Made available in DSpace on 2014-06-11T19:22:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-22Bitstream added on 2014-06-13T19:08:38Z : No. of bitstreams: 1 nunes_et_me_rcla.pdf: 1014029 bytes, checksum: 950755006ea9299ef56aac556c21f073 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As glândulas salivares dos carrapatos são órgãos importantes na transmissão de patógenos a seus hospedeiros, entretanto, o conhecimento das mudanças morfofisiológicas que nelas ocorrem durante o período de alimentação são limitados. Neste trabalho estudou-se as glândulas salivares de fêmeas de carrapatos Rhipicephalus (Boophilus) microplus por meio de técnicas de morfologia, histoquímica e citoquímica de luz e ultra-estrutural em fêmeas em dois diferentes estágios de alimentação (inicial: 24 a 48 horas de infestação, peso inferior a 0,03g e semiingurgitado: 4 a 5 dias de infestação, peso entre 0,13g e 0,25g), de modo a verificar as mudanças que ocorreriam no tecido glandular neste período e identificar quando teria início o processo de degeneração, além de estabelecer que tipo de morte celular estaria envolvida. As glândulas salivares das fêmeas em início de alimentação mostraram suas células fortemente positivas para ATPase e eficientes na exclusão de corante vital, estando portanto, ativas ou apenas em início de degeneração. Os núcleos, de maneira geral, apresentaram-se preservados, sendo assim, descartada a ocorrência de morte celular neste estágio. A localização da fosfatase ácida demonstrou a participação desta enzima na atividade metabólica destes órgãos, regulando o processo secretor e degradando proteínas. Fêmeas no estágio semiingurgitado apresentaram glândulas com características de degeneração, como perda das especializações de membrana, presença de figuras mielínicas, vacúolos autofágicos, lisossomos, além de alterações nucleares como condensação e marginalização cromatínica, formação de blebs e chegando à fragmentação nuclear. À medida que o processo de alimentação avançou, houve aumento da enzima fosfatase ácida, entretanto, os ácinos mantiveram-se fortemente ATPase positivos. / The ticks salivary glands are important organs to the pathogens transmission to their hosts, however, the knowledge regarding the morphophysiological changes which occur in these structures during the feeding period are limited. In this work, the salivary glands of the Rhipicephalus (Boophilus) microplus female ticks were studied, using morphological,histochemical and ultrastructural citochemistry techniques in individuals at two different feeding stages (initial: 24-48 hours of attachment; weigh lower than 0.03g, and semi-engorged : 4-5 days of attachment; weigh around 0.13 and 0.25g ), in attempt to verifying the changes that would occur in the glandular tissue at this feeding period and identifying when the degeneration process would start, besides establishing which cell death type would be involved. The salivary glands from females at beginning of feeding showed their cells strongly positive to ATPase and efficient for the vital stain exclusion, being thus, active or at initial stages of degeneration. The nuclei, in a general way, present themselves preserved, being thus discarded the signs of the apoptosis occurrence in this stage. The acid phosphatase localization demonstrated this enzyme participation in the metabolic activity of these organs, regulating the secretory process and degrading proteins. Females at semi-engorged stage showed glands with degenerative characteristics, as loss of membrane especialization, presence of mielinic figures, autophagic vacuoles, lysosomes, besides nuclear alterations as chromatin condensation and marginalization, blebs formation and nuclear fragmentation. As the feeding process progressed, there was a acid phosphatase enzyme increase, however, the acini maintained strongly ATPase- positive. The results here obtained showed that the R. (B.) microplus salivary glands in females at... (Complete abstract, click electronic access below)

Made available in DSpace on 2014-06-11T19:23:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-30Bitstream added on 2014-06-13T20:10:22Z : No. of bitstreams: 1 sanches_gs_me_rcla.pdf: 728083 bytes, checksum: 12fcc56f356d12f1c615de733e01452c (MD5) / O presente estudo apresenta a descrição da morfologia externa de larvas e a redescrição de ninfas do carrapato Amblyomma brasiliense, utilizando microscopia de luz, lupa estereoscópica e microscopia eletrônica de varredura. As larvas apresentaram a base do capítulo retangular, palpos curtos e idiossoma arredondado, coxa I com dois espinhos, sendo o externo mais longo que o interno e coxas II e III com um espinho, enquanto as ninfas apresentaram a base do capítulo também retangular, com córnua pontiaguda, idiossoma oval, coxa I com dois espinhos evidentes, sendo o externo mais longo que o interno, coxas II e III com um espinho curto em cada uma, e coxa IV, com um espinho muito pequeno e a presença de tubérculos quitinosos na superfície interna da borda posterior dos festões. Além disso, a morfologia do ovário e o processo de dinâmica da vitelogênese dos ovócitos de fêmeas ingurgiradas desta espécie de carrapato também são apresentados. O ovário, classificado como panoístico por não apresentar células foliculares e nutridoras, consiste em estrutura tubular única e contínua com ovócitos de vários tamanhos e diferentes estádios de desenvolvimento, presos a parede epitelial por meio do pedicelo. Tais ovócitos são aqui classificados em cinco estádios de acordo com a aparência do citoplasma, observação da vesícula germinal, aspecto dos grãos de vitelo e deposição do córion. Pela primeira vez foi observado em carrapatos ovócitos com o córion esculturado. / The present study shows the external morphological description of larvae and the redescription of nymphs of Amblyomma brasiliense ticks under light microscope, stereoscopic microscope and scanning electron microscope. Larvae present basis capituli rectangular, short palpi, idiosoma rounded, coxa I with two spurs being the external longer than the internal one and coxae II and III each with one short spur. Nymphs present basis capituli rectangular with a sharp pointed cornua, oval idiosoma with scutum reaching coxa III and coxae I with two evident spurs being the external longer than the internal one; coxae IIIII each with one short spur and coxae IV with a very short spur and chitinous tubercles on internal surface of posterior border of festoons. Furthermore, the ovary morphology and the dynamics of the vitellogenesis process in oocytes of Amblyomma brasiliense engorged females. The ovary is classified as the panoistic type; therefore, it lacks nurse and follicular cells. This organ consists of a single tubular structure, continuous, with oocytes of various sizes and at different developmental stages remain attached to the ovary through a cellular pedicel. The oocytes were classified into five stages described according to cytoplasm appearance, presence of the germ vesicle, yolk granules aspects, and chorion deposition. For the first time was related in ticks oocytes chorium sculptured.

Orientador: Gervásio Henrique Bechara / Coorientador: Gilson Pereira de Oliveira / Banca: Rosimeri de Oliveira Vasconcelos / Banca: Pablo Henrique Nunes / Resumo: A imunização dos hospedeiros contra carrapatos tem sido considerada como uma alternativa promissora. Vacinas contendo o antígeno Bm86 (Gavac®, TickGard®) foram desenvolvidas originalmente para controlar infestações de Rhipicephalus Boophilus microplus. Como recentes estudos filogenéticos mostraram que o gênero Rhipicephalus inclui todas as cinco espécies de Boophilus, o papel protetor do antígeno Bm86 em cães imunizados e desafiados com carrapatos Rhipicephalus sanguineus foi testado previamente neste laboratório. Dando continuidade, o presente estudo teve como objetivo descrever o componente celular inflamatório no local de fixação do carrapato em cães imunizados com o antígeno Bm86 e desafiados com carrapatos adultos R. sanguineus. Para tanto, cães SRD (n=8), foram distribuídos em dois grupos (não vacinado e vacinado) e receberam duas doses de 50 g do antígeno Bm86 (Hebercan®) ou placebo, com 21 dias de intervalo. Cada animal foi desafiado com 55 carrapatos adultos 15 dias após a última dose e biopsias da lesão de fixação dos carrapatos foram coletadas as 48, 96, 144 e 192 horas após sua fixação. Os fragmentos foram então processados histologicamente e as secções coradas com hematoxilina-eosina e Giemsa. Nos animais vacinados predominaram neutrófilos, eosinófilos e mastócitos na 48ª hora PF, enquanto que nos não vacinados houve predomínio de eosinófilos, neutrófilos e linfócitos. Com o decorrer da infestação, observou-se um infiltrado celular mais intenso a partir de 96h PF, atingindo as camadas mais profundas da derme, sendo composto principalmente por neutrófilos e linfócitos nos vacinados, e eosinófilos, linfócitos e neutrófilos nos não vacinados. Concluiu-se que o antígeno Bm86 administrado em cães interfere na resposta inflamatória induzida por R. sanguineus / Abstract: Immunization of hosts against ticks has long been considered as a promising alternative. Vaccines containing the Bm86 antigen (e.g. Gavac®, Heber-Biotec, Cuba) have been developed to control Rhipicephalus Boophilus microplus infestations. As recent molecular phylogeny studies showed that the Rhipicephalus genus includes all five Boophilus species, the protector role of Bm86 antigen in immunized dogs challenged with adult Rhipicephalus sanguineus was investigated first at this lab. This study aimed to evaluate the inflammatory cells at the attachment site of ticks in dogs immunized by the Bm86 antigen against infestations of adults of Rhipicephalus sanguineus ticks. Mongrel dogs (n=8), were divided into two groups (non-vaccinated and vaccinated). It was given twice 50 g of Bm86 antigen (Gavac®, Heber-Biotec, Cuba) or placebo, at 21 days interval. Each animal was challenged with 55 adult ticks 15 days after the last dose. Biopsies of tick feeding lesions taken 48, 96, 144 e 192 hours post-attachment (PA) were processed through routine histology and sections 4μm thickness stained with H.E. and Giemsa for general features and cell counts, respectively. There was an inflamed dermis including an inflammatory cell infiltrate constituted overwhelmingly by neutrophils, eosinophils and mast cells in vaccinated dogs at first and eosinophils, neutrophils and lymphocytes in non-vaccinated hosts. After 96h PA, a dense and diffuse cell infiltrate reached into deep dermis, constituted overwhelmingly by neutrophils and lymphocytes in vaccinated dogs and eosinophils, lymphocytes and neutrophils in non-vaccinated dogs. It's been concluded that antigen Bm86 administered to dogs interferes on the Rhipicephalus sanguineus induced inflammatory cell influx / Mestre

A emergência e reemergência de doenças transmitidas por artrópodes são desafios para as medicina Veterinária e Humana. Cães domésticos estão frequentemente expostos as diferentes espécies de carrapatos, os quais fazem destes animais bons sentinelas para riquetsioses que afetam os humanos. O Estado do Maranhão está localizado na região Nordeste do Brasil, numa área de transição dos biomas Amazônia e Cerrado. Neste contexto, no presente estudo, objetivou-se avaliar infecções por riquétsias em cães e carrapatos. Durante o perído de 2011 a 2013, amostras de sangue foram coletadas aleatoriamente de 1560 cães, sendo de áreas urbanas e rurais de oito municípios: Açailândia, Balsas, Barreirinhas, Caxias, Cururupu, Grajaú, São Bento e São Domingos. As amostras foram testadas pela reação de imunofluorescência indireta para cinco espécies de riquétisas: Rickettsia rickettsii, Rickettsia parkeri, \"Candidatus Rickettsia amblyommii\", Rickettsia rhipicephali e Rickettsia bellii. Os carrapatos foram coletados sobre os cães, identificados morfologicamente e submetidos a pesquisa de riquétsias, quase todos os carrapatos foram submetidos ao teste de hemolinfa e tentativa de isolamento de riquétsia. Do total, 12,6% (196/1560) dos cães foram sororreativos a Rickettsia spp. Noventa e dois soros mostraram títulos para Rickettsia parkeri, \"Candidatus Rickettsia amblyommii\", Rickettsia rhipicephali and Rickettsia bellii pelo menos quatro vezes maior do que aqueles outros antígenos de riquétisa. Desta forma, considera-se que os cães foram infectados por Rickettsia parkeri (1 soro), \"Candidatus Rickettsia amblyommii\" (73 soros), Rickettsia rhipicephali (6 soros) and Rickettsia bellii (12 soros), com títulos variando de 128 a 16.384. Novecentos e cinquenta e nove carrapatos foram coletados sobre os cães, Rhipicephalus sanguineus, Amblyomma cajennense sensu lato, Amblyomma ovale, Amblyomma parvum, Amblyomma oblongoguttatum, Amblyomma rotundatum, Rhipicephalus (Boophilus) microplus, Haemaphysalis juxtakochi e Amblyomma sp. Produtos da reação em cadeia pela polimerase de 17 carrapatos foram sequenciados e mostraram corresponder a \"Candidatus Ricketsia andeanae\", Rickettsia bellii and \"Candidatus Rickettsia amblyommii\". Estes resultados sugerem que estas riquétsias ou uma cepa muito próxima estão infectando cães no Estado do Maranhão, ressaltando o potencial patogênico destas espécies de riquétsias no Nordeste do Brasil. Ao mesmo tempo, diferencia-se do Sudeste do Brasil, onde hospedeiros sentinelas como os cães, tendem a ter maiores títulos para Rickettsia rickettsii ou Rickettsia parkeri, os agentes da febre maculosa no Sudeste do Brasil. / The emergence and reemergence of diseases transmitted by arthropods are challenges for the Veterinary and Human medicine. Domestic dogs are often exposed to different tick species, what makes these animals good sentinels for rickettsial diseases that affect humans. The state of Maranhão is located in the northeastern region of Brazil, in a transition area from Amazon to Savannah biomes. In this context, the present study aimed to evaluate rickettsial infection in dogs from this state. During the period 2011 to 2013 blood samples were randomly collected from 1560 domestic dogs, being from urban and rural areas of eight municipalities of Maranhão: Açailândia, Balsas, Barreirinhas, Caxias, Cururupu, Grajaú, São Bento and São Domingos. Samples were tested by indirect imunofluorescence assay against 5 Rickettsia species: Rickettsia rickettsii, Rickettsia parkeri, \"Candidatus Rickettsia amblyommii\", Rickettsia rhipicephali and Rickettsia bellii. Ticks were collected on dogs to morphological taxonomic identification and to rickettsia research, almost ticks were submitted to hemolymph test and shell vial attempting to isolate rickettsia. Overall, 12.6% (196/1560) of the dogs were seroreactive to Rickettsia spp. Ninety-two sera showed titers to Rickettsia parkeri, \"Candidatus Rickettsia amblyommii\", Rickettsia rhipicephali and Rickettsia bellii at least 4- fold higher than those observed to the other rickettsial antigens. In this way, we considered that these dogs were infected by Rickettsia parkeri (1sera), \"Candidatus Rickettsia amblyommii\" (73 sera), Rickettsia rhipicephali (6 sera) and Rickettsia bellii (12 sera), with titers ranging from 128 to 16,384. Nine hundred and fifty-nine ticks were collected on dogs (Rhipicephalus sanguineus, Amblyomma cajennense sensu lato, Amblyomma ovale, Amblyomma parvum, Amblyomma oblongoguttatum, Amblyomma rotundatum, Rhipicephalus (Boophilus) microplus, Haemaphysalis juxtakochi and Amblyomma sp). Polymerase chain reaction products of at least seventeen of these ticks were sequenced and also showed to correspond to \"Candidatus Ricketsia andeanae\", Rickettsia bellii and \"Candidatus Rickettsia amblyommii\". These results suggest that these ricketsias or close-related strains are infecting dogs in Maranhão state, highlighting the potential pathogenicity of these Rickettsia species in northeastern Brazil. At the same time, it differentiates from southeastern Brazil, where sentinel hosts like dogs tend to have higher titers to Rickettsia rickettsii or Rickettsia parkeri, the agents of spotted fever in southeastern Brazil.

O Parque Nacional Grande Sertão Veredas (PNGSV) é uma das últimas reservas naturais de Cerrado do Brasil, localizada no noroeste de Minas Gerais. O presente estudoenvolveu 24 meses de trabalho de campo, que incluiuoito campanhas ao parque, intervaladas de três meses, com o objetivo de determinar a ocorrência e aspectos ecológicos de carrapatos e riquétsias no meio ambiente, em pequenos mamíferos e aves.No total 8488 carrapatos foram coletados durante as campanhas. Foram coletados nas armadilhas de CO2 3050 carrapatos, sendo 2369 A. sculptum, 337 A. parvum, 233 A. triste, 13 A. dubitatum e 98 Amblyomma spp., enquanto por arraste de flanela 1998 carrapatos foram coletados, sendo 1511 A. sculptum, 77 A. parvum, 83 A. triste, um A. dubitatum e 326 Amblyomma spp. Foram capturados 75 pequenos mamíferos de 16 espécies, 10 pertencem à ordem Didelphimorphia e 65 à ordem Rodentia, 48 (64%) deles estavam parasitados por carrapatos, sendo 208 ninfas (114 A. parvum, 64 A. triste, 23 A. auricularium, quatroA. sculptum, umA. dubitatum, umA. naponense e umAmblyomma spp.) e 1358 larvas (93 Ornithodoros mimon, 17 A. triste, 14 A. parvum, quatroA. auricularium, trêsA. Sculptum, umIxodes spp. e 1226 larvas não identificadas). Foram capturadas 717 aves de88 espécies, destas, 74 (10,3%) estavam parasitadas por 247 espécimes de carrapatos imaturos, sendo seisA. sculptum, 14 A. parvum, 29 A. triste, umA. dubitatum, 66 A. nodosum e 131 Amblyomma spp.Cinco isolados de R. parkeriforam obtidos de 12 A. tristee quatro isolados de R. belliiforam obtidos de oito A. parvum, além de detecção molecular de Candidatus R. andeanae em A. parvum e R. amblyommi em A. sculptum.Nas duas propriedades rurais, de 36 caninos, 20 equinos e 12 bovinos inspecionadosforam coletados 1186 carrapatos, sendo 639 A. sculptum, 58 A. parvum, quatroA. triste, 17 A. tigrinum, um A. ovale, 17 R. sanguineus, 177 R. microplus, 91 D. nitens e 182 do gênero Amblyomma. Foram coletados parasitando 21 humanos um total de 441 carrapatos, entre imaturos e adultos, sendo 333 A. sculptum, 64 A. parvum, trêsA. auricularium, doisR. microplus e umD. nitens. Sorologia foi realizada em 64 amostras, sendo que apenas 20 (31,25%) sororeagiram para algum dos seis antígenos de Rickettsia testados e foi observado títulos quatro vezes maiores para R. parkeri em dois O. delator e doisC. Tener. Os resultados mostram a riqueza de espécie de pequenos mamíferos, aves, carrapatos e riquétsias encontrados na pequena área estudada no parque. Com a sua abertura à visitação turística, deve-se ter em mente não apenas o risco de infestação por carrapatos, mas também a infecção por, pelo menos, quatro espécies de Rickettsia encontradas durante a pesquisa / The Grande Sertão Veredas National Park (GSVNP) is one of the last natural reserves of Cerrado of Brazil, located in the northwest of Minas Gerais. This study involved 24 months of field work, which included eight campaigns at the park with intervals of three months, in order to determine the occurrence and ecological aspects of ticks and riquetsiaon the environment, small mammals and birds. In total 8488 ticks were collected during the campaigns. Through CO2traps 3050ticks were collected, being 2369 A. sculptum, 337 A. parvum, 233 A. triste, 13 A. dubitatum and 98 Amblyomma spp., while by dragging flannel 1998 ticks were collected, being 1511 A. sculptum, 77 A. parvum, 83 A. triste,oneA. dubitatumand 326 Amblyomma spp. 75 small mammals of 16 species were captured, 10 belong to Didelphimorphia order and 65 to the Rodentia order, 48 (64%) of them were parasitized by ticks, being 208 nymphs (114 A. parvum, 64 A. triste, 23 A. auricularium, four A. sculptum,oneA.dubitatum,oneA. naponenseand one Amblyomma spp.) and 1358 larvae (93 Ornithodoros mimon, 17 A. triste, 14 A. parvum, four A. auricularium, three A. sculptum oneIxodes spp. and 1226 larvae unidentified). 717 birds of 88 specieswere captured, of these, 74 (10.3%) were parasitized by 247 specimens of immature ticks, six A. sculptum, 14 A. parvum, 29 A. triste, oneA. dubitatum, 66 A. nodosum and 131 Amblyomma spp. Five isolates of R. parkeri were obtained from 12 A. triste and four isolates of R. bellii were obtained from eight A. parvum. In adition, molecular detection of Candidatus R. andeanae in A. parvum and R. amblyommi in A. sculptum in adults ticks were found. In the two farms, from 36 dogs, 20 horses and 12 bovine inspected 1186 ticks were collected, being 639 A. sculptum, 58 A. parvum, fourA. triste, 17 A. tigrinum, one A. ovale, 17 R. sanguineus, 177 R. microplus, 91 D. nitens and 182 Amblyomma spp. Parasitizing 21 humans a total of 441 immature and adults ticks were collected, being 333 A. sculptum, 64 A. parvum, threeA. auricularium, twoR. microplus and oneD. nitens. Serology was performed on 64 samples, but only 20 (31.25%) sororeacted for some of the six Rickettsia antigens tested. Titers four-fold higher toR. parkeri than against the other antigenswere observed on two O. delator and two C. tener. The results show the richness of ticks species, of small mammalsand birds species and also of Rickettsiaspecies found in the studied area inside the park

Dans ce travail, nous nous sommes intéressés à l’étude des infections à Anaplasmataceae chez les animaux et leurs tiques afin de caractériser au mieux ces infections animales et humaines et décrire de nouvelles espèces. Nous avons tout d’abord proposé un système de diagnostic moléculaire qui couple une qPCR suivie d’amplification et un séquençage ciblant le gène 23S ARNr. Puis, au long de ce travail, nous avons proposé d’autres amorces ciblant d’autres gènes incluant la sous unité ribosomal bêta (rpoB), la protéine du choc thermique (groEl), et le 16S ARNr. Notre objectif a été de sélectionner et d’identifier les différentes espèces impliquées ou non dans des pathologies chez les animaux et mettre en évidence leur vecteur. Au cours de ces travaux, nous avons eu accès à différents prélèvements de sang et des tiques en provenance de diverses régions du monde incluant la France métropolitaine et d’outre-mer, l’Algérie, le Niger, la Côte d’Ivoire, le Sénégal et le Pakistan. Nos investigations ont permis d’identifier différentes espèces d’Anaplasmataceae incluant de potentielles nouvelles espèces. Les prévalences rapportées dans chaque étude démontrent que les animaux sont les réservoirs de ces infections. Les recherches menées sur les tiques ont permis d’identifier de potentiels vecteurs d’Anaplasmataceae dans différentes régions du monde. Les potentielles nouvelles espèces identifiées sont caractérisées en ciblant différents gènes, et les analyses moléculaires démontrent qu’elles sont différentes des autres Anaplasmataceae connues jusqu’à maintenant. Ces différents travaux apportent donc davantage d’informations sur l’épidémiologie des Anaplasmataceae dans le monde. / In this work, we are interested in studying Anaplasmataceae infections in animals and their ticks. Our objective is to describe these infections in animals and to identify new species implicated in different pathology. First, we propose a molecular diagnostic approach that couples a qPCR followed by amplification and sequencing targeting the 23S rRNA gene. Then we propose other primers targeting other genes including the ribosomal subunit beta (rpoB), heat shock protein (groEl), and the 16S rRNA. Our goal was to screen and identify the different species involved, or not involved, in pathologies of animals and identify their vectors. During this work, we had access to different blood samples and ticks from different parts of the world including metropolitan France, France overseas, Algeria, the Republic of Niger, Côte d'Ivoire, Senegal and Pakistan. Our different investigations allowed to identify different species of Anaplasmataceae including potential new species. The prevalence reported in each study demonstrates that animals are the reservoirs of these infections. So, the research conducted on ticks has identified potential vectors of Anaplasmataceae in different regions of the world. Potentially new species were identified are characterized by different targeting genes. These studies provide further information on the epidemiology of Anaplasmataceae in the world.

Tick borne diseases of livestock are among the most important factors which have retarded economic development in many parts of Africa. Modification of the environment due to the expansion of agriculture into previously undeveloped areas, together with the introduction of livestock, has disturbed the natural balance which existed between ticks and indigenous hosts. Many tick species have adapted to domestic stock, and in some instances have spread over large areas which were previously uninfested. A number of tick species which are parasitic on domestic stock, eg. Amblyomma hebraeum Koch, 1844, Boophilus decoloratus (Koch, 1844), Rhipicephalus evertsi Neumann, 1897 and Rhipicephalus appendiculatus Netunann, 1901, are vectors of pathogenic micro-organisms. Unlike indigenous hosts however, domestic stock have no innate immunity to tickborne diseases. Intro., p. 1.

1. In studying the effects of micro-climates on the distribution of larval ticks in the Eastern Cape Province four species were considered, namely, Boophilus decoloratus (Koch), Rhipicephalus evertsi (Neu), Amblyomma hebraeum (Koch) and Ixodes pilosus (Koch). 2. Three types of investigation were made:- i) autumn and spring surveys of the distribution of larval clusters, which were assumed to be close to positions in which egg-masses had been laid. - (Four species); ii) observations on the survival and development of eggs and engorged female ticks in microclimatically distinct field plots. - (Four species); iii) observations on the behaviour of the larvae and of the engorged female ticks. - (B. decoloratus). 3. The survey and plot data suggest that in autumn larval clusters of I. pilosus were to be found only in well-shaded situations because more exposed places were micro-climatically unfavourable to the survival of earlier stages. 4. The surveys show that in spring 1957 larval clusters of I. pilosus were to be found in unshaded, as well as in shaded, situations. 5. The survey and plot data indicate that the winter of 1957 was not favourable to the development of larvae of B. decoloratus, and that in spring new larval clusters may be expected to appear first in the warmest situations and later in the generally cooler places. 6. The plot data show that during hot and dry periods exposed situations were unfavourable to tho engorged females and eggs of all four species considered, but that during such periods these stages could sometimes survive in well-shaded places. 7. The survey and plot data show that in autumn and in spring larval clusters of B. decoloratus and R. evertsi may be present in unshaded situations. 8. The plot investigations provide little information about the distribution of larval clusters of A. hebraeum, but the survey data suggest that it is not remarkably different from that of B. decaloratus and R. evertsi. 9. There is a discrepancy in the survey and plot data: the surveys show that larval clusters of R. evertsi, and B. decoloratus were rare or absent from well-shaded situations, whereas tho plot data suggest such situations were micro-climatically favourable to larval developmcnt during the months preceding Autumn. 10. The observations on the behaviour of larvae and engorged females of B. decoloratus provide information which suggests that the behaviour of those stages may account for the rarity of larval clusters in well-shaded places. 11. The relative density of larval clusters of B. decoloratus is evidently also affected by factors other than micro-climate . The dropping- off behaviour of engorged female ticks appears to be possibly important in this.

Ticks are blood feeding ectoparasites that ingest large volumes of vertebrate blood. They are the most important arthropods that are capable of transmitting pathogens which cause disease in humans and domestic animals. Ticks are exposed to various microorganisms during feeding as well as in their habitat. They therefore must have a very good immune system to recognize and destroy these microorganisms. In the present study a micro-broth dilution assay was used to determine whether antifungal activity was present in different tick tissue extracts with or without challenge. The midguts gave the highest inhibition of yeast growth, followed by the salivary glands and then the hemolymph. This was seen with unchallenged tick tissue extracts, as well as tissue extracts collected after yeast challenge (2 hours). Thus all of the tick tissue extracts that was analyzed in this study had antifungal activity. Proteomics was used to determine whether proteins were differentially expressed in the hemolymph plasma, after a fungal challenge. 2DE was used since proteins are not only separated by molecular mass, but also by their charge. The proteins that were separated on the 2D-gels ranged between 17.5-76 kDa and not all proteins present on the 1D-gels (14-97 kDa) could be seen on the 2D-gels. Ticks were challenged for 2 hours to define the proteins that play a role in the short term innate immune response during a fungal infection. Various proteins were differentially expressed in the hemolymph samples that were collected 2 hours after ticks were injected with saline, â-1,3-glucan or yeast (or 72 hours). Injury and fungal challenge play a role in producing proteins that might play a role in the fungal response of the tick. Five spots that were statistically significant in the hemolymph collected 2 hours after ticks were injected with yeast cells were analyzed with MS/MS. No matches were found with MASCOT database searching or with EST searching. This can be due to the limited information that is available on the soft ticks, as only hard tick ESTs heve been published. It was also attempted to identify hemolymph proteins that might play a role in the recognition of fungi. Hemolymph was incubated with live Candida albicans cells and eluted with buffer. Three protein bands (97, 88 and 26 kDa) were found to be present whether ticks were challenged or unchallenged. These proteins were subjected to MS/MS analysis and database searching was performed revealing no matches to other known proteins. The antifungal response was found to be present in the soft tick O. savignyi and might play a vital function in the innate immune response during a fungal infection. These proteins may serve as lead molecules that could be used in the development of novel antifungal drugs, as well as in vaccine development. Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Biochemistry / unrestricted

O Parque Nacional Grande Sertão Veredas (PNGSV) é uma das últimas reservas naturais de Cerrado do Brasil, localizada no noroeste de Minas Gerais. O presente estudoenvolveu 24 meses de trabalho de campo, que incluiuoito campanhas ao parque, intervaladas de três meses, com o objetivo de determinar a ocorrência e aspectos ecológicos de carrapatos e riquétsias no meio ambiente, em pequenos mamíferos e aves.No total 8488 carrapatos foram coletados durante as campanhas. Foram coletados nas armadilhas de CO2 3050 carrapatos, sendo 2369 A. sculptum, 337 A. parvum, 233 A. triste, 13 A. dubitatum e 98 Amblyomma spp., enquanto por arraste de flanela 1998 carrapatos foram coletados, sendo 1511 A. sculptum, 77 A. parvum, 83 A. triste, um A. dubitatum e 326 Amblyomma spp. Foram capturados 75 pequenos mamíferos de 16 espécies, 10 pertencem à ordem Didelphimorphia e 65 à ordem Rodentia, 48 (64%) deles estavam parasitados por carrapatos, sendo 208 ninfas (114 A. parvum, 64 A. triste, 23 A. auricularium, quatroA. sculptum, umA. dubitatum, umA. naponense e umAmblyomma spp.) e 1358 larvas (93 Ornithodoros mimon, 17 A. triste, 14 A. parvum, quatroA. auricularium, trêsA. Sculptum, umIxodes spp. e 1226 larvas não identificadas). Foram capturadas 717 aves de88 espécies, destas, 74 (10,3%) estavam parasitadas por 247 espécimes de carrapatos imaturos, sendo seisA. sculptum, 14 A. parvum, 29 A. triste, umA. dubitatum, 66 A. nodosum e 131 Amblyomma spp.Cinco isolados de R. parkeriforam obtidos de 12 A. tristee quatro isolados de R. belliiforam obtidos de oito A. parvum, além de detecção molecular de Candidatus R. andeanae em A. parvum e R. amblyommi em A. sculptum.Nas duas propriedades rurais, de 36 caninos, 20 equinos e 12 bovinos inspecionadosforam coletados 1186 carrapatos, sendo 639 A. sculptum, 58 A. parvum, quatroA. triste, 17 A. tigrinum, um A. ovale, 17 R. sanguineus, 177 R. microplus, 91 D. nitens e 182 do gênero Amblyomma. Foram coletados parasitando 21 humanos um total de 441 carrapatos, entre imaturos e adultos, sendo 333 A. sculptum, 64 A. parvum, trêsA. auricularium, doisR. microplus e umD. nitens. Sorologia foi realizada em 64 amostras, sendo que apenas 20 (31,25%) sororeagiram para algum dos seis antígenos de Rickettsia testados e foi observado títulos quatro vezes maiores para R. parkeri em dois O. delator e doisC. Tener. Os resultados mostram a riqueza de espécie de pequenos mamíferos, aves, carrapatos e riquétsias encontrados na pequena área estudada no parque. Com a sua abertura à visitação turística, deve-se ter em mente não apenas o risco de infestação por carrapatos, mas também a infecção por, pelo menos, quatro espécies de Rickettsia encontradas durante a pesquisa / The Grande Sertão Veredas National Park (GSVNP) is one of the last natural reserves of Cerrado of Brazil, located in the northwest of Minas Gerais. This study involved 24 months of field work, which included eight campaigns at the park with intervals of three months, in order to determine the occurrence and ecological aspects of ticks and riquetsiaon the environment, small mammals and birds. In total 8488 ticks were collected during the campaigns. Through CO2traps 3050ticks were collected, being 2369 A. sculptum, 337 A. parvum, 233 A. triste, 13 A. dubitatum and 98 Amblyomma spp., while by dragging flannel 1998 ticks were collected, being 1511 A. sculptum, 77 A. parvum, 83 A. triste,oneA. dubitatumand 326 Amblyomma spp. 75 small mammals of 16 species were captured, 10 belong to Didelphimorphia order and 65 to the Rodentia order, 48 (64%) of them were parasitized by ticks, being 208 nymphs (114 A. parvum, 64 A. triste, 23 A. auricularium, four A. sculptum,oneA.dubitatum,oneA. naponenseand one Amblyomma spp.) and 1358 larvae (93 Ornithodoros mimon, 17 A. triste, 14 A. parvum, four A. auricularium, three A. sculptum oneIxodes spp. and 1226 larvae unidentified). 717 birds of 88 specieswere captured, of these, 74 (10.3%) were parasitized by 247 specimens of immature ticks, six A. sculptum, 14 A. parvum, 29 A. triste, oneA. dubitatum, 66 A. nodosum and 131 Amblyomma spp. Five isolates of R. parkeri were obtained from 12 A. triste and four isolates of R. bellii were obtained from eight A. parvum. In adition, molecular detection of Candidatus R. andeanae in A. parvum and R. amblyommi in A. sculptum in adults ticks were found. In the two farms, from 36 dogs, 20 horses and 12 bovine inspected 1186 ticks were collected, being 639 A. sculptum, 58 A. parvum, fourA. triste, 17 A. tigrinum, one A. ovale, 17 R. sanguineus, 177 R. microplus, 91 D. nitens and 182 Amblyomma spp. Parasitizing 21 humans a total of 441 immature and adults ticks were collected, being 333 A. sculptum, 64 A. parvum, threeA. auricularium, twoR. microplus and oneD. nitens. Serology was performed on 64 samples, but only 20 (31.25%) sororeacted for some of the six Rickettsia antigens tested. Titers four-fold higher toR. parkeri than against the other antigenswere observed on two O. delator and two C. tener. The results show the richness of ticks species, of small mammalsand birds species and also of Rickettsiaspecies found in the studied area inside the park