public attitudes toward this issue. They prove necessity of the effective pension age increasing in Russia and present their views on h...

  17. CO2 Increase: Questions Beyond Climate Change

    OpenAIRE

    Beckmann, G.; Klopries, B.

    1990-01-01

    The increase of the tropospheric C02 (carbon dioxide) concentration is considered by scientists all over the world to be an alarming signal, as becomes evident from the huge amount of literature on the subject. The so-called greenhouse-gas effect, or, more precisely, its anthropogenic component, is mainly caused by the C02 increase. However, other trace gases have also contributed their share. Far-reaching climatic changes, a temperature increase in the tropospheric air, especially in the po...

  18. Familial skin cancer syndromes: Increased melanoma risk.

    Science.gov (United States)

    Ransohoff, Katherine J; Jaju, Prajakta D; Jaju, Prajaka D; Tang, Jean Y; Carbone, Michele; Leachman, Sancy; Sarin, Kavita Y

    2016-03-01

    Phenotypic traits, such as red hair and freckling, increase melanoma risk by 2- to 3-fold. In addition, approximately 10% of melanomas are caused by inherited germline mutations that increase melanoma risk from 4- to >1000-fold. This review highlights the key genes responsible for inherited melanoma, with an emphasis on when a patient should undergo genetic testing. Many genetic syndromes associated with increased melanoma risk are also associated with an increased risk of other cancers. Identification of these high-risk patients is essential for preventive behavior reinforcement, genetic counseling, and ensuring other required cancer screenings.

  19. Does Twitter Increase Perceived Police Legitimacy?

    NARCIS (Netherlands)

    Grimmelikhuijsen, Stephan G; Meijer, Albert J

    2015-01-01

    Social media use has become increasingly popular among police forces. The literature suggests that social media use can increase perceived police legitimacy by enabling transparency and participation. Employing data from a large and representative survey of Dutch citizens (N = 4,492), this article t

  20. Exergames: Increasing Physical Activity through Effective Instruction

    Science.gov (United States)

    Rudella, Jennifer L.; Butz, Jennifer V.

    2015-01-01

    Due to the growing obesity epidemic in the United States, educators must consider new ways to increase physical activity in an effort to address obesity. There are a variety of ways educators can increase physical activity in the classroom, and exergames--video games that require physical movement in order to play--are a modern-day approach to…

  1. Increasing turnover through time in tropical forests

    OpenAIRE

    Phillips, O. L; Gentry, A.H.

    1994-01-01

    Tree turnover rates were assessed at 40 tropical forest sites. Averaged across inventoried forests, turnover, as measured by tree mortality and recruitment, has increased since the 1950's, with an apparent pantropical acceleration since 1980. Among 22 mature forest sites with two or more inventory periods, forest turnover also increased. The trend in forest dynamics may have profound effects on biological diversity.

  2. Wilson's disease; increased aluminum in liver.

    Science.gov (United States)

    Yasui, M; Yoshimasu, F; Yase, Y; Uebayashi, Y

    1979-01-01

    Interaction of trace metal metabolism was studied in a patient with Wilson's dease. Atomic absorption analysis showed markedly increased urinary excretion of copper and aluminum and an increased aluminum content was found in the biopsied liver by neutron activation analysis. These findings suggest a complicated pathogenetic mechanism involving other metals besides copper in the Wilson's disease.

  3. Worldwide Increasing Incidences of Cutaneous Malignant Melanoma

    Directory of Open Access Journals (Sweden)

    Dianne E. Godar

    2011-01-01

    Full Text Available The incidence of cutaneous malignant melanoma (CMM has been increasing at a steady rate in fair-skinned populations around the world for decades. Scientists are not certain why CMM has been steadily increasing, but strong, intermittent UVB (290–320 nm exposures, especially sunburn episodes, probably initiate, CMM, while UVA (321–400 nm passing through glass windows in offices and cars probably promotes it. The CMM incidence may be increasing at an exponential rate around the world, but it definitely decreases with increasing latitude up to ~50°N where it reverses and increases with the increasing latitude. The inversion in the incidence of CMM may occur because there is more UVA relative to UVB for most of the year at higher latitudes. If windows, allowing UVA to enter our indoor-working environment and cars, are at least partly responsible for the increasing incidence of CMM, then UV filters can be applied to reduce the rate of increase worldwide.

  4. Increased muscle glucose uptake during contractions

    DEFF Research Database (Denmark)

    Ploug, Thorkil; Galbo, H; Richter, E A

    1984-01-01

    We reinvestigated the prevailing concept that muscle contractions only elicit increased muscle glucose uptake in the presence of a so-called "permissive" concentration of insulin (Berger et al., Biochem. J. 146: 231-238, 1975; Vranic and Berger, Diabetes 28: 147-163, 1979). Hindquarters from rats...... in severe ketoacidosis were perfused with a perfusate containing insulin antiserum. After 60 min perfusion, electrical stimulation increased glucose uptake of the contracting muscles fivefold. Also, subsequent contractions increased glucose uptake in hindquarters from nondiabetic rats perfused for 1...... Berger et al., 3-O-methylglucose uptake increased during contractions and glucose uptake was negative at rest and zero during contractions. An increase in muscle transport and uptake of glucose during contractions does not require the presence of insulin. Furthermore, glucose transport in contracting...

  5. Why does human culture increase exponentially?

    Science.gov (United States)

    Enquist, M; Ghirlanda, S; Jarrick, A; Wachtmeister, C-A

    2008-08-01

    Historical records show that culture can increase exponentially in time, e.g., in number of poems, musical works, scientific discoveries. We model how human capacities for creativity and cultural transmission may make such an increase possible, suggesting that: (1) creativity played a major role at the origin of human culture and for its accumulation throughout history, because cultural transmission cannot, on its own, generate exponentially increasing amounts of culture; (2) exponential increase in amount of culture can only occur if creativity is positively influenced by culture. The evolution of cultural transmission is often considered the main genetic bottleneck for the origin of culture, because natural selection cannot favor cultural transmission without any culture to transmit. Our models suggest that an increase in individual creativity may have been the first step toward human culture, because in a population of creative individuals there may be enough non-genetic information to favor the evolution of cultural transmission. PMID:18571686

  6. Are increases in cigarette taxation regressive?

    Science.gov (United States)

    Borren, P; Sutton, M

    1992-12-01

    Using the latest published data from Tobacco Advisory Council surveys, this paper re-evaluates the question of whether or not increases in cigarette taxation are regressive in the United Kingdom. The extended data set shows no evidence of increasing price-elasticity by social class as found in a major previous study. To the contrary, there appears to be no clear pattern in the price responsiveness of smoking behaviour across different social classes. Increases in cigarette taxation, while reducing smoking levels in all groups, fall most heavily on men and women in the lowest social class. Men and women in social class five can expect to pay eight and eleven times more of a tax increase respectively, than their social class one counterparts. Taken as a proportion of relative incomes, the regressive nature of increases in cigarette taxation is even more pronounced.

  7. U.S. spending increase planned

    International Nuclear Information System (INIS)

    This article summarizes a paper by Salomon Brothers which published its 14th annual survey and analysis of 1996 worldwide oil and gas exploration and production expenditures. The 28-page report analyzing the December 1995 survey of 275 oil and gas companies indicates the industry is planning a worldwide E and P spending increase of 7.7% this year, over 1995 levels. This is somewhat lower than the now-expected 9.0% increase in 1995 from 1994; however, it is the largest planned increase from a year-end survey since December 1990. Results indicate the recovery in international spending that began in 1995 will be sustained at a more-modest 8.6%, compared to the 14.4% increase last year. Deferrals from 1994 are believed to have contributed to strong 1995 international spending. US spending, conversely, is expected to increase a robust 11.8% in 1996, after a 4.7% advance in 1995. US majors are pacing this increase with a planned 13.4% increase, compared to 9.3% for independents. Canadian operators project a 6.4% decline, even greater than the 4.4% drop registered in 1995

  8. NSF to receive 10% funding increase

    Science.gov (United States)

    Jones, Richard M.

    Work is almost complete on the fiscal year 1994 funding bill for the National Science Foundation. On October 1, Conference Committee Chairs Louis Stokes (D-Ohio) and Barbara Mikulski (D-Md.) and their colleagues completed work on the final version of HR2491, the VA, HUD, Independent Agencies Appropriations Bill. The House and Senate will soon give their final approval to the conference report for HR2491, after which it will lack only the president's signature. NSF's overall budget increase of 10%, raising total funding to %3,005.3 million, is the highest increase among all departments and agencies. Last year's increase in NSF funding was 6.3%.Funding for research and related activities will increase 7% to $1,986 million, a compromise between the 10% House increase and the 4% Senate figure. Last year's bill cut research funding. Education and human resources funding will increase 17% to $569.6 million. This is $13.5 million above the Clinton administration's request. Last year's increase for education and human resources was 4.7%.

  9. Increased skeletal muscle capillarization enhances insulin sensitivity.

    Science.gov (United States)

    Akerstrom, Thorbjorn; Laub, Lasse; Vedel, Kenneth; Brand, Christian Lehn; Pedersen, Bente Klarlund; Lindqvist, Anna Kaufmann; Wojtaszewski, Jørgen F P; Hellsten, Ylva

    2014-12-15

    Increased skeletal muscle capillarization is associated with improved glucose tolerance and insulin sensitivity. However, a possible causal relationship has not previously been identified. Therefore, we investigated whether increased skeletal muscle capillarization increases insulin sensitivity. Skeletal muscle-specific angiogenesis was induced by adding the α1-adrenergic receptor antagonist prazosin to the drinking water of Sprague-Dawley rats (n = 33), whereas 34 rats served as controls. Insulin sensitivity was measured ≥40 h after termination of the 3-wk prazosin treatment, which ensured that prazosin was cleared from the blood stream. Whole body insulin sensitivity was measured in conscious, unrestrained rats by hyperinsulinemic euglycemic clamp. Tissue-specific insulin sensitivity was assessed by administration of 2-deoxy-[(3)H]glucose during the plateau phase of the clamp. Whole body insulin sensitivity increased by ∼24%, and insulin-stimulated skeletal muscle 2-deoxy-[(3)H]glucose disposal increased by ∼30% concomitant with an ∼20% increase in skeletal muscle capillarization. Adipose tissue insulin sensitivity was not affected by the treatment. Insulin-stimulated muscle glucose uptake was enhanced independent of improvements in skeletal muscle insulin signaling to glucose uptake and glycogen synthesis, suggesting that the improvement in insulin-stimulated muscle glucose uptake could be due to improved diffusion conditions for glucose in the muscle. The prazosin treatment did not affect the rats on any other parameters measured. We conclude that an increase in skeletal muscle capillarization is associated with increased insulin sensitivity. These data point toward the importance of increasing skeletal muscle capillarization for prevention or treatment of type 2 diabetes. PMID:25352432

  10. Increasing trends of herpes zoster in Australia.

    Directory of Open Access Journals (Sweden)

    Raina MacIntyre

    Full Text Available Increasing trends in incidence of herpes zoster (HZ have been reported in Australia and internationally. This may reflect the impact of childhood VZV vaccination programs introduced universally in Australia in late 2005. The objective of this study was to evaluate changes in incidence of HZ and PHN in Australia over time, and associated healthcare resource utilisation.Australian data on general practice (GP encounters for HZ, specific antiviral prescribing data from the pharmaceutical benefits scheme, emergency department presentations from the states of NSW and Victoria and national hospitalisation data for HZ were analysed for time trends using regression models. Two time periods (2000-2006 and 2006-2013 were compared which correspond broadly with the pre- and post- universal VZV vaccination period.All data sources showed increasing rates of HZ with age and over time. The GP database showed a significant annual increase in encounters for HZ of 2.5 per 100,000 between 1998 and 2013, and the rates of prescriptions for HZ increased by 4.2% per year between 2002 and 2012. In the 60+ population HZ incidence was estimated to increase from 11.9 to 15.4 per 1,000 persons using GP data or from 12.8 to 14.2 per 1,000 persons using prescription data (p<0.05, between the two periods. Hospitalisation data did not show the same increasing trend over time, except for the age group ≥80 years. Most emergency visits for HZ were not admitted, and showed significant increases over time.The burden of HZ in Australia is substantial, and continues to increase over time. This increase is seen both pre- and post-universal VZV vaccination in 2005, and is most prominent in the older population. The substantial burden of HZ, along with ageing of the Australian population and the importance of healthy ageing, warrants consideration of HZ vaccination for the elderly.

  11. Parasites of cattle in the trans-boundary areas of Ogun State, Nigeria

    International Nuclear Information System (INIS)

    Amblyomma variegatum, 739 (19.68%) were Boophilus decoloratus, 487 (12.97%) were Boophilus microplus, 473 (12.59%) were Amblyomma hebraeum, 41 (1.09%) were Hyalomma spp. and 19 (0.51%) were Amblyomma Haematopinus was the only louse specie identified in this study. They were found on the upper eyelid, inner commissure of the pinna and tip of the tail in 16 animals. Demodex bovis was seen in all the 18 skin nodules, while Dermatophilus congolensis was isolated from all 15-skin scabs collected. The very high parasitic load observed in the animal population in this study is an indication that many parasites enter the country on daily basis via animate vectors. These animals may be carriers of a wide range of economic important diseases, the control of which may be very expensive. This may also result in additional cost of production to the owners of in-contact animals. Since the potential for increasing livestock production in Nigeria can only be fully realized if the animals are adequately protected against major diseases, the animals in border areas should be regularly monitored and screened for diseases of economic and/ or epizootic importance to minimize spread of trans-boundary diseases to the national herd. (author)

  12. Tobacco use increases susceptibility to bacterial infection

    Directory of Open Access Journals (Sweden)

    Demuth Donald R

    2008-12-01

    Full Text Available Abstract Active smokers and those exposed to secondhand smoke are at increased risk of bacterial infection. Tobacco smoke exposure increases susceptibility to respiratory tract infections, including tuberculosis, pneumonia and Legionnaires disease; bacterial vaginosis and sexually transmitted diseases, such as chlamydia and gonorrhoea; Helicobacter pylori infection; periodontitis; meningitis; otitis media; and post-surgical and nosocomial infections. Tobacco smoke compromises the anti-bacterial function of leukocytes, including neutrophils, monocytes, T cells and B cells, providing a mechanistic explanation for increased infection risk. Further epidemiological, clinical and mechanistic research into this important area is warranted.

  13. Who Benefits from a Minimum Wage Increase?

    OpenAIRE

    John W. Lopresti; Mumford, Kevin J.

    2015-01-01

    This paper addresses the question of how a minimum wage increase affects the wages of low-wage workers. Most studies assume that there is a simple mechanical increase in the wage for workers earning a wage between the old and the new minimum wage, with some studies allowing for spillovers to workers with wages just above this range. Rather than assume that the wages of these workers would have remained constant, this paper estimates how a minimum wage increase impacts a low-wage worker's wage...

  14. Impact of Babesia bovis and Babesia bigemina on the production of beef cattle in Uruguay

    Directory of Open Access Journals (Sweden)

    M. A. Solari

    1992-01-01

    Full Text Available 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 babesiosis in the reduction of liveweight gains. The results are shown and discussed in the work. Experiment I: the weight increase of the control group (x = 0,248kg/day, was 23% higher than that of the infected group with Babesia spp (from Uruguay, but significant statistical differences were not found (P < 0,05. These animals were kept in boxes and the food was controlled for 76 days. Experiment II: the incidence of Babesis spp (same strain was studied for 140 on Hereford heifers (n = 14 on natural pastures. The control group obtained x = 25,29kg of liveweight gain and it was 45% higher than that of the infected group, significant statistical difference were found (P < 0,05. Experiments with attenuated strains III: four studies were carried out inoculating B. bovis and B. bigemina in bovines about one year old, in different growth systems, searching for the limit of application. Significant statistical differences between those groups were found during the experiment (about 180 days (P < 0,05. Experiment combining and pathogenic strains IV: the liveweight gain, in immune and challanged group (n = 14 was the same than that of the unchallenged group and did not show significant statistical differences (P < 0,05. However the control challenged group had less weight gain and statistical differences were found (P < 0,05. Although this is a preliminary information, it shows that: (a the incidence of babesiosis on the reduction of weight gains is important; (b the

  15. Tick repellents and acaricides of botanical origin: a green roadmap to control tick-borne diseases?

    Science.gov (United States)

    Benelli, Giovanni; Pavela, Roman; Canale, Angelo; Mehlhorn, Heinz

    2016-07-01

    Arthropods are dangerous vectors of agents of deadly diseases, which may hit as epidemics or pandemics in the increasing world population of humans and animals. Among them, ticks transmit more pathogen species than any other group of blood-feeding arthropods worldwide. Thus, the effective and eco-friendly control of tick vectors in a constantly changing environment is a crucial challenge. A number of novel routes have been attempted to prevent and control tick-borne diseases, including the development of (i) vaccines against viruses vectored by ticks; (ii) pheromone-based control tools, with special reference to the "lure and kill" techniques; (iii) biological control programmes relying on ticks' natural enemies and pathogens; and (iv) the integrated pest management practices aimed at reducing tick interactions with livestock. However, the extensive employment of acaricides and tick repellents still remains the two most effective and ready-to-use strategies. Unfortunately, the first one is limited by the rapid development of resistance in ticks, as well as by serious environmental concerns. On the other hand, the exploitation of plants as sources of effective tick repellents is often promising. Here, we reviewed current knowledge concerning the effectiveness of plant extracts as acaricides or repellents against tick vectors of public health importance, with special reference to Ixodes ricinus, Ixodes persulcatus, Amblyomma cajennense, Haemaphysalis bispinosa, Haemaphysalis longicornis, Hyalomma anatolicum, Hyalomma marginatum rufipes, Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) microplus, Rhipicephalus pulchellus, Rhipicephalus sanguineus and Rhipicephalus turanicus. Eighty-three plant species from 35 botanical families were selected. The most frequent botanical families exploited as sources of acaricides and repellents against ticks were Asteraceae (15 % of the selected studies), Fabaceae (9 %), Lamiaceae (10 %), Meliaceae (5 %), Solanaceae (6

  16. Increased transvascular lipoprotein transport in diabetes

    DEFF Research Database (Denmark)

    Jensen, Jan Skov; Feldt-Rasmussen, Bo; Borch-Johnsen, Knut;

    2005-01-01

    likely were not caused by altered hepatic LDL receptor expression, glycosylation of LDL, small LDL size, or medicine use. CONCLUSIONS: Transvascular LDL transport is increased in patients with diabetes mellitus, especially if systolic hypertension or albuminuria is present. Accordingly, lipoprotein flux......CONTEXT: Diabetes is associated with a highly increased risk of atherosclerosis, especially if hypertension or albuminuria is present. OBJECTIVE: We hypothesized that the increased transvascular lipoprotein transport in diabetes may be further accelerated if hypertension or albuminuria is present......, possibly explaining increased intimal lipoprotein accumulation and thus atherosclerosis. DESIGN: The study was cross-sectional and was performed in 1999-2002. SETTING: The study took place in the referral center. PATIENTS: The patients included 60 with diabetes mellitus (27 with type 1 diabetes and 33...

  17. Increasing incidence of diabetes after gestational diabetes

    DEFF Research Database (Denmark)

    Lauenborg, Jeannet; Hansen, Torben; Jensen, Dorte Møller;

    2004-01-01

    To study the incidence of diabetes among women with previous diet-treated gestational diabetes mellitus (GDM) in the light of the general increasing incidence of overweight and diabetes and to identify risk factors for the development of diabetes....

  18. The ways of SOFC systems efficiency increasing

    Energy Technology Data Exchange (ETDEWEB)

    Demin, A.K.; Timofeyeva, N.

    1996-04-01

    The efficiency of solid oxide fuel cells (SOFCs) is described. This paper considers methods to lift the fuel utilization and/or the average cell voltage with the goal of increasing the cell efficiency by improved cell designs.

  19. Autism overflows: increasing prevalence and proliferating theories.

    Science.gov (United States)

    Waterhouse, Lynn

    2008-12-01

    This selective review examines the lack of an explanation for the sharply increasing prevalence of autism, and the lack of any synthesis of the proliferating theories of autism. The most controversial and most widely disseminated notion for increasing prevalence is the measles-mumps-rubella/thimerosal vaccine theory. Less controversial causes that have been proposed include changes in autism diagnostic criteria, increasing services for autism, and growing awareness of the disorder. Regardless of its causes, the increasing prevalence of autism has put pressure on the field of autism research to generate productive and predictive theories of autism. However, the heterogeneity of brain deficits, impaired behaviors, and genetic variants in autism have challenged researchers and theorists, and despite 45 years of research, no standard causal synthesis has emerged. Research going forward should assume that autism is an aggregation of myriad independent disorders of impaired sociality, social cognition, communication, and motor and cognitive skills.

  20. Increase in the Array Television Camera Sensitivity

    Science.gov (United States)

    Shakhrukhanov, O. S.

    A simple adder circuit for successive television frames that enables to considerably increase the sensitivity of such radiation detectors is suggested by the example of array television camera QN902K.

  1. Acute hypoxia increases the cerebral metabolic rate

    DEFF Research Database (Denmark)

    Vestergaard, Mark Bitsch; Lindberg, Ulrich; Aachmann-Andersen, Niels Jacob;

    2016-01-01

    imaging techniques were used to measure global cerebral blood flow and the venous oxygen saturation in the sagittal sinus. Global cerebral metabolic rate of oxygen was quantified from cerebral blood flow and arteriovenous oxygen saturation difference. Concentrations of lactate, glutamate, N......-acetylaspartate, creatine and phosphocreatine were measured in the visual cortex by magnetic resonance spectroscopy. Twenty-three young healthy males were scanned for 60 min during normoxia, followed by 40 min of breathing hypoxic air. Inhalation of hypoxic air resulted in an increase in cerebral blood flow of 15.5% (p = 0.......058), and an increase in cerebral metabolic rate of oxygen of 8.5% (p = 0.035). Cerebral lactate concentration increased by 180.3% ([Formula: see text]), glutamate increased by 4.7% ([Formula: see text]) and creatine and phosphocreatine decreased by 15.2% (p[Formula: see text]). The N-acetylaspartate concentration...

  2. Increased aldosterone: mechanism of hypertension in obesity.

    Science.gov (United States)

    Flynn, Colleen

    2014-05-01

    The prevalence of both obesity and hypertension are increasing worldwide. Hypertension is a common consequence of obesity. Increased central adiposity is associated with increased aldosterone levels and blood pressure in human beings. A number of small studies have shown an association between obesity-mediated hypertension and mechanisms directly linked to increased levels of aldosterone. These studies have shown a trend toward relatively greater blood pressure reduction using aldosterone-receptor blockers compared with other classes of antihypertensive agents. Other than treatment for weight loss, treatment of hypertension with specific antihypertensive medications that block or reduce aldosterone action are appropriate in obese patients. Further research is needed to understand the exact role of the adipocyte in obesity-mediated hypertension.

  3. Ethanologenic bacteria with increased resistance to furfural

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Elliot Norman; Jarboe, Laura R.; Yomano, Lorraine P.; York, Sean W.; Shanmugam, Keelnatham; Ingram, Lonnie O' Neal

    2015-10-06

    The invention relates to bacterium that have increased resistance to furfural and methods of preparation. The invention also relates to methods of producing ethanol using the bacterium and corresponding kits.

  4. Physical activity increases bone mass during growth

    OpenAIRE

    Karlsson, Magnus K; Nordvist, Anders; Karlsson, Caroline

    2008-01-01

    Background: The incidence of fragility fractures has increased during the last half of the 1900?s. One important determinant of fractures is the bone mineral content (BMC) or bone mineral density (BMD), the amount of mineralised bone. If we could increase peak bone mass (the highest value of BMC reached during life) and/or decrease the age-related bone loss, we could possibly improve the skeletal resistance to fracture. Objective: This review evaluates the importance of exercise as a strategy...

  5. Increasing Engagement with the Library via Gamification

    OpenAIRE

    Barr, Matthew; Munro, Kay; Hopfgartner, Frank

    2016-01-01

    One of the main challenges faced by providers of interactive information access systems is to engage users in the use their systems. The library sector in particular can benefit significantly from increased user engagement. In this short paper, we present a preliminary analysis of a university library system that aims to trigger users' extrinsic motivation to increase their interaction with the system. Results suggest that different user groups react in different ways to such 'gamified' systems.

  6. Does Movie Violence Increase Violent Crime?

    OpenAIRE

    Gordon Dahl; Stefano DellaVigna

    2007-01-01

    Laboratory experiments in psychology find that media violence increases aggression in the short run. We analyze whether media violence affects violent crime in the field. We exploit variation in the violence of blockbuster movies from 1995 to 2004, and study the effect on same-day assaults. We find that violent crime decreases on days with larger theater audiences for violent movies. The effect is partly due to voluntary incapacitation: between 6PM and 12AM, a one million increase in the audi...

  7. Leptin increasing sympathetic nerve outflow in obesity

    OpenAIRE

    Simonds, Stephanie E.; Cowley, Michael A.; Enriori, Pablo J.

    2012-01-01

    Obesity is a global problem and effective drug therapy treatment is still unavailable. Obesity develops due to an imbalance between energy intake and energy expenditure (EE). Understanding what happens to EE in obesity may be the key to developing new treatments for obesity. If EE in obesity can be elevated, it could be a potential therapeutic target. We recently discovered that in baseline conditions obese mice have increased EE, in terms of thermogenesis. However, this increase in EE is not...

  8. Population effects of increased climate variation

    OpenAIRE

    Drake, John M.

    2005-01-01

    Global circulation models predict and numerous observations confirm that anthropogenic climate change has altered high-frequency climate variability. However, it is not yet well understood how changing patterns of environmental variation will affect wildlife population dynamics and other ecological processes. Theory predicts that a population's long-run growth rate is diminished and the chance of population extinction is increased as environmental variation increases. This results from the fa...

  9. DUAL RANDOM MODEL OF INCREASING ANNUITY

    Institute of Scientific and Technical Information of China (English)

    HeWenjiong; ZhangYi

    2001-01-01

    The dual random models about the life insurance and social pension insurance have received considerable attention in the recent articles on actuarial theory and applications. This paper discusses a general kind of increasing annuity based on its force of interest accumulationfunction as a general random process. The dual random model of the present value of the benefits of the increasing annuity has been set, and their moments have been calculated under certainconditions.

  10. Minimum wage increases under straightened circumstances

    OpenAIRE

    Addison, John T.; Blackburn, McKinley L.; Cotti, Chad

    2011-01-01

    Do apparently large minimum wage increases in an environment of recession produce clearer evidence of disemployment effects than is typically observed in the new minimum wage literature? This paper augments the sparse literature on the most recent increases in the U.S. minimum wage, using three different data sets and the two main estimation strategies for handling geographically-disparate trends. The evidence is generally unsupportive of negative employment effects, still less of a 'recessio...

  11. Taurine increases hippocampal neurogenesis in aging mice

    OpenAIRE

    Elias Gebara; Florian Udry; Sébastien Sultan; Nicolas Toni

    2015-01-01

    Aging is associated with increased inflammation and reduced hippocampal neurogenesis, which may in turn contribute to cognitive impairment. Taurine is a free amino acid found in numerous diets, with anti-inflammatory properties. Although abundant in the young brain, the decrease in taurine concentration with age may underlie reduced neurogenesis. Here, we assessed the effect of taurine on hippocampal neurogenesis in middle-aged mice. We found that taurine increased cell proliferation in the d...

  12. Increasing incidence of diabetes after gestational diabetes

    DEFF Research Database (Denmark)

    Lauenborg, Jeannet; Hansen, Torben; Jensen, Dorte Møller;

    2004-01-01

    To study the incidence of diabetes among women with previous diet-treated gestational diabetes mellitus (GDM) in the light of the general increasing incidence of overweight and diabetes and to identify risk factors for the development of diabetes.......To study the incidence of diabetes among women with previous diet-treated gestational diabetes mellitus (GDM) in the light of the general increasing incidence of overweight and diabetes and to identify risk factors for the development of diabetes....

  13. Heterostructure optimization for increasing LED efficiency

    Science.gov (United States)

    Rabinovich, Oleg; Legotin, Sergey; Didenko, Sergey; Yakimov, Evgeniy; Osipov, Yuriy; Fedorchenko, Irina

    2016-05-01

    Computer simulations were performed to increase the quantum efficiency of LED by optimizing the nanoheterostructure (NH). Furthermore, the InGaN and AlGaP NHs for LEDs were optimized. On the basis of the optimum NH, ways to further increase the efficiency and the influence of impurities and indium atoms doped into barriers between quantum wells were investigated. The optimum impurity and indium atom concentrations to achieve higher flux were determined.

  14. The Effect of Increasing Mass upon Locomotion

    Science.gov (United States)

    DeWitt, John; Hagan, Donald

    2007-01-01

    The purpose of this investigation was to determine if increasing body mass while maintaining bodyweight would affect ground reaction forces and joint kinetics during walking and running. It was hypothesized that performing gait with increased mass while maintaining body weight would result in greater ground reaction forces, and would affect the net joint torques and work at the ankle, knee and hip when compared to gait with normal mass and bodyweight. Vertical ground reaction force was measured for ten subjects (5M/5F) during walking (1.34 m/s) and running (3.13 m/s) on a treadmill. Subjects completed one minute of locomotion at normal mass and bodyweight and at four added mass (AM) conditions (10%, 20%, 30% and 40% of body mass) in random order. Three-dimensional joint position data were collected via videography. Walking and running were analyzed separately. The addition of mass resulted in several effects. Peak impact forces and loading rates increased during walking, but decreased during running. Peak propulsive forces decreased during walking and did not change during running. Stride time increased and hip extensor angular impulse and positive work increased as mass was added for both styles of locomotion. Work increased at a greater rate during running than walking. The adaptations to additional mass that occur during walking are different than during running. Increasing mass during exercise in microgravity may be beneficial to increasing ground reaction forces during walking and strengthening hip musculature during both walking and running. Future study in true microgravity is required to determine if the adaptations found would be similar in a weightless environment.

  15. Social Closeness Increases Salivary Progesterone in Humans

    OpenAIRE

    Brown, Stephanie L.; Fredrickson, Barbara L; Wirth, Michelle M.; Poulin, Michael J.; Meier, Elizabeth A.; Heaphy, Emily D.; Michael D. Cohen; Schultheiss, Oliver C.

    2009-01-01

    We examined whether interpersonal closeness increases salivary progesterone. One hundred and sixty female college students (80 dyads) were randomly assigned to participate in either a closeness task with a partner versus a neutral task with a partner. Those exposed to the closeness induction had higher levels of progesterone relative to those exposed to the neutral task. Across conditions, progesterone increase one week later predicted the willingness to sacrifice for the partner. These resul...

  16. An experimental increase in stuttering frequency.

    Science.gov (United States)

    Martin, R R; Haroldson, S K

    1988-06-01

    The purpose of the present experiment was to investigate whether stuttering frequency could be increased from baseline by an experimental condition. Initially, 10 adult stutterers spoke spontaneously while alone. Next, they continued speaking, but with an adult, male conversationalist. Finally, the subjects again spoke while alone. Percent stuttering increased in the conversational situation compared with the baseline (alone) situation, and decreased in the final baseline (alone) situation compared with the conversational situation.

  17. Wind increases leaf water use efficiency.

    Science.gov (United States)

    Schymanski, Stanislaus J; Or, Dani

    2016-07-01

    A widespread perception is that, with increasing wind speed, transpiration from plant leaves increases. However, evidence suggests that increasing wind speed enhances carbon dioxide (CO2 ) uptake while reducing transpiration because of more efficient convective cooling (under high solar radiation loads). We provide theoretical and experimental evidence that leaf water use efficiency (WUE, carbon uptake per water transpired) commonly increases with increasing wind speed, thus improving plants' ability to conserve water during photosynthesis. Our leaf-scale analysis suggests that the observed global decrease in near-surface wind speeds could have reduced WUE at a magnitude similar to the increase in WUE attributed to global rise in atmospheric CO2 concentrations. However, there is indication that the effect of long-term trends in wind speed on leaf gas exchange may be compensated for by the concurrent reduction in mean leaf sizes. These unintuitive feedbacks between wind, leaf size and water use efficiency call for re-evaluation of the role of wind in plant water relations and potential re-interpretation of temporal and geographic trends in leaf sizes. PMID:26714739

  18. Energy in China: Coping with increasing demand

    International Nuclear Information System (INIS)

    Sustaining the increasing energy consumption is crucial to future economic growth in China. This report focuses on the current and future situation of energy production and consumption in China and how China is coping with its increasing domestic energy demand. Today, coal is the most important energy resource, followed by oil and hydropower. Most energy resources are located in the inland, whereas the main demand for energy is in the coastal areas, which makes transportation and transmission of energy vital. The industrial sector is the main driver of the energy consumption in China, but the transport sector and the residential sector will increase their share of consumption in China, but the transport sector and the residential sector will increase their share of consumption by 2020. China's energy intensity decreased during the 1990s, but it is still high in a global comparison. China is projected to increase its energy consumption at least two times between 2000 and 2025. The government has an equal focus on energy conservation and to develop the current energy resources. Coal will continue to be the most important fuel, but the demand for oil, hydropower, natural gas and nuclear power will also increase. The main future challenges are transportation of energy resources within China and securing oil supply, both domestic and imports

  19. Wind increases leaf water use efficiency.

    Science.gov (United States)

    Schymanski, Stanislaus J; Or, Dani

    2016-07-01

    A widespread perception is that, with increasing wind speed, transpiration from plant leaves increases. However, evidence suggests that increasing wind speed enhances carbon dioxide (CO2 ) uptake while reducing transpiration because of more efficient convective cooling (under high solar radiation loads). We provide theoretical and experimental evidence that leaf water use efficiency (WUE, carbon uptake per water transpired) commonly increases with increasing wind speed, thus improving plants' ability to conserve water during photosynthesis. Our leaf-scale analysis suggests that the observed global decrease in near-surface wind speeds could have reduced WUE at a magnitude similar to the increase in WUE attributed to global rise in atmospheric CO2 concentrations. However, there is indication that the effect of long-term trends in wind speed on leaf gas exchange may be compensated for by the concurrent reduction in mean leaf sizes. These unintuitive feedbacks between wind, leaf size and water use efficiency call for re-evaluation of the role of wind in plant water relations and potential re-interpretation of temporal and geographic trends in leaf sizes.

  20. Birch Stands Growth Increase in Western Siberia

    Science.gov (United States)

    Kharuk, Viacheslav I.; Kuzmichev, Valeriy V.; Im, Sergey T.; Ranson, Kenneth J.

    2014-01-01

    Birch (Betula pendula Roth) growth within the Western Siberia forest-steppe was analyzed based on long-term (1897-2006) inventory data (height, diameter at breast height [dbh], and stand volume). Analysis of biometry parameters showed increased growth at the beginning of twenty-first century compared to similar stands (stands age = 40-60 years) at the end of nineteenth century. Mean height, dbh, and stem volume increased from 14 to 20 m, from 16 to 22 cm, and from approx. 63 to approx. 220 cu m/ha, respectively. Significant correlations were found between the stands mean height, dbh, and volume on the one hand, and vegetation period length (r(sub s) = 0.71 to 0.74), atmospheric CO2 concentration (r(sub s) = 0.71 to 0.76), and drought index (Standardized Precipitation-Evapotranspiration Index, r(sub s) = -0.33 to -0.51) on the other hand. The results obtained have revealed apparent climate-induced impacts (e.g. increase of vegetation period length and birch habitat drying due to drought increase) on the stands growth. Along with this, a high correlation of birch biometric parameters and [CO2] in ambient air indicated an effect of CO2 fertilization. Meanwhile, further drought increase may switch birch stand growth into decline and greater mortality as has already been observed within the Trans-Baikal forest-steppe ecotone.