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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.
11

Broiler producers´ perspectives on bacterial resilience; evaluating a potential of hops

Gustafsson, Erik January 2019 (has links)
An interview study was undertaken to explore Swedish broiler producers´ views for the potential of hops (H. lupulus L.) to reduce reliance on ionophorous coccidiostats in broiler production. The design was a mixed methodology between grounded theory and case study with a semi structured interview method. Nine producers, four using ionophorous coccidiostats and five without reliance in production accepted interview. During interviews participants were presented to research conducted with hops in production and consequences from ionophores in production. All participants thought the risk from pathogen pressure was too great to cut reliance in intensive production owed to the lower efficacy of hops. Therefore owed to how actors in the Swedish food system behave only small producers with enough economical freedom for reduced stocking densities were regarded to be able to uphold animal health with hops. Six parameters within food systems were regarded as leverage points for a potential of hops in production on a larger societal scale if encouraging a more extensive nationwide production system. Those were: purchase will, small local production, increased responsibility within trade, law, elevated consumers and research. Law was seen as a necessity to enforce all other denominators since economical in food systems tend to override social and ecological dimensions. Consequences from power struggle in food systems disfavoring producers has although resulted in a great distrust towards other system actors such as consumers, legal institutions or wholesalers. That has created a reluctance to interact with other system actors even for common goals. A stronger position to other actors in food systems was regarded as increasing a meaningful outcome from interaction. Four parameters emerged as impacting power relations in a system the most: Purchase will, contracts, own designed production and law. Favorable purchase will and law would contribute the most for increasing adaptivity for alternatives in production by impacting on power relations. No producers had observed indicators of bacterial resistance from ionophorous coccidiostat usage. Lack of research for many years in the field was troublesome for how to develop the enterprise according to participants. Especially in relation to Norway that has abolished the static use of ionophorous coccidiostats in production. About half of the participants although regarded a shift in research towards consequences from intensive production as equally important as focusing on alternative antimicrobials.
12

O efeito do óleo-resina de copaíba sobre o desempenho e imunidade de frangos desafiados com escherichia coli patogênica / The effect of oil-resin from copaíba on performance and immunity of chicken challenged with pathogenic escherichia coli

Guidotti, Micaela 04 June 2013 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-29T14:43:20Z No. of bitstreams: 2 Guidotti, Micaela-2013-dissertação.pdf: 5573405 bytes, checksum: 6c218b2a095f16e608d6d6a1179ebee5 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-29T15:13:32Z (GMT) No. of bitstreams: 2 Guidotti, Micaela-2013-dissertação.pdf: 5573405 bytes, checksum: 6c218b2a095f16e608d6d6a1179ebee5 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-29T15:13:32Z (GMT). No. of bitstreams: 2 Guidotti, Micaela-2013-dissertação.pdf: 5573405 bytes, checksum: 6c218b2a095f16e608d6d6a1179ebee5 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-06-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aim of this work was to evaluate the effect of oil-resin from the plant Copaifera sp. as phytogenic additive on broiler performance and as immunomodulatory agent. Five hundred broiler chicks were used (Cobb500 males), distributed in a randomized design experiment in factorial 5 x 2, composed of 10 treatments and five replications with 10 birds per pen. The treatments were divided in animals challenged and not challenged for all treatments: control group with and without challenge, oil-resin from copaiba 0.2%, group oilresin from copaiba 0.4%, group of oil-resin from copaiba 0.6 and group with growth promoter colistin. The challenge with pathogenic E. coli (4.5 x 109 UFCmL ) was realized at the age of four and 22 days old. The final weight, weight gain, feed intake and feed conversion were measured at weekly intervals until the age of 28 days. A in house indirect ELISA was standardized and immunoglobulin class IgA was evaluated. The cellular immunity was measured through skyn reaction test to phytohemagglutinin and analyzing the relative weight of the lymphoid organs. Performance data were analyzed through ANOVA and Turkey test with 5% of probability. For statistical evaluation of immunological data it was used multiple test non-parametric test, Kruskall-Wallis followed by T teste. The results showed that the inclusion of different levels of oil-resin from copaiba in broiler diet had similar performance when compared to the inclusion of antibiotic growth promoter. However it was observed an additive effect on antibody levels at the end of the trial period when oil-resin 0.2% was used. / Objetivou-se com este trabalho avaliar o efeito do óleo-resina da planta Copaifera sp. como aditivo fitogênico sobre os parâmetros de desempenho e como agente imunomodulador. Foram utilizados 500 pintos de corte machos Cobb500, distribuídos em delineamento inteiramente casualizado, em esquema fatorial 5x2, composto por 10 tratamentos e cinco repetições com 10 aves por unidade experimental. Os tratamentos foram divididos em animais desafiados e não desafiados para todos os tratamentos: grupo controle com e sem desafio, grupo com nível de inclusão de óleo-resina de 0.2% com e sem desafio, grupo com nível de inclusão de óleo-resina de copaíba 0.4% com e sem desafio, grupo com nível de inclusão de óleo-resina de copaíba 0.6% com e sem desafio, grupo com promotor de crescimento colistina com e sem desafio. O desafio microbiano foi fornecido as aves aos quatro dias de idade e aos 22 dias de idade contendo 4,5 x 109 UFC/mL. O peso final, ganho de peso, consumo de ração e conversão alimentar foram mensurados semanalmente até os 28 dias de idade das aves. Foi realizado a padronização de um teste de ELISA indireto para pesquisa de imunoglobulinas da classe IgA e avaliação da imunidade celular por meio de teste de reação a fitohemaglutinina e ao peso relativo dos órgãos linfóides. Os dados de desempenho foram analisados por meio do teste de ANOVA e Turkey a 5% de probabilidade. Para avaliação estatística para os dados imunológicos foi utilizado teste múltiplos nãoparamétrico de Kruskall-Wallis seguidos de teste T para comparação entre os diferentes grupos. Os resultados demonstraram que a inclusão de diferentes níveis de óleo-resina de copaíba na dieta de frangos de corte apresentaram efeito semelhante ao promotor de crescimento antibiótico e apresentou efeito aditivo nos níveis de anticorpos ao final do período experimental no nível de 0.2% de óleoresina.
13

AVICULTURA DE CORTE BRASILEIRA: DESEMPENHO RECENTE E COMPETITIVIDADE INTERNACIONAL / BRAZILIAN BROILER PRODUCTION: CURRENT PERFORMANCE AND INTERNATIONAL COMPETITIVENESS

Bertoglio, Oscar 18 August 2006 (has links)
Many productive sectors, like the Brazilian broiler one, have increased along the last decades. Taking into account meaningful changes related to the organization of agroindustrial systems since the 1960s, besides the increasing industrial investments into the process, Such sectors have improved due to technological development which helped them to succeed in international markets. Until the mid- 1980s, the Brazilian broiler sector had almost its whole production internally consumed. In this sense, investors started to consider broiler production as an alternative business worthy of huge investments. Such activity was spread and developed over many countries, especially in The United States, France, and more recently in China, which prompted the level of competitiveness among worldwide producers. In this way, there is a need of deep evaluation concerning the Brazilian broiler production chances of competitiveness into the international market. Studies have shown that the growth of Brazilian broiler exports is linked to comparative advantages, highly influenced by public politics or artificial international competitive practices. Bearing this in mind, this research aims at evaluating Brazilian broiler production performance, from such analysis it is possible to demonstrate rates showing comparative/competitive advantages into the Brazilian sector. Besides that, this study also considers the kind of incomes such activity has received or if it has been developed according to the theory of comparative advantages In order to meet these objectives, it is necessary, firstly, to evaluate the performance of the main elements into the broiler production process, such as production, consumption, exports, imports, in comparison to worldwide data. Secondly, following the Policy Analysis Matrix methodology, rates will be shown in order to point level of broiler production economic viability, protective/ deprotective levels as its establishment all over the world. The detailed analysis points out i) the Brazilian broiler activity has shown increasing development according to the various rates; ii) In Brazil, such activity has developed above the international average, which reflects into its participation into the international market; iii) Brazil is the third biggest producer of broiler in the world and its main exporter, responsible for 40 % of the whole exports in 2005; iv) the growth of Brazilian participation is linked to comparative advantages; v) the current international and national politics have caused a deprotective consequence into the Brazilian sector which privilege other countries such as the United States. Even though, the Brazilian productive can still be internationally competitive; vi) with the reduction into protective measures in relation to other markets, Brazil can prevail with its broiler production targeted at international market / A partir das relevantes transformações na organização dos sistemas agroindustriais, ocorridas a partir da década de 60, juntamente com a crescente participação do capital industrial nesse processo, muitos setores produtivos, entre eles o setor avícola de corte brasileiro, lograram expressivas taxas de crescimentos ao longo das últimas décadas. Isso só foi possível porque tais setores experimentaram crescentes ganhos tecnológicos reunindo as pré-condições para, também, conquistar mercados externos. Especificamente ao setor avícola de corte brasileiro, tem-se que até meados da década de 80, quase a totalidade da produção era absorvida internamente. Diante disso, os investidores perceberam que a atividade avícola de corte representava uma importante alternativa de remuneração de capitais e com isso, a partir de vultosos investimentos, a atividade se desenvolveu e se consolidou em diversos países do mundo, com destaque para os Estados Unidos e França, e mais recentemente a China, elevando o grau de competição entre os diversos produtores mundiais. Diante disso, surge à necessidade de avaliar, com mais profundidades, quais as reais possibilidades do setor brasileiro competir em âmbito mundial. É recorrente na literatura especializada uma questão: o crescimento da participação das exportações da avicultura brasileira no total exportado pelo resto do mundo se deve às vantagens comparativas reais? ou a atividade se desenvolve na alavanca de políticas públicas que protejam os produtores brasileiros? ou então, de práticas que garantam competitividade internacional de forma artificial? Nesse sentido, o objetivo deste estudo é avaliar o desempenho da atividade avícola de corte no Brasil, e a partir daí construir indicadores que demonstrem ou refutem as vantagens comparativas/competitivas do setor brasileiro. É de interesse desse estudo, também, avaliar em que grau o setor da avicultura de corte brasileira recebeu incentivos ou desincentivos para a prática da atividade, ou se ela se desenvolve seguindo os preceitos da teoria das vantagens xiv comparativas. No desafio de atingir os objetivos propostos, é avaliado, inicialmente, o desempenho dos principais elementos dentro da atividade, como produção, consumo, exportação, importação, sempre confrontando com o desempenho dessa atividade em nível mundial. Numa segunda etapa, utilizando a metodologia denominada Matriz de Análise Política (MAP), são construídos indicadores que avaliam os graus de lucratividade/rentabilidade da atividade, o grau de proteção/desproteção que o setor possui, assim como os reais níveis em que a atividade é protegida/desprotegida em âmbito mundial. As principais constatações feitas, após uma análise detalhada do que foi proposto foram: i) a atividade da avicultura de corte brasileira apresentou crescimentos expressivos nos diversos indicadores avaliados; ii) no Brasil a atividade cresceu bem acima da média mundial, conseguindo aumentar sua participação no cenário internacional; iii) o Brasil figura como terceiro maior produtor mundial e principal exportador, detendo 40% das exportações totais no ano de 2005; iv) o aumento de participação no cenário mundial se deu a partir de vantagens comparativas reais; v) as políticas em vigor, em nível nacional e internacional geram desproteção ao setor brasileiro e conseqüentemente proteção a outros países produtores, especificamente, Estados Unidos, mesmo assim, esse ramo produtivo brasileiro consegue ser competitivo em âmbito internacional; vi) a partir da redução das proteções em outros mercados, o Brasil tem condições de consolidar-se, ainda mais, como grande produtor e exportador de carne de frango, em nível mundial

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