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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Spatial and Temporal Survey of Feral Pig Ectoparasites in Three Texas Wildlife Districts

Schuster, Anthony 2011 December 1900 (has links)
Feral pigs, European wild boars and their crosses are ubiquitous and found in all ecological zones from Florida to California. These introduced animals are recorded in 39 US states and four Canadian provinces. Texas currently has an estimated population of 1-4 million pigs with the potential to exceed 4 million based on suitable habitat estimates. Feral pigs can modify local flora and fauna and cause significant physical damage with their rooting activities. They can also reintroduce parasites and pathogens to previously parasite and pathogen free herds of domestic cattle, horses, sheep, and goats. The two overarching objectives of this research were to determine what role feral pigs have in the maintenance and possible distribution of fleas, lice, and ticks common to the three wildlife districts; and if they serve as bridging hosts for the same (or other) arthropods and their natural hosts. The supporting objectives were to establish host records of fleas, lice, and ticks parasitizing feral pigs; determine species assemblies within each of the three wildlife districts; and to compare species assemblies among the wildlife districts. Feral pigs (564) were taken from June 2008 to March 2011 using box, corral, and panel traps in three wildlife districts. Two hundred fifty six fleas, Pulex porcinus (Jordan and Rothschild), were collected from all gender and age classes of feral pigs at the South Texas Plains wildlife district. No fleas were collected at either the Hill Country or Post Oak Savannah wildlife districts. This is the first report of these fleas on feral pigs. Lice and ticks were collected from all gender and age classes of feral pigs from all sample sites. Only hog lice, Haematopinus suis, were collected at all three sample sites. Seven species of ticks were collected from the three sites: Amblyomma americanum, A. cajennense, A. maculatum, Dermacentor albipictus, D. halli, D. variabilis, and Ixodes scapularis. Amblyomma cajennense was collected only at the South Texas Plains sample site; A. americanum and I. scapularis were collected only at the Hill Country and Post Oak sample sites. This study reports that feral pigs are serving as hosts for one species of flea, one species of lice and seven species of ticks common to Texas.
162

Detection and quantification of Borrelia lonestari and a rickettsial endosymbiont in Amblyomma americanum ticks from southern Indiana using real-time PCR

Sullivan, Bridget E. January 2005 (has links)
Amblyomma americanum, the lone star tick, is an indigenous tick species in southern Indiana that harbors a diverse group of pathogenic and nonpathogenic microorganisms, including Borrelia lonestari, the putative agent for the southern tick associated rash illness (START) and a spotted fever group rickettsial endosymbiont. The purpose of this study was to implement the real-time polymerase chain reaction (real-time PCR) as a molecular technique to examine the microbial diversity in A. americanum ticks by estimating abundances of different microorgansisms. A SYBR Green real-time PCR assay was designed to detect and quantify B. lonestari in A. americanum ticks, and a previously published TaqMan real-time PCR assay, designed to detect (not quantify) Rickettsia species in ticks, was validated for the detection and quantification of the spotted fever group rickettsial endosymbiont in A. americanum ticks. Many pitfalls associated with real-time PCR were experienced in this study, such as difficulties in assay design and problems with contamination, and appropriate modifications are recommended to laboratories routinely performing real-time PCR. / Department of Biology
163

Genetic variants of Ehrlichia chaffeensis in southern Indiana

Seddighzadeh, Ali January 2003 (has links)
Human monocytotropic ehrlichiosis (HME) is a tick-borne infectious disease caused by the bacterium Ehrlichia chaffeensis and transmitted by the lone star tick, Amblyomma americanum. The disease was recognized in Indiana for the first time in 1994. Since 1999, 11 cases have been confirmed in Indiana and two additional cases are under investigation. In the past five years, the cases have been reported from Crawford, Harrison, Warrick, Martin, Perry, Spencer, and Madison counties.A total of 2765 adult Amblyomma americanum ticks were collected from eight counties in southern Indiana during two field trips in May 2000. Ticks were pooled and examined for the presence of Ehrlichia chaffeensis using nested PCR with primers HE1 and HE3, specific for the 16S rRNA gene of the pathogen. Ninety-six pools of A. americanum specimens tested positive for E. chaffeensis DNA. This represented a minimum infection rate (MIR) of 3.5%.To identify different genetic forms (strains) of E. chaffeensis, the positive tick pools were probed for the Variable Length PCR Target (VLPT) gene of E. chaffeensis. The data were used to develop a geographic map of the distribution of the different strains of the pathogen. Overall, nine different genetic variants (91HE17, Arkansas, Jax, Liberty, Osceola, Sapulpa, St. Vincent, Wakulla, West Paces) of E. chaffeensis were identified from pools of ticks collected in four counties (Harrison, Perry, Pike, Warrick). All samples positive for the 16S rRNA were also positive for the VLPT gene.E. chaffeensis isolates are polymorphic in the number of repetitive sequences within the genes encoding the VLPT, and the isolates obtained illustrate this phenomenon. The high concordance rate between the 16S rRNA and the VLPT gene reveals that the VLPT gene is a very sensitive tool for detecting E. chaffeensis in the lone star ticks. We found no clear correlation between geographic distribution of different genetic variants of E. chaffeensis and the genetic polymorphism of the VLPT gene. Further study with a relatively larger sample size from a wider geographical area might be able to detect such a pattern. / Department of Physiology and Health Science
164

Influence of co-infection on the infection density of Borrelia burgdorferi and Ixodes scapularis endosymbiont in Ixodes scapularis ticks

Sharma, Bikram. January 2009 (has links)
Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / Department of Physiology and Health Science
165

The Effects of Climate Change on the Geographical Range of Lyme Disease in the United States as Determined by Changing Tick Distributions

King, Sarah D 01 January 2014 (has links)
Lyme disease is one of the most common infectious diseases present in the United States today and it is clear that the changing climate will affect the geographical range of it across the country. Climate change may impact the range of the Lyme vector species, ticks, which will in turn expand the range of human risk. Although I could not successfully map the possible spread of tick populations or Lyme disease incidence as a result of climate change, my research shows a direct connection between infected tick geographic distribution and key climatic variables, such as temperature, humidity, and precipitation. It is expected that as the climate changes, particularly as it warms, the range of suitable habitat for ticks will expand into high latitudes and altitudes. The expansion of tick populations will put previously unaffected human populations at greater risk of Lyme disease. It is essential that further research be done to confirm the possible consequences of climate change on Lyme disease in the United States and to gain a more precise understanding of how and where effects will be seen. Health officials and policymakers must be informed so they can properly educate and prepare people preemptively for potential Lyme disease outbreaks.
166

Considerações sobre a presença de formas promastigotas de Leishmania spp. em intestinos, ovários e glândulas salivares de carrapatos Rhipicephalus sanguineus em cães de áreas endêmicas: Milena Araúz Viol. -

Viol, Milena Araúz [UNESP] 09 June 2015 (has links) (PDF)
Made available in DSpace on 2016-05-17T16:51:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-06-09. Added 1 bitstream(s) on 2016-05-17T16:54:19Z : No. of bitstreams: 1 000864292.pdf: 560822 bytes, checksum: 00619648648254d006882132faf2729b (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / We investigated the presence of promastigotes of Leishmania spp. by immunohistochemical method in intestines, ovaries and salivary glands of Rhipicephalus sanguineus ticks in dogs. In this study, was used, 66 dogs positive and 33 negative for Leishmania spp. by immunoenzymatic test (ELISA), direct cytological examination and by polymerase chain reaction (PCR). A total of 990 ticks were collected from these 99 dogs, 10 per animal and these were dissected, with further separation of the intestines, ovaries and salivary glands. Slides of these organs were made for the implementation of immunohistochemistry (IHC). Also the real-time PCR was performed in these organs as well as the quantification of that parasite load. For real-time PCR of the guts, ovaries and salivary glands of ticks were detected positivities 93.94%, 46.97% and 27.27%, respectively. The average parasitic loads in the intestine were 9027.90 Leishmania/μL, the ovaries 411.66 Leishmania/μL and salivary glands 305.56 Leishmania/μL. Regarding the readings of IHC slides in 98.48% of the intestines, 13.64% of the ovaries and 7.58% of the salivary glands were positive for Leishmania spp. In view of these results shown by IHC technique, using the lipofosfoglicano primary antibody (LPG), we consider the possibility of the presence of promastigotes of Leishmania spp. in R. sanguineus organs / FAPESP: 2011/51113-4
167

Salivary gland transcriptome of Rhipicephalus (Boophilus) microplus

Genu, Siyamcela 11 1900 (has links)
The cattle tick, Rhipicephalus (Boophilus) microplus is a tick of veterinary and health importance globally, transmitting Babesia bovis and B. bigemina. Tick control is important and needed to prevent livestock diseases caused by tick-transmitted pathogens. Traditionally, tick control methods have resulted in development of acaricide-resistant ticks, environmental pollution and meat and milk contamination. Therefore, there is a need for alternative method and vaccines directed against tick feeding. The aim of this study was to identify proteins involved in tick feeding, tickhost-pathogen interactions and tick reproduction. Consequently, these will help in identification of antigens with the ultimate goal of developing anti-tick vaccines. R. (B.) microplus female ticks were collected at five different feeding stages. RNA was isolated from the salivary gland extracts (SGEs). The cDNA libraries were synthesized and sequenced with the Illumina MiSeq technology. Transcriptome data was analyzed with CLC Genomics Workbench, Trinity and Minia. The SGEs were also used to isolate the fractions: membrane, soluble and pellet protein for proteomic analysis. The proteomics data was analysed with Mascot, X!Tandem and Scaffold. Both the transcriptome and proteome analysis revealed the presence of major secretory protein families such as Kunitz, lipocalins, serpins, cement proteins and metalloproteases, while the majority of transcripts coded for housekeeping genes. / National Research Foundation (South Africa) / Life and Consumer Science / M. Sc. (Life Science)
168

Epidemiology and control of cattle ticks and tick-borne infections in central Nigeria

Lorusso, Vincenzo January 2015 (has links)
Cattle ticks and tick-borne infections (TBIs) undermine cattle health and productivity in the whole of sub-Saharan Africa (SSA) including Nigeria. In this West African country, two thirds of the cattle population are reared in the central-northern regions, kept under the traditional pastoral husbandry of Fulani herders. Under the Fulanis’ management, cattle are grazed extensively, being exposed to infestation by several tick genera (i.e. Amblyomma, Hyalomma, and Rhipicephalus spp., sub-genus Boophilus spp. included), vectors of the causative agents of the most important bovine TBIs in West Africa: anaplasmosis, babesiosis and ehrlichiosis (cowdriosis). Nevertheless, the Fulani pastoralists do not usually employ chemicals to control ticks in their cattle, merely relying on traditional methods (i.e. manual removal of the most conspicuous specimens). This approach, however, does not prevent cattle from being re-infested, leaving the animals challenged by a broad variety of other tick species, most of which are vectors of economically relevant TBIs. Knowledge of tick and TBIs occurrence is an essential pre-requisite to assist field diagnosis and devising effective control strategies for a given area. Existing information on tick infestation of cattle in Nigeria is rather out-dated, mostly derived from studies carried out in the south of the country. Similarly, all studies published to date on cattle TBIs in the country do not include any molecular analysis, being based instead on cytological and/or serological diagnostics. Therefore, the aim of the present thesis was to assess the presence of cattle ticks and TBIs occurring in an area of Central Nigeria (i.e. Plateau State). This is a densely populated area with traditionally managed cattle, where no acarides have historically been employed on livestock. The work undertaken herein firstly reviews the information available to date on ticks and TBIs known to be endemic in Nigerian cattle, identifying gaps present in the existing knowledge, leading to the rationale of this study. An initial survey was conducted documenting the tick species infesting cattle in Central Nigeria, in order to assess the infestation rate of surveyed animals at the time of the year when the tick load on the host is known to be most abundant (i.e. the wet season). The survey provided novel information on tick populations in cattle in Nigeria disclosing the presence of a broad variety of species, most of which are vectors of hazardous TBIs. In order to conduct a molecular diagnosis of the TBIs within the study area, a novel methodology was developed (i.e. reverse line blotting, RLB). The application of this approach was based on a thorough review of its application to the diagnosis of TBIs worldwide as well as in SSA. The optimisation of the RLB at the University of Edinburgh to enable the detection of a broad-spectrum of TBIs in Nigeria, caused by an array of five genera of microorganisms (i.e. Ehrlichia and Anaplasma, Theileria and Babesia, Rickettsia spp.) is presented. The assessment of the analytical sensitivity of this technique for the detection of Anaplasma marginale, a highly endemic tick-borne pathogen in SSA, demonstrated a detection threshold of ≥ 7 infected cells (keeping the limit of a natural infection). The occurrence of TBIs in cattle in the study area was assessed during a large-scale epidemiological survey through the application of the validated RLB. This study disclosed the occurrence of a high prevalence of several bovine TBIs in Central Nigeria, some of which are of great veterinary and zoonotic concern. The RLB enabled the detection of carrier status as well as of numerous multiple infections (69.5%, 95% CI: 65.5–73.6%). Based on the findings presented, endemic stability for highly prevalent haemoparasites (i.e. Theileria mutans, Theileria velifera, Theileria taurotragi, Anaplasma marginale, Ehrlichia species Omatjenne) is postulated, whereas a more instable epidemiological scenario is hypothesized for other microorganisms (i.e. Anaplasma centrale and Babesia bovis), which might be connected with outbreaks of clinically apparent disease, sporadically seen in the study area. The effect of a monthly tsetse-borne trypanosomiasis-focused control programme (based on the application 0.005% deltamethrin spray formulation, applied only to the lower quarters of cattle) on the kinetics of bovine TBIs was assessed at the village level. Longitudinal monitoring of control and treated cattle was conducted over the period of eleven months. Results generated provide input to the improvement of future control strategies to be rolled out across SSA, aiming to achieve an integrated control of both trypanosomiasis and TBIs. The present thesis contributes to a better understanding of the epidemiology of bovine TBIs in Nigeria as well as in the rest of West Africa, using a highly sensitive tool of wide applicability. These findings will be shared with the local pastoralist communities to further promote effective yet sustainable, vector control, in tune with the traditional long-established practices.
169

Patogeny v klíšťatech získaných ze psů a koček v Českých Budějovicích a okolí

HÁJKOVÁ, Hana January 2017 (has links)
During a period of 3 years, from March to July 2014, 2015 and 2016, ticks were collected from dogs and cats in shelter facilities for abandon animals in Česke Budejovice, South Bohemia. In total, 343 ticks were found on 106 pets: 67 domestic dogs and 39 cats. All collected ticks, that were identified as Ixodes ricinus and Ixodes hexagonus, were tested for the presence of spirochetes from Borrelia burgdorferi sensu lato (s.l.) complex, Rickettsia spp., Anaplasma spp, and Babesia spp using conventional PCR and nested PCR. Identification of pathogens was done by following sequencing of amplicons. Out of all tested ticks, 49,56% were proved to be infected at least with one pathogen. Co-infection of at least two different pathogens was determined in 18 ticks (5,2%). The aim of the present study was to estimate the role of accompanying animals (cats and dogs) in the circulation of ticks and tick-borne pathogens, to determine the frequency of pathogenic infections in dog and cat associated ticks, to evaluate the current risk of infection for dogs and cats, with respect torisk forhumans living in the area of České Budějovice.
170

Detecção de Theileria equi e Babesia caballi e anticorpos Anti-ehrlichia spp. em equídeos do Pantanal matogrossense, Brasil

Barros, Elenice Marta de 04 May 2014 (has links)
Submitted by Simone Souza (simonecgsouza@hotmail.com) on 2017-10-17T15:07:54Z No. of bitstreams: 1 DISS_2014_Elenice Marta de Barros.pdf: 718146 bytes, checksum: 4936ce6a9a93d59d120dd879462c4201 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2017-11-07T15:15:17Z (GMT) No. of bitstreams: 1 DISS_2014_Elenice Marta de Barros.pdf: 718146 bytes, checksum: 4936ce6a9a93d59d120dd879462c4201 (MD5) / Made available in DSpace on 2017-11-07T15:15:17Z (GMT). No. of bitstreams: 1 DISS_2014_Elenice Marta de Barros.pdf: 718146 bytes, checksum: 4936ce6a9a93d59d120dd879462c4201 (MD5) Previous issue date: 2014-05-04 / O presente estudo avaliou equídeos de 26 fazendas da região do pantanal matogrossense, sendo 122 equídeos testados pela Reação em Cadeia pela Polimerase (PCR) para detectar os genes de Babesia, Theileria, Anaplasma, Ehrlichia e Neorickettsia e 109 pela Reação de Imunofluorescência Indireta (RIFI) frente a antígenos de Ehrlichia canis. Das amostras testadas na PCR, 17 (14,0%) animais foram positivos. Das amostras positivas 16 foram 100% idênticas a sequencias de Theileria equi e uma foi 99% similar a sequência de Babesia caballi disponível no GenBank. Das 26 fazendas amostradas, 14 (53,8%) apresentaram equídeos positivos. Pela RIFI, 42 (38,5%) equídeos foram soropositivos para antígenos de Ehrlichia spp. sendo 27 amostras (64,3%) com títulos de 40 e 15 (35,7%) com títulos de 320. Das 25 fazendas do município de Poconé avaliadas, 18 (52,0%) apresentaram equídeos soropositivos. Os resultados do presente estudo demonstram que T. equi e B. caballi infectam equinos nos municípios de Poconé e Barra do Bugre e a presença de anticorpos anti-Ehrlichia spp. sugere a circulação entre os equídeos de espécies antigenicamente relacionadas aos gêneros Ehrlichia e Anaplasma, entretanto a negatividade nos exames de PCR pode indicar provável processo crônico desses agentes. / The present study evaluated equids from 26 ranches in the Pantanal region of Mato Grosso State. One hundred and twenty two equides were evaluated by means the Polimerase Chain Raction (PCR) to detect genes of Babesia, Theileria, Anaplasma, Ehrlichia and Neorickettsia and 109 were tested by means the Imunofluorescent Antibodie Test (IFAT) against Ehrlichia canis antigens. From the total tested in PCR, 17 (14.0%) equids were positive, and 16 yielded amplicons 100% identical to Theileria equi and one presented 99% of similarity to Babesia caballi available on GenBank. Positive equids were from 14 ranches (53.8%). Forty two (38.5%) equids were positive by IFAT and 27 showed titres of 40 (64.3%) and 15 showed titers of 320 (35.7%). From the total of 25 ranches evaluated in IFAT, 18 (52.0%) presented seropositive equids. Our results showed that T. equi and B. caballi are infecting equids in the municipalities of Poconé and Barra do Bugres and the presence of anti-Ehrlichia antibodies suggests that specie closed related to the genera Ehrlichia and Anaplasma are circulating among the equid local population. Moreover, the negative results in PCR possible is related to the chronic infection phase.

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