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Rhipicephalus (Boophilus) microplus é o parasito de maior importância econômica para a produção bovina. Há suspeita de resistência disseminada a ivermectina (IVM), droga amplamente utilizada para seu controle e seu diagnóstico preciso se faz necessário. Neste trabalho foram padronizados testes diagnósticos in vitro que, ao serem aplicados a campo no Brasil, diagnosticaram a resistência em 18 de 30 populações testadas. A resistência in vitro foi confirmada por teste in vivo. Testes com sinergistas sobre cepa resistente isolada indicaram que a destoxificação enzimática tem papel secundário na resistência. Não foram encontradas mutações associadas à resistência no trecho analisado do gene GluCl. Informações obtidas sobre evolução da resistência a campo e em laboratório poderão ser úteis para o uso de IVM no controle de R. (B.) microplus. Os estudos conduzidos sobre mecanismos de resistência podem servir para o desenvolvimento de marcadores moleculares diagnósticos de resistência a IVM. / Rhipicephalus (Boophilus) microplus is the most economically important parasite for cattle production. There is suspicion of widespread resistance to ivermectin (IVM), a drug widely used for their control and being necessary its accurate diagnosis. In this study were standardized in vitro diagnostic tests that, when applied to the field in Brazil, diagnosed resistance in 18 of 30 populations tested. The in vitro resistance was confirmed by a field trial. Tests with synergists on an isolated resistant strain indicated that enzyme detoxification has a secondary role in resistance. There were no mutations associated with resistance in the analyzed fragment of the gene GluCl. Information obtained about the evolution of resistance in field and laboratory may be useful for the use of IVM in the control of R. (B.) microplus. The conducted studies on resistance mechanisms may serve for the development of diagnostic molecular markers of resistance to IVM.

Rhipicephalus (Boophilus) microplus é o parasito de maior importância econômica para a produção bovina. Há suspeita de resistência disseminada a ivermectina (IVM), droga amplamente utilizada para seu controle e seu diagnóstico preciso se faz necessário. Neste trabalho foram padronizados testes diagnósticos in vitro que, ao serem aplicados a campo no Brasil, diagnosticaram a resistência em 18 de 30 populações testadas. A resistência in vitro foi confirmada por teste in vivo. Testes com sinergistas sobre cepa resistente isolada indicaram que a destoxificação enzimática tem papel secundário na resistência. Não foram encontradas mutações associadas à resistência no trecho analisado do gene GluCl. Informações obtidas sobre evolução da resistência a campo e em laboratório poderão ser úteis para o uso de IVM no controle de R. (B.) microplus. Os estudos conduzidos sobre mecanismos de resistência podem servir para o desenvolvimento de marcadores moleculares diagnósticos de resistência a IVM. / Rhipicephalus (Boophilus) microplus is the most economically important parasite for cattle production. There is suspicion of widespread resistance to ivermectin (IVM), a drug widely used for their control and being necessary its accurate diagnosis. In this study were standardized in vitro diagnostic tests that, when applied to the field in Brazil, diagnosed resistance in 18 of 30 populations tested. The in vitro resistance was confirmed by a field trial. Tests with synergists on an isolated resistant strain indicated that enzyme detoxification has a secondary role in resistance. There were no mutations associated with resistance in the analyzed fragment of the gene GluCl. Information obtained about the evolution of resistance in field and laboratory may be useful for the use of IVM in the control of R. (B.) microplus. The conducted studies on resistance mechanisms may serve for the development of diagnostic molecular markers of resistance to IVM.

Hemoparasitos do filo Apicomplexa merecem destaque devido ao impacto que podem ter na conservação da biodiversidade dos mamíferos. O presente estudo objetivou avaliar a ocorrência de agentes Piroplasmida (Cytauxzoon, Theileria e Babesia) e Hepatozoon spp., utilizando o Exame Microscópico Convencional (EMC) e a Reação em Cadeia da Polimerase (PCR), e identificar os carrapatos presentes em mamíferos silvestres destinados ao LAPAS-UFU, CETAS-GO/IBAMA e CETAS-BH/IBAMA. Obteve-se 152 amostras de sangue total e realizou-se a PCR para Hepatozoon spp., com a utilização dos primers HepF300/Hep900, Hep2F/Hep2R e HAM-1/HPFR2, e para a ordem Piroplasmida, realizou-se a PCR com auxílio dos primers BAB- 33-47/ BAB432-439, PIRO 1F/PIRO 5R. Com punção de sangue periférico, confeccionou-se 352 extensões de 123 animais. Pelo EMC, não foram observados gamontes de Hepatozoon spp., mas pela PCR obteve-se 5,2% de positividade (oito positivos). Foram obtidos quatro novos haplótipos de Hepatozoon canis e Hepatozoon felis nos mamíferos de espécies lobo-guará (Chrysocyon brachyurus), raposa-do-campo (Lycalopex vetulus), irara (Eira barbara) e onça-parda (Puma concolor). Para os piroplasmas, pelo EMC e PCR, obteve-se 34,9% (43 animais positivos) e 26,3% (40 animais positivos), respectivamente. Foram obtidos três novos haplótipos de espécies de piroplasmas, sendo sequências similares à Theileria cervi em veado-catingueiro, Theileria equi em anta e Cytauxzoon felis em jaguatirica. Foram identificadas 432 espécimes, de 30 animais. Os carrapatos identificados foram: Amblyomma nodosum, A. parvum, A. ovale, A. sculptum, A. longirostre, A. dubidatum, Rhipicephalus microplus e R. sanguineus. Além disso, outros hemoparasitos foram observados em microscopia óptica, como Ehrlichia spp. em 23 animais (18,6%) e microfilárias em dois indivíduos de espécie Coendou prehensilis (ouriço-cacheiro). O conjunto de informações trazidas por este trabalho comprova a abundância de hemoparasitos que mamíferos brasileiros podem albergar. Além disso, algumas espécies de carrapatos identificados foram determinantes para inferir possíveis modos de transmissão de hemoparasitos observados nos animais. Sobre o resultado obtido pelo uso das técnicas de diagnóstico, a PCR, aliada ao sequenciamento, mostrou-se mais precisa que o EMC para identificação de espécies de hemoparasitos-alvo deste trabalho. / Haemoparasites belonging to filum Apicomplexa deserve attention because can affect the conservation of mammals’s biodiversity. This work aimed to avalue the occurencce of Piroplasmida agents (Cytauxzoon, Theileria e Babesia) e Hepatozoon spp. using Convencional Microscopic Exam (CME) and Polymerase Chain Reaction (PCR) and indetify ticks on wild mammals belonging to LAPAS-UFU, CETAS-GO/IBAMA e CETAS-BH/IBAMA. On total, this work obtained 152 total blood samples that were submited to PCR for Hepatozoon spp. with primers HepF300/Hep900, Hep2F/Hep2R e HAM-1/HPFR2, and for Piroplasmida agents, PCR was done using primers BAB- 33-47/ BAB432-439, PIRO 1F/PIRO 5R. To exam slides on optic microscope, was used peripheral samples of 123 mammals. There wasn’t observed gamonts of Hepatozoon spp. on blood slides, but on PCR was observed prevalence of 5,2% (eight positive mammals). From these, was obtained four new haplotypes of Hepatozoon spp. like similar sequence of Hepatozoon canis in maned-wolf (Chrysocyon brachyurus) and hoary fox (Lycalopex vetulus) and similar sequence of Hepatozoon felis in tayra (Eira barbara) and puma (Puma concolor). For Piroplasmida agents, the CME and PCR results were 34,9% (43 positive mammlas) and 26,3% (40 positive mammals), respectively. There was obtained three new haplotypes of Piroplasmida agents, being similar sequences of Theileria cervi in brown brocket deer (Mazama gouazoubira), similar sequence of Theileria equi in brazilian tapir (Tapirus terrestris) and similar sequence of Cytauxzoon felis in ocelot (Leopardus pardalis). There was identified 432 specimnes of ticks on 30 mammals. The species were Amblyomma nodosum, A. parvum, A. ovale, A. sculptum, A. longirostre, A. dubidatum, Rhipicephalus microplus e R. sanguineus. Besides this results, other haemoparasites were observed on optic microscope, like Ehrlichia spp. in 23 mammals (18,6%) and microfilaria in two mammals of the species Coendou prehensilis (brazilian porcupine). The information gathered by this work confirms the abundance of haemoparasites that the Brazilian mammals can harbor. In addition, some species of ticks identified were determinant to infer possible ways of transmitting hemoparasites identified in mammals. The result obtained by the use of molecular diagnostic techniques (PCR and sequencement) was more accurate than the CME for identification of hemoparasites on wild mammals of this work. / Dissertação (Mestrado)

Made available in DSpace on 2014-07-29T15:13:41Z (GMT). No. of bitstreams: 1 dissertacaoCarlaLouly.pdf: 1077366 bytes, checksum: b65a73f51a856c3912b92c4b294caf0e (MD5) Previous issue date: 2008-08-15 / This study aimed to identify 2,6-dichlorophenol (2,6-DCP) in Amblyomma cajennense and to evaluate its role in A. cajennense and Rhipicephalus sanguineus courtship. Hexanic extract from attractive females was purified by solid phase extraction and the phenol was identified by the single ion monitoring method using GC/MS. In an olfactometer, the responses of A. cajennense and R. sanguineus males to females, control rubber septa or rubber septa impregnated with 2,6-DCP at 50, 500, and 5000 ng, respectively, were studied. 2,6-DCP was identified in A. cajennense extract and the males oriented themselves toward the concentration of 500 ng. These septa and the females were recognized as copula partners. The septa treated with 2,6-DCP did not attract and were not even recognized by the R. sanguineus males, whereas the females were recognized. Due to the presence of 2,6-DCP in A. cajennense and the results of biological bioassays, it was concluded that this compound acts as an attractant and mounting sex pheromone in this tick, but it does not play any role in R. sanguineus courtship. / Este estudo teve por objetivo identificar o 2.6-dichlorophenol (2,6-DCP)em Amblyomma cajennense de e avaliar seu papel na cópula de A. cajennense e de Rhipicephalus sanguineus. O extrato hexânico de fêmeas atrativas purificado pela extração da fase contínua e o fenol foi identificado pelo método da monitoração do íon usando o GC/MS. Em um olfatômetro, foram estudadas as respostas de machos de A. cajennense e de R. sanguineus às fêmeas, a septos de borracha ou a septos de borracha impregnados com o 2,6-DCP a 50ng, 500ng, e 5000ng. No extrato de fêmeas de A. cajennense 2,6-DCP foi identificado, os machos orientaram-se para a concentração de 500ng, e estes septos e as fêmeas foram reconhecidos como parceiros para a cópula. Os septos tratados com o 2,6-DCP não atraíram e nem foram reconhecidos pelos machos de R. sanguineus. Devido à presença de 2,6- DCP na espécie A. cajennense e aos resultados dos ensaios biológicos, concluiu-se que este composto atua como um feromônio sexual de atração e de monta nesta espécie, mas não desempenha nenhum papel na cópula do R. sanguineus .

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-25T12:47:20Z No. of bitstreams: 2 Tese - Cíntia das Chagas Bernardo - 2016.pdf: 2168975 bytes, checksum: f20144021bf112df62693342cfba7dae (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-25T12:47:45Z (GMT) No. of bitstreams: 2 Tese - Cíntia das Chagas Bernardo - 2016.pdf: 2168975 bytes, checksum: f20144021bf112df62693342cfba7dae (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-25T12:47:45Z (GMT). No. of bitstreams: 2 Tese - Cíntia das Chagas Bernardo - 2016.pdf: 2168975 bytes, checksum: f20144021bf112df62693342cfba7dae (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-07-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The current study compared the virulence of conidia and blastospores of Metarhizium anisopliae s.l. (IP 363), Metarhizium robertsii (IP 146) and Beauveria bassiana s.l. (IP 361 and GC 307) against Rhipicephalus microplus, and the tolerance to heat and UV-B radiation; in addition, it evaluated the development of conidia and blastospores of the isolates IP 146 and IP 361 on the tick cuticle by scanning electron microscopy (SEM). Larvae and engorged females of R. microplus were treated (larvae: 106, 107 or 108 propagules/mL, females: 107 propagules/mL) by immersion in conidia or blastospores suspensions of tested isolates. The higher percentage of larval mortality was obtained in the group treated with conidia of IP 361, which had lower LC50. In bioassays with engorged females, IP 146 and IP 361 blastospores, provided tick percent control superior to 90%, while conidia of the same isolates, promoted 70.97% and 63.29% of tick control, respectively. Ticks were treated topically with 50 μL of fungal suspension (107 propagules/mL) and incubated at different times from 0 to 96 hours to analyze its development on the engorged females cuticle; after each incubation time, the females were fixed and analyzed by SEM. Blastospores of both isolates have started development 4 hours after treatment, demonstrating rapid development and suggesting penetration by the tick natural openings; at 4 hours incubation, indicative of penetration of IP 361 blastospores through the cuticle was observed, but no signs of penetration was observed with IP 146 blastospores at any time evaluated. Furthermore, fungal suspensions (103 propagules/mL) were exposed to heat (45 °C) for several time periods, then inoculated in Petri plates with BDAY medium plus chloramphenicol (0.055% v/v), and incubated for 7 days at 27 °C and RH ≥ 80%. ARSEF 324 conidia (79.1%) were more tolerant to heat than conidia of IP 363 (55.5%), IP 146 (1.5%), GC 307 (0%), and IP 361 (0% ) at 2 hours exposure, as well as blastospores after 60 minutes exposure, demonstrating mean percent CFU of 100%, 12.3%, 30.7%, 55% and 0%, respectively. Fungal suspensions (103 propagules/mL) were also inoculated on BDAY in Petri plates, and exposed to UV-B radiation; after treatment, plates were incubated for 7 days at 27 °C and RH ≥ 80%. No difference in mean relative percent CFU between conidia and blastospores was observed. Suitable adjuvants which aim at protecting fungal propagules against stressful abiotic factors are required for conidia and blastospores; however, the selection of isolates with marked natural tolerance to heat and UV-B radiation may increase performance of bioproducts. Accordingly, it is suggested that blastospores are promising fungal propagules for biological control of ticks, since they were virulent against R. microplus; in addition, the rapid development of blastospores on the tick cuticle indicates they may be exposed shortly to harmful environmental abiotic factors. / O presente estudo comparou conídios e blastosporos de Metarhizium anisopliae s.l. (IP 363), Metarhizium robertsii (IP 146) e Beauveria bassiana s.l. (IP 361 e CG 307) quanto a virulência para Rhipicephalus microplus, e quanto a tolerância ao calor e a radiação UV-B; foi avaliado ainda o desenvolvimento de conídios e blastosporos dos isolados IP 146 e IP 361 na cutícula de carrapatos por meio da microscopia eletrônica de varredura (MEV). Larvas e fêmeas ingurgitadas de R. microplus foram tratadas (larvas: 106, 107 ou 108 propágulos/mL; fêmeas: 107 propágulos/mL) por imersão, com conídios e blastosporos dos isolados avaliados. Maior percentual de mortalidade foi obtido nos grupos de larvas tratadas com conídios de IP 361, o qual obteve menor CL50. No bioensaio com fêmeas, blastosporos de IP 146 e IP 361 proporcionaram percentual de controle superior a 90%, enquanto que conídios dos mesmos isolados promoveram mortalidade de 70,97% e 63,29%, respectivamente. Para análise do desenvolvimento dos propágulos na cutícula de fêmeas ingurgitadas, essas foram tratadas topicamente com 50 µL de suspensão fúngica (107 propágulos/mL), incubadas em diferentes tempos de 0 a 96 horas; após cada tempo de incubação as fêmeas foram processadas e analisadas por MEV. Blastosporos de ambos isolados iniciaram seu desenvolvimento já após 4 horas de tratamento, demonstrando rápido desenvolvimento e sugerindo penetração por aberturas naturais do carrapato; com 4 horas de incubação foi possível ver a penetração de blastosporos de IP 361 através da cutícula, situação não evidenciada pelo isolado IP 146 em nenhum tempo avaliado. Nos testes de tolerância ao calor, o isolado de Metarhizium acridum (ARSEF 324) foi inserido como isolado padrão, por ser conhecida a sua tolerância. Suspensões fúngicas (103 propágulos/mL) foram expostas ao calor (45°C) por diferentes tempos, em seguida inoculadas em placas de Petri com meio BDAY acrescido de cloranfenicol (0,055% v/v) e incubadas por 7 dias a 27°C, e UR ≥ 80%. Conídios de ARSEF 324 (79,1%) demonstraram ser mais tolerantes ao calor do que conídios de IP 363 (55,5%), IP 146 (1,5%), CG 307 (0%) e IP 361 (0%) no tempo de 2 horas de exposição, assim como blastosporos no tempo de 60 minutos, demonstrando percentual relativo médio de 100%, 12,3%, 30,7%, 55% e 0%, respectivamente. Nos testes de exposição à UV-B, suspensões fúngicas (103 propágulos/mL) foram inoculadas em placas de Petri contendo BDAY e expostas a diferentes doses de radiação; após tratamento, as placas foram incubadas por 7 dias a 27°C, e UR ≥ 80%. Não houve diferença do percentual relativo médio de conídios e blastosporos expostos a mesma dose de radiação. Adjuvantes adequados que visem proteger os propágulos fúngicos contra fatores abióticos estressantes são requeridos para formulações de conídios e blastosporos; no entanto, a seleção de isolados naturalmente mais tolerantes ao calor e a radiação UV-B podem favorecer o desenvolvimento de bioprodutos. Nesse sentido, acredita-se que blastosporos sejam promissores para o biocontrole de carrapatos, já que estes se demonstraram virulentos para R. microplus, além de apresentarem rápido desenvolvimento sobre a cutícula desse artrópode, o que pode indicar menor tempo de exposição desses propágulos a fatores abióticos limitantes no ambiente.

Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: In southern Africa, the ticks Amblyomma hebraeum and Hyalomma rufipes are the main vectors of animal Heartwater and human Crimean Congo Haemorragic Fever, respectively. In order to investigate the phylogeographic structure of these ectoparasites, population genetic studies were conducted throughout southern and partly eastern Africa. Knowing the levels of genetic diversities and population connectivities throughout the species’ native ranges, may be useful for implementing control measures (cross country borders for example), evaluate the potential for drug resistance in introduced locations as well as for elucidating its vectorial capacities in the region. Mitochondrial cytochrome oxidase I (COI) and the internal transcriber spacer 2 (ITS-2) sequences were obtained from eleven sampled localities. In general, haplotype networks and molecular diversity values showed significant genetic structure between most of the sampled populations. Fu’s Fs and mismatch distributions suggested recent population expansions following a bottleneck. A Mantel regression analysis also revealed a significant isolation by distance for H. rufipes. Comparing the two species, H. rufipes showed much stronger signals of geographic genetic population structure in relation to A. hebraeum. A single taxonomic unit is suggested for A. hebraeum while H. rufipes is characterized by the existence of at least three distinct genetic assemblages that may point to incipient speciation. The difference between the two species may be explained by gene flow restriction within the region, by the number of hosts required to complete the life cycle (2 and 3 hosts, respectively), type of host species (domestic and wild animals; small and big mammals, birds) and its availability, and host species overlap. Also, a geographic break between possible host species during the Pleistocene, domestication of animals and climatic conditions in the region played a role on the genetic structure of H. rufipes. / AFRIKAANSE OPSOMMING: Die suider Afrikaanse bosluise, Amblyomma hebraeum en Hyalomma rufipes is die hoof vektore van Hartwater in diere en Crimean Kongo Haemorargiese koors in mense. Om die filogeografiese struktuur van hierdie ektoparasiete te ondersoek, is bevolking-genetiese studies uitgevoer in suidelike Afrika asook gedeeltelik in oos Afrika. Deur die vlakke van genetiese diversiteit en bevolkingsverbindings regdeur die spesies se natuurlike verspreiding te weet, sal dit dalk moontlik wees om: beheermaatreëls (byvoorbeeld oorgrens) in te stel, die waarskynlikheid van weerstandbiedendheid in nuut losgelate gebiede te verstaan, en meer insigte in die vektoriale kapasiteit te verkry. Mitochondriale sitochroom oksidae (COI) en die interne transkriberende spasieerder 2 (ITS- 2) basisnukleotiedopeenvolgings van elf bevolkings is versamel. Haplotiepe netwerke en molekulêre diversiteitwaardes het in die algemeen, betekenisvolle genetiese verkille tussen meeste van die versamelde bevolkings aangetoon. Fu’s Fs en gemiste-paringverspreidings het voorgestel dat die bevolkings onlangs uitgebrei het nadat hulle 'n bottelnek ondergaan het. 'n Mantel regressie analise het ook betekenisvolle isolasie met afstand aangetoon vir H. rufipes. As die twee spesies vergelyk word het H. rufipes baie sterker seine van genetiese geografiese bevolkingstruktuur gewys as A. hebraeum. 'n Enkele taksonomiese eenheid word voorgestel vir A. hebraeum terwyl H. rufipes gekarakteriseer word deur ten minste drie taksonomiese eenhede. Die verskil tussen die twee spesies kan moontlik verklaar word deur geen-vloeibeperkings in die gebied, die aantal gasheer spesies wat benodig word om die lewenssiklus te voltooi (2 of 3 gashere onderskeidelik), tipe gasheer (domestikeerd- of wildlewend; klein of groot soogdiere, voëls) en hulle beskikbaarheid, en die gasheerspesies se oorvleueling. Dit is ook moontlik dat 'n geografiese breek tussen moontlike gasheerspesies gedurende die Pleistoseen, domestikering van diere en klimaatstoestande in die streek 'n rol kon speel by die genetiese struktuur van H. rufipes. / The NRF and the University of Stellenbosch for funding and bursary

This study examined variation in ectoparasite density and grooming behavior of naturally occurring white-tailed deer (Odocoileus virginianus) in southwest Alabama. Stimulus-driven grooming as well as the intraspecific body size and vigilance principles of programmed grooming were tested. During the rut, males had a higher average tick (Ixodidae) density than females and exhibited complete separation of tick parasitism between non-rutting and rutting periods, supporting the vigilance principle. Stimulus-driven grooming was supported, as both fawns and yearlings had significantly higher fly (Hippoboscidae) and combined fly/tick densities than adults, and fawns oral groomed at a significantly higher rate than adults, even in the absence of allogrooming. Programmed and stimulus-driven grooming of deer examined in this study were not mutually exclusive but ectoparasite dependent.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-03T17:33:38Z No. of bitstreams: 1 2012 - Hermes Ribeiro Luz.pdf: 2629217 bytes, checksum: 8e75ef38df8d873d63a0480f410610a8 (MD5) / Made available in DSpace on 2017-05-03T17:33:38Z (GMT). No. of bitstreams: 1 2012 - Hermes Ribeiro Luz.pdf: 2629217 bytes, checksum: 8e75ef38df8d873d63a0480f410610a8 (MD5) Previous issue date: 2012-02-09 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / This study analyzes the prevalence and mean intensity of infestation of ticks on birds captured in ESEC-Pirapitinga (180 20?S e 450 17?WGr), in Tr?s Marias, Minas Gerais, Brazil. Of a total of 1.295 birds captured, distributed in nine orders, 28 families and 92 species, 165 (12.7%) individuals were parasitized by ticks. Of these 160 (97%) belonged to the order Passeriformes and only 5 (3%) belonged to the grouping of non-passerines. We identified five tick species: Amblyomma longirostre (n = 274) was the most common species followed by Amblyomma parvum (n = 43), Amblyomma nodosum (n = 39), Amblyomma ovale (n = 24) and Rhipicephalus sanguineus (n = 7). The average infestation was 2.7 ticks by bird. Only 16 (10%) birds were infected with more than 5 ticks, while 97 (58.8%), birds were infected with a single tick. Also present in this study, some new records of A. longirostre. A. parvum, A. nodosum, A. ovale and R. sanguineus parasitizing birdscn / No presente estudo analisamos a preval?ncia e intensidade m?dia de infesta??o de carrapatos em aves capturadas na ESEC-Pirapitinga (180 20?S e 450 17?WGr), no munic?pio de Tr?s Marias, Minas Gerais, Brasil. De um total de 1295 aves capturadas, distribu?das em 9 ordens, 28 fam?lias e 92 esp?cies, 165 (12,7%) indiv?duos estavam parasitados por carrapatos. Destes 160 (97%) pertencia a ordem Passeriformes e apenas 5 (3%) pertenciam ao grupamento dos n?o passeriformes. Foram identificadas 5 esp?cies de carrapatos: Amblyomma longirostre (n= 273) foi a esp?cie mais comum seguida por Amblyomma parvum (n=43), Amablyomma nodosum (n=39), Amblyomma ovale (n=24) e Rhipicephalus sanguineus (n=7). A infesta??o m?dia foi de 2,7 carrapatos por ave. Somente 16 (10%) aves estavam infestadas por mais que 5 carrapatos, enquanto que 97(58,8%), aves estavam infestadas por um ?nico carrapato. Tamb?m apresentamos, neste estudo, alguns registros novos de A. longirostre. A. parvum, A. nodosum, A. ovale e R. sanguineus parasitando diferentes esp?cies de aves