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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Réaction de nitration en continu pour la synthèse d’un principe actif pharmaceutique : fonctionnalisation d’hétérocycles borés obtenus par borylation électrophile / Continuous nitration reaction for the synthesis of an active pharmaceutical ingredient : functionnalisation of boron heterocycles synthetised by electrophilic borylation

Charbonnier, Jean-Baptiste 08 June 2018 (has links)
La fluidique est un outil offrant des avantages industriels notamment en termes de sécurité grâce à un meilleur contrôle thermique mais aussi une diminution des risques due à un engagement de volumes faibles. Cette technologie permet des réactions chimiques plus efficaces grâce à un système plus homogène qui impacte les rendements, la sélectivité ou encore la quantité de réactifs nécessaire. Aujourd’hui, la production de principes actifs pharmaceutiques est réalisée majoritairement en procédé batch. Ainsi, dans une première partie, la microfluidique a été appliquée à la synthèse d’un principe actif pharmaceutique. Les diverses étapes réactionnelles ainsi que les paramètres physiques du système ont été optimisés avec l’utilisation de micromélangeurs. Un procédé multi-étapes a été développé avec une productivité atteignant 100 g.h-1. Des productions ont été réalisées validant les tests préliminaires ainsi que la possibilité de production du principe actif pharmaceutique en continu.Les dérivés du bore sont quant à eux des intermédiaires réactionnels couramment utilisés pour leurs réactivités en synthèse organique. Ainsi, dans une seconde partie, la réaction de borylation électrophile a été étudiée, et plus spécifiquement la synthèse des oxa et des azaborinines grâce au complexe diisopropylamine borane (DIPAB) utilisé comme agent de borylation. Ces dernières molécules ont ensuite été fonctionnalisées grâce à des réactions d’oxydation, d’amination ou d’halogénation. / Fluidic devices offer industrial advantages especially in terms of security due to a better thermal control and a minimization of risks with lower volumes involved. This technology increases chemical reaction efficiencies thanks to a more homogeneous system which affects yields, selectivity and reagent quantities. Nowadays, pharmaceutical active principles are still predominantly produced using batch. Thus, in a first part, microfluidic has been applied to the synthesis of an active pharmaceutical ingredient. Each reaction step as well as the physical parameters of the system have been optimized by using a micromixer. A multi-step process has been developed with a productivity up to 100 g.h-1. Productions have been realized thereby validating preliminary studies including the possibility to produce the active pharmaceutical ingredient.Boron derivatives are chemical intermediates commonly used in organic synthesis for their reactivity. In a second part, electrophilic borylation reaction has been studied with the synthesis of oxa and azaborinins compounds as targets and the use of diisopropylamine borane complex (DIPAB) as a borylation agent. These molecules have then been functionalized through the use of oxidation, amination or halogenation reactions.
62

Recursos e capacidades em situação de turnaround: um estudo de caso no negócio de alimentos

Silva, Carlos Vinnícius 05 November 2015 (has links)
Made available in DSpace on 2016-03-15T19:26:29Z (GMT). No. of bitstreams: 1 Carlos Vinniciusaa.pdf: 942384 bytes, checksum: b02c033a7fef53fd8b3ceaee31e18de5 (MD5) Previous issue date: 2015-11-05 / Universidade Presbiteriana Mackenzie / The aim of this dissertation has been to understand the resource and capabilities that proved to be strategic in the turnaround process, creating value to the company customer, from the Resource Based-View RBV perspective. The research method adopted to this single case study was the exploratory descriptive with qualitative approach, applying an standardized script of open questions. The content analysis technique has been used for the data treatment. Eight business executives were interviewed from sales, marketing, research and development, pricing and profitability and supply chain area, which were working in the company when the turnaround process happened. The company is one of the most important global supplier companies for the food ingredients market, operating in the business-to-business segment. The results have indicated that the resources, technical expertise and sales team specifically prepared, and the capabilities, mindset change and synergy between the internal areas, were considered strategic due to the fact that they supported the turnaround strategies, enabling the company to recover its profitability. It has been found that the debility of these resources might lead the food ingredient market suppliers, which operate in the business-to-business segment, to operate like in the commodity segment and to face substantial difficulties to survive in the market. In addition to have these resources, the company must have the capability to keep them in synergy and focused on customer needs, thereby it might acquire competitive advantage. / O objetivo desta dissertação foi entender os recursos e capacidades que se mostraram estratégicos no processo de turnaround visando à criação de valor para os clientes da empresa, sob a perspectiva da Visão Baseada em Recursos VBR. Foi adotado o método de pesquisa qualitativo de caráter exploratório descritivo para o estudo de um caso único, tendo sido empregado um roteiro padronizado de perguntas abertas. O tratamento dos dados se deu por técnica de análise de conteúdo. Foram entrevistados oito executivos da área de vendas, marketing, pesquisa e desenvolvimento, precificação e lucratividade e de cadeia de suprimentos que atuavam na empresa na época em que ocorreu o turnaround. A empresa é uma das principais multinacionais que opera globalmente no mercado de ingredientes para indústria de alimentos, atuando no segmento empresa-empresa. Os resultados indicaram que os recursos, conhecimento técnico e equipe comercial especificamente preparada, e as capacidades, mudança de mindset e sinergia entre as áreas, foram consideradas estratégicas por terem suportado as estratégias de turnaround, permitindo que a empresa do estudo recuperasse a lucratividade. Constatou-se que a debilidade desses recursos pode levar empresas de ingredientes para indústria de alimentos, que atuam no segmento empresa-empresa, a um processo de comotidização e consideráveis dificuldades de sobrevivência neste mercado. E que além de possuir esses recursos, a empresa precisa ter a capacidade de mantê-los em sinergia e focados nas necessidades do cliente para que possa obter vantagem competitiva.
63

Prescribing patterns of angiotensin-converting enzyme inhibitors for the period 2001 until 2006 / Lourens Johannes Rothmann

Rothmann, Lourens Johannes January 2007 (has links)
Thesis (M.Pharm. (Pharmacy Practice))---North-West University, Potchefstroom Campus, 2008.
64

Prescribing patterns of angiotensin-converting enzyme inhibitors for the period 2001 until 2006 / Lourens Johannes Rothmann

Rothmann, Lourens Johannes January 2007 (has links)
Thesis (M.Pharm. (Pharmacy Practice))---North-West University, Potchefstroom Campus, 2008.
65

Antinutritional factors in modeling plant-based rainbow trout diets

2014 February 1900 (has links)
The effect of inclusion rate of pea meal (PM), pea protein concentrate (PPC), soybean meal (SBM), soy protein concentrate (SPC), canola meal (CM) and canola protein concentrate (CPC) in salmonid diets was determined through six corresponding meta-analyses of all data available in the literature for these six feed ingredients, which was followed by weighted regression analysis. Increasing dietary inclusion levels of SBM, SPC, CM and CPC reduced specific growth rate (SGR). Regression analysis determined all of these relationships to be linear declines in SGR (P < 0.05). Inclusion levels of PM or PPC did not influence salmonid SGR (P > 0.05). These results showed that the influence plant proteins have on salmonid SGR is dependent on ingredient type and inclusion level. PM, PPC, SBM, SPC, CM an aqueous-extracted CPC and a high phytate CPC (PCPC) were analyzed for chemical nutrient (proximate, amino acid and phosphorus analysis) and antinutrient composition and total tract digestibility (two separate digestibility trials) in rainbow trout (Oncorhynchus mykiss). The digestibility of proximate chemical components and amino acids were significantly higher for the soy products than the pea products. These digestibilities were also significantly higher in protein concentrates than in plant meals. Dry matter and gross energy digestibility was higher in CPC than in CM (P < 0.05). Phosphorus digestibility was higher in CPC-fed fish than in CM-fed fish (P < 0.05), which is likely due to the fact that CPC did not contain phytic acid. Six consecutive growth studies (one trial per test ingredient) were conducted over a 361-day period to determine the effects of feeding increasing inclusion rates of PM, PPC, SBM, SPC, CM and CPC on the growth performance of rainbow trout. Diets were formulated based on the digestible nutrient content of all ingredients as determined in the previously conducted digestibility trials, to contain 0, 75, 150, 225 or 300 g/kg of each test ingredient. All diets were nutritionally equal and contained 17.6 MJ/kg digestible energy, 386.2 g/kg digestible crude protein and were balanced for digestible essential amino acids to meet or exceed the requirements of rainbow trout. Linear and quadratic analysis was conducted on the experimental data. There were no significant regressions resulting from feeding PM, SPC or CPC at 0-300 g/kg for average daily feed intake (ADFI), specific growth rate (SGR), feed conversion ratio (FCR) or protein efficiency ratio (PER). A positive relationship was associated between PPC inclusion and ADFI (P < 0.05). There was a significantly negative quadratic equation associated with the inclusion level of SBM on SGR and FCR and significantly negative linear and quadratic equations for PER. There were significantly negative linear relationships between the inclusion rate of CM and the SGR, FCR and PER of rainbow trout (P < 0.05). Growth trial results suggest at inclusion levels up to 300 g/kg, PM, PPC, SPC and CPC are feasible plant-based fish meal replacements with predictable growth effects, provided the nutritional constraints set in this experiment are followed. The results of these growth experiments were further analyzed using structural equation modeling to determine the relationship between ANF in the six ingredients and ADFI and SGR, which were transformed (tSGR and tADFI, respectively) to enable comparisons between experiments. All possible models between ingredient ANF (starch, phytic acid, glucosinolates, tannins, isoflavones, total NSP, soluble NSP, insoluble NSP and saponins) and ADFI and SGR were calculated. The model with the highest likelihood, as determined by the Akaike Information Criteria0, contained 29 parameters and six degrees of freedom. tADFI positively influenced tSGR. Glucosinolates, saponins, and phytates had a significantly negative impact on tADFI, whereas tannins had a significantly positive impact. The presence of saponins in the diet resulted in a decrease in tSGR. This structural equation model had significant correlations between all ANF, with the exception of phytates and saponins. Future applications of this work will be to develop a nutritional model for optimal inclusion of plant-based feed ingredients in rainbow trout diets, based on their ANF content, which may improve the accuracy of diet formulation and growth prediction.
66

Formulation de nanosystèmes et évaluation de leur potentiel pour la délivrance cutanée de molécules actives / Formulation of nanosystems and evaluation of their potential for delivery of active molecules to the skin

Nguyen, Hoang Truc Phuong 14 December 2015 (has links)
Ces travaux visent à déterminer l‘intérêt de deux types de nanosystèmes (NS) coeur-couronne dans des applications dermatologiques ou cosmétiques. Les nanocapsules lipidiques (LNC) sont obtenues par une méthode déjà décrite dans la littérature. Leur formule est modifiée pour incorporer un actif cosmétique d‘intérêt. Les nanocapsules d‘alginate (ANC) sont développées au moyen de plans d‘expériences. Elles sont composées d‘un coeur huileux et d‘une coque d‘alginate de calcium gélifiée obtenue par gélification ionique de surface d‘une nanoémulsion. Des méthodes basées sur le phénomène de fluorescence nous permettent de mettre en évidence l‘endocytose des ANC par les kératinocytes. Leur contenu est rapidement libéré dans le cytoplasme. Une étude sur différents modèles ex vivo montre que les deux nanosystèmes permettent aux molécules encapsulées d‘atteindre les couches vivantes de l‘épiderme. ANC et LNC sont stables plusieurs mois dispersées dans des formes galéniques semi-solides. Ces deux NS sont donc adaptés à la délivrance de molécules actives dans la peau. / Two types of core-shell nanosystems have been evaluated for dermatological and cosmetic applications. Lipid nanocapsules (LNC) are obtained by a method that has already been described in the literature. Their composition is adapted for incorporation of a specific cosmetic ingredient. Alginate nanocapsules (ANC) are developed with the aid of experimental design. They consist of a triglyceride core with a rigid calcium alginate shell obtained by ionic gelation of the surface of a nanoemulsion. By incorporating fluorophores into these nanosystems, they can be studied by advanced spectral fluorescence imaging methods. We were thus able to show that ANC are first internalized into keratinocytes by endocytosis, and once inside the cells, their contents are rapidly released into the cytoplasm. A study of different ex vivo skin model systems has shown that both nanosystems enable active substances to reach the living epidermis. When incorporated into gels similar to those used as galenic forms for topical administration, LNC and ANC remain stable for months. They can thus be used as vectors for delivering active substances to the skin.
67

Intensification of pharmaceutical production : from the raw materials to the crystallized active pharmaceutical ingredient / Intensification d'une production pharmaceutique : des matières premières au principe actif cristallisé

Conté, Jennifer 19 February 2016 (has links)
L’un des nombreux défis pour l’industrie pharmaceutique est de développer des procédés compétitifs pour produire des principes actifs de hautes qualités à bas coût. Pour ce faire, plusieurs sociétés se tournent vers la chimie en flux continu et les avantages qu’elle présente comparé au batch traditionnel. C’est pourquoi ces travaux de thèse se centrent sur le développement d’un procédé continu allant des matières premières au principe actif. La première étape pour parvenir à ce but fut de collecter des données sur le procédé batch industriel actuel. Il se compose de trois étapes de réactions chimiques, une de séparation chromatographique et une étape de cristallisation. A partir de là, la chimie de chaque réaction a été adaptée pour profiter au mieux des avantages du flux continu. La dissipation de chaleur étant plus efficace qu’en batch il fut possible de développer une réaction exothermique sans solvant à haute température. Une étude cinétique a été réalisée afin de modéliser cette réaction. Ensuite, cet outil fut utilisé pour déterminer les conditions opératoires optimales théoriques de la réaction et en guider l’optimisation ainsi que la conception du futur réacteur. La deuxième partie de ce travail se focalise sur la cristallisation en continu du principe actif avec la technique des jets impactant. Il est nécessaire d’avoir un contrôle précis sur la distribution de taille de particules (DTP) et la morphologie des cristaux. En effet, le principe actif peut cristalliser sous deux formes compétitives : cristaux cubiques ou en forme d’aiguilles. Les cubes sont la forme désirée. La technique des jets impactant a été sélectionnée car c’est un procédé continu qui permet la génération de fines particules avec une DTP resserrée. La sursaturation est généralement crée en impactant un jet de solution de principe actif avec un jet d’anti-solvant. Ici, le solvant et l’anti-solvant sont les mêmes. Seule une large différence de température entre les deux jets génère la sursaturation. En testant différentes conditions opératoires, une « zone cubique » a été définie, où seuls des cristaux de forme désirée sont générés. Une fois la nucléation maîtrisée, le murissement et la séparation solide-liquide furent étudiés pour développer un procédé complet de cristallisation. En combinant les recherches sur le développement des réactions chimiques et l’étape de cristallisation, un procédé continu complet fut proposé et comparé au procédé batch actuel afin d’évaluer les bénéfices apportés par la transposition en flux continu à la production du principe actif. / One of the many challenges in the pharmaceutical industry is to develop competitive processes to generate high quality active pharmaceutical ingredient (API) at low cost. To achieve this goal, many companies are looking towards flow chemistry and the advantages it affords, compared to traditional batch production. It is why this PhD work is focused on developing a continuous process from the raw materials to the API. The first step to achieve this goal was to collect data on the actual industrial batch process. It is composed of five steps, three steps of chemical reactions, one chromatographic separation and a crystallization step. From this starting point, the chemistry of each reaction was adapted to better use the advantages of flow chemistry. Thus, as the heat recovery in a continuous reactor is more efficient than in batch, it was possible to develop an exothermal reaction in neat conditions and at high temperature. A kinetic study was undertaken to gather knowledge on the reaction and develop a reaction model. This tool was used to find theoretical optimal operating conditions (temperature, residence time…) to guide the optimisation of the reaction and to design the future industrial reactor. The second part of this work is focused on the continuous crystallization of the API using the two impinging jets technology. It is required to have a tight control upon the morphology of the crystals and the particle size distribution (CSD). Indeed, the targeted API may crystallize under two competitive forms: cubic and needle crystals. The cubic form is the desired one. The two impinging jets technique was selected, since it is a continuous process able to generate small particles with a narrow CSD. The supersaturation is traditionally generated by impacting a jet of API solution with an anti-solvent one. Here, the solvent and the antisolvent are identical and only a large temperature difference between both streams is used to create the supersaturation. By screening different operating conditions, a “cubic zone” could be defined. Within this zone, only the desired crystal form is generated. Once the nucleation was under control, crystal growth and solid-liquid separation were studied to develop a complete crystallization process. By combining the research on the development of the chemical reactions and the crystallization step a full continuous process was proposed and was compared to the current batch one in order to evaluate the benefits brought by the flow chemistry to the API production.
68

Tribulations d'une jeunesse sans diplôme : de l'école aux dispositifs « seconde chance » / Trials and tribulations of a youth without diploma : from school to « second chance » programs

Vollet, Juliette 28 October 2016 (has links)
Face aux bouleversements économiques et sociaux qui ont affecté la société française depuis les années 70, le décrochage scolaire, c’est-à-dire la sortie du système de formation initiale sans avoir obtenu un diplôme de niveau V (BEP ou CAP) ou de niveau supérieur(baccalauréat), est appréhendé aujourd’hui comme un risque pour le bien-être individuel et collectif. Un large éventail de mesures a donc été déployé pour lutter contre le décrochage scolaire : des mesures préventives qui visent à prévenir les arrêts scolaires prématurés, et des mesures réparatrices dont l’objectif est de favoriser le « raccrochage », c'est-à-dire le retour des jeunes décrocheurs dans un parcours de formation.Sur un plan scientifique, les processus menant au décrochage scolaire sont désormais connus.En revanche, peu d’informations existent sur les processus de raccrochage. Prenant acte de cette lacune, cette thèse propose de tourner le regard vers ce qu’il se passe en aval du décrochage scolaire, en retraçant le parcours des « décrocheurs » qui « raccrochent », en observant le fonctionnement des dispositifs dits de « seconde chance » et en en questionnant les effets. Pour ce faire, on privilégie une approche séquentielle des trajectoires, en identifiant trois séquences clés du processus : la séquence de décrochage, la séquence de raccrochage et la séquence d’accrochage au dispositif. L’enjeu est d’éclairer les ingrédients qui provoquent le basculement d’une séquence à l’autre. On s’appuie pour cela sur 120 entretiens semidirectifs menés auprès de jeunes « décrocheurs » inscrits ou ayant été inscrits au sein de trois types de dispositifs de « remédiation » au décrochage : les Écoles de la deuxième chance qui visent le retour en formation ou l’entrée en emploi par des mises en stage fréquentes et une remise à niveau scolaire, les Établissement Publics d’Insertion à la Défense qui s’appuient sur un encadrement et des règles d’inspiration militaire pour favoriser l’obtention d’un emploi, et les microlycées ou structures innovantes de l’Éducation nationale qui préparent au baccalauréat.On observe d’une part que le temps est un ingrédient majeur du raccrochage, difficilement pris en compte par les dispositifs chargés de l’accompagnement des décrocheurs, et d’autre part que l’accrochage au dispositif de « remédiation » est indexé aux lectures que les jeunes font de leur situation présente, et qui engagent leur expérience scolaire passée, les contraintes de la formation et ses apports quotidiens ou supposés. On montre aussi que le raccrochage n’est pas le pendant événementiel du décrochage. L’action des dispositifs de remédiation est en effet contrainte par leurs environnements social et économique, de sorte qu’ils ne peuvent garantir à tous les jeunes qu’ils accueillent, une stabilisation de leurs situations sociale et personnelle. / Dropping out of school has been seen as a risk rather than for individual than for collective well-being given the economic and social up heavals of the French society since the 70’s. A lot of measures have been implemented to tackle the phenomenon whether preventive or repairing. The first ones aim to prevent the dropout and the others are meant to promote the « school reconnection », or in other words to encourage the dropouts to return to school. Processes leading to dropout are now well-known from a scientific perspective. By contrast, there is only limited information on processes leading to reconnect with education. With the objective to fill this gap, this PhD provides a focus on what happens for the dropouts after they leave school, redrawing their path to « school reconnection ». This study includes an observation of the functioning of the so-called « seconde chance » establishments and an analysis of their effects on their pupils. Through a sequential approach of those paths, we identified three key sequences: the dropout, the reconnection and the remaining sequence in which young people invest their reconnection training. I wanted to highlight the ingredients leading to a sequence to another. To do so, I lead 120 semi-structured interviews with young people who dropped out and are now or have been registered within 3 types of French remediation establishments : the « Écoles de la Deuxième chance », the « EPIDe»(Établissement Publics d’Insertion à la Défense), and the « SRE » (Structures de retour à l’école).To begin with, I noted that time is a key ingredient for school reconnection. Furthermore I noticed that the remaining sequence depends on how young people read their situation combining their past scholar experience, the reconnection program constraints and its contributions, effective or expected. Finally, I observed that remediation establishments rely on their social and economic environment, meaning that the « reconnection » can not be viewed as a counterpart of dropout.
69

Efeitos do glicerol no metabolismo de frangos de corte alimentados com dietas contendo níveis crescentes de glicerina / Effects of glycerol on the metabolism of broilers fed diets with increasing levels of glycerin

Gislaine Goretti Romano 31 January 2013 (has links)
Dois experimentos foram conduzidos com o objetivo de identificar a resposta metabólica dos animais consumindo dietas contendo glicerina e verificar o efeito deste ingrediente em alguns parâmetros sanguíneos. No Experimento I foram ultilizados 100 frangos de corte com 20 dias de idade, alojados em gaiolas de metabolismo, distribuídos em um delineamento inteiramente aleatorizado, com 5 tratamentos, 4 repetições e 5 aves por gaiola. Os tratamentos consistiram de uma dieta controle, formulada à base de milho e farelo de soja, e outras quatro dietas formuladas com 2,5%, 5,0%, 7,5% e 10,0% de glicerina de biodiesel. A glicerina continha 83,63% de glicerol, 1,83% de sódio e 397 mg/Kg de metanol e foi considerado o valor energético de 3.258 kcal EMAn/kg. As dietas foram isoenergéticas e com valores ajustados dos demais nutrientes. Para os parâmetros sanguíneos (colesterol e triglicerídeos), concentração de glicerol no fígado e peso do fígado não houve efeito significativo (P>0,05) da inclusão de glicerina. A concentração de glicerol no soro das aves consumindo 10% de glicerina aumentou nos primeiros 9 dias de ingestão da dieta (P<0,05), retornando ao nível do controle. No Experimento II, de 1 a 42 dias de idade, foram utlizados 160 frangos de corte, distribuídos em um delineamento inteiramente aleatorizado com 5 tratamentos e 4 repetições. Os tratamentos utilizados foram semelhantes aos descritos no Experimento I. Na primeira fase, grupos de 8 aves foram criadas em gaiolas de metabolismo providas de aquecimento. Na segunda fase, a partir dos 21 dias de idade, as aves foram transferidas de gaiolas e mantidas 4 aves por grupo. As gaiolas eram equipadas com bandeja para coleta de excretas e comedouro e bebedouro tipo calha. Houve um aumento significativo (P<0,05) da ingestão de água pelas aves alimentadas com 7,5% e 10,0% de glicerina no 4° e 8° dias de idade. O consumo de ração aumentou (P<0,05) no 8° e 12° dias de idade das aves nos tratamentos com 2,5% e 7,5% de glicerina e houve redução do consumo com 10,0% de glicerina. A umidade das excretas aumentou (P<0,05) para dietas contendo 5,0%, 7,5% e 10,0% de glicerina no 16° e 20° dias de idade. As diferenças não foram significativas para essas variáveis nas idades. Não houve diferença (P>0,05) para a umidade do conteúdo ileal das aves aos 42 dias. Houve efeito linear (P<0,01) dos níveis de glicerina, aumentando a profundidade de cripta e reduzindo a relação vilo:cripta, sem afetar o comprimento da vilosidade. Níveis elevados de glicerina na ração podem induzir alterações metabólicas em frangos de corte com aumento do glicerol sanguíneo, do consumo de água, da umidade das excretas e da taxa de reposição celular do epitélio intestinal. / Two experiments were conducted with the objective of identifying the metabolic response of chickens fed diets containing glycerin and verify the effect of this ingredient in some blood parameters. In Experiment I, 100 broilers with 20 days of age were housed in metabolism cages and distributed in a completely randomized design with 5 treatments, 4 replications and 5 birds per cage. Treatments consisted of a control diet, based on corn and soybean meal, and four other diets with 2.5%, 5.0%, 7.5% and 10.0% biodiesel glycerin. The glycerin contained 83.63% glycerol, 1.83% sodium and 397 mg/kg of methanol and the metabolizable energy value of 3.258 kcal/kg was considered for formulation. The diets were isoenergetic and with values adjusted for the other nutrientes. For the blood parameters (cholesterol and triglycerides), glycerol concentration in the liver and liver weight there was no significant effect (P>0.05) of inclusion of glycerin. The glycerol concentration in the serum of birds consuming 10% glycerin increased during the first 9 days of ingestion of diet (P<0.05), then returning to the level of the control until 35 d of age. In Experiment II, from 1 to 42 days of age, 160 chicks were distributed in a completely randomized design with 5 treatments and 4 replications. The treatments were similar to those described in Experiment I. In the first phase, groups of 8 birds were raised in heated brooders. In the second phase, from 21 to 42 d of age, the birds were transferred of cages and maintained in groups of 4 birds. The cages were equipped with a tray for excreta collection and trough type feeder and drinker. There was a significant increase (P<0.05) in water intake in birds fed 7.5% and 10.0% of glycerin on the 4th and 8th days. The feed intake increased (P<0.05) on the 8th and 12th daysfor the birds in treatments with 2.5% and 7.5% of glycerin and there was a decrease d consumption with 10.0% glycerin. The moisture of the excreta increased (P<0.05) for diets containing 5.0%, 7.5% and 10.0% glycerin at the 16th and 20th days old. The differences were not significant for these variables at the other ages. There was no difference (P>0.05) for moisture in the ileal contents of birds at 42 days. There was a linear effect (P<0.01) of the levels of glycerin, increasing crypt depth and reducing the ratio villus:crypt ratio, without affecting the length of the villi. High levels of glycerin in the diet may induce metabolic changes in broilers with increase in blood glycerol, water consumption, moisture of the excreta and in the rate of cell replacement in the intestinal epithelium.
70

Avaliação do uso glicerina em dietas para frangos de corte nas fases pré-inicial e final / Evaluation of the use glycerin in diets for broilers in the pre-starter and final phases

Leonardo Willian de Freitas 01 February 2013 (has links)
Dois experimentos foram conduzidos com o objetivo de avaliar a utilização de dietas com níveis crescentes de glicerina de biodiesel apenas na fase pré-inicial (1 a 7 dias) e apenas na fase final (35 a 42 dias de idade) de frangos de corte, respectivamente. As variáveis analisadas incluíram o desempenho, o rendimento de carcaça e cortes, a retenção de umidade em pintos aos 7 dias, a umidade de cama, a incidência de pododermatite, os níveis plasmáticos de colesterol e triglicerídeos e o custo da ração referente ao ganho de peso. Os tratamentos consistiram de dietas formuladas com 0%, 5% ou 10% de glicerina, sendo isonutritivas e formuladas à base de milho, farelo de soja e óleo de milho. A glicerina usada continha 83,6% de glicerol, 11,2% de água, 1,83% de sódio e 397 mg/kg de metanol, com energia metabolizável estimada de 3258 kcal/kg. No Experimento I, as dietas com glicerina foram fornecidas apenas na fase pré-inicial ou durante todo o ciclo de criação com 1610 aves em um delineamento inteiramente casualizado com 5 tratamentos e 7 repetições. Na primeira semana, as dietas com glicerina promoveram melhora significativa no ganho de peso e na conversão alimentar, sem afetar o consumo de ração e viabilidade. Essa melhora não foi mantida após os 14 dias de idade. Não houve efeito de tratamentos sobre o ganho de peso, consumo de ração e conversão alimentar. Entretanto, houve redução significativa na viabilidade aos 35 dias de idade das aves com 10% de glicerina por todo ciclo, mas não aos 42 dias; ao final do experimento, o índice de eficiência produtiva desse tratamento sofreu redução significativa. A umidade da cama das aves do tratamento com 10% de glicerina por todo ciclo de criação foi mais alta que dos demais a partir dos 21 dias, entretanto a incidência de pododermatite foi mais severa tanto para 5% como para 10% de glicerina por todo ciclo. Os níveis e tempos de fornecimento de glicerina não afetaram o rendimento de carcaça e de cortes ou a gordura abdominal. No experimento II, as dietas experimentais foram fornecidas a 819 frangos apenas na semana final de criação em um experimento inteiramente casualizado com 3 tratamentos e 7 repetições. O desempenho e o custo de ração por kg de ganho de peso não foram afetados pelos tratamentos. Nos Experimentos I e II, as rações contendo glicerina durante todo o ciclo ou apenas na última semana não resultaram em alteração nas concentrações plasmáticas de triglicerídeos e colesterol dos frangos. Dietas contendo 5% ou 10% de glicerina na fase pré-inicial ou 5% de glicerina continuamente não afetam a produtividade de frangos de corte, enquanto o nível de 10% durante todo o ciclo foi prejudicial. Esse mesmo nível de glicerina pode ser usado na dieta dos 35 aos 42 dias de idade sem afetar as aves. / Two experiments were conducted to evaluate the use of diets with increasing levels of biodiesel glycerin only in pre-starter (1-7 days) and only in the final phase (35-42 days of age) of broilers, respectively. The variables analyzed included the performance, carcass and parts yield, moisture retention in chicks at 7 days, litter moisture, incidence of foot pad dermatitis, plasma levels of cholesterol and triglycerides and diet cost related to weight gain. Treatments were isonutritive diets based on corn, soybean meal and corn oil containing 0, 5 and 10% glycerin. The glycerin used contained 83.6% glycerol, 11.2% water, 1.83% sodium and 397 mg/kg methanol, with estimated metabolizable energy value of 3,258 kcal/kg. In the first experiment, diets with glycerin were provided only in the pre-starter or for the entire growth period with 1610 birds in a completely randomized design with 5 treatments and 7 replications. In the first week, diets with glycerin resulted in significant improvement in weight gain and feed conversion without affecting feed intake and viability. This improvement was not sustained after 14 days of age. There was no effect of treatments on weight gain, feed intake and feed conversion. However, there was a significant reduction in viability at 35 days of age for the birds with 10% glycerin throughout the cycle, but not at 42 days; at the end of the experiment, the productivity index of this treatment was significantly decreased. Litter moisture for the treatment with 10% glycerin throughout the cycle was higher than the for the others from the 21 days, however the incidence of foot pad dermatitis was more severe for both 5% and 10% glycerin treatments for the entire period. The levels and periods of glycerin feeding did not affect carcass and parts yield and abdominal fat. In experiment II, the experimental diets were provided to 819 chickens only in the final week of growth in a completely randomized design with 3 treatments and 7 replications. The performance and feed cost per kg of weight gain were not affected by treatments. In Experiments I and II, the diets containing glycerin throughout the cycle or just in the last week resulted in no change in plasma concentrations of triglycerides and cholesterol of chickens. Diets containing 5% or 10% glycerin in the pre-starter phase or 5% glycerin continually did not affect the productivity of broilers, while the 10% level throughout the cycle was detrimental. This same level of glycerin can be used in the diet from 35 to 42 days without affecting the birds.

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