L'ingénierie tissulaire est une discipline récente aux enjeux ambitieux et prometteurs : la régénération de tissus ou d'organes lésés voire détruits en mettant à profit des connaissances et compétences dans différents domaines à l'interface de la chimie et de la biologie. Pour répondre à la demande d'alternatives aux techniques chirurgicales actuelles de réparation du ligament antérieur croisé, nous avons décidé d'appliquer l'ingénierie tissulaire à ce tissu en associant matrices en polymères dégradables et cellules souches mésenchymateuses (CSM). Dans un premier temps, nous avons donc travaillé à la synthèse de polymères adaptés à l'application en cherchant à mettre l'accent sur l'obtention de propriétés élastiques. De nouveaux élastomères dégradables obtenus par des approches originales de photoréticulation chimique de poly(lactide) (PLA) et de poly(ε-caprolactone) (PCL) par voie nitrène ou thiol-yne ont notamment été développés avec des résultats prometteurs. En parallèle, des copolymères thermoplastiques multiblocs à base de PLA et poloxamine ou poloxamère nous ont permis de mener une étude plus appliquée. Ces copolymères ont en effet montré, en particulier au cours d'une étude de dégradation in vitro de 7 semaines, des propriétés, notamment thermiques et mécaniques, qui en font d'eux des candidats intéressants pour le conception d'une matrice ligamentaire. C'est pourquoi ils ont été utilisés pour la conception de prototypes de matrices de régénération textiles dont les propriétés mécaniques se sont révélées être très proches de celles du ligament. Après avoir démontré l'excellente cytocompatibilité de ces matrices avec des CSM, nous avons finalement mené des expériences de différenciation in vitro de ces CSM et sommes parvenus à favoriser leur orientation vers un phénotype ligamentocytaire, notamment grâce à un procédé de stimulation mécanique cyclique des cellules ensemencées sur les matrices textiles. / Tissue engineering is a recent discipline with ambitious and promising stakes: the regeneration of wounded or destroyed tissues or organs by taking advantage of knowledge and skills in various fields at the interface of chemistry and biology. In order to meet the need for alternatives to current surgical techniques of anterior cruciate ligament repair, we decided to apply the tissue engineering approach to this tissue by associating degradable polymer scaffolds and mesenchymal stem cells (MSCs). At first we worked on the synthesis of biodegradable polymers suitable for the application and focused on getting elastic properties. New degradable elastomers obtained by chemical photocrosslinking of poly(lactide) (PLA) and poly(ε-caprolactone) (PCL) were developed by following nitrene or thiol-yne strategies and yielded promising results. In parallel, a more in depth and practical study was performed with PLA based thermoplastic multiblock copolymers embedding poloxamer or poloxamine. These copolymers exhibited properties that make them attractive candidates for the design of ligament regeneration scaffolds, and especially their thermal and mechanical properties during a 7 week in vitro degradation test. That is why they were used to design prototypes of textile scaffolds whose mechanical properties were found to be very close to the ligament's ones. After demonstrating the excellent cytocompatibility of these scaffolds with MSCs, we finally carried out in vitro differentiation experiments on these MSCs and managed to induce their orientation towards a ligamentocyte phenotype, particularly through a process of cyclic mechanical stimulation of cells seeded on the textile scaffolds.

Na intenção de avaliar o efeito da suplementação protéica, uso de subprodutos agroindustriais e o processamento de milho, foram conduzidos quatro experimentos. No experimento I, avaliou-se formas de processamento de milho (milho moído, M; e resíduo de pipoca doce, P) e fontes protéicas (farelo de soja, FS; uréia, U; ou farinha de peixe, FP), combinando-os para formar quatro tratamentos: MFS (M + FS); PFS (P + FS); PFP (P + FS + FP); PU (P + U). Comparado ao milho moído (MFS), o resíduo de pipoca doce (PFS) diminuiu os teores de gordura e proteína no leite. Em relação às fontes protéicas (PFS x PFP x PU), observou-se que a maior produção leiteira foi obtida no tratamento PFS. A farinha de peixe (PFP) levou ao menor teor de gordura no leite, mas aumentou o teor protéico no leite. No experimento II, avaliou-se os efeitos da inclusão de três teores (0,15 e 30% da MS) de farelo de algodão (FA) em substituição ao farelo de soja na dieta. O consumo de MS não foi afetado pelos tratamentos, contudo a inclusão de FA levou a efeitos lineares negativos sobre a produção de leite e teor e produção de proteína e efeitos lineares positivos sobre o teor e produção de gordura no leite. No experimento III, comparou-se os efeitos de uma dieta basal com 16% de PB contra duas outras com 17,5% de PB, sendo esses incrementos obtidos através da adição de uréia (U-17,5, resultando em aumento de proteína degradável no rúmen, PDR) ou farelo de soja e de algodão (FSFA-17,5, resultando em aumento de proteína metabolizável, PM). O aumento do teor de PDR (U-17,5) tendeu a aumentar o consumo de MS em relação à dieta basal. A produção de leite elevou-se com o aumento de PM (FSFA-17,5), não ocorrendo o mesmo com o aumento de PDR (U-17,5). O teor e a produção de proteína no leite também elevou-se com o fornecimento extra de PM. Concluiu-se que a elevação do teor de PM para valores acima das recomendações propostas pelo National Research Council - NRC (2001) para vacas produzindo ao redor de 29 kg/d melhorou as produções de leite e de proteína no leite. O experimento IV consistiu de dois ensaios. No primeiro, os tratamentos continham 0 (RUC-0), 10 (RUC-10) ou 20% (RUC-20) de resíduo úmido de cervejaria (RUC). Todas as dietas continham 1% de uréia. Um quarto tratamento isoprotéico, com 2% de uréia substituindo parcialmente o farelo de soja, sem RUC, foi utilizado. O consumo de MS não foi afetado. A produção de leite e o teor e produção de proteína no leite aumentaram com a inclusão de RUC e foram prejudicados com o fornecimento de 2% de uréia. No ensaio 2, foram comparados o RUC fresco com o RUC ensilado com milho moído. Ambos os tratamentos eram isoprotéicos e continham proporções semelhantes de milho moído e RUC. O consumo de MS, produção de leite e os teores e produções de gordura e proteína no leite não foram afetados pelos tratamentos. / Four studies were conducted to compare protein sources and content, corn processing method and a fibrous by-product for lactating dairy cows. Study 1: corn processing methods (fine ground, M; and popped, P) and protein sources (soybean meal, FS; urea, U; or fishmeal, FP) were compared in 4 treatments: MFS (M + FS); PFS (P + FS); PFP (P + FS + FP); PU (P + U). Compared to fine ground corn (MFS), popped corn (PFS) decreased milk fat and protein content. The 3 protein sources comparisons (PFS x PFP x PU) showed that milk yield was higher for PFS. Feeding fishmeal (PFP) decreased milk fat content, but increased milk protein content. Study 2: the cottonseed meal content in the diet (0, 15 and 30% of DM) in replacement to soybean meal were compared. Dry matter intake was not affected by treatments, but cottonseed meal supplementation had a negative linear effect on milk yield and on milk protein content and yield. Increasing cottonseed meal had a positive linear effect on milk fat content and yield. Study3: basal diet (16% CP) was compared to two diets with 17.5% CP, where crude protein content of diets were increased by feeding extra urea (U-17.5, resulting in increased rumen degradable protein content, RDP) or extra soybean and cottonseed meal (FSFA-17.5, resulting in increased metabolizable protein content, MP). Extra RDP (U-17.5) tended to increase DMI compared to basal diet. Milk yield were increased by extra MP (FSFA-17.5) but not by extra RDP (U-17.5). Milk protein content and yield were also increased by feeding extra MP. In conclusion, increasing diet MP content above National Research Council - NRC (2001) recommendations for cows producing around 29 kg/d improved milk and milk protein yields. Study 4: two trials were conducted. In trial 1, treatments were 0 (RUC-0), 10 (RUC-10) or 20% (RUC-20) wet brewers grains inclusion in diet dry matter. All 3 diets contained 1% urea on a DM basis. A fourth isonitrogenous diet, with additional urea (2% of diet DM) in partial replacement of soybean meal, without brewers grains, was compared to. Dry matter intake were not different. Milk yields and milk protein contents and yields were increased by feeding wet brewers grains and decreased by feeding 2% urea. In trial 2, weekly received fresh wet brewers grains versus wet brewers grains ensiled with ground corn were compared. Both treatments were isonitrogenous diets and contained the same proportions of ground corn and wet brewers grains on a dry matter basis. Dry matter intake, milk yield, milk fat content and yield and protein content and yield were not different.

Percutaneous transluminal balloon angioplasty followed by drug-eluting stent implantation has been of great benefit in coronary applications, whereas in peripheral applications, success rates remain low. Analysis of healing patterns in successful deployments shows that six months after implantation the artery has reorganized itself to accommodate the increase in caliber and there is no purpose for the stent to remain, potentially provoking inflammation and foreign body reaction. Thus, a fully biodegradable polymeric stent that fulfills the mission and steps away is of great benefit. Biodegradable polymers have a widespread usage in the biomedical field, such as sutures, scaffolds and implants. Degradation refers to bond scission process that breaks polymeric chains down to oligomers and monomers. Extensive degradation leads to erosion, which is the process of mass loss from the polymer bulk. The prevailing mechanism of biodegradation of aliphatic polyesters (the main class of biodegradable polymers used in biomedical applications) is random scission by passive hydrolysis and results in molecular weight reduction and softening. In order to understand the applicability and efficacy of biodegradable polymers, a two pronged approach involving experiments and theory is necessary. A constitutive model involving degradation and its impact on mechanical properties was developed through an extension of a material which response depends on the history of the motion and on a scalar parameter reflecting the local extent of degradation and depreciates the mechanical properties. A rate equation describing the chain scission process confers characteristics of stress relaxation, creep and hysteresis to the material, arising due to the entropy-producing nature of degradation and markedly different from their viscoelastic counterparts. Several initial and boundary value problems such as inflation and extension of cylinders were solved and the impacts of the constitutive model analyzed. In vitro degradation of poly(L-lactic acid) fibers under tensile load was performed and degradation and reduction in mechanical properties was dependent on the mechanical environment. Mechanical testing of degraded fibers allowed the proper choice of constitutive model and its evolution. Analysis of real stent geometries was made possible with the constitutive model integration into finite element setting and stent deformation patterns in response to pressurization changed dramatically as degradation proceeded.

The prevention and treatment of cancer and infectious diseases requires vaccines that can mediate cytotoxic T lymphocyte-based immunity. A promising strategy is protein subunit vaccines composed of purified protein antigens and immunostimulatory adjuvants, such as Toll-like receptor (TLR) agonists. In this research, we developed two new biodegradable polymeric delivery vehicles for protein antigens and TLR agonists, as model vaccine delivery systems. This work was guided by the central hypothesis that an effective vaccine delivery system would have stimulus-responsive degradation and release, biodegradability into excretable non-acidic degradation products, and the ability to incorporate various TLR-inducing adjuvants. The first vaccine delivery system is a cross-linked polyion complex micelle which efficiently encapsulates proteins, DNA, and RNA. The micelle-based delivery system consists of a block copolymer of poly(ethylene glycol) (PEG) and poly(L-lysine), cross-linked by dithiopyridyl side groups to provide transport stability and intracellular release. The second delivery system consists of solid biodegradable microparticles encapsulating proteins, nucleic acids, and hydrophobic compounds. The microparticles are composed of pH-sensitive polyketals, which are a new family of hydrophobic, linear polymers containing backbone ketal linkages. Polyketals are synthesized via a new polymerization method based on the acetal exchange reaction and degrade into non-acidic, excretable degradation products. In addition, the technique of hydrophobic ion pairing was utilized to enhance the encapsulation of ovalbumin, DNA, and RNA in polyketal microparticles via a single emulsion method. Using in vitro and in vivo immunological models, we demonstrated that the micelle- and polyketal-based vaccine delivery systems enhanced the cross-priming of cytotoxic T lymphocytes. The model vaccines were composed of ovalbumin antigen and various TLR-inducing adjuvants including CpG-DNA, monophosphoryl lipid A, and dsRNA. The results demonstrate that the cross-linked micelles and polyketal microparticles have considerable potential as delivery systems for protein-based vaccines.

Made available in DSpace on 2015-03-26T14:02:14Z (GMT). No. of bitstreams: 1 texto completo.pdf: 282982 bytes, checksum: 02ab6e3afc4b760df02b71b3ecefbab5 (MD5) Previous issue date: 2009-05-29 / Pasture is the main source of cattle feed, but it is not capable of supplying the animal nutritional requirements completely. Therefore, an adequate management is necessary to improve productivity and reduce costs related to long term production. The search for technology to increase animal performance may be a feasible alternative to reduce costs with cattle nutrition. Fiber digesting ruminal bacteria utilize ammonia as their main source of nitrogen. Also, they have specific requirements for amino acids and an optimum growth when ruminal pH is around 6.2 to 6.8. For that, maximization of fiber fermentation is essential to increase ruminant production on pasture. Results of several experiments have shown that the supplementation of branched-chain amino acids (BCAA) increases feed intake, celluloses digestion, ruminal microbial growth, and daily gain for growing beef cattle. In this revision, studies show raise in milk production and daily gain in ruminants fed with forage based diets with the combination of some or all BCAA. In addition, this work makes possible to conclude that the supplementation with BCAA in association with rumen undegradable protein sources can increase animal production through the maximization of metabolizable protein. / O pasto constitui a principal fonte de alimentos dos bovinos, mas não é capaz de suprir todas as exigências nutricionais dos animais. Portanto, um manejo adequado é necessário para melhorar a produtividade e reduzir os custos associados à produção em longo prazo. A busca por tecnologias para o aumento do desempenho destes animais pode ser uma alternativa viável para reduzir os custos com alimentação do rebanho. Bactérias que fermentam carboidratos fibrosos (CF) utilizam a amônia como principal fonte de nitrogênio, possuem requerimentos específicos para aminoácidos e possuem um crescimento ótimo quando o pH ruminal está ao redor de 6,2 a 6,8. A maximização da fermentação de fibra é essencial para se aumentar a produção de ruminantes a pasto. Os resultados de vários experimentos têm mostrado que a adição de aminoácidos essenciais de cadeia ramificada aumenta a ingestão alimentar, a digestão da celulose, o crescimento dos microrganismos ruminais e o ganho de peso para animais em crescimento. Nesta revisão bibliográfica, os estudos mostram o aumento na produção de leite e no ganho de peso com a combinação de alguns, ou de todos os ácidos graxos voláteis de cadeia ramificada (AGVR) na dieta de ruminantes, compostas basicamente por volumosos. Além disso, através deste trabalho, conclui-se que é possível proporcionar um incremento na produção animal através da maximização da proteína metabolizável, associando AGVR a fontes de proteína não degradáveis no rúmen.

Submitted by DARIANE PRISCILA FRANCO DE OLIVEIRA null (dariane_franco@hotmail.com) on 2017-02-03T15:54:34Z No. of bitstreams: 1 dissertação Final 06 12 16.pdf: 2380104 bytes, checksum: 63e7cbfca21f56abc25ffd11110fd125 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-02-07T11:45:52Z (GMT) No. of bitstreams: 1 oliveira_dpf_me_bot.pdf: 2380104 bytes, checksum: 63e7cbfca21f56abc25ffd11110fd125 (MD5) / Made available in DSpace on 2017-02-07T11:45:52Z (GMT). No. of bitstreams: 1 oliveira_dpf_me_bot.pdf: 2380104 bytes, checksum: 63e7cbfca21f56abc25ffd11110fd125 (MD5) Previous issue date: 2016-09-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Tão elementar quanto produzir mudas de qualidade para o campo, é produzi-las de forma eficiente e ambientalmente correta. Com o surgimento de novas tecnologias no setor de produção de mudas é possível evitar recipientes de polietileno derivados do petróleo substituindo-os por materiais degradáveis, aliados ao uso racional da água. O objetivo deste trabalho foi avaliar a viabilidade técnica e econômica de mudas de Eucalyptus grandis x E. urophylla (E. urograndis) produzidas em recipiente degradável em comparação ao recipiente de polietileno sob três manejos hídricos. O enraizamento das estacas do híbrido E. urograndis em ambos os recipientes foi realizado no viveiro da empresa Eucatex, município de Bofete – SP. Em seguida, as mudas foram conduzidas ao viveiro do Departamento de Ciência Florestal da Faculdade de Ciências Agronômicas de Botucatu – SP, onde os manejos hídricos foram aplicados. Posteriormente, as mudas foram plantadas na área experimental da empresa Eucatex, município de Itatinga – SP. A pesquisa constituiu-se de dois experimentos, variando somente o ciclo de produção, sendo estes de 60 e 90 dias. Durante a fase de viveiro o delineamento foi inteiramente ao acaso e na de campo o delineamento foi de blocos casualizados. Os experimentos ocorreram em esquema fatorial 3x2 referentes a dois tipos de recipientes (degradável e polietileno) e três lâminas diárias de água (10, 12 e 14 mm). A análise do desenvolvimento das mudas foi composta de avaliações morfológicas (altura da parte aérea, diâmetro de colo, massa seca radicular, massa seca aérea, massa seca total e área foliar), e fisiológicas (transpiração). A análise econômica contemplou os custos de produção, ponderando todos os insumos utilizados, custo de capital, depreciação da infraestrutura e dos equipamentos utilizados e o ciclo de produção. No campo foram feitas quatro medições mensais de altura e diâmetro e medições fisiológicas após 10 meses de plantio. Os dados foram submetidos à análise de variância e nos casos em que houve diferença significativa foi realizado o teste de Tukey (p < 0,05). No ciclo de 60 dias, as mudas produzidas em ambos os recipientes apresentaram valores de diâmetro e altura satisfatórios para o plantio. Considerando o ciclo de 60 dias, a lâmina de 10 mm foi a mais adequada para ambos os recipientes. Para o ciclo de 90 dias, a lâmina de 10 mm foi mais adequada para as mudas do recipiente degradável e a lâmina de 12 mm para as mudas do recipiente de polietileno. O desenvolvimento no campo das plantas produzidas em ambas as embalagens mostrou-se satisfatório. Segundo as análises de investimentos, a produção de mudas de Eucaluyptus urograndis não se mostrou viável economicamente em nenhum dos sistemas de produção. / So elementary as produce appropriate seedlings to field, it is produce them efficiently and environmentally correct. The emergence of new technologies in seedling production sector can avoid polyethylene containers oil derivatives replacing them with degradable materials, associated with the appropriate and rational use of water. The purpose of this study was to assess the technical and economic viability of the degradable container (Ellepot®) comparing it with the polyethylene container, in the production of seedlings of the species Eucalyptus grandis seedlings x E. urophylla (E. urograndis), under three water management. The rooting of the stakes hybrid E. urograndis in both containers was conducted at Eucatex company’s nursery, in Bofete – SP. Then, the seedlings were taken to the nursery of the Department of Forest Science in the Faculty of Agricultural Sciences in Botucatu - SP, where water managements were applied. Thereafter, the seedlings were planted in the experimental area of Eucatex in Itatinga - SP. The research consisted of two experiments, varying only the production cycle, which are 60 and 90 days. During the nursery stage, the design was completely at random and in the field the design was randomized block. The experiments were set up in a 2x3 factorial, corresponding to two containers (polyethylene and degradable), and three daily irrigation blades (10, 12 and 14 mm). Technical analysis consisted of morphological and physiological evaluations and initial development of seedlings in field. The economic analysis included production costs, considering all the inputs used, capital cost, depreciation of the infrastructure and of the equipment used and the production cycle. The data were subjected to analysis of variance, and where significant differences existed, a Tukey test was performed (p < 0.05). In the cycle of 60 days, the seedlings produced, in both containers presented, diameter and height values suitable for planting. In this cycle, the blade 10 mm was optimal for both containers. In the cycle of 90 days, the blade 10 mm was most suitable for the seedlings of the degradable container and 12mm blade to the seedlings of the polyethylene container. The development in field of plants produced in both containers was satisfactory. According to the investment analysis, the production Eucaluyptus urograndis seedlings was not economically viable in any of the production systems.

L'objectif de ce projet repose sur le développement d’un dispositif médical intra-utérin résorbable prévenant l’apparition ou la récidive d'adhérences intra-utérines (synéchies). La mise en place de ce dispositif suite à chaque agréssion endométriale représenterait un bénéfice symptômatique et économique dans la prise en charge de l’infertilité par trouble de l'implantation. Ce dispositif repose sur l'association originale de polymères résorbables mis sous forme de films stérilisés et maléables, répondants aux contraintes spécifiques de la voie endo-utérine. Des tests sur culture cellulaire ont permis de valider son potentiel anti-adhérentiel en retrouvant des résultats comparables à ceux d’agents barrières disponibles sur le marché. La dégradation in vitro et in vivo du polymère a été étudiée afin de valider un délai d’efficacité suffisant. Des travaux expérimentaux ont été conduits après accord des comités d’éthiques. D’une part, des tests de reproduction animale ont été menés afin de démontrer l’innocuité du dispositif et son efficacité sur la fertilité. D’autre part, des travaux ont permis de valider sur le plan histologique l’effet préventif sur les synéchies. Un travail de modélisation a permis d’adapter la forme du film pour la voie utérine. Les tests de déploiement ont été conduits sur des utérus de cadavre et sur des pièces d’hystérectomie. Après mise en place aisée par les voies naturelles, le dispositif se déploie et gonfle afin de recouvrir la cavité utérine. Des travaux précliniques pourraient être envisagés avant un développement industriel afin d’améliorer les outils disponibles pour la prévention des synéchies intra-utérines. / The objective of this study was to develop an resorbable intra-uterine medical device preventing the appearance or the recurrence of intra-uterine adhesions (synechiaes). The insertion of the device following each endometrial injury would represent a symptomatic and economic benefit in the treatment of infertility by implantation failure. This device is base on the unique combination of resorbables polymers formed into sterilized and malleable films, respondents to the specific constraints of the endo-uterine way. Cellular assays allowed validating the anti-adhesive effect with results comparable to those of currents agents available for the clinical practice. The in vitro and in vivo degradation of the polymer was study to validate a sufficient period of efficiency. The use of experimental models allowed an evaluation of the polymer. On one hand, tests of animal reproduction were lead to demonstrate the harmlessness of the device and the efficiency on the fertility. On the other hand, work has validated histologically preventive effect on synechiaes. Finally, a modeling work allowed adapting the form and dimension of the film for the human uterine way. Tests of deployment carried out on fresh uterus from hysterectomy. After the insertion by the cervical way, the device unfolds and inflates to cover the uterine cavity. Preclinical studies could be done before an industrial development in order to improve the available tools for the clinical prevention of the intra-uterine synechiaes.

La réduction de l’impact des activités humaines sur l’environnement est au sujet de nombreux programmes de recherche. Ainsi, dans le domaine du transport aérien a été créé le projet Clean-Sky, regroupant les thèmes de recherche associés. La thèse, partie de ce dernier, a pour objectif de réduire l’impact environnemental de la production de composants en alliages avancés à base de Titane. La production actuelle ayant une empreinte écologique non négligeable, un procédé de fabrication alternatif est étudié, il s’agit du moulage par injection de poudres métalliques. La première partie de cette consiste donc en la recherche d’une formulation de mélange optimale parmi les solutions classiques et innovantes. Elles sont triées en fonction de leurs aptitudes, déterminées par caractérisations physico-chimiques, à assurer le bon déroulement de chaque étape du procédé. Un nombre réduit de solution étant ainsi dégagé, il s’agit de passer aux étapes d’injection, de déliantage et de frittage. Plusieurs géométries de pièces sont testées dans chacun de ces cas, afin de valider l’adaptation aux différentes contraintes imposées. Lors de ces trois phases, des analyses physico-chimiques complètes permettent de mettre en avant la ou les formulations les plus aptes à permettre la production de ces composants. Une fois la solution fixée, chaque étape du procédé est optimisées, afin de faciliter le transfert industriel et d’assurer la rentabilité du nouveau processus de fabrication. Ces travaux de doctorat ont permis de mettre en avant deux formulations, répondant aux critères définis en début de thèse. Les étapes de mélange, injection, déliantage et frittage ont été optimisées et le transfert industriel est possible. / Reducing the ecological footprint of human activities is, today, the aim of most of the research programs. In Europe, the « Clean Sky » project funds research activities to make air transport « greener ». This PhD, being part of it, is about improving production of Titanium Aluminide based components. Nowadays production having a strong environmental impact, an alternative way has been investigated: metal injection molding. The first step of this work was focused on a bibliographic study, to select relevant, common and innovative mixtures to be used in the process. Throughout the process, these mixtures have been tested, physically and chemically analyzed, to get data about the optimal mixture. Several components geometries have been tested, during injection, debinding, and sintering steps. Once the mixture(s) chosen, process’ parameters have been optimized to make industrial transfer easier, and lower its overall cost. The developments achieved during this PhD led to two qualified mixtures, and optimized mixing, molding, debinding and sintering steps.

Na intenção de avaliar o efeito da suplementação protéica, uso de subprodutos agroindustriais e o processamento de milho, foram conduzidos quatro experimentos. No experimento I, avaliou-se formas de processamento de milho (milho moído, M; e resíduo de pipoca doce, P) e fontes protéicas (farelo de soja, FS; uréia, U; ou farinha de peixe, FP), combinando-os para formar quatro tratamentos: MFS (M + FS); PFS (P + FS); PFP (P + FS + FP); PU (P + U). Comparado ao milho moído (MFS), o resíduo de pipoca doce (PFS) diminuiu os teores de gordura e proteína no leite. Em relação às fontes protéicas (PFS x PFP x PU), observou-se que a maior produção leiteira foi obtida no tratamento PFS. A farinha de peixe (PFP) levou ao menor teor de gordura no leite, mas aumentou o teor protéico no leite. No experimento II, avaliou-se os efeitos da inclusão de três teores (0,15 e 30% da MS) de farelo de algodão (FA) em substituição ao farelo de soja na dieta. O consumo de MS não foi afetado pelos tratamentos, contudo a inclusão de FA levou a efeitos lineares negativos sobre a produção de leite e teor e produção de proteína e efeitos lineares positivos sobre o teor e produção de gordura no leite. No experimento III, comparou-se os efeitos de uma dieta basal com 16% de PB contra duas outras com 17,5% de PB, sendo esses incrementos obtidos através da adição de uréia (U-17,5, resultando em aumento de proteína degradável no rúmen, PDR) ou farelo de soja e de algodão (FSFA-17,5, resultando em aumento de proteína metabolizável, PM). O aumento do teor de PDR (U-17,5) tendeu a aumentar o consumo de MS em relação à dieta basal. A produção de leite elevou-se com o aumento de PM (FSFA-17,5), não ocorrendo o mesmo com o aumento de PDR (U-17,5). O teor e a produção de proteína no leite também elevou-se com o fornecimento extra de PM. Concluiu-se que a elevação do teor de PM para valores acima das recomendações propostas pelo National Research Council - NRC (2001) para vacas produzindo ao redor de 29 kg/d melhorou as produções de leite e de proteína no leite. O experimento IV consistiu de dois ensaios. No primeiro, os tratamentos continham 0 (RUC-0), 10 (RUC-10) ou 20% (RUC-20) de resíduo úmido de cervejaria (RUC). Todas as dietas continham 1% de uréia. Um quarto tratamento isoprotéico, com 2% de uréia substituindo parcialmente o farelo de soja, sem RUC, foi utilizado. O consumo de MS não foi afetado. A produção de leite e o teor e produção de proteína no leite aumentaram com a inclusão de RUC e foram prejudicados com o fornecimento de 2% de uréia. No ensaio 2, foram comparados o RUC fresco com o RUC ensilado com milho moído. Ambos os tratamentos eram isoprotéicos e continham proporções semelhantes de milho moído e RUC. O consumo de MS, produção de leite e os teores e produções de gordura e proteína no leite não foram afetados pelos tratamentos. / Four studies were conducted to compare protein sources and content, corn processing method and a fibrous by-product for lactating dairy cows. Study 1: corn processing methods (fine ground, M; and popped, P) and protein sources (soybean meal, FS; urea, U; or fishmeal, FP) were compared in 4 treatments: MFS (M + FS); PFS (P + FS); PFP (P + FS + FP); PU (P + U). Compared to fine ground corn (MFS), popped corn (PFS) decreased milk fat and protein content. The 3 protein sources comparisons (PFS x PFP x PU) showed that milk yield was higher for PFS. Feeding fishmeal (PFP) decreased milk fat content, but increased milk protein content. Study 2: the cottonseed meal content in the diet (0, 15 and 30% of DM) in replacement to soybean meal were compared. Dry matter intake was not affected by treatments, but cottonseed meal supplementation had a negative linear effect on milk yield and on milk protein content and yield. Increasing cottonseed meal had a positive linear effect on milk fat content and yield. Study3: basal diet (16% CP) was compared to two diets with 17.5% CP, where crude protein content of diets were increased by feeding extra urea (U-17.5, resulting in increased rumen degradable protein content, RDP) or extra soybean and cottonseed meal (FSFA-17.5, resulting in increased metabolizable protein content, MP). Extra RDP (U-17.5) tended to increase DMI compared to basal diet. Milk yield were increased by extra MP (FSFA-17.5) but not by extra RDP (U-17.5). Milk protein content and yield were also increased by feeding extra MP. In conclusion, increasing diet MP content above National Research Council - NRC (2001) recommendations for cows producing around 29 kg/d improved milk and milk protein yields. Study 4: two trials were conducted. In trial 1, treatments were 0 (RUC-0), 10 (RUC-10) or 20% (RUC-20) wet brewers grains inclusion in diet dry matter. All 3 diets contained 1% urea on a DM basis. A fourth isonitrogenous diet, with additional urea (2% of diet DM) in partial replacement of soybean meal, without brewers grains, was compared to. Dry matter intake were not different. Milk yields and milk protein contents and yields were increased by feeding wet brewers grains and decreased by feeding 2% urea. In trial 2, weekly received fresh wet brewers grains versus wet brewers grains ensiled with ground corn were compared. Both treatments were isonitrogenous diets and contained the same proportions of ground corn and wet brewers grains on a dry matter basis. Dry matter intake, milk yield, milk fat content and yield and protein content and yield were not different.

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