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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.
11

Socio-Economic Transformation and Gender Relations in Lao PDR

Khouangvichit, Damdouane January 2010 (has links)
The aim of this study is to examine socio-economic transformation and gender relations in Lao PDR after the adoption of economic liberalization by the Lao government in the late 1980s. Against a background of general socio-economic transformation in Laos the main focus of the study is on the local level, with emphasis on how people in their everyday lives have engaged with and handled the changes. The application of economic liberalization shaped new conditions for people in local communities, and various livelihoods strategies were adopted under the new circumstances. The study examines gender relations, livelihoods and actors of change in two different contexts of globalization. The first context is the case of foreign direct investment in the Sepone mine, the largest gold-copper mine in the country located in Vilabury district, Savannakhet province. Five villages located close to the mine and directly affected by the operation were chosen as research site. The second case is the context of international tourism development in the small town of Vang Vieng, situated halfway between Vientiane Capital and the world heritage town of Luangprabang. The purpose with the two case studies is to examine how changes take place in different places of the same country under the same political direction and development policy. The study is inspired by theories of space and place and the view that phenomena are place-based and different places are constituted by different socio-spatial relations. The findings show that profound changes took place both in the economic and social-cultural spheres, including in gender relations. The two contexts experienced different processes of changes: in the context of Vilabury district, the transformation was produced through top-down development and created a dependency pattern where new social inequalities and social stratification emerged through unequal access to the new resources of the villagers. In the context of Vang Vieng and the expansion of international tourism, the development process proceeded more through a bottom-up pattern; the villagers perceived they were important actors of development, had more equal access to resources and could define livelihood strategies by themselves.
12

Across the Borders : A Study of Counter-Trafficking Work in Lao PDR

Hansson, Emma January 2009 (has links)
<p>In the wake of state borders becoming more porous the flows of people crossing them in search for opportunities have increased. This trend is evident in Greater Mekong Sub region where the economic boom of Thailand attracts thousands of migrant workers every year from neighboring countries making Thai industries dependent on the cheap labor. Alongside these developments, human trafficking, the slave trade of our time, has emerged as an increasing challenge.</p><p>In Lao PDR the historic ties to Thailand make for a long history of cross-border relations and flows. With the relative economic differences, labor migration to the richer neighbor is becoming an accepted way of improving family conditions. However, the risks involved, exploitation and trafficking, are not widely known in the communities.</p><p>Counter-trafficking work in Lao PDR has been evolving over the passed 10 years. This study has, through an ethnographic approach to organizational work combined with reflections and observations, tried to create a picture of the counter-trafficking work on the ground. Using semi-structured interviews projects, aims and assumptions could be derived and three main problems identified: Trafficking is hard to separate from labor migration, thus making it hard to effectively target; there is a dissonance between perceived and actual inter-sector communication, and; the trafficking sector is isolated from other sectors as dialogue across sector borders appear to be nonexistent. Reasons given for these discords mainly came down to dependency on donors and a need to meet their requirements. Essentially it seems that organizations working with this open-border phenomenon are rigidly closed to each other.</p>
13

Contradictions of Neoliberal Development Interventions and Market Transition in Northern Lao PDR

Polonyi, Anna Elizabeth 24 July 2013 (has links)
This thesis examines the trajectory and role of development within the context of transition from a command to market economy, in a northern region of the Lao PDR. It looks at how the long-term effects of development interventions have contributed to a context of regional integration where the role of foreign investment and the private sector are increasing. In particular, it examines the role of development interventions in the processes of diversification and differentiation that accompany market integration. The village of Ban Jai illustrates this process as a site where despite the failures of development projects a diversification of livelihoods have developed. The implementation of UNDP projects in Ban Jai raises questions regarding the role of international projects and suggests that rather than alleviating poverty they produce a chain of effects that contribute to the tensions that result from structural changes to the village household economy. My analysis examines the tensions produced by such shifts and how villagers negotiate their engagement with the market economy. The experience of women traders illustrates how relations of solidarity are reworked in an attempt to negotiate tensions produced through processes of market integration. As structural shifts take place with increasing economic integration, international agencies also respond in particular ways by shifting strategies. I also ask what changes shifts in strategy introduce at the local level and how this intersects with the way policies are rationalized by local officials and the UNDP. An examination of this trajectory over a period of two decades, suggests that changing strategies in development have involved a shifting role between international development organizations and the private sector. I ask what kind of context this intersection of structural shifts, policy shifts and institutional shifts produces on the ground and how such shifts are negotiated locally.
14

Star cluster formation and molecular cloud destruction caused by radiative feedback / 星団形成と輻射フィードバックによる分子雲破壊

Inoguchi, Mutsuko 23 March 2022 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第23704号 / 理博第4794号 / 新制||理||1686(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 嶺重 慎, 教授 長田 哲也, 准教授 細川 隆史 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
15

Development of a novel rep-inducible tomato leaf curl virus expression system

Williams, Brett Robert January 2007 (has links)
Pathogen-derived resistance (PDR) strategies, particularly those based on post-transcriptional gene silencing, have been used with great success for the generation of transgenic plants with resistance to RNA viruses. In contrast, a suitable strategy for transgenic resistance to ssDNA plant viruses, including those viruses belonging to the Geminiviridae, has remained elusive. Further, there is no convincing evidence that either post-transcriptional gene silencing, or pathogen-derived resistance in general, would be broadly applicable to ssDNA plant viruses. Researchers at QUT have been developing a novel resistance strategy against ssDNA viruses based on virus-activated expression of a stably integrated suicide gene. The strategy, based on InPAct (In Plant Activation) technology, relies on a &quotsplit" suicide gene cassette being arranged in such a way that expression of a lethal ribonuclease (barnase) is dependent on the virus-encoded replication-associated protein (Rep). Upon infection, Rep mediates the release of the construct resulting in the reconstitution of a transcribable and translatable episomal suicide gene expression cassette. The research for this PhD describes the development of an InPAct vector designed to confer resistance to Tomato leaf curl begomovirus (ToLCV), a major cause of disease in Solanaceous crops in the tropics and subtropics. ToLCV-based InPAct vectors were constructed based upon two ToLCV isolates from Australia and North Vietnam. Prior to the generation of InPAct cassettes, the entire ToLCV-[Au] and ToLCV-Vie intergenic regions (IRs) were embedded within the castorbean catalase intron of a β-glucuronidase expression vector to determine the effect of the IR upon transcript processing. Using transient reporter gene assays in tobacco NT-1 cells, it was demonstrated that the ToLCV IRs both contained cryptic intron splice sites which interfered with efficient transcript processing and GUS expression. A series of truncations to the IRs were subsequently made to identify the potential cryptic intron splice sites and/or interfering sequences in both the ToLCV-[Au] and ToLCV-Vie IRs. The final truncated IRs, which were used in the construction the InPAct cassettes, comprised approximately 100 bp and appeared to contain all the necessary cis-acting elements required for efficient rolling circle replication (RCR). Using histochemical GUS assays and Southern analyses, the InPAct cassettes were shown to be activated and replicated only in the presence of the cognate viral Rep. GUS expression levels were shown to be further enhanced in the presence of the ToLCV replication-enhancer protein (REn) and by the addition of the Tobacco yellow dwarf mastrevirus origin of second strand synthesis into the cassette. Under these conditions, Rep-activated GUS expression from the InPAct vectors was found to reach levels similar to that of the benchmark CaMV 35S promoter. Fifteen independent transgenic lines containing the ToLCV-[Au] and -Vie InPAct-GUS cassettes were generated by Agrobacterium-mediated transformation of tobacco leaf discs. Using agroinfiltration and histochemical assays, Rep-mediated activation of the InPAct cassettes and subsequent GUS expression was demonstrated in 11 out of the 15 lines tested; six of which showed expression levels equivalent to, or higher than, that obtained using a CaMV 35S promoter control. Evidence for activation of the integrated InPAct cassettes at the molecular level was provided by Southern analyses, with showed both linear and open circular forms of the replicating InPAct episome in genomic DNA extracted from infiltrated leaf tissue. Following the demonstration of Rep-activatable reporter gene expression and episomal replication of the ToLCV-based InPAct-GUS vectors using transient and stable tobacco transformation assays, new ToLCV-based InPAct vectors were designed to express the lethal RNase, barnase, in an attempt to generate virus resistant plants. Although transient assays in NT-1 cells demonstrated some &quotleaky" expression of barnase from the InPAct vectors, the level of barnase-mediated cell death from the InPAct vectors was found to be significantly increased in the presence of the cognate Rep and REn. Thirteen independently transformed tobacco lines containing the ToLCV-[Au] InPAct-barnase cassette were generated by Agrobacterium-mediated transformation of tobacco leaf discs. However, agroinfiltration of these plants with ToLCV Rep and REn failed to activate a barnase response. Subsequent molecular analyses on two transgenic lines revealed that both contained mutations in the barnase-coding gene in a region known to encode the active site. These mutations were presumed to result from the leaky barnase expression during initial stages of the Agrobacterium transformation which would favour the selection of barnase mutant InPAct plants. To overcome the problems associated with leaky expression of barnase, a barstar-expression cassette was included in the ToLCV-[Au] InPAct-barnase cassette. Transient assays in non-transgenic tobacco leaves demonstrated that the basal levels of barstar expressed from the modified InPAct vector were sufficient to negate the effects of leaky barnase expression. Importantly, however, the level of barnase expression in the presence of Rep and REn was shown to be sufficient to overcome the basal levels of barstar. Seventeen independently transformed lines were generated with the ToLCV-[Au] InPAct-barnase/barstar cassette, and analysis of one line revealed the presence of an uncorrupted barnase-coding region. Using transient agroinfiltration assays, seven of the transgenic lines showed varying levels of cognate Rep and REn-activated, barnase-induced cell death. Fifteen transgenic lines were challenged with ToLCV-[Au] by injection of recombinant Agrobacteria containing an infectious ToLCV clone. Unfortunately, all lines displayed typical ToLCV symptoms and tested positive for virus by PCR at 28 days post-inoculation. The inability of the InPAct cassette to confer resistance to ToLCV may have been due to one or a combination of factors, including (i) a delay in barnase-induced cell death, (ii) homology-dependent silencing of the integrated cassette, (iii) generally low-level, Rep-activated barnase expression or (iv) excessive virus load due to the artifical method of inoculation. This study details the first report of a ToLCV-based InPAct system for Rep-induced transgene expression in planta. Despite failing to generate ToLCV-resistant plants, the research findings will provide a solid foundation to develop a more effective InPAct vector and ultimately assist in the generation of transgenic plants with resistance to ToLCV and potentially other ssDNA plant viruses, particularly the begomoviruses.
16

Improving high dose rate and pulsed dose rate prostate brachytherapy - alternative prostate definition and treatment delivery verification methods

Howie, Andrew Gordon, howie.andrew@gmail.com January 2009 (has links)
Brachytherapy is a form of radiotherapy in which radioactive sources are placed at short distances from, or even inside the target volume. The use of high dose rate brachytherapy is a widely accepted and clinically proven treatment for some stages of prostate cancer. The aim of this project was to investigate potential improvements on two of the most important aspects of high dose rate (HDR) and pulsed dose rate (PDR) prostate brachytherapy - prostate definition and treatment delivery verification. The use of magnetic resonance (MR) imaging in addition to the conventional computed tomography (CT) imaging methods currently used routinely for brachytherapy planning may provide some benefit in accurately defining the prostate and surrounding critical structures. The methods used in this project involved analysis of data sets provided by two Radiation Oncologists. The results presented showed inter-observer and intra-observer variations in the size and shape of the prostate, as well as analysis of the dosimetric differences that may be reported due to the differences in prostate size and shape. The results also included analysis of critical structure dosimetry - dose to the surrounding radio-sensitive rectum and urethra. In summary, the results showed that the prostate was defined to be smaller using MR imaging than CT, however the consistency between Oncologists was not significantly improved using MR imaging. MR imaging may be useful in reducing the dose to normal tissue surrounding the prostate and in obtaining better coverage of the smaller target volume, without compromising the critical structures. The use of LiF:Mg,Ti thermoluminescent dosimeters (TLDs) is a potential avenue for in vivo dose verification of an HDR or PDR prostate brachytherapy treatment plan. This project included a phantom study of these TLDs with the aim to determine their feasibility for clinical use. Cylindrical TLD rods (6 mm length x 1 mm diameter) were used, as these fit inside the brachytherapy needles implanted into the prostate, and therefore had potential to be used clinically to verify the dose delivered in the prostate. This study was extended to include determination of a correction factor to allow an independent radiation source (6 MV photon beam from a linear accelerator) to be used to obtain control readings for this relative dosimetric method. The results showed these TLDs to be a promising in vivo dosimeter for prostate brachytherapy with potential errors in the order of 4%. Their potential lies in the fact that they could detect and flag significant calculation errors in treatment plans, and they utilise equipment used routinely for external beam radiotherapy dosimetry in many treatment facilities, reducing the cost of implementing such a procedure.
17

Riverine border practices : people's everyday lives on the Thai-Lao Mekong border

Wisaijorn, Thanachate January 2018 (has links)
Pluralities of people s crossings of the Mekong Thai-Lao border occur as locals subvert, reject, ignore, and embrace the logic of the national border. From a state-centric point of view, the everyday movements of these people, who rely mainly on a subsistence economy and have their own modes of crossing, are undocumented. I argue that people s mobility co-exists with the practice of sedentary assumption. The aim of this thesis is to promote theory related to the Third Space in Borderland Studies by the presentation and analysis of people s pluralities in border-crossings. The borderland area of Khong Chiam (Thailand)-Sanasomboun (Lao PDR) is the location of an in-between state in which spatial negotiations, temporal negotiations, and negotiations of political subjectivities contribute to the nature of mobility in the Third Space. To achieve the objective of this thesis, ethnographic methodology was used over six months of fieldwork from March to September 2016, and included participant observations, interviews and essay-readings that involved 110 participants in the borderland site. People s movements across the Mekong River border occur daily without formal state approval. From the perspective of the Thai Ban, the river is a lived space in which they catch food and use for transport. However, their interpretation of the Mekong as the state boundary does not completely disappear. This thesis examines the everyday banal pluralities of the Thai Ban s border-crossings by weaving together the three concepts of space, temporality, and negotiations of political subjectivities. The spatial and temporal negotiations involved in the border-crossings shape and are shaped by this other interpretation of the Mekong as a lived space, and different political subjectivities contribute to the pluralities of the crossings. The presentation of these pluralities of border-crossings adds to Borderland Studies specifically and the social sciences in general in the development of an understanding of the Third Space. As this thesis focuses on people s mobility at quasi-state checkpoints and in areas along the Mekong Thai-Lao border with no border checkpoints, it is suggested that future research examines the everyday practices of border-crossings at land borders.
18

Inclusão de tanino condensado em dietas com alto teor de concentrado para bovinos de corte / Influence of condensed tannin in beef steers fed high concentrate diet

Mezzomo, Rafael 23 February 2010 (has links)
Made available in DSpace on 2015-03-26T13:54:54Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1431828 bytes, checksum: e7d74eb0d250f3b5781c47a91dd51f20 (MD5) Previous issue date: 2010-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / This trial was conducted to evaluate the effect of condensed tannin (TN) associated or not with a true protein source on intake, ruminal and total digestibility, ruminal digestion rate and urinary nitrogen excretion in beef steers fed high concentrate diet (87% of DM). Four crossbred steers (407 kg of average BW) fitted with rumen cannula were assigned to a 4x4 latin square design, arranged in a 2x2 factorial arrangement. Steers were fed a basal diet based on cracked corn, whole cottonseed, sugar-cane bagasse, mineral mixture and 1 out of four supplements: soybean meal with condensed tannin (SMT); soybean meal without condensed tannin (SM); condensed tannin without soybean meal (TN) and a treatment without both soybean meal and condensed tannin (BS). Quebracho extract were used as tannin source, included to provide 4 g of tannin/100 g of diet DM. Intake of DM and nutrients was not affected (P>0.10) by TN supplementation. However, there was an effect (P<0.10) of TN supplementation on ether extract digestibility. A smaller (P<0.10) concentration of urinary urea nitrogen (71.94 vs. 53.62) and total nitrogen (86.43 vs. 74.07) were observed in the animals supplemented with condensed tannin. Serum urea nitrogen concentration did not differ (P>0.10) among treatments. There was an interaction (P<0.10) between condensed tannin and soybean mean on ruminal digestibility and digestion rate of crude protein (CP), where when supplemented with soybean meal the condensed tannin reduced the ruminal digestibility of 46.92 to 33.46 and consequently, reduced the digestion rate of CP. Crude protein intake increased (P<0.10) with the inclusion of soybean meal in the supplement. No differences in DM passage rate were observed (P>0.10) among treatments. Urinary urea nitrogen and total nitrogen were higher in the animals supplemented with soybean meal. The nitrogen balance indicated that the use of TN improved the efficiency of nitrogen utilization (P<0.10), however, no differences were observed when soybean meal was added to the diet (P>0.10). There was an interaction (P<0.10) between condensed tannin and soybean mean supplementation on flux of rumen undegradable protein (RUP), metabolizable protein (MP) and on the ratio MP:CP. In the presence of soybean meal the addition of TN increased the flux of RUP (302.24 to 416.02), MP (540.23 to 671.03) and improved the ratio MP:CP (58.69 to 46.54). The yield of microbial protein on the abomasum and the microbial efficiency did not differ among treatments (P>0.10). There was no effect of TN supplementation (P>0.10) on ruminal pH, VFA and ammonia (N-NH3) concentration. N-NH3 increased and ruminal pH decreased with the inclusion of soybean meal (P<0.10) in the diet. The use of condensed tannin as an additive in cattle fed high concentrate diet using soybean meal as true protein source decreases the digestion rate and ruminal degradability of crude protein without affecting feed intake. The utilization of condensed tannin as an additive in cattle fed high concentrate diet using soybean meal as true protein source implies in positive effects on efficiency of N utilization, increasing the flux of metabolizable and decreasing nitrogen excretion with no changes in ruminal fermentation, optimizing the nitrogen assimilation by the animal. / Quatro bovinos de corte, com peso corporal médio de 407 ±12 kg, fistulados no rúmen e abomaso, foram distribuídos em um quadrado latino 4 x 4, em esquema fatorial 2 x 2, com o objetivo de avaliar a eficiência da inclusão de tanino condensado e/ou farelo de soja a dietas de bovinos de corte submetidos a altos níveis de concentrado sobre o consumo, digestibilidade aparente total e parcial, fluxo de nutrientes, excreção de nitrogênio e uréia pela urina, balanço de nitrogênio (BN), perfil protéico, perfil de ácidos graxos voláteis (AGV) no rúmen, pH ruminal, concentração de amônia ruminal e eficiência microbiana. A alimentação basal dos animais foi composta por ração contendo 87% de concentrado e constituída por milho (moído grosso), caroço de algodão, bagaço de cana in natura e núcleo mineral, fornecida ad libitum. Os quatro tratamentos foram: dieta com farelo de soja e tanino condensado (FST); dieta com farelo de soja sem tanino condensado (FS); dieta sem farelo de soja e com tanino condensado (CAT) e dieta sem farelo de soja e sem tanino condensado (CA). Como fonte de tanino condensado utilizou-se extrato de quebracho. Não se verificou efeito (P>0,10) da suplementação com TC sobre o consumo de MS e de nutrientes. Verificou-se efeito positivo (P<0,10) da suplementação com TC sobre a digestibilidade do extrato etéreo. Os valores de nitrogênio uréico na urina (NUU) e nitrogênio total na urina (NU) foram menores (P<0,10) com a suplementação de tanino condensado. Os níveis de nitrogênio uréico no soro (NUS) não foram diferentes (P>0,10) entre os tratamentos avaliados. O balanço de nitrogênio (BN) indicou que a utilização de tanino condensado melhorou a eficiência de utilização de nitrogênio (P<0,10). Verificou-se efeito da interação (P<0,10) entre tanino condensado e farelo de soja sobre a digestibilidade ruminal da proteína, taxa de digestão da PB, a proteína não degradada no rúmen (PNDR), a estimativa de proteína metabolizável (PM) e sobre a razão PM:PB, onde a suplementação conjunta com TC e farelo de soja reduziu a degradabilidade ruminal e, consequentemente, a taxa de digestão, aumentou o fluxo de PNDR e de PM e melhorou a relação PM:PB. A quantidade de proteína microbiana no abomaso e a eficiência microbiana não sofreram alterações nos tratamentos avaliados (P>0,10). Não houve diferença no pH, AGV e nitrogênio amoniacal (N-NH3) ruminal frente à adição de tanino condensado, porém, os parâmetros ruminais foram influenciados pelo tempo de coleta das amostras. Verificou-se aumento do consumo de proteína bruta (P<0,10) frente à inclusão de farelo de soja. A digestibilidade ruminal e total do extrato etéreo foi maior com a remoção do farelo de soja da dieta. A taxa de passagem da MS não diferiu entre os tratamentos avaliados. A inclusão de farelo de soja à dieta acarretou aumento (P<0,10) nas taxas de digestão da MO, PB e FDNcp. Os níveis de NUU e NU foram mais elevados com a suplementação com FS. Houve aumento do N ingerido e do N excretado via urina e fezes (P<0,10) quando adicionado farelo de soja à dieta, não havendo modificações no BN (P>0,10). O N-NH3 aumentou e o pH ruminal diminuiu com a inclusão de farelo de soja (P<0,10). As concentrações de AGV não se diferenciaram com a adição de farelo de soja. Verificou-se que a utilização de tanino condensado (0,4% sobre a MS da dieta) como aditivo para bovinos de corte alimentados com dietas de alto teor de concentrado e com farelo de soja como fonte de proteína verdadeira diminui a taxa de digestão e degradabilidade ruminal da proteína bruta, sem alterar o consumo dos animais, implicando em efeitos positivos sobre a utilização da proteína bruta, aumentando os níveis de proteína metabolizável e diminuindo o desperdicio de nitrogênio sem alterar os parâmetros ruminais, otimizando a assimilação de nitrogênio no ambiente ruminal.
19

Across the Borders : A Study of Counter-Trafficking Work in Lao PDR

Hansson, Emma January 2009 (has links)
In the wake of state borders becoming more porous the flows of people crossing them in search for opportunities have increased. This trend is evident in Greater Mekong Sub region where the economic boom of Thailand attracts thousands of migrant workers every year from neighboring countries making Thai industries dependent on the cheap labor. Alongside these developments, human trafficking, the slave trade of our time, has emerged as an increasing challenge. In Lao PDR the historic ties to Thailand make for a long history of cross-border relations and flows. With the relative economic differences, labor migration to the richer neighbor is becoming an accepted way of improving family conditions. However, the risks involved, exploitation and trafficking, are not widely known in the communities. Counter-trafficking work in Lao PDR has been evolving over the passed 10 years. This study has, through an ethnographic approach to organizational work combined with reflections and observations, tried to create a picture of the counter-trafficking work on the ground. Using semi-structured interviews projects, aims and assumptions could be derived and three main problems identified: Trafficking is hard to separate from labor migration, thus making it hard to effectively target; there is a dissonance between perceived and actual inter-sector communication, and; the trafficking sector is isolated from other sectors as dialogue across sector borders appear to be nonexistent. Reasons given for these discords mainly came down to dependency on donors and a need to meet their requirements. Essentially it seems that organizations working with this open-border phenomenon are rigidly closed to each other.
20

Comportamento alimentar, metabolismo ruminal e estabilidade do leite de vacas alimentadas com milho floculado e diferentes níveis de degradabilidade da proteína / Feeding behavior, ruminal metabolism and milk stability of cows fed steam flakes and different levels of protein degradability

Danielle de Cássia Martins da Fonseca 09 February 2018 (has links)
O presente estudo foi desenvolvido em dois experimentos: 1) Tipo de processamento do milho e a relação PDR:PNDR sobre a fermentação ruminal, comportamento alimentar e seletividade ingestiva de vacas leiteiras cujos objetivos foram: a) avaliar o efeito do tipo de processamento do milho (floculado ou moído) e a relação da proteína degradável (PDR) e não degradável no rúmen (PNDR) (alta ou baixa) sobre a fermentação ruminal, o comportamento alimentar e a seletividade ingestiva de vacas leiteiras durante o período experimental; b) avaliar o efeito a curto prazo da troca da dieta contendomilho moído ou floculado e alta ou baixa relação PDR:PNDR sobre o consumo de matéria seca, produção e estabilidade do leite (teste do álcool, pH, cálcio iônico, estabilidade térmica e alcoólica) de vacas leiteiras durante período de adaptação. Foram utilizadas 20 vacas da raça Holandesa, com 162 &#177; 70 DEL, 666 &#177; 68 kg de peso corporal, 3,15 &#177; 0,48 de escore de condição corporal e 36,0 &#177; 7,78 kg/vaca/ dia de produção de leite. Os resultados de metabolismo ruminal indicaram que o milho floculado reduziu a relação acetato:propionato e a concentração de ácido acético (%) e aumentou as concentrações dos ácidos valérico (&micro;mol/L) e de propiônico (%) e o pH fecal em relação ao milho moído. Quanto ao comportamento alimentar, observou-se que o uso de milho floculado associado à alta relação PDR:PNDR e a utilização de milho moído associado à baixa relação PDR:PNDR reduziram os tempos de alimentação (TAL/ kg de MS ingerida) e de ruminação (TRU/ kg de MS ingerida) entretanto, o uso de milho floculado associado à alta ou à baixa relação PDR:PNDR aumentaram o tempo de ruminação (TRU/ kg de FDN consumido). Já para índice de seleção notou-se que a rejeição de partículas longas (&gt; 19,0 mm) foi menor em vacas alimentadas com milho floculado em relação às alimentadas com moído. 2) Efeito a curto prazo da troca da dieta sobre a produção e estabilidade do leite de vacas da raça Holandesa que teve por objetivo avaliar o efeito do dia de troca da dieta com diferentes fontes de carboidrato não fibroso associado ou não a inclusão de tamponante/alcalinizante sobre CMS, produção e estabilidade do leite (teste do álcool, pH, cálcio iônico, estabilidade térmica e alcoólica). Foram utilizadas 16 vacas da raça Holandesa, com 130 &#177; 81 DEL, peso corporal de 660 &#177; 62 kg e produção média de leite de 28,5 &#177; 4,79 kg/vaca/dia. O milho moído associado à alta ou à baixa relação PDR:PNDR aumentou o CMS, entretanto o fornecimento de dieta contendo a alta relação PDR:PNDR associada ao milho moído ou floculado apresentaram redução na PL. O uso de milho floculado associado à alta relação PDR:PNDR aumentou o valor de pH das amostras de leite e em todos os tratamentos testados a concentração de Cai apresentou redução. O uso de milho floculado associado ao aumento da relação PDR:PNDR causou redução na estabilidade alcoólica do leite e o uso do milho moído associado a baixa relação PDR:PNDR aumentou a estabilidade do leite ao teste do álcool. O CMS foi a única variável que apresentou efeito da dieta, em que o uso de milho moído sem a inclusão de tamp/alc aumentou o CMS. Sendo assim, durante o período de adaptação, o efeito a curto prazo de troca foi mais nítido nas dietas contendo milho processado associado à proteínas de diferentes degradabilidades ruminal do que nas dietas contendo fontes de carboidratos não fibrosos associados à inclusão ou não de tamp/alc. / The present study was developed in two experiments: 1) Corn processing type and the RDP:RUP ratio on ruminal fermentation, feeding behavior and ingestive selectivity of dairy cows. The objectives were: to evaluate the effect of corn processing type (flocculated or ground) and the ratio (hight or low) of degradable (RDP) and non-degradable protein (RUP) on ruminal fermentation, feed behavior and ingestive selectivity of dairy cows during the experimental period. Indeed to evaluate the short-term effect of dietary exchange containing either ground or flocculated corn and high or low RDP: RUP ratio on dry matter intake, milk yield and stability (alcohol test, pH, ionic calcium, of dairy cows during adaptation period. Twenty Holstein cows were used, with 162 &#177; 70 DIM, 666 &#177; 68 kg body weight, 3.15 &#177; 0.48 body condition score and 36.0 &#177; 7.78 kg / cow / day of milk yield. The results of ruminal metabolism indicated that the flocculated corn reduced the acetate: propionate ratio and the acetic acid concentration (%) and increased the concentrations of valeric (&micro;mol / L) and propionic acid (%) and fecal pH in relation to ground corn. As regards feed behavior, it was observed that the use of flocculated corn associated with high RDP:RUP ratio and the use of milled corn associated with low RDP:RUP ratio reduced feeding times (TAL / kg of intake DM) and rumination (TRU / kg of DM ingested). However, the use of flocculated corn associated with high or low RDP:RUP ratios increased rumination time (TRU / kg of NDF consumed). For the selection index, it was noted that the rejection of long particles (&gt; 19.0 mm) was lower in cows fed flocculated maize than those fed with milled corn. 2) Short-term effect of the diet change on the production and stability of Holstein cows milk that aimed to evaluate the effect of the diet change day with different sources of non-fibrous carbohydrate associated or not with the inclusion of buffer / alkalinizing on DMI, milk production and stability (alcohol test, pH, ionic calcium, thermal and alcoholic stability). Sixteen Holstein cows, 130 &#177; 81 DIM, body weight of 660 &#177; 62 kg and mean milk yield of 28.5 &#177; 4.79 kg / cow / day were used. Ground corn associated with high or low RDP:RUP ratios increased of intake DM; however, the diet containing the high RDP:RUP ratio associated to ground or flocculated corn showed a decrease in milk yield. The use of flocculated corn associated with high RDP:RUP ratio increased the pH value of milk samples; and in all tested treatments; the concentration of Cai presented reduction. The use of flocculated corn associated with the increase of the RDP:RUP ratio caused a decrease in the milk alcoholic stability while the use of ground corn associated with a low RDP:RUP ratio increased this variable. The intake DM was the only variable that presented a dietary effect, in which the use of ground corn without the inclusion of buffer/alk increased intake DM. Thus, during the adaptation period, the short-term effect of exchange was more pronounced in diets containing processed corn associated with proteins of different ruminal degradability than in diets containing sources of non-fibrous carbohydrates associated with the inclusion of buffer/alk .

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