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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.
211

Investigating host genetics and the role of selection for increased resistance to bovine tuberculosis in dairy cattle

Raphaka, Kethusegile January 2018 (has links)
The significant social and economic losses as a result of bovine tuberculosis (bTB) present a continuous challenge to cattle industries in the United Kingdom (UK) and worldwide. Furthermore, as a zoonotic disease, bTB may pose a threat to humans. The potential transmission of bTB in cattle, estimated by the basic reproductive ratio (R0) was found to range between 1.0 and 1.9 in previous studies. In the UK, there has been an overall increase in bTB incidence in the last two decades despite national control and eradication programmes spanning over five decades. Such programmes mainly consist of surveillance based on the administration of skin tests and culling of animals reacting positive to these tests. Animal mobility restrictions are implemented in this case. At the same time, several studies have demonstrated that there is significant host genetic variation in individual cattle susceptibility to bTB, making the disease amenable to improvement with genetic or genomic selection. In addition, genomic analyses enhance the understanding of genetic mechanisms underlying the disease and its dynamics. The overall aim of this PhD thesis was to address existing scientific research gaps on the genetics of bTB resistance in dairy cattle. The following specific objectives were set: 1) to identify genomic regions underlying susceptibility to bTB using novel trait definitions, 2) to quantify the impact of long-term genetic selection for increased resistance to bTB on disease prevalence and dynamics and 3) to determine the consequences of genetically selecting for increased resistance to bTB on other economically important traits in dairy cattle. Genome-wide association studies (GWAS), regional heritability mapping (RHM) and chromosomal association analyses were applied in order to identify genomic regions associated with bTB (objective 1). Phenotypes comprised de-regressed estimated breeding values of 804 Holstein-Friesian sires obtain from the UK national genetic evaluation for bTB. Phenotypes pertained to three bTB trait definitions: i) positive reactors to the skin test with positive post-mortem examination results (phenotype 1); ii) positive reactors to the skin test regardless of post-mortem examination results (phenotype 2) and iii) as in (ii) plus non-reactors and inconclusive reactors to the skin test with positive post-mortem examination results (phenotype 3). In all cases, non-reactors without a subsequent positive post-mortem were considered to be healthy animals with regards to bTB. Genotypes based on a 50K SNP DNA array were available and a total of 34,874 SNPs remained after quality control. The estimated polygenic heritability for susceptibility to bTB was 0.26, 0.37 and 0.34 for phenotypes 1, 2 and 3, respectively. GWAS identified a putative SNP on Bos taurus autosomes (BTA) 2 associated with phenotype 1, and another on BTA 23 associated with phenotype 2. Genomic regions encompassing these SNPs were found to harbour potentially relevant annotated genes. RHM confirmed the effect of these genomic regions and identified new regions on BTA 18 for phenotype 1 and BTA 3 for phenotypes 2 and 3. Heritabilities of the genomic regions ranged between 0.05 and 0.08 across the three phenotypes. Chromosome association analysis indicated a major role of BTA 23 on susceptibility to bTB. A stochastic genetic epidemiological model based on four main disease states, namely susceptible (S), exposed (E), infectious (I) and test-sensitive (T), was developed to address objective 2. Effects of selection for increased resistance to bTB were investigated in a closed, genetically heterogeneous simulated population whose structure reflected the UK national dairy herd. Disease dynamics reflected real bTB data from the UK national genetic evaluation. The proposed genetic epidemiological model was implemented to simulate breakdowns under both absence and presence of selection. Genetic selection was simulated over 20 generations in 50 replicates, while exploring various selection intensities reflecting selection of the 10, 25, 50, 70 and 100% (no selection scenario) most resistant sires. Results indicated that selection significantly reduced the average underlying susceptibility across generations. The risk of breakdown was reduced by half after 4 and 6 generations for high selection intensities (10 or 25% of sires selected) and after 9 and 15 generations for low selection intensities (50 or 70% of sires selected). The average percentage of secondary cases was reduced to less than 1% in 4 and 5 generations for high selection intensities, and in 7 and 11 generations for low selection intensities. The reduction in the number of secondary cases across generations could also be indicative of the possible impact of genetic selection on the basic reproductive ratio (R0) which is defined as the number of secondary cases that results from an infectious individual in a naive population. Genetic selection also reduced severity and duration of breakdowns across generations. Finally, with regards to objective 3, a stochastic simulation was used to investigate the long-term effects of selection for resistance to bTB on other economically important traits in the UK dairy selection programme. Selection was simulated in a genetically heterogeneous population across 10 generations in 50 replicates. Animal genetic values for bTB and other traits were simulated based on variance and genetic correlation estimates obtained from literature. Independent culling levels selection of sires was applied in every generation whereby selection was first based on increasing resistance to bTB, then improving either an overall index, milk fat yield (FY) or milk protein yield (PY). This mimics real life practices regarding the newly released national genetic evaluations for bTB resistance. The overall index comprised several traits of interest such as milk yield (MY), FY, PY, feet and legs (FL), mammary (MAM), milk somatic cell count (SCC), calving interval (CI), non-return to service at 56 days (NR56) and lifespan (LS). A fertility index (FI) consisting of CI and NR56 was also considered in the analyses. Regarding bTB, different levels of selection intensities were explored corresponding to selection of the 10, 25, 50, 70 and 100% (no selection) most resistant sires. Two levels of selection intensity on the overall index, FY or PY were considered corresponding to selecting the best 5 and 10% of sires that were left after first selecting for bTB resistance. Results indicated that selection for increased bTB resistance would generally not have far-reaching consequences on other important traits. As expected, susceptibility to bTB declined with time and increasing selection intensity. Trends for all production traits (MY, FY and PY) in the present study were affected by selection for increased bTB resistance because of their significant genetic correlations with bTB. However, body conformation traits (FL and MAM) were not affected by selection for increased bTB resistance due to zero correlation assumed between these traits and bTB in the present study. Selection on bTB hampered improvement of SCC but enhanced LS because it was correlated unfavourably with SCC but favourably with LS. In all selection scenarios, the overall index improved and was generally not affected by selection for bTB resistance. Similarly, the FI was not affected by selection on bTB in all cases. However, secondary selection on production traits only (FY or PY) led to a decline in FI. Results presented in this thesis add insight into the genetic architecture of bTB and offer a prediction of potential effects of genetic selection for increased resistance to bTB in dairy cattle. The genomic regions and candidate genes identified to be associated with susceptibility to bTB will assist to further elucidate pathways critical to cattle susceptibility to bTB. / Consistent with previous studies of other populations and trait definitions, results from genomic association analyses suggest that susceptibility of cattle to bTB is heritable and likely a polygenic trait, amenable to improvement by genetic and/or genomic selection. Embarking on routine selection for resistance to bTB will reduce future bTB prevalence and severity of breakdowns across selection generations, as manifested by results of this thesis. The results also highlight the importance of considering selection as a complementary strategy to existing interventions. This has the potential to accelerate control and ultimate eradication of bTB. This strategy could assist the UK to achieve the national goal of being officially bTB free by 2038. Furthermore, as indicated by results of this thesis, selection against bTB in the national breeding programme will not adversely affect other economically important traits. Assimilation of bTB into the overall index will better manage possible antagonistic correlations between bTB susceptibility and some of the other traits.
212

Produção e aplicação de hidrolisado de proteínas do soro de queijo bovino no preparado de suplemento nutricional : minimização da sarcopenia em ratos idosos /

Marques, Daniela Parreira. January 2009 (has links)
Orientador: Rubens Monti / Banca: Thais Borges Cesar / Banca: João Atílio Jorge / Banca: Rosa dos Prazeres Melo Furriel Inocentes / Banca: Reinaldo Marchetto / Resumo: Os hidrolisados de proteínas do soro de queijo vêm sendo amplamente utilizados para diversos fins. Dependendo das enzimas utilizadas e meio de reação, podemos obter hidrolisados com diferentes características. O intuito do presente trabalho foi hidrolisar as proteínas do soro de queijo bovino de diferentes maneiras, variando-se a temperatura de reação e modo de adição das enzimas, a fim de se obter hidrolisados com diferentes graus de hidrólise para posterior aplicação em ensaios animais. Os hidrolisados escolhidos para aplicação nos ensaios biológicos foram obtidos pela ação das enzimas pepsina, tripsina, quimotripsina e carboxipeptidase a 50ºC. Dois hidrolisados diferentes foram preparados: um com maior quantidade de pequenos peptídeos (oligo, di e tripeptídeos) e outro com maior quantidade de aminoácidos livres. O soro sem hidrólise também foi utilizado como suplementação para um outro grupo de animais. A intenção foi testar os dois diferentes hidrolisados e o soro sem hidrólise como suplemento para ratos idosos, visando a minimização da sarcopenia. Diversos estudos apontam que fórmulas contendo oligopeptídeos, especialmente di- e tripeptídeos, possuem maior valor nutricional do que uma mistura equivalente de aminoácidos livres ou proteínas intactas. Tomando-se como base essa informação, delineou-se a pesquisa esperando-se que, o grupo suplementado com as proteínas parcialmente hidrolisadas obtivesse um melhor desempenho na minimização da sarcopenia. Todos os 3 grupos suplementados obtiveram aumento na massa muscular e óssea diferindo significativamente em relação ao controle (não suplementado) porem, o que apresentou efeitos mais positivos na minimização da sarcopenia foi realmente o grupo suplementado por proteínas parcialmente hidrolisadas. Paralelamente a esse estudo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The cheese whey hydrolysates have been widely used for various purposes. Depending on the enzymes used and the reaction medium, we can obtain hydrolysates with different characteristics. The purpose of this study was to hydrolyze bovine cheese whey proteins in different ways, varying the temperature of reaction and enzyme addition, in order to obtain hydrolysates with different degrees of hydrolysis for application in animal tests. The hydrolysates chosen for application in biological assays were obtained by the action of enzymes pepsin, trypsin, chymotrypsin and carboxypeptidase at 50°C. Two different hydrolysates were prepared: one with a larger amount of small peptides (oligo-, di-and tripeptides) and another with larger amount of free amino acids. Serum without hydrolysis was also used as a supplement to another group of animals. The intention was to test the two different hydrolysates and whey without hydrolysis as a supplement to old age rats in order to minimize the sarcopenia. Several studies indicate that formulas containing oligopeptides, especially di-and tripeptides, have higher nutritional value than an equivalent mixture of free amino acids or intact proteins. Taking this information as a basis, the research was then outlined expecting that the group supplemented with partially hydrolyzed protein could obtain a better performance in reducing the sarcopenia. The all 3 supplemented groups showed increase in muscle mass and bone and differ significantly from control (not supplemented). However, the group who presented the most positive effects in reducing the sarcopenia was actually the group supplemented with partially hydrolyzed protein. In parallel with this study, in sandwich PhD, the attainment of immobilized pepsin and trypsin (derivatives) in solid support, stable was studied, for further application to obtain... (Complete abstract click electronic access below) / Doutor
213

Novel aspects of the activity and function of xanthine oxidase

Millar, Timothy Marc January 1999 (has links)
No description available.
214

Fatores homólogos aos fatores de crescimento fibroblásticos são expressos em folículos antrais e corpos lúteos bovinos

Costa, Isabela Bazzo da [UNESP] 30 July 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-30Bitstream added on 2014-06-13T20:26:15Z : No. of bitstreams: 1 costa_ib_dr_botfmvz.pdf: 543721 bytes, checksum: 907dc454dbac989d147fcfadba4c9482 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Vários membros da família dos fatores de crescimento fibroblásticos (FGFs) estão envolvidos na regulação da função ovariana. No entanto, uma pequena subfamília dos FGFs conhecida como Fatores Homólogos aos Fatores de Crescimento Fibroblásticos (FHFs) as quais são proteínas não secretadas, estão altamente expressas no desenvolvimento e maturação do sistema nervoso. Sabe-se que nos neurônios os FHFs se ligam a proteínas mediadoras da cascata MAP quinase e a canais de sódio voltagem-dependentes, mas suas funções fisiológicas precisam ser melhor elucidadas. Ainda não foi investigada a expressão dos FHFs em tecidos reprodutivos bovinos. O objetivo deste estudo foi avaliar a expressão do RNAm dos FHFs (FHF-1 a 4) e da proteína do FHF-2, em células da granulosa (CG), células da teca (CT) e corpos lúteos (CL) bovinos, e ainda determinar se a expressão do RNAm dos FHFs em CG cultivadas é regulada na presença de FSH e IGF-1. Para tanto, CG, CT e CL foram obtidos de ovários de abatedouro para a extração do RNA total. Dez CL de cada estágio (estágio 1: corpo hemorrágico; estágio 2: CL em desenvolvimento; estágio 3: CL maduro; estágio 4: CL em regressão) foram selecionados para a extração do RNA total. CG e CT foram dissecadas individualmente de folículos antrais >5mm e submetidas ao protocolo de extração de RNA total. Os folículos foram agrupados de acordo com o diâmetro (pequeno: 5-7mm; médio: 8-10mm; grande: >10mm) e estágio de desenvolvimento (saudáveis: >1; transicional: 0,01-1; atrésicos: <0,01). As concentrações de estradiol e progesterona foram mensuradas no fluido folicular por RIA. Para investigar a regulação da expressão do RNAm dos FHFs pelo FSH e IGF-1, CG de folículos de 2 a 5mm foram cultivadas em meio suplementado com FSH (0, 0,1, 1, 10 ou 100ng/ml) ou IGF-1 (0, 5, 10, 50 ou 100 ng/ml). A expressão do RNAm dos FHFs foi examinada... / Several members of the fibroblast growth factor (FGF) family are involved in the regulation of ovarian function. However, the small FGF subfamily encodes non-secreted proteins otherwise known as FGF homologous factors (FHF) that are mostly expressed in the developing and mature nervous system. It is known that within neurons, FHFs bind to MAPK scaffold proteins and to voltage-gated sodium channels, but their physiological functions need to be elucidated. FHFs have not been investigated in bovine reproductive tissues. The small FGF subfamily that encodes non-secreted proteins otherwise known as FGF homologous factors (FHFs) has not been investigated in bovine reproductive tissues. The aims of this study were to assess FHFs (1-4) mRNA and protein (FHF-2) expression in granulosa (GC), theca cells (TC) and corpora lutea (CL) from bovine ovaries and to determine if expression in GC is regulated by FSH and IGF-1. Antral follicles and corpora lutea were dissected from bovine ovaries obtained at a local abattoir for total RNA extraction. Ten CL from each of four developmental stages (stage 1, corpus hemorragicum; 2, developing CL; 3, mature CL; and 4, regressing CL) were selected for RNA extraction. TC and GC cells were dissected from individual antral follicles larger than 5mm and submitted to total RNA extraction. Follicles were grouped according to size (small: 5-7mm; medium: 8-10mm; large: bigger than 10mm) and health status based on the ratio between concentrations of estradiol and progesterone measured by RIA in the follicular fluid (healthy: higher than 1; transitional: 0.01-1; atretic: lower than 0.01). To investigate regulation of FHFs mRNA by FSH and IGF-1, GC from small follicles (2-5 mm) were placed into serum-free medium supplemented with insulin and bovine FSH (0, 0.1, 1, 10 or 100 ng/ml) or IGF-1 (0, 5, 10, 50 or 100 ng/ml). FHFs gene expression was... (Complete abstract click electronic access below)
215

Current and future strategies of bovine respiratory disease diagnostics and treatments

Miller, Shelby Lynn January 1900 (has links)
Master of Science / Department of Diagnostic Medicine/Pathobiology / Alison P. Adams / Bovine respiratory disease (BRD) is the most common and costly disease affecting cattle in the world today. The disease was first described in the late 1800s and is one of the most extensively studied diseases of livestock. BRD accounts for 65 - 80% of the morbidity and 45 - 75% of the mortality in some feedlots. Outbreaks typically occur around 10 days after transportation with the majority of deaths occurring within the first 45 days of arrival. Bacterial pathogens, physiologic stressors, and concurrent viral infections are all important factors causing BRD; other factors include seasonality, heritability, and breed tolerance. Diagnostic and treatment measures are continually being critiqued and researched. Even with continued research and the administration of antibiotics, BRD still continues to be a problem for the beef industry. Remote early detection and previous calf history are two resources that can help feedlots diagnose the disease earlier, or prevent it entirely. Feeding behavior and physical exams of the calves can also aid in early detection. New antibiotics and treatment methods have been developed, but the BRD problem still exists. Since the disease is most problematic in feedlot cattle, treatment of a large number of cattle in this setting can be costly, and often, performance and carcass traits are also affected. New preventative measures will be crucial to the industry with the continued problems and consequences of BRD. Improved treatment options and enhanced diagnostic tools will also be imperative for the control and treatment of BRD in the future.
216

Estudo microbiológico em carcaças bovinas e influência da refrigeração sobre a microbiota contaminante

Fontoura, Cristianne Lino [UNESP] 28 September 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-09-28Bitstream added on 2014-06-13T20:35:30Z : No. of bitstreams: 1 fontoura_cl_me_jabo.pdf: 235669 bytes, checksum: fca01c25cc9edf7cab4df726d6520e4f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A carne e seus derivados apresentam grande valor na alimentação humana e se enquadram entre os alimentos de origem animal mais perecíveis, principalmente pela sua variedade e riqueza nutricional. Constituem-se em importante veículo de agentes zoonóticos e especial meio de cultura para o desenvolvimento e multiplicação de uma ampla gama de microrganismos. O presente trabalho teve por finalidade avaliar a presença de alguns microrganismos potencialmente patogênicos (Salmonella sp., Staphylococcus aureus e Listeria sp.) e alguns indicadores como microrganismos psicrotróficos, mesófilos e coliformes na superfície de meias carcaças bovinas logo após a lavagem e avaliar a influência da refrigeração na população microbiana (de indicadores e Staphylococcus aureus). As amostras foram obtidas em um matadouro frigorífico localizado no interior do Estado de São Paulo, submetido a controle higiênico-sanitário permanente e com comércio no mercado interno e externo. No total foram analisadas 80 amostras (suabes) de regiões da superfície externa da carcaça (coxão, lombo e ponta-de-agulha) sendo 40 logo após a lavagem e 40 após 24 horas sob refrigeração. Na grande maioria das amostras as populações de microrganismos heterotróficos mesófilos estiveram entre 1,0 e 1,0 x 102 UFC/cm2, indicando eficiência nos cuidados higiênico-sanitários durante as operações de abate. Para os microrganismos psicrotróficos encontrou-se populações inferiores a 2,0 x 103 UFC/cm2, o que pode permitir maior vida-de-prateleira ao produto e para Staphylococcus sp. as populações foram inferiores a 1,0 x 103 UFC/cm2, não tendo sido encontrado nenhuma cepa da espécie Staphylococcus aureus. Os valores médios... / The meat as well its derivatives show great value in human aliments of animal origin principally because of its variety and nutritional wealth. It constitutes an important vehicle of zoonotic agents and a special means of culture for the development and multiplication of one large gamut of microorganisms. The present work had the goal to evaluate the presence of some microorganisms potentially pathogenic (Salmonella sp, Staphylococcus aureus and Listeria sp) and some indicators such as psychrotrophic, mesophilic and coliforms in the surface of half the bovine carcass after it is washed and evaluated as to the influence of storage by refrigeration of the microbial population (of indicators and Staphylococcus aureus). The samples were obtained in a slaughterhouse cooler located in the inner city of Sao Paulo, using constant sanitary hygienic control and doing business in the internal market as well to the external market. In total, 80 samples were analyzed (swab) of regions in the external surface of the carcasses (rump, loin and rib), results being 40 as soon as it was washed and 40 after 24 hours under refrigeration. In the large majority of samples the population of microorganism mesophilic were between 1,0 e 1,0 x 102 UFC/cm2, indicating efficiency in the care of sanitary hygene during the operations of slaughter. For the microorganisms populations psychrotrophic were found to be below 2,0 x 103 UFC/cm2, permitting longer shelf life of the product. For Staphylococcus sp, the populations were lowered to 1,0 x 103 UFC/cm2, and no species of cepa Staphylococcus aureus was found. The medium values for the populations of mesophilic, psychrotrophic and Staphylococcus sp. respectively were... (Complete abstract click electronic access below)
217

Tipificação citológica do líquido amniótico no momento do parto de bezerros Nelore oriundos de produção In Vitro, transferência de embrião e inseminação artificial

Moya, Carla Fredrichsen [UNESP] 20 February 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-20Bitstream added on 2014-06-13T19:38:35Z : No. of bitstreams: 1 moya_cf_me_botfmvz.pdf: 156959 bytes, checksum: 8445a2c6b5b162a42c66e3322c1bbd52 (MD5) / A proposta do presente estudo foi descrever as diferenças no padrão morfológico das células do fluido amniótico, no momento do parto. Comparando os resultados obtidos de bezerros nelores oriundos de produção in vitro, transferência de embriões e inseminação artificial. Utilizaram-se 60 animais, divididos em Grupo 01: vinte vacas inovuladas com embriões Nelore produzidos in vitro (PIV) a partir de colheita de oócitos por aspiração folicular de doadoras, Grupo 02: vinte vacas gestando bezerros nelores originados de inovulações de embriões oriundos de doadoras superovuladas pelo método convencional, e Grupo 03: vinte vacas nelores PO gestando bezerros oriundos de inseminação artificial (controle). Próximo ao parto as vacas foram transferidas para piquete maternidade com acompanhamento dos partos. Durante a fase de expulsão e após a ruptura do alantocórion realizou-se a punção do âmnion para colheita de 20mL de liquido, que foi depositado em tubo plástico e congelado em freezer. Para a classificação celular as amostras, pós-descongelação, foram centrifugadas na Citocentrifuga (Revan Centrifuga Ciclo Cito) a 4000rpm durante seis minutos e empregou-se a técnica de coloração Hematoxilina-Shorr. Ao final deste procedimento, as lâminas citológicas foram montadas com lamínulas empregando Bálsamo do Canadá e posteriormente (após o período de secagem) observadas em microscópio óptico com aumentos de 200x e 400x para visualização das características morfológicas e tintoriais das células epiteliais do feto. Para avaliação da maturidade epidérmica utilizou-se a técnica de coloração de Sulfato Azul do Nilo bem como a porcentagem de células queratinizadas (coloração Hematoxilina-Shorr). As células basais e parabasais não foram encontradas nas lâminas citológicas das amostras de líquido amniótico analisadas... / The aim of the present study was to describe the differences in the cytological pattern of the amniotic fluid, at the moment of delivery, comparing the data from Nelore calves obtained by in vitro production, embryo transfer and artificial insemination. Sixty (n=60) Nelore cows were divided in group 01: Twenty cows (n=20) pregnant with Nelore calves obtained by in vitro production (IVP) after follicular aspiration; group 02: Twenty cows (n=20) pregnant with Nelore calves obtained by superovulation of embryo donors (ET); group 03: Twenty Nelore cows (n=20) pregnant of calves obtained by artificial insemination (AI; control). Near to the labor, the cows were transferred to a maternal paddock, permitting delivery observation. During the expulsion phase, after the rupture of the alantochorion the amnion was punctured and 20ml of fluid were collected in a plastic device and frozen. The samples, after being thawed, were centrifuged at 4000 rpm, during 06 minutes the Hematoxilin-Shorr stain was applied, after this, the glass slides were covered with Canadian balsame and analyzed in optical microscopy. To the evaluation of the epidermal maturity were used the Blue Nile Sulfate stain, as well the percent of keratinizaded cells observed in the Hematoxilin-Shorr stain. The basal and parabasal cells were not found on the slides of the amniotic fluid samples analyzed. The small intermediate cells (CIP) had its shape as an oval or polygonal form with large cytoplasm and central nucleus. The large intermediate cell (CIG) showed a central nucleus and a bigger nucleus-cytoplasm relation compared to the superficial cells. These were the largest cells found. They showed keratinization with angular edges, having both a picnotic nucleus (CSN) and no nucleus at all. (CSA). The technique of Blue Nile Sulfate stain did not showed satisfactory for the evaluation of the fetal maturity, in spite of some records... (Complete abstract click electronic access below)
218

Estratégias de vacinação contra doenças da reprodução nas taxas de prenhez de vacas em lactação /

Pereira, Marcos Henrique Colombo, 1986. January 2012 (has links)
Orientador: José Luiz Moraes Vasconcelos / Banca: Amauri Alcindo Alfieri / Banca: Marcos Bryan Heinemann / Resumo: O objetivo deste estudo foi avaliar se vacinação contra doenças da reprodução melhora o desempenho reprodutivo de vacas de leite em lactação. Foram realizados quatro experimentos. O experimento 01 foi realizado em 38 fazendas que não utilizavam vacina contra Rinotraqueíte Infecciosa Bovina (IBR), Diarreia Viral Bovina (BVD) e Leptospirose, foram utilizadas 853 vacas Girolando que foram vacinadas (grupo tratado) ou não (grupo controle) no dia -11 (inicio do protocolo de IATF). A segunda dose da vacina foi realizada no dia 30 (diagnóstico de gestação). A vacina que foi utilizada é composta de amostras atenuadas quimicamente alteradas do vírus da IBR associada a amostras citopáticas e não citopáticas do vírus da BVD e culturas inativadas contra cinco sorotipos da Leptospira spp (canicola, grippotyphosa, hardjo, icterohaemorrhagiae e pomona). O experimento 02 foi realizado em 28 fazendas que não utilizavam vacina contra IBR, BVD e Leptospirose, foram utilizadas 287 vacas Girolando que foram pré vacinadas (grupo tratado) ou não (grupo controle) entre os dias -41 a -32, e a segunda dose da vacina foi realizada no dia -11 (inicio do protocolo de IATF). O experimento 03 foi realizado em 17 fazendas que não utilizavam vacina contra IBR/BVDV e Leptospirose, foram utilizadas 1680 vacas holandesas, sendo que vacas com mais de 28 dias em lactação foram vacinadas (grupo tratado) ou não (grupo controle), e a segunda dose da vacina foi realizada 14 dias após a primeira dose. As inseminações foram realizadas entre 15 a 135 dias após a segunda dose da vacina e as perdas de gestação foram avaliadas até 60 dias após a última IA. O experimento 04 foi realizado em 15 fazendas que utilizavam vacina contra IBR, BVD e Leptospirose, foram utilizadas 820 vacas Girolando que foram re-vacinadas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate the effect of vaccination against reproductive diseases on the reproductive performance of lactating dairy cows. The experiment 01 was performed in 38 farms that did not utilize vaccine against IBR/BVD and Leptospirosis, 853 Girolando cows were vaccinated (treated group) or not (control group) on day -11 (beginning of the TAI protocol). The second dose of vaccine was held on day 30 (preganancy diagnosis). The vaccine that was used consists of chemically altered live samples of the IBR virus associated with samples of cytpathic and non cytopathic BVD virus and inactivated cultures against five serotypes of Leptospira spp. (canicola, grippotyphosa, hardjo, icterohaemorrhagiae e pomona). The experiment 02 was performed in 28 farms that did not utilize vaccine against IBR/BVD and Leptospirosis, 287 Girolando cows were pre - vaccinated (treated group) or not (control group), between the days -41 to - 31, the second dose of vaccine was held on day -11 (beginning of the TAI protocol). The experiment 03 was performed in 17 farms that did not utilize vaccine against IBR/BVD and Leptospirosis, 1680 Holstein cows were used in this study, cows with more than 28 days in milk were vaccinated (treated group) or not (control group), the second dose of vaccine was performed 14 days after de first dose. The AI were performed between 15 and 135 days after the second vaccine dose and the pregnancy loss at 60 days after the last AI. The experiment 04 was performed in 15 farms that utilize vaccine against IBR/BVD and Leptospirosis, 820 Girolando cows were vaccinated (treated group) or not (control group) on day -11 (beginning of the TAI protocol). The pregnancy rate was evaluated in the experiments 1, 2 and 4 at 30 and 71 days after TAI, in experiment 03 the pregnancy...(Complete abstract click electronic access below) / Mestre
219

Composição bioquímica e hormonal do líquido ammniotico de fetos bovinos oriundos de inseminação artificial(IA), transferência de embriões(TE) e produção in vitro(PIV) /

Piagentini, Marcelo. January 2008 (has links)
Orientador: Nereu Carlos Prestes / Banca: Eunice Oba / Banca: Regina Kiomi Takahira / Banca: Daniel Bartceli de Souza / Banca: Gilson Hélio Toniollo / Resumo: O presente trabalho teve por objetivo comparar a composição bioquímica e as concentrações de testosterona e progesterona no líquido amniótico de fetos bovino da raça Nelore produzidos por fecundação in vivo, fecundação in vivo com transferência de embrião (TE) e produção in vitro (PIV). Os problemas fetais observados ao momento do parto e pós-parto imediato em animais oriundos de PIV e a escassez de pesquisas que determinem a composição do líquido amniótico associada aos três sistemas de produção embrionária permitiram o desenvolvimento deste trabalho. Utilizaram-se 60 animais divididos em: grupo 01 - vacas Nelore gestando bezerros oriundos de inseminação artificial (IA) (n=20); grupo 02 - receptoras gestando bezerros Nelore provenientes de inovulações de embriões oriundos de doadoras superovuladas pelo método convencional (n=20); grupo 03 - receptoras de embriões gestando bezerros Nelore originados de inovulações de embriões oriundos de doadoras pelo método de aspiração folicular (n=20). No momento do parto, após a visualização das bolsas, colheram-se 15mL de líquido amniótico por punção da bolsa com agulha e seringa adequadas. As amostras foram processadas e analisadas no serviço de laboratório clínico do Departamento de Clínica Veterinária da FMVZ/UNESP de Botucatu-SP e no Laboratório de Endocrinologia do departamento de Reprodução Animal e Radiologia Veterinária. Para análise bioquímica foram utilizados Kits comerciais seguindo a técnica recomendada pelo fabricante. A dosagem hormonal de progesterona (P4) e testosterona (T) foi determinada por meio de radioimunoensaio em fase sólida com a leitura realizada em contador Gama Count Cobra II. Os dados obtidos na avaliação bioquímica e no perfil hormonal foram submetidos à análise de variância (ANOVA) e, uma vez demonstrada diferença estatística por 22 esse teste aplicou-se o Método de Tukey, com 5% de nível de significância. / Abstract: The present work had for objective to compare the biochemical composition and the concentrations of testosterone and progesterone in the amniotic fluid of fetuses of the Nelore cows produced by in vivo fecundation, in vivo fecundation at embryo transfer (ET) and in vitro production (IVP). The fetal problems observed at the delivery moment and at the immediate post-partum in animals originating from IVP and the shortage of researches that determine the composition of the amniotic fluid associated to the three systems of embryonic production allowed the development of this work, adding results to the studies that are being done by other researchers with the placenta of IVP animals. Sixty animals were used divided into 3 groups: Group 1 - Nelore cows pregnant with calves conceived by artificial insemination (AI) (n=20); Group 2 - receptor cows pregnant with Nelore calves provement from superovulation of embryo donors (n=20); Group 3 - receptor cows pregnant with Nelore calves obtained by in vitro production after follicular aspiration (n=20). At the delivery moment, after the visualization of the sacs, 15mL of amniotic liquid were collected by puncture. The samples were processed and analyzed in the service of clinical laboratory of the Department of Veterinary Clinic of FMVZ/UNESP of Botucatu-SP and in the Laboratory of Endocrinology of the department of Animal Reproduction and Veterinary Radiology. For biochemical analysis commercial kits were used following the technique recommended by the manufacturer. The hormonal determinaton of progesterone (P4) and testosterone (T) was performed through radioimmunossay (RIA) in solid phase with the reading accomplished in accountant Gama Count Collects II. The data obtained in the biochemical evaluation and in the hormonal profile were submitted to the variance analysis (ANOVA) and, once demonstrated a statistic difference by that method the Tukey test was applied, with a 24 5% of level significancy. / Doutor
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Etude de la régulation transcriptionnelle du virus de la leucémie bovine: rôle des facteurs de transcription Sp1/Sp3 et de la méthylation de l'ADN

Wijmeersch, Gaëlle 24 September 2008 (has links)
Étude de la régulation transcriptionnelle du virus de la leucémie bovine :rôle des facteurs de transcription Sp1/Sp3 et de la méthylation de l’ADN / Doctorat en sciences, Spécialisation biologie moléculaire / info:eu-repo/semantics/nonPublished

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