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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.
21

Teores de fibra em detergente neutro em dietas de alto concentrado para cordeiros em terminação / Neutral detergente fiber concentrations in high concentrate diets for finishing lambs

Brochado, Thaís 21 October 2016 (has links)
Embora dietas de alto concentrado sejam comumente utilizadas para acabamento de cordeiros, informações sobre o efeito de teores mínimos de fibra em detergente neutro (FDN) sobre o desempenho de cordeiros são limitadas. O objetivo deste estudo foi avaliar os efeitos da inclusão de baixos teores de FDN em dieta de alto concentrado sobre desempenho, eficiência alimentar, características de carcaça, variáveis sanguíneas e ruminais de cordeiros em terminação. Vinte e quatro cordeiros machos, não castrados (peso vivo inicial de 24,55 ± 2,2 kg) foram distribuídos aleatoriamente em baias individuais, em delineamento inteiramente casualizado, com três tratamentos e oito repetições. Os tratamentos foram teores de FDN na dieta de 15, 20 e 25% com base na matéria seca. As dietas foram compostas de milho, farelo de soja, minerais e silagem de milho, e foram oferecidas duas vezes por dia, com controle diário do alimento ofertado e sobra para determinação da ingestão de matéria seca (IMS). Os animais foram pesados semanalmente e abatidos após 50 dias de confinamento, com peso vivo final de 40,48 ± 2,3 kg. Peso de carcaça quente e fria (PCQ e PCF), bem como o rendimento de carcaça quente e fria (RCQ e RCF) foram medidos. Após a evisceração, foram coletados fluido e conteúdo ruminal para determinação de ácidos graxos de cadeia curta e protozoários. Os dados foram submetidos à análise de regressão, utilizando o pacote estatístico SAS® (versão 9.0, 2002). Cordeiros alimentados com diferentes teores de FDN, apresentaram efeito linear crescente sobre a IMS e o consumo alimentar residual (CAR) conforme aumentou o teor de FDN na dieta. O ganho médio diário (GMD) e as demais variáveis de eficiência alimentar não diferiram estatisticamente entre os tratamentos. Os teores crescentes de FDN na dieta ocasionou diminuição do PCQ, RCQ e RCF, e não houve efeito significativo sobre as demais variáveis de carcaça. As variáveis sanguíneas e ruminais não foram alteradas pelos tratamentos, sugerindo que as dietas utilizadas com alto teor de concentrado e diferentes teores de FDN para cordeiros em terminação proporcionaram homeostase aos animais e ambiente adequado para fermentação ruminal. De modo geral, as dietas com teores baixos de FDN não alteraram o GMD, mas tiveram efeito sobre CAR, peso e rendimentos de carcaça aumentaram e não proporcionaram alterações fisiológicas e ruminais. / Although high concentrate diets are commonly used for finishing lambs, information about the effect of minimum levels of neutral detergent fiber (NDF) on performance is limited. The purpose of this study was to evaluate the effects of increasing dietary fiber levels on performance, feed efficiency and parameters of carcass, blood and rumen of finishing lambs fed high concentrate diet. Twenty four uncastrated male lambs (initial body weight of 24.55 ± 2.2 kg) were randomly assigned to 24 individual pens, in a complete randomized design with three treatments and eight replicates. Treatments were dietary NDF levels of 15, 20 and 25% based on dry matter. Diets were composed of corn, soybean meal, minerals and corn silage, and were offered twice a day with refusals daily measured to determine dry matter intake (DMI). Animals were weighed weekly and slaughtered after 50 d of feedlot, with body weight of 40.48 ± 2.3 kg. Hot and cold carcass weight (HCW and CCW) as well as hot and cold carcass yield (HCY and CCY) were measured. After evisceration, fluid and rumen contents were collected to determine fatty acid short chain and protozoa. Data were submitted to analysis of regression, using the statistical software SAS (version 9.0, 2002). Lambs fed with increasing levels of NDF had a linear efeect on IMS and residual feed intake (RFI). The average daily gain (ADG) and other food efficiency variables were not statistically different between treatments. Increasing levels of NDF in the diet caused a decrease in HCW, HCY and CCY, and there was no significant effect on other carcass variables. Blood and rumen variables were not affected by treatments, suggesting that the diets with high concentrate and different levels of NDF for finishing lambs provided homeostasis animals and adequate environment for rumen fermentation. In general, diets with low NDF did not alter the ADG, but had no effect on RFI, weight and carcass yield increased and did not provide physiological and ruminal changes.
22

Adding Values, Upholstery Concepts for Automotives Using Smart Textiles

Jul, Lene January 2007 (has links)
New textile materials are constantly being brought into the automotive field, and automobile design is a leader in innovative and spectacular developments where smart textile materials are used. The main elements of the current project are textile material research, automotive research, design and development of two upholstery concepts for automotives using smart textiles. The added values are RFI/EMI (Radio Frequency Interference / Electro Magnetic Interference) shielding qualities, light emitting, light reflective and antistatic qualities. Values in the smart-textile area are obtained through choice of material and textile techniques. Transportation textiles are considered high performance technical fabrics, but they must also meet the aesthetic demands of the market. In the current project the design is inspired by Japanese architectural thinking and strives to relate to outdoor environment to reduce the border between indoor and outdoor environment. The inspiration source is water surfaces. The colour setting is also inspired by water surfaces. Material selection is based on the chosen added values, material qualities, appearance and availability. The result of the work is two different upholstery concepts visualizing qualities of smart materials and requests the automotive field. Sprinkle is an upholstery with light emitting, light reflective and antistatic values. The materials used are monofilament, polyester and electroluminescent wires. Wave is an upholstery design with antistatic, light reflective and RFI/Emi shielding qualities. The materials used are stainless steel yarn, rubco and monofilament. / <p>Program: Konstnärligt masterprogram i mode- och textildesign</p><p>Uppsatsnivå: D</p>
23

Radio frequency interference modeling and mitigation in wireless receivers

Gulati, Kapil 21 October 2011 (has links)
In wireless communication systems, receivers have generally been designed under the assumption that the additive noise in system is Gaussian. Wireless receivers, however, are affected by radio frequency interference (RFI) generated from various sources such as other wireless users, switching electronics, and computational platforms. RFI is well modeled using non-Gaussian impulsive statistics and can severely degrade the communication performance of wireless receivers designed under the assumption of additive Gaussian noise. Methods to avoid, cancel, or reduce RFI have been an active area of research over the past three decades. In practice, RFI cannot be completely avoided or canceled at the receiver. This dissertation derives the statistics of the residual RFI and utilizes them to analyze and improve the communication performance of wireless receivers. The primary contributions of this dissertation are to (i) derive instantaneous statistics of co-channel interference in a field of Poisson and Poisson-Poisson clustered interferers, (ii) characterize throughput, delay, and reliability of decentralized wireless networks with temporal correlation, and (iii) design pre-filters to mitigate RFI in wireless receivers. / text
24

Characterisation of the radio noise environment in New Zealand

Banks, Paul Russell January 2009 (has links)
A methodology for the measurement of the radio frequency environment close to the radio noise floor is presented for urban, suburban and rural areas within New Zealand for the purposes of characterisation and trend monitoring by radio spectrum managers. Flux density measurements in bands within a range of frequencies from 80 MHz to 8 GHz have been made in urban, suburban and rural areas of New Zealand during 2007 and 2008. An analysis of the band occupancy is presented in summary form. These summaries are intended as a starting point for radio spectrum usage and can be used as a reference for any future measurements. A description of the computer directories and charts resulting from these measurements, using 20 MHz bandwidths have also been included. All the results for the work have been collated in a set of computer directories named “NZRFI Directories 2007 2008”, which are intended as a reference for use in the determination of local activity in particular frequency ranges. A disc with the full range measurement spectral density charts and channel occupancy charts accompanies this work. Also included on the disc are sets of 20 MHz band charts for some urban, suburban and rural location measurements.
25

Characterisation of the radio noise environment in New Zealand

Banks, Paul Russell January 2009 (has links)
A methodology for the measurement of the radio frequency environment close to the radio noise floor is presented for urban, suburban and rural areas within New Zealand for the purposes of characterisation and trend monitoring by radio spectrum managers. Flux density measurements in bands within a range of frequencies from 80 MHz to 8 GHz have been made in urban, suburban and rural areas of New Zealand during 2007 and 2008. An analysis of the band occupancy is presented in summary form. These summaries are intended as a starting point for radio spectrum usage and can be used as a reference for any future measurements. A description of the computer directories and charts resulting from these measurements, using 20 MHz bandwidths have also been included. All the results for the work have been collated in a set of computer directories named “NZRFI Directories 2007 2008”, which are intended as a reference for use in the determination of local activity in particular frequency ranges. A disc with the full range measurement spectral density charts and channel occupancy charts accompanies this work. Also included on the disc are sets of 20 MHz band charts for some urban, suburban and rural location measurements.
26

Characterisation of the radio noise environment in New Zealand

Banks, Paul Russell January 2009 (has links)
A methodology for the measurement of the radio frequency environment close to the radio noise floor is presented for urban, suburban and rural areas within New Zealand for the purposes of characterisation and trend monitoring by radio spectrum managers. Flux density measurements in bands within a range of frequencies from 80 MHz to 8 GHz have been made in urban, suburban and rural areas of New Zealand during 2007 and 2008. An analysis of the band occupancy is presented in summary form. These summaries are intended as a starting point for radio spectrum usage and can be used as a reference for any future measurements. A description of the computer directories and charts resulting from these measurements, using 20 MHz bandwidths have also been included. All the results for the work have been collated in a set of computer directories named “NZRFI Directories 2007 2008”, which are intended as a reference for use in the determination of local activity in particular frequency ranges. A disc with the full range measurement spectral density charts and channel occupancy charts accompanies this work. Also included on the disc are sets of 20 MHz band charts for some urban, suburban and rural location measurements.
27

Traitement spatial des interférences pour les radiotélescopes de nouvelle génération / Radio Frequency Interference spatial processing for modern radio telescopes

Hellbourg, Grégory 31 January 2014 (has links)
La radio astronomie étudie les sources cosmiques au travers de leur rayonnement dans le domaine radio. Les astronomes, utilisateurs passifs du spectre électromagnétique, ont à faire face à une pollution radio de plus en plus importante. Cette thèse s’intéresse particulièrement aux interférences radio d’origine humaine (RFI), et comment les observations radio astronomiques peuvent être réalisées en bandes de fréquences non-protégées. Les approches classiques consistent à contrôler les paramètres statistiques d’une observation. Une fois détectées, les données polluées sont retirées avant post-traitement. En plus d’autres avantages techniques par rapport aux radiotélescopes paraboliques classiques, les réseaux d’antennes offrent une information spatiale lors d’une observation astronomique. La diversité spatiale entre source cosmique d’intérêt (SCOI) et RFI peut être exploitée pour développer des traitements spatiaux d’interférences. Après la formulation d’un module de données multidimensionnel, une technique de soustraction de sous espace RFI est introduite. Cette technique consiste à soustraire la contribution des RFI aux données d’une observation. La projection orthogonale a déjà été considérée auparavant. Cependant, l’orthogonalité requise entre CSOI et RFI pour retrouver une source d’intérêt non biaisée ne peut vraisemblablement pas être satisfaite. Une approche basée sur une projection oblique est introduite afin de pallier à cette condition. Les techniques de projections sont comparées aux techniques classiques de beamforming en termes de réjection de l’interférence et de récupération de la source d’intérêt. Le sous-espace RFI est inconnu de manière générale et se doit d’être estimé. Plusieurs techniques permettant cette estimation, basées sur des propriétés statistiques des RFI et sources cosmiques, sont également présentées et comparées. Les différentes techniques ont été appliquées à des données astronomiques délivrées par le radio télescope Européen LOFAR. Enfin, une implémentation d’un algorithme de traitement spatial d’interférences sur le démonstrateur EMBRACE est présenté. / Radio astronomy studies cosmic sources through their radio emissions. As passive users, astronomers have to deal with an increasingly corrupted radio spectrum. The research presented here focuses on man-made Radio Frequency Interference (RFI), and how astronomical observations can be performed in non-protected frequency bands. Traditional approaches consist in monitoring radio telescopes output data through statistical parameters. Once detected, the corrupted data is removed before further processing. Besides other technical advantages compared to single dish radio telescopes, antenna arrays provide spatial information about astronomical observations. The spatial diversity between cosmic sources-of-interest (CSOI) and RFI can be exploited to develop spatial RFI processing. After formulating a multidimensional radio astronomical data model, an interference subspace subtraction technique is introduced. This approach consists in subtracting RFI contributions from antenna array radio telescopes data. Orthogonal projection applied to astronomical observation vector spaces has already been considered by the past. The orthogonality between RFI and CSOI subspaces is required to recover the CSOI without bias. In order to avoid this latter requirement, an oblique projection approach is here proposed. The projection techniques are compared to classic beamforming techniques in term of interference rejection and CSOI recovering. Being usually unknown, the RFI subspace has to be estimated. Several techniques allowing this estimation, based on statistical properties of RFI and cosmic sources (whiteness and cyclostationarity), are also presented and compared. The different techniques have been applied to real astronomical data, provided by the European radio telescope LOFAR. A last section presents an RFI mitigation algorithm implemented on the demonstrator EMBRACE.
28

Méthode d'analyse en vue de l'amélioration des interférences électromagnétiques dans les systèmes intégrés radio fréquence / Methodology of analysis for the improvement of the electromagnetic interferences in RF integrated systems

Dupoux, Céline 11 March 2011 (has links)
Les travaux présentés dans ce mémoire proposent une méthodologie d'étude des interférences électromagnétiques dans les systèmes intégrés RF. Cette thèse se focalise sur les problèmes de couplage rayonné en champ proche entre différentes parties d'une puce électronique ou entre circuits intégrés d'une carte.Ensuite cette méthodologie est appliquée sur deux cas d'études à différentes échelles, dans le premier cas l'étude du couplage entre un amplificateur de puissance 3G et un transceiver est présentée puis un modèle de couplage est réalisé reproduisant les effets parasites observés lors des mesures. Puis une étude pour extraire et évaluer les couplages entre blocs, ici inductance d'un VCO et structures proches, d'une puce électronique. Ensuite un modèle d'émission champ proche de ce circuit est proposé.Ces travaux mettent en évidence l'intérêt de réaliser des études CEM à chaque phase de conception d'un circuit ou d'un système ainsi que l'intérêt des mesures champ proche qui permettent de réaliser de l'investigation et du diagnostic CEM / The work presented in this PhD suggest a methodology for the study of electromagnetic interference in RF integrated systems. This thesis focuses on the problems of near-field radiated coupling between different parts of a chip or between ICs.Then this methodology is applied to two case studies on different scales, in the first case study the coupling between a 3G power amplifier and a transceiver is presented then a model of the coupling is made reproducing parasitic effects observed in measurements. Then a study to extract and evaluate the coupling between blocks, between a VCO inductor and nearby structures of a microchip. Then a near-field emission model of this circuit is proposed.These works demonstrate the interest of EMC studies in all phases of designing a circuit or system and the interest of near-field measurements that allow the realization of the investigation and diagnosis of EMC
29

Efeitos da dieta e da eficiência alimentar de touros jovens nelore sobre a expressão gênica e acúmulo intracelular de lipídeos em embriões pré-implantacionais produzidos in vitro / Effects of diet and feed efficiency of young nelore bulls on gene expression and intracellular accumulation of lipids in pre-implantation embryos produced in vitro

Peres, Anelise Ribeiro [UNESP] 27 July 2018 (has links)
Submitted by ANELISE RIBEIRO PERES (ane.medvet@hotmail.com) on 2018-09-18T23:21:32Z No. of bitstreams: 1 TESE DOUTORADO definitivo_ANELISE.pdf: 1833795 bytes, checksum: 8953d732ef286f330a73fc84245f9111 (MD5) / Approved for entry into archive by Neli Silvia Pereira null (nelisps@fcav.unesp.br) on 2018-09-19T16:44:11Z (GMT) No. of bitstreams: 1 peres_ar_dr_jabo.pdf: 1833795 bytes, checksum: 8953d732ef286f330a73fc84245f9111 (MD5) / Made available in DSpace on 2018-09-19T16:44:11Z (GMT). No. of bitstreams: 1 peres_ar_dr_jabo.pdf: 1833795 bytes, checksum: 8953d732ef286f330a73fc84245f9111 (MD5) Previous issue date: 2018-07-27 / Na bovinocultura de corte, a alimentação corresponde ao maior custo associado à produção de carne. A avaliação do consumo alimentar residual (CAR) tem sido uma ferramenta importante para direcionar a seleção de bovinos de corte e otimizar economicamente esta atividade. No entanto, alguns estudos mostram uma diminuição da motilidade, do perímetro escrotal, uma menor taxa de prenhez e parto em animais eficientes para CAR. Uma estratégia para solucionar tais problemas é a suplementação ácidos graxos poliinsaturados (AGPs) que não apenas aumentam a densidade energética da dieta, mas também atuam na melhoria do desempenho reprodutivo. No entanto, o ideal é que tais características de seleção para CAR e efeito da suplementação com AGPs sejam passadas à prole, assim o objetivo desse trabalho foi avaliar o efeito paterno da seleção para consumo alimentar residual (CAR) e da suplementação dos touros com AGs para a PIVE, o acúmulo de lipídio embrionário e a expressão de genes. Animais classificados em baixo CAR e alto CAR foram utilizados no experimento. O delineamento experimental obedeceu a um esquema fatorial 2 x 2 (CAR x Suplementação), a análise estatística foi realizada pelo programa JPM (versão 5.0.1, SAS Institute). Após a amostragem, os animais foram separados aleatoriamente em dois grupos: com suplementação de AGs protegido e com suplementação controle (sem AGs protegido). O experimento foi composto por quatro tratamentos, o sêmen dos touros foi congelado (4 tratamentos), sendo 6 animais suplementados com AGs protegido (3 baixo CAR e 3 alto CAR) e 6 animais com suplementação controle, sem AGs (3 baixo CAR e 3 alto CAR). O sêmen foi utilizado para produção in vitro de embriões; os blastocistos foram reservados para análise da quantificação de lipídios e os blastocistos expandidos para análise da expressão gênica. A quantificação de lipídios foi avaliada utilizando o corante Sudan Black B 1% e as imagens foram analisadas pelo programa Image J (National Institutes of Health, USA). A análise de expressão gênica dos embriões foi feita pela técnica de qPCR utilizando o sistema de micro-fluídica Biomark HD (Fluidigm®, South San Francisco, CA, USA). Não houve diferença na produção in vitro de embriões oriundos de animais CAR- ou CAR+, nem entre os tratamentos suplementados com AGs. Embriões de touros CAR+ apresentaram maior conteúdo lipídico quando comparado com o grupo CAR-. Os genes que apresentaram diferença associados à dieta foram o HMOX1, SREBF1 e o GPX4. Os referentes ao perfil CAR que diferiram foram o PLAC8, PPARGC1A e o NFE2L2. Os relacionados com a interação entre dieta e CAR que apresentaram diferença foram o RPLP0, ATF4, H3F3A, HSF1, HMGCS1, SLC2A5, NANOG, REST e o GPX4. Conclui-se que a dieta e a seleção para CAR dos touros afetou a expressão gênica dos embriões produzidos in vitro utilizando o sêmen desses animais. / In beef cattle, feed corresponds to the highest cost associated with meat production. The evaluation of the selection for residual feed intake (RFI) has been an important tool to direct the selection of beef cattle and economically optimize this activity. However, some studies show a decrease in motility, scrotal perimeter, a lower pregnancy and calving rate in efficient animals for RFI. One strategy to solve such problems is polyunsaturated fatty acid (PUFA) supplementation that not only increases the energy density of the diet, but also improves reproductive performance. However, the ideal is that these characteristics of selection for RFI and effect of the supplementation with PUFA are passed to offspring, so the aim of this work was to evaluate the paternal effect of selection for residual feed intake and supplementation of bulls with fatty acids for in vitro produced embryos (IVPE), accumulation of embryonic lipid and gene expression. Animals classified under low RFI and high RFI were used in the experiment. The experimental design was based on a 2 x 2 factorial scheme (RFI x Supplementation), the statistical analysis was performed by the JPM program (version 5.0.1, SAS Institute). The animals were randomly divided into two groups: with protected fatty acids supplementation and with control supplementation (without protected fatty acids). The experiment was composed of four treatments, the semen of the bulls was frozen (4 treatments), 6 animals were supplemented with protected fatty acids (3 low RFI and 3 high RFI) and 6 animals with control supplementation, without protected fatty acids (3 low RFI and 3 high RFI). The semen was used for IVPE; blastocysts were reserved for analysis of lipid quantification and expanded blastocysts for analysis of gene expression. The quantification of lipids was evaluated using the Sudan Black B 1% dye and the images were analyzed by program Image J (National Institutes of Health, USA). The gene expression analysis of the embryos was done by the qPCR technique using the Biomark HD microfluidic system (Fluidigm®, South San Francisco, CA, USA). There was no difference in the in vitro production of embryos from RFI- or RFI+ animals, there was also no difference between treatments (supplementation). Embryos from RFI+ bulls presented higher intracytoplasmic lipid content than embryos from RFI- bulls. The genes that showed differences associated with the diet were HMOX1, SREBF1 and GPX4. The RFI associated genes that differed were PLAC8, PPARGC1A and NFE2L2. Those related to the interaction between diet and RFI that presented difference were RPLP0, ATF4, H3F3A, HSF1, HMGCS1, SLC2A5, NANOG, REST and GPX4. In conclusion, the diet and the selection for RFI of the bulls affected the gene expression of the embryos produced in vitro using the semen of these animals.
30

Teores de fibra em detergente neutro em dietas de alto concentrado para cordeiros em terminação / Neutral detergente fiber concentrations in high concentrate diets for finishing lambs

Thaís Brochado 21 October 2016 (has links)
Embora dietas de alto concentrado sejam comumente utilizadas para acabamento de cordeiros, informações sobre o efeito de teores mínimos de fibra em detergente neutro (FDN) sobre o desempenho de cordeiros são limitadas. O objetivo deste estudo foi avaliar os efeitos da inclusão de baixos teores de FDN em dieta de alto concentrado sobre desempenho, eficiência alimentar, características de carcaça, variáveis sanguíneas e ruminais de cordeiros em terminação. Vinte e quatro cordeiros machos, não castrados (peso vivo inicial de 24,55 ± 2,2 kg) foram distribuídos aleatoriamente em baias individuais, em delineamento inteiramente casualizado, com três tratamentos e oito repetições. Os tratamentos foram teores de FDN na dieta de 15, 20 e 25% com base na matéria seca. As dietas foram compostas de milho, farelo de soja, minerais e silagem de milho, e foram oferecidas duas vezes por dia, com controle diário do alimento ofertado e sobra para determinação da ingestão de matéria seca (IMS). Os animais foram pesados semanalmente e abatidos após 50 dias de confinamento, com peso vivo final de 40,48 ± 2,3 kg. Peso de carcaça quente e fria (PCQ e PCF), bem como o rendimento de carcaça quente e fria (RCQ e RCF) foram medidos. Após a evisceração, foram coletados fluido e conteúdo ruminal para determinação de ácidos graxos de cadeia curta e protozoários. Os dados foram submetidos à análise de regressão, utilizando o pacote estatístico SAS® (versão 9.0, 2002). Cordeiros alimentados com diferentes teores de FDN, apresentaram efeito linear crescente sobre a IMS e o consumo alimentar residual (CAR) conforme aumentou o teor de FDN na dieta. O ganho médio diário (GMD) e as demais variáveis de eficiência alimentar não diferiram estatisticamente entre os tratamentos. Os teores crescentes de FDN na dieta ocasionou diminuição do PCQ, RCQ e RCF, e não houve efeito significativo sobre as demais variáveis de carcaça. As variáveis sanguíneas e ruminais não foram alteradas pelos tratamentos, sugerindo que as dietas utilizadas com alto teor de concentrado e diferentes teores de FDN para cordeiros em terminação proporcionaram homeostase aos animais e ambiente adequado para fermentação ruminal. De modo geral, as dietas com teores baixos de FDN não alteraram o GMD, mas tiveram efeito sobre CAR, peso e rendimentos de carcaça aumentaram e não proporcionaram alterações fisiológicas e ruminais. / Although high concentrate diets are commonly used for finishing lambs, information about the effect of minimum levels of neutral detergent fiber (NDF) on performance is limited. The purpose of this study was to evaluate the effects of increasing dietary fiber levels on performance, feed efficiency and parameters of carcass, blood and rumen of finishing lambs fed high concentrate diet. Twenty four uncastrated male lambs (initial body weight of 24.55 ± 2.2 kg) were randomly assigned to 24 individual pens, in a complete randomized design with three treatments and eight replicates. Treatments were dietary NDF levels of 15, 20 and 25% based on dry matter. Diets were composed of corn, soybean meal, minerals and corn silage, and were offered twice a day with refusals daily measured to determine dry matter intake (DMI). Animals were weighed weekly and slaughtered after 50 d of feedlot, with body weight of 40.48 ± 2.3 kg. Hot and cold carcass weight (HCW and CCW) as well as hot and cold carcass yield (HCY and CCY) were measured. After evisceration, fluid and rumen contents were collected to determine fatty acid short chain and protozoa. Data were submitted to analysis of regression, using the statistical software SAS (version 9.0, 2002). Lambs fed with increasing levels of NDF had a linear efeect on IMS and residual feed intake (RFI). The average daily gain (ADG) and other food efficiency variables were not statistically different between treatments. Increasing levels of NDF in the diet caused a decrease in HCW, HCY and CCY, and there was no significant effect on other carcass variables. Blood and rumen variables were not affected by treatments, suggesting that the diets with high concentrate and different levels of NDF for finishing lambs provided homeostasis animals and adequate environment for rumen fermentation. In general, diets with low NDF did not alter the ADG, but had no effect on RFI, weight and carcass yield increased and did not provide physiological and ruminal changes.

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