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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.
141

Estudo comparativo de exames clínico-laboratoriais no diagnóstico de carência energética prolongada em garrotes / Comparative study of clinical laboratory assays for the diagnosis of prolonged energetic deficit in steers

Maria Claudia Araripe Sucupira 14 February 2003 (has links)
Para comparar indicadores no diagnostico laboratorial da carência energética e avaliar sua influencia no quadro clínico, 12 garrotes foram aleatoriamente distribuídos em três grupos iguais e receberam , por 140 dias, as seguintes dietas: (G1) adequada, para ganho de peso de 900g/dia (13% de PB e 17,7 Mcal/d de ED); (G2) 80% dos requerimentos de mantença (7% de PB e 5,8 Mcal/d de ED); e (G3) 60% desses requerimentos (5% de PB e 4,7 Mcal/d de ED). Dois animais do G3 sucumbiram ao término do experimento. A carência provocou menor consumo de alimentos, diminui9ao do escore de condição corporal, sem alterar o peso vivo. Embora o volume ruminal tenha sido semelhante entre todos os grupos, as taxa de passagem e de renovação de líquidos foram menores nos grupos carentes. O déficit energético reduziu a produção ruminal de ácidos graxos voláteis totais e de suas frações, o tempo de redução de azul de metileno no suco ruminal foi maior, enquanto que os índices de excreção urinaria de alantoína e de ácido úrico foram menores nos grupos carentes. Os melhores indicadores do status energético foram a glicemia e os teores de β-hidroxibutirato plasmáticos, que reduziram durante a carência: os AGLs não foram eficientes devido a alta variabilidade dos resultados. Não foram detectados corpos cetônicos na urina. O hematócrito e os teores séricos de ureia, albumina, globulinas e creatinina não se mostraram úteis no diagnóstico, porem o índice de excreção urinaria de ureia se reduziu, indicando maior conservação de nitrogênio pelo organismo carente. O déficit energético provocou diminui980 nos batimentos cardíacos, atingindo em quadros avançados 30 bat/min; na frequência respiratória; nos movimentos e tonicidade ruminal. Quanto menor foi a glicemia menores foram os batimentos cardíacos (r= 0,55), a frequência respiratória (r = 0,49) e a tonicidade ruminal (r= 0,81). A temperatura retal permaneceu dentro dos valores de normalidade, mas hipotermia foi detectada precedendo a morte. Levando-se em conta a facilidade, praticidade e custo dos exames, sugere-se o diagnóstico de carência requisitando analise de glicose, β-hidroxibutirato plasmáticos, tempo de redução do azul de metileno no suco ruminal e índice de excreção urinária de ácido úrico. / In order to compare laboratory diagnosis indicators of energetic deficit and evaluate their influence in the clinical picture, 12 steers were randomly distributed in 3 groups of 4 animals, which received the following diets for 140 days : (G1) adequate diet for weight gain of 900g/day (CP: 13% and DE: 17,7 Mcal/d); (G2) 80% of the maintenance requirements (CP: 7% and DE: 5,8 Mcal/d); (G3) 60% of the same requirements (CP: 5% and DE: 4,7 Mcal/d). Two animals from G3 died by the end of the experiment. The nutritional deficit led to lower feed intake and a decrease in the body condition score; without changing body weight. Although the rumen volume was similar in all three groups, the rates of liquid passage and ruminal turnover were lower in G2 and G3. The energetic deficit led to a reduced rumen production of total and fractions of volatile fatty acids. The time of blue methylene reduction in the rumen juice was longer, whereas the index of urinary excretion of allantoin and uric acid was lower in G2 and G3. The best indicators of the energetic status were glycemia and the plasma level of β-hydroxybutirate, which were both reduced during the deficit energetic. NEFA levels were not effective, due to the high variability of the results. Ketone bodies were not detected in the urine. Hematocrit and serum levels of urea, albumin, globulin and creatinin were not useful for malnutrition diagnosis, but the index of urinary excretion of urea was decreased, indicating that malnourished bodies were keeping Nitrogen. The energetic deficit caused a gradual decrease in cardiac rates , falling to 30 beats/min in advanced deficit of energy. Reduced respiratory frequency and rumen tonus was also altered in this condition. Low glycemia was related to decreased heart beat frequency (r=0.55), to respiratory frequency (r=0.49) and to rumen tonus (r=0.81). The rectal temperature remained within normal values; however hypothermia was detected preceding death. Taking into account costs and friendly usage of assays, we suggest the analysis of glucose, plasma β-hydroxybutirate, time of reduction of methylene blue in the rumen juice, and index of urinary excretion of uric acid for the diagnosis of energetic deficit.
142

Desenvolvimento do placentônio em búfalos (Bubalus bubalis bubalisLinnaeus, 1758) / Development of the placenton in water buffalo (Bubalus bubalis bubalis Linnaeus, 1758)

Flávia Thomaz Verechia Pereira 06 April 2000 (has links)
A placenta de ruminantes possui uma estrutura macroscópica uniforme, baseada em áreas especializadas de aposição e proliferação das membranas materno-fetais: os placentônios. Mostrando um papel fundamental para o desenvolvimento da prenhez, estasestruturas tem sido muito estudadas em várias espécies domésticas de interesse comercial. Particularmente no búfalo, entretanto, não há dados consistentes quanto à sua capacidade funcional desta estrutura , ou até mesmo, a arquitetura dos vilosem um placentônio individual e sua troca eficaz de metabólitos que caracteriza o processo de placentação. Um estudo macroscópico prévio da placenta do búfalo (Bubalus bubalis bubalis) mostrou que o número de placentônios é de 92 aproximadamentedurante a prenhez, mas a morfologia microscópica e o desenvolvimento de tais estruturas não foram estudadas em todas as fases da prenhez. Neste trabalho, estudou-se os placentônios de búfalos prenhez nos meses 4-5, 7-8, 9-10, os quais forammorfologicamente caracterizados. Os espécimes foram seccionados e fixados por imersão em paraformoldeído à 4% ou em glutaraldeído à 2,5% em tampão fosfato tamponado 0,1M para microscopia de luz e eletrônica, respectivamente. Após 24 horas, osplacentônios foram recortados e processados para inclusão em paraplast, historesina ou em resina Spurr. As secções foram coradas por HE, Azul de Toluidina, Tricrômicos de Gomori e Mallory, Azul de Metileno com Fucsina Básica e submetidos àreação de PAS. Em todos períodos da prenhez encontrou-se placentônios de diferentes tipos e tamanhos, com uma estrutura macroscópica similar à do placentônio bovino, porém mais achatado. Aparentemente, durante o progresso da prenhez, osplacentônios mantiveram a mesma morfologia macroscópica mas com dimensões aumentadas. À microscopia de luz, a interface entre o trofoblasto e o epitélio uterino é extremamente irregular, formando uma árvore fetal vilosa que se conecta com o epitélio materno. O trofoblasto consiste em uma camada simples de células individuais onde células binucleadas estão interpostas com as células trofoblásticas. O eixo da árvore vilosa é formado fundamentalmente por tecido conjuntivofrouxo, considerando que o eixo interno das pregas epiteliais apresentam um tecido conjuntivo rico em fibras colágenas. Quando comparadas às fases precoces de prenhez, as árvores vilosas dos meses 9-10, são mais ramificadas e a aposição dainterface materno-fetal é mais próxima. Ainda, na junção materno-fetal no final da prenhez, encontrou-se regiões de hematomas e eritrofagocitose o que sugere transferência de ferro para o feto. À microscopia eletrônica de transmissão pudemosobservar uma intensa vascularização do vilo fetal, as células binucleadas apresentaram REG (retículo endoplasmático granular) e Complexo de Golgi bem desenvolvidos, indicando comprometimento com síntese protéica e vesículas eram abundantes. Ascélulas epiteliais trofoblásticas mostraram-se unidas por complexos juncionais, principalmente desmossomas, núcleos de contorno esférico e até dois nucléolos bastante evidentes. Superfícies celulares com microvilos também foram observadas. / The ruminant placenta has an uniform gross structure based on specialized areas of feto-maternal membrane apposition and proliferation: the placentons. By exerting a fundamental role for the development of the pregnancy, these structures have been very well studied in several domestic species of commercial interest. Particularly in the buffalo, however, there is no consistent data with relationship the functional capabilities of this structure or even, the villus architeture in the individual placenton and their metabolic exchange efficacy that characterize the placentation process. One previous macroscopy study on the placenta of buffalo (Bubalus bubalis bubalis) has shown that the number of the placentons is 92 aproximately during pregnancy, but the fine morphology and development of such structures were not studied in all phases of pregnancy. So, in this work, the placentons of pregnant buffaloes on months 4-5, 7-8 and 9-10 were morphologically characterized. The specimens were sectioned and fixed by immersion in either a 4 % paraformaldehyde or in 2.5 % glutaraldehyde in 0.1 M phosphate buffer for light and electron microscopy, respectively. After 24 h, the placentons were cut and processed for embedding in paraplast, historesin or Spurr\'s resin. Sections were stained by HE, Toluidine Blue, Gomori\'s and Mallory\'s trichromes, Methilene Blue and Basic Fucsin and submitted to PAS reaction. In all periods of the pregnancy, we found placentons of different shapes and sizes, with a gross structure similar to the bovine placenton, but more flattened. Apparently, during the progress of the pregnancy, the placentons maintained the same gross morphology but with increased dimensions. At light microscopy, the interface between the trophoblast and the uterine epithelium is extremely irregular forming a fetal villous tree that indents the endometrium. The trophoblast consists of a simple layer of individual cells where binucleated cells are interposed into the remaining trophoblast cells. The axis of the villous tree is fundamentally formed by loose connective tissue, whereas the internal axis of the epithelial folds presented a connective tissue rich in collagen fibers. When compared to early phases of the pregnancy, the villus tree on months 9-10 is much more branched and the materno-fetal interface closely appositioned. Still, in the feto-maternal junction in late pregnancy were found regions of hematomes and erythrophagocytosis. Ultrastructurally, we also observed: the intense vascularization of the fetal villous, binucleated cells presenting a much developed GER (granular endoplasmic reticulum) and Golgi complex, indicating intense secretory activity. The trophoblastic cells showed junctions (desmossomes), euchromatic nuclei and 2 evident nucleoli. The trophoblast and the uterine epithelium were close associated by interdigitated microvilli.
143

Consumo, digestibilidade dos nutrientes e comportamento ingestivo de ovinos com dietas à base de feno de juazeiro (Zizyphus joazeiro) / Intake, apparent digestibility and ingestive behavior in sheep morada nova race fed diets conteining juazeiro (Zizyphos joazeioro) hay

Marcus Roberto GÃes Ferreira Costa 04 December 2008 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Avaliaram-se o consumo, a digestibilidade aparente dos nutrientes e o comportamento ingestivo de ovinos da raÃa Morada Nova, recebendo raÃÃes contendo nÃveis crescentes de feno de juazeiro em substituiÃÃo ao feno de capim-tifton 85 (0, 33, 67 e 100%). Utilizaramse dezesseis ovinos machos, nÃo castrados, com peso mÃdio de 26,75kg, alocados em gaiolas metabÃlicas individuais, distribuÃdos em um delineamento em blocos inteiramente casualizado, com quatro tratamentos e quatro repetiÃÃes. Os consumos de matÃria seca, matÃria orgÃnica, proteÃna bruta, extrato etÃreo, fibra em detergente neutro, carboidratos totais, carboidratos fibrosos, carboidratos nÃo fibrosos e nutrientes digestÃveis totais nÃo foram influenciados pela adiÃÃo do feno de juazeiro Ãs dietas, com valores mÃdios de 1.042,78 e 595,59 g/dia de matÃria seca e fibra em detergente neutro, respectivamente. Observou-se uma reduÃÃo linear para os coeficientes de digestibilidade da matÃria seca, matÃria orgÃnica, fibra em detergente neutro e carboidratos fibrosos. Para o coeficiente de digestibilidade da fibra em detergente Ãcido, observou-se uma reduÃÃo quadrÃtica. Os coeficientes de digestibilidade da proteÃna bruta, extrato etÃreo, carboidratos totais e carboidratos fibrosos nÃo apresentaram variaÃÃes significativas. O balanÃo de nitrogÃnio tambÃm nÃo foi influenciado e apresentou-se positivo para todos os tratamentos. A inclusÃo do feno de juazeiro nÃo influenciou o consumo de nutrientes nem o balanÃo de nitrogÃnio, porÃm reduziu o coeficiente de digestibilidade de alguns componentes da dieta. NÃo se verificou influencia da inclusÃo do feno de juazeiro no tempo despendido para alimentaÃÃo e ruminaÃÃo (min/dia), eficiÃncia de alimentaÃÃo e ruminaÃÃo (g de MS/h e g de FDN/h), dos ovinos em relaÃÃo Ãs dietas experimentais. NÃo houve diferenÃas para o nÃmero de refeiÃÃes/dia, bem como para nÃmeros de perÃodos ruminativos. O feno de juazeiro administrado juntamente com feno de gramÃneas convencionais pode ser uma estratÃgia alimentar para Ãpoca seca no semi-Ãrido nordestino / The intake, the apparent digestibility of nutrients and ingestive behavior of sixteen sheep of Morada Nova race with average weight of 26.75 kg, divided into individual metabolic cages, receiving diets containing crescent levels of juazeiro hay (0, 33, 67 and 100%) were evaluated. A casualized block experimental design with four treatment and four replications was used. Dry matter, organic matter, crude protein, ether extract, neutral detergent fiber,acid detergent fiber, total carbohydrates, carbohydrates fiber and non-fiber carbohydrates intakes were not influenced by addiction of juazeiro hay of the experimental diets, with average value in the 1042.78 and 595 g/day the dry mater and neutral detergent fiber, respectively. Observed a reduction linear for dry matter, organic matter, neutral detergent fiber and carbohydrates fiber digestibility. For acid detergent fiber digestibility observed a reduction quadratic. The crude protein, ether extract, total carbohydrates, carbohydrates fiber digestibility did not present significant variation. The nitrogen balance was not influencing, present positive for treatments. The inclusion of juazeiro hay did not influencing the intake of nutrients, but it reduces the digestibility coefficient in some diet components. The inclusion of hay juazeiro did not influence the ingestive behavior of animals (P> 0.05). The juazeiro hay with convection grass hay is a feeding strategy for northwest semi-arid
144

Enteric and feces methane emissions, fermentative ruminal parameters and feeding behavior of cattle fed cottonseed and vitamin E / Emissões de metano entérico e das fezes, parâmetros fermentativos ruminais e comportamento ingestivo de bovinos alimentados com caroço de algodão e vitamina E

Ricardo Galbiatti Sandoval Nogueira 10 March 2017 (has links)
Problems about greenhouse gas emissions attributed to cattle production and improvements in the productivity of these animals has been growing and becoming increasingly important. Cattle releases methane as part of their digestive process, and this represents loss of energy for the animal. The decomposition of feces releases methane and it can be recovered by digester and transformed into different types of energy. Thus, aiming to quantify the potential production of enteric methane and anaerobic fecal decomposition, as well as to evaluate ruminal and behavioral parameters of cattle fed with cottonseed and vitamin E. Six cannulated cows (864±16 kg) were distributed in a replicate 3x3 Latin square. Treatments were: 1) control diet; 2) CS: basal diet plus 30% cottonseed and 3) CSVitE: basal diet plus 30% of cottonseed plus 500 UI of vitamin E. Results were compared through orthogonal contrast and values were considered significant when P0,05. No differences were observed for dry matter intake (DMI), as well as digestibility of DM and neutral detergent fiber (NDF). Animals supplemented with cottonseed spent more time eating and ruminating and less time in idles. Reduction in the concentration and production of acetate, butyrate and the acetate: propionate ratio was observed in animals fed cottonseed compared to the control. Enteric methane mitigation was observed for the cottonseed treatments compared to the control. Changes in the substrates characteristics used to load the digesters were observed. However, no differences were verified for the total biogas production, methane yield and capacity to recover the energy of the feces in the form of methane. Inclusion of 30% cottonseed can be used as a strategy to mitigate enteric methane, without causing losses in the DMI, nutrients digestibility and anaerobic digestion of feces. In addition, it promoted favorable changes in the ingestive behavior, ruminal fermentation products, as well as in the energy partition of the gastrointestinal tract. Vitamin E when is used as antioxidant had not effect on ruminal fermentation, feeding behavior and feces anaerobic digestion, thus the inclusion is not advised due absence of positive results. / A problemática das emissões de gases de efeito estufa atribuída à produção de bovinos e melhorias na produtividade desses animais vem crescendo e se tornando cada vez mais importante. Bovinos emitem metano como parte do seu processo digestivo, e isto representa perda de energia para o animal. A decomposição das fezes gera metano, este pode ser recuperado por biodigestores e transformado em diferentes tipos de energia. Assim, objetivou-se quantificar o potencial de produção do metano entérico e da decomposição anaeróbia das fezes, bem como avaliar parâmetros ruminais e comportamentais de bovinos alimentados com caroço de algodão e vitamina E. Foram utilizadas seis vacas fistuladas não gestantes e não lactantes (876 kg±16). Os tratamentos foram: 1) Controle: dieta basal; 2) CA: dieta basal mais 30% de caroço de algodão; 3) CAVitE: dieta basal mais 30% de caroço de algodão mais 500 UI vitamina E. O delineamento experimental utilizado foi o quadrado latino. Os resultados foram comparados por contrastes ortogonais e foram considerados significantes valores de P0,05. Não foram verificadas diferenças para o consumo de matéria seca (MS), bem como digestibilidade da MS e da fibra em detergente neutro (FDN). Os animais suplementados com caroço de algodão passaram maior tempo comendo e ruminando e menor tempo em ócio. Houve redução na concentração e produção de acetato, butirato e da relação acetato:propionato dos animais que receberam caroço de algodão comparado ao controle. A inclusão do caroço de algodão provocou mitigação das emissões de metano entérico. Houve alteração nas características dos substratos utilizados para abastecer os biodigestores. No entanto, não foram verificadas diferenças para a produção total de biogás, rendimento de metano e capacidade dos biodigestores em recuperar a energia das fezes na forma de metano. A inclusão de 30% caroço de algodão pode ser utilizada como estratégia para mitigar metano entérico, sem causar perdas no consumo, digestibilidade dos alimentos e na biodigestão anaeróbia das fezes. Além disso, sua inclusão promoveu alterações favoráveis no comportamento ingestivo, nos produtos da fermentação ruminal, bem como na partição de energia do trato gastrointestinal. A vitamina E quando utilizada como antioxidante não possui efeitos sobre a fermentação ruminal, comportamento ingestivo e biodigestão anaeróbia das fezes, assim sua inclusão não é indicada devido a ausência de resultados favoráveis a sua utilização.
145

Energy requirements, energetic partition and methane emission from growing Holstein, Gyr and F1 Holstein-Gyr dairy heifers / Exigências de energia, partição energética e emissão de metano por novilhas leiteiras Holandês, Gir e F1 Holandês-Gir em crescimento

Tainá Silvestre Moreira 29 August 2016 (has links)
In Brazil, country with the fifth largest world production of milk, diets formulations are also carried out on the basis of nutritional requirements established in other countries, especially those from predominantly temperate climate. Research validation nutritional systems have evidenced application incompatibility of systems generated in temperate conditions at tropical conditions. Thus, the aim of this study was to determinate energy requirements, energetic partition and methane (CH4) enteric emission from growing Holstein, Gyr and F1 Holstein-Gyr dairy heifers in tropical conditions. The trial was conducted at The Multi-use Livestock Complex of Bioefficiency and Sustainability at Embrapa Dairy Cattle, Coronel Pacheco - MG, Brazil. Were evaluated 36 heifers, 12 Holstein, 12 Gyr and 12 Holstein-Gyr in 3 distinct experiments. In the first one, the 36 heifers were distributed in 12 latin squares, in a 3x3 factorial arrangement which was 3 nutritional plans and 3 genotypes. The nutritional plans were (1) 1.0x maintenance; (2) 1.5x maintenance and (3) 2.0x maintenance and the heifers were fed a diet consisting of 85.0% of corn silage and 15.0% of concentrate on a dry matter (DM) basis. Enteric CH4 emission was evaluated by SF6 tracer technique. Dry matter intake (DMI) and nutrients presented interaction among genotype and nutritional plan. Gyr heifers demonstrated higher crude protein (CP) digestibility (76.55%), F1 Holstein-Gyr intermediary value (75.14%) and Holstein animals presented the lowest value (74.59%). Daily CH4 production (g/d) was influenced by nutritional plan and differed as well between genotypes whereas Gyr heifers compared to the others had lesser CH4 emissions. Heifers fed at lower nutritional plan presented highest (85.5%) CH4 emissions by average daily gain (g/ kg of ADG) when compared to heifers fed at the higher nutritional plan. We found annual emissions of 45.84 kg of CH4. The second experiment has as objective measure the heat production (HP) and the enteric CH4 emission from dairy heifers using face mask (FM) method. The same animals, treatments and diets that were used in the first study were used in this second and third one. The HP expressed in Mcal by metabolic body weight (Mcal/BW0.75) was affect by genotype and Gyr heifers presented lower HP (163.2) when compared to Holstein (201.0) while F1 Holstein-Gyr heifers did not differ (181.3). Observed interaction among genotype and nutritional plan to CH4 emission in (g/d) and grams per kilo of metabolic body weight (g/kg of BW0.75). When expressed in dry matter ingested was not found genotype or nutritional plans effects to CH4 production. In the third study, our objective was to determine energy requirements, energetic partition and enteric CH4 emission using the \"gold standard\" methodology as calorimetric respirometry. Each heifers spent one 24 hours period in an open-circuit respirometric chamber (RC) to measurements. The CH4 emission was influenced by genotype and nutritional plan. Holstein and F1 Holstein-Gyr heifers demonstrated 73.4% superior emissions when compared to Gyr heifers. The net energy requirements for maintenance (NEm/kcal BW0.75) was 103.9 for Holstein heifers, 79.86 for Gyr heifers and 103.8 for F1 Holstein-Gyr heifers. The metabolizable energy requirements for maintenance (MEm/kcal BW0.75) was 132.6 for Holstein heifers, 116.0 for Gyr heifers and 138.2 for F1 Holstein-Gyr heifers. Were not found differences among Holstein and F1 heifers on NEm and MEm, so was formulated a combined equation for both, where the net and metabolizable energy requirements for maintenance were 105.2 and 135.0 kcal/BW0.75, respectively. We concluded that our results about nutritional requirements had similarity with available literature from respirometric chambers. These generated data from dairy cattle will be used for a future data base vising the establishment of feed patterns for representative dairy cattle genotypes in national herd composition. Also, the enteric methane emission data obtained in this study will be used in the greenhouse gases national inventory. / No Brasil, país com a quinta maior produção mundial de leite, as formulações de dietas ainda são realizadas com base nas exigências nutricionais estabelecidas em países de clima predominantemente temperado. Pesquisas de validação de sistemas nutricionais têm evidenciado incompatibilidade de aplicação dos sistemas gerados em condições temperadas às condições tropicais. Assim, objetivou-se com o presente trabalho determinar as exigências de energia, a partição da energia consumida e emissão de metano (CH4) entérico de novilhas leiteiras em crescimento das raças Holandês, Gir e F1 Holandês-Gir, em condições tropicais. O experimento foi realizado no Complexo Experimental Multiusuário da Embrapa Gado de Leite, localizado no Campo Experimental José Henrique Bruschi, em Coronel Pacheco - MG. Foram avaliadas 36 novilhas leiteiras, sendo 12 da raça Holandês, 12 da raça Gir e 12 F1 Holandês-Gir em 3 experimentos distintos. No primeiro experimento, as 36 novilhas foram distribuídas em 12 quadrados latinos, em arranjo fatorial 3x3, ou seja, 3 planos nutricionais e 3 grupos genéticos. Os planos nutricionais foram (1) 1.0x mantença; (2) 1.5x mantença e (3) 2.0x mantença e as novilhas foram alimentadas com uma dieta constituída de 85.0% de silagem de milho e 15.0% de concentrado com base na matéria seca (MS). A metodologia empregada para mensuração de CH4 foi a técnica do gás traçador SF6. O consumo de matéria seca (CMS) e nutrientes apresentou interação entre genótipo e plano nutricional. Novilhas da raça Gir apresentam maior digestibilidade da proteína bruta (76,55%), as F1 Holandês-Gir valor intermediário (75,14%) enquanto que os animais da raça Holandês apresentaram o menor valor (74,59%). A produção diária de metano em grama dia (g/d) foi influenciada pelo plano nutricional e também diferiu entre grupo genético, sendo que novilhas da raça Gir quando comparadas às demais tiveram menor emissão de CH4 entérico. Novilhas alimentadas sob o menor plano nutricional apresentaram maior emissão de CH4 (85,5%) por ganho de peso diário (g/kg de GPD) quando comparada as novilhas sob o maior plano nutricional. A produção média de CH4 anual encontrada no presente estudo foi de 45,84 kg. O segundo experimento teve como objetivo mensurar a produção de calor (PC) e a emissão de CH4 entérico por novilhas leiteiras através do método da máscara facial. Os mesmos animais, tratamentos e dietas que foram utilizadas no primeiro estudo foram utilizados neste estudo e no estudo que será descrito posteriormente a esse. A PC expressa em Mcal por peso vivo metabólico (Mcal/PVM) foi afetada por genótipo e novilhas da raça Gir apresentaram menor PC (163,2) quando comparada as novilhas Holandês (201,0) enquanto que as novilhas F1 Holandês-Gir não diferiu das demais (181,3). Observou-se interação entre genótipo e plano nutricional para emissão de CH4 em grama dia e em grama por quilo de peso vivo metabólico. Quando expresso em relação à matéria seca ingerida, não foram encontrados efeitos de genótipo ou plano nutricional para emissão de CH4. O terceiro estudo objetivou determinar as exigências de energia, a partição energética e a emissão metano entérico pela metodologia padrão de respirometria calorimétrica. Cada novilha permaneceu por um período de 24 horas no interior da câmara para as mensurações. A emissão de CH4 (g/d) foi influenciada por genótipo e plano nutricional. Novilhas Holandês e F1 Holandês-Gir demonstram emissões superiores em 73,4% quando comparadas as novilhas da raça Gir. A exigência de energia líquida para mantença (ELm/kcal BW0,75) foi 103,9 para novilhas Holandês, 79,86 para novilhas Gir e 103,8 para novilhas F1 Holandês-Gir. A exigência de energia metabolizável para mantença (EMm/kcal BW0,75) foi 132, 6 para novilhas Holandês, 116,0 para novilhas Gir e 138,2 para novilhas F1 Holandês-Gir. Não foram encontradas diferenças entre novilhas Holandês e F1 Holandês-Gir para exigências de ELm e EMm, então foi formulada uma equação combinada para ambas, onde ELm e EMm foram 105,2 e 135,0 kcal/BW0,75, respectivamente. Concluiu-se que os atuais resultados de exigências em energia tiveram similaridade com a literatura disponível e serão utilizados para inclusão no banco de dados de gado de leite, a ser formado com trabalhos já existentes e outros que ainda serão desenvolvidos, visando ao futuro estabelecimento das normas e padrões nacionais de alimentação para bovinos leiteiros dos grupos genéticos mais representativos do rebanho nacional. Os dados de emissão de metano entérico obtidos poderão ser utilizados na elaboração do inventário nacional de emissão de gases de efeito estufa pelas atividades pecuárias.
146

The impact of brucellosis in Albania : a systems approach

Bruce, Mieghan January 2016 (has links)
No description available.
147

Livelihoods of Fulani pastoralists and burden of bacterial zoonoses in the Kachia grazing reserve, Nigeria

Ducrotoy, Marie Julie January 2015 (has links)
The work presented focuses on bacterial zoonoses in northern Nigeria, and more specifically on brucellosis in the Kachia grazing reserve (KGR) - rangeland set-aside by the government to sedentarise Fulani pastoralists. The objectives of the study were to 1) undertake demographic and socioeconomic profiling of the KGR community; 2) review the evidence for brucellosis burden in Nigeria; 3) assess the suitability and performance of brucellosis diagnostic tests selected for use; 4) compare burden of brucellosis across different species (animal and human) and determine Brucella species present in KGR; 5) explore social or environmental factors which may promote or prevent brucellosis transmission; 6) make recommendations for brucellosis control in the KGR and Nigeria; 7) explore community perception of disease and determine household expenditure on animal health; 8) critically evaluate the system’s, integrated, disease cluster, ‘One Health’ approach applied in this study. Three surveys comprising animal (cattle, sheep and goat) and human sampling, administration of questionnaires, focus group discussions and key informant interviews were undertaken in March, June and October 2011. A population census was undertaken in June 2011. Comparison of 2010 government census data with June 2011 census data showed that a mass immigration event occurred in April-May 2011 as a result of post-election violence, with cattle and human populations increasing by 75%. Questionnaire and census data demonstrated the diversity and heterogeneity of the Fulani community in terms of wealth status (roughly corresponding to livestock assets), household size and composition and livelihood diversification strategies. While Fulani in grazing reserves were assumed to be sedentary, KGR households were found to practice wide-range dry and wet season transhumance. Cattle productivity parameters and herd dynamics were similar to those reported by other authors for the extensive pastoralist systems in the sub-humid zone. Herd increase over a one-year period was found to be low or negative for most households in this low input, low output system. Brucellosis epidemiology in the KGR involves B. abortus biovar 3a with low individual and moderate cattle herd prevalence and occasional spill-over into small ruminants. No human brucellosis was detected despite over 80% of the KGR population consuming raw milk and engaging in risky behaviours, raising questions about the potential lower virulence of the local biovar. Low infection rates in livestock, disease-reducing intuitive behaviours or immunity may also be at play. The RBT was found to perform well under field conditions, despite poor concordance when applied in different laboratories and under different conditions. Prospects for control/elimination of brucellosis in the KGR are poor, but low animal burden and absence of human disease render vaccination uneconomic. A review of the literature in Nigeria suggests that brucellosis burden is higher in intensive livestock production systems, which should be targeted first. A laissez-faire approach to brucellosis control in the nomadic pastoralist domain may appeal to policy-makers, as interventions in migratory populations are difficult. Brucellosis is perceived by the KGR community as the number three-priority disease, after trypanosomiasis and Fasciola gigantica/clostridial infection and this was reflected in household expenditure on chemotherapeutics and prophylaxis. Finally, the value of the One Health approach is the ability to see the whole picture, including disease impacts in the animal reservoir as well as the human population, without which erroneous epidemiological and economic conclusions may be drawn; for example, presence of brucellosis in the animal reservoir does not necessarily indicate presence of human disease. This work shows that moving from disciplinary silos to a more holistic or system’s approach spanning epidemiology, evaluation of diagnostic and control tools as well as socio-economic, cultural and institutional aspects can lead to more appropriate recommendations for disease control.
148

The effect of blood urea nitrogen on reproductive performance of beef heifers on different levels of nitrogen supplementation

Tshuma, Takula January 2013 (has links)
Ruminants have a unique ability to acquire protein from non-protein nitrogen (NPN) sources, and to recycle nitrogen back into the rumen, instead of excreting all of it via the urine, faeces and milk. However, a high concentration of blood urea nitrogen (BUN) has a negative influence on conception. Additionally, a high dietary nitrogen intake poses a challenge to the environment in the form of ammonia emissions, eutrophication and bad odours. This calls for strategies to reduce the environmental impact of livestock production. Variation exists in the ability of cattle to recirculate nitrogen between as well as within cattle breeds. The purpose of this study was to investigate the effects of BUN concentration on reproductive performance in beef heifers under different management systems in South Africa. Serum samples from 369 Bonsmara heifers were taken in November and December 2010 to determine the BUN concentrations prior to the onset of the breeding season. Heifers were from five herds with different levels of protein supplementation during the weeks before the commencement of the breeding season. Body mass, age, body condition score (BCS) and reproductive tract score (RTS) were recorded at the same time as BUN concentration. Trans-rectal ultrasound and/or-palpation was performed four to eight weeks after the three-month breeding season to detect and estimate the stage of pregnancy. Days to pregnancy (DTP) was defined as the number of days from the start of the breeding season until a heifer was successfully mated. Logistic regression and Cox proportional hazards survival analysis were performed to estimate the effect of BUN concentration on subsequent pregnancy and DTP respectively, while stratifying by herd and adjusting for potential confounders. The correlations between BUN concentration, BCS and RTS were estimated using Spearman’s rho. Pearson correlations were used for the normally distributed variables of age and body mass. BUN concentration was not a significant predictor of pregnancy status but was a significant (P = 0.007) and independent predictor of DTP in heavily and some moderately supplemented herds. As BUN concentration increased, DTP also increased [hazard ratio (HR) = 0.827; 95% CI: 0.721 – 0.949; P = 0.007], while the chance of becoming pregnant decreased, although this was not statistically significant [odds ratio (OR) = 0.882; 95% CI: 0.772 – 1.007; P = 0.063]. Bonsmara heifers with higher BUN concentration, which suggests a better ability to recirculate nitrogen, might be at a disadvantage when the production system includes high levels of RDP supplementation because of this negative impact on reproductive performance. It is proposed that production systems be adapted to avoid selection against animals with an improved ability to recirculate nitrogen. / Dissertation (MMedVet)--University of Pretoria, 2013. / gm2014 / Production Animal Studies / Unrestricted
149

Molecular characterisation of peste des petits ruminants viruses in sheep and goats from Nigeria

Mantip, Samuel Elias Lashat January 2013 (has links)
Peste des petits ruminants virus (PPRV) belongs to the family Paramyxoviridae and genus morbillivirus. It is a highly contagious, fatal and economically important viral disease of small ruminants that is still endemic and militate against the production of sheep and goats in Nigeria. It is a notifiable disease according to the World Organization for Animal Health (Office International des Epizooties). In this study, a molecular analysis of PPRV from sheep and goats from recent outbreaks across the different regions of Nigeria was carried out. The aim was to describe the viral strains and the movement of the virus within the country compared to other endemic areas of the world. This was carried out through tissue and swab samples collected from sheep and goats in various agro-ecological zones of Nigeria.The evolution and relationship of earlier PPRV strains/isolates and those circulating and causing recent outbreaks was determined by sequencing of the nucleoprotein (N)-gene. Twenty tissue and swab samples from apparently healthy and sick sheep and goats were collected randomly from each of three states of each of the six agro-ecological zones visited. A total of 360 samples were collected. A total of 35 samples of 360 (9.7 %) tested positive by RT-PCR, of which 25 were from oculo-nasal swabs and 10 were from tissue samples (Table 4.2). Phylogenetic analysis was carried out using the N-gene sequences of the PPRV amplicons. Alignment of the sequences and related sequences from GenBank and neighbor-joining phylogenetic analysis using PAUP identified four different lineages, i.e. lineages I, II, III and IV. Interestingly, the Nigerian strains described in this study grouped in two separate major lineages i.e. lineages II and IV. Strains from Sokoto, Oyo, Plateau and Ondo states grouped according to the historical distribution of PPRV together with the Nigerian 75/1 strain of lineage II, while other strains from Sokoto, Oyo, Plateau, Akwa-Ibom, Adamawa, Kaduna, Lagos, Bauchi, Niger and Kano states grouped together with the East-African and Asian strains of lineage IV. This finding suggests that both lineages II and IV strains of PPRVs are circulating presently in Nigeria, contrary to an earlier publication which indicated that only strains of lineage II were circulating in the country (Shamaki, 2002). / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Veterinary Tropical Diseases / unrestricted
150

Impacto de diferentes protocolos de corticoterapia antenatal na produção de hidroperóxidos e na capacidade antioxidante em cabritos e cabras pós-parto /

Silva, Eva Liliane dos Santos. January 2018 (has links)
Orientador: Francisco Leydson Formiga Feitosa / Banca: Flávia de Almeida Lucas / Banca: Vanessa Veronese Ortunho / Resumo: Este trabalho teve como objetivo mensurar a produção de hidroperóxidos e a capacidade antioxidante do plasma de cabras e seus cabritos, por meio do teste d-ROMs (Reactive Oxygen Metabolites) e BAP (Biological Antioxidant Potential), após as cabras serem submetidas a diferentes protocolos de corticoterapia antenatal, os animais foram aleatoriamente alocados em quatro grupos experimentais: grupo I - constituído por quatro cabras e sete cabritos, com uma única dosagem de 20 mg de dexametasona, por via IM/SID, dois dias antes da cirurgia eletiva (139 dias); grupo II - composto por quatro cabras e seis cabritos utilizando a dosagem de 2 mg de dexametasona, dos 133 aos 136 dias; 4 mg dos 137 aos 138; e 20 mg aos 139 dias de prenhes, por via IM/SID; grupo III - constituído por quatro cabras e sete cabritos, com dosagem de 16 mg de dexametasona aos 139, com doses repetidas a cada 12 horas até a cirurgia eletiva, por via IM/BID, e grupo IV - composto por quatro cabras e seis cabritos utilizando a dose de 4, 8, 16 e 20 mg de dexametasona, por via IM/SID, aos 137, 138, 139, 140 dias de gestação, respectivamente. Para analisar d-ROMs e BAP foram feitas coletas de sangue nas cabras por punção da veia jugular aos 15 minutos (M15) após o parto, e nos cabritos foram realizadas as coletas de sangue por punção da veia jugular nos respectivos momentos com referência ao nascimento de cada neonato: 15 minutos (M15), 24 horas (M24) e 48 horas (M48). / Abstract: The objective of this work was to measure the production of hydroperoxides and the antioxidant capacity of goats and their goats by means of the d-ROMs test (Reactive Oxygen Metabolites) and BAP (Biological Antioxidant Potential), after the goats were submitted to different protocols of antenatal corticosteroid therapy, the animals were randomly assigned to four experimental groups: group I - consisting of four goats and seven goats, with a single dose of 20 mg of dexamethasone, IM / SID, two days before elective surgery (139 days); group II - composed of four goats and six goats using the dosage of 2 mg dexamethasone, from 133 to 136 days; 4 mg of 137 to 138; and 20 mg at 139 days of pregnancy, by IM/SID; group III - consisting of four goats and seven goats, with a dose of 16 mg of dexamethasone at 139, with repeated doses every 12 hours until elective surgery, by IM/BID, e group IV - composed of four goats and six goats using the dose of 4, 8, 16 and 20 mg dexamethasone, by IM / SID route, to the 137, 138, 139, 140 days of gestation, respectively. Blood samples were taken from the goats by puncture of the jugular vein at 15 minutes (M15) after calving and the kidneys were collected by puncturing the jugular vein at the respective moments with reference to the birth of each neonate: 15 minutes (M15), 24 hours (M24) and 48 hours (M48). / Mestre

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