Thesis (Ph. D.)--University of Wisconsin, 1950. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [71-73]).

abstract: Birds have plasma glucose levels that are 1.5-2 times greater than mammals of similar body mass in addition to higher free fatty acid concentrations, both of which would typically impair endothelium-dependent vasodilation if observed in mammals. Endothelium-dependent vasodilation can be stimulated in mammals through the use of acetylcholine (ACh), which primarily acts through nitric oxide (NO) and cyclooxygenase (COX)-mediated pathways, with varying reliance on endothelial-derived hyperpolarizing factors (EDHFs). Very few studies have been conducted on small resistance systemic arteries from birds. The hypothesis was that because birds have naturally high glucose and free fatty acid concentrations, ACh-induced vasodilation of isolated arteries from mourning doves (Zenaida macroura) would be independent of endothelial-derived factors and resistant to high glucose-mediated vascular dysfunction. Small resistance mesenteric and cranial tibial (c. tibial) arteries were pre-constricted to 50% of resting inner diameter with phenyleprine then exposed to increasing doses of ACh (10-9 to 10-5 μM) or the NO donor, sodium nitroprusside (SNP; 10-12 to 10-3 μM). For both vessel beds, ACh-induced vasodilation occurred mainly through the activation of potassium channels, whereas vasodilation of mesenteric arteries additionally occurred through COX. Although arteries from both vessel beds fully dilated with exposure to sodium nitroprusside, ACh-mediated vasodilation was independent of NO. To examine the effect of high glucose on endothelium-dependent vasodilation, ACh dose response curves were conducted following exposure of isolated c. tibial arteries to either a control solution (20mM glucose) or high glucose (30mM). ACh-induced vasodilation was significantly impaired (p = 0.013) when exposed to high glucose, but normalized in subsequent vessels with pre-exposure to the superoxide dismutase mimetic tiron (10 mM). Superoxide concentrations were likewise significantly increased (p = 0.0072) following exposure to high glucose. These findings indicate that dove arteries do not appear to have endogenous mechanisms to counteract the deleterious effects of oxidative stress. Additional studies are required to assess whether endogenous mechanisms exist to protect avian vascular reactivity from systemic hyperglycemia. / Dissertation/Thesis / M.S. Nutrition 2012

Made available in DSpace on 2015-10-06T13:02:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-14. Added 1 bitstream(s) on 2015-10-06T13:19:29Z : No. of bitstreams: 1 000849126.pdf: 1214857 bytes, checksum: a2d47dd516d137071a1aa19d9f8af738 (MD5) / A nucleoproteína (NP) do Vírus da Influenza Aviária (VIA) é um importante alvo antigênico no imunodiagnóstico desta doença, devido à sua baixa variabilidade entre as diferentes estirpes do VIA, resultando em uma elevada reatividade cruzada, e por ser também uma proteína altamente imunogênica para hospedeiros vertebrados. Neste estudo, o gene codificador da NP do VIA foi parcialmente clonado e expresso em Escherichia coli como uma proteína recombinante fusionada ao polipeptídeo SUMO e uma etiqueta de poli-histidina para seu uso no desenvolvimento de um ensaio de ELISA indireto para a detecção de anticorpos específicos contra o VIA. A NP recombinante foi expressada na fração solúvel e foi mais facilmente purificada. Após análise em relação aos seus principais sítios de antigenicidade e caracterização por meio de Western blotting, a NP recombinante foi utilizada como uma preparação antigênica no ELISA indireto para detecção de anticorpos contra o VIA presentes em amostras de soro de galinha. A análise comparativa do teste desenvolvido no presente estudo com um ELISA comercial apresentou valores de 95%, 97% e 96,7% de sensibilidade, especificidade e acurácia, respectivamente e um índice κappa de 0,88. Os resultados permitem concluir que a NP recombinante do VIA desenvolvida neste estudo possui características favoráveis para ser aplicada como antígeno no ELISA indireto, constituindo-se em um método sensível e específico para o imunodiagnóstico da Influenza Aviária em galinhas / The nucleoprotein (NP) of Avian Influenza Virus (AIV) is an important antigenic target for immunodiagnosis of this disease, due to its low variability among different AIV strains, resulting in high cross-reactivity, and the also highly immunogenic for vertebrate hosts. In this study, the gene enconding NP of AIV was cloned and expressed in Escherichia coli as a recombinant protein fused to SUMO polypeptide with a polyhistidine tag and used to develop an indirect ELISA for the detection of AIV-specific antibodies. The recombinant NP was expressed in the soluble fraction and easily purified. After Analysis of the main sites of antigenicity and characterization in Western-Blotting, the recombinant NP was optimized as an antigen preparation for indirect ELISA to detect anti-AIV antibodies in chicken serum samples. The comparative analysis of this ELISA with a commercial ELISA showed values of 95%, 97%, 96.7% of sensitivity, specificity and accuracy, respectively, and an agreement of k=0.88. In conclusion, the results indicated that the recombinant NP of AIV produced in this study is a good source of antigen for indirect ELISA and provides a sensitive and specific method for the immunodiagnosis of Avian Influenza in chickens

Master of Science / Department of Diagnostic Medicine/Pathobiology / Alison Paige Adams / Avian influenza (AI) is a zoonotic disease that has garnered much attention in recent years due to its detrimental effects on poultry, producers and potentially human health. This disease can be extremely fatal to domestic poultry, killing as high as 90-100% of the flock. This virus has the potential to cause devastation to and loss of entire flocks. AI is typically spread between wild fowl and domestic poultry with a zoonotic potential to also affect human health as well as other animals. Its spread also has a massive economic impact due to the decreased amounts of available poultry products to consumers around the world. This report will examine the worldwide history and epidemiology of highly pathogenic avian influenza (HPAI). In the last ninety-two years, there have been five recorded outbreaks of HPAI in the United States (US). Globally, notable outbreaks have occurred in Italy (1997-2001), the Dutch region of Europe (2003), Canada (2004), and more recently, in Asia. Preventative measures will be examined in this report. In particular, biosecurity, quarantine, surveillance, and eradication are some of the most widely recognized and accepted ways to help prevent and control HPAI outbreaks. However, none of these methods are failsafe strategies to completely prevent or control the spread of HPAI. This report will focus on an additional preventative measure - currently available and potential future vaccination programs. There is a global shift toward procuring poultry that are AI-free as well as unvaccinated for AI. This is, in part, due to the limitations of currently available vaccines in completely ridding poultry of this disease. Vaccinations may reduce the amount of virus in infected birds, but this does not prevent birds from becoming infected. When addressing the control and eradication of HPAI, some future challenges include viral mutations, intermingling of domesticated and wild birds, and vaccine development. Because of the current limitations of vaccines and future challenges in controlling the spread of infection, there is no one single solution to this problem. It will require a multi-faceted approach.

abstract: Reproduction is energetically costly and seasonal breeding has evolved to capitalize on predictable increases in food availability. The synchronization of breeding with periods of peak food availability is especially important for small birds, most of which do not store an extensive amount of energy. The annual change in photoperiod is the primary environmental cue regulating reproductive development, but must be integrated with supplementary cues relating to local energetic conditions. Photoperiodic regulation of the reproductive neuroendocrine system is well described in seasonally breeding birds, but the mechanisms that these animals use to integrate supplementary cues remain unclear. I hypothesized that (a) environmental cues that negatively affect energy balance inhibit reproductive development by acting at multiple levels along the reproductive endocrine axis including the hypothalamus (b) that the availability of metabolic fuels conveys alterations in energy balance to the reproductive system. I investigated these hypotheses in male house finches, Haemorhous mexicanus, caught in the wild and brought into captivity. I first experimentally reduced body condition through food restriction and found that gonadal development and function are inhibited and these changes are associated with changes in hypothalamic gonadotropin-releasing hormone (GnRH). I then investigated this neuroendocrine integration and found that finches maintain reproductive flexibility through modifying the release of accumulated GnRH stores in response to energetic conditions. Lastly, I investigated the role of metabolic fuels in coordinating reproductive responses under two different models of negative energy balance, decreased energy intake (food restriction) and increased energy expenditure (high temperatures). Exposure to high temperatures lowered body condition and reduced food intake. Reproductive development was inhibited under both energy challenges, and occurred with decreased gonadal gene expression of enzymes involved in steroid synthesis. Minor changes in fuel utilization occurred under food restriction but not high temperatures. My results support the hypothesis that negative energy balance inhibits reproductive development through multilevel effects on the hypothalamus and gonads. These studies are among the first to demonstrate a negative effect of high temperatures on reproductive development in a wild bird. Overall, the above findings provide important foundations for investigations into adaptive responses of breeding in energetically variable environments. / Dissertation/Thesis / Doctoral Dissertation Biology 2018

Foram realizados dois experimentos com o objetivo de determinar a concentração de zinco e manganês na dieta de frangos de corte sobreas características de desempenho, disponibilidade e mineralização óssea, além da comparação de métodos para quantificar o grau de mineralização óssea. Em cada um dos experimentos foram distribuídos 320 pintinhos machos em delineamento experimental inteiramente casualizado, com oito tratamentos e cinco repetições de oito aves cada. O diferencial existente entre o experimento um e dois está relacionado com o micromineral avaliado, sendo o zinco e o manganês, respectivamente. No experimento um, uma dieta foi sem inclusão de zincoe os níveis de inclusão de sulfato de zinco foram de 60 e 100mg/kg e de zinco metionina de 20, 40, 60, 80 e 100 mg/kg. No experimento dois, uma dieta foi sem inclusão de manganês e os níveis de inclusão de sulfato de manganês foram de 65 e 105 mg/kg e de manganês metionina de 25, 45, 65, 85 e 105 mg/kg. Em ambos experimentos, para determinar a disponibilidade, comparou-se uma dieta sem adição do micromineral com outras dietas com adição do micromineral, na fonte orgânica e inorgânica. Para determinar a exigência, somente os níveis dos microminerais na fonte orgânica foram comparados entre si. Os microminerais estudados (zinco e manganês) não interferiram no desempenho das aves independente do nível e fonte em que foram utilizados. Aos 38 dias, o zinco (60 e 100 mg/kg) e o manganês (105 mg/kg) orgânico foram excretados em menor quantidade em comparação com os mesmos minerais na fonte inorgânica. Sugerindo assim, uma melhor absorção do micromineral orgânico. Independente da fonte e nível utilizado, os microminerais estudados não interferiram nas características ósseas avaliadas (peso, comprimento e largura da tíbia, peso do tarso- metatarso e peso das falanges). Em ambos estudos, o grau de mineralização óssea aumentou conforme elevou-se a concentração de zinco ou de manganês na dieta, independente da fonte em que estes microminerais foram estudados. O método mais adequado para determinação do teor de zinco e de manganês é através da utilização de tíbias. / Two experiments were conducted with the objective of determining the concentration of zinc and manganese in the diet of poultry, the experiments were done on the performance, availability and bone mineralization, besides the comparison of methods to quantify the degree of bone mineralization. In each experiment 320 male chicks were distributed in a totally randomized and experimental design, with eight treatments and five replicates of eight birds each. The existing differential between experiment one and experiment two is related to the evaluated micro mineral (trace elements), beingzinc and manganese respectively. In experiment one, one diet did not include zinc and the other diets included levels of zinc sulfate of 60 and 100 mg/kg, and of zinc methionineof 20, 40, 60, 80 and 100 mg/kg. In experiment two, one diet did not include manganese and the other diets included levels of manganese sulfate of 65 and 105 mg/kg, and of manganese methionine of 25, 45, 64, 85 and 105 mg/kg. In both experiments, to determine the availability, a diet without the addition of micro mineral was compared to other diets with the addition of the micro mineral in the organic and inorganic sources. To determine the requirement, only the levels of micro mineral in the organic source were compared among themselves. The studied micro mineral did not interfere on the poultry performance regardless thelevel and source in which they were used. At 38 days, the quantities of zinc (60 and 100 mg/kg) and manganese (105 mg/kg) excreted from an organic source were lower in comparison to the same minerals in an inorganic source. Thus suggesting a better absorption of the organic micro mineral. Regardless the used source and level, the studied micro minerals (zinc and manganese) did not interfere in the evaluated bone characteristics (weight, length and width of the tibia, the weight of the tarsus - metatarsus and the weight of the phalanges). In both studies the degree of bone mineralization increased in accordance with the increased concentration of zinc and manganese in the diet, regardless the source in which those micro mineralswere studied. The most appropriate method for determining the zinc and the manganese content is through the use of tibia.

Orientador: Wanderley Dias da Silveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T07:50:57Z (GMT). No. of bitstreams: 1 Silveira_Flavio_M.pdf: 7271586 bytes, checksum: 61c4ca3b97e4b7443d820cd714394fa8 (MD5) Previous issue date: 2013 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Mestrado / Microbiologia / Mestre em Genética e Biologia Molecular

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