Submitted by Mario BC (mario@bc.ufrpe.br) on 2018-05-03T14:32:38Z No. of bitstreams: 1 Neurisvan Ramos Guerra.pdf: 2637002 bytes, checksum: 451efc2cbd7dd76dda9b010b8b0189ba (MD5) / Made available in DSpace on 2018-05-03T14:32:39Z (GMT). No. of bitstreams: 1 Neurisvan Ramos Guerra.pdf: 2637002 bytes, checksum: 451efc2cbd7dd76dda9b010b8b0189ba (MD5) Previous issue date: 2017-02-20 / The equid industry in Brazil occupies a prominent position worldwide, with about eight million equids. Diseases caused by protozoa such as Babesia caballi, Theileria equi and Neospora spp. as well as parasites that cause zoonotic protozooses such as Leishmania spp. and Toxoplasma gondii represent one of the main obstacles in the development of the sector. Therefore, this study aims to detect infection by Leishmania spp., Babesia caballi, Theileria equi, Toxoplasma gondii and Neospora spp. and their respective risk factors in equidae created with different management forms. To perform the tests, 400 samples of whole blood and serum from clinically healthy equines, including horses, mules and donkeys from 41 rural properties in the state of Pernambuco were analyzed. In order to detect Leishmania spp., direct parasitological and Polymerase Chain Reaction (PCR) tests were performed. Concerning the presence of infection by Babesia caballi and Theileria equi, direct parasitological tests and enzyme-linked immunosorbent assay (ELISA) were used for anti-Babesia caballi and anti-Theileria equi immunoglobulins detection. For the determination of seroprevalences of toxoplasmosis and neosporosis, modified agglutination (MAT) tests were used to identify anti-T. gondii IgG antibodies and anti-Neospora spp. All samples were negative for Leishmania spp. in the tests, suggesting that equidae do not participate in the epidemiological chain of leishmaniasis in the studied areas. The prevalence of anti-Babesia caballi and anti-Theileria equi antibodies of 4.3% (17/400; CI: 2.6-6.9) and the presence of B. caballi and T. equi in the serological tests revealed a prevalence of 10.8% (43/400; CI: 8.0 - 14.3), respectively, and co-infection was detected in 1% (4/400) of the animals. These data allow the characterization of areas of enzootic instability in the sites surveyed. Anti-T. gondii IgG antibodies were detected in 12.5% (50/400) of the animals analyzed. When evaluating the risk factors for T. gondii infection, only the mesoregion factor (p = 0.029) was associated with infection, particularly Zona da Mata (OR = 3). The results reveal the presence of the parasite in the studied area, which may represent a link in the transmission chain of toxoplasmosis. Seropositivity for Neospora spp. was 5.7% (23/400) and the variables age, breeding type and region presented statistical significance. In relation to age, it was observed that animals older than 11 years presented 11.8 times more chances of being serum-reactive wjhen compared with young animals (<2,5) and the prevalence found shows that the parasite is dispersed in the areas studied and that the variables age, breeding type and region are the most important risk factors for the occurrence of infection in equidae, and should be considered in the prevention of the disease. Considering the results found in the present study, the diagnosis of the various diseases present in the State of Pernambuco, when performed at an early stage, allows the application of preventive and control measures, contributing significantly to animal health and public health. / A equideocultura do Brasil ocupa posição de destaque mundial, com cerca de oito milhões de cabeças. Doenças causadas por protozoários como Babesia caballi, Theileria equi e Neospora spp. além de parasitos que causam protozooses zoonóticas a exemplo de Leishmania spp. e Toxoplasma gondii representam um dos principais entraves no desenvolvimento do setor. Diante disso, esse estudo tem como objetivo determinar as prevalências e fatores de risco associados às infecções por Leishmania spp., Babesia caballi (Nuttall & Strickland, 1910), Theileria equi (Mehlhorn & Schein, 1998), Toxoplasma gondii (Nicolle & Manceaux, 1909) e Neospora spp. em equídeos submetidos a diferentes regimes de criação. Para realização dos exames, foram analisadas 400 amostras de sangue total e soro de equídeos clinicamente saudáveis, incluindo equinos (387/400), muares (9/400) e asininos (4/400) provenientes de 41 propriedades rurais do estado de Pernambuco. Com a finalidade da detecção de Leishmania spp., foram realizados os exames parasitológicos diretos e Reação em cadeia da Polimerase (PCR). No intuito de averiguar a presença de infecção por Babesia caballi e Theileria equi foram utilizados os exames parasitológico direto e Ensaio de Imunoadsorção Enzimática (ELISA), para detecção de imunoglobulinas anti-Babesia caballi e anti-Theileria equi. Para determinação das soroprevalências da toxoplasmose e neosporose foram utilizados os testes de aglutinação modificado (MAT) para identificação de anticorpos IgG anti-T. gondii e IgG anti-Neospora spp. Todas as amostras resultaram negativas para Leishmania spp. nos testes, o que sugere que os equídeos não participam da cadeia epidemiológica das leishmanioses nas áreas estudadas. Quanto à presença de B. caballi e T. equi, os testes sorológicos revelaram uma prevalência de anticorpos anti-Babesia caballi e anti-Theileria equi de 4.3% (17/400; I.C. 2,6 – 6.9%) e 10,8% (43/400; I.C. 8.0 – 14.3), respectivamente e foi detectada co-infecção em 1% (4/400) dos animais. Tais dados permitem caracterizar como áreas de instabilidade enzoótica os locais pesquisados. Anticorpos IgG anti-T. gondii foram detectados em 12,5% (50/400) dos animais analisados. Quando avaliados os fatores de risco para infecção por T. gondii, apenas o fator mesorregião (p=0,029) apresentou associação com a infecção, particularmente Zona da Mata (OR=3). Os resultados revelam a presença do parasito na área estudada, o que pode representar um elo na cadeia de transmissão da toxoplasmose. A soropositividade para Neospora spp. total foi de 5,7% (23/400) e as variáveis idade, tipo de criação e região apresentaram significância estatística. Em relação à idade, observou-se que animais acima de 11 anos apresentaram 11,8 vezes de chances a mais de serem sororreagentes quando comparados com os animais jovens (<2,5) e a prevalência encontrada demonstra que o parasito está disperso nas áreas estudadas e que as variáveis idade, tipo de criação e região são fatores de riscos mais importantes para ocorrência da infecção em equídeos, devendo ser considerados na prevenção da doença. Considerando os resultados encontrados no presente estudo, o diagnóstico das diversas doenças presentes no estado de Pernambuco, quando realizado de forma precoce, possibilita a aplicação de medidas preventivas e de controle, contribuindo significativamente com a sanidade animal e saúde pública.

Corridor disease (Theileria parva infection in cattle associated with carrier buffaloes) was not reported to cause serious outbreaks prior to 1994. From 2002-2004, outbreaks in cattle have increased in the areas where the disease is endemic in buffalo populations. In this study, the occurrence of Corridor disease outbreaks in the Zululand district municipality was closely monitored from 2004-2009. The observations included the number of cattle involved in the outbreaks, clinical signs, parasitological and post-mortem examinations while blood for serum and in EDTA were collected for serological (IFA test) and molecular (real-time PCR) tests specific for T. parva. Samples were collected from cattle involved in the outbreak, the sick and presumed recovered cattle. Recovered cattle from the farms were brought to the laboratory at the Onderstepoort Veterinary Institute for further investigations. This included tick pick-up and transmission attempts to demonstrate their carrier status as well as assessing their immunity to further experimental challenge using virulent T. parva stabilate. Results were obtained on Corridor disease outbreaks in the study area and ad hoc locations comprising a total of 15 commercial farms and community diptanks in the district from 2004 to 2009. A total of 31 outbreaks were recorded during the study period. The number of outbreaks per year was stable, being 3 or 4 from 2004 to 2007. A 100 percent increase was recorded in the subsequent years, 2008-2009. In one location, Morgenzon farm comprising a commercial and community farmers, had experienced regular outbreaks from 2004-2009. It is also noted that some farms experienced outbreaks for three consecutive years. Three other farms had experienced outbreaks for the first time in either 2008 or 2009. The most severe outbreak occurred in Nyalisa in 2009 where the disease was experienced for the first time in one herd in which 202 cattle were involved and 57 died within 30-40 days after the onset of the disease. Using all the tools mentioned above, the cause of death was confirmed to be due to T. parva infection. The Corridor disease outbreaks that were investigated, have mostly been reported during the months from March-May (88 %) but some (8 %) were encountered during the winter months (June-August). The distribution of outbreaks mainly coincided with the activity period of adult R. appendiculatus. During the investigation period, a total of 846 cattle were tested for Corridor disease and the prevalence was found to be 27 %. The percentage of cattle which were found positive by PCR was 16.5. Seven percent were found positive on both PCR and IFA tests, an indication of the development of a carrier state. However, 10 % of the cattle remained sero-positive with no indication of being parasite-carriers (real-time PCR negative). Five cattle which recovered from an apparent severe T. parva infection in the field and confirmed to be positive by PCR, all became negative before they were used in the transmission experiments. Ticks derived from these cattle were used to infect susceptible bovines but only T. taurotragi was transmitted. The xeno-diagnosis failed to demonstrate the carrier state in these field cattle. The five Corridor disease recovered cattle obtained from different study locations mentioned above, received lethal challenge using T. parva buffalo-derived stabilate. All challenged animals, including the susceptible control, showed schizont parasitosis as detected by the T. parva</i. real-time PCR test starting day 11 to 23. All animals also developed significant antibody titer to T. parva by day 28. Of the field cattle, only one bovine which showed mild reactions manifested by high temperature on day 11 for two consecutive days and schizonts parasitosis in lymph nodes on day 15 for only two days and recovered. The rest of the field cattle did not show any clinical or parasitological reactions during the observation period (103 days). The control bovine had high fever and showed schizonts parasitosis by day 11 for seven consecutive days. The reaction was classified as severe and had to be treated. Unfed R. appendiculatus collected off grass from one of the study sites were applied to feed on a susceptible bovine and only T. taurotragi was transmitted. There were no apparent clinical signs and the animal behavior kept normal during the observation period (60 days). This study suggests that Corridor disease should be considered as an “emerging disease” and more stringent control methods should be implemented. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Veterinary Tropical Diseases / unrestricted

The aim of this study was to investigate three key epidemiological aspects of Theileria parva infections in cattle and African buffalo (Syncerus caffer) in South Africa. The first of these was the possible behavioural change (i.e. transformation) of buffalo-derived T. parva (causing classical Corridor disease in cattle) to what might be considered cattle-derived T. parva (causing classical East Coast fever in cattle) after repeated tick-passage in cattle. For the first time a South African isolate of buffalo-derived T. parva was successfully transmitted using Rhipicephalus zambeziensis for eight passages in non-splenectomised cattle. This was achieved despite most animals developing fatal infections with extremely low piroplasm parasitaemias, and without chemotherapeutic intervention. This finding indicates that, contrary to earlier belief, Corridor disease is not a self-limiting disease in cattle, and given the opportunity, could well become established in a cattle population in the absence of buffalo. Despite repeated tick transmission in cattle of the South African buffalo isolate of T. parva used in this study, it did not exhibit the behavioural changes associated with “transformation” to typical cattle-derived T. parva. Secondly, the potential role of the common waterbuck (Kobus ellipsiprymnus) in the selection of cattle-adapted subpopulations of parasites from buffalo-derived T. parva was investigated. Waterbuck captured in Kruger National Park (KNP) were screened by conventional and molecular diagnostic techniques for Theileria spp. infections. Laboratory-reared R. zambeziensis were fed on captive buffalo confirmed to be naturally infected with T. parva. The ensuing adult ticks were fed on captive waterbuck and cattle. All the waterbuck were found to carry microscopically detectable Theileria sp. piroplasm infections, found by polymerase chain reaction (PCR) diagnosis to belong to a hitherto uncharacterised Theileria species. R. zambeziensis adults which fed as nymphs on the buffalo transmitted fatal T. parva infections to cattle. However, no transmission of T. parva to the waterbuck could be demonstrated clinically or by PCR diagnosis. Also, R. zambeziensis nymphs that were subsequently fed on the waterbuck failed to transmit T. parva to cattle in the ensuing adult stage, confirming the absence of T. parva-group infections in the waterbuck. The results suggest that buffalo in KNP probably do not carry T. parva-group parasites which are readily transmissible to common waterbuck and waterbuck are therefore unlikely to play an important role in the epidemiology of T. parva-group infections in cattle in South Africa. Thirdly, to investigate the carrier state of buffalo-derived T. parva infections in cattle, blood from infected non-splenectomised and splenectomised carrier cattle was subinoculated to splenectomised cattle. T. parva infections were successfully transmitted by subinoculation of 1000 ml of blood at various intervals after infection to splenectomised recipient cattle. Donor animals comprised of recovered intact cattle, reacting intact cattle or splenectomised recovered cattle. Microscopically detectable piroplasm parasitaemias were detected in all recipients after inoculation. One splenectomised recipient developed a moderate clinical reaction, accompanied by a moderate schizont parasitosis, but recovered spontaneously, confirming persistence of schizonts in some T. parva carrier animals. By contrast, a T. parva piroplasm infection, persisting in a treated recovered splenectomised bovine, in the apparent absence of circulating schizonts, was serially (consecutively) passaged in splenectomised cattle. Seroconversion occurred in all recipient cattle. With the exception of the recipient which developed a clinical reaction and circulating schizonts, none of the recipients showed any clinical signs of T. parva infection. Upon homologous sporozoite challenge with T. parva, two out of three recipient animals with only microscopically detectable piroplasm parasitaemias developed fatal T. parva infections and one recovered after exhibiting severe clinical signs. These findings confirm the stage-specific immunity in T. parva and, contrary to popular belief, the possibility of long-term maintenance of piroplasm parasitaemias in the absence of schizonts in carrier cattle. The technique of subinoculating and establishing virulent T. parva carrier infections in splenectomised cattle also provides a method whereby buffalo-derived parasite stocks may be isolated and maintained for characterisation and the preparation of sporozoite stabilates for inclusion in T. parva vaccines. Copyright / Dissertation (MSc)--University of Pretoria, 2011. / Veterinary Tropical Diseases / unrestricted

Of the four most economically important tickborne diseases of cattle in the world, two have been identified in Virginia, occasionally as co-infections: anaplasmosis and theileriosis. The latter is caused by the emerging infectious agent, the Theileria orientalis complex, in particular the Ikeda and Chitose genotypes. These organisms are carried by the ixodid tick, Haemaphysalis longicornis, recently identified in the United States. Our work has been focused on initially identifying the protozoal organisms, crafting assays to aid in the identification of these organisms in clinically affected animals, and briefly examining the rate of co-occurrence of theileriosis and anaplasmosis. This is important, as Anaplasma marginale - the most common etiologic agent of anaplasmosis in cattle in Virginia - is treatable with a safe, effective, FDA-approved compound, whereas there is no currently approved treatment for theileriosis. Finally, we seek to contextualize theilerosis as a cause of infectious bovine anemia (IBA) and its expected economic impact on the cattle industry in Virginia. / Doctor of Philosophy / Theileriosis is a disease that infects cattle, caused by the blood parasite, Theileria orientalis, specifically two distinct genotypes of T. orientalis, Ikeda and Chitose. Theileriosis is transmitted to cattle by the Asian longhorned tick, Haemaphysalis longicornis, which was recently identified in the United States. Globally, theileriosis is one of four major tickborne diseases of cattle with significant economic importance, so the discovery of this parasite in the state of Virginia is of special importance to the cattle industry in Virginia. My work has revolved around making the initial discovery of T. orientalis Ikeda in the United States, and developing tests for cattle producers and veterinarians to use to help diagnose theileriosis in sick animals. Another tickborne disease of cattle, anaplasmosis, is caused by a bacterium, A. marginale. These two organisms have different biology, are transmitted by different ticks, and are treated differently, but cause identical clinical disease in cattle. In addition to identifying T. orientalis, we have developed a single test that can determine if sick cattle have T. orientalis or A. marginale – this is important, because the antibiotic used to treat A. marginale does not work to treat T. orientalis. In fact, there is no treatment for T. orientalis available in the United States. In addition to developing diagnostic assays, I seek to put into pathobiological, ecological, and economic context the importance of theileriosis on the cattle industry in Virginia.

Made available in DSpace on 2016-04-28T20:16:24Z (GMT). No. of bitstreams: 1 2007- Katia Roberta Fernandes.pdf: 2143619 bytes, checksum: 6ff7127f4642317cf1f53d7aceb93f1f (MD5) Previous issue date: 2007-02-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The aim of the present study was to evaluate the natural and experimental infection of B. equi in nymphs and adult Boophilus microplus using optical microscopy and molecular analysis. The experimental infection was observed in nymphs, males and females of B. microplus fed on equines chronically infected with B. equi and in non fed larvae and eggs. For the experiments two equines, of not defined breed, proven to be infected with B. equi were used. The animals were infested with B. microplus larvae of generation F4 obtained from a laboratory maintained population, known to be free of Babesia spp. infection. Daily collections of ticks were realized using as starting point the ecdisys to nymph state. After the collection the hemolymph was examined and the intestine and salivary glands were dissected, smashed on glass slides for microscopy, methanol treated and stained with Giemsa. There were dissected 860 specimens (432 nymphs, 280 females and 148 males). The dissected salivary glands were divided into two parts. The first one was smashed on microscopy glass slides, stained and examined by optical microscopy for morphologic analyses. From the second part was realized DNA extraction and PCR with specific primers for the 18S rRNA. On optical microscopy of nymph hemolymph was possible to be observed the presence of kinetes with claviform aspect characteristic for the genus Babesia. In the salivary glands of B. microplus nymphs the morphology and the sequence of developmental stages of B. equi were observed initiating on day 4 after ecdysis, being possible to see in acinary cells the formation of sporoblasts and ovoid sporozoites measuring 1.5 &#956;m of diameter and elongated sporozoites with 3.8 to 5.2&#956;m of length and 0.8 to 1.5 &#956;m of width. The PCR confirmed the presence of B. equi in DNA samples extracted from salivary glands of nymphs, male and female ticks as well as in larvae and eggs. To evaluate the natural infection were collected nymphs and adult B. microplus from two equines naturally infested by these ticks and naturally infected with B. equi. These horses were originated from Seropedica city in the state of Rio de Janeiro. There were dissected 324 specimens (145 nymphs, 138 females and 41 males). The proceedings with the salivary glands were identical to the previously described for the experimental infection. Of the salivary glands submitted to PCR, 70% showed to be infected with B. equi. Microscopical analysis of the salivary glands revealed the presence of sporoblast stages and the development of elongated sporozoites in acinary glands. The morphologic, morphometric and molecular analysis confirmed the experimental and natural infection of the salivary glands of nymphs and adult B. microplus with B. equi. The results of the present study show the ability of B. equi to develop in this tick species. The detection of B. equi DNA in eggs and larvae also suggests the possibility of transovarian transmission in B. microplus. The results allow to consider the tick B. microplus as a potential biologic vector of B. equi in horses from the studied region. / Este trabalho teve como objetivo avaliar a infec??o natural e experimental de Babesia equi em ninfas e adultos de Boophilus microplus por meio de microscopia ?ptica e an?lise molecular. A infec??o experimental foi observada a partir de ninfas, machos, f?meas, ovos e larvas n?o alimentadas de B. microplus alimentados em equinos com infec??o cr?nica por B. equi. Para a realiza??o do experimento foram utilizados dois eq?inos, mesti?os, com infec??o por B. equi. Os animais foram infestados com larvas de B. microplus de gera??o F4 obtidas de col?nia mantida em laborat?rio e livres de infec??o por Babesia spp. A partir da ecdise para ninfa foram realizadas coletas di?rias. Ap?s a coleta foram realizados os exames de hemolinfa e extra??o do intestino e das gl?ndulas salivares os quais foram macerados em l?minas de vidro para microscopia, fixados em metanol e corados com Giemsa. As gl?ndulas salivares dissecadas foram divididas em duas partes. A primeira parte foi macerada em l?minas de vidro para microscopia, corada com corante Giemsa e observada em microsc?pio ?tico para an?lise morfol?gica. A segunda parte foi realizada a extra??o de DNA, sendo submetida a PCR com primers especif?cos para o gene 18S rRNA para B. equi. Foram dissecados 860 esp?cimes (ninfas= 432; f?meas= 280 e machos= 148). Na microscopia ?ptica foi poss?vel observar nas hemolinfas das ninfas a presen?a de cinetos com aspecto claviforme t?picos do g?nero Babesia. Nas gl?ndulas salivares, a morfologia e a seq??ncia dos est?gios de desenvolvimento de B. equi das ninfa s de B. microplus, foram observadas a partir do 4? dia ap?s ecdise, sendo poss?vel observar nos ?cinos celulares a forma??o de esporoblastos e de esporozo?tas ov?ides medindo 1,5 &#956;m de di?metro e alongados medindo 3,8 a 5,2&#956;m de comprimento e 0,8 a 1,5&#956;m de largura. A rea??o em cadeia de polimerase (PCR) confirmou a presen?a de B. equi em DNA de gl?ndulas salivares extra?das de ninfas, machos, f?meas, assim como dos ovos e larva. A infec??o natural foi observada a partir de ninfas e adultos de B. microplus coletados de dois eq?inos naturalmente infestados e comprovadamente infectados por B. equi, procedentes do munic?pio de Serop?dica, Rio de Janeiro. Foram dissecados 324 esp?cimes (ninfas= 145, f?meas= 138 e machos= 41). O processamento das gl?ndulas salivares dissecadas foi semelhante ao descrito para infec??o experimental. Das gl?ndulas salivares submetidas a PCR, 70% apresentaram resultados positivos para B. equi. As an?lises por microscopia ?ptica das gl?ndulas salivares das ninfas e dos adultos revelaram a presen?a nos ?cinos celulares os est?gios de esporoblastos e o desenvolvimento de esporozo?tas alongados. As an?lises morfol?gicas, morfom?tricas e moleculares confirmaram a infec??o experimental e natural das gl?ndulas salivares de ninfas e adultos de B. microplus por B. equi. Os resultados deste estudo demonstram a capacidade de multiplica??o de B. equi em gl?ndulas salivares de ninfas e adultos de B. microplus. A detec??o de DNA de B. equi em ovos e larvas de B. microplus tamb?m sugere a possibilidade da transmiss?o transovariana nesta esp?cie de carrapato. Estes resultados sugerem que o carrapato B. microplus ? vetor biol?gico de B. equi na regi?o estudada.

Theileria parva is an intracellular protozoan parasite and the causative agent of the lethal livestock disease East Coast fever (ECF). Research has shown that a protective cell-mediated immune response against parasite-infected lymphocytes is capable of clearing the host of T. parva (Pearson et al. 1979), leaving the host solidly immune to reinfection. The work presented in this thesis describes my attempts to develop a method for identification of major histocompatibility complex class I-associated T. parva peptides involved in eliciting this protective cell-mediated immune response. The soluble chaperone gp96 interacts with peptides destined for association with major histocompatibily complex class I molecules and is therefore a source of T. parva peptides that interact with extracellular immune effectors. Using sensitive mass spectrometry methods the gp96-chaperoned peptide proteome from model parasite infected T lymphocytes was compared to an uninfected T cell line. With our findings we have demonstrated proof of concept for a highly sensitive method for the elucidation of potentially immunogenic peptides capable of initiating a protective immune response against the intracellular parasite T parva.

Attività antropiche e pressioni di mercato stanno rapidamente riducendo la biodiversità. Per questa ragione, conservare il patrimonio ecosistemico, tassonomico e genetico risulta fondamentale al fine di garantire potenziale adattativo alle specie, e, in ultima analisi, un futuro sostenibile per il pianeta. Al fine di minimizzare la perdita di biodiversità, numerosi metodi sono stati proposti per priorizzare ecosistemi, specie e popolazioni. Il presente lavoro di tesi fornisce in primo luogo una revisione di tali approcci, proponendo un albero decisionale volto a favorirne un corretto utilizzo. Secondariamente, la variabilità genomica neutrale del bufalo d’acqua (Bubalus bubalis L.) è investigata per mezzo di un pannello di marcatori SNP a media densità, rivelando due centri di domesticazione (India Nord-occidentale, Cina-Indocina) e possibili rotte di migrazione per gli ecotipi ‘river’ e ‘swamp’. L’adattamento locale ad East Coast Fever, patologia endemica delle popolazioni bovine in Africa Sub-sahariana, è stato inoltre studiato in bovini autoctoni Ugandesi (Bos taurus L.) combinando tecniche di modellizzazione delle nicchie ecologiche e di genomica del paesaggio. L’approccio ha portato ad indentificare PRKG1 e SLA2 come possibili geni di adattamento. I risultati sono discussi alla luce delle possibili implicazioni nella conservazione del bufalo e nella gestione delle risorse genetiche animali Ugandesi. / Biodiversity is quickly disappearing due to human impact on the biosphere, and to market pressure. Consequently, the protection of both wild and domestic species needs to become a priority in order to preserve their evolutionary potential and, ultimately, guarantee a sustainable future for coming human generations. To date, tens of methods have been proposed to prioritize biodiversity for conservation purposes. Here, an ontology for priority setting in conservation biology is provided with the aim of supporting the selection of the most opportune methodologies given specific conservation goals. Further, two case studies are presented characterizing neutral and adaptive genomic diversity in water buffalo (Bubalus bubalis L.) and indigenous Ugandan cattle (Bos taurus L.), respectively. In particular, two independent domestication centres (North-western India and Indochina) and separate migration routes are suggested for the ‘river’ and ‘swamp’ water buffalo types. In the case of indigenous Ugandan cattle, the integration of species distribution modelling and landscape genomics techniques allowed the identification of PRKG1 and SLA2 as candidate genes for local adaptation to East Coast Fever, a vector-borne disease affecting bovine populations of Sub-Saharan Africa. Results are discussed for their implications in water buffalo conservation and Ugandan cattle adaptive management.

Text in English / Corridor disease is an economically important tick-borne disease of cattle in southern Africa. The disease is caused by Theileria parva and transmitted by the vectors, Rhipicephalus appendiculatus and R. zambeziensis. There is currently no vaccine to protect cattle against T. parva that is permitted in South Africa. To develop recombinant anti-tick vaccines against Corridor disease, comprehensive databases of genes expressed in the tick’s salivary glands are required. Therefore, in Chapters 2 and 3, mRNA from the salivary glands of R. appendiculatus and R. zambeziensis was sequenced and assembled using next generation sequencing technologies. Respectively, 12 761 and 13 584 non-redundant protein sequences were predicted from the sialotranscriptomes of R. appendiculatus and R. zambeziensis and uploaded to public sequence domains. This greatly expanded the number of sequences available for the two vectors, which will be invaluable resources for the selection of vaccine candidates in future. Further, in Chapter 3, differential gene expression analysis in R. zambeziensis revealed dynamic expression of secretory protein transcripts during feeding, suggestive of stringent transcriptional regulation of these proteins. Knowledge of these intricate expression profiles will further assist vaccine development in future. In Chapter 4, comparative sialotranscriptomic analyses were performed between R. appendiculatus and R. zambeziensis. The ticks have previously shown varying vector competence for T. parva and this chapter presents the search for correlates of this variance. Phylogenetic analyses were performed using these and other publically available tick transcriptomes, which indicated that R. appendiculatus and R. zambeziensis are closely related but distinct species. However, significant expression differences were observed between the two ticks, specifically of genes involved in tick immunity or pathogen transmission, signifying potential bioinformatic signatures of vector competence. Furthermore, nearly four thousand putative long non-coding RNAs (lncRNAs) were predicted in each of the two ticks. A large number of these showed differential expression and suggested a potential transcriptional regulatory function of lncRNA in tick blood feeding. LncRNAs are completely unexplored in ticks. Finally, in Chapter 5, concluding remarks are given on the potential impact the R. appendiculatus and R. zambeziensis sialotranscriptomes may have on future vaccine developments and some future research endeavours are discussed. / Life and Consumer Sciences / Ph. D. (Life Sciences)