Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-20T11:02:31Z No. of bitstreams: 2 Dissertação - Aline de Souza Silva Cunha - 2018.pdf: 1062185 bytes, checksum: 7795471b2795e517792143e4b1509777 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-03-20T11:04:49Z (GMT) No. of bitstreams: 2 Dissertação - Aline de Souza Silva Cunha - 2018.pdf: 1062185 bytes, checksum: 7795471b2795e517792143e4b1509777 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-20T11:04:49Z (GMT). No. of bitstreams: 2 Dissertação - Aline de Souza Silva Cunha - 2018.pdf: 1062185 bytes, checksum: 7795471b2795e517792143e4b1509777 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-26 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / The aim was to evaluate the protective effect of dietholate on selectivity of clomazone herbicide in forage grasses (Urochloa brizantha cv. Marandu, Urochloa ruziziensis, Urochloa humidicola, Panicum maximum cv. Mombaça and cv. Massai). The experimental design was carried out in randomized blocks, and the treatments were arranged in a 5 X 3 factorial scheme with, 4 repetitions. The first factor corresponded to safener doses applied to the seeds (0, 600, 1200, 2400 e 3000 mL 100 kg-1 of seeds) and the second factor corresponded to the clomazone herbicide doses (0,720 and 1440 g i.a ha-1). It was evaluated the following aspects: visual injury levels within 7, 14 and 28 days after emergency (DAE), tiller number and volumetric density of dry matter (VDDM). Dietholate provides protection to the phytotoxic effects of clomazone herbicide on the species Urochloa brizantha cv. Marandu, Urochloa humidicola and Urochloa ruziziensis, at doses of 600, 1.200 and 2.400 mL 100 kg-1 of seeds. The utilization of safener on the species Panicum maximum cv. Mombaça and Massai shows protective activity specially at doses of 600 and 1.200 100 kg-1 of seeds. The results for injury on the plants indicate significant importance of dietholate as seed safener, for the use of clomazone herbicide on pasture areas. / Objetivou-se avaliar o efeito protetor do dietholate na seletividade do herbicida clomazone em gramíneas forrageiras (Urochloa brizantha cv. Marandu, Urochloa ruziziensis, Urochloa humidicola, Panicum maximum cv. Massai e Mombaça). O delineamento experimental foi estabelecido em blocos casualizados, e os tratamentos dispostos em esquema fatorial 5 x 3, com quatro repetições. O primeiro fator correspondeu às doses do protetor aplicadas às sementes (0, 600, 1,200, 2400 e 3000 mL 100 kg de sementes-1) e o segundo fator correspondeu às doses do herbicida clomazone a 0, 720 e 1440 g i.a. ha-1. Foram avaliados níveis de injúria visual aos 7, 14 e 28 dias após a emergência (DAE), número de perfilhos e densidade volumétrica de matéria seca (DVMS). O dietholate apresenta proteção aos efeitos fitotóxicos do herbicida clomazone sobre as espécies Urochloa brizantha cv. Marandu, Urochloa humidicola e Urochloa ruziziensis nas doses de 600, 1.200 e 2.400 mL 100 kg-1 sementes. Para as espécies Panicum maximum cv. Mombaça e Massai a utilização do safener exibe atividade protetora principalmente nas doses de 600 e 1.200 mL 100 kg-1 sementes. Os resultados de injúria sobre as plantas indicam importância significativa do dietholate como protetor de sementes, para o uso do herbicida clomazone em áreas de pastagens.

Submitted by Luanna Matias (lua_matias@yahoo.com.br) on 2015-02-04T19:08:20Z No. of bitstreams: 3 Tese - Pablo Santana Santos - 2014 - Parte 01.pdf: 5282585 bytes, checksum: fab627afa4b6a3b55752f51b90659610 (MD5) Tese - Pablo Santana Santos - 2014 - Parte 02.pdf: 3067324 bytes, checksum: d46d29a129169e109e2f94a8068ec633 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-02-05T09:54:10Z (GMT) No. of bitstreams: 3 Tese - Pablo Santana Santos - 2014 - Parte 01.pdf: 5282585 bytes, checksum: fab627afa4b6a3b55752f51b90659610 (MD5) Tese - Pablo Santana Santos - 2014 - Parte 02.pdf: 3067324 bytes, checksum: d46d29a129169e109e2f94a8068ec633 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-02-05T09:54:10Z (GMT). No. of bitstreams: 3 Tese - Pablo Santana Santos - 2014 - Parte 01.pdf: 5282585 bytes, checksum: fab627afa4b6a3b55752f51b90659610 (MD5) Tese - Pablo Santana Santos - 2014 - Parte 02.pdf: 3067324 bytes, checksum: d46d29a129169e109e2f94a8068ec633 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-05-15 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The agricultural expansion in the Brazilian Cerrado represents nowadays more than half of the total biome area, where conversion of the natural vegetation to pasturelands is the main dynamics imposed by the productive sector along the relatively recent historical occupation process. Such transformations tend to create distinct spatial patterns regarding the biophysical behavior of the main existent vegetation formations, which can be identified and discriminated through a variety of available remote sensing products. This study, focused on the rio Vermelho watershed, a representative unit of the Cerrado biome, and considering a variety of satellite data for the 2001 – 2011 period, pursued a detailed analysis of the biophysical responses in face of the historical processes that determined and shaped the landscape transformations. Specifically, the following datasets were utilized: MODIS (vegetation index, evapotranspiration and primary productivity) and TRMM (Tropical Rainfall Measurement Mission) precipitation. Our results indicated that climatic factors, such as seasonality, have a direct influence on biomass levels of key vegetation formations, particularly those with shallow root systems, for which reductions in radiometric values, as high as 50%, could be observed during the dry season. In fact, natural vegetation areas, comparatively to areas dominated by cultivated pastures, show very distinct and significant biophysical behavior (p < 0.05). Likewise, two major landscapes could be identified, i.e. “Region 1” and “Region 2”, where converted and remnant vegetation areas predominate, respectively. The distribution of natural and cultivated pastures seems to be related to local edafoclimatic factors, such as soil (depth/lithic content) and water availability, which explain the occurrence of most grass species. Based on field biomass, it is possible to say: 1) cultivated pastures found in “Region 1” are slightly more productive comparatily to those from “Region 2” (for both dry- and wet-seasons) and 2) there is a correspondence between “natural” and “cultivated” green biomass during the dry season, as opposed to the wet season. However, and based on the seasonal moderate spatial resolution MODIS images, it is not possible to separate between natural and cultivated pastures. In fact, such separation can be accomplished via the supervised classification (Support Vector Machine) of medium spatial resolution imagery (Landsat). Based on high spatial resolution (5m) RapidEye/BlackBridge images, it was produced a land cover / land use map for the entire basin at the 1:50.000 scale, in which it was possible to discriminate the major converted and natural physiognomies, and distinct grass species, in particular (Overall Accuracy ~ 90% and Kappa = 0.83). / A expansão da atividade agropecuária no Cerrado brasileiro representa hoje mais da metade da área total deste bioma, onde a conversão das áreas naturais em pastagens cultivadas foi a principal dinâmica imposta pelo setor produtivo ao longo de um processo histórico de ocupação relativamente recente. Tais transformações tendem a resultar em padrões espaciais distintos quanto ao comportamento biofísico das principais formações vegetais existentes, os quais podem ser identificados e discriminados através dos vários produtos de sensoriamento remoto disponíveis. O presente trabalho, ao utilizar a bacia hidrográfica do rio Vermelho como unidade experimental do bioma Cerrado, teve como objetivo principal realizar uma análise detalhada das respostas biofísicas frente aos processos históricos que condicionaram as transformações na paisagem, considerando o período entre 2001 a 2011, e uma ampla base de dados satelitária, obtida a partir dos produtos MODIS (índice de vegetação, evapotranspiração, produtividade primária) e TRMM (Tropical Rainfall Measurement Mission/precipitação). Os nossos resultados evidenciam que fatores climáticos, a exemplo da sazonalidade, tem uma influência direta na biomassa das principais formações vegetais, principalmente àquelas que apresentam sistemas radiculares superficiais, com reduções nos valores radiométricos de até 50% durante o período da seca. De forma significativa, as áreas de vegetação natural, comparadas às áreas de pastagens cultivadas, apresentaram comportamentos distintos do ponto de vista biofísico (p < 0,05). Em fato, dois macroambientes puderam ser definidos para a área de estudo, onde predominam a ocupação antrópica (“Região 1”) e a vegetação natural remanescente (Região 2), respectivamente. A distribuição das pastagens cultivadas e naturais está associada a fatores edafoclimáticos locais, como características de solo (profundidade/pedregosidade) e disponibilidade hídrica, os quais explicam a ocorrência da maioria das espécies forrageiras. Com base nos dados de biomassa coletados em campo, é possível afirmar: 1) as pastagens cultivadas encontradas na “Região 1” são ligeiramente mais produtivas do que as encontradas na “Região 2”, tanto no período seco quanto chuvoso, e 2) há uma correspondência entre a biomassa verde encontrada no período seco para as duas categorias de pastagens, ao contrário do observado no período chuvoso. Entretanto, e tendo por base as imagens biofísicas sazonais de resolução espacial moderada (MODIS), não é possível separar entre pastagens nativas e cultivadas. Por sua vez, esta separação se mostra possível através da classificação supervisionada (Support Vector Machine) de imagens de resolução espacial média (Landsat). Com base em imagens RapidEye/BlackBridge, com resolução espacial de 5m, foi produzido um mapa de cobertura e uso da terra à escala de 1:50.000, no qual foi possível separar as áreas de pastagens quanto à sua tipologia, bem como individualizálas em outras formas de uso e fito-fisionomias remanescentes (Acurácia Total ~ 90% e Kappa = 0,83).

Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-16T11:23:00Z No. of bitstreams: 2 Dissertacao2010_Ver__nica_Alves.pdf: 2047141 bytes, checksum: 188da6053334ff8142f1e9e0ec5f6e45 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-16T13:35:47Z (GMT) No. of bitstreams: 2 Dissertacao2010_Ver__nica_Alves.pdf: 2047141 bytes, checksum: 188da6053334ff8142f1e9e0ec5f6e45 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-16T13:35:47Z (GMT). No. of bitstreams: 2 Dissertacao2010_Ver__nica_Alves.pdf: 2047141 bytes, checksum: 188da6053334ff8142f1e9e0ec5f6e45 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2010-02-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The objective of this trial was to evaluate the productive and economic performance of dairy crossbred steers, reared on Brachiaria Brizantha pasture that received two levels of energetic supplementation during wet/dry transition and four levels during dry/wet transition seasons. During the wet season, forty-eight milk crossbred steers (Holstein x Zebu), with initial average weight of 123 kg and average age of 10 months were used. The treatments consisted of two levels of energy supplementation, 1% of BW, considered high, and 0.5% of BW, considered medium. During dry season, fortyfour fourteen-month-old milk crossbred steers (Holstein x Zebu) were used. The treatments consisted of two high levels of concentrate (1.6% and 1% of BW) and two medium levels of concentrate (0.8% and 0.5% of BW). The supplementation was composed of ground corn and mineral mixture, with urea addition during dry season. A completely randomized experimental design was used. The means were compared by F test at 5% probability in the first experiment and by Tukey test in the second one. The data were analyzed by SAS (1997). The average daily weight gain and final weight were similar between treatments in wet/dry transition. The thoracic measurement indicates a good ponderal development. Energetic supplementation of crossbred milk steers was economically viable, and the medium level (0.5% of BW) presented higher profitability than the high level (1% of BW). In dry season, the energy supplementation improved daily weight gain and the body measures of growing milk crossbred steers reared on pasture. Body length and scrotal perimeter indicated better body development. Milk crossbred steers supplemented on pasture with energy levels ranging from 0.5 to 1.6% should be commercialized for the price of live animal. And, in this case, the lowest level of supplementation (0.5% of BW) should be used for better profitability. / Objetivou-se avaliar o desempenho produtivo e econômico de novilhos de origem leiteira, suplementados com dois níveis de suplementação energética em pastagem de Brachiaria brizantha durante o período de transição águas/seca e a quatro níveis de suplementação energética durante o período de transição seca/águas. No período águas/seca foram utilizados 48 novilhos mestiços holandês x zebu, nãocastrados, com pesos médios iniciais de 123 kg e média de idade de 10 meses. Os tratamentos consistiram em dois níveis de suplementação energética, 1% do PV NA, considerado como nível alto e 0,5% do PV NM, considerado como nível médio. No período seca/águas foram 44 novilhos, não-castrados com 14 meses de idade e peso médio inicial de 183 kg. Os tratamentos consistiam de dois níveis altos de concentrado (1,6% e 1% do PV) e dois níveis médios de concentrado (0,8% e 0,5% do PV). O suplemento fornecido era composto por fubá de milho e mistura mineral. Na seca/águas adicionou-se uréia no suplemento. Utilizou um delineamento inteiramente casualizado e as médias foram comparadas pelo teste F para o primeiro experimento e Teste Tukey no segundo. Os dados foram analisados pelo SAS (1997). O ganho de peso médio diário e peso final foram similares entre tratamentos na transição águas/seca. Perímetro torácico representou bom indicativo de desenvolvimento ponderal. A suplementação energética de bovinos mestiços de origem leiteira mostrou-se economicamente viável, sendo que o nível médio (0,5% do PV) apresentou lucratividade superior comparado com o nível alto (1% do PV). No período seca/, a suplementação energética melhorou o ganho em peso e as medidas corporais de bovinos mestiços de origem leiteira em crescimento mantidos a pasto. Perímetro escrotal e comprimento representaram bom indicativo de desenvolvimento ponderal. Mestiços de origem leiteira suplementados a pasto com níveis variando de 0,5 a 1,6% de suplementação energética devem ser comercializados pelo preço de animal vivo. E quando a comercialização for feita dessa forma, recomenda-se utilizar o menor nível de suplementação (0,5% do PV) para se obter maior lucratividade.

Made available in DSpace on 2016-04-28T20:15:31Z (GMT). No. of bitstreams: 1 2008 - Simone Quinelato final.pdf: 1288089 bytes, checksum: 806c125a6ebd7474f17e8efb57adbc3f (MD5) Previous issue date: 2008-02-29 / The knowledge of biology and epidemiology of cyathostomin free living stages have been helping the development of control programs that limitis anthelmintic use. However little is known about environmental larvae dynamics, mainly in tropical climate. Studies about pasture contamination can help to estimate parasitic risks for animals and to set up integrate control programs. The present study was elaborated in three complemented parts: first, it was evaluated the distribution, recovery and survival of cyatostomin infective larvae of equines in feces and pasture during 15 months. Fecal samples were monthly placed on Tifton 85 (Cynodon spp. cv. Tifton 85) pasture, from september of 2003 to september of 2004. Grass and feces were collected weekly, at 8 a.m., 1 and 5 p.m. and processed by Baermann technique. The results indicate that the environmental conditions were favorable for L3 development and survival. In feces, more L3 was recovered during the rainy period and on the grass in dry period. L3 survival was higher in the dry period for feces and grass samples. L3 were recovered during the three times of collection and no significant difference was observed among three times. The second part was more wide-ranging and approaches the distribution, recovery and survival of cyathostomin infective larvae in feces and pasture for february 2005 to march 2007. Seven days after the deposit, sample of feces and grass were collected weekly at 8 a.m., 1 p.m. and 5p.m., from three different field sites. Grass sample was divided into base (0-20 cm) and apex (20-40 cm). The samples were processed by the Baermann technique for L3 recovery. In the rainy period, more infective larvae were recovered on the feces and grass apex. In the dry period, the recovery was higher only on the grass base, as well as the L3 survival on feces and grass. More larvae were recovered at 8 a.m., except from the grass apex, where the highest recovery was at 1 p.m. The third part refers to the seasonal distribution and recovery of cyathostomin infective larvae in feces, pasture and soil. In the beginning of the seasons feces samples were placed on experimental Tifton 85 plot. The collections began one week after deposit, and later every 15 days. L3 recovered were higher in the autumn and winter and smaller in the spring and mainly in the summer. More L3 were recovered in the morning, although no statistic difference has been observed between the collection times in each season. The soil didn't demonstrate to be potential L3 reservoir, seen the low larvae recovery in this study. / O conhecimento da biologia e epidemiologia das fases pr?-paras?ticas de ciatostom?neos de eq?inos t?m contribu?do para o desenvolvimento de programas de controle que limitem a utiliza??o de anti-helm?nticos. No entanto, pouco se conhece sobre a din?mica das larvas no ambiente, principalmente nas regi?es de clima tropical. Estudos sobre o grau de contamina??o das pastagens por larvas infectantes de ciatostom?neos podem auxiliar na determina??o do risco de infec??o dos animais e fornecer dados para o estabelecimento de programas de controle integrado. O presente estudo foi dividido em tr?s etapas complementares: na primeira etapa, avaliou-se a distribui??o, recupera??o e sobreviv?ncia de larvas infectantes (L3) de ciatostom?neos de eq?inos nas fezes e na pastagem no per?odo de 15 meses. Massas fecais foram depositadas mensalmente na gram?nea Tifton 85 (Cynodon spp. cv. Tifton 85) no per?odo de setembro de 2003 a setembro de 2004. Gram?nea e fezes foram coletadas a cada sete dias, ?s 8, 12 e 17h e processadas pela t?cnica de Baermann. De acordo com os resultados, as condi??es ambientais foram favor?veis para o desenvolvimento e sobreviv?ncia das L3. Nas fezes, a recupera??o das L3 foi superior durante o per?odo chuvoso e na gram?nea no per?odo seco. A sobreviv?ncia das larvas foi superior no per?odo seco, tanto para as amostras de fezes quanto para as de gram?nea. As L3 foram recuperadas durante os tr?s hor?rios de coleta e n?o se observou diferen?a significativa entre os hor?rios. A segunda etapa foi mais abrangente e aborda o estudo da distribui??o, recupera??o e sobreviv?ncia de larvas infectantes de ciatostom?neos de eq?inos nas fezes e na pastagem no per?odo de fevereiro de 2005 a mar?o de 2007. Sete dias ap?s cada dep?sito de massa fecal foram realizadas coletas de amostras de fezes e gram?nea ?s 8, 13 e 17 h, de tr?s pontos distintos em sentido hor?rio. As amostras de gram?nea coletadas foram divididas em base (0-20 cm) e ?pice (20-40 cm), tendo sido processadas pela t?cnica de Baermann para recupera??o das L3. No per?odo chuvoso, as larvas infectantes foram recuperadas em maior n?mero das fezes e do ?pice da gram?nea. No per?odo seco, a recupera??o foi superior na base da gram?nea, assim como a sobreviv?ncia das L3 nas fezes e na gram?nea. Maior n?mero de larvas foi recuperado ?s 8 h, exceto na base da gram?nea, onde a maior recupera??o de L3 ocorreu ?s 13 h. A terceira parte refere-se ? distribui??o sazonal e recupera??o de larvas infectantes de ciatostom?neos nas fezes, na pastagem e no solo. Ao in?cio de cada esta??o do ano foram depositadas amostras de fezes no canteiro experimental de Tifton 85. As coletas iniciaram-se uma semana ap?s o dep?sito e posteriormente a cada 15 dias. As L3 foram recuperadas em maior quantidade no outono e inverno e em menor quantidade na primavera e principalmente no ver?o. No hor?rio da manh? as larvas foram recuperadas em maior n?mero, embora n?o tenha sido observada diferen?a estat?stica entre os hor?rios de coleta em cada esta??o do ano. O solo n?o demonstrou ser potencial reservat?rio de L3, visto a baixa recupera??o de larvas neste estudo.

Submitted by Leticia Schettini (leticia@ufrrj.br) on 2016-10-04T14:27:06Z No. of bitstreams: 1 2005 - Ricardo Martinez Tarr?.pdf: 741184 bytes, checksum: 1a3cc666f5aa519958cd7cacafdbd30f (MD5) / Made available in DSpace on 2016-10-04T14:27:06Z (GMT). No. of bitstreams: 1 2005 - Ricardo Martinez Tarr?.pdf: 741184 bytes, checksum: 1a3cc666f5aa519958cd7cacafdbd30f (MD5) Previous issue date: 2005-03-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior-CAPES / The experiment was conducted at the Experimental Station of CEPLAC, located in the South of Bahia State (CEPLAC/CEPEC/ESSUL), set as a entirely randomized design with 6 treatments and 3 repetitions. The treatments consisted of 2 pastures, one of grassonly Brachiaria humidicola (Rendle) Schweickt, and the other of B. humidicola consorted with Desmodium ovalifolium Wall cv. Itabela, each grazed at 3 different stocking rates of 2, 3 and 4 animals per hectare. Estimates of animal intake under grazing were made at two occasions during the year (August and November of 1995). Six oesophagus-fistulated steers were used for sampling of the consumed forage, and 36 animals were fed with 10 g of Cr2O3 each day, for 21 days. The ?in vitro? digestibility of dry matter, total nitrogen, and natural abundance of 13C were analyzed in the fistula samples. At the same time, the productivity of the pastures and their botanical composition was measured. The presence of the legume D. ovalifolium in the pastures of B. humidicola increased the protein content of the forage ingested by the animals by 64%. The dry matter intake was affected negatively by the presence of the legume due to its low palatability, however the proportion of the legume in the diet was quite significant (27 to 62%), being highest in the higher stocking rates due to the more restricted selectivity of the grazing animals. At the lower stocking rate there was a larger proportion of the legume in forage on offer. The total protein intake by the animals was higher in mixed pastures, but that didn't provide a better animal performance due to low digestibility of the legume. The rate of decomposition was very rapid (k ~ -0.081 and 0.060g g-1 day-1) P and K, and annual rates of P turnover through the litter pathway were between 13.7 and 13.2 kg P ha-1 year-1. In the grass-only pastures, as stocking rate increased from 2 to 3 head ha-1, P recycled in the litter decreased by 11%, but a further increase to 4 head ha-1 decreased P recycling by 6%, suggesting that beyond a certain critical level higher grazing stocking rates would lead to pasture decline if there was no N addition. High stocking rates decreased proportion of the legume in the sward, but at all rates the concentration of P in both the green and dead grass, in the forage on offer and in the litter, was higher in the mixed sward. The presence of legume in the litter resulted in increases in P and K recycled via litter deposition varying from 12.5 to 14.3 kg P ha-1 year-1 and 25.0 to 37.6 kg K ha-1 year--1. / Esse experimento foi conduzido na Esta??o Experimental de Zootecnia do Extremo Sul da Bahia (ESSUL/CEPEC/CEPLAC) obedecendo a um delineamento experimental inteiramente casualizado, com 6 tratamentos e 3 repeti??es. Os tratamentos foram estabelecidos segundo um fatorial 2 x 3, com 2 pastagens, Brachiaria humidicola (Rendle) Schweickt em monocultura e B. humidicola consorciada com Desmodium ovalifolium Wall cv. Itabela, e 3 taxas de lota??o, 2, 3 e 4 cabe?as por hectare. A estimativa do consumo animal em pastejo foi avaliada em 2 ?pocas do ano (agosto e novembro de 1995). Utilizaram-se 6 animais bovinos es?fago-fistulados para a retirada das extrusas (dietas consumidas) e 36 bovinos foram dosados com 10 g de Cr2O3 por dia, durante 21 dias. A digestibilidade ?in vitro? da mat?ria seca e a abund?ncia natural do 13C foram analisadas nas extrusas. Paralelamente, foram avaliadas a produtividade das pastagens e a sua composi??o bot?nica. O consumo de mat?ria seca foi afetado negativamente pela presen?a da leguminosa D. ovalifolium nas pastagens de B. humidicola devido ? sua baixa palatabilidade, por?m a propor??o da leguminosa na dieta consumida foi bastante significativa, sendo maior nas taxas de lota??o mais elevadas onde a seletividade dos animais foi mais restrita, apesar do fato de que na menor taxa de lota??o havia uma maior propor??o da leguminosa na forragem em oferta. O menor consumo de forragem observado nas pastagens consorciadas, n?o proporcionou menor desempenho animal, provavelmente devido ? maior oferta de prote?na oferecida pela leguminosa. As altas taxas de lota??o provocaram uma diminui??o na propor??o de leguminosas na forragem em oferta, entretanto em todas as taxas de lota??o a concentra??o de P na gram?nea verde e seca da forragem em oferta e da liteira foi maior nas pastagens consorciadas. A taxa de decomposi??o da liteira foi muito elevada, cerca de 0,081 e 0,060 g g-1 dia-1, para P e K respectivamente, acarretando uma deposi??o anual de P pela liteira entre 13,2 e 13,7 kg P ha-1 ano-1. Nas pastagens em monocultura, os aumentos na taxa de lota??o de 2 para 3 animais ha-1 e de 3 para 4 animais ha-1 causaram decr?scimos na reciclagem de P na liteira de respectivamente, 11 e 6%.Provavelmente essas altas taxas de lota??o provocam um decl?nio das pastagens devido ? menor adi??o de P ao sistema solo. A presen?a da leguminosa nas pastagens provocou um aumento significativo na reciclagem de P pela deposi??o da liteira variando de 12,5 a 14,3 kg P ha-1 ano-1 e 25,0 a 37,6 kg K ha-1 ano-1.

Submitted by Verena Bastos (verena@uefs.br) on 2015-07-28T14:31:48Z No. of bitstreams: 1 Disserta??o Simone Dias Fundo de Pasto 1970-2007.pdf: 2145133 bytes, checksum: 1b8f51850de7c31fda88d35f61c8d22c (MD5) / Made available in DSpace on 2015-07-28T14:31:48Z (GMT). No. of bitstreams: 1 Disserta??o Simone Dias Fundo de Pasto 1970-2007.pdf: 2145133 bytes, checksum: 1b8f51850de7c31fda88d35f61c8d22c (MD5) Previous issue date: 2014-08-28 / The fund is a community pasture form of land use, especially for extensive grazing of animals, practiced primarily in northeastern Bahia. Its origin is related to the occupation of the hinterland for extensive cattle and their problems with regard to the security of land tenure, dating back to the Land Act 1850 and subsequent legislation that does not bolster its form of land use. This paper discusses the way of life of the bottom of the pasture Lagedas Aroeiras, municipality of Uau? community - BA, through community grazing, labor relations and sociability in the community and how the actions of the state with the implementation of policies developmental regionalizantes during the military dictatorship, contributed to the process of commodification of their lands, emphasizing the resistance to this commercialization through community organization and partnership and joint the community down to ensure that their way of living and create still exist. Community land use also constitutes as an instrument of resistance to the capitalist system that emphasizes individuality and, above all, private property as production and economic development strategy. But the regularization of their land, so that resistance to capitalism can continue to exist is necessary because without this, the continuity of the fund is threatened pasture. / O fundo de pasto ? uma forma comunit?ria de utilizar a terra, sobretudo para o pastoreio extensivo de animais, praticada principalmente na Regi?o Nordeste da Bahia. Sua origem est? relacionada ? ocupa??o do sert?o para cria??o extensiva de gado e os seus problemas com rela??o ? garantia da posse da terra, remontam a Lei de Terras de 1850 e legisla??es posteriores que n?o amparam a sua forma de utiliza??o da terra. O presente trabalho discute o modo de vida da comunidade de fundo de pasto Lage das Aroeiras, munic?pio de Uau? ? BA, atrav?s do pastoreio comunit?rio,das rela??es de trabalho e das sociabilidades presentes na comunidadee como as a??es do estado com a implanta??o das pol?ticas desenvolvimentistas regionalizantes durante a ditadura militar, contribu?ram para o processo de mercantiliza??o de suas terras, enfatizando a resist?ncia a essa mercantiliza??o atrav?sda organiza??o comunit?ria e das parcerias e articula??es que a comunidade estabelece para garantir que seu modo de viver e criar continue existindo. A utiliza??o comunit?ria da terra se constitui tamb?m como um instrumento de resist?ncia ao sistema capitalista que privilegia a individualidade e, sobretudo, a propriedade privada como estrat?gia de produ??o e desenvolvimento econ?mico. Mas, para que essa resist?ncia ao capitalismo possa continuar a existir, ? necess?ria a regulariza??o jur?dica de suas terras, pois sem esta, a continuidade do fundo de pasto est? amea?ada.

A 2-year grazing study was conducted to evaluate the growth performance, ruminal fermentation, carcass characteristics, and fatty acid compositions in subcutaneous adipose tissue of beef steers grazing tall fescue (Festuca arundinacea Shreb.; TF) pastures without or with N fertilization. Nitrogen fertilization increased crude protein concentration of TF pasture and average daily gain of beef steers. Increase in total volatile fatty acids (VFA) and ammonia-N (NH3-N) concentrations were detected in steers grazing fertilized TF. In comparison with steers on feedlot, pasture-finished steers had greater proportions of cis-9, trans-11 CLA and C18:3 n-3, but lower n-6:n-3 ratio in adipose tissue. In the first in vitro study using 2 energy supplements [corn or dried distillers grains with solubles (DDGS)] and 4 pasture mixture forages [TF without or with N fertilizer (TF˗NF or TF+NF), TF-alfalfa mixture (TF+AF), and TF-birdsfoot trefoil mixture (TF+BT)], we found that corn supplementation increased total VFA and propionate concentrations, while DDGS supplementation decreased total VFA concentrations. Lower NH3-N concentration and methane (CH4) production were observed due to energy supplementation, in particular when corn grain was supplemented. Similar NH3-N:VFA ratios were detected in the cultures fed the TF+NF and the TF+BT. This result indicates that the TF+BT had similar fermentation efficiency on in vitro ruminal metabolism compared with the TF+NF. The second in vitro study was performed to investigate the effects of grass-to-legume ratios of 3 different TF-legume mixed diets on in vitro fermentation characteristics in continuous cultures. Propionate concentration increased with the increasing of legume proportion in the mixed diets. The greatest propionate concentration was shown by cultures fed the TF+CM, while the TF+AF and the TF+BT maintained a similar propionate concentration. Increasing legume proportion in the forage diets also increased NH3-N concentration, but decreased CH4 production in the cultures. Further decrease of CH4 production was recorded when the TF+BT was fed to the cultures. Overall results from the grazing study demonstrate that N fertilizer can improve nutrient quality of TF as well as growth performance of grazing steers, while the in vitro studies showed positive effects of grass-legume mixture diets on in vitro microbial metabolism by improving ruminal fermentation and reducing CH4 production.

The use of pasture to provide low cost feed for dairy and other farm animals is an important factor in the success of livestock operations. Some of the factors which influence the income from pasture land are: management, pasture mix, and climate. The management of a pasture can determine to a great extent the value of pasture in a farming enterprise. Irrigating the pasture at the right time, using the right fertilizer, and proper methods of harvesting are examples of some of the management problems facing the grassland farmer.

Although New Zealand is fortunate in having a climate mild enough to allow some growth of pasture in winter even in the extreme south of the South Island (Duffy, 1971), growth is nevertheless considerably less than in spring and summer. O’Connor et al, (1968) point out that at Lincoln, Canterbury, winter production from a New Zealand Certified Grasslands Ruanui Perennial ryegrass (Lolium perenne c.v.) and New Zealand Certified Grasslands Huia white clover (Trifolium repens c.v.) sward is at best only 8% of the mean total annual dry matter (D.M.) production. A similar seasonal pattern is shown by irrigated pastures (Rickard, 1968), as well as pastures in the milder North Island of New Zealand (O’Connor and Vartha, pers comm.). Stocking of grazing animals is normally related to the growth rate of pastures in the spring, with conserved hay or silage, plus specially grown greenfeed or root crops being fed if necessary to offset the winter feed deficit. However on hill country too steep for tractor cultivation, cropping and conservation are not possible. Animals have to rely upon in situ grazing of native or dominant browntop (Agrostis tenuis) swards which may not have been improved by the aerial introduction of clovers. In an unimproved state, the quality and quantity of the herbage grown on such areas are low, Molloy (1966) have discussed clover introduction into native swards and the notably beneficial result this has on stock thrift, particularly during the winter period. Considerably better growth rates of stock grazing legumes rather than grasses have been noted by many authors including Ulyatt, (1971), and McLean et al (1962); this superiority being due largely to the greater digestible organic matter intake and higher ratio of soluble to insoluble carbohydrate associated with the herbage of legumes (Ulyatt, 1971). Consequently the presence of clover, and the winter activity of this, have an important influence on the productivity of steep hill country during winter. An increase of winter activity is also desirable, but not essential, in clover associated with flat or gently rolling pastures. The main pasture legume used in New Zealand has, in the past, been the white clover cultivar Huia. Whilst since 1945 selection and breeding of ryegrasses has brought about a very considerable improvement in the winter or cool season activity of these (Corkill, 1966), no legume cultivar having an increased level of cool-season activity has been released to commerce in New Zealand over the same period to date. Breeding for increased winter growth has been an objective of the Grasslands Division Plant Breeding Section for many years (Barclay, 1960). Since 1957, breeding and selection work has been proceeding with the objective of increasing the winter growth of the New Zealand Certified Grasslands white clover cultivar – Huia (henceforth to be referred to as Huia) without sacrificing the moderately good summer growth of this strain, (Barclay, 1969). Seed of a promising cultivar selected during the course of this work – New Zealand Grasslands 4700 white clover, (henceforth to be referred to as 4700) became available for testing in 1967. The investigation to be reported here aimed to measure the cool-season activity of 4700 by comparison with that of Huia, at the same time elucidating if possible the factors controlling this growth.

<p>Natural forest dynamics is a foundational topic of forest science. A new Wood Pasture hypothesis considering large herbivore as driving force in forest ecosystem is now challenging the traditional High Forest hypothesis, in which vegetation is regarded as main driving force. In this study, a model-based approach is applied to investigate differences between these two hypotheses and the determine factors in the system. A theoretical landscape of 1 km²formed by 100*100 cells is set up with 100 vegetation patches and free moving herbivores on. Our null hypothesis that herbivores make no difference in vegetation dynamics especially at canopy level is rejected. It is found that synchronization of herbivore behaviors is the most influencing factor of how a landscape might be shaped. It is also found that landscape could be a mosaic of both high forest and wood pasture depends on large herbivore’s herd size.</p>