Página 1 dos resultados de 7179 itens digitais encontrados em 0.026 segundos

Use of blanks to determine in vitro net gas and methane production when using rumen fermentation modifiers

ARAUJO, R. C.; PIRES, A. V.; MOURAO, G. B.; ABDALLA, A. L.; SALLAM, S. M. A.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
56.12%
Blanks (flasks without substrate containing only inoculum and medium) are used in vitro to correct for gas. CH(4) and residual organic matter (OM) fermented in inoculum. However inclusion of rumen fermentation modifiers may affect fermentation of OM in the substrate and inoculum. Thus, data correction using blanks that lack additives may result in inaccurate adjustment for background fermentation. Our objective was to evaluate impacts of using blanks containing additive (i.e., specific blanks) or blanks without additive on estimation of in vitro net gas and CH(4) production. We used the semi-automatic in vitro gas production technique including monensin sodium at 2.08 mg/l of buffered rumen fluid (Experiment 1) or carvacrol, eugenol and 1,8-cineol at 667 mg/l (Experiment 2) in flasks with substrate and in blank flasks. At 16h of incubation, monensin reduced (P <= 0.02) total gas production in flasks containing substrate (162.0 ml versus 146.3 ml) and in blanks (84.4 ml versus 79.2 ml). Total methane production was also decreased (P <= 0.05) by adding monensin to flasks containing substrate (15.7 ml versus 11.9 ml) as well as in blanks (6.4 ml versus 5.0 ml). Inclusion of carvacrol or eugenol reduced (P <= 0.05) total gas and CH(4) production in flasks with substrate and in blanks...

Teores de taninos e produção de gases in vitro da silagem de sorgo com adição de níveis crescentes de guandu; Tannins Levels and gas production in vitro of sorghum silage with the addition of increasing levels of pigeon pea

Pinedo, Lerner Arévalo
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 30/11/2009 PT
Relevância na Pesquisa
66.02%
Na alimentação animal, o sorgo pode ser explorado de diversas formas. Além dos grãos, a planta pode ser oferecida na forma de silagem, rolão, verde ou ainda pastejada; embora o valor nutritivo pode sofrer algumas variações pela presença ou ausência de compostos fenólicos como os taninos condensados. O objetivo deste trabalho foi avaliar a composição química-bromatológica, qualidade fermentativa e produção de gases in vitro nas silagens de sorgo granífero adicionados com diferentes níveis de guandu. O estudo foi dividido em dois experimentos. O primeiro estudo (Capítulo 3) avaliou os efeitos da adição de forragem de guandu sobre a composição química-bromatológica e fermentativas da silagem de sorgo granífero. Os tratamentos foram compostos por: T1 - Silagem com 100% de sorgo, T2 - Silagem com 25% de guandu e 75% de sorgo, T3 - Silagem com 50% de guandu e 50% de sorgo, T4 - Silagem com 75% de guandu e 25% de sorgo e T5 Silagem com 100% de guandu. As variáveis estudadas para a composição química e fermentativas das silagens foram: matéria seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente neutro (FDA), carboidratos totais (CHOT), matéria mineral (MM), fenóis totais (FT)...

Desenvolvimento ponderal, características da carcaça e eficiência da nutrição energética e protéica no metabolismo ruminal de búfalos e produção de gases in vitro; Growth rate, carcass characteristics and efficiency of nutritional energy and protein metabolism in rumen of buffalo and gas production in vitro

Alves, Teresa Cristina
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 01/07/2010 PT
Relevância na Pesquisa
65.98%
Com o objetivo de estudar a espécie bubalina quanto ao desempenho de machos bubalinos do nascimento ao abate em regime de pastejo e as características de carcaça em dois pesos de abate, assim como o metabolismo ruminal de dietas com diferentes níveis de proteína e energia e a produção de gases in vitro, o presente trabalho apresenta-se avaliações feitas em quatro partes. A parte 1 foi realizada com búfalos em crescimento criados à pasto, do nascimento até atingirem dois pesos distintos de abate (517 e 568 kg). Avaliações do desempenho foram realizadas com medição do peso vivo, perímetro torácico, altura de cernelha e comprimento corporal e as avaliações das características da carcaça e carne com determinação do rendimento de carcaça quente e fria, perda no resfriamento, peso da gordura, peso do fígado, temperatura e pH da carcaça, área de olho de lombo, espessura de gordura subcutânea, marmorização, maciez e coloração. A segunda parte avaliou dietas com três níveis de proteína (9%, 12% e 15%) no metabolismo ruminal. Os Itens analisados foram: consumo de nutrientes, pH, amônia e ácidos graxos voláteis no rúmen e degradabilidade in situ. Na parte 3, foram avaliadas dietas com dois níveis de proteína (9 e 15%) e dois de energia (65 e 69% NDT) no metabolismo ruminal. Além dos Itens avaliados na parte 2 foram ainda analisados a digestibilidade com uso de marcador...

Uso de inóculo de fezes como substituição do conteúdo ruminal de bubalinos na técnica in vitro de produção de gases; Use of faeces as inoculum as alternative for buffalo rumen contents in the in vitro gas production technique

Simões, Nancy Rodrigues
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 17/02/2012 PT
Relevância na Pesquisa
65.98%
Com o objetivo de estudar o uso de inóculo de fezes em substituição do conteúdo ruminal de bubalinos na técnica in vitro de produção de gases, este presente trabalho comparou as avaliações realizadas em três ensaios. Foram utilizados três bubalinos da raça Mediterrâneo, machos, adultos, castrados, fistulados no rúmen com média de peso vivo de 450 (± 18,7) kg. Estes animais receberam uma dieta basal, composta de silagem de milho (70%) e concentrado (30%). Estes animais foram os doadores dos 2 tipos de inóculos, que foram conteúdo ruminal (CR) e fezes. O primeiro ensaio realizado foi com alimentos concentrados: grão de milho, farelo de soja, farelo de trigo e farelo de algodão; o segundo ensaio foi com leguminosas forrageiras: alfafa (Medicago sativa L. ), estilosantes pioneiro (Stylosanthes macrocephala cv. Pioneiro), soja perene (Neonotonia wightii) e leucena (Leucaena leucocephala); e o terceiro e último ensaio foi realizado com gramíneas forrageiras: capim braquiarão (Brachiaria brizantha cv. Marandu), capim buffel (Cenchrus ciliaris L. cv. Biloela), estrela africana (Cynodon plectostachyus) e capim mombaça (Panicum maximum Jacq. cv. Mombaça). Os valores médios obtidos de produção potencial de gases em cada ensaio foram menores (P<0...

Metodologia para aplicação de fontes renováveis de energia elétrica em plataformas marítimas de produção de petróleo e gás natural.; Application methodology for renewable sources of electricity at offshore petroleum and gas production platforms.

Oliveira, Maurício Figueiredo de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 22/02/2013 PT
Relevância na Pesquisa
56.06%
A utilização de fontes renováveis em plataformas de produção de petróleo e gás natural atualmente é baseada em aplicações experimentais e esparsas. Contudo, a aplicação dessas fontes de forma estruturada permite aumentar a confiabilidade de sistemas críticos e diminuir a emissão de poluentes. Com foco nos projetos para desenvolvimento de produção dos campos petrolíferos do pré-sal no Brasil, esse trabalho apresenta uma proposta de metodologia para avaliação de utilização de fontes renováveis de energia elétrica em plataformas marítimas de produção de petróleo e gás natural. Para isso, foi desenvolvido um fluxograma de projeto e uma metodologia multicritério. O fluxograma de projeto determina as etapas e atividades requeridas para uma adequada aplicação da metodologia de avaliação. Enquanto a metodologia multicritério busca captar os valores e percepções de projetistas, operadores e mantenedores a respeito de características dos dispositivos conversores de energia renovável. A metodologia proposta é aplicada em um caso de plataforma tipo fixa e em outro caso de plataforma tipo FPSO. Esse segundo caso representa características físicas das embarcações utilizadas para desenvolvimento da produção na camada pré-sal...

Avaliação do sistema de monitoramento computadorizado de digestão in vitro: 3. Desaparecimento da matéria seca e/ou FDN pela produção de gás

Campos, Fábio Prudêncio de; Bose, Max Lázaro Vieira; Boin, Celso; Lanna, Dante Pazzanese Duarte; Morais, Jozivaldo Prudêncio Gomes de
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: 537-544
POR
Relevância na Pesquisa
56.09%
RESUMO - Os objetivos deste trabalho foram avaliar o sistema de monitoramento computadorizado da produção de gás in vitro e compará-lo com os métodos in vivo e in situ. Nos métodos de digestibilidade (MS), foram utilizadas amostras de silagens de milho com alto/baixo teor de MS, com/sem inoculante. Avaliando a digestibilidade das silagens, pelo gás produzido na fermentação, os resultados da extensão da degradação (A+D) foram: 21,5; 22,6; 22,1; e 20,9 mL de gás/100 mg MS, sem diferença significativa. Os coeficientes de determinação obtidos na produção de gás total, em relação ao potencial de degradação obtido in situ, mostraram-se elevados para silagem de milho com alta MS inoculada (R²= 0,99), alta MS não-inoculada (R²= 0,98), baixa MS inoculada (R²= 0,94) e baixa MS não-inoculada (R²=0,93). O desaparecimento da MS e/ou fibra em detergente neutro (FDN), quantificada pelo gás produzido no sistema in vitro/gás, apresentou resultados semelhantes aos demais métodos avaliados.; Resumo - The objective of this work was to evaluate the computerised monitoring of the in vitro gas production system and to compare with in vivo and in situ methods. In the degradation methods, corn silage samples with high/low dry matter (DM) contents...

Effects of Condensed Tannins from Quebracho Extract on the Kinetic of in vitro Gas Production on Trifolium repens, Lotus corniculatus and Lolium perenne

Vieira, Sandrine C.; Borba, Alfredo Emílio Silveira de
Fonte: David Publishing Company Publicador: David Publishing Company
Tipo: Artigo de Revista Científica
Publicado em /11/2011 ENG
Relevância na Pesquisa
66.01%
The aim of this work was to study the effect of condensed tannins (CT) on the kinetic of gas production in vitro, on the three main species of Azorean pasture: Trifolium repens, Lotus corniculatus and Lolium perenne, using Quebracho extract as the source of CT, and also to calculate total tannins and condensed tannins on the species studied. Lotus corniculatus, Lolium perenne and Trifolium repens were tested in vitro with the inclusion of Quebracho extract in doses of 0%, 2.5% and 5% DM. The total content in tannins was determined in the 3 species. We have found, in comparison with standard tannic acid, that tannins exist in the flower of T. repens (0.81 equivalents of tannic acid) and in L .corniculatus (1.07 equivalents of tannic acid) but not in L .perenne (0 equivalents of tannic acid). The concentration of condensed tannins in the 3 species was: 0.34 mg/mL for T. repens; 0.83 mg/mL for L. corniculatus and 0 mg/ml for L. perenne. We verified that a significant reduction (P < 0.05) of gas production happened for doses of 5% of CT in comparison with the other two concentrations: 0% and 2.5% of CT. The results of this study express a reduction of the fermentation rate, which implies a reduction of gas production, so, a reduction of methane emission to the atmosphere and an increase of exploitation of the protein by ruminants.

Methane production of two roughage and total mixed ration as influenced by cellulase and xylanase enzyme addition

Gemeda,Belete Shenkute; Hassen,Abubeker
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2015 EN
Relevância na Pesquisa
56.06%
In recent decades supplementation of animal feeds with exogenous fibrolytic enzymes has substantially improved digestibility and animal performance. However, information related to associated methane production is limited and inconsistent. This study evaluated the effect of cellulase and xylanase enzymes on in vitro methane production of Eragrostis curvula hay, maize (Zea mays) stover and a total mixed ration (TMR) at seven levels of the two enzymes. Feed samples were incubated for 2, 12, 24 and 48 h in an in vitro batch culture with buffer and rumen fluid, and fibrolytic enzymes. Gas production was measured using a pressure transducer connected to a data tracker, while methane gas was analysed using a gas chromatograph which was calibrated with standard CH4 and CO2. Increases in the level of enzyme application resulted in increases in gas volume, total volatile fatty acid (VFA) production, dry matter (DM) disappearance and associated increases in methane production. The linear increase in percentage and volume of methane production in tandem with increases in level of enzyme application might be due to increased fermentation, and organic matter degradability that resulted in a shift in VFA production towards acetate. Considering the efficiency of DM and neutral detergent fiber degradation and production of associated VFA with levels of enzymes...

Influence of Yeast Fermented Cassava Chip Protein (YEFECAP) and Roughage to Concentrate Ratio on Ruminal Fermentation and Microorganisms Using In vitro Gas Production Technique

Polyorach, S.; Wanapat, M.; Cherdthong, A.
Fonte: Asian-Australasian Association of Animal Production Societies (AAAP) and Korean Society of Animal Science and Technology (KSAST) Publicador: Asian-Australasian Association of Animal Production Societies (AAAP) and Korean Society of Animal Science and Technology (KSAST)
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
56.09%
The objective of this study was to determine the effects of protein sources and roughage (R) to concentrate (C) ratio on in vitro fermentation parameters using a gas production technique. The experimental design was a 2×5 factorial arrangement in a completely randomized design (CRD). Factor A was 2 levels of protein sources yeast fermented cassava chip protein (YEFECAP) and soybean meal (SBM) and factor B was 5 levels of roughage to concentrate (R:C) ratio at 80:20, 60:40, 40:60, 20:80, and 0:100, respectively. Rice straw was used as a roughage source. It was found that gas production from the insoluble fraction (b) of YEFECAP supplemented group was significantly higher (p<0.05) than those in SBM supplemented group. Moreover, the intercept value (a), gas production from the insoluble fraction (b), gas production rate constants for the insoluble fraction (c), potential extent of gas production (a+b) and cumulative gas production at 96 h were influenced (p<0.01) by R:C ratio. In addition, protein source had no effect (p>0.05) on ether in vitro digestibility of dry matter (IVDMD) and organic (IVOMD) while R:C ratio affected the IVDMD and IVOMD (p<0.01). Moreover, YEFECAP supplanted group showed a significantly increased (p<0.05) total VFA and C3 while C2...

The New Albany Shale gas play in southern Indiana

Comer, J. B.; Hasenmueller, N. R.; Mastalerz, M. D.; Rupp, J. A.; Shaffer, N. R; Zuppann, C. W
Fonte: Universidade de Indiana Publicador: Universidade de Indiana
Tipo: Conferência ou Objeto de Conferência Formato: 30458158 bytes; application/pdf
EN_US
Relevância na Pesquisa
56.09%
This poster was presented at the 2006 Eastern Section American Association of Petroleum Geologists, 35th Annual Meeting, in Buffalo, N.Y., October 8-11, 2006.; The New Albany Shale (Devonian and Mississippian) in Indiana is mostly brownish-black organic-rich shale with lesser greenish-gray shale. The formation is 100 to 140 feet thick in southeastern Indiana and dips and thickens to the southwest into the Illinois Basin, where it attains a thickness of more than 360 feet in Posey County. Gas production from New Albany Shale began in 1885 and drilling activity continued into the 1930s, when interest waned in favor of more lucrative opportunities elsewhere. Renewed activity, driven by higher gas prices, has been brisk since the mid-1990s, witnessed by the completion of more than 400 productive wells. The majority of these wells were drilled in Harrison County, where production typically occurs at depths from 500 to 1,100 feet and production rates generally range from 20 to 450 MCFGPD. In the past 2 years, Daviess County and surrounding areas have become the focus of New Albany exploration after the El Paso Production No. 2-10 Peterson horizontal discovery well was rumored to have tested 1.3 MMCFGPD at an approximate measured depth of 2...

Harnessing African Natural Gas : A New Opportunity for Africa's Energy Agenda?

Santley, David; Schlotterer, Robert; Eberhard, Anton
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
56.14%
Sub-Saharan Africa's persistent power shortages act as a severe constraint on its economic and human development. Over the last several years, a series of major offshore gas discoveries in Mozambique and Tanzania have rekindled interest in expanding the use of natural gas to address the continent's power shortages. Once thought of as a Nigeria-only story, gas-to power in Sub-Saharan Africa is now being considered in a continent-wide context, both as a supplement to Africa's abundant hydropower resources and as a replacement for more carbon intensive coal and liquid fuels. But the concentration of gas resources in just a few countries and the virtual absence of gas transportation infrastructure create economic challenges to the wider adoption of gas as a power generation fuel, particularly in smaller countries that cannot achieve economies of scale in gas production and transportation. As a result, the timeline between the discovery of gas and its commercialization is often measured in decades. This study examines the economic conditions facing policy makers...

Regional Gas Trade Projects in Arab Countries, Volumes 1 and 2

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Mining/Oil and Gas; Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
56.18%
Arab countries hold about 29 percent of the world's proven gas reserves, but every country (except Qatar and Algeria) is short of the gas supply needed to meet its current and projected demand. The rapid growth in gas demand is mostly a consequence of a sharp increase in electricity consumption. Gas trade in the Arab world has been dominated by the objective of exporting gas in the form of liquefied natural gas (LNG) to points in Asia, Europe, and North America. Gas trade within the region is limited to rather small volumes, moved from Algeria to Tunisia and Morocco; from Egypt to Jordan, Syria, and Lebanon; and from Qatar to the United Arab Emirates (UAE) - all through pipelines. The shortage of gas in the Arab countries has become more pronounced, justifying the higher gas prices needed to secure imported gas or to encourage domestic gas production. Such changes in the landscape provide an impetus for the Arab world to optimize the region's gas resources, at least partly on the basis of meeting growing regional demand. The objective of this study is to assist the attempt by: (i) identifying the opportunities for gas trade through cross-border gas pipelines and LNG; (ii) assessing the economic and political aspects of the identified projects; (iii) presenting financing and implementation schemes that utilize the synergy between the public and private sector in project formulation and development; and (iv) reviewing the legal...

Gas Dynamics during Bench-Scale Electrical Resistance Heating of Water, TCE and Dissolved CO2

Hegele, Paul
Fonte: Quens University Publicador: Quens University
Tipo: Tese de Doutorado
EN; EN
Relevância na Pesquisa
56.08%
In situ thermal treatment (ISTT) applications require successful gas capture for the effective remediation of chlorinated solvent dense non-aqueous phase liquid (DNAPL) source zones. Gas production and transport mechanisms during bench-scale electrical resistance heating (ERH) experiments were examined in this study using a quantitative light transmission visualization method. Processed images during water boiling indicated that gas bubble nucleation, growth and coalescence into a connected steam phase occurred at critical gas saturations of Sgc = 0.233 ± 0.017, which allowed for continuous gas transport out of the heated zone. Critical gas saturations were lower than air-water emergence gas saturations of Sgm = 0.285 ± 0.025, derived from the inflection point of ambient temperature capillary pressure-saturation curves. Coupled electrical current and temperature measurements were identified as a metric to assess gas phase development. Processed images during co-boiling of pooled trichloroethene (TCE) DNAPL and water indicated that discontinuous gas transport occurred above the DNAPL pool. When colder zones were introduced, condensation prevented the development of continuous steam channels and caused redistribution of DNAPL along the vapour front. These results suggest that water boiling temperatures should be targeted throughout the subsurface (i.e....

Comparison of equine caecal and faecal inoculums for estimating the nutritive value of concentrate feeds using the gas production technique

Cabo, Ângelo Daniel Santos do
Fonte: Universidade de Trás-os-Montes e Alto Douro Publicador: Universidade de Trás-os-Montes e Alto Douro
Tipo: Dissertação de Mestrado
ENG
Relevância na Pesquisa
56.09%
Dissertação de Mestrado em Engenharia Zootécnica; Este trabalho teve por objetivo comparar a atividade fermentativa de inóculo cecal e fecal de equino utilizando a técnica da produção de gás. Para este efeito, foram utilizados dois equinos castrados canulados no ceco, alimentados ao nível da manutenção com um feno de prado natural (80%) e alimento composto (20%), sendo distribuída metade da quantidade diária às 08:00 h e a restante às 20:00 h, para se evitar seleção e desperdício de alimento. Foram estudados 2 alimentos (milho e cevada). As amostras de conteúdo cecal e de fezes foram recolhidas 2h após a refeição matinal para recipientes previamente aquecidos e saturados com CO2. O conteúdo cecal foi filtrado através de 8 camadas de gaze e misturado com solução nutritiva tampão (SNT). As amostras fezes foram misturadas e incubadas durante 1h com SNT antes da incubação. As amostras de alimento foram incubadas com 60 ml de inóculo cecal ou fecal, em duplicado e repetidos 3 vezes no tempo para cada tipo de inóculo. Após 96h de fermentação, foi avaliado o pH, o azoto amoniacal (NH3-N), os ácidos gordos voláteis (AGV) totais e a produção de gás. A análise de dados foi realizada através de uma análise de variância (ANOVA) considerando o alimento e o tipo de inóculo como fontes de variação. Foram observadas diferenças entre alimentos ao nível do pH (p<0.05)...

Effect of preservation on fermentative activity of rumen fluid inoculum for in vitro gas production techniques

Hervás, Gonzalo; Frutos, Pilar; Giráldez, Francisco Javier; Mora Martínez, Manuel José; Fernández, Begoña; Mantecón, Ángel R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 94510 bytes; application/pdf
ENG
Relevância na Pesquisa
66.01%
12 pages, 5 tables.-- Available online Jun 6, 2005.; Use of preserved rumen fluid (RF) as microbial inoculum for in vitro gas production techniques (IVGPT) would be of practical importance when access to ruminally cannulated animals is limited. This experiment was designed to study effects of RF preservation on its subsequent fermentative activity. Four substrates being: alfalfa hay (AH), barley straw NDF (BS-NDF), cellulose and starch were incubated with rumen inoculum obtained from 12 rumen cannulated grazing sheep, of which six (G) received no supplement and the other 6 (G+S) received 500 g/day of a concentrate. Sub-samples of RF were processed without delay (i.e., control) or stored at approximately 0°C in a chest with crushed ice for 3, 6 and 24 h (treatments 3, 6 and 24 h, respectively) or at −18 °C for 24 h in a freezer (treatment 24 F). An IVGPT was used to determine the rate and extent of gas production and DM disappearance. Average fermentation rate (AFR) and extent of degradation in the rumen (ED) were estimated. Incubations with inoculum derived from supplemented sheep (G+S) resulted in faster rates of gas production (with differences, as proportionate increases, of 0.77 for the barley straw NDF; P < 0.01), lower lag times (e.g....

Avaliação das silagens de girassol (hibrido m734) obtidas em diferentes épocas de ensilagem pela técnica in vitro semi-automática de produção de gases; Evaluation of silages from hybrid m734 of sunflower obteined in diferent cutting times using the semi-automated "in vitro" gas production technique

Pereira, Luiz Gustavo Ribeiro; Maurício, Rogério Martins; Gonçalves, Lúcio Carlos; Tomich, Thierry Ribeiro; Rodrigues, José Avelino Santos; Rodriguez, Norberto Mario
Fonte: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia Publicador: Universidade de São Paulo. Faculdade de Medicina Veterinária e Zootecnia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; ; ; ; ; Formato: application/pdf
Publicado em 01/01/2005 POR
Relevância na Pesquisa
66.05%
Para que o girassol possa ser utilizado com sucesso na forma de silagem, é necessário que se determine o ponto ideal de ensilagem. O objetivo desse experimento foi avaliar através da técnica in vitro semi-automática de produção de gases a cinética de degradação da matéria orgânica (MO) e matéria seca (MS) das silagens do híbrido M734 ensilado com 100, 107, 114 e 121 dias após o plantio. As leituras de pressão dos gases foram feitas através de um transdutor de pressão às 2, 4, 6, 8, 10, 12, 15, 19, 24, 30, 36, 48, 72, 96 h pós-inoculação. A cinética ruminal foi descrita matematicamente por meio dos parâmetros: potencial máximo de produção de gases, "lag time", taxa de produção de gases (m) e degradabilidade efetiva da MO e MS para diferentes taxas de passagem (2, 5 e 8%/h) por um modelo unicompartimental. Verificou-se que o corte da cultura em estádios mais tardios levaram a redução no potencial máximo de produção de gases para a MO (162, 155, 144 e 139 mL) e MS (138, 129, 121 e 119 mL); elevação da "lag time" para MO (2,4, 2,5, 2,8 e 2,9 h) e MS (2,5, 2,5, 3,0 e 3,0 h); e diminuição do m para a MO (0,023, 0,022, 0,017 e 0,017 mL/h) e MS (0,022, 0,020, 0,015 e 0,016 mL/h) para as épocas 100, 107...

Evaluating the Potential for Offshore Oil and Gas Production in North Carolina

Moore, Kathleen
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project Formato: 700115 bytes; application/pdf
EN_US
Relevância na Pesquisa
65.95%
Recurring energy and economic crises promote legislation and government action focused on the development of domestic energy sources to alleviate foreign dependency and create jobs for a rising percentage of unemployed Americans. Within the past year regulatory changes produced the potential for oil and gas production along the outer continental shelf of North Carolina. Exploring the history of development and recognizing existing mandates aid in understanding the full range of issues involved in the offshore leasing and production process. Examining the six steps of a complete production cycle allows for the outline of activities to provide a clear timeline for the risk of various impacts. Development procedures along the North Carolina outer continental shelf could significantly alter the economic and environmental conditions of coastal communities. Potential impacts are not limited to benefits for the economy and risks for the environment but include trade-offs within each sector. In striving for effective and successful management of offshore resources, emphasis should be placed on finding a balance between growth and stability. Future research action should emphasize environmental risks and feasibility analysis with a focus on understanding socioeconomic aspects of development. This compilation of necessary information will provide interested stakeholders an available framework for evaluating offshore energy projects using a policy for endorsing responsible and appropriate responses to a national call for offshore oil production. Although development seems to promise economic and energy dependence relief...

Inclusion of field pea hay (Pisum sativum L.) and in vitro gas production in diets for growing lambs

González García,Ulises Alejandro; González Ronquillo,Manuel; Estrada Flores,Julieta G.; Bastida García,Jorge Luis; Pecador Salas,Nazario; Salem,Abdel-Fattah Z.M.
Fonte: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria Publicador: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 EN
Relevância na Pesquisa
66.04%
The use of byproducts such as field pea {Pisum sativum) is an alternative to feed sheep, the objective of this study was to evaluate the intake and digestibility in sheep fed different levels of field pea hay (FPH). Twenty Rambouillet lambs (with an initial BW of 26.0 ± 0.43 kg) were fed to one of four treatments of 5 animals of each (0%, 25%, 50% and 75% inclusion of PH as dry matter basis). The content of CP for the FPH was 8%. There were no significant differences (P>0.1) between treatments for DM intake (947.6 ± 32.3 g/d), OM (856.7 ± 24.8) and NDF (583.5 ± 30.6), as well as digestibility (g/lOOg) of DM (50.3 ± 1.0), OM (49.4 ± 2.38) and NDF (57.0 ± 2.23). N intake was lower (P<0.05) for PH 25% compared to 0%, no significant differences (P>0.1) for N excretion in feces, urine and N balance between treatments. In vitro gas production in the fraction A (ml gas / g DM incubated) was lower in FPH compared to corn stover (CS) and corn grain (CG). Fraction b was higher (P <0.05) for FPH compared to the other ingredients, however there were no differences (P>0.1) between CS and CG for fraction c. Gas production (ml gas / g DM disappeared) was lower in FPH compared to CS and CG. In vitro DM disappearance was lower for FPH with respect to CG...

Chemical composition and in vitro gas production of some legume browse species in subtropical areas of Mexico

Garcia-Montes de Oca,C. A.; Gonzalez-Ronquillo,M.; Salem,A. Z. M.; Romero-Bernal,J.; Pedraza,J. F.; Estrada,J. G
Fonte: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria Publicador: Universidad Autónoma de Yucatán, Facultad de Medicina Veterinaria
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2011 EN
Relevância na Pesquisa
66.02%
The objective of the present study was to determine the chemical composition and in vitro gas production of different legume and wild arboreal pods. Seven seeds of legume browse species, Mexican calabash (Crescentia alata), esculent leadtree (Leucaena esculenta), guamuchil (Phitecellobium dulce), bastard cedar (Guazuma ulmifolia), needle bush (Acacia farnesiana), mimosa (Mimosa sp.) and elephant ear tree (Enterolobium cyclocarpum). Were evaluated for their chemical composition (g/kg DM) and in vitro gas production pattern. Crude Protein was higher for L. esculenta (220) and lower for G. ulmifolia (70). Neutral and acid detergent fiber were higher for G. ulmifolia (687 and 554) and lower for A. farnesiana (267 and 176). Lignin was higher for Mimosa sp. (219) and lower for P. dulce (81). Total gas production (ml gas/g DM) of P. dulce (187) and E. cyclocarpum (164) were higher (P<0.001) than Mimosa sp. The lowest values were for C. alata (108), G. ulmifolia (102), L. esculenta (99) and A. farnesiana (90). The nutritional characteristics of L. esculenta and A. farnesiana might be used as supplements in ruminant diets, due to their major content in CP and in vitro digestibility, representing an alternative protein supplement during dry season.

Effect of pesticides applied in cowpea production on rumen microbial fermentation of cowpea haulms as reflected in in vitro gas production

Antwi,C; Osafo,E.L.K; Fisher,D.S; Yacout,H.M; Donkoh,A; Hassan,A.A; Sobhy,S.M.M; Adu-Dapaah,H; Salem,A.Z.M
Fonte: South African Journal of Animal Science Publicador: South African Journal of Animal Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2014 EN
Relevância na Pesquisa
66.07%
The present study assessed the effect of lambda cyhalothrin, cypermethrin and dimethoate residues in cowpea haulm on microbial fermentation using gas syringes as incubators. The lambda cyhalothrin, cypermethrin and dimethoate were applied at the vegetative, flowering and podding stages of the cowpea at the rate of 2.66 mg/L, 5.14 mg/L and 6.68 mg/L of water, respectively. Dimethoate was detected in the cowpea haulm at the highest concentration of 1.38 mg/kg. The haulm with no pesticide treatment was incubated with media containing rumen fluid, and pesticides were added at concentrations of 40 mg/kg, 80 mg/kg and 120 mg/kg. In vitro gas production was measured at 3 h, 6 h, 12 h, 24 h, 48 h, 72 h and 96 h to estimate the rate of gas evolution. Gas production in general was influenced by pesticide application. In general, gas evolution was reduced by increasing levels of lambda cyhalothrin up to 80 mg/kg. However, an increase in gas accumulation was observed with increasing levels of dimethoate, while the application of cypermethrin yielded no noticeable change in gas production. The study indicates that pesticide residues may function as toxins at concentrations greater than those encountered in the field or lethal dose (LD50) and may inhibit the growth of rumen microbes.