Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES

Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul, FAPERGS

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-05-09T15:08:16Z No. of bitstreams: 1 Monica Alixandrina da Silva.pdf: 199800 bytes, checksum: b0b81ee8c6e462fbe0e41ca269e8f203 (MD5) / Made available in DSpace on 2017-05-09T15:08:16Z (GMT). No. of bitstreams: 1 Monica Alixandrina da Silva.pdf: 199800 bytes, checksum: b0b81ee8c6e462fbe0e41ca269e8f203 (MD5) Previous issue date: 2007-02-12 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The experiment was carried out at the IPA Experimental Station, Itambé-PE. The objectiv was to evaluate the direct and indirect relationship between the explanatory variables and the total dry matter yield and the leaf blade dry matter yield using a trail analysis approach. In addition to that, it was evaluated the nutritive value and dry matter production of five Pennisetum clones (IRI-381, HV 241, Venezuela, Elefante B and Hexaplóide) under cut, in the Forest Zone of Pernambuco. The experiment was accomplished in an exclusion area located in a grazed plot, divided in 6 paddocks. The paddocks were subdivided in five areas of approximately 833 m2. Each subdivision was occupied by a genotype of Pennisetum, and the exclusion area of each subdivision corresponded to 24 m2 (4 x 6 m). The design was complete randomized blocks, with six replications. The experimental period begun with a staging cut at ground level (17/08/2005) followed by evaluation cuts every 60 days thereafter. The evaluations were accomplished inside a square of 1 m2, within an utile area of 2 m2. For the study of the effect of the variables in the trail analysis, it was considered as main dependent variables the total dry matter production (PMST) and leaf blade dry matterproduction (PMSLF), in t/ha. As explanatory independent variables, the following variables were used: average plant height (AP), number of sheets/tiller (NFP), number of basal tillers/m2 (NP), tiller mass, in kg (PP), stem diameter (DC) and relationship leaf blade/stem(RFC). The stem diameter did not present significant correlations with total dry matter yield and leaf blade dry matter yield; therefore, it was withdrawn from the trail analysis study. The following response variables were determined: dry matter concentration (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), mineral matter (MM), in vitro dry matter digestibility (IVDMD), total carbohydrates (TC),and non-fibrous carbohydrates (NFC). Just the ADF and TC concentrations in the leaf blade differed among the evaluated clones. The other parameters presented medium heritability,inferring genetic variability. The variables presented positive correlations of medium to highmagnitude; however, the number of basal tillers and the relationship leaf blade/stem presented negative Pearson correlation with all the other variables, except between themselves. The stem diameter did not present significant correlation with the productive variables, being excluded of the trail analysis. The plant height presented high correlation with the production of total dry matter (0,911), however, the increase in the total dry matter yield was better explained by the stem mass. Regarding the leaf blade dry matter yield, the leaf blade mass presented the highest correlation with that dependent variable (0,711), but the number of leaf blade/tiller explained better the increase on the leaf blade dry matter yield. The leaf blade and stem dry matter yields didn't present significant differences, with productivity of 1.7 t of DM/ha and 2.1 t of DM/ha, respectively. The leaf blade nutritive value presented significant and high heritability for ADF and TC, indicating that there were genetic differences among the appraised clones. This fact did not happen with the stem nutritive value which did not show significant differences among treatments for the evaluated response variables, presenting medium to high heritability. Considering these results, we concluded that the stem mass presented nutritive value similar to the leaf blade,indicating that for these clones, it is possible the use at 60 days of regrowth. The stem mass and the number of leaf blade/tiller explained better the increase on the dry matter production. / O experimento foi realizado na Estação Experimental de Itambé-PE, objetivando avaliar através da análise de trilha, a relação direta e indireta existente entre as variáveis explicativas e a produção de matéria seca total e de lâminas foliares, bem como estimar valor nutritivo e produção de matéria seca de cinco clones de Penisetum (IRI-381, HV 241, Venezuela, Elefante B e Hexaplóide) sob corte. O experimento foi realizado em uma área de exclusão mantida numa área de panstagem. A área de exclusão correspondeu a 24 m2 (4 x 6 m) para cada clone avaliado. O delineamento foi blocos casualizados, com 6 repetições. O período experimental foi iniciado com um corte de uniformização rente ao solo (17/08/2005), e a cada 60 dias. Para o estudo do efeito das variáveis na análise de trilha, foram consideradas como variáveis dependentes principais, à produção de matéria seca total (PMST) e produção de matéria seca de lâminas foliares (PMSLF), em t/ha. Como variáveis independentes explicativas, utilizaram-se as seguintes variáveis: altura média das plantas (AP), número de lâminas foliares/perfilho (NFP), número de perfilhos basais/m2 (NP), peso de perfilho, em kg (PP), diâmetro dos colmos (DC) e relação lâmina foliar/colmo (RFC). O diâmetro do colmo, por não ter apresentado correlação significativa com a produção de matéria seca total e de lâminas foliares, foi retirado do estudo da análise de trilha. Determinou-se a composição química e a digestibilidade dos clones avaliados. As variáveis apresentaram correlações positivas e de média a alta magnitude, entre si, entretanto, o número de perfilhos basais e a relação lâmina foliar/colmo foram as variáveis que apresentaram correlação de Pearson negativa com todas as demais variáveis, exceto entre si. A altura da planta apresentou alta correlação com a produção de matéria seca total (0,911), porém, a variável independente que explicou diretamente o aumento da produção de matéria seca total foi o peso do colmo. Em relação a produção de matéria seca de lâminas foliares apesar do peso das lâminas foliares ter apresentado a mais alta correlação com essa variável dependente (0,711), o número de lâminas foliares/perfilho explicou o aumento da produçãode matéria seca de lâminas foliares. Em relação à produção de matéria seca de lâminas foliares e colmos, os tratamentos não apresentaram significância, com produções de 1,7 t de MS/ha e 2,1 t de MS/ha, respectivamente. Apenas os teores de FDA e CT nas lâminas foliares apresentaram diferenças significativas. Os demais teores apresentaram herdabilidade média, inferindo variabilidade genética. O valor nutritivo de lâminas foliares apresentou significância e alta herdabilidade para o FDA e CT, indicando que houve diferenças genéticas entre os clones avaliados. O que não ocorreu com o valor nutritivo dos colmos que não apresentaram significância entre os tratamentos para todas as variáveis, apresentando média a alta herdabilidade. Considerando os resultados obtidos, conclui-se que o peso do colmo apresentou teores semelhantes às lâminas foliares, indicando que para os clones estudados, é possível a utilização de capineira aos 60 dias de idade. O peso do colmo e o número de lâminas foliares/perfilho foram as variáveis que melhor explicam o aumento da produção.

Kikuyu (Pennisetum clandestinum) is highly productive during summer and autumn and capable of supporting high cattle stocking rates., The winter and spring production of kikuyu, however, is low, while forage quality, and consequently milk production per cow, is also low compared to temperate grass species. The aim of this study was to determine the dry matter yield, botanical composition, nutritional value, grazing capacity and milk production potential of irrigated kikuyu over-sown with Italian ryegrass (Lolium multiflorum var. italicum), Westerwolds ryegrass (Lolium multiflorum var. westerwoldicum) or perennial ryegrass (Lolium perenne) under an intensive grazing system with Jersey cows. Calibrations for the rising plate meter (RPM) were developed for the kikuyu-ryegrass systems. These calibrations were evaluated for seasonal variation, linearity and were also combined over seasons, treatments and years to develop a calibration equation that could be used by dairy farmers in the region. The three kikuyu based pasture systems reached their peak growth rates during different months and seasons. All treatments experienced lower growth rates during winter, while peak growth rates occurred during spring for the Italian ryegrass treatment; summer for the Westerwolds ryegrass treatment and late spring/early summer for the perennial ryegrass treatment. All three treatments had similar total annual dry matter yields (kg DM ha-1) during the first year of the study. However, during year 2 the PR treatment had a higher annual DM production than IR and WR treatments. The ability of the PR treatment to maintain DM production during periods when the other treatments underwent a dip in production (WR during spring and IR during summer) enabled the PR treatment to maintain a higher annual DM production during year 2 than the systems based on annual ryegrass species. As the kikuyu component increased in kikuyu-ryegrass pastures from winter to summer, the DM and NDF content increased, while the ME content decreased. All three treatments were deficient in Ca throughout the study and deficient in P during summer and autumn for high producing dairy cows. The Ca:P ratio was below the recommended ratio of 1.6:1 for high producing dairy cows throughout the study. The grazing capacity of all three kikuyu-ryegrass systems was lower during winter and autumn than during spring and summer. The seasonal grazing capacity of the perennial ryegrass treatment, however, was more evenly distributed than that of the Italian and Westerwolds ryegrass treatments. The perennial ryegrass treatment had a lower butterfat and milk production per lactation than the Italian and Westerwolds ryegrass treatments during both years, but had the highest milk production per ha. The latter was a result of the higher annual grazing capacity achieved by the perennial ryegrass treatment. It was thus concluded that, because kikuyu over-sown with perennial ryegrass supported a higher number of animals and had a more evenly distributed fodder-flow, it allowed for higher animal production per ha than kikuyu over-sown with annual ryegrass varieties such as Italian and Westerwolds ryegrass. The pre-grazing and post-grazing regressions of all three the kikuyu based pastures developed for the RPM differed over seasons and years, primarily due to the change in botanical composition from ryegrass based pastures during winter to kikuyu-based pastures in the summer and the associated change in pasture structure. The post-grazing regressions developed during the study did not have a lower degree of accuracy (R2 values) than the pre-grazing regressions. The generalised RPM regression equations developed for kikuyu-ryegrass pastures (consisting of large data sets pooled over treatments and years) could be of use to farmers in the surrounding area, but are not recommended for research purposes due to the large errors and variation associated with such regressions. In the event that farmers employ these calibrations it is important that pasture type and pasture management practices be similar to those utilised during the study. The decision on which kikuyu-ryegrass system to utilize should be based on the specific conditions prevalent on a particular farm, an economic analysis on and a comparison between the three systems, as well as the particular fodder-flow program requirements within the pasture system. / Dissertation (MSc(Agric))--University of Pretoria, 2010. / Plant Production and Soil Science / unrestricted

Dentre as estruturas que compõem os fitômeros das gramíneas, a folha tem grande importância, pois é a fonte primária de produção de fotoassimilados para a planta como um todo e também é o componente de maior valor nutritivo. Em gramíneas, o alongamento de folhas e, consequentemente da nervura central, ocorre de forma não proporcional, afetando a morfologia e a anatomia das lâminas foliares e interferindo em seu valor nutritivo. Com o intuito de avaliar a relação entre tamanho final do limbo foliar, proporção e espessura da nervura central (NC) e sua relação com as características anatômicas e o valor nutritivo (VN) em lâminas foliares de diferentes tamanhos e ordens de inserção, foram conduzidos dois experimentos concomitantes utilizando um protocolo de plantas isoladas desenvolvido especificamente para esta finalidade no verão de 2017 (janeiro a março). A espécie estudada foi o Pennisetum purpureum Schum. cv. Napier (capim-elefante). O objetivo do primeiro experimento foi caracterizar o padrão de expansão e a morfologia da lâmina foliar seccionada em 10 fragmentos de mesmo tamanho, e caracterizar a anatomia ao longo dos segmentos basal, mediano-basal, mediano, mediano-apical e apical, ambos em lâminas foliares de perfilhos basais de diferentes tamanhos e ordens de inserção (fitômeros 5 a 16) em função de sua programação ontogênica. As coletas de amostras tiveram início a partir da expansão da 5ª folha (fitômero 5) e foram encerradas quando a 16ª folha completou sua expansão (fitômero 16). Para avaliar o efeito da idade da folha sobre a deposição de tecidos de sustentação, foram coletadas todas as folhas de dois perfilhos (um para avaliações anatômicas e um para avaliações morfológicas) no momento da expansão da 16ª folha, seguindo os mesmos critérios de avaliação descritos anteriormente. As plantas foram distribuídas segundo um delineamento em blocos completos casualizados com quatro repetições. O objetivo do segundo experimento foi caracterizar a relação entre o padrão de expansão das folhas (proporção de nervura central) e seu valor nutritivo ao longo dos segmentos de folhas descritos acima, nas mesmas folhas. A amostragem foi realizada quando a 16ª folha concluiu seu desenvolvimento e expôs sua lígula. Foram cultivadas 1320 plantas, divididas em três blocos homogêneos com 440 plantas cada, de modo a proporcionar a quantidade mínima necessária de material seco e moído para análises de proteína bruta (PB) e digestibilidade in vitro da matéria seca (DIVMS). As lâminas foliares apresentaram o mesmo padrão de expansão, apesar de diferentes valores de largura e comprimento final. A massa de nervura central variou linearmente com o aumento de massa da lâmina foliar, e apresentou redução em sua proporção da base para a porção apical da folha. Não houve variações significativas nas características anatômicas entre os segmentos das lâminas foliares quando a nervura central não foi considerada. Excluindo os segmentos em processo de senescência (fitômeros 5 a 7), as porções finais de folhas grandes apresentaram valor nutritivo semelhante àquele de folhas pequenas. As análises multivariadas de agrupamento (Cluster) e de componentes principais (PCA) agruparam e classificaram as folhas de acordo com seu nível de inserção no perfilho e aporte estrutural. As folhas mais longas foram caracterizadas como segue: 1- frações basais por altos valores de esclerênquima (ESC), massa seca da nervura (MSN), largura da nervura (LN) e mesofilo (MES) e baixos valores PB, área foliar específica (AFE), DIVMS e epiderme total (EpiT); 2- frações medianas com altos valores de feixes vasculares (FV), comprimento da folha (CF), comprimento do segmento (CS), massa seca do limbo (MSL), massa seca total (MST), largura do limbo (LL) e largura total (LT) e baixos valores de matéria mineral (MM); e 3- frações apicais (próximas ao ápice foliar) com altos valores de PB, AFE, DIVMS e EpiT e baixos valores de ESC, MSN, LN e MES. As folhas mais curtas, independentemente de suas porções ou segmentos, se caracterizaram por altos valores de DIVMS, MM, PB, EpiT e AFE e baixos valores de FV, ESC, MES, MSN, CF, CS. Os resultados podem ser utilizados para desenvolver modelos de crescimento tridimensional das plantas com a capacidade de predizer valor nutritivo e ingestão de nutrientes de animais em pastejo, bem como auxiliar no estabelecimento de metas de manejo do pastejo. / Among the structures comprising grass phytomers, the leaf is important because it is the primary source of assimilate for the entire plant and is also the component of greatest nutritive value. In grasses, leaf elongation, and consequently mid rib elongation, occurs in a non proportional way, affecting the morphology and the anatomy of the leaf blade and impacting its nutritive value. This study aimed at evaluating the relationship between final leaf blade length and the proportion and thickness of the mid rib, as well as their relation with anatomical characteristics and nutritive value along the blades of leaves with different sizes and levels of insertion on the tiller (leaf age - phytomers 5 to 16). Two concomitant experiments were carried out during summer of 2017 (January to April) using an isolated plant protocol specifically developed for this purpose. Elephantgrass (Pennisetum purpureum Schum. cv. Napier) was used as model plant. The objective of the first experiment was to characterize the pattern of leaf expansion and the morphology and anatomy of the leaf blade in sections along its length (basal, median-basal, median, median-apical, apical) using leaves of different sizes and levels of insertion (phytomers 5 to 16) on basal tillers according to their ontogenetic organization. Sampling started when the fifth leaf (phytomer 5) completed its expansion and ended when the 16th leaf (phytomer 16) completed its expansion. In order to evaluate the effect of leaf age on the synthesis of support tissues, all leaves from two tillers (one for anatomical and other for morphological evaluations) were harvested when the 16th leaf completed its expansion, following the same procedures described above for individual leaves. The experimental design was a randomized complete block, with four replications. The objective of the second experiment was to characterize the relationship between the pattern of leaf expansion (proportion of mid rib in leaf blade) and nutritive value along the length (basal, median-basal, median, median-apical, apical portions) using leaves of different sizes and levels of insertion (phytomers 5 to 16) on basal tillers. Sampling was done when the 16th leaf completed its expansion and exposed its ligule. A total of 1,320 plants were cultivated in three homogeneous blocks of 440 plants each, ensuring the minimum amount of dry, ground material for the chemical analyses of crude protein (CP) and in vitro dry matter digestibility (IVDMD). There was a common pattern of leaf expansion despite the different final leaf blade width and length. The weight of mid rib varied linearly in relation to the increase in leaf blade mass, and showed a decreasing gradient of proportion from the basal to the apical portion of the leaf. Anatomically, there were no significant changes in tissue proportions along the length of the leaf blade when the mid rib was not considered. Except for the senescing apical portion of older leaves (phytomers 5 - 7), the apical portion of large leaves showed similar nutritive value (IVDMD and CP) to that of small leaves. The multivariate analyses of Cluster and Principal Components grouped and stratified phytomers according to their level of insertion on the tiller and structural support, with longer leaves characterized as: 1- basal portions with high values of sclerenchyma (SCL), mid rib mass (MRM), mid rib width (MRW) and mesophyll (MES) and low values of CP, specific leaf area (SLA), IVDMD and total epidermis (EPIt); 2- median portions with high values of vascular bundles (VB), leaf blade length (LBL), portion length (PL), non-mid rib leaf blade mass (LBM), total leaf blade mass (TLBM), non mid rib leaf blade width (LBW) and total leaf blade width (TLBW) and low values of mineral matter (MM); and 3- apical portion with high values of CP, SLA, IVDMD and EPIt and low values of SCL, MRM, MRW and MES. Shorter leaves were characterized by high values of IVDMD, MM, CP, EPIt and SLA and low values of VB, SCL, MES, MRM, LBL and PL. The results can be used for developing tridimensional plant growth models capable to estimate the nutritive value and nutrient intake by grazing animals, as well as to assist in establishing grazing management targets.

En Afrique subsaharienne, une large partie de la population pratique l’agriculture pluviale. Cette agriculture est particulièrement sensible à la variabilité climatique. Le mil (Pennisetum glaucum L Br) est une des céréales pluviales qui jouent un rôle majeur dans la sécurité alimentaire en Afrique subsaharienne. L’apparenté sauvage du mil cultivé pousse dans des environnements encore plus extrêmes que la forme cultivée. L’objectif de la thèse est l’étude de l’adaptation du mil à la variation environnementale. En utilisant des approches d’association génotype /phénotype, nous avons démontré que le gène de la myosine 11 est associé à la variation du nombre de fleurs chez le mil sauvage observée le long d’un gradient environnemental. En plus, ce gène a également été identifié dans les candidats pour les gènes sélectionnés durant la domestication. En utilisant des données génomiques, nous avons aussi démontré que le gène du Photochrome C déjà connu pour son rôle dans le contrôle de la variation du temps de floraison chez le mil cultivé, est aussi associé à la variation du temps de floraison chez le mil sauvage. Nous avons aussi démontré l'existence d'un polymorphisme fonctionnel cryptique (caché) qui n’apparaît que dans certaines conditions particulières associées au temps de floraison. Ce polymorphisme cryptique peut être mobilisé dans des conditions climatiques ou environnementales particulières. Chez le mil cultivé, nous avons aussi pu mettre en évidence la sélection in situ sur deux gènes de floraison. Nos résultats suggèrent que de nombreux polymorphismes associés à l’adaptation sont présents dans les populations et peuvent être partagés entre forme sauvage et cultivée. En réponse aux changements environnementaux, ces polymorphismes pourraient être mobilisés pour proposer des variétés mieux adaptées. / In sub-Saharan Africa, a large fraction of the population practice rainfed agriculture. Rainfed agriculture is particularly sensitive to climate variability. Pearl millet (Pennisetum glaucum L R) is one of the main cereals that play an important role in food security in sub-Saharan Africa. Wild pearl millet populations grow also in more extreme climate conditions up to the limit of the desert. The aim of this PhD was to study pearl millet adaptation to climate variation. Using an association genotype / phenotype approach, we demonstrated that the myosin 11 gene is associated with flower number variation in wild millet along an environmental gradient. Interestingly, this gene was also a candidate gene target of selection during domestication. The Myosin XI gene is thus a good candidate for fitness related adaptation in wild populations. We also demonstrated that Photochrome C gene, already known for its role in cultivated pearl millet, is also related to flowering time variation in wild pearl millet. We have demonstrated the existence of cryptic functional polymorphisms associated with flowering time. Such cryptic functional polymorphism might contribute to adaptation in specific new environment. In cultivated pearl millet, we also show in situ selection on two flowering genes. Our results suggest that the functional polymorphisms are observed in these populations, some genes are also associated with both adaptations in wild and cultivated populations. In response to environmental changes, such polymorphism could be used to propose better adapted cultivated varieties.

Les céréales sont des aliments de base dans la plupart des pays africains. De nombreux aliments céréaliers africains sont fermentés naturellement. Comme la qualité nutritionnelle des aliments céréaliers pourrait être améliorée grâce aux fermentations spontanées, ces aliments pourraient être de bonnes sources de micronutriments. Cependant, différentes carences en micronutriments, comme les carences en folates par exemple, sont toujours fréquentes dans de nombreux pays africains où ces aliments sont consommés. Les carences en folates peuvent mener à différentes pathologies, comme des anémies mégaloblastiques et des malformations du tube neural par exemple. L’objectif de ce travail était d’évaluer le potentiel nutritionnel du microbiote du ben-saalga, un aliment fermenté traditionnel à base de mil consommé au Burkina Faso. Des gènes codant des enzymes impliquées dans différentes activités nutritionnelles ont été recherchés dans 50 métagénomes extraits d’échantillons collectés à Ouagadougou. Certains gènes n’ont jamais été détectés dans les métagénomes (e.g. les gènes impliqués dans la synthèse de caroténoides), alors que d’autres ont été fréquemment détectés (e.g. les gènes impliqués dans la synthèse de folates). En dépit du haut niveau de détection (80%) des deux gènes folP et folK, codant des enzymes impliquées dans la synthèse de folates, la teneur en folates du ben-saalga était plutôt faible (médiane : 0,5 µg/100g de base humide). Pour mieux comprendre l’impact de la fermentation sur la teneur en folates du ben-saalga, l’évolution de la teneur en folates a été mesurée durant la fermentation de bouillies produites en laboratoire. La fermentation n’a pas eu d’impact significatif sur la teneur en folates, ce qui pourrait être dû à une balance entre les micro-organismes auxotrophes et les micro-organismes prototrophes pour les folates. Dans le but de produire des bouillies fermentées à base de mil avec des teneurs en folates plus élevées, des cultures starters de micro-organismes producteurs de folates ont été utilisés pour inoculer des bouillies au laboratoire. Nous avons obtenu une bouillie avec une teneur en folates de 10 µg/100g de base humide, ce qui est significativement plus élevé que la teneur en folates du ben-saalga produit au Burkina Faso, mais qui reste trop faible sachant que le ben-saalga est fréquemment utilisé comme un aliment de complément à l’allaitement maternel pour les enfants de moins de cinq ans. / Cereals are staple foods in most African countries. Numerous African cereal-based foods are spontaneously fermented. As the nutritional quality of cereal products could be enhanced through spontaneous fermentation, these food products might be good sources of micronutrients. However, various micronutrients deficiencies, such as folate deficiency, are still common in many African countries where these food products are consumed. Folate deficiency leads to different pathologies, such as megaloblastic anemia and neural tube defects. The objective of this work was to evaluate the nutritional potential of the microbiota of ben-saalga, a traditional pearl-millet-based fermented food from Burkina Faso. Genes encoding enzymes involved in different nutritional activities were screened in 50 metagenomes extracted from samples collected in Ouagadougou. Certain genes were never detected in the metagenomes (e.g. genes involved in carotenoid synthesis) while other were frequently detected (e.g. genes involved in folate synthesis). In spite of the high rate of detection (80%) of both genes folP and folK, encoding enzymes involved in folate synthesis, the folate content in ben-saalga was rather low (median: 0.5 µg/100g fresh weight basis). To better understand the impact of the fermentation on the folate content of ben-saalga, the evolution of the folate content was measured during the fermentation of porridges produced in laboratory. The fermentation had no significant impact on the folate content, which may be due to a balance between folate auxotrophy and prototrophy. In order to produce pearl-millet based fermented porridges with higher folate content, starter cultures of folate-producing microorganisms were used to inoculate porridges in laboratory. We obtained a porridge with 10 µg of folate/100 g of fresh weight basis, which is significantly higher than the folate content of ben-saalga produced in Burkina Faso, but still too low knowing that ben-saalga is frequently used as a complementary food for children under five in Burkina Faso.

Made available in DSpace on 2014-06-11T19:28:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-08-06Bitstream added on 2014-06-13T20:37:11Z : No. of bitstreams: 1 tamele_oh_me_jabo.pdf: 845403 bytes, checksum: d8970fb9ee11f562e24d468628d0f786 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os experimentos foram conduzidos na Faculdade de Ciências Agrárias e Veterinária, (FCAV) – Universidade Estadual Paulista, (UNESP) Campus de Jaboticabal, nos anos de 2007 e 2008. No primeiro ano de avaliação foram estudadas duas alturas de pré - pastejo (0,60 e 0,80 m) e duas alturas de pós – pastejo (0,10 e 0,20 m) para híbridos de sorgo em sistema de pastejo com vacas; numa área de 3056 m² subdividida em 12 parcelas, o delineamento experimental utilizado foi delineamento em blocos casualizados com três repetições o período experimental foi de maio a novembro de 2007. O 2º ano o experimento foi realizado numa área de 2650, 36 m² subdividido em 24 parcelas com o objetivo de avaliar a produção de massa seca total dos híbridos de sorgo e cultivares de milheto e estudar o comportamento ingestivo dos ovinos nos híbridos de sorgo e cultivares de milheto em resposta aos espaçamentos de 0,225 e 0,45 m. o período experimental foi de abril a outubro de 2008. Conforme os resultados experimentais sugerem-se para o primeiro experimento a utilização do manejo de 0,60 m altura de entrada e 0,10 m altura de saída dos animais nos piquetes já que proporciona mesma quantidade de massa e o mesmo número dos ciclos de pastejo quando comparado ao manejo 0,80m/0,10m. No segundo experimento os híbridos de sorgo e cultivares de milheto podem ser indicados para pastejo de ovinos e o espaçamento de 0,225 m poderia ser adotado para o manejo dos cultivares de milheto e híbridos de sorgo com as ovelhas já que proporcionou maior produção de massa seca total e maior número de perfilhos reprodutivos quando comparada com o espaçamento de semeadura de 0,45 m / Two experiments were conducted on the Faculdade de Ciências Agrárias e Veterinárias, (FCAV) - Universidade Estadual Paulista (UNESP) Campus de Jaboticabal, in 2007 and 2008, with the objective of: 1 st year - to evaluate the viability of using sorghum hybrid by rotative Holstein cows grazing with two height of pre-grazing (0.60 and 0.80 m) and two post-grazing residues (0.10 and 0.20 m) in an area of 3,056 m² divided into 12 plots. The experimental design was DBC with three replications and the experimental period was from May to November 2007. The 2nd year the experiment was conducted in an area of 2650, 36 m² divided into 24 plots to evaluate the total dry mass of hybrids Sudan sorghum and millet cultivars and evaluate the ingestive behavior of sheep in that forages with spacing of 0.225 and 0.45 m of plants. The experimental period was from April to October of 2008. The experimental results suggest for the first experiment using the management of 0.60 m height for pre-grazing and postgrazing at 0.10 m of height to animals in paddocks thus there were the same amount of total dry mass and the same number of cycles of grazing management when compared to 0,80 m / 0,10 m. In the second experiment the spacing of 0.225 m could be used for management of millet cultivars and sorghum hybrids with the sheep where it was provided a great the total dry mass and number of reproductive tillers compared with the spacing of sowing of 0.45 m

Made available in DSpace on 2015-03-26T13:54:39Z (GMT). No. of bitstreams: 1 texto completo.pdf: 259784 bytes, checksum: bf02d9afe7c4df31111cb741ce4d8305 (MD5) Previous issue date: 2008-02-22 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Two experiments were conducted, on a completely randomized design, to evaluate the nutritive value, fermentative characteristics and losses of elephant grass silage produced with and without wilting and added of cassava meal (0; 7,5; 15 e 22,5 % da MN), and to determine protein and carbohydrate fractions of silage. It were used PVC silos with 50 cm height and 10 cm diameter, fitted with a Bunsen type valve to eliminate gas produced by fermentation and sand placed in the bottom to capture effluents. In experiment I, wilting associated with cassava meal was efficient to increase dry matter (DM) content, minimize DM losses and reduce crude protein (CP), acid detergent insoluble nitrogen, neutral detergent fiber, neutral detergent fiber ash and protein free, acid detergent fiber, and celluloses contents. Cassava meal addition in elephant grass silage production caused reduction in ether extract, hemicelluloses and lignin contents and increased organic matter content, in vitro DM digestibility, and total digestible nutrients. The wilting treatment had effect only in neutral detergent insoluble nitrogen content. Relative to variables inherent to silages fermentative characteristics, pH and butyric acid presented quadratic behavior, with pH showing minimum value of 3.7 % in 15.9 % cassava meal level, in no wilting silages, value within the range considered satisfactory to obtain silage of quality. Concerning to ammonia nitrogen and acetic acid, it was observed quadratic and decreasing linear behavior for silages without and with wilting, respectively. In regard to propionic acid, it was verified a decreasing linear behavior in silages without wilting and, in wilted silages there was no effect on this variable. There was wilting and cassava meal levels effect only on silages lactic acid value, which reduced linearly. Wilting and cassava meal can be used to increase silage DM content. In experiment II, the fractions that compose total carbohydrates (TC) and CP of the silages were determined and evaluated. The regression analysis detected a linear rising of TC content as function of cassava meal addition. The association of wilting with different levels of cassava meal influenced the TC fractions (A+B1 and B2), but had no effect on nitrogen fractions (A and B1+B2). Cassava meal addition reduced linearly the TC C fraction. Silages fractions B3 and C presented significant interaction between wilting and cassava meal levels, verifying quadratic effect of B3 fraction content and decreasing linear effect of C fraction. / Dois experimentos foram conduzidos, no delineamento inteiramente casualizado, para avaliar o valor nutritivo, as características fermentativas e as perdas da silagem de capim-elefante produzida com e sem emurchecimento e acrescida de farelo de mandioca nos níveis 0; 7,5; 15 e 22,5 % da (MN) e determinar as frações protéicas e dos carboidratos da silagem. Foram utilizados silos de PVC com 50 cm de altura e 10 cm de diâmetro, providos de válvula de Bunsen, para saída de gases oriundos da fermentação, e areia no fundo, para captação dos efluentes. No experimento I, a associação do emurchecimento com o farelo de mandioca elevou os teores de matéria seca (MS), minimizou as perdas de MS e reduziu os teores de proteína bruta (PB), nitrogênio insolúvel em detergente ácido, fibra em detergente neutro, fibra em detergente neutro isenta de cinzas e proteína, fibra em detergente ácido e celulose. A adição de farelo de mandioca na produção da silagem de capim-elefante reduziu os teores de extrato etéreo, hemicelulose e lignina e aumentou o teor de matéria orgânica, a digestibilidade in vitro da MS e os nutrientes digestíveis totais. O emurchecimento teve efeito apenas sobre os teores de nitrogênio insolúvel em detergente neutro. Em relação às variáveis inerentes às características fermentativas das silagens, o pH e o ácido butírico apresentaram comportamento quadrático, o pH apresentou valor mínimo de 3,7 % no nível de 15,9 % de farelo de mandioca, nas silagens não emurchecidas, valor dentro da faixa considerada satisfatória para obtenção de silagem de qualidade. Quanto ao nitrogênio amoniacal e ácido acético, observou-se comportamento quadrático e linear decrescente para as silagens sem e com emurchecimento, respectivamente. No tocante ao ácido propiônico, verificou-se comportamento linear decrescente nas silagens sem emurchecimento e, nas silagens emurchecidas, não se constatou efeito sobre esta variável. Houve efeito de emurchecimento e de níveis de farelo de mandioca apenas sobre o valor de ácido lático das silagens, que reduziu linearmente. O emurchecimento, bem como o farelo de mandioca podem ser utilizados para elevar os teores de MS da silagem. No experimento II, foram determinadas e avaliadas as frações que constituem os carboidratos totais (CHO) e a PB das silagens. A análise de regressão detectou elevação linear do teor de CHO em função da adição de farelo de mandioca. A associação do emurchecimento com os diferentes níveis de farelo de mandioca influenciaram as frações de CHO (A+B1 e B2), mas não tiveram efeito sobre as frações nitrogenadas (A, B1+B2). A adição de farelo de mandioca reduziu linearmente a fração C dos CHO. No que concerne às frações B3 e C das silagens, observa-se que as mesmas apresentaram interação significativa entre emurchecimento e níveis de farelo de mandioca, constatando-se efeito quadrático para os teores da fração B3 e efeito linear decrescente para a fração C.

Made available in DSpace on 2016-12-08T16:24:20Z (GMT). No. of bitstreams: 1 PGCA14MA150.pdf: 671118 bytes, checksum: 044e392b9e087c5b498a3cdbdfdf9d62 (MD5) Previous issue date: 2014-09-19 / The sustainable management of pastures is in evidence in academic circles, looking for a better association between animal performance and natural resources conservation. The aim of this work was to evaluate cattle pattern displament on kikuiu-grass submitted to different heights and the same level of defoliation of 50%. The experiment was carried out at CAV/UDESC during April and May 2013. The experimental design was a complete randomized block design with three replications and four treatments. The treatments were four pre-grazing heights: 25, 20, 15 and 10 centimeters associated which were associated with a level of defoliation of 50%. Animals stand longer on feeding stations in 20 and 25 cm swards during the initial stage of grazing without differences on the final phase of grazings down. At the early stage, on the lower pasture height (10 cm) the animals walked more and moved more quickly when compared to those managed at higher swards heights (5,25 e 4,0, respectively). There was no difference during the final stage of grazings process. The bite number in each feeding station had a linear reduction with the increase in sward height during the initial phase, being minor on the 25 cm height (27 bites.feeding station-1), with no differences at the final stage. Bite rate (bites. min-1) also presented a linear response by reducing according the increase in pasture height, from 42,02 to 35,18 bites.min-1 in pastures with 10 and 25 cm, respectively. During the initial phase of the grazing down the animals presented diferences in displacement patterns, suggesting that swards heights of 20 to 25 cm (in kikuygrass) present better conditions to foraging search. At the final phase, the animals did not present differences among treatments, suggesting that on using 50% of the grazing down is already over the limit when the objective is to minimize forage searching / O manejo sustentável das pastagens está ganhando cada vez mais espaço na pesquisa mundial, visando maior desempenho animal aliado à preservação dos recursos naturais. O objetivo deste trabalho foi avaliar os padrões de deslocamento de bovinos em pastos de capim-quicuio, submetidos a diferentes alturas de entrada e mesma severidade de desfolhação de 50%. O experimento foi realizado no setor de bovinocultura leiteira do CAV/UDESC, durante os meses de abril e maio de 2013. O delineamento experimental foi em blocos completos casualizados com três repetições e quatro tratamentos. Os tratamentos eram quatro alturas em pré-pastejo: 25, 20, 15 e 10 cm, associados com uma severidade de desfolhação de 50% destas alturas. O maior tempo de permanência dos animais nas estações alimentares foi encontrado nos pastos mais altos, com 20 e 25 cm de altura, na fase inicial de rebaixamento dos pastos, sem diferenças na fase final do rebaixamento. Os animais caminharam mais (P.min-1) e com maior rapidez (passos entre estações) nos pastos mais baixos (10 cm), durante a fase inicial de rebaixamento destes. Já na fase final não foram observadas alterações. O número de bocados em cada estação alimentar na fase inicial do rebaixamento apresentou uma redução linear com o aumento da altura, sendo menor na altura de 25 cm (27,02), permanecendo sem diferenças na fase final. A taxa de bocados (bocados. min-1) também apresentou uma resposta linear, reduzindo conforme o aumento na altura dos pastos, de 42,02 para 35,18 bocados.min-1, nos pastos com 10 e 25cm, respectivamente. Os animais na fase inicial de rebaixamento dos pastos apresentaram diferenças nos padrões de deslocamento, indicando que alturas de dossel de 20 e 25 cm (em pastos de capim-quicuiu) apresentam melhores condições ao processo de forrageamento. Já na fase final, os animais não apresentaram diferenças entre os tratamentos, sugerindo que utilizando a faixa de 50% de rebaixamento dos pastos os animais já encontram dificuldades no processo de busca por forragem, independente de metas de alturas em pré-pastejo