Made available in DSpace on 2016-04-28T14:59:47Z (GMT). No. of bitstreams: 1 2009 - Elio Barbieri Junior.pdf: 7095685 bytes, checksum: 1bcdc77a8d686ebd516a400693c004ae (MD5) Previous issue date: 2009-02-20 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Among the biochemical properties related to the use of nitrogen (N) for the plants, chlorophyll pigments occupy a relevant position. For that reason, and given the importance of the N fertilization for pasture productivity, it has been developed methodologies that allow determining leaf chlorophyll contents for indirect and non destructive procedures. With the purpose of supplying subsidies for N fertilization management in in pastures of Cynodon spp. cv. Tifton 85 was installed an experiment with purpose of verifying the performance of a commercial chlorophyll meter. The experimental strategy consisted of the induction of three levels of soil N availability, through N fertilization. The working hypotheses were the following ones: i) different soil N availabilities result in differentiated leaf chlorophyll contents in leaves recently emerged and fully expanded; ii) readings obtained with a chlorophyll meter are related with foliar Total chlorophyll contents; iii) chlorophyll contents are related with foliar N concentrations; e iv) chlorophyll content indicators keep relationship with green dry matter production. This study was carried out on a Haplic Planosol at the Experimental Campus of the Rural Federal University of Rio de Janeiro, Serop?dica, RJ, during the period of July to December 2008. An entirely randomized block design was used, with four repetitions. Main treatments were allocated in plots (4x4 m) and consisted of three N fertilization levels (0; 75 and 150kg N-ur?ia). Four sampling dates designed as days from a standardization cut made 131days after planting were allocated in sub-plots. Three of the sampling dates (8, 16 and 24 days) were pre-fixed, while the last was accomplished when the sward interception level of photosynthetically active radiation reached a value of 95%. Structural dynamics was followed by monitoring the following canopy variables: sward height; tiller density, leaf area index, green cover index and green dry mass accumulation. Chlorophylls a, b and (a+b) were measured always in the first fully expanded leaves of sun tillers by the Arnon method with modifications, and indirectly, with the chlorophyll meter ClorofiLOG?. In the same type of leaves, total N content was determined by Kjeldhal routine procedures. Principal results showed that concentrations of chlorophylls a, b and (a + b) in Tifton leaf blades were affected by nitrogen fertilization and sampling dates reaching maximal differences at the 24th day after cut. Chlorophyll meter readings (Falker Chlorophyll Index, FCI) and foliar N contents also responsed very sensibly to N rates, reaching maximal values at the16th day after cut. In the same day, Total chlorophyll contents and Total N leaf contents were also significantly correlated with FCI values, with r2 coefficients of 0,93 and 0,89 respectively. Correlation coefficient between total green dry matter and FCI values was 0,867. Total green dry matter accumulation at the last sampling date and FCI readings at 16th day after cut also resulted significantly related (r2 = 0,72), a promising relation for purposes of forage yield estimation. In conclusion, the obtained results allow affirming that, in Tifton 85, total chlorophyll content present in the first leaf totally expanded is a sensitive marker of soil N availability and therefore of N fertilization needs. Total chlorophyll content through its relationship with leaf N contents may be also a valuable tool for foliar N diagnosis. Both attributes were discriminated properly by the chlorophyll meter under evaluation. This apparatus maximized its performance in the period were happened Among the biochemical properties related to the use of nitrogen (N) for the plants, chlorophyll pigments occupy a relevant position. For that reason, and given the importance of the N fertilization for pasture productivity, it has been developed methodologies that allow determining leaf chlorophyll contents for indirect and non destructive procedures. With the purpose of supplying subsidies for N fertilization management in in pastures of Cynodon spp. cv. Tifton 85 was installed an experiment with purpose of verifying the performance of a commercial chlorophyll meter. The experimental strategy consisted of the induction of three levels of soil N availability, through N fertilization. The working hypotheses were the following ones: i) different soil N availabilities result in differentiated leaf chlorophyll contents in leaves recently emerged and fully expanded; ii) readings obtained with a chlorophyll meter are related with foliar Total chlorophyll contents; iii) chlorophyll contents are related with foliar N concentrations; e iv) chlorophyll content indicators keep relationship with green dry matter production. This study was carried out on a Haplic Planosol at the Experimental Campus of the Rural Federal University of Rio de Janeiro, Serop?dica, RJ, during the period of July to December 2008. An entirely randomized block design was used, with four repetitions. Main treatments were allocated in plots (4x4 m) and consisted of three N fertilization levels (0; 75 and 150kg N-ur?ia). Four sampling dates designed as days from a standardization cut made 131days after planting were allocated in sub-plots. Three of the sampling dates (8, 16 and 24 days) were pre-fixed, while the last was accomplished when the sward interception level of photosynthetically active radiation reached a value of 95%. Structural dynamics was followed by monitoring the following canopy variables: sward height; tiller density, leaf area index, green cover index and green dry mass accumulation. Chlorophylls a, b and (a+b) were measured always in the first fully expanded leaves of sun tillers by the Arnon method with modifications, and indirectly, with the chlorophyll meter ClorofiLOG?. In the same type of leaves, total N content was determined by Kjeldhal routine procedures. Principal results showed that concentrations of chlorophylls a, b and (a + b) in Tifton leaf blades were affected by nitrogen fertilization and sampling dates reaching maximal differences at the 24th day after cut. Chlorophyll meter readings (Falker Chlorophyll Index, FCI) and foliar N contents also responsed very sensibly to N rates, reaching maximal values at the16th day after cut. In the same day, Total chlorophyll contents and Total N leaf contents were also significantly correlated with FCI values, with r2 coefficients of 0,93 and 0,89 respectively. Correlation coefficient between total green dry matter and FCI values was 0,867. Total green dry matter accumulation at the last sampling date and FCI readings at 16th day after cut also resulted significantly related (r2 = 0,72), a promising relation for purposes of forage yield estimation. In conclusion, the obtained results allow affirming that, in Tifton 85, total chlorophyll content present in the first leaf totally expanded is a sensitive marker of soil N availability and therefore of N fertilization needs. Total chlorophyll content through its relationship with leaf N contents may be also a valuable tool for foliar N diagnosis. Both attributes were discriminated properly by the chlorophyll meter under evaluation. This apparatus maximized its performance in the period were happenedAmong the biochemical properties related to the use of nitrogen (N) for the plants, chlorophyll pigments occupy a relevant position. For that reason, and given the importance of the N fertilization for pasture productivity, it has been developed methodologies that allow determining leaf chlorophyll contents for indirect and non destructive procedures. With the purpose of supplying subsidies for N fertilization management in in pastures of Cynodon spp. cv. Tifton 85 was installed an experiment with purpose of verifying the performance of a commercial chlorophyll meter. The experimental strategy consisted of the induction of three levels of soil N availability, through N fertilization. The working hypotheses were the following ones: i) different soil N availabilities result in differentiated leaf chlorophyll contents in leaves recently emerged and fully expanded; ii) readings obtained with a chlorophyll meter are related with foliar Total chlorophyll contents; iii) chlorophyll contents are related with foliar N concentrations; e iv) chlorophyll content indicators keep relationship with green dry matter production. This study was carried out on a Haplic Planosol at the Experimental Campus of the Rural Federal University of Rio de Janeiro, Serop?dica, RJ, during the period of July to December 2008. An entirely randomized block design was used, with four repetitions. Main treatments were allocated in plots (4x4 m) and consisted of three N fertilization levels (0; 75 and 150kg N-ur?ia). Four sampling dates designed as days from a standardization cut made 131days after planting were allocated in sub-plots. Three of the sampling dates (8, 16 and 24 days) were pre-fixed, while the last was accomplished when the sward interception level of photosynthetically active radiation reached a value of 95%. Structural dynamics was followed by monitoring the following canopy variables: sward height; tiller density, leaf area index, green cover index and green dry mass accumulation. Chlorophylls a, b and (a+b) were measured always in the first fully expanded leaves of sun tillers by the Arnon method with modifications, and indirectly, with the chlorophyll meter ClorofiLOG?. In the same type of leaves, total N content was determined by Kjeldhal routine procedures. Principal results showed that concentrations of chlorophylls a, b and (a + b) in Tifton leaf blades were affected by nitrogen fertilization and sampling dates reaching maximal differences at the 24th day after cut. Chlorophyll meter readings (Falker Chlorophyll Index, FCI) and foliar N contents also responsed very sensibly to N rates, reaching maximal values at the16th day after cut. In the same day, Total chlorophyll contents and Total N leaf contents were also significantly correlated with FCI values, with r2 coefficients of 0,93 and 0,89 respectively. Correlation coefficient between total green dry matter and FCI values was 0,867. Total green dry matter accumulation at the last sampling date and FCI readings at 16th day after cut also resulted significantly related (r2 = 0,72), a promising relation for purposes of forage yield estimation. In conclusion, the obtained results allow affirming that, in Tifton 85, total chlorophyll content present in the first leaf totally expanded is a sensitive marker of soil N availability and therefore of N fertilization needs. Total chlorophyll content through its relationship with leaf N contents may be also a valuable tool for foliar N diagnosis. Both attributes were discriminated properly by the chlorophyll meter under evaluation. This apparatus maximized its performance in the period were happened Among the biochemical properties related to the use of nitrogen (N) for the plants, chlorophyll pigments occupy a relevant position. For that reason, and given the importance of the N fertilization for pasture productivity, it has been developed methodologies that allow determining leaf chlorophyll contents for indirect and non destructive procedures. With the purpose of supplying subsidies for N fertilization management in in pastures of Cynodon spp. cv. Tifton 85 was installed an experiment with purpose of verifying the performance of a commercial chlorophyll meter. The experimental strategy consisted of the induction of three levels of soil N availability, through N fertilization. The working hypotheses were the following ones: i) different soil N availabilities result in differentiated leaf chlorophyll contents in leaves recently emerged and fully expanded; ii) readings obtained with a chlorophyll meter are related with foliar Total chlorophyll contents; iii) chlorophyll contents are related with foliar N concentrations; e iv) chlorophyll content indicators keep relationship with green dry matter production. This study was carried out on a Haplic Planosol at the Experimental Campus of the Rural Federal University of Rio de Janeiro, Serop?dica, RJ, during the period of July to December 2008. An entirely randomized block design was used, with four repetitions. Main treatments were allocated in plots (4x4 m) and consisted of three N fertilization levels (0; 75 and 150kg N-ur?ia). Four sampling dates designed as days from a standardization cut made 131days after planting were allocated in sub-plots. Three of the sampling dates (8, 16 and 24 days) were pre-fixed, while the last was accomplished when the sward interception level of photosynthetically active radiation reached a value of 95%. Structural dynamics was followed by monitoring the following canopy variables: sward height; tiller density, leaf area index, green cover index and green dry mass accumulation. Chlorophylls a, b and (a+b) were measured always in the first fully expanded leaves of sun tillers by the Arnon method with modifications, and indirectly, with the chlorophyll meter ClorofiLOG?. In the same type of leaves, total N content was determined by Kjeldhal routine procedures. Principal results showed that concentrations of chlorophylls a, b and (a + b) in Tifton leaf blades were affected by nitrogen fertilization and sampling dates reaching maximal differences at the 24th day after cut. Chlorophyll meter readings (Falker Chlorophyll Index, FCI) and foliar N contents also responsed very sensibly to N rates, reaching maximal values at the16th day after cut. In the same day, Total chlorophyll contents and Total N leaf contents were also significantly correlated with FCI values, with r2 coefficients of 0,93 and 0,89 respectively. Correlation coefficient between total green dry matter and FCI values was 0,867. Total green dry matter accumulation at the last sampling date and FCI readings at 16th day after cut also resulted significantly related (r2 = 0,72), a promising relation for purposes of forage yield estimation. In conclusion, the obtained results allow affirming that, in Tifton 85, total chlorophyll content present in the first leaf totally expanded is a sensitive marker of soil N availability and therefore of N fertilization needs. Total chlorophyll content through its relationship with leaf N contents may be also a valuable tool for foliar N diagnosis. Both attributes were discriminated properly by the chlorophyll meter under evaluation. This apparatus maximized its performance in the period were happened the highest leaf N content and linking directly with final green dry matter accumulation. / Dentre as propriedades bioqu?micas relacionadas ? utiliza??o do nitrog?nio (N) pelas plantas, os teores de clorofila ocupam posi??o de destaque. Por essa raz?o, e dada a import?ncia que a aduba??o nitrogenada tem na express?o da produtividade das pastagens, tem sido desenvolvidas metodologias que permitem a determina??o do teor de clorofila por procedimentos indiretos e n?o destrutivos. No intuito de fornecer subs?dios para a defini??o de estrat?gias de aduba??o nitrogenada em pastagens de Cynodon spp. cv. Tifton 85 foi instalado um experimento com o prop?sito primordial de verificar o desempenho de um clorofil?metro comercial. Foi utilizada uma estrat?gia experimental consistente na indu??o de tr?s n?veis de disponibilidade de N no solo, atrav?s de aduba??o nitrogenada. As hip?teses que guiaram o experimento foram as seguintes: i) n?veis diferenciados de N no solo, resultam em teores diferenciados de clorofila em folhas rec?m emergidas; ii) leituras obtidas com um clorofil?metro guardam rela??o com os teores foliares das clorofilas; iii) teores de clorofila total relacionam-se com os teores foliares de N; e iv) os indicadores ligados ? clorofila foliar guardam rela??o com a produ??o de mat?ria seca. O experimento foi desenvolvido sobre um Planossolo H?plico, no campo experimental da Universidade Federal Rural do Rio de Janeiro, munic?pio de Serop?dica, RJ, durante o per?odo de julho a dezembro de 2008. O experimento foi disposto segundo um desenho em blocos inteiramente casualizados, com quatro repeti??es. Os tratamentos, alocados nas parcelas (4x4m), consistiram de tr?s n?veis de N (0; 75 e 150kg N-ur?ia/ha), enquanto que nas sub-parcelas, foram alocadas quatro dias de coletas, contados a partir um corte de uniformiza??o, realizado 131 dias ap?s o plantio do capim. Tr?s das datas de amostragem foram pre-fixadas, aos 8, 16 e 24 dias, enquanto a ?ltima foi realizada quando a pastagem atingiu um n?vel de intercepta??o de 95% da radia??o fotossint?ticamente ativa incidente. A din?mica estrutural foi acompanhada atrav?s da mensura??o das seguintes vari?veis do dossel: altura; densidade populacional de perfilhos; ?ndice de ?rea foliar, ?ndice de cobertura verde, e ac?mulo de massa verde seca. As clorofilas a, b, e (a+b), foram quantificadas, sempre em primeiras folhas completamente expandidas de perfilhos de sol, pelo m?todo de Arnon modificado, e indiretamente, com um aparelho ClorofiLOG?. Os teores de N total foram determinados nas mesmas folhas, pelo m?todo de Kjeldhal. Os resultados mostraram que os teores de clorofila a, b e (a+b) diferiram entre doses de N, e dias de amostragem, atingindo diferen?as m?ximas entre as doses de N aos 24 dias ap?s corte. As leituras do clorofil?metro (?ndice de Clorofila Falker, ICF) e os teores de N foliar tamb?m responderam sensivelmente ?s doses de N, atinguindo valores m?ximos aos 16 dias. Nesse mesmo dia, a an?lise de regress?o linear entre os teores de clorofila total e de N total, contra os respectivos valores de ICF resultou em coeficientes de determina??o de 0,93 e 0,89 respectivamente. O coeficiente de correla??o entre a massa verde seca total e os valores de ICF foi de 0,867. O ac?mulo de mat?ria verde seca total aos 28 dias ap?s o corte relacionouse linearmente com as leituras do clorofil?metro feitas aos 16 dias (r2=0,72), um tipo de resultado promissor em termos de estimativas de disponibilidade de forragem. Como conclus?o, os resultados permitiram verificar que os teores de clorofila total presentes na primeira folha totalmente expandida, responderam ? aplica??o de doses diferenciadas de N e se relacionaram estreitamente com os teores de N foliar. Ambos os atributos foram discriminados de forma precisa pelo clorofil?metro sob avalia??o. Este aparelho maximizou o seu desempenho no per?odo onde ocorreram os m?ximos teores de N foliar, relacionando-se diretamente com a mat?ria seca acumulada no final do per?odo de rebrota.

Made available in DSpace on 2016-04-28T14:59:45Z (GMT). No. of bitstreams: 1 2008 - Ana Paula Pessim de Oliveira.pdf: 1134139 bytes, checksum: e35252b70432f1b09c9e114425df2810 (MD5) Previous issue date: 2008-07-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The effects of nitrogen (N) application on several structural and nutritional attributes of the plant canopy were evaluated. The studies were carried out at the Experimental Campus of the Rio de Janeiro Federal Rural University, Serop?dica-RJ, in area of Planosol Haplic occurrence, during the period of October 2006 to July 2007. Treatments consisted of five doses of N (0; 150; 300; 450 and 600 kg N-urea/ha) disposed in experimental units of 4 x 4 m using a entirely randomized block design. After a standardization cut, made 82 days after planting, it proceeded to the application of nitrogen fertilizer levels, half of which at 94 days, and the remaining at 139 days after the planting. Four studies had been carried through, which the results are presented in distinct chapters. In the first chapter the results of nitrogen fertilization were discussed in terms of soil covering, leaf area index (LAI) and solar radiation interception, during the four sequential cuts, between the months of February and July of 2007. Weekly evaluations were accomplished, between 10 and 40 days after cut. The LAI frequency of occurrence, plant height, green cover index and level of photosynthetically active radiation intercepted showed significant responses to N fertilization, according to a logistic pattern and also varied seasonally within each cut, evidencing different sensibility as indicators for structure and growth of the Tifton 85 sward. In the second study were evaluated the effect of N fertilization on biomass production and the efficiency in the use of N absorbed. For statistical analysis purposes, sampling data were clustered in two seasons: rainy season (February to April) and dry season (April to July). It was quantified in each cut date the production of green and dry mass, leaves and stem fraction, as well as the N content in each one of the vegetative fractions. This study showed that N fertilization icreased the dry matter production and stimulated the production of leaves and stems in both the seasons (rainy and dry). However, the nitrogen fertilization, per se, does not modify the partition of the dry mass produced by leaves and stems, and had no influence on efficiency of the pasture to produce dry matter per unit of N absorbed. The third study, of methodological character, aimed the validation of indirect procedures for estimate the functional relation between the green and dry mass and the LAI. The occurrence frequency and the index of green covering were tested as substitutes of IAF using simple correlation procedure. Although in this study has been observed the existence of a significant association among the the canopy attributes estimates associated to the leaf area and the forage production leaf area and forage production, additional studies are necessary to improve the reliability and accuracy of this estimates. Finally, in the last study, the influence of the nitrogen fertilization on nutritional value of the forage was evaluated. The crude protein, neutral detergent fiber, acid detergent fiber, lignin, cellulose and hemicelulose cotents were determined. The results showed that the addition of N improved the forage quality, increasing crude protein contents and decreasing fibrous fraction. / Foram avaliados os efeitos da aplica??o de nitrog?nio (N) sobre uma s?rie de atributos estruturais e nutricionais do dossel. Os estudos foram desenvolvidos no campo experimental da Universidade Federal Rural do Rio de Janeiro, munic?pio de Serop?dica- RJ, em ?rea de ocorr?ncia de Planossolo. O experimento foi conduzido sob regime de cortes, durante o per?odo de outubro de 2006 a julho de 2007. Foram estudadas cinco doses de N (0; 150; 300; 450 e 600 kg/ha) em diferentes ?pocas do ano. O experimento foi conduzido em blocos inteiramente casualizados. Foram feitos quatro estudos, cujos resultados s?o apresentados em cap?tulos distintos. No primeiro cap?tulo, os efeitos da aduba??o nitrogenada s?o discutidos em termos de cobertura do solo, ?ndice de ?rea foliar e intercepta??o da radia??o solar, no curso de quatro cortes seq?enciais, entre os meses de fevereiro e julho. As avalia??es foram realizadas, semanalmente, entre o 10o e o 40o dia ap?s o corte. Em cada corte, o ?ndice de ?rea foliar (IAF), a freq??ncia de ocorr?ncia, altura de planta, ?ndice de cobertura verde e o n?vel de radia??o fotossinteticamente ativa interceptada, responderam ? aduba??o nitrogenada, conforme um padr?o log?stico e variaram sazonalmente, evidenciando uma sensibilidade diversa como indicadores da estrutura e do crescimento da pastagem de Tifton 85. No segundo estudo foram abordadas as respostas relativas ? produ??o de biomassa sob aduba??o nitrogenada e a efici?ncia na utiliza??o do N absorvido. Para efeito de an?lise estat?stica, os dados das coletas foram agrupados em ?poca das chuvas (fevereiro a abril) e ?poca seca (abril a julho). Em cada data de corte foi quantificada a produ??o de massa verde e seca, a sua parti??o entre folhas e colmos + bainhas, assim como o teor de N em cada uma das partes vegetativas. Este estudo evidenciou que a aduba??o nitrogenada aumentou a produ??o de forragem, estimulando a produ??o de folhas e colmos tanto na ?poca chuvosa quanto na seca. Por outro lado, a aduba??o nitrogenada, per se, n?o modificou a parti??o da massa seca produzida por folhas e colmos, nem influenciou a efici?ncia com a qual a pastagem produz massa seca por unidade de nitrog?nio absorvido. O terceiro estudo, de cunho metodol?gico, objetivou a valida??o de procedimentos indiretos para a estimativa da rela??o funcional entre a massa verde e seca e o ?ndice de ?rea foliar da pastagem. Foram estudados a freq??ncia de ocorr?ncia e o ?ndice de cobertura verde como suced?neos do IAF, utilizando-se correla??o simples. Embora tenha sido observada a exist?ncia de um grau de associa??o significativo entre as estimativas de atributos ligados ? ?rea foliar e a produ??o de forragem, s?o necess?rios estudos adicionais para melhorar a confiabilidade e a acur?cia de tais estimativas. No quarto estudo foi estudada a influencia da aduba??o nitrogenada sobre o valor nutricional da forragem, sendo avaliados os teores de prote?na bruta, fibra em detergente neutro, fibra em detergente ?cido, lignina, celulose e hemicelulose. Os resultados obtidos mostraram que a adi??o de N melhorou a qualidade da forragem, aumentando os teores de prote?na bruta e reduzindo a fra??o fibrosa.

O presente trabalho teve como objetivo avaliar o efeito do emurchecimento da forragem associado ou não ao uso do aditivo bacteriano-enzimático na ensilagem do capim Tifton 85 (Cynodon spp.). Foi realizada avaliação de perdas nos painéis das silagens experimentais, assim como da composição bromatológica e do tamanho de partículas das mesmas. Ocorreram observações periódicas de comportamento ingestivo, consistência ruminal, consumo voluntário, parâmetros de fermentação ruminal, digestibilidade dos nutrientes, taxa de passagem de sólidos e líquidos ruminais em novilhos que receberam rações contendo 80% desses volumosos na base seca. Foram utilizados sete novilhos da raça Nelore, distribuídos ao acaso em um experimento do tipo quadrado latino 7 x 7. Os tratamentos avaliados foram resultantes da combinação de 3 concentrações de matéria seca (MS) na silagem do capim Tifton 85 (25, 45 e 65%) associadas (CA) ou não (SA) ao aditivo bacteriano-enzimático. Um tratamento adicional contendo 55% MS sem aditivo também foi avaliado. O aditivo utilizado foi o produto comercial SIL-ALL®, contendo cepas de Streptococcus faecium, Lactobacillus plantarum, Pediococcus acidilactici e as enzimas hemicelulase, celulase e amilase, aplicadas na dosagem de 250 g de SIL-ALL® diluídas em 50 litros de água por tonelada de forragem, imediatamente antes da ensilagem. A técnica de emurchecimento possibilitou elevar o teor de matéria seca mas, da mesma maneira que a adição do inoculante bacteriano-enzimático, provocou alterações pouco pronunciadas na composição química da silagem. Nas silagens SA o aumento da concentração de MS foi acompanhado de elevação no teor de FDN resultando em redução do teor de carboidratos não fibrosos (CNF). A fração protéica B3 nas silagens apresentou tendência de aumento com a elevação na concentração de MS, em função da progressiva elevação da fração N insolúvel no FDN, simultaneamente à redução N insolúvel no FDA. A avaliação dos silos após abertura, indicou aumento de perdas com a elevação da concentração de MS que, entretanto, podem ter sido decorrentes de uma menor taxa de utilização dos fardos contendo silagens com menor umidade. Tanto a consistência ruminal, avaliada como o tempo de ascensão do pêndulo no interior do rúmen (1194 seg.), como os parâmetros de cinética de passagem de sólidos (3,09% hora -1 ) e de líquidos (4,37% hora -1 ) foram similares para os tratamentos avaliados. O comportamento ingestivo dos animais não foi alterado com a elevação da concentração de MS da silagem, sendo observados tempos (minutos dia -1 ) e taxas (min kg MS -1 ) de ingestão de MS (324; 47), ruminação (518; 75) e mastigação (841; 123), respectivamente. O consumo diário de MS das rações, pelos animais, foi semelhante para os tratamentos avaliados, resultando em média de 6,95 kg equivalente a 1,88% do peso corpóreo. As concentrações molares (mM) individuais e totais (140,29) dos ácidos graxos voláteis, a relação acetato:propionato (4,2:1), concentração de nitrogênio amoniacal (6,31 mg dL -1 ) e o pH (6,76), do fluido ruminal, não foram alterados pelos tratamentos estudados. As digestibilidades da matéria orgânica (71,5%), proteína bruta (69,1%), FDN (71,3%), FDA (64,9%) e hemicelulose (83,3%) não foram, em geral, fortemente influenciadas pela concentração de MS da silagem do capim Tifton 85, aditivadas ou não. No entanto, a digestibilidade da MS (71,0%) apresentou um comportamento quadrático (P<0,05), com ligeira elevação ao redor de 45% de concentração de MS, nas silagens. Diante destas observações, pode-se concluir que o emurchecimento da forragem e o uso de aditivo bacteriano-enzimático não resultaram em alterações expressivas nos parâmetros ruminais, digestivos e no comportamento ingestivo dos animais. / The present trial aimed to study the effects of forage wilting associated or not with a bacterial-enzymatic inoculant on ensiling Tifton 85 grass. Front panel of experimental silos (325 kg square wrapped bales) were daily scored for fungi development and weekly sampled for chemical composition analysis and particle chop length measurements. In a randomized 7 x 7 Latin square design, seven ruminal cannulated growing beef steers were assigned to diets (treatments) containing 80% silage. Periodically chewing behavior, feed intake, ruminal mat consistency, ruminal fermentation parameters, nutrient digestibility and ruminal rate of passage of solids and liquids phases were evaluated. Treatments combined 3 planned dry matter (DM) concentrations (25, 45 and 65%) of Tifton 85 grass silage associated (CA) or not (SA) with the bacterial-enzymatic (BE) inoculant source. An additional treatment containing wilted silage (55% DM) without (BE) was also studied. SIL-ALL®, the BE source used, was sprayed onto chopped forage just before silage packing at a rate of 250g diluted in 50L of deionized water per ton of wet forage. The commercial BE showed the following composition: Streptococus faecium, Lactobacillus plantarum, Pediococcus acidilactici plus hemicellulase, cellulase and starch degrading enzymes. The wilting of forage allowed to increase the DM concentration of silages, however, as well as BE addition, it was not effective to promote major changes on chemical composition of silages. On SA silages, higher NDF levels were observed as the DM level of the wilted silage increased, which resulted in lower non-fiber carbohydrate (NFC) fraction. The B3 protein fraction (NDIN minus ADIN) showed an increase as the DM concentration of wilted silage was raised, probably as result of an opposite trend between neutral detergent insoluble nitrogen (NDIN) and acid detergent insoluble nitrogen (ADIN) across DM levels. Silage losses, measured as both, fungi scored at bale front panel and percentage of spoiled silage, indicated higher levels associated with increased DM concentration. It might be explained by the lower bale unloading rate observed during the feeding trial, mainly in higher DM wilted silages. Both, ruminal mat consistency, measured as time required to weight ascension into the rumen (1194 sec.) as well as ruminal kinetics, evaluated as passage rate of solid (3.09% hour -1 ) and liquid (4.37% hour -1 ) phases were similar for all treatments. Animal ingestive behavior measured as total time (minutes day -1 ) and rate (minutes DM kg -1 ) was not changed across silages DM concentration, averaging DM eating (324; 47), DM ruminating (518; 75) and DM chewing (841; 123), respectively. Residual daily time was spent with drinking and idling activities. The DM intakes observed among experimental diets, containing wilted silages, were not statistically different and averaged 6.95 kg day -1 or 1.88% as body weight basis. Individual and total (140.29) molar concentration (mM) of volatile fatty acids (VFA), acetate:propionate ratio (4,2:1), ammonia-N (6.31 mg dL -1 ) and average daily pH (6.76) of ruminal fluid were similar across silages diets. Nutrient digestibilities were, also, not significantly affected by the increased DM concentration in wilted silages or by the BE inoculation, as follows: organic matter (71.5%), crude protein (69.1%), NDF (71.3%), ADF (64.9%) and hemicellulose (83.3%). DM digestibilities, however, performed a quadratic pattern (P<0.05), with a slight increase at 45% DM concentration in silages. According to the results it may be concluded that neither the increase of DM concentration of grass silages nor the addition of bacterial-enzymatic inoculant changed animal ingestive behavior or improved ruminal and digestive parameters analyzed.

O presente trabalho teve como objetivo avaliar o efeito do emurchecimento da forragem associado ou não ao uso do aditivo bacteriano-enzimático na ensilagem do capim Tifton 85 (Cynodon spp.). Foi realizada avaliação de perdas nos painéis das silagens experimentais, assim como da composição bromatológica e do tamanho de partículas das mesmas. Ocorreram observações periódicas de comportamento ingestivo, consistência ruminal, consumo voluntário, parâmetros de fermentação ruminal, digestibilidade dos nutrientes, taxa de passagem de sólidos e líquidos ruminais em novilhos que receberam rações contendo 80% desses volumosos na base seca. Foram utilizados sete novilhos da raça Nelore, distribuídos ao acaso em um experimento do tipo quadrado latino 7 x 7. Os tratamentos avaliados foram resultantes da combinação de 3 concentrações de matéria seca (MS) na silagem do capim Tifton 85 (25, 45 e 65%) associadas (CA) ou não (SA) ao aditivo bacteriano-enzimático. Um tratamento adicional contendo 55% MS sem aditivo também foi avaliado. O aditivo utilizado foi o produto comercial SIL–ALL®, contendo cepas de Streptococcus faecium, Lactobacillus plantarum, Pediococcus acidilactici e as enzimas hemicelulase, celulase e amilase, aplicadas na dosagem de 250 g de SIL–ALL® diluídas em 50 litros de água por tonelada de forragem, imediatamente antes da ensilagem. A técnica de emurchecimento possibilitou elevar o teor de matéria seca mas, da mesma maneira que a adição do inoculante bacteriano-enzimático, provocou alterações pouco pronunciadas na composição química da silagem. Nas silagens SA o aumento da concentração de MS foi acompanhado de elevação no teor de FDN resultando em redução do teor de carboidratos não fibrosos (CNF). A fração protéica B3 nas silagens apresentou tendência de aumento com a elevação na concentração de MS, em função da progressiva elevação da fração N insolúvel no FDN, simultaneamente à redução N insolúvel no FDA. A avaliação dos silos após abertura, indicou aumento de perdas com a elevação da concentração de MS que, entretanto, podem ter sido decorrentes de uma menor taxa de utilização dos fardos contendo silagens com menor umidade. Tanto a consistência ruminal, avaliada como o tempo de ascensão do pêndulo no interior do rúmen (1194 seg.), como os parâmetros de cinética de passagem de sólidos (3,09% hora -1 ) e de líquidos (4,37% hora -1 ) foram similares para os tratamentos avaliados. O comportamento ingestivo dos animais não foi alterado com a elevação da concentração de MS da silagem, sendo observados tempos (minutos dia -1 ) e taxas (min kg MS –1 ) de ingestão de MS (324; 47), ruminação (518; 75) e mastigação (841; 123), respectivamente. O consumo diário de MS das rações, pelos animais, foi semelhante para os tratamentos avaliados, resultando em média de 6,95 kg equivalente a 1,88% do peso corpóreo. As concentrações molares (mM) individuais e totais (140,29) dos ácidos graxos voláteis, a relação acetato:propionato (4,2:1), concentração de nitrogênio amoniacal (6,31 mg dL -1 ) e o pH (6,76), do fluido ruminal, não foram alterados pelos tratamentos estudados. As digestibilidades da matéria orgânica (71,5%), proteína bruta (69,1%), FDN (71,3%), FDA (64,9%) e hemicelulose (83,3%) não foram, em geral, fortemente influenciadas pela concentração de MS da silagem do capim Tifton 85, aditivadas ou não. No entanto, a digestibilidade da MS (71,0%) apresentou um comportamento quadrático (P<0,05), com ligeira elevação ao redor de 45% de concentração de MS, nas silagens. Diante destas observações, pode-se concluir que o emurchecimento da forragem e o uso de aditivo bacteriano-enzimático não resultaram em alterações expressivas nos parâmetros ruminais, digestivos e no comportamento ingestivo dos animais. / The present trial aimed to study the effects of forage wilting associated or not with a bacterial-enzymatic inoculant on ensiling Tifton 85 grass. Front panel of experimental silos (325 kg square wrapped bales) were daily scored for fungi development and weekly sampled for chemical composition analysis and particle chop length measurements. In a randomized 7 x 7 Latin square design, seven ruminal cannulated growing beef steers were assigned to diets (treatments) containing 80% silage. Periodically chewing behavior, feed intake, ruminal mat consistency, ruminal fermentation parameters, nutrient digestibility and ruminal rate of passage of solids and liquids phases were evaluated. Treatments combined 3 planned dry matter (DM) concentrations (25, 45 and 65%) of Tifton 85 grass silage associated (CA) or not (SA) with the bacterial-enzymatic (BE) inoculant source. An additional treatment containing wilted silage (55% DM) without (BE) was also studied. SIL-ALL®, the BE source used, was sprayed onto chopped forage just before silage packing at a rate of 250g diluted in 50L of deionized water per ton of wet forage. The commercial BE showed the following composition: Streptococus faecium, Lactobacillus plantarum, Pediococcus acidilactici plus hemicellulase, cellulase and starch degrading enzymes. The wilting of forage allowed to increase the DM concentration of silages, however, as well as BE addition, it was not effective to promote major changes on chemical composition of silages. On SA silages, higher NDF levels were observed as the DM level of the wilted silage increased, which resulted in lower non-fiber carbohydrate (NFC) fraction. The B3 protein fraction (NDIN minus ADIN) showed an increase as the DM concentration of wilted silage was raised, probably as result of an opposite trend between neutral detergent insoluble nitrogen (NDIN) and acid detergent insoluble nitrogen (ADIN) across DM levels. Silage losses, measured as both, fungi scored at bale front panel and percentage of spoiled silage, indicated higher levels associated with increased DM concentration. It might be explained by the lower bale unloading rate observed during the feeding trial, mainly in higher DM wilted silages. Both, ruminal mat consistency, measured as time required to weight ascension into the rumen (1194 sec.) as well as ruminal kinetics, evaluated as passage rate of solid (3.09% hour -1 ) and liquid (4.37% hour -1 ) phases were similar for all treatments. Animal ingestive behavior measured as total time (minutes day -1 ) and rate (minutes DM kg -1 ) was not changed across silages DM concentration, averaging DM eating (324; 47), DM ruminating (518; 75) and DM chewing (841; 123), respectively. Residual daily time was spent with drinking and idling activities. The DM intakes observed among experimental diets, containing wilted silages, were not statistically different and averaged 6.95 kg day -1 or 1.88% as body weight basis. Individual and total (140.29) molar concentration (mM) of volatile fatty acids (VFA), acetate:propionate ratio (4,2:1), ammonia-N (6.31 mg dL -1 ) and average daily pH (6.76) of ruminal fluid were similar across silages diets. Nutrient digestibilities were, also, not significantly affected by the increased DM concentration in wilted silages or by the BE inoculation, as follows: organic matter (71.5%), crude protein (69.1%), NDF (71.3%), ADF (64.9%) and hemicellulose (83.3%). DM digestibilities, however, performed a quadratic pattern (P<0.05), with a slight increase at 45% DM concentration in silages. According to the results it may be concluded that neither the increase of DM concentration of grass silages nor the addition of bacterial-enzymatic inoculant changed animal ingestive behavior or improved ruminal and digestive parameters analyzed.

Made available in DSpace on 2016-04-28T14:59:45Z (GMT). No. of bitstreams: 1 2008 - Leandro Galzerano.pdf: 1398173 bytes, checksum: 3b9bc8540a1e5f744b54fffefe6a7828 (MD5) Previous issue date: 2008-08-05 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work was carried out in order to obtain subsidies under the definition of strategies for nitrogen fertilization of pastures of tifton 85, based on monitoring the dynamics changes in the structure of swards. The underlying assumption was that the application of increasing levels of N is a powerful tool for that purpose. The experiment was developed over a Planosol of occurrence in the experimental field of the Universidade Federal Rural Rio de Janeiro, city of Serop?dica, Brazil, during the establishment of the pasture, between the months of October, 2006 to January 2007. Treatments consisted of four levels of N (0, 50, 100 and 150 kg N-urea. ha-1), in single application, in plots of 4 x 4 m, arranged in blocks fully randomized, with four repetitions. Together with nitrogen fertilization, the plots received 80 kg P.ha-1 and 150 kg K.ha-1, and Ca as calcareo (1.0 tn.ha-1). The variables were: frequency of occurrence of plants; height of the canopy, leaf growth and leaf area index (LAI), the interception of photosynthetically active radiation (PAR) and the production and partition of dry matter. The results showed that the frequency of occurrence, height and interception of PAR varied according to a standard logistic, whose parameters have been modified to a greater or lesser degree, by the levels of N added. Similarly, at the 87 days after planting, the LAI and the total dry matter produced, but not its partition between leaves and stems, responded to changes in N mineral available in the soil. It was concluded that the application of increasing levels of Nurea, during the establishment of grass tifton 85 was an efficient experimental strategy for the induction of quantitative changes during the development time of swards structure. / O presente trabalho foi realizado com o prop?sito de definir estrat?gias de aduba??o nitrogenada em pastagens de tifton 85, baseadas no monitoramento de mudan?as din?micas na estrutura dos doss?is forrageiros. O experimento foi desenvolvido numa ?rea de Planossolo no campo experimental da Universidade Federal Rural do Rio de Janeiro, munic?pio de Serop?dica, RJ, durante a fase de estabelecimento da pastagem, entre os meses de outubro de 2006 a janeiro de 2007. Os tratamentos consistiram de quatro n?veis de N (0; 50; 100 e 150 kg N-ur?ia.ha-1), em aplica??o ?nica, dispostos em parcelas de 4 x 4 m, arranjadas em blocos inteiramente casualizados, com quatro repeti??es. Em conjunto com a aduba??o nitrogenada, as parcelas receberam 80 kg P.ha-1 e 150 kg K.ha-1. O solo foi corrigido com 1,0 tn.ha-1 de calc?reo. As vari?veis estudadas foram: freq??ncia de ocorr?ncia de plantas; altura do dossel, crescimento foliar e ?ndice de ?rea foliar (IAF), intercepta??o de radia??o fotossinteticamente ativa (RFA) e produ??o e parti??o da mat?ria seca. Os resultados obtidos mostraram que a freq??ncia de ocorr?ncia; altura e a intercepta??o de RFA variaram temporalmente de acordo com um padr?o log?stico, cujos par?metros foram modificados, em maior ou menor grau, pelos n?veis de N adicionados. De forma similar, aos 87 dias p?s- plantio, o IAF e a mat?ria seca total produzida, mas n?o a sua parti??o entre folhas e colmos, responderam ?s varia??es do N mineral dispon?vel no solo. Foi conclu?do que a aplica??o de n?veis crescentes de Nur?ia, durante a fase de estabelecimento do capim tifton 85 foi uma estrat?gia experimental eficiente para a indu??o de varia??es quantitativas durante o desenvolvimento temporal da estrutura dos doss?is.