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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.
71

Rough leucine auxotrophic strains of <i>Brucella</i> expressing <i>Salmonella</i> flagellin C conjugated gonadotropins, an immunocontraceptive brucellosis vaccine for feral swine population control

Waldrop, S. Grant January 2020 (has links)
Brucellosis, caused by Gram-negative bacteria of the genus <i>Brucella</i>, is a zoonotic disease with global impacts on human, livestock, and wildlife health. Around 500,000 cases of human brucellosis are reported by the World Health Organization annually. Even though brucellosis has been eradicated from domestic livestock in the United States of America, the causative bacterial pathogen is still present in elk, bison, and feral swine. With the growth of free-range farming, domestic livestock and wildlife populations come into close contact, spreading the disease. Feral swine interactions are of particular concern. They carry a number of zoonotic diseases including brucellosis. As there is no commercial vaccination protocol to prevent brucellosis in wildlife and swine, interactions with these populations are especially dangerous for public health. Feral swine population is increasing nationwide even with the current population control practices. There is an urgent need for efficient control of feral swine and preventing the spread of brucellosis. To aid in the prevention of the spread of feral swine across the USA, immunocontraceptives have been employed. Over the years several candidates have been tested, but the search for the perfect vaccine is still ongoing. The monumental task includes reversibly preventing one of life’s most basic necessities, reproduction, through an oral route with no effect on non-target species. One way that science is tackling both of these threats at once is through dual-purpose vaccines. Dual-purpose vaccines produce an immune response that targets two different pathogens, or in this case a pathogen and reproductive hormones. In the effort to produce this vaccine, more knowledge was needed in regards to <i>B. neotomae</i>. This dissertation showed that it has the ability to survive in a variety of cells from different species, in a similar manner to known virulent <i>Brucella</i> species. This is of concern when using <i>B. neotomae</i> as a vaccine, but it has also been shown that attenuated <i>B. neotomae</i> can provide protection against virulent <i>B. suis, B. abortus</i>, and <i>B. melitensis</i> challenge. This is a major finding in the effort towards a universal brucellosis vaccine. After genetic manipulation, cell culture assays, and mouse trials, several leucine auxotrophic <i>B. neotomae</i> and <i>B. abortus</i> strains show promise in the effort towards a dual-purpose vaccine. Strains of <i>B. neotomae</i> <i>ΔwboA ΔleuB</i> pNS4-trcD-fliC-Gonadotropins were discontinued in this effort towards a brucellosis immunocontraceptive dual-purpose vaccine due to lethality issues in mice. These stability and lethality issues are still under investigation. Instead, a proven stable strain of <i>B. abortus</i> RB51 (a USDA approved cattle vaccine) was used to investigate its effects on fertility in mice when expressing fliC-Gonadotropins. Strains <i>B. abortus</i> RB51 ΔleuB pNS4-trcD-fliC-porcineFSHβ (RB51LFSHβ) and <i>B. abortus</i> RB51 ΔleuB pNS4-trcD-fliC-GnRH (RB51LGnRH) confer reduced fertility characteristics in both male and female purpose bred mice. Strain RB51 ΔleuB has also been shown to protect against virulent <i>B. abortus</i> challenge in the literature. These findings warrant further investigation to determine the efficacy of these vaccine strains in swine as an oral vaccine. Ultimately, their ability to prevent brucellosis, while causing immunocontraception needs to be determined in feral swine. / Ph.D. / While brucellosis has been eradicated from domestic livestock in the United States, the causative agent is still present in wildlife like elk, bison, and feral swine. The interactions between these infected wildlife populations with domestic livestock and human populations pose a great health risk. Many tools are employed to mitigate these interactions including vaccination programs and population management. In particular, the feral swine population has proven difficult to control. It has quadrupled in the past ten years and continues to expand nationwide, making their population control an important national objective. Furthermore, feral swine are known carriers of zoonotic diseases, including hemorraghic colitis, leptospirosis, trichinosis, swine influenza, and brucellosis. Many cases of these diseases in humans have been traced back to interactions with feral swine. The current population control practices have failed to minimize the $1.5 billion of damage they cause to the agricultural industry per year. Thus, there is a need to effectively control the feral swine population and prevent the spread of zoonotic diseases like brucellosis. Rough leucine auxotrophic strains of <i>Brucella</i> expressing gonadotropin releasing hormone (GnRH) or porcine follicle stimulating hormone beta subunit (FSH) conjugated to <i>Salmonella</i> fliC show promise. They have been shown to provide protection from virulent Brucella strain challenge and reduce fertility characteristics in mice. Their effectiveness as an immunocontraceptive for feral swine management, while reducing the spread of brucellosis needs to be tested in swine. These vaccine strains [<i>B. abortus</i> RB51 ΔleuB pNS4-trcD-fliC-porcineFSHβ (RB51LFSHβ), <i>B. abortus</i> RB51 ΔleuB pNS4-trcD-fliC-GnRH (RB51LGnRH) and <i>B. neotomae ΔwboA ΔleuB</i> pNS4-trcD-fliC-GnRH (BNWLGnRH)] could pave the way for effective novel immunocontraceptive tools to be used in wildlife management.
72

Screening for enteric coronaviruses in fecal samples of feral pigs of California, USA

Ghimire, Shristi 21 September 2017 (has links)
No description available.
73

Fearful to Friendly (F2F): a Constructional Fear Treatment for Domestic Cats Using a Negative Reinforcement Shaping Procedure in a Home Setting

Rentfro, Angela Drake 08 1900 (has links)
Feral and fearful cats and kittens in animal shelters are not likely to be adopted as companion animals because they emit fearful or aggressive behaviors in the presence of humans. The purpose of the fearful to friendly (F2F) research was to investigate a shaping procedure to increase friendly behaviors of feral and fearful domestic cats and kittens with the goal of achieving animal shelters’ adoptability criteria. The results showed the F2F procedure was a safe and very effective procedure to quickly tame feral kittens deemed unadoptable. The day after implementing F2F, three out of four kittens approached me and accepted petting and holding without any additional training.
74

Factors That Affect Harem Stability in a Feral Horse (Equus caballus) Population on Shackleford Banks island, NC

Madosky, Jessa 04 August 2011 (has links)
Mammal species often live in social groups, but the factors that promote group cohesion can be difficult to analyze due to the prevalence of strong group affiliations. Feral horses maintain stable harems of one or two males and several females, and harem stability is strongly related to individual fitness. Anecdotal evidence and an early study in the non-breeding season suggest that management of the Shackleford Banks island horses with immunocontraception reduces harem stability in the population, providing an opportunity to study the factors that influence harem stability. I investigated the effects of the immunocontraceptive PZP on harem stability during the breeding season and examined mare activity budgets and harassment rates to determine if these factors influence harem stability. I hypothesized that 1) immunocontraception would increase the rates at which mares changed harems during the breeding season 2) activity budgets of contracepted individuals would differ significantly from those of uncontracepted individuals, and 3) contracepted mares would experience greater levels of harassment associated with changing harems than uncontracepted mares. I found that the immunocontraceptive does increase harem changes during the breeding season. I also found that contracepted mares have different activity budgets than uncontracepted mares; as predicted, contracepted mares grazed less and moved more than uncontracepted controls. The factors that influence mare activity budgets included immunocontraception, harem stallion, number of individuals in the harem, number of mares in the harem and body condition of the mare, as well as some interactions between factors. I found that high harassment rates by both harem stallions and other mares in the harem are correlated with higher harem change rates and that contracepted mares are harassed more than uncontracepted mares. These results indicate that the immunocontraceptive does influence harem stability in this feral horse population, potentially through alterations in activity budgets and harassment rates.
75

Effective contact of cattle and feral swine facilitating potential foot-and-mouth disease virus transmission in southern Texas, USA rangeland

De La Garza, Guadalupe Ray, III 15 May 2009 (has links)
For the second study, a web-based survey was developed and distributed to all members of four major health education organizations. A total of 1,925 HEs’ completed the survey and 1,607 responses were utilized in the final analysis. This study indicated that participants had deficient knowledge and unfavorable attitudes toward the CDCproposed genomic competencies. In the third study, a theoretical model was developed to predict HEs’ likelihood to incorporate genomic competencies into their practice. Using techniques from Structural Equation Modeling (SEM), the model was tested with the same data of the second study. Findings supported the proposed theoretical model. While genomic knowledge, attitudes, and self-efficacy were significantly associated with HEs’ likelihood to incorporate genomic competencies into their practice, attitudes was the strongest predictor of likelihood. In summary, these studies indicated that participating HEs had deficient genomic knowledge, unfavorable attitudes toward a set of CDC-proposed genomic competencies, and low likelihood to adopt genomic competencies into health promotion. Relevant training should be developed and advocated. As the SEM analysis results indicated the survey findings supported the proposed theoretical model, which can be utilized to steer future training for HEs. statistics, 2) unadjusted inferential statistics, 3) stratified analysis, and 4) multivariable models. My investigation produced results in accord with generally accepted notions in addition to significant findings that interestingly counter current preconceptions. Intraspecies contact was more common than inter-species, with indirect contact occurring more frequently than direct. Direct contact between species occurred extremely rarely. The most important factors that influenced the rate of contact for both species were water, winter, and cultivated fields. Information regarding probability of infectious agent survival and transfer will be used in the future to advance current epidemiological models, including geographicautomata (Ward et al. 2007: In Press) and cellular automata models (Doran and Laffan 2005) to better understand and manage integrated domestic cattle and free-ranging wildlife populations. Such modeling provides essential and necessary knowledge for developing prevention, detection, response, and recovery strategies – employed in advance, during, and after a disease outbreak, respectively.
76

Habitat Selection by Feral Horses in the Alberta Foothills

Bevan, Tisa L Unknown Date
No description available.
77

[pt] ANTROPOCENO MAIS-QUE-HUMANO NA BAIXADA DE JACAREPAGUÁ: DINÂMICAS SOCIOAMBIENTAIS E ECOLOGIAS FERAIS / [en] MORE-THAN-HUMAN ANTHROPOCENE IN BAIXADA DE JACAREPAGUÁ: SOCIOENVIRONMENTAL DYNAMICS AND FERAL ECOLOGIES

FERNANDO PATRICIO RIBEIRO 24 November 2023 (has links)
[pt] A presente tese visa apresentar uma perspectiva antropológica para a crise ambiental da Baixada de Jacarepaguá, situada na cidade do Rio de Janeiro, ao longo do século XX. Mais especificamente, essa perspectiva busca compreender a história dessa crise a partir da intensa transformação das águas e da terra, inserindo as ações antrópicas locais no contexto global de ações humanas que mudaram a relação entre os seres humanos e não humanos que configuram o Antropoceno-mais-que-humano da antropóloga Anna Tsing. Ao longo do século XX, principalmente a partir dos anos 1970, após a aprovação do Plano Piloto do arquiteto Lúcio Costa, as inúmeras e aceleradas ações humanas para modernizar a região, como as obras de infraestrutura urbana e os frequentes lançamentos de diversos empreendimentos imobiliários pelos agentes da transformação – poder público e empreendedores - iniciaram uma crise ambiental local que foi acentuada pelo comportamento feral de algumas espécies, como o crescimento descontrolado das gigogas e floração das cianobactérias em todo o complexo lagunar da baixada. Além disso, enquanto as tilápias, uma espécie exótica, contribuíram para a mudança na ecologia da ictiofauna, o jacaré-de-papo-amarelo, espécie local, passou a ser um reflexo dessas ações antrópicas, quando seu corpo foi deformado por conta da ingestão de plástico e outros produtos inorgânicos oriundo das atividades humanas. A transformação da paisagem e do comportamento das espécies proporcionou alteração na vida daquelas pessoas que dependem dos recursos naturais provenientes das águas do complexo lagunar. Dessa forma, a crise ambiental desencadeada por conta tanto da intensa e acelerada transformação da região quanto do comportamento feral de algumas espécies da Baixada talvez possa ser entendida como um exemplo local, dentre tanto outros pelo mundo, que revelam os riscos do Antropoceno. / [en] This thesis aims to present an anthropological perspective on the environmental crisis in Baixada de Jacarepaguá, located in the city of Rio de Janeiro, throughout the 20th century. More specifically, this perspective seeks to understand the history of this crisis based on the intense transformation of water and land, inserting local anthropic actions in the global context of human actions that changed the relationship between human and non-human beings that shape the More –than- human - Anthropocene by the anthropologist Anna Tsing. Throughout the 20th century, mainly from the 1970s onwards, after the approval of architect Lúcio Costa s Pilot Plan, the countless and accelerated human actions to modernize the region, such as urban infrastructure works and the frequent launches of various real estate projects by agents of transformation – public authorities and entrepreneurs – initiated a local environmental crisis that was accentuated by the feral behavior of some species, such as the uncontrolled growth of gigogas and the bloom of cyanobacteria throughout the lagoon complex of the Baixada. Furthermore, while tilapia, an exotic species, contributed to the change in the ecology of the ichthyofauna, the broad-snouted caiman, a local species, became a reflection of these anthropic actions, when its body was deformed due to ingestion plastic and other inorganic products arising from human activities. The transformation of the landscape and the behavior of species led to changes in the lives of those people who depend on natural resources from the waters of the lagoon complex. In this way, the environmental crisis triggered by both the intense and accelerated transformation of the region and the feral behavior of some species in the Baixada can perhaps be understood as a local example, among many others around the world, that reveal the risks of the Anthropocene.
78

Populationsbiologie, Raumnutzung und Verhalten verwildeter Hauskatzen und der Effekt von Maßnahmen zur Reproduktionskontrolle

Kalz, Beate 28 May 2001 (has links)
In einem 45 ha großen Untersuchungsgebiet in der Innenstadt von Berlin wurden von Februar 1996 bis Juni 1999 alle dort vorkommenden verwilderten Katzen erfaßt. Wir untersuchten Alter- und Geschlechtsverteilung, Populationsdichte und -stabilität, Reproduktions- und Mortalitätsraten, Gesundheitsstatus, Territorialverhalten, Ver- wandtschaftsbeziehungen und den Einfluß der Kastration auf das individuelle Verhal- ten der Katzen und die Entwicklung der Population. Insgesamt wurden 75 Tiere in- nerhalb von 42 Monaten beobachtet. Im Untersuchungsgebiet waren gleichzeitig je- weils 25-32 Tiere ansässig, außerdem wurden durchschnittlich 10 Durchzügler pro Jahr registriert. Die ansässigen Katzen lebten in 2 genetisch differenzierten Teilpopu- lationen. Unkastrierte Kater hatten größere Streifgebiete (20-66 ha) als kastrierte Ka- ter, kastrierte und unkastrierte Katzen sowie Jungtiere (0,5-7,5 ha). Die Mortalität der ansässigen Katzen betrug 25 % pro Jahr. Vakante Streifgebiete wurden durch eige- ne Nachkommen aufgefüllt. Die Anzahl unkastrierter adulter Kater im Untersu- chungsgebiet blieb über die gesamte Zeit konstant, Kastration und Tod von Deckka- tern wurde durch Einwanderung fremder Kater kompensiert. Nach Kastration aller weiblicher Katzen einer Teilpopulation sank die Populationsdichte trotz signifikant höherer Zuwanderung fremder Tiere. / In a 45 ha study area of Berlin city all cats were studied between February 1996 and June 1999. We investigated age and sex composition, population density and stabil- ity, rates of reproduction and mortality, health status, territorial behaviour, kinship re- lation, and the influence of neutering on individual behaviour and population devel- opment. Altogether we observed 75 cats within 42 months. 25 to 35 cats lived simul- taneously in the study area, additionally we found 10 transient animals per year on average. The resident cats lived in two genetically distinct subpopulations. Uncas- trated adult males had larger home ranges (20-66 ha) than castrated males, cas- trated and uncastrated females and subadult cats (0,5-7,5 ha). Mortality rate of resi- dent cats was 25 % per year. Vacancies were filled by own kittens. The number of uncastrated adult tomcats was constant throughout the study period, castration and death of stud males were compensated by immigration of unknown tomcats. After the castration of all females in one subpopulation population density declined, even though immigration of unknown cats increased significantly.
79

Distribuição espacial e fatores associados ao contato entre javalis e suínos de subsistência no Rio Grande do Sul / Spatial distribution and factors associated with contact between backyard pigs and feral swine in State of Rio Grande do Sul

Medeiros, Antonio Augusto Rosa January 2016 (has links)
O Javali (Sus scrofa scrofa) é uma espécie com ampla distribuição mundial e presente no Brasil. No Rio Grande do Sul, nos últimos anos, aumentaram os relatos de ataques e prejuízos causados pela presença de javalis asselvajados, sendo seus impactos negativos observados na degradação da vegetação nativa e água de superfície, na predação sobre a fauna e pecuária, e na possibilidade de transmissão de doenças para humanos e animais. A localização destes animais de vida livre e os possíveis fatores associados à sua presença são de extrema importância para a Gestão Ambiental e de Saúde Animal, uma vez que estes animais podem assumir um importante papel na introdução e disseminação de doenças para a pecuária gaúcha. Um estudo foi realizado nos anos de 2012 e 2014 no Estado do Rio Grande do Sul visando identificar possíveis fatores associados à presença destes animais de vida livre junto às propriedades de suínos de subsistência e apresentar uma análise espacial para identificar possíveis aglomerados da presença destes animais no Estado. As propriedades amostradas no estudo foram propriedades de suínos de subsistência, que apresentam uma menor tecnificação e biosseguridade quando comparada com as propriedades comerciais, o que pode facilitar essa interação. Foi utilizada uma amostragem proposital, onde foram selecionadas 640 propriedades em cada ano, primeiramente destinada para comprovar a ausência de atividade do vírus da Peste Suína Clássica nos criatórios do Rio Grande do Sul. Um questionário epidemiológico foi aplicado nas propriedades amostradas a fim de caracterizar e identificar as que apresentam relatos da presença de javalis asselvajados e elencar os possíveis fatores associados a sua presença. De todas as 640 propriedades amostradas, em 63 (9,8%) os proprietários relataram a possível presença de suínos asselvajados. Para análise dos fatores associados, foi utilizado um modelo de regressão de Poisson com variância robusta. No modelo final, os fatores associados à presença de javalis asselvajados foram: ter suínos criados próximos a reservas naturais (RP=2,29; IC 95% 1,10- 4,75), criação extensiva de suínos (RP=2,63; IC 95% 1,59- 4,34), ter criação de híbridos de javalis e suínos (RP=2,37; IC 95%1,09-5,19), criações de javalis na propriedade (RP=3,22; IC 95% 1,21- 8,58) e tamanho da propriedade em Km²(RP=0,54; IC 95% 0,26-1,11). Através da análise espacial foi possível identificar aglomerados de relatos da presença destes animais nas regiões sul e nordeste do Estado. Com esse estudo, espera-se dar auxilio do ponto de vista teórico a gestores públicos na implantação de políticas de saúde animal e de conservação que visem mitigar os possíveis riscos da interface animais de produção e vida selvagem. / The wild boar is a species from Eurasia which is widely distributed, being introduced in several countries, including Brazil, where it is considered an exotic invasive species. Considering the fact that pigs and wild boar belong to the same species and share the same pathogens, they have been regarded a reservoir for various harmful diseases for livestock. It is essential scientific knowledge about these free-living populations interactions with commercial pig farming. There are increasing reports numbers regarding attacks and damage caused by feral pig presence in Rio Grande do Sul. It has been causing negative impacts on native vegetation, wildlife predation, and the likelihood of transmitting diseases to humans and animals. This study aims to identify where feral pigs are in the state and assess factors associated with domestic pigs contact. The study was conducted in 2012 and 2014 using a purposive sampling, intended primarily to demonstrate and document the absence of classical swine fever virus in the farms within a free zone. A total of 640 subsistence farms were sampled throughout the state. An epidemiological questionnaire was applied in these farms to identify attack and/or wild boar existence in the vicinities of the property (response variable). A Poisson regression model was used to determine factors associated with wild boar presence in these farms through the estimates of prevalence ratio (PR) and a scan statistic was used to find possible cluster of the wild boars presence in Rio Grande do Sul state. The variables associated with wild boar presence were farms located near forest reserves (PR=2.29; CI 95% 1,10-4,45), Total farm Area (PR=0.54; CI 95% 0.26-1.11), Farms raising outdoors pigs (PR=2.63; CI 95% 1.59-4.34) and farms raising wild boars (PR=3.22; CI 95%1.21- .8.58) and farms raising hybrid with wild boar and swine (PR=2,37; CI 95% 1,09-5,19). In the Northeast region and the Southern state two clusters were identified and overlapped in each year of study. Factors associated with feral pig presence in backyard pig farms were primarily linked with environmental variables. Properties near forest reserves, indigenous reserves and rural settlements had higher prevalence ratio (PR). This can be explained due to feral animals necessity to find refuge areas for its maintenance and stabilization, which increases contact probability with domestic pigs raised round these areas. It is proposed to support decision makers on animal health implementation policies in order to mitigate contact´s risk between domestic species and wild animals, minimizing pathogens transmission probabilities among them.
80

Användning av skuggsystem hos organisationer med sanktionerade intranätverk

Högström, Anton, Mood, Lisa January 2019 (has links)
Företag och organisationer använder sig ofta av sanktionerade, specialanpassade IT-system för att hantera information och kontrollera sin verksamhet. När anställda frångår policys och riktlinjer kring användningen av dessa system kallas det Shadow IT, eller skuggsystem. Detta innebär att de anställda utvecklar nya rutiner, hård- eller mjukvara eller vänder sig till annan etablerad programvara. Detta arbete innefattar en kvalitativ undersökning där kommunikatörer och informatörer vid Uppsala universitet har intervjuats för en orsaksinventerande studie av skuggsytem i förhållande till universitetets sanktionerade intranät Medarbetarportalen. Orsaker som kunnat fastställas till varför användare frångår rutiner och väljer skuggsystem är bristande reglering, mänskliga faktorer, såsom bekvämlighet och motvilja, brister hos systemets kvalitet samt informationens kvalitet. Vidare orsaker är utvecklingen av mer specifika, bättre egna lösningar i form av olika skuggsystem, samt organisationens struktur och kultur. Då Uppsala universitet påverkas av akademisk frihet och anställdas valmöjligheter i och med detta, saknas tydlig kontroll genom policys och föreskrifter från ledningens sida angående användning.

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