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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

Fungos, micotoxinas e fitoalexina em variedades de amendoim do plantio ao armazenamento. / Fungi, mycotoxins phytoalexin in peanut varieties, during plant growth from the field to storage.

Zorzete, Patricia 07 December 2010 (has links)
O trabalho avaliou micobiota, contaminação por aflatoxinas (AFB), ácido ciclopiazônico (ACP) e fitoalexina (trans-resveratrol) nas variedades de amendoim Runner IAC 886 e IAC-Caiapó, no campo e armazenamento. Nas amostras de campo, na IAC 886 predominou Fusarium spp. nos grãos e cascas, contaminação por AFB em 30% dos grãos, ACP em 70% e trans-resveratrol em 5%. Na IAC-Caiapó prevaleceu Fusarium spp., em todas as amostras, AFB em 25% dos grãos, ACP em 55% e trans-resveratrol em 15%. Nas folhas, trans-reveratrol estava presente em 70%, nas variedades. No armazenamento, observou-se maior freqüência de A. flavus, A. parasiticus. Na IAC 886 AFB foi detectada em 20% nos grãos e 23% nas cascas e ACP em 80% dos grãos. Na IAC-Caiapó, AFB foi encontrada em 13% tanto nas amostras de grãos, como nas cascas e ACP em 70% dos grãos. Os resultados do potencial toxigênico de A. flavus revelaram 81% produtores de aflatoxinas, 95% de ACP e 75% de ambas. Todos A. flavus produtores de esclerócios pertenciam ao grupo L. / This study had assessed mycobiota, contamination by aflatoxins (AFB), cyclopiazonic acid (CPA) and phytoalexin (trans-resveratrol) in the peanuts varieties Runner IAC 886 and IAC-Caiapó, in the field and storage. In the Field samples, in IAC 886 it was predominated Fusarium spp. in grains and shells, contamination by AFB in 30% of the grains, CPA in 70% and trans-resveratrol in 5%. In IAC-Caiapó, it was prevailed Fusarium spp. in all samples, AFB in 25% of the grains, CPA in 55% and trans-resveratrol in 15%. In the leaves, trans-resveratrol was present in 70% in the varieties. In the storage, it was observed a higher frequency of A. flavus, A. parasiticus. In IAC 886, it was detected AFB in 20% of the grains and 23% in the shells, and CPA in 80% of the grains. In IAC-Caiapó, it was found AFB in 13% both in grains as in the shells samples, and CPA in 70% of the grains. The toxigenic potential results of A. flavus revealed 81% aflatoxins producers, 95% CPA producers and 75% both producers. All strains of A. flavus sclerotia producers belonged to the L group.
142

Engine Performance and Exhaust Emissions of a Diesel Engine From Various Biodiesel Feedstock

Santos, Bjorn Sanchez 2009 December 1900 (has links)
Increasing fuel prices, stricter government policies, and technological developments made it possible to seek for renewable alternatives, called biofuels, to petroleum fuel. Biodiesel, a biofuel that is produced from chemically mixing animal fat, vegetable oils, or recycled restaurant grease with alcohol and catalyst, is gaining popularity in recent years as a substitute for petroleum diesel. Ninety percent (90%) of U.S. biodiesel industry makes use of soybean oil as its feedstock. However, soybean oil alone cannot meet such a huge demand on biofuel production. Hence, it is important to identify and get more information about other feedstocks, specifically on its effects on the performance and exhaust emissions of diesel engines. The purpose of this study is to investigate the performance and emissions of two diesel engines operating on different biodiesel fuels (i.e. canola oil, sunflower oil, safflower oil, peanut oil, and chicken fat) and compare them to the performance and emissions when the engine is operated on soybean oil-based biodiesel and petroleum-based diesel. Results indicated that an engine operating on biodiesel generates a little less power and torque at any given speed than one running on diesel. Such power and torque loss were attributed to the biodiesel's lower energy content. The lower heating value (energy content) of biodiesel can be reflected in the specific fuel consumption, i.e., to generate the same power, more biodiesel is needed. The reduction in torque and power of less than 10% indicates that in some cases biodiesel has better combustion than diesel. Unfortunately, the high efficiency of combustion may give rise to increased combustion temperature which may lead to higher exhaust emissions. The gradual decrease in the total hydrocarbon and CO2 emissions, as blends were increased from B20 to B100, was also found to be an indication of better combustion using biodiesel fuels than petroleum diesel. However, NOx emissions were higher, predominantly at low speeds for most biodiesel and blends and therefore may require some additives or engine modifications/or adjustments to equalize the NOx emissions of diesel. Other emissions particularly SO2 were lower than standards require.
143

Composição botânica, estrutural, valor nutricional e dinâmica do nitrogênio em pastagens de azevém consorciadas / Botanic, structural composition and nutritional value and nitrogen dynamic on ryegrass pastures intercropped

Skonieski, Fernando Reimann 19 February 2009 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The utilization of leguminous plants as a mixing with grass is an economic and simple alternative for the increment of nitrogen on soil and plants, building up the sustainability of pasture systems. This work aimed to evaluate the different species plants consorted with ryegrass through the N incidence on pastures, regarding the MS accumulation, within an agro ecological transition system. The experimental pasture was established by the minimum tillage of the soil after doing two harrowing. It was evaluated in the annual ryegrass culture (Lolium multiflorum Lam.), cv. Common and its treatment was composed joining black oats, white clover and forage peanut. The first grazing was done 21 days after the plants emerge in the pastures of AZ+AV and AZ+AF and 28 days after emerging in the pasture of AZ+TB. The second grazing, at the AZ|+AV pasture, occurred 30 days after the first one, whereas to the others, it occurred 37 days after. The rates of MS accumulation, considering the period of exclusion until the MS production hit the top, was 77,7, 75 and 71kg/ha of MS/day for the pastures joint with AZ+TB, AZ+AF and AZ+AV, respectively. The relation between leaf and culm, until the first grazing, was raised in every experiment. The coefficient (β), which was used in all the pasture samples, was lower than -0,60; the highest N concentration declination in plant tissues, as a consequence of the MS accumulation, occurred in the AZ+TB (-0,94) pasture sample and in the AZ+AF and AZ+AV pastures on the sequence, respectively. The highest content of N, in the plant tissue, was found in the ryegrass only when it was mixed up with white clover. / A utilização de leguminosas em mistura com gramíneas é uma alternativa prática e econômica de incrementar nitrogênio no solo e planta, aumentando a sustentabilidade dos sistemas pastoris. O objetivo do trabalho foi avaliar diferentes espécies em consórcio com azevém sobre a composição botânica, estrutural, nutricional e a dinâmica do N nas pastagens, em um sistema de transição agroecológica. Foi avaliada a cultura do azevém anual (Lolium multiflorum Lam.), cv. Comum, sendo os tratamentos compostos pelos consórcios com aveia preta (Avena strigosa Schreb.), cv. Comum (AZ+AV), trevo branco (Trifollium repens L.), cv. Yi (AZ+TB) e amendoim forrageiro (Arachis pintoi Krapov. & Gregory), cv. Amarillo (AZ+AF). O delineamento experimental foi o inteiramente casualizado, com três tratamentos e três repetições. O 1º pastejo foi realizado com 21 dias após a emergência das plantas nas pastagens de AZ+AV e AZ+AF, e com 28 dias após a emergência na pastagem de AZ+TB. O 2º pastejo na pastagem de AZ+AV ocorreu 30 dias após o 1º pastejo, enquanto para as demais pastagens ocorreu 37 dias após. As taxas de acúmulo de MS considerando o período de exclusão até a produção de MS atingir o pico foi de 77,7, 75,0 e 71,3 kg/ha de MS/dia, para as pastagens consorciadas com AZ+TB, AZ+AF e AZ+AV, respectivamente. A relação folha/colmo até o primeiro pastejo foi elevada em todos os tratamentos. Em relação às curvas de diluição do N, o valor do coeficiente (β) em todas as pastagens foi menor que -0,60, o maior declínio da concentração de N no tecido vegetal em função do acumulo de MS ocorreu na pastagem de AZ+TB (-0,94), seguido das pastagens de AZ+AF e AZ+AV, respectivamente. O maior conteúdo de N no tecido vegetal foi observado no azevém quando consorciado com trevo branco.
144

PASTAGENS DE COASTCROSS-1 CONSORCIADA COM LEGUMINOSAS SOB PASTEJO / COASTCROSS-1 PASTURES MIXED WITH FORAGE LEGUME UNDER GRAZING

Machado, Paulo Roberto 25 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The objective of this research was to evaluate of three pasture-based systems with bermudagrass (BG) + 200 kg of N/ha; BG + 100 kg of N/ha and common vetch; BG + 100 kg of N/ha + forage peanut. The experiment was carried out from May 2011 to may 2012. Holstein cows receiving 4 kg-daily complementary concentrate feed were used in the evaluation. The actual mean value of forage on offer was 7.2 kg of dry matter/100 kg live weight. Herbage mass, botanical and structural composition, daily dry matter accumulation rate, forage production, disappearance of forage mass and stocking rate were evaluated. Nine grazing cycles were performed during the experimental period (365 days). The mean value of forage production and stocking rate were 21.05; 21.8 and 16.1 t/ha; 5.1; 5.3 and 4.5 animal units/ha/day for respective pasture systems. Superior result were found on BG + 100 kg of N/ha + common vetch and BG + 200 kg of N/ha pasture systems. / Objetivou-se com essa pesquisa avaliar três sistemas forrageiros constituídos por capim bermuda (CB) + 200 kg de N/ha; CB + 100 kg de N/ha e ervilhaca comum e CB + 100 kg de N /ha + amendoim forrageiro. O experimento foi realizado entre maio de 2011 e maio de 2012. Para avaliação foram utilizadas vacas em lactação da raça Holandesa, que receberam individualmente 4 kg/dia de concentrado. A oferta de forragem foi de 7,2 kg de matéria seca /100 kg de peso vivo. Foram avaliadas a massa de forragem, a composição botânica e estrutural, a taxa de acúmulo diário de matéria seca, a produção de forragem e o desaparecimento de massa de forragem e a taxa de lotação. Durante o período experimental (365 dias) foram realizados nove ciclos de pastejo. O valor médio da produção de forragem e a taxa de lotação foram de 21,05; 21,8 e 16,1 t/ha; 5,1; 5,3 e 4,5 unidades animais/ha/dia para os respectivos sistemas forrageiros. Resultados superiores foram encontrados nos sistemas forrageiros constituídos por CB+ 100 kg de N/ha + ervilhaca comum e CB + 200 kg de N/ha.
145

Distribuição espacial e amostragem sequencial de Stegasta bosquella (Chambers, 1875) (Lepidoptera: Gelechiidae) e Enneothrips Flavens Moulton, 1941 (Thysanoptera: Thripidae), em amendoim de porte rasteiro / Spatial distribution and sequential sampling Stegasta Bosquella (Chambers, 1875) (Lepidoptera: Gelechiidae) and Tripes do Prateamento, Enneothrips Flavens Moulton (Thysanoptera: Thripidae), in the peanut crop

Boiça Neto, Arlindo Leal [UNESP] 21 October 2016 (has links)
Submitted by ARLINDO LEAL BOIÇA NETO null (arlindoboica@gmail.com) on 2016-11-10T18:24:40Z No. of bitstreams: 1 Dissertacao_final (CORRIGIDA) com certificado de aprovação.pdf: 2125977 bytes, checksum: 3df4ff312236d23618c3631b2161a7d3 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO null (luizaromanetto@hotmail.com) on 2016-11-16T15:54:24Z (GMT) No. of bitstreams: 1 boica neto_al_dr_jabo.pdf: 2125977 bytes, checksum: 3df4ff312236d23618c3631b2161a7d3 (MD5) / Made available in DSpace on 2016-11-16T15:54:24Z (GMT). No. of bitstreams: 1 boica neto_al_dr_jabo.pdf: 2125977 bytes, checksum: 3df4ff312236d23618c3631b2161a7d3 (MD5) Previous issue date: 2016-10-21 / O amendoim é cultivado em vários estados no Brasil sendo São Paulo o maior produtor, seguido da Bahia e Mato Grosso. Semeadas em épocas diferentes conforme a região do cultivo, a área cultivada do amendoim na safra de 2014/15 no Brasil abrangeu uma área de 107,4 mil hectares, com uma produção média de 3140 kg ha⁻¹. Duas pragas destacam-se pela importância nessa cultura, sendo a lagarta-do-pescoço-vermelho, Stegasta bosquella (Chambers, 1875) (Lepidoptera: Gelechiidae) e o tripes-do-prateamento, Enneothrips flavens Moulton, 1941 (Thysanoptera: Thripidae) por causarem elevados prejuízos econômicos ao agricultor. Na literatura, poucas informações são relatadas de amostragens de pragas no amendoinzeiro. Assim, associando-se esse fato a importância das duas pragas na cultura do amendoim, se fez necessário um estudo por meio de modelos probabilísticos para avaliar as suas distribuições espaciais e amostragens sequenciais, gerando assim futuras informações aos agricultores para o manejo integrado de pragas nessa cultura. Os experimentos foram conduzidos nos anos de 2013/2014 e 2014/2015, em Jaboticabal – SP, utilizando uma área de 1,08 ha, subdividida em 100 parcelas iguais de 108 m² (10,0 x 10,8 m). Em cada parcela foram avaliadas cinco plantas ao acaso, considerando a presença ou não de insetos de S. bosquella e E. flavens. Pelos dados, observaram-se uma distribuição agregada ou moderadamente agregada de E. flavens e uma distribuição aleatória de S. bosquella; o modelo de distribuição que melhor se ajustou para E. flavens foi a binomial negativa e para lagartas de S. bosquella o modelo de distribuição de Poisson. Estes resultados permitiram a elaboração de planos de amostragem sequencial, na qual, tripes e lagartas apresentam duas retas: uma superior (S1 = 6,3072 + 1,0680 N), (S1 = 3,2134 + 0,3274 N), a partir da qual recomenda-se o controle; e outra inferior (S0 = -6,3072 + 1,0680 N), (S0 = -3,2134 + 0,3274 N), na qual, controle não é recomendado, respectivamente. Pelos resultados analisados, é possível verificar que a amostragem sequencial é eficiente na indicação ou não do controle de E. flavens e S. bosquella na cultura do amendoim. / The Peanuts are grown in several states in Brazil and São Paulo is the largest producer, followed by Bahia and Mato Grosso. Sown at different times as the growing region, the cultivated peanut area in 2014/15 crop in Brazil covered an area of 107,400 hectares, with an average production of 3140 kg ha⁻¹. Two pests stand out the importance that culture, and the red-necked peanut worm, Stegasta bosquella (Chambers, 1875) (Lepidoptera: Gelechiidae) and silvering thrips, Enneothrips flavens Moulton, 1941 (Thysanoptera: Thripidae) to cause high economic losses to the farmer. In the literature, little information is reported samplings pest in groundnut. Thus, associating this fact the importance of the two pests in peanut crop, a study using probabilistic models to assess their spatial and sequential sampling distributions made necessary, thus generating further information to farmers for the integrated pest management that culture. The experiments were conducted in the years 2013/2014 and 2014/2015, in Jaboticabal - SP, using an area of 1,08 ha, divided into 100 equal installments of 108 m² (10,0 x 10,8 m). In each plot were evaluated 5 randomly plants considering the presence or absence of E. flavens insects and S. bosquella. From the data, they observed an aggregate or aggregate distribution moderately E. flavens and a random distribution S. bosquella; the distribution model best fit for E. flavens was the negative binomial and larvae of S. bosquella the Poisson distribution model. These results allowed the development of sequential sampling plans in which, thrips and caterpillars have two lines: an upper (S1 = 6.3072 + 1.0680 N), (S1 = 3.2134 + 0.3274 N), the from which it is recommended to control; and bottom (S0 = -6.3072 + 1.0680 N) (S0 = -3.2134 + 0.3274 N), in which control is not recommended, respectively. The results analyzed, you can see that the sequential sampling is efficient in indicating whether or not the control E. flavens and S. bosquella the peanut crop.
146

Fungos, micotoxinas e fitoalexina em variedades de amendoim do plantio ao armazenamento. / Fungi, mycotoxins phytoalexin in peanut varieties, during plant growth from the field to storage.

Patricia Zorzete 07 December 2010 (has links)
O trabalho avaliou micobiota, contaminação por aflatoxinas (AFB), ácido ciclopiazônico (ACP) e fitoalexina (trans-resveratrol) nas variedades de amendoim Runner IAC 886 e IAC-Caiapó, no campo e armazenamento. Nas amostras de campo, na IAC 886 predominou Fusarium spp. nos grãos e cascas, contaminação por AFB em 30% dos grãos, ACP em 70% e trans-resveratrol em 5%. Na IAC-Caiapó prevaleceu Fusarium spp., em todas as amostras, AFB em 25% dos grãos, ACP em 55% e trans-resveratrol em 15%. Nas folhas, trans-reveratrol estava presente em 70%, nas variedades. No armazenamento, observou-se maior freqüência de A. flavus, A. parasiticus. Na IAC 886 AFB foi detectada em 20% nos grãos e 23% nas cascas e ACP em 80% dos grãos. Na IAC-Caiapó, AFB foi encontrada em 13% tanto nas amostras de grãos, como nas cascas e ACP em 70% dos grãos. Os resultados do potencial toxigênico de A. flavus revelaram 81% produtores de aflatoxinas, 95% de ACP e 75% de ambas. Todos A. flavus produtores de esclerócios pertenciam ao grupo L. / This study had assessed mycobiota, contamination by aflatoxins (AFB), cyclopiazonic acid (CPA) and phytoalexin (trans-resveratrol) in the peanuts varieties Runner IAC 886 and IAC-Caiapó, in the field and storage. In the Field samples, in IAC 886 it was predominated Fusarium spp. in grains and shells, contamination by AFB in 30% of the grains, CPA in 70% and trans-resveratrol in 5%. In IAC-Caiapó, it was prevailed Fusarium spp. in all samples, AFB in 25% of the grains, CPA in 55% and trans-resveratrol in 15%. In the leaves, trans-resveratrol was present in 70% in the varieties. In the storage, it was observed a higher frequency of A. flavus, A. parasiticus. In IAC 886, it was detected AFB in 20% of the grains and 23% in the shells, and CPA in 80% of the grains. In IAC-Caiapó, it was found AFB in 13% both in grains as in the shells samples, and CPA in 70% of the grains. The toxigenic potential results of A. flavus revealed 81% aflatoxins producers, 95% CPA producers and 75% both producers. All strains of A. flavus sclerotia producers belonged to the L group.
147

Strategies towards the synthesis of 4-(3-methyl-but-1-enyl)-3,5,3',4'-tetrahydroxystilbene (arachidin-1) and resveratrol analogues

Olusegun-Osoba, Elizabeth Oluwakemi January 2015 (has links)
Stilbene phytoalexins such as resveratrol, 1, and the arachidins, including arachidin-1,2, are naturally synthesised by peanut (Arachis hypogaea) plants. The peanut phytoalexins are polyphenolic compounds consisting of a stilbene backbone, with a number of derivatives also possessing a prenyl moiety. These distinctive phytoalexins have gained attention, as they exhibit various biological activities, for instance arachidin-1, 2, has been reported to be more potent than resveratrol, 1, in the inhibition of lipopolysaccharide-induced expression of cyclooxygenase-2 (COX-2) and COX-2 mRNA, in vitro at doses that were low in cytotoxicity. Additionally the various arachidins have recently been shown to exhibit their anti-inflammatory properties, through the inhibition of a number of inflammatory mediator pathways. In this work, various routes into the synthesis of arachidin-1, 2, are described, via use of the Horner-Wadsworth-Emmons (HWE) reaction. Three different methodologies were explored, the first approach involving silyl ether (TIPS or TBDMS) protected benzaldehydes, proved unsuccessful due to cleavage of the silyl ether protecting groups, in basic and/or acidic conditions. This led to an alternative approach, whereby formation of the stilbene backbone proceeded via the regioselective demethylation of an acetal in the presence of sodium metal, subsequent electrophilic substitution using iodomethane and finally acetal hydrolysis of the acetal, gave the isolated aldehyde in moderate yield (52 %). Coupling of the aldehyde with the substituted benzylphosphonate, via the HWE reaction gave the desired trans-stilbene in good yield (86 %), however incorporation of the prenyl side chain proved to be challenging via the Wohl-Ziegler bromination. Further adaptation of the aforementioned route, whereby alkylation using diethyl iodomethylphosphonate, enabled the incorporation of the prenyl moiety and the subsequent construction of the trans-stilbene backbone, gave the 4-(3-methyl-but-1- enyl)-3,5,3',4'-tetramethoxystilbene, 3, albeit in poor yield (47 %). The final step involving demethylation using BBr3 gave arachidin-1, 2, also in poor yield (30 %), nevertheless this approach has been proved to be a successful route for the total synthesis of arachidin-1, 2, however optimised studies are required in order to obtain the desired compound in quantitative yields. Synthetic analogues of resveratrol, 1, are also known for their biological activities, including anti-inflammatory and chemopreventative properties. Recently, the anti-proliferative activity of a number of stilbenesulfonamides, against the National Cancer Institute's 60 (NCI-60) human tumour cell line has been reported. Furthermore, the anti-inflammatory effects of novel heterocyclic methylsulfone and sulfonamide analogues, via inhibition of the COX-2 protein have also been published, however both synthetic routes described require a total of six or seven steps, from the sulfanilamide and are limited to the synthesis of primary sulphonamides (SO2NH2). In this work, an efficient three step synthesis has been designed and successfully implemented, proceeding via chlorosulfonation of diethyl benzylphosphonate, to form the sulfonyl chloride intermediate. Aminolysis of the sulfonyl chloride intermediate was then performed, using a range of primary, secondary and cyclic alkyl amines, as well as aromatic amines; including ammonia, dimethylamine, morpholine and diphenylamine. Finally, formation of the stilbene backbone with various substituted aldehydes, via the HWE reaction offered a short, versatile and alternative route to the synthesis of novel primary, secondary and tertiary trans-stilbene benzenesulfonamides and heterocyclic analogues, in yields of 42 - 100 %. The activity of a selection of the synthesised stilbene benzenesulfonamides was evaluated against the human lung adenocarcinoma epithelial cell line (A549). Amongst the compounds tested, analysis of the data showed that the novel analogue, 4, was found to be the most potent compound, with a GI50 of 0.1 μM. Comparison with the previously published data found analogue, 4, to be approximately 500-fold more potent than the lead compound resveratrol, 1, (GI50 = 51.64 μM) and approximately twice as potent than 5-fluorouracil (GI50 = 0.189μM), a chemotherapy drug used to treat various forms of cancer 8. Overall, these results demonstrate that the total synthesis of trans-arachidin-1, 2, can be achieved via a five step methodology. A versatile route to the synthesis of novel stilbene benzenesulfonamides has also been successfully achieved, amongst the compounds synthesised one appears to show promising anticancer activity, and warrants further investigation (i.e. in vitro studies using other cancer cell lines, and the synthesis of additional compounds using analogue, 4, as a lead compound).
148

Desempenho zootécnico e características físico-químicas da carne de vitelões Nelore e Limousin x Nelore criados sob sistema orgânico e submetidos a diferentes suplementações em cocho privativo / Performance and Physical Chemical Composition of "Vitelão" Nellore and Limousin x Nellore Meat Raised under Organic Conditions and Fed with Differents Creep Feeding

Fabiana Villa Alves 28 August 2007 (has links)
O objetivo deste trabalho foi avaliar o efeito da dieta, grupamento genético e sexo na produção de vitelões mantidos em pastagens de Brachiaria sp. e criados em Sistema Orgânico, analisando desempenho e características físico-químicas da carne. Cinqüenta e um bezerros Nelore e Limousin x Nelore foram suplementados em cocho privativo até a desmama. Os tratamentos foram: MSC, suplemento à base de milho+farelo de soja+ complexo mineral para lactentes; MSAC, suplemento à base de milho+farelo de soja+farelo de amendoim+ complexo mineral para lactentes; CMF, complexo mineral para lactentes. Após a desmama (aos 260 dias), os animais foram recriados à pasto, recebendo dois tratamentos (1 kg/animal/dia): MAP, ração à base de milho+farelo de soja e sal mineral à vontade; MASP, ração à base de milho+farelo de soja+farelo de amendoim e sal mineral à vontade. Foram mensurados o peso ao nascer (PN), peso de entrada no creep (PEC), peso de saída do creep (PSC), peso a desmama ajustado (PD), peso à fazenda (PFZ). Também foram determinados o ganho de peso do nascimento ao desmame (GNDA) e ganho de peso médio diário (GPMD). Os animais foram abatidos com idade média de 401 dias e PV médio de 227,75 kg. Após o abate, foram determinados o pH inicial (pH1) e peso da carcaça quente (PCQ). Após o resfriamento, determinaram-se o pH final (pH24), peso da carcaça fria (PCF), rendimento da carcaça fria (RC) e perdas por resfriamento (PR e PPR). Mensurou-se a área de olho de lombo (AOL) e espessura de gordura subcutânea (EGS) no Longissimus dorsi. Em amostras maturadas por 7 dias, foram avaliadas a cor (L*a*b*), perda de água por descongelamento (PAD), perda de água por cocção (PAC), perdas totais (PT) e força de cisalhamento (FC). Também se determinou o perfil dos ácidos graxos, colesterol e composição centesimal (CS) da carne. Houve interação entre sexo e grupo genético para PN (P<0,01); dieta e sexo para PCQ (P<0,05) e FC (P<0,01) e dieta, sexo e grupo genético para FC (P<0,05). Não foram observardas diferenças entre MSC, MSAC e CFM para nenhum dos caracteres até o abate. A EGS foi influenciada pela ração (P<0,01). O sexo influenciou PD (P<0,05), GPMD (P<0,01), GPDA (P<0,05), EGS (P<0,05) e CS (P<0,05), com exceção de matéria mineral. O grupamento genético, por sua vez, influenciou PEC (P<0,01), PD (P<0,01), GPM (P<0,01), GPDA (P<0,01), PSC (P<0,01), PFZ (P<0,01), PCQ (P<0,01), PCF (P<0,01), RC (P<0,05), PR (P<0,05), pH24 (P<0,01), AOL (P<0,01) e CS (P<0,05), com exceção de extrato etéreo e matéria mineral. Os resultados demonstraram que todas as suplementações podem ser utilizadas na produção de vitelões orgânicos sem detrimento ao desempenho e características físico-químicas da carne. Por outro lado, o grupamento genético, bem como o sexo do animal, podem influenciar características importantes dentro do Sistema de Produção. Em se tratando de produto orgânico, estudos adicionais devem ser realizados na tentativa de conciliar as exigências mercadológicas necessárias para comercialização e as normas exigidas para a sua produção. / The objective of this study was to evaluated the effect of creep fed, gender and breed on the performance and physical chemical composition of &#34;vitelão&#34; meat raised under organic condition on pastures of Brachiaria sp. Fifty one Nellore and Limousin x Nellore calves were fed until wean with different creep feeding: ground corn+soybean meal+special mineral complex for suckling calves (C1); ground corn+soybean meal+peanut meal+special mineral complex for suckling calves (C2); special mineral complex for suckling calves (C3). After weaning (260 days), the calves were maintained on pasture and distributed in two treatments: ground corn+soybean meal+ mineral salt (R1); ground corn+soybean meal+peanut meal+mineral salt. There were determinate the born weight (BW), initial creep weight (ICE), end creep weight (ECE), average daily gain (ADG), weaning weight (WW) and farm weight (FW). The animals were slaughtered at 401 days old and 227,75 LW. After slaughter, there were determinate the pH (pH1) and hot carcass weight (HCW). After cooling, there were determinate the parameters: cold carcass weight (CCW), carcass dressing (CD), ultimate pH (pH24) and refrigerated losses (RL). At 12th and 13th ribs on Longissimus dorsi were obtained rib eye area (REA), thickness of subcutaneous fat (TSF), shear force (SF), drip loss (DL), cooking loss (CL), instrumental colour (IC), fatty acid profile, cholesterol and chemical composition (CC). The results showed that there were not significant differences (P>0.05) between the diets for the parameters, except for TSF (P<0.01). The gender influenced the BW (P<0.05), ADG (P<0.01), TSF (P<0.05) and CC (P<0.05). The breed influenced the ICE (P<0.01), WW (P<0.01), ADG (P<0.01), ECE (P<0.01), FW (P<0.01), HCW (P<0.01), CCW (P<0.01), CD (P<0.05), RL (P<0.05), pH24 (P<0.01), REA (P<0.01), CC (P<0.05). The results showed that all diets can be use in &#34;vitelão&#34; system production without detriment of their performance or physical chemical characteristics. In despite of this, the gender and breed can influence important characteristics of the Production System. In organic foods, more study need to be done to conciliate the market requirements and the norms for Organic production.
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Alterações histológicas no epitélio intestinal de juvenis de dourado Salminus brasiliensis alimentados com dietas contendo fontes proteicas vegetais / Histological changes of intestinal epithelium of juveniles dourado Salminus brasiliensis fed diet with vegetables proteins sources alternatives

Thaline Maira Pachelli da Cruz 22 January 2018 (has links)
Restrições econômicas e ambientais trazem a necessidade de substituir a farinha de peixe em dietas de organismos aquáticos por matérias-primas menos dispendiosas de origem vegetal. Entretanto, tais fontes proteicas vegetais possuem fatores antinutricionais que podem ter efeitos negativos sobre o sistema digestório dos peixes, alterando a saúde e, em consequência, a produção. O objetivo deste trabalho foi avaliar a digestibilidade e alterações na histologia do epitélio intestinal de juvenis do Characiforme carnívoro dourado, Salminus brasiliensis, alimentados com dietas contendo farelo de soja (FSO), farelo de algodão (FAl) e farelo de amendoim (FAM) como principais fontes proteicas. Foram conduzidos dois experimentos: digestibilidade (Ensaio I) e histológico (Ensaio II). O Ensaio I foi conduzido em protocolo padrão utilizando dietas práticas adicionadas do marcador inerte óxido de crômio III (CR2O3) e sistema Guelph modificado para coleta de fezes e consequente cálculo dos coeficientes de digestibilidade. No Ensaio II as mesmas fonte proteicas - FSO, FAL e FAM - foram utilizadas em substituição à proteína da farinha de peixe em uma dieta controle com cinco níveis de inclusão: 0 (controle), 25,0 %; 50%; 75,0% e 100%, em um delineamento inteiramente aleatorizado (n=3). O experimento teve a duração de 40 dias, e as coleta de amostras de tecido foram feitas aos 20 e 40 dias. As amostras do intestino posterior foram analisadas quanto às características histológicas e morfológicas, além de quantificação de células caliciformes e análise histomorfométrica do tecido intestinal. Não foram registradas diferenças para os coeficientes de digestibilidade da proteína e energia no ensaio de digestibilidade. O ensaio de desempenho mostrou que a inclusão de FAM e FAL nas dietas melhora o consumo de alimento comparativamente ao FSO Em relação as variáveis histológicas, os níveis que condicionaram alterações significativas nos parâmetros morfométricos foram FSO50 e FOS75. O FSO50 promoveu uma redução das dobras intestinais aos 20 dias, porém aos 40 dias houve aumento na altura das dobras, no espessamento da lâmina-própria e aumento na densidade das células caliciformes. Considerando a microscopia de varredura, sinais acentuados de enterite foram registrados. A alteração na morfologia e histologia do epitélio intestinal foi reflexo da interação de efeitos dos fatores antinutricionais presentes em cada fonte proteica vegetal. Consequentemente, registrou-se menor ganho de peso, crescimento e diminuição da homeostase intestinal, embora os melhores consumos e CAA fossem registrados para os peixes alimentados com FAL e FP. Conclui-se que o FSO causou enterite nos juvenis de dourado e FAL e FAM podem ser utilizados na alimentação de dourado. / Economic and environment constraints have brought the need to replace fishmeal (FM) in diets of aquatic organisms by less expensive feedstuff, especially dietary protein sources. However, such protein sources generally of plant origin, e.g. soybean meal, have antinutritional factors that can negatively affect digestive system of the fish, impairing health and consequently, production. To identify possible effects of plant protein sources in the diets for carnivore fish, this study evaluated effects of various dietary plant protein sources on digestibility, performance, histology of the intestinal epithelium of the carnivore, Neotropical Characin dourado, Salminus brasiliensis, fed plant protein-based diets. A digestibility trial was carried out in standard protocol using diets with inert marker chromium oxide III (Cr2O3) and modified system Guelph for feces. A performance test evaluated the use of three plant protein sources, soybean meal (SBM), cottonseed meal (CTM) and peanut meal (PTM) as surrogate protein source to fishmeal in a practical diet in five levels inclusion: 0 (control); 25.0%; 50.0%; 75.0% and 100%, in a randomized block design (n=3). Samples of tissue of intestinal tract of fish were collected in the distal segment at 20 and 40 days of the feeding period, and analyzed for histological and morphological characteristics. No differences were recorded for apparent digestibility coefficients (ADC) of feedstuff and energy and protein of feedstuffs. Dietary CM and PM elicited better feed consumption comparatively to the other feedstuff, Fish fed diet diet SBM50 presented reduction of intestinal folds at 20 days, but at 40 days had increased folds height, lamina propria thickening, and increased goblet cell density. Considering a scanning microscopy, evident signs of enteritis were registered. The alteration in the morphology and histology of the intestinal epithelium reflected the interaction of effects of the antinutritional factors present in each vegetable protein source, resulting in lower weight gain, growth and decreased intestinal homeostasis, even though best feed consumption and ADC were registered for fish fed CTM and FM.Concluded that SBM caused enteritis and CTM and PM can be used in feeding dourado.
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Desempenho, características de carcaça e parâmetros metabólicos de cordeiros recebendo rações ricas em amido e fontes protéicas / Performance, carcass characteristics and metabolic parameters of lambs fed protein sources in starch rich diets

Mário Adriano Ávila Queiroz 02 April 2008 (has links)
Fontes protéicas em rações ricas em amido foram avaliadas para cordeiros em confinamento. O primeiro aspecto foi investigar a variação do consumo de matéria seca (MS) de 28 cordeiros da raça Santa Inês; o ganho de peso médio diário (GMD), as características de carcaça e da carne e o custo dos alimentos. O delineamento foi em blocos completos casualizados, sendo as dietas isonitrogenadas, com 90% de concentrado e 10% de feno de coastcross. As rações foram formuladas pelo Small Ruminant Nutrition System (SRNS) versão 1.8.1 e diferiam quanto à fonte suplementar de proteína: farelo de soja, farelo de amendoim, farelo de canola, farelo de algodão. O segundo aspecto avaliado foi o ensaio metabólico com quatro borregos fistulados no rúmen distribuídos em delineamento em quadrado latino 4x4 sendo analisadas as características físicas de capacidade de retenção de água (CRA), solubilidade, tamanho médio de partículas e densidade das fontes protéicas relacionados com a degradabilidade ruminal e a taxa de passagem. A contaminação de nitrogênio microbiano na degradabilidade da proteína das rações totais foi corrigida pelo nitrogênio insolúvel em detergente neutro (NIDN). Determinou-se a digestibilidade dos nutrientes no trato digestório total, o balanço de nitrogênio, as concentrações de nitrogênio amoniacal (N-NH3), ácidos graxos de cadeia curta (AGCC), o pH ruminal e a síntese de proteína microbiana. Adicionalmente, o teor de amido nas fezes foi avaliado como indicador para estimar a digestibilidade do amido das rações. Como último aspecto estudado, confrontou-se os dados metabólicos e de desempenho obtidos no ensaio experimental com as estimativas obtidas no SRNS. As fontes protéicas não alteraram (P>0,05) os parâmetros de desempenho e as características de carcaça e da carne. A solubilidade e a CRA influenciaram (P<0,05) a degradabilidade efetiva da MS. A ração com o farelo de algodão apresentou menor (P<0,05) degradabilidade efetiva da proteína bruta o que refletiu em maior (P<0,05) excreção de nitrogênio nas fezes. A contaminação microbiana subestimou a taxa de degradação da ração total em aproximadamente 13,5%. O farelo de canola apresentou menor taxa de passagem (P<0,05) e o principal parâmetro físico relacionado com essa variável foi a CRA. A ração com o farelo de amendoim promoveu menor custo de nitrogênio por kg de ganho, maiores concentrações de (N-NH3) e menores proporções de (AGCC) (P<0,05), porém, a síntese de nitrogênio microbiano e a excreção de nitrogênio na urina foram semelhantes (P>0,05) entre os tratamentos. O teor de amido fecal mostrou-se eficiente como indicador na estimativa da digestibilidade do amido com coeficiente de determinação de 93%. As estimativas de desempenho e metabólica do sistema SRNS foram satisfatórias com algumas diferenças (P<0,05) na ingestão de MS e na taxa de passagem. Os resultados apresentados poderão contribuir com o banco de dados de sistemas de formulação de rações para ovinos em crescimento. / Protein sources in starch rich diets for finishing lambs were evaluated in this study. Twenty-eight Santa Ines ram lambs were used to determine the effects of using different protein sources in dry matter intake, average daily gain and characteristics of carcass and meat. Lambs were assigned, by weight and age at the beginning of the trial, in a complete randomized block design. Experimental diets were isonitrogen with 90% concentrate and 10% coastcross hay. Rations were formulated using the Small Ruminant Nutrition system (SRNS) version 1.8.1 and had one of the following protein sources: soybean meal, peanut meal, canola meal or cottonseed meal. A metabolism assay using a Latin square 4 x 4 design also was performed. Four rumen cannulated wethers were used to determine protein sources physical characteristics: water holding capacity (WHC), solubility, mean particle size and density in relation with ruminal degradability and rate of passage. Microbial nitrogen contamination of TMR was corrected by in neutral detergent fiber insoluble nitrogen. Total tract diet digestibility, nitrogen balance, ammonia nitrogen concentration (N-NH3), short chain fatty acids, ruminal pH and microbial protein synthesis were determined. In addition, fecal starch concentration was evaluated as an indicator to estimate starch digestibility in the ration. Performance and metabolic data were compared to SRNS estimates. Protein sources did not affected performance or carcass and meat characteristics. Water holding capacity and solubility affected (P<0.05) DM effective degradability. Cottonseed diet resulted in lower (P<0.05) CP effective degradability showing higher (P<0.05) excretion of fecal N. Microbial contamination underestimated diet degradation in 13.5%. Canola meal diet had the lower rate of passage and the main physical parameter related with this variable was water holding capacity. Peanut meal diet had high concentration of NNH3 and the lowest short chain fatty acids concentration. However, microbial N synthesis and excretion of N in urine were similar among treatments. Fecal starch concentration was a good indicator to estimate starch digestibility showing a coefficient of determination of 93%. Estimates from SRNS for DM intake and rate of passage were different from observed data. There results may contribute to predict nutrient requirements and biological value of feeds for lambs.

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