Thesis (MTech (Horticulture))--Cape Peninsula University of Technology, 2018. / Ticks and tick-borne diseases are important limiting factors to the attainment of sustainable animal and human health, affecting livelihood of resource poor farming communities in developing countries. Rhipicephalus appendiculatus and Amblyomma variegatum (Ixodidae) are among the most troubling tick species in Africa. While ticks can be controlled by applying chemical acaricides, these chemicals are quite expensive, especially, for small-scale famers in developing countries. Hence, the quest for alternative tick control over the years have revealed that entomopathogenic fungi (EPF) and plant extracts have huge prospects as sustainable alternatives for tick control. Beauveria bassiana (Hypocreales) is a fungal entomopathogen with the ability to colonize plants endophytically and induce secondary metabolite production in plants, and it has been found to be a potential biological control agent against a wide range of arthropods. Several plant species including plant species belonging to the family Alliaceae possess anti-tick activities (repellent and toxic); therefore, integrating the two strategies by inoculating Tulbaghia violacea with B. bassiana could enhance secondary metabolite contents in extracts obtained from the plant and increase medicinal materials. The primary purpose of the present study was to evaluate the effect of indigenous endophytic entomopathogens inoculation of T. violacea on the plant growth, tissue nutrient contents and secondary metabolites, and anti-tick activities of extracts of T. violacea. The specific objectives were: (i) to carry out a study on the effects of inoculating T. violacea with fungal strains of B. bassiana and Clonostachys rosea on plant growth and tissue nutrient contents in extracts of T. violacea with the view of selecting one of the two fungi for further investigation (ii) to compare secondary metabolite profiles of extracts obtained from plants exposed to fungus (EPF) inoculum and control treatment during cultivation, and (iii) to determine whether exposure of T. violacea to an endophytic fungus (B. bassiana) during cultivation affects the repellent and acaricidal activities of extracts of T. violacea on A. variegatum and R. appendiculatus. The study had two experiments, presented in chapters two and three. In the first experiment, eight weeks old potted seedlings of T. violacea were inoculated separately with B. bassiana (strain SM3) and C. rosea (strain SM8) conidia suspended at concentrations of 1 x 106 conidia mL-1. Plant growth parameters, such as number of leaves, plant height (aerial part), fresh weights of aerial parts, and tissue nutrient contents were assessed. Results indicated that B. bassiana induced higher growth of plants than C. rosea. Inoculation with B. bassiana did not significantly (P ˃ 0.05) influence most of the growth parameters, number of leaves, fresht weight of roots and of fresh weight aerial parts (leaves) of T. violacea assessed in the current study. However, mean plant heights and root lengths were significantly (P < 0.05) higher in favour of B. bassiana treated plants compared to those in C. rosea. Fe contents in the roots (1416.3 ± 305.10 mg/kg) were found to be positively influenced (P < 0.05) by the fungal inoculation. There was a significant difference in roots (P < 0.05) on the uptake of Mn in C. rosea treated plants (243 ± 19 mg/kg) compared to the control group (169 ± 16.37 mg/kg) and B. bassiana treated roots (161.3 ± 14.44 mg/kg). Macro nutrients up take did not differ significantly among treatments on both leaves and roots (P > 0.05).

Orientador: Gervásio Henrique Bechara / Banca: Romário Cerqueira Leite / Banca: Rosângela Zacarias Machado / Resumo: No presente estudo avaliou-se o desenvolvimento de resistência a ninfas do ixodídeo Amblyomma cajennense, induzida por infestações controladas, e a possível existência de reatividade cruzada com Amblyomma hebraeum. Para tal, caprinos sem contato prévio com carrapatos, com seis meses de idade, machos ou fêmeas, foram infestados três vezes sucessivamente com ninfas de A. cajennense. Ademais, outro grupo de caprinos foi infestado nas mesmas condições com ninfas de A. hebraeum e colhidos soros para pesquisa de possível reatividade cruzada com A. cajennense. Observou-se que caprinos desenvolveram resistência apenas parcial a ninfas de A. cajennense, como demonstrado pela alteração significativa dos seguintes parâmetros biológicos das ninfas, em relação à primoinfestação: redução de 41,7% e 37,1% no peso de ingurgitamento, respectivamente na 2ª e 3ª infestações; aumento de 20% no período de ecdise e redução de 25,7% na taxa de ecdise, respectivamente nas 3ª e 2ª infestações. Não houve alteração no período de ingurgitamento nem na porcentagem de recuperação de ninfas com as infestações sucessivas. A reação cutânea induzida pelas ninfas de A. cajennense durante as infestações em caprinos caracterizou-se por infiltrado de células inflamatórias, predominantemente neutrófilos e basófilos, estas últimas envolvidas na imunidade a carrapatos por meio de hipersensibilidade basofílica cutânea. Células apresentadoras de antígeno, nomeadamente macrófagos, linfócitos B e células dendríticas foram detectadas por imunoistoquímica em linfonodos drenantes de locais de fixação dos carrapatos, em maior número nos linfonodos dos animais infestados... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study evaluated the acquision of resistance against Amblyomma cajennense nymphs in naïve goats, induced by repeated and controlled infestations, and a possible cross-reactivity with A. hebraeum. Ten naive goats, of both sexes, aged six months were used throughout the experiment. Animals were infested artificially thrice, 30 days intervals between infestations. In addition, goats were infested at same conditions with the tick A. hebraeum as well. Sera from these animals were collected looking for possible cross-reactivity between antigens from these ixodids. It was observed that goats developed partially resistance to A. cajennense nymphs from the 1st infestation on as shown by changes in some biological parameters, as follows: increase of 41.7% and 37.1% in engorgement weight, respectively at the 2nd and 3rd infestations, decrease in 25.7% in nymph’s ecdise rate and increase of 20% in ecdise period, respectively at the 3rd and 2nd infestations. It was not observed alterations in engorgement period and percentage of yielded nymphs. Biopsies of tick bite lesions induced by A. cajennense nymphs during infestations in goats were characterized by inflammatory reaction with cellular influx by neutrophils and basophils predominantly, being the last one involved in the well-known cutaneous basophilia. Antigen presenting cells like macrophages, B-lymphocytes and dendritic cells were detected by immunohistochemical analysis of lymph nodes draining tick infested areas. It should be stressed that these cells were found in higher numbers at lymph nodes from infested goats than from the naïve ones. Western blotting analysis of nymphal A. cajennense extracts revealed shared polypeptides (160, 90 and 16kDa) when used sera from goats infested with A. cajennense either A. hebraeum, indicating cross reactivity between these two tick species. / Mestre

A Febre Maculosa Brasileira (FMB) é uma doença infecciosa causada por Rickettsia rickettsii, transmitida pelo carrapato-estrela Amblyomma sculptum no interior do estado de São Paulo, onde equinos e capivaras são utilizados como sentinelas para FMB por serem considerados hospedeiros primários deste carrapato. Objetivou-se com este trabalho verificar a ocorrência de anticorpos anti-Rickettsia rickettsii em sentinelas clássicos (equinos) e potenciais (ovinos, bovinos e gambás) para FMB que vivem em diferentes ambientes do Campus \"Luiz de Queiroz\", da Universidade de São Paulo, em Piracicaba-SP. De fevereiro de 2017 a janeiro de 2018 foram amostrados 156 hospedeiros, 48 que habitam áreas urbanas, sem a presença ou trânsito de capivaras (15 equinos e 33 gambás), 60 ovinos que frequentam pastagens sem presença de capivaras, mas adjacentes a matas ciliares ocupadas pelos roedores, e 48 que frequentam pastagens por onde transitam capivaras (31 bovinos e seis equinos) ou matas ciliares ocupadas pelos roedores (11 gambás). Quando possível, a amostragem envolveu a coleta de ectoparasitos. O soro obtido após centrifugação do sangue colhido foi analisado em duas etapas, triagem e titulação, pela reação de imunofluorescência indireta (RIFI). Na triagem todas as amostras foram testadas contra R. rickettsii, e consideradas positivas se apresentassem título de anticorpos >= 64. As amostras positivas foram diluídas na etapa de titulação e testadas contra R. rickettsii, R. parkeri, R. bellii, R. ambyommatis e R. rhipicephali para determinação do título máximo de anticorpos para cada espécie. Das 156 amostras testadas, 15 estavam soropositivas, 1/60 ovinos, 1/31 bovinos, 7/21 equinos e 6/44 gambás; os títulos finais variaram de 64 a 4.096. Foi possível determinar o possível antígeno envolvido em reação homóloga (PAERH) em seis amostras, um equino (R. bellii) e quatro gambás e um ovino (R. rickettsii). Foram registrados os carrapatos Amblyomma ovale, Amblyomma dubitatum, Amblyomma sculptum, Dermacentor nitens e Rhipicephalus microplus, e as pulgas Ctenocephalides felis e Siphonaptera: Rhopalopsyllidae cf. Rhopalopsyllus nos hospedeiros amostrados. Conclui-se que equinos e gambás podem ser utilizados como sentinelas para FMB no Campus \"Luiz de Queiroz\", mas os ovinos não. Não foi possível concluir se os bovinos podem ser utilizados com esta função. R. bellii, ou um microrganismo muito semelhante, ocorre na área urbana do Campus \"Luiz de Queiroz\" e é capaz de infectar cavalos. R. rickettsii, ou um microrganismo muito semelhante, ocorre no Campus \"Luiz de Queiroz\" em áreas de permanência e trânsito de capivaras / Brazilian Spotted Fever (BSF) is an infectious disease caused by Rickettsia rickettsii, transmitted by the tick Amblyomma sculptum outside the metropolitan region in the State of São Paulo, where horses and capybaras are used as sentinels for BSF as they are considered primary hosts for this tick. This survey aimed to verify the occurrence of antibodies against Rickettsia rickettsii in sentinels (horses) and potential sentinels (sheep, cattle and opossums) for BSF that lives in different environments of the \"Luiz de Queiroz\" Campus, University of São Paulo, in Piracicaba, SP, Brazil. A total of 156 host were sampled between February of 2017 and January of 2018; 48 that live in urban areas, with no presence or transit of capybaras (15 horses and 33 opossums), 60 sheep that regularly graze on capybara-free pastures adjacent to a riparian forest occupied by these rodents, and 48 that occupy, cross or regularly graze on pastures (31 cows and six horses) or riparian forests (11 opossums) that are areas used by capybaras. Whenever possible, host sampling included ectoparasites collection. Sera obtained after centrifugation of the collected blood was analyzed in two steps, screening and titration, by the indirect immunofluorescence assay technique (IFA). All samples were tested against R. rickettsii during the screening, and those that presented antibodies titers >= 64 were considered positive. Positive samples were diluted during titration and tested against R. rickettsii, R. parkeri, R. bellii, R. ambyommatis and R. rhipicephali for determination of maximum antibodies titers for each species. Of the 156 tested samples, 15 were seropositive, 1/60 sheep, 1/31 cows, 7/21 horses and 6/44 opossums; antibodies endpoint titers ranged from 64 to 4.096. Possible antigen involved in a homologous reaction (PAIHR) was determined for six samples, one horse (R. bellii), four opossums and one sheep (R. rickettsii). The ticks Amblyomma ovale, Amblyomma dubitatum, Amblyomma sculptum, Dermacentor nitens and Rhipicephalus microplus, and the fleas Ctenocephalides felis and Siphonaptera: Rhopalopsyllidae cf. Rhopalopsyllus were collected from the sampled hosts. Results showed that horses and opossums may be used as sentinels for BSF in the \"Luiz de Queiroz\" Campus, but the sheep do not. It wasn\'t possible to determine if the cows may be used as sentinels. R. bellii, or a very closely related microorganism, occurs in the urban area of the \"Luiz de Queiroz\" Campus and is capable to infect horses. R. rickettsii, or a very closely related microorganism, occurs in capybara-transit areas of the \"Luiz de Queiroz\" Campus

Made available in DSpace on 2016-04-28T20:16:32Z (GMT). No. of bitstreams: 1 1997 - Armando de Lemos Ribeiro.pdf: 1637429 bytes, checksum: 67368e92ac3e601a127f511f61aef35b (MD5) Previous issue date: 1997-12-16 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The first experiment was set up to measure the drop-off rhythm of larvae and nymphs of Amblyomma cajennense feeding on the rabbits as experimental hosts. Infestations were carried out with unfed larvae and nymphs aging 15 and 45 days post eclosion and host larval moulting, respectively. Three rabbits were infested with approximately 825 larvae (50 mg of eggs) and 100 nymphs for each age totaling 12 rabbits. Each host were examined at 8, 12, 16 and 24 hours and the dropped larvae and nymphs collected. Regardless of age and instar higher drop-off rhythm were observed from 8 to 16 hours: 73,6 and 72,8% larvae with 15 and 45 days post eclosion and 69,6 and 57,5 nymphs with 15 and 45 days post larval moulting, respectively. The second experiment was set up to evaluate the effect of age on the attachment of larvae and nymphs of Amblyomma cajennense using the rabbit as experimental host. Infestations were carried out with unfed larvae aging from 0-4 to 150 days post-eclosion and unfed nymphs aging from 0-2 to 165 days post-larval moulting. A total of 11 and 12 infestations respectively for larvae and nymphs with 15 days interval were monitored. Three rabbits were infested with 825 larvae and 100 nymphs per rabbit at each interval. Larvae and nymphs with 0-2 day post-eclosion and post larval moulting were able to attach and feed at rates of 45 and 77%. Higher attachment rates for larva (> 70%) were observed from days 15 to 60 post eclosion. Then, start to decrease until 25% at 150 days post-eclosion. Higher attachment rates for nymphs were observed from days 15 to 90 post moulting (> 80%). Then, start to decrease until 36% at 165 days. The periods of attachment and ecdisis, and the percentage of ecdisis were similar for both stages regardless the age prior attachment. When the period of pre-ecdisis is analyzed one might note a shortening as the nymphs because older whereas it was similar for larvae in ali evaluated ages. This third experiment was conduct as an attempt to correlate the weight pre-ecdisis period and timing of drop-off of nymphs with the forecast of the sexes in adults of Rhipicephalus sanguineus. The mean weight of nymphs that moulted to males (n = 96) was 1,97 ? 0,97 and 2,52 ? 0,90 to females (n = 103) (P > 0,05) between the weight of nymphs can not be used to forecast the sexes due to overlapping of to weight ranges. The pre-ecdisis periods were 15,13 ? 0,94 and 14,60 ? 0,77 days for nymphs that moulted to males (n = 96) and females (n = 103) (P > 0,05) respectively. Nymphs (n = 50) that dropped-off on both third and fourth day (mode) post-infestation moulted to 29 females and 21 males whereas those (n = 50) that dropped-off on the fifth day post-infestation moulted to 30 females and 20 males (x2 > 0,05). Although there are numerical differences in ali evaluated parameters none can be used to forecast the sexes in R. sanguineus due to an extensive overlapping. / O primeiro experimento foi montado para avaliar o ritmo de queda de larvas e ninfas de Amblyomma cajennense alimentadas em coelhos. Infesta??es foram feitas com larvas e ninfas em jejum com idades de 15 e 45 dias ap?s eclos?o e ecdise larval respectivamente. Tr?s coelhos foram infestados com aproximadamente 825 larvas (50 mg de ovos) e 100 ninfas para cada idade totalizando 12 coelhos. Cada hospedeiro foi examinado nos hor?rios de 8, 12, 16 e 24 horas e as larvas e ninfas desprendidas foram coletadas. Independente da idade e do instar, o maior n?mero se desprendeu entre 8 e 16 horas: 73,6% e 72,8% para larvas com 15 e 45 dias ap?s eclos?o e 69,6% e 57,5% para ninfa. Com 15 e 45 dias ap?s ecdise larval, respectivamente. O segundo experimento teve como objetivo avaliar o efeito da idade sobre a fixa??o de larvas e ninfas de Amblyomma cajennense, usando o coelho como hospedeiro. Infesta??es foram feitas com larvas com per?odos de jejum de zero a 4 at? 150 dias ap?s eclos?o e ninfas em jejum variando de zero a 2 at? 165 dias ap?s ecdise larval. Um total de 11 e 12 infesta??es para larvas e ninfas respectivamente, com intervalos de 15 dias foram acompanhados. Tr?s coelhos foram infestados com 825 larvas e 100 ninfas por coelhos e para cada tratamento. Larvas e ninfas com zero a 4 dias ap?s eclos?o e zero a 2 dias ap?s ecdise larval se fixaram e se alimentaram, com taxas de recupera??o de 45 e 77% respectivamente. Taxas de recupera??o alta para larvas (> 70%) foi observado para 15 at? 60 dias ap?s eclos?o. Entretanto a partir da? come?ou a decrescer para 25% at? 150 dias p?s-eclos?o. As taxas de recupera??o foram altas para ninfas com 15 at? 90 dias p?s-ecdise (> 80%). Ent?o, come?ou a decrescer para 36% at? 165 dias. Os per?odos de pr?-ecdise, de ecdise e as percentagens de ecdise foram est?veis para todas as idades estudadas. Quando o per?odo de pr?-ecdise ? analisado nota-se um encurtamento conforme as ninfas se tornam mais velhas; ao contr?rio este per?odo foi similar para larvas de todas as idades. Esse terceiro experimento foi conduzido para se observar a correla??o entre o peso, o per?odo de pr?-ecdise e o per?odo de queda de ninfas ingurgitadas com a previs?o do sexo dos adultos de Rhipicephalus sanguineus. A m?dia do peso de ninfas que originaram machos (n = 96) foi de 1,97 ? 0,97 e 2,52 ? 0,90 para f?meas (n = 103) (P > 0,05). O peso das ninfas n?o pode ser usado para a previs?o dos sexos devido ? superposi??o dos pesos. O per?odo de pr?-ecdise foi de 15,13 ? 0,94 e 14,60 ? 0,77 dias par ninfas que originaram machos (n = 96) e f?meas (n = 103) (P > 0,05), respectivamente. Ninfas (n = 50), dos per?odos de queda, inicial (3? dia) e modal (4? dia), desprenderam-se 29 f?meas e 21 machos, em ambos per?odos. No per?odo final (5? dia) (n = 50) desprenderam-se 30 f?meas e 20 machos (x2 > 0,05). Embora exista diferen?as num?ricas em todos os par?metros avaliados, tais par?metros n?o podem ser utilizados para a previs?o dos sexos em R. sanguineus devido a amplitude da superposi??o.

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Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xv, 126 p.; also includes graphics (some col.). Includes bibliographical references (p. 96-107). Available online via OhioLINK's ETD Center

Ticks are hematophagous ectoparasites capable of transmitting various pathogens, including bacteria, protozoa, and viruses, to vertebrates. In the United States, tick-borne pathogens are responsible for around 95% of arthropod-borne diseases. Lyme disease is the most common tick-borne illness. However, emerging tick-borne viruses such as Bourbon virus (BRBV), Powassan virus (POWV), and Heartland virus (HRTV) can cause more severe health problems, including death and neurological abnormalities. The reports of molecular detection of viral RNA in field-collected ticks and serological evidence in a pilot study of wildlife species suggest the presence of these emerging viruses in Virginia. The presence poses a serious health threat, but the extent of their presence or circulation in Virginia is unknown. The objectives of the research are (1) to determine the evidence of circulation of POWV, HRTV, and BRBV in Virginia through serological assessment of domestic and wild animals in Virginia and (2) estimate transmission parameters and the basic reproduction number underlying tick-borne virus distribution and prevalence via a mathematical model. Here, we discuss the known literature relevant to tick-borne virus emergence; we assessed the presence of specific neutralizing antibodies against POWV, HRTV, and BRBV in wildlife and livestock sera collected from different health planning regions in Virginia. We used a susceptible-infected-susceptible (SIS) ordinary differential equation model to estimate transmission parameters that best describe the disease dynamics of emerging tick-borne viruses in Virginia. In our study, wildlife sera were seropositive against POWV (18%), BRBV (8%), and HRTV (5%). A wide range of different wildlife species were shown to be exposed to each virus examined. Livestock are also exposed to tick-borne viruses, with seroprevalences of 1%, 1.2%, and 8% detected in cattle for POWV, BRBV, and HRTV, respectively. We estimated the transmission rate and basic reproduction number to be 1.57 and 0.645, respectively. In conclusion, there is a widespread circulation of tick-borne viruses in western and northern Virginia within diverse species of animal populations. / Master of Science in Life Sciences / Ticks are blood-sucking ectoparasites that can transmit various pathogens, including bacteria, protozoa, and viruses, to humans and other vertebrates. In the United States, tick-borne pathogens are responsible for about 95% of all arthropod-borne disease cases. Lyme disease is the most common tick-borne illness. However, emerging tick-borne viruses such as Bourbon virus (BRBV), Powassan virus (POWV), and Heartland virus (HRTV), can cause more severe health problems, including potentially death or neurological abnormalities. The reports of molecular detection of viral RNA in field-collected ticks and serological evidence in a pilot study of wildlife species suggest the presence of these emerging viruses in Virginia. However, there is a lack of knowledge on the extent of their circulation. Firstly, this study aims to determine the evidence of circulation of POWV, HRTV, and BRBV in Virginia through serological assessment of domestic and wild animals. Secondly, this study aims to estimate transmission parameters and calculate the basic reproduction number of emerging tick-borne viruses. Evidence of prior infection against all three tick-borne viruses was detected in both wild and domestic animal species from the five Virginia health planning regions, with most samples in the study coming from southwestern and northwestern regions. In conclusion, there is a circulation of tick-borne viruses in Virginia, which is a potential threat to the public health.

Made available in DSpace on 2014-07-29T15:30:42Z (GMT). No. of bitstreams: 1 Dissertacao WalmirtonBezerra.pdf: 3515322 bytes, checksum: 262c3d8c28e9609dbeee4234b3332f81 (MD5) Previous issue date: 2008-10-22 / Amblyomma cajennense (Fabricius, 1787) (Acari, Ixodidae) known as tick-star , is a ixodid heteroxenous tree-host found too often in horses. Have little specific parasite, particularly in periods of larvae and nymph, is considered the most important in ixodid transmission of spotted fever to humans in Brazil. Rhipicephalus sanguineus, tick ectoparasite mainly from domestic dogs in urban areas, but also parasite other mammals, birds and reptiles, is responsible for the transmission of pathogens to their hosts. By developing in synanthropic environments, with their immature stages occasionally infecting man, this ixodídeo could cause increased incidence of erliquiosis, babesiosis and spotted fever in humans. The difficulties in controlling these ixodids, including the development of resistance to some acaricides chemicals synthetic main products used in their control, studies to encourage development of alternative measures, more efficient and less environmental impact. The objective of this work was monitoring the susceptibility and/or resistance of R. sanguineus to 14 insecticide products/acaricides, among the most acaricide sold in Goiás for control of ectoparasites of medical and veterinary importance, and verify the potential of substances extracted from plants, Carapa guianensis AUBLET (Meliaceae), Piper hispidinervum C.DC. (Piperaceae) and Magonia pubescens St. Hil. (Sapindaceae) in botanical exploration of acaricides for control of A. cajennense and R. saguineus. Engorged female of R. sanguineus were collected in environments naturally infested frequented by dogs in different districts and municipalities of Goiânia. Engorged female of A. cajennense were collected on horses from rural farms of different neighborhoods and surrounding municipalities of Goiânia. In the laboratory they were washed with distilled water, dried with paper towel and put in incubators B.O.D., to conduct the oviposition. Envelopes were used to filter paper impregnated with different concentrations of synthetic chemical acaricides, of essential oils from the leaves and branches side of P. hispidinervum, essential oil coming seeds of C. guianensis and stem bark of M. pubescens. In the control group used up only distilled water and solvent. Bioassays were made in quadruplicate. In the first study, Lethal Concentrations, CL50 and CL99, after 24 h and 48 h of exposure were calculated for the products that caused a framework for possible resistance or resistance to larvicidal R. sanguineus, according to WHO criteria. There was a framework of resistance to the basic products of Cypermethrin, Cypermethrin + Piperonyl Butoxide (PBO), Deltamethrin, Permethrin and Amitraz in 24 h presenting mortalities of 58.36%, 71.36%, 48.7%, 64.5% and 77.8%, respectively. In 48 h of exposure to Amitraz the mortality rate was 88%, presenting a framework for possible resistance accounting for 0.07% of the products tested. The lethal concentrations CL50 and CL99 were: Cypermethrin (0.06% and 7.04%), Cypermethrin + PBO (0.06% and 2.1%), Deltamethrin (0.06% and 1.57%); Permethrin (0.06% and 0.3%), Amitraz 24 h (0025% and 0.73%) and Amitraz 48 h (0.06% and 0.31%). The products Deltamethrin, Cypermethrin, Permethrin, Cypermethrin + PBO and Amitraz (24 and 48 h of exposure) were 35.2, 21, 7.85, 3, 3.65, 1.55 times, respectively, higher than the dosages recommended by manufacturers. In the second study noted that the essential oil of C. guianensis on the larvae of A. cajennense resulted in 24 h, mortality not exceeding 10% for 35% concentration in 48 h of exposure received at the CL50 of 7.38% and 45.45% of CL99, the essential oil of P. hispidinervum shown in 24 h of exposure CL50 of 0.42% and CL99 of 0.88%, in 48 h of exposure CL50 of 0.45% and CL99 of 1.06%. There was Knock down the effect on the larvae of A. cajennense the essential oil of P. hispidinervum, significantly influencing mortality average. In the third study there was the lethal action of ethanol crude extract of stem of bark M. pubescens on R. sanguineus, in the reading of 48 h LC50 and CL99 was 0.15% and 0.99%, respectively.The plants showed larvicidal effect on A. cajennense and R. sanguineus. The essential oils and extracts studied demonstrated greatest potential for the exploration of acaricides plants, with less environmental impact, to be used as a strategy for control of R. sanguineus and A. cajennense. / Amblyomma cajennense (Fabricius, 1787) (Acari, Ixodidae) conhecido como carrapato-estrela , é um ixodídeo heteroxeno encontrado com muita freqüência em eqüídeos. Têm pouca especificidade parasitária, principalmente nos estágios de larva e ninfa, sendo considerado o ixodídeo mais importante na transmissão da febre maculosa para os humanos no Brasil. Rhipicephalus sanguineus, carrapato ectoparasita principalmente dos cães domésticos em áreas urbanizadas, mas que também parasita outros mamíferos, aves e répteis, é responsável pela transmissão de patógenos aos seus hospedeiros. Por se desenvolver em ambientes sinantrópicos, com seus estágios imaturos, parasitando ocasionalmente o homem, este ixodídeo poderá vir a causar aumento na incidência de erliquiose, babesiose e febre maculosa no homem. As dificuldades existentes no controle dos ixodídeos, incluindo o desenvolvimento de resistência a alguns acaricidas químicos sintéticos, principais produtos utilizados em seu controle, incitam estudos para desenvolvimento de medidas alternativas, mais eficientes e de menor impacto ambiental. O objetivo do presente trabalho foi monitorar a susceptibilidade e/ou resistência de R. sanguineus a 14 produtos inseticidas/acaricidas, dentre os mais comercializados em Goiás para controle de ectoparasitos de importância médica e veterinária, e verificar a potencialidade de substâncias extraídas das plantas Carapa guianensis AUBLET (Meliaceae), Piper hispidinervum C.DC. (Piperaceae) e Magonia pubescens St. Hil. (Sapindaceae), na prospecção de acaricidas botânicos para controle de A. cajennense e R. sanguineus. As teleóginas de R. sanguineus foram coletadas, em ambientes naturalmente infestados, freqüentados por cães, de diferentes bairros e municípios de Goiânia. Teleóginas de A. cajennense foram coletadas em cavalos oriundos de propriedades rurais de diferentes bairros e municípios circunvizinhos de Goiânia. No laboratório, as teleóginas foram lavadas com água destilada, secas em papel toalha e acondicionadas em incubadoras B.O.D., para realizarem a oviposição. Foram utilizados envelopes de papel filtro impregnados com diferentes concentrações dos acaricidas químicos sintéticos, óleo essencial provenientes das folhas e ramos secundários de P. hispidinervum, óleo essencial provindo das sementes de C. guianensis e o extrato bruto etanólico da casca do caule de M. pubescens. No grupo controle utilizou-se apenas água destilada e solvente. Os bioensaios foram realizados em quadruplicata. No primeiro estudo, Concentrações Letais, CL50 e CL99, após 24 h e 48 h de exposição foram calculadas para os produtos que proporcionaram um quadro de resistência ou possível resistência larvicida para R. sanguineus, segundo critérios da OMS. Observou-se resistência para as larvas de R. sanguineus produtos que apresentaram mortalidades a base de Cipermetrina (58,36%), Cipermetrina + Butóxido de Piperolina (PBO) (71,36%), Deltametrina (48,7%), Permetrina (64,5%) e Amitraz (77,8%) nas 24 h, correspondendo a 36% dos produtos testados. Em 48 h de exposição ao Amitraz a mortalidade foi de 88%, apresentando um quadro de possível resistência, correspondendo a 0,07% dos produtos testados. As concentrações letais CL50 e CL99 encontradas foram: Cipermetrina (0,06% e 7,04%), Cipermetrina + PBO (0,06% e 2,1%), Deltametrina (0,06% e 1,57%), Permetrina (0,06% e 0,3%), Amitraz 24 h (0,025% e 0,73%) e Amitraz 48 h (0,06% e 0,31%). Os produtos Deltametrina, Cipermetrina, Permetrina, Cipermetrina + PBO e Amitraz (24 e 48 h de exposição), foram 35,2; 21; 7,85; 3; 3,65; 1,55 vezes, respectivamente, maiores do que as dosagens recomendadas pelos fabricantes. No segundo estudo observou-se o efeito letal do óleo essencial de C. guianensis sobre as larvas de A. cajennense ocasionando nas 24 h, mortalidade não superior a 10% para concentração 35%, nas 48 h de exposição obtiveram-se as CL50 de 7,38% e CL99 de 45,45%. O óleo essencial de P. hispidinervum ocasionou nas 24 h de exposição CL50 de 0,42% e CL99 de 0,88%, nas 48 h de exposição CL50 de 0,45% e CL99 de 1,06%. Observou-se o efeito Knock down sobre as larvas de A. cajennense pelo óleo essencial de P. hispidinervum, influenciando significativamente na mortalidade média. No terceiro estudo observou-se a ação letal do extrato bruto etanólico da casca do caule de M. pubescens sobre R. sanguineus, em 48 h a CL50 e CL99 foi de 0,15% e 0,99%, respectivamente. Os óleos essenciais e extrato estudados demonstraram como método alternativo para a prospecção de acaricidas vegetais, de menor impacto ambiental, a serem utilizados como nova estratégia para controle de R. sanguineus e A. cajennense.

The botanical acaricides are natural products derived from plant secondary metabolism. This metabolism produces a large variety of compounds with acaricidal action that can be exploited through the use of essential oils or as a template for synthesis of synthetic acaricides. The need for safer methods, less harmful to humans and the environment, has stimulated the search for new pesticides from plant products. Thus, the aim of this study was to i) select medicinal and aromatic plants with biological activity on the tick Rhipicephalus microplus and Amblyomma cajennense ii) test the sublethal effects of essential oil of Chrysopogon zizanioides (Poaceae) value of high acidity and acid value low on the stages of egg, larva and adult of A. cajennense and R. microplus iii) test the lethal effects of essential oils of C. zizanioides high acid value and amount of low acidity on larvae of A. cajennense and R. microplus iv) test the sublethal effects of essential oils from Pogostemon cablin (Lamiaceae), Croton sonderianus (Euphorbiaceae), Pelargonium graveolens (Geraniaceae) and Zingiber officinale (Zingiberaceae), on the stages of egg, larva and adult of R. microplus v) test the lethal effects of essential oils of P. cablin; C. sonderianus; P. graveolens on larvae of R. microplus iv) From the oil more toxic for the tick R. microplus, producing a formulation and testing the lethal and sublethal effects of this emulsion in ticks R. microplus. Essential oils were purchased through the company Raros, only the Z. officinale obtained by hydrodistillation of dry biomass in a Clevenger type apparatus at the Federal University of Sergipe. These oils were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The study was conducted at the Federal University of Sergipe, Saint Kitts-SE, Brazil. The essential oils were emulsified with Triton X-100 as surfactant agent, in the bioassay with adults and diluted in acetone to bioassay with larvae mortality. In bioassay with adult females were immersed in a final solution (oil with Triton X-100) for 2 minutes, oviposition calculated after 14 days. For the bioassay the larvae a solution (oil in acetone) was applied on filter paper envelopes closed with clips type |bulldog| in which these larvae were maintained for 48 hours. The formulation in both bioassays was diluted with water The paper was divided into three items. In the first article was made a literature review on the use of essential oils of medicinal and aromatic plants in controlling R.microplus, in the second it was demonstrated that the essential oils of C. zizanioides acid value and high value low acidity showed activity ticks on species A. cajannense and R. microplus and third article was observed that the essential oil P. cablin (Lamiaceae) and formulation made from this oil exhibit activity ticks on the tick R. microplus. / Os carrapaticidas botânicos são produtos naturais derivados do metabolismo secundário das plantas. Esse metabolismo produz uma grande diversidade de compostos com ação acaricida que podem ser explorados através do uso de óleos essenciais ou como modelo para síntese de carrapaticidas sintéticos. A necessidade de métodos mais seguros, menos agressivos ao homem e ao meio ambiente, tem estimulado a busca de novos pesticidas a partir de produtos vegetais. Assim, objetivou-se com este trabalho i) selecionar plantas medicinais e aromáticas com atividade biológica sobre os carrapatos Rhipicephalus microplus e Amblyomma cajennense; ii) testar os efeitos subletais do óleo essencial de Chrysopogon zizanioides (Poaceae) acidez alta e acidez baixa sobre os estádios de ovo, larva e adulto de A. cajennense e R. microplus; iii) testar os efeitos letais dos óleos essenciais de C. Zizanioides acidez alta e acidez baixa sobre larvas de A. cajennense e R. microplus; iv)testar os efeitos subletais dos óleos essenciais de Pogostemon cablin (Lamiaceae), Croton sonderianus (Euphorbiaceae), Pelargonium graveolens (Geraniaceae) e Zingiber officinale (Zingiberaceae), sobre os estádios de ovo, larva e adulto de R. microplus; v) testar os efeitos letais dos óleos essenciais de P. cablin; C. sonderianus; P. graveolens sobre larvas de R. microplus; iv) A partir do óleo mais tóxico para o carrapato R. microplus, produzir uma formulação e testar os efeitos subletais e letais dessa emulsão nos carrapatos R. microplus. Os óleos essenciais foram adquiridos através da empresa Raros, sendo apenas o Z. officinale obtido por hidrodestilação da biomassa seca em um aparelho do tipo Clevenger na Universidade Federal de Sergipe. Estes óleos foram analisados por cromatografia gasosa acoplada à espectrometria de massa (GC-MS). O estudo foi realizado na Universidade Federal de Sergipe, São Cristóvão-SE, Brasil. Os óleos essenciais foram emulsionados com Triton X-100, como agente surfactante, no bioensaio com os adultos e diluídos em acetona para o bioensaio de mortalidade com as larvas. No bioensaio com os adultos as fêmeas foram imersas em uma solução final (óleo com Triton X-100) por 2 minutos, calculado a oviposição depois de 14 dias. Para o bioensaio com as larvas uma solução (óleo com acetona) foi aplicada em envelopes de papel filtro fechados com clipes tipo buldogue , no qual estas larvas permaneceram por 48 horas. A formulação nos dois bioensaios foi diluída em água A dissertação foi dividida em dois artigos. No primeiro artigo foi demonstrado que os óleos essenciais de C. zizanioides acidez alta e acidez baixa apresentaram atividade carrapaticida sobre as espécies A. cajannense e R. microplus e no segundo artigo foi observado que O óleo essencial de P. cablin (Lamiaceae) e a formulação feita através deste óleo apresentam atividade carrapaticida sobre o carrapato R. microplus.

The field of vector-borne disease research uses multidisciplinary approaches to help understand complicated interactions. This dissertation, covers three different aspects of tick-borne disease research which all focus on exploring tick-borne diseases in the non-endemic areas of Denton, County Texas and the state of Texas with a focus on Rickettsia spp. These aspects include tick sampling, testing ticks for the presence of Rickettsia spp., and creating species distribution maps of the Rickettsia spp. Rickettsia amblyommatis and tick species Amblyomma americanum.