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Lixivia??o de nitrato em pastagem de coastcross adubada com nitrogênio
Primavesi, Odo;Primavesi, Ana Candida;Corrêa, Luciano de Almeida;Silva, Aliomar Gabriel da;Cantarella, Heitor;
Revista Brasileira de Zootecnia , 2006, DOI: 10.1590/S1516-35982006000300008
Abstract: the goal of this work was to assess nitrate losses in the soil profile. nitrate concentration was determined in the profile of a soil under coastcross pasture (cynodon dactylon cv. coastcross), in s?o carlos, sp, brazil, in the rainy season of two consecutive years. the soil was a dark red latosol (hapludox), affected by tropical altitude climate. nitrogen doses of 125, 250, 500 and 1,000 kg ha-1 year-1, as urea or ammonium nitrate were broadcasted splited in five applications. soil nitrate concentration was determined down to 160 cm depth. in 1999, nitrate level varied according to n sources, reaching higher figure in soil that had received 1,000 kg ha-1 year-1 of n. the highest no3-n concentration occurred in soil layer down to 100 cm depth, in the plots treated with ammonium nitrate. in 2000, nitrate-n was measured weekly in the soil profile, in treatments with 500 and 1,000 kg ha-1 year-1. the greatest variations, from 0 to 81.2 mg kg-1 of no3-n, occurred down to 40 cm depth. results point to low danger of water table contamination in deep medium textured soils of intensively well managed tropical grass pasture, using n doses lower than the forage n cycling capacity and considering the potential soil n sources.
Desempenho de bezerros da ra?a Nelore e cruzados desmamados recebendo concentrado em pastagem adubada de Cynodon dactylon cv. Coastcross
Cruz, Geraldo Maria da;Rodrigues, Armando de Andrade;Tullio, Rymer Ramiz;Alencar, Maurício Mello de;Alleoni, Guilherme Fernando;Oliveira, Gilson Pereira de;
Revista Brasileira de Zootecnia , 2009, DOI: 10.1590/S1516-35982009000100018
Abstract: in three years of research, 223 purebred nelore and crossbred canchim × nelore, angus × nelore and simmental × nelore calves received either mineral mixture or 3 kg/animal/day of a concentrate, containing 18.8% crude protein and 81.5% total digestible nutrients, on a dry basis, while in a rotational grazing of cynodon dactylon cv. coastcross, fertilized pastures. available forage (kg dry matter/ha) was different for paddocks of cattle receiving mineral mixture (2,961 kg) from those receiving concentrate (3,383 kg). however, forage dry matter allowance was higher (9.9 kg/animal/day or 3.9% of bw) for cattle receiving mineral mixture than for cattle receiving concentrate in the diet (9.0 kg/animal/day or 3.3% of bw). available forage had, on a dry basis, 13.6% crude protein, 79.8% neutral detergent fiber, 62.3% in vitro dry matter digestibility, 3.9 g/kg calcium, 2.0 g/kg magnesium, 2.5 g/kg phosphorus, 22.7 g/kg potassium, 2.8 g/kg sulfur, 9.9 mg/kg copper, 22.5 mg/kg zinc, 98 mg/kg manganese and 188 mg/kg iron. statistical interactions of genetic group × supplementation and year × supplementation were observed for average daily gain and for stocking rates while a grazing cycle × supplementation interaction was observed for stocking rates. the average daily gain of nelore, canchim × nelore, angus × nelore and simmental × nelore, receiving mineral mixture in the diet, were 0.48, 0.63, 0.68 and 0.50 kg, respectively, while those animals receiving concentrate in the diet, were 0.87, 0.95, 0.99 and 0.95 kg, in the same order of genetic groups. average stocking rates of pastures grazed by all genetic groups receiving mineral mixture in the diet was 6.1 animal units/ha, while the pastures grazed by nelore, canchim × nelore, angus × nelore and simmental × nelore showed values of 7.5, 7.6, 8.8 and 9.0 animal units/ha, respectively, for animals receiving concentrate in the diet. the genetic group affects performance of cattle grazing coastcross and shows interaction with supp
Structure and nutritive value of Coastcross -1 and “Arachis pintoi” mixed pasture, with or without nitrogen fertilization Estrutura e valor nutritivo da pastagem de Coastcross -1 consorciada com "Arachis pintoi", com e sem aduba o nitrogenada  [cached]
Wagner Paris,Ulysses Cecato,Elias Nunes Martins,Veridiana Aparecida Lim?o
Revista Brasileira de Saúde e Produ??o Animal , 2009,
Abstract: This trial was carried out to evaluate the production and quality of leaf blade (LB), sheath + green stem (SGS), dead material (DE) forage structural constituents of Coastcross and Arachis pintoi whole plant (WPA) mixed pasture, under grazing, during February 2003 and June 2004. The treatments CA0 = Coastcross + Arachis without N; CA100 = Coastcross + Arachis with 100 kg of N; CA200 = Coastcross + Arachis with 200 kg of N and C200 = Coastcross with 200 kg of N were distributed in a randomly block design, with two replicates. Pasture management was done through continuous grazing with variable stocking rate. Analyses of crude protein (CP), neutral detergent fiber (NDF) and dry matter in vitro digestibility (DMIVD) were done to LB, SGS, and WPA. The production of structural constituents varied in agreement with total mass and forage. Coastcross SGS contributed for forage production, and the quality characteristics are acceptable for animal production. Treatments that received nitrogen presented the highest CP values, and similar NDF and DMIVD to treatments without nitrogen. Objetivou-se, com este trabalho, avaliar a produ o e composi o química de forragem nos constituintes estruturais lamina foliar (LF), bainha + colmo verde (BCV), material morto (MM) da Coastcross e da planta inteira de Arachis pintoi (AP) em consorcia o sob pastejo no período de julho de 2003 a junho de 2004. Os tratamentos CA0=Coastcross + Arachis sem N; CA100=Coastcross + Arachis com 100 kg de N/ha/ano; CA200=Coastcross + Arachis com 200 kg de N/ha/ano e C200=Coastcross com 200 kg de N/ha/ano foram distribuídos em um delineamento em blocos ao acaso, com duas repeti es. O manejo do pasto foi por meio de lota o contínua e carga animal variável. Foram realizadas as análises de proteína bruta (PB), fibra em detergente neutro (FDN) e digestibilidade in vitro da matéria seca (DIVMS) da pastagem para LF, BCV e AP. As produ es dos constituintes estruturais variaram de acordo com os períodos experimentais, e os tratamentos com aduba o apresentaram valores superiores de LF, principalmente nos períodos de primavera e ver o. Além da melhor composi o nutricional indicada pelas LF e AP, a BCV da Coastcross expressou características qualitativas aceitáveis para produ o animal. Os tratamentos que receberam nitrogênio apresentaram maiores valores de PB e teores semelhantes de FDN e DIVMS ao tratamento sem nitrogênio.
Root biomass and organic reserves of coastcross intercropping or not with “Arachis pintoi”, with or without nitrogen, under grazing Biomassa radicular e reservas organicas em coastcross consorciada ou n o com "Arachis pintoi", com e sem nitrogênio, sob pastejo
Ossival Lolato Ribeiro,Ulysses Cecato,Augusto Manoel Rodrigues,Juliana Cantos Faveri
Revista Brasileira de Saúde e Produ??o Animal , 2011,
Abstract: The aim of this study was to evaluate the non-structural carbohydrates and root biomass in pastures of Coastcross + Arachis pintoi; Coastcross + Arachis pintoi with 100kg/ha of nitrogen (N); Coastcross + Arachis pintoi with 200kg/ha of N; and Coastcross with 200kg/ha of N, in the seasons of winter, spring, summer and autumn. In the experimental was used a complete randomized block design with subdivided parcels, with two repetitions (blocks) was used. The use of nitrogen fertilization (100kg/ha) associated to the Arachis pintoi provided the highest content of non-structural carbohydrates (0,3942g/hg) in the roots and greater root biomass (0,4483kg/m3). The content of non-structural carbohydrates and the root biomass were higher in the summer and autumn. The concentration of 63%, 24 % and 13% of the root biomass occurred in the layer of 0 - 15; 15 - 30 and 30 - 45cm of the ground, however, it did not have difference in the root biomass between the treatments with or without intercropping, in the studied depths. The concentrations of the non-structural carbohydrates were similar in the different depths of the root. Objetivou-se neste trabalho avaliar a concentra o de carboidrato n o-estrutural e biomassa radicular em pastagens de grama Coastcross + Arachis pintoi; Coastcross + Arachis pintoi com 100kg/ha de nitrogênio (N); Coastcross + Arachis pintoi com 200kg/ha de N; e Coastcross com 200kg/ha de N, nos períodos de ver o, outono e inverno. Utilizou-se delineamento experimental em blocos ao acaso com os tratamentos em esquema de parcelas subdivididas, com duas repeti es (blocos). A utiliza o de aduba o nitrogenada (100kg/ha) associada ao Arachis pintoi proporcionou maior concentra o de carboidrato n o estrutural (0,3942g/hg) na raiz e maior biomassa radicular (0,4483kg/m3). A concentra o de carboidrato n o estrutural e a biomassa radicular foram elevadas no ver o e outono. A concentra o de biomassa radicular foi de 63%, 24% e 13% nas profundidades de 0 - 15, 15 - 30 e 30 - 45cm, entretanto, n o houve diferen a na biomassa radicular entre os tratamentos com e sem consorcia o, nas profundidades estudadas. As concentra es de carboidratos n o estruturais foram semelhantes nas diferentes profundidades das raízes.
Controle de plantas daninhas na cultura do milho com gliricídia em consorcia o Weed control in maize crop with gliricidia intercropping  [cached]
B.B. Araújo Jr.,P.S.L. Silva,O.F. Oliveira,J. Espinola Sobrinho
Planta Daninha , 2012, DOI: 10.1590/s0100-83582012000400010
Abstract: A gliricídia (Gliricidia sepium) é leguminosa perene, cultivada para propósitos múltiplos, que apresenta crescimento rápido e várias substancias com propriedades alelopáticas. Existem indica es de que a consorcia o com gliricídia também pode trazer benefícios no controle das plantas daninhas do milho. O objetivo deste trabalho foi avaliar o controle das plantas daninhas no milho (híbrido duplo AG 1051) com gliricídia em consorcia o. Utilizou-se o delineamento em blocos completos casualizados, com oito repeti es. Os tratamentos consistiram em: cultivo do milho com capinas (duas, aos 20 e 40 dias após a semeadura), sem capinas e em consorcia o com a gliricídia. A gliricídia foi semeada a lan o, com 25 sementes m-2, por ocasi o da semeadura do milho, entre as fileiras deste. Quinze espécies de plantas daninhas foram catalogadas na área experimental, sendo Commelina benghalensis a mais frequente. Os rendimentos de espigas verdes (empalhadas e despalhadas) obtidos com a consorcia o foram iguais ou superiores a 85% dos rendimentos obtidos com capinas. Além disso, o rendimento de gr os no consórcio chegou a 80% do rendimento de gr os do milho capinado. Portanto, a consorcia o com a gliricídia pode ser uma alternativa viável para as produ es de milho verde e de gr os, embora essa consorcia o n o tenha influenciado a densidade e a biomassa seca das plantas daninhas. Gliricidia (Gliricidia sepium), a perennial leguminous species presenting fast growth and several allelopathic substances, is cultivated for multiple purposes. There are good evidences that gliricidia intercropped with maize efficiently controls weeds. This work aimed to evaluate the use of gliricidia intercropped with maize as a method of weed control in maize (hybrid AG 1051). The experiment was carried out in a randomized complete block design with eight replications. The treatments consisted of: maize cropping with hand-hoeing weed control (at 20 and 40 days after sowing); no weed control; and intercropping with gliricidia. Gliricidia was sown in-rows using 25seedsm-2 after maize sowing. Fifteen weed species were found and classified in the experimental area, with the most frequent one being Commelina benghalensis. Green ear yield (with husk and without husk) obtained with intercropping was equal to, or greater than 85% of the yields obtained with weeding. In addition, the grain yield from intercropping reached 80% of grain yield of the corn weeded. Therefore, intercropping maize-gliricidia may be a viable alternative for the production of green corn and grain, although it did not influe
Produ??o animal e valor nutritivo da forragem de pastagem de coastcross consorciada com amendoim forrageiro
Barbero, L.M.;Cecato, U.;Lug?o, S.M.B.;Gomes, J.A.N.;Lim?o, V.A.;Abrah?o, J.J.S.;Roma, C.F.C.;
Arquivo Brasileiro de Medicina Veterinária e Zootecnia , 2010, DOI: 10.1590/S0102-09352010000300021
Abstract: in this study, the following treatments were used: coastcross + forage peanut + 200kg/ha of n; coastcross + forage peanut + 100kg/ha of n; coastcross + 200kg/ha of n and coastcross + forage peanut (plots) in the winter, spring, summer, and autumn (subplots), designed in randomized blocks. heifers were managed under continuous stocking and variable stocking rate on pasture maintained at 17cm height. samples were collected every 28 days determining the nutritional value of forage. average daily gain (adg), weight gain (wg), stocking rate (sr), and number of animals/day (nad) were evaluated. as for forage nutritional value, the worst results were found in pasture without fertilization, 16.9% and 6.0% cp of leaf and stem, respectively, and 70.1% ndf in leaves. in the spring and summer, animals had a higher adg, 0.518 and 0.515kg/animal, than 0.396 and 0.293kg/animal in the winter and autumn, respectively. sr was higher in pastures that received higher nitrogen doses, 5.38au/ha in average; and in the summer, 6.81au/ha. lwg was higher in fertilized areas, 1,341kg lw/ha, than in not fertilized pastures, 735kg/ha.
Produ??o de forragem e componentes morfológicos em pastagem de coastcross consorciada com amendoim forrageiro
Barbero, Leandro Martins;Cecato, Ulysses;Lug?o, Simony Marta Bernardo;Gomes, José Augusto Nogueira;Lim?o, Veridiana Aparecida;Basso, Kelen Cristina;
Revista Brasileira de Zootecnia , 2009, DOI: 10.1590/S1516-35982009000500002
Abstract: this experiment was carried out from july 2006 to june 2007. it was used an experimental design of random blocks with split plot in time, with two replications using the following treatments: coastcross + peanut forage + 200 kg/ha of n; coastcross + peanut forage + 100 kg/ha of n; coastcross + 200 kg/ha of n and coastcross + peanut forage in the following seasons: winter, spring, summer and autumn. to estimate the forage mass production availability, the double sampling and triple pairing technique, respectively, every 28 days was used. the proportions of grass, legumes, weeds, uncovered soil and litter were evaluated. the material from the double sampling technique was separated into leaf blade, stem + sheath and dead material fractions. regarding of forage availability, the pasture submitted to treatment without nitrogen had the lower mass, while that submitted to 200 kg/ha of nutrient without the presence of legume had the highest forage mass. for the peanut forage mass, the pasture without fertilization presented the best result. the forage production was higher in pastures submitted to treatment with 200 kg of n/ha followed by that fertilized with 100 kg of n/ha. the grass accumulation rate followed the same trend of forage production. no difference were observed for uncovered soil, litter and uncovered area between treatments; however, the pasture submitted to the dose of 200 kg of n/ha without legume presented lower incidence of invasive plants. no differences were observed for the leaf/stem ratio, leaves mass and dead material mass between treatments; however, the grass submitted to 200 kg of n/ha without legume presented the greatest stems mass.
Produ??o e qualidade de pastagens de Coastcross-1 e milheto utilizadas com vacas leiteiras
Scaravelli, Luciene Fernanda Barros;Pereira, Lilian Elgalise Techio;Olivo, Clair Jorge;Agnolin, Carlos Alberto;
Ciência Rural , 2007, DOI: 10.1590/S0103-84782007000300037
Abstract: the use of pastures of the genus cynodon has increased, for the last decade especially in dairy properties of rio grande do sul. this research aims to compare the dynamic, dry matter production, quality and botanical composition of coastcross-1 (cynodon dactylon x c. nlemfluensis) and pearl millet (pennisetum americanum) cv. comum pastures. the pastures were utilized by lactating holstein dairy cows under rotational stocking system. pregraze dry matter availability (dma), daily dry matter accumulation rate (dmr), total dry matter production (tdm) were evaluated. for the botanical composition, the structural components: leaf blade (lb), stem + sheat (ss), dead material (dmt) of pastures and other species (os) were evaluated. before and after grazing, samples were collected by hand-plucking in order to determine the crude protein concentration (cp) and neutral detergent fiber (ndf). no significant difference (p>.05) was observed to dma, dmr, tdm and cp. pearl millet presented greater availability of lb (p<.05), smaller ndf (p<.05) in pregraze and postgraze herbage mass and greater contribution of os (p<.05). the total grazing period was greater in coastcross-1 pasture.
Produ??o de forragem e carga animal de pastagens de Coastcross sobressemeadas com forrageiras de inverno
Olivo, Clair Jorge;Meinerz, Gilmar Roberto;Agnolin, Carlos Alberto;Steinwandter, Edilene;Ziech, Magnos Fernando;Skonieski, Fernando Reimann;
Revista Brasileira de Zootecnia , 2010, DOI: 10.1590/S1516-35982010000100009
Abstract: the objective of this research was to evaluate the forage production and stocking rate (sr) of four coastcross (cynodon dactylon l. pers.) pastures overseeded with ryegrass (lolium multiflorum lam. cv. common); ryegrass plus white clover (trifolium repens l., cv. yi) over bermudagrass; ryegrass plus white clover and ryegrass. the experiment was carried out from may 15 to october 24, 2006, in five grazing periods. holstein cows receiving 3.5 kg/daily complementary concentrate feed were used in the evaluation. in the pre and post grazing periods, the forage mass, botanical and structural pasture composition and the stocking rate were assessed. a randomized complete design was used, with four treatments (pastures) and two replications (paddocks), in five grazing cycles. no differences in herbage mass and stocking rate averages were detected among pastures. the ryegrass pastures had larger ryegrass leaf blade herbage mass production. the overseeded pastures had larger forage production. overseeding with ryegrass and white clover on coastcross extend the use period of annual grass and increase forage production.
Produ o e qualidade de massa de forragem nos estratos da cultivar coastcross-1 consorciada com Arachis pintoi com e sem aduba o nitrogenada = Forage mass production and quality in coastcross-1 pasture layers, mixed with Arachis pintoi with or without nitrogen fertilization
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Acta Scientiarum : Animal Sciences , 2008,
Abstract: Neste trabalho, objetivou-se avaliar a massa de forragem nas fra es laminas foliares (LF), bainha + colmo verde (BCV), material morto (MM) e seus teores de proteína bruta (PB) e fibra em detergente neutro (FDN) nos estratos de 0 a 7 cm, 7 a 14 cm e acima de 14 cm de altura da cultivar Coastcross-1 e planta inteira de Arachis pintoi (AP) em pastejo, de mar o de 2003 a mar o de 2004. Estudaram-se os efeitos dos tratamentos CA0 = Coastcross-1 + Arachis sem N; CA100 = Coastcross-1 + Arachis com 100 kg de N; CA200 = Coastcross-1 + Arachis com 200 kg de N e C200 = Coastcross-1 com 200 kg deN, em um delineamento em blocos ao acaso, com duas repeti es. O método de pastejo foi contínuo e a taxa de lota o, variável. As propor es de LF da gramínea Coastcross-1 aumentaram e de BCV, MM e AP diminuíram com o aumento da altura. N o foram observadas diferen as entre os tratamentos. A planta inteira da leguminosa Arachis teve pouca influência na composi o da pastagem pela sua baixa disponibilidade. Os maiores (p < 0,05) valores para PB e menores para FDN foram observados nos estratos intermediários e superiores. O tratamento sem aduba o apresentou valor de PB inferior(p < 0,05) aos demais tratamentos adubados. This trial was carried out to evaluate forage mass in fraction leaf blade (LB), sheath + green stem (SGS), dead material (DE), and crude protein (CP) percentage and neutral detergent fiber (NDF) in thelayers of 0 to 7 cm, 7 to 14 cm and over 14 cm high. Coastcross-1 grass and the whole plant of Arachis pintoi (WPA) were evaluated under grazing, from March 2003 to March 2004. The treatments evaluated were CA0 = Coastcross-1 + Arachis without N; CA100= Coastcross-1 + Arachis with 100 kg of N; CA200 = Coastcross-1 + Arachis with 200 kg of N; and C200 = Coastcross-1 with 200 kg of N, in a random block design, with two repetitions. The proportion of LB and SGS increased, while DE and WPA decreased with the increase of clipping height. No difference was observed among treatments. Arachis had little influence on pasture composition because of its low availability. The highest values (p < 0.05) for CP and the lowest values for NDF were observed in the intermediate and upper layers.
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