Thesis (Ph.D.)(Food Science)--University of Pretoria, 2005. / Includes summary. Includes bibliographical references.

Thesis (doctoral)--Helsinki University of Technology, 2005. / Includes bibliographical references. Also available on the World Wide Web. Myös verkkojulkaisuna.

Submitted by JOSE EDER PEREIRA DA SILVA null (eder.jeps@terra.com.br) on 2016-05-21T00:05:06Z No. of bitstreams: 1 Dissertação_José_Ede_P_Silva_com_ficha (1).pdf: 2003164 bytes, checksum: d776b0516852a32e5763381a780cbe16 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-24T12:16:24Z (GMT) No. of bitstreams: 1 silva_jep_me_bot.pdf: 2003164 bytes, checksum: d776b0516852a32e5763381a780cbe16 (MD5) / Made available in DSpace on 2016-05-24T12:16:24Z (GMT). No. of bitstreams: 1 silva_jep_me_bot.pdf: 2003164 bytes, checksum: d776b0516852a32e5763381a780cbe16 (MD5) Previous issue date: 2016-03-24 / Tendo em vista os problemas ambientais relativos as contaminações do solo e da agua oriundas dos dejetos produzidos em propriedades rurais, objetivou-se avaliar economicamente um biodigestor de fluxo contínuo, instalado na Escola Técnica Estadual “Orlando Quagliato”, situada no município de Santa Cruz do Rio Pardo-SP, bem como o processo de biodigestão anaeróbia e consequente produção de biofertilizante e biogás, oriundos dos dejetos de suínos e humanos. Os dejetos foram provenientes da suinocultura, que conta com 15 matrizes totalizando 148 animais, e dejetos humanos referente aos blocos de alojamentos para 200 alunos residentes, os quais diariamente são enviados para o biodigestor. O biodigestor em questão foi instalado com intuito de diminuir a contaminação do meio ambiente, produzir biogás e biofertilizante para utilização nos projetos produtivos da própria instituição escolar. Foram realizadas análises físico-químicas e microbiológicas do biofertilizante com a finalidade de avaliar a sua qualidade, no que tange a composição química e presença de microorganismos patogênicos para definição de sua utilização na agricultura. Considerando a produção de dejetos, realizou-se estimativa da produção de biogás, objetivando o potencial das receitas do processo. Foram analisados os custos de implantação, manutenção e depreciação. Os benefícios anuais foram dados pelo valor econômico dos nutrientes presentes no biofertilizante e pela produção de biogás estimada. Também foram estimados indicadores de viabilidade econômica, como Valor Presente Líquido (VPL), Taxa Interna de Retorno (TIR), PayBack (PB) e Ponto de Equilíbrio, utilizando uma taxa de desconto de 10,38% a.a. O investimento inicial para implantação atualizado foi de R$ 184.601,84 e os custos anuais do sistema foram de R$ 1.218,12 com manutenção e R$ 18.460,00 com depreciação. O benefício obtido com o emprego do biofertilizante foi de R$ 6.267,05.ano-1 e com produção de biogás equivalente estimada em R$ 24.594,86.ano-1, totalizando uma receita de R$ 30.861,91, expondo benefícios superiores aos custos anuais. Ficou evidenciado que tanto o biogás quanto o biofertilizante não são aproveitados plenamente, demonstrando ainda que o projeto foi superdimensionado na sua implantação considerando o plantel de suínos existentes, embora existam perspectivas para aumento do setor suinícola. / In view of the environmental problems of soil contamination to and from the water coming from the waste produced in farms aimed to economically evaluate a continuous flow digester, installed in the State Technical School "Orlando Quagliato", located in the municipality of Santa Cruz do Rio Pardo-SP, as well as the process of anaerobic digestion and consequent production of bio-fertilizer and biogas, derived from pig manure and human. The waste came from pig farming, which has 15 arrays totaling 148 animals, and human waste relating to the accommodation blocks for 200 resident students, who every day are sent to the digester. The biodigester in question was installed in order to reduce contamination of the environment, produce biogas and biofertilizers for use in productive projects of their own educational institution. physico-chemical and microbiological analyzes of biofertilizers were conducted in order to assess their quality, with respect to chemical composition and the presence of pathogenic microorganisms to define its use in agriculture. Considering the production of waste, there was estimated biogas production, aiming the potential revenue in the process. deployment costs, maintenance and depreciation were analyzed. The annual benefits were given the economic value of the nutrients present in biofertilizers and the estimated biogas production. Were also estimated economic viability indicators, such as net present value (NPV), internal rate of return (IRR), Payback (PB) and Balance, using a discount rate of 10.38% p.a. The initial investment was estimated at R$ 184,601.84 and the system annual costs were R$ 1.218,12 with maintenance and R$ 18.460,00 with depreciation. The benefit obtained by biofertilizer use was R$ 6.267,05.ano-1 and biogas production equivalent around R$ 24.594,86.ano-1, totaling a revenue of R$ 30.861,91, exhibiting superior benefits annual costs. This study revealed that as much biogas as biofertilizers are not used fully, further demonstrating that the project was oversized in its implementation, considering the amount of existing animals, although there are prospects for increased this sector.

Made available in DSpace on 2014-06-11T19:32:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-02-26Bitstream added on 2014-06-13T20:04:44Z : No. of bitstreams: 1 rivera_ar_dr_jabo.pdf: 387270 bytes, checksum: 3259bdff37d857577baed98527c8e44d (MD5) / O objetivo deste estudo foi estimar a taxa de passagem em cabras leiteiras gestantes. O mesmo foi dividido em dois experimentos usando cabras multíparas, não lactantes, gestantes. O primeiro estudo foi realizado em 36 cabras, multíparas, com peso médio de 50,6 ± 7,7 kg, distribuídas nos tratamentos de acordo com a raça (Saanen e Alpina); tipo de prenhez (simples e gemelar) e período de gestação (80, 110 e 140 dias). O delineamento experimental foi completamente casualizado e teve como objetivo estimar a taxa de passagem de cabras leiteiras durante a gestação. O segundo estudo foi realizado em 49 cabras multíparas, não lactantes, com gestação gemelar e peso médio de 49.0 kg ± 8.9, distribuídas nos tratamentos de acordo com o período de prenhez (80,110,140 dias), tipo de restrição alimentar (sem restrição, moderada e severa), e raça (Saanen e Alpina). O delineamento experimental foi em blocos casualizados e o objetivo foi estimar a taxa de passagem em cabras leiteiras submetidas a resrição alimentar ao longo da prenhez. Para a estimativa da taxa de passagem foram fornecidos indicadores externos (itérbio para fase sólida e Cr-EDTA para fase líquida) e foi usada a metodologia do esvaziamento do trato digestório em animais abatidos para a coleta das amostras e foi mensurada a quantidade de gordura e o peso sorporal previo ao abate. A digestibilidade da MS e da MO aumenta em cabras com gestação gemelar no primeiro terço da prenhez e decresce ao final da gestação. Cabras com gestação simples apresentam maior digestibilidade da MS e do FDN na fase final da prenhez. Cabras leiterias gestantes não alteram a taxa de passagem dos sólidos no rúmen durante a prenhez. Cabras Saanen apresentaram maior taxa de diluição ruminal. A taxa de passagem dos sólidos em cabras gestantes submetidas a restrição alimentar varia entre 0.03 a 0.10/h... / The objective of this study was to estimate passage rate in pregnancy goats. It was divided in three studies using goats multiparous, no milking, pregnancy. The first study was in 36 goats multiparous and mean weight was 50,6 kg ± 7,7 distributed in the treatments according breed (Saanen and Oberhasli), gestational age (80, 110, 140 days) and type of pregnancy (simples or twin). Design experimental was completely randomized and the objective was to estimate passage rate in milking goats during the pregnancy. The second study was in 49 goats multiparous, no milking, with twin pregnancy and mean weight 49.0 kg ± 8.9, distributed in the treatments according breed (Saanen and Oberhasli), gestational age (80, 110, 140 days) and nutritional restriction (no restriction, moderate and severe). Design experimental was in blocks randomized and the objective was to estimate passage rate in milking goats with nutritional restriction during pregnancy. For both studies were given orally external markers (ytterbium for solid phase and Cr- EDTA for liquid phase). Slaughter method was used and evacuation for sample collecting from gastro-intestinal tract and quantity of fat was measured. Digestibility assay was performed and the DMI was daily measured. Milking pregnancy goats not change ruminal passage rate during the pregnancy. DM, and organic matter increased in early pregnancy in twin pregnancy goats and decreased in late gestation. Simple pregnancy goats increased DM and NDF digestibility in late gestation. Pregnancy milking goats not changed passage rate of particles in the rumen. Saanen goats showed greater ruminal dilution rate. Passage rate in nutritional restriction goats range was 0,03 to 0,10 /h. Oberhasli breed with moderate restriction increased ruminal passage rate of solid phase in the secondthird of gestation. Passage rate alteration in pregnancy goats is associated to breed, nutritional level and gestational age

Global warming along with energy demand and rising prices of natural energy resources have motivated studies to find some renewable and clean energy. The use of algae as third generation biofuel can avoid the competition for farmland and algae can be considered as a potential future source of renewable energy. Algae can be used for biogas production through anaerobic digestion (AD). Fucus vesiculosus and Fucus serratus are the two dominating species of brown seaweed growing in the Baltic sea in the southwest of Sweden. Pretreatment can significantly affect the biogas production since hydrolysis of algae cell wall structure is a rate-limiting step in AD process. In this study, four different pretreatments: mechanical, microwave (600W, 2min), ultrasonic (110V, 15min), and microwave combined with ultrasonic (600W, 2min;110V, 15min) were applied to the seaweed and then co-digested with biogas plant leachate. The aim was to investigate the biogas production and methane yield from AD after these pretreatments. The results showed when comparing with mechanical pretreated only, that the ultrasonic, ultrasonic combined with microwave and microwave pretreatments could obtain increased cumulative methane yields with 167%, 185% and 156% , respectively. The maximum methane yield was 260 ml/g∙VS with combined pretreatment after 20 days of digestion. The ultrasonic combined with microwave pretreatment showed a significant improvement of methane yield when comparing with mechanical pretreatment.

La digestion anaérobie représente un élément clé dans la dynamique de développement durable contribuant à la valorisation verte des déchets organiques sous forme de biogaz et d'engrais. Dans le cadre de ce travail de thèse franco-libanais, nous cherchons à valoriser le marc de raisin, déchet majeur et principal sous-produit issu de la viniculture, par la digestion anaérobie, afin de générer de l’énergie dite verte sous forme de méthane. Dans un premier temps, le potentiel méthane du marc de raisin est démontré, validant notre biomasse végétale comme source potentielle d’énergie. Des informations détaillées sur les productions maximales de méthane à partir du marc entier, des pulpes et des pépins, séparément, sont obtenues en mode batch à 37 °C. La faisabilité technique du procédé est alors validée suite à une extrapolation au mode continu. De plus, des essais d’acclimatation du digesteur continu à la température moyenne de la vallée de la Bekaa (25 °C) permettent de simuler et d’adapter le système au milieu libanais. D’autre part, nous avons mené une caractérisation bio-physico-chimique de différents cépages de marcs de raisins en provenance de différentes régions viticoles. La diversité du contenu lignocellulosique et du potentiel méthanogène des substrats choisis a été mise en évidence. Une corrélation négative existe, en particulier, entre le potentiel méthane et les teneurs en lignine et en cellulose. Afin d’intensifier la production de méthane, le dimensionnement des digesteurs anaérobies en mode continu est optimisé en déterminant un optimum de fonctionnement pour une charge appliquée de 3,7 kg DCO m-3 j-1 et un temps de séjour de 20 jours. Enfin, nous évaluons les effets d’une variété de prétraitements (congélation, traitement alcalin, traitement acide, ultrasons et champs électriques pulsés) sur la production de méthane et sur la biodégradabilité des fractions. Le couplage du traitement alcalin à 10% NaOH avec la congélation à -20 °C s’avère être le meilleur procédé d’intensification. / Anaerobic digestion is considered to be a crucial part of a sustainable development strategy, contributing to the green valorization of organic waste as biogas and fertilizers. As part of this doctoral thesis, we explored the valorization of grape pomace, the major waste and main by-product of winemaking, by anaerobic digestion, to generate green energy in the form of methane. Firstly, the methane potential of grape pomace is demonstrated, validating our vegetal biomass as a potential source of energy. Detailed information on the maximum production of methane from whole pomace, pulps and seeds are obtained in batch mode at 37 °C. The technical feasibility of the process is then validated following an extrapolation to the continuous mode. Moreover, the acclimation of the continuous digester at the average temperature of the Beqaa valley (25 °C) allowed to simulate and adapt the current system to the Lebanese environment. On another note, we carried out a bio- physico-chemical characterization of different grape varieties from different wine-growing areas. The diversity of the lignocellulosic content and the methane potential of the selected substrates was highlighted. A negative correlation exists, in particular, between the methane potential and the lignin and cellulose fractions. In order to intensify methane production, we conducted an optimization of anaerobic digesters dimensioning in continuous mode by determining an optimum of operation for an applied load of 3.7 kg COD m-3 d-1 and a residence time of 20 days. Finally, we evaluated the effects of a variety of pretreatments (freezing, alkaline treatment, acid treatment, ultrasounds and pulsed electric fields) on the methane production and the biodegradability of lignocellulosic fractions. The coupling of the alkaline treatment using 10% NaOH with freezing at -20 °C seems to be the best intensification process.

Made available in DSpace on 2014-06-11T19:34:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-03-05Bitstream added on 2014-06-13T19:44:40Z : No. of bitstreams: 1 silva_sp_dr_jabo.pdf: 600408 bytes, checksum: b43f7a9a28f47c878fa0f20f91178587 (MD5) / Foram realizados dois estudos, o primeiro teve como objetivo estudar se e como a classe sexual e a restrição alimentar afetam a taxa de passagem em caprinos alimentados com dieta com baixa fibra. Foram utilizados 51 caprinos da raça Saanen, sendo 18 machos não castrados, 18 machos castrados e 15 fêmeas, os quais foram sorteados segundo o tipo de restrição: ausente (RA), moderada (RM) e severa (RS). O experimento iniciou quando os animais atingiram em média 30 kg PC e finalizou quando os caprinos que receberam o tratamento RA atingiram peso corporal médio de 45 kg. Para mensuração da taxa de passagem, no rúmen, ceco e cólon, adotou-se a técnica de abate e foi utilizado como indicador interno a FDNi. Adotou-se o delineamento em blocos casualizado, em esquema fatorial 3x3 com seis repetições de machos não-castrados e castrados e cinco repetições de fêmeas. Os dados foram analisados como modelos mistos, considerando como efeitos fixos a restrição alimentar, a classe sexual e suas interações e como efeitos aleatórios os blocos e o erro. Os principais resultados foram que a restrição alimentar não afetou a taxa de passagem e turnover no rúmen (P>0,05), por outro lado influenciou a taxa de passagem no ceco e cólon (P<0,05). No segundo estudo buscou-se verificar o efeito da classe sexual e da restrição alimentar sobre a taxa de passagem de sólido e líquido em caprinos, assim como, estudar a associação entre a taxa de passagem e a digestibilidade dos nutrientes, comportamento ingestivo e distribuição das partículas no rúmenretículo. Foram utilizados os mesmos animais do primeiro estudo. O delineamento e a análise estatística dos dados foram iguais ao estudo anterior. Para mensuração da taxa de passagem foi usado o acetato de itérbio como indicador de sólido e para taxa de passagem de líquidos foi usado o Cr-EDTA. A restrição alimentar... / Two studies were conducted, the first aimed at study whether and how sex and feed restriction affects the rate of passage in goats fed with low fiber. We used 51 Saanen goats, 18 intact males, 18 castrated males and 15 females. These animals were randomly selected according to the type of feed restriction: no restriction (NR), moderate restriction (MR) and severe restriction (SR). The initial BW was of 30 kg and the trial finished when the goats NR reached 45 kg. Rate of passage in the rumen, caecum and colon was measure by the slaughter animals and neutral detergent fiber indigestible (NDFi) was adopted as the marker. Experimental design was randomized block in factorial design 3x3 with six repetitions of intact and castrated males and five repetitions for females. Data were analyzed as mixed models, considering as fixed effects feed restriction, sex and their interactions and blocks and error as random effects. The feed restriction unaffected the rate of passage in the rumen (P> 0.05), on the other hand influenced the passage rate (P <0.05) in the caecum and colon. The objective of the second study was evaluate effect of sex and feed restriction on passage rate of solid and liquid in goats, as well as studies the association between the rate of passage and digestibility of nutrients, feeding behavior and distribution of the particles in rumen-reticulum. The animals used were same those used in the first study. Experimental design and statistical analysis were also the same as in the previous study. To measure the rate of passage ytterbium acetate was used as solid marker and Cr-EDTA as liquid marker. Feed restriction did not affect the passage rate of liquid in all compartments, except in the jejunum. Both studies contributed to produce real values of passage rate of solid in the rumen and large intestine and the passage rate of liquid in different compartments of digestive tract... (Complete abstract click electronic access below)

Made available in DSpace on 2014-06-11T19:27:22Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-28Bitstream added on 2014-06-13T20:16:38Z : No. of bitstreams: 1 bruno_m_me_jabo_prot.pdf: 2616643 bytes, checksum: 97247720aae07e408b197a60a6613f6a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho avaliou-se o desempenho de reatores anaeróbios de fluxo ascendente com manta de lodo (UASB), em dois estágios, em escala de bancada (volumes de 20 L e 10 L, respectivamente), alimentados com água residuária do beneficiamento de café por via úmida, submetidos à quatro cargas orgânicas volumétricas (COV) de 5,76; 3,62; 3,86 e 2,16 kg DQO total (m3 d)-1 no primeiro reator, R1. As concentrações médias de DQO do afluente variaram de 8626 a 23041 mg L-1, e dos efluentes dos reatores 1 e 2, 1095 a 11506 mg L-1 e de 424 a 9030 mg L-1, respectivamente. As eficiências médias de remoção de DQO total e SST variaram de 66 a 98% e de 93 a 97% respectivamente, no sistema com reatores (UASB) em dois estágios. O teor de metano no biogás variou de 69 a 89% para o reator 1 e de 52 a 73% no reator 2. A produção volumétrica máxima de metano, 0,563 m3 CH4 (m3 reator d)-1 foi obtida com COV de 3,86 kg DQO (m3 d)-1 e TDH de 124 h. Os valores médios de pH variaram na faixa de 4,7 a 7,7 e 4,9 a 8,0 nos efluentes dos reatores 1 e 2, respectivamente. A concentração de ácidos voláteis totais manteve-se estável à níveis inferiores a 200 mg L-1 nos ensaios 2, 3 e 4. As concentrações médias de fenóis totais do afluente variaram de 79,7 a 97,4 mg L-1, e as eficiências médias de remoção no conjunto de reatores UASB em dois estágios variaram de 72 a 90%. / In this work it was evaluated the performance of two stage upflow anaerobic sludge blanquet (UASB), in lab scale, treating a liquid effluent from the coffee pulping, submitted to organic load rate of 5,76; 3,62; 3,86 and 2,16 kg COD (m3 d)-1 in the first reactor. The medium values of total COD affluent varied from 15439 to 23041 mg L-1, and in the effluent from the reactors 1and 2, 1095 to 11506 mg L-1, and 424 to 9030 mg L-1, respectively. The medium values of removal efficiences of total COD and TSS varied from 66 to 98% and 93 to 97%, respectively, in the system of treating with reactors UASB, in two stages. The content of methane varied from 69 to 89% in reactor 1 and 52 to 73% in reactor 2 . The maximum volumetric methane production 0,563 m3 CH4 (m3 reactor d)-1 was obtained with OLR of 3,86 kg COD (m3 d)-1 and HDT of 124 hours. Average pH values ranged from 4,7 to 7,7 and 4,9 to 8,0 for effluents of first and second reactors. Total volatile acid concentration was kept below 200 mg L-1. The medium values of total phenols of affluent ranged from 79,9 to 97,4 mg L-1, and the average removal efficiency ranged from 72 to 90% in the two stages upflow anaerobic sludge blanket (UASB).

Orientador: Izabelle Auxiliadora Molina Almeida Teixeira / Banca: Jane Maria Bertocco Ezequiel / Banca: Ricardo Andrade Reis / Banca: Mario Luiz Chizzotti / Banca: Antonello Cannas / Resumo: Foram realizados dois estudos, o primeiro teve como objetivo estudar se e como a classe sexual e a restrição alimentar afetam a taxa de passagem em caprinos alimentados com dieta com baixa fibra. Foram utilizados 51 caprinos da raça Saanen, sendo 18 machos não castrados, 18 machos castrados e 15 fêmeas, os quais foram sorteados segundo o tipo de restrição: ausente (RA), moderada (RM) e severa (RS). O experimento iniciou quando os animais atingiram em média 30 kg PC e finalizou quando os caprinos que receberam o tratamento RA atingiram peso corporal médio de 45 kg. Para mensuração da taxa de passagem, no rúmen, ceco e cólon, adotou-se a técnica de abate e foi utilizado como indicador interno a FDNi. Adotou-se o delineamento em blocos casualizado, em esquema fatorial 3x3 com seis repetições de machos não-castrados e castrados e cinco repetições de fêmeas. Os dados foram analisados como modelos mistos, considerando como efeitos fixos a restrição alimentar, a classe sexual e suas interações e como efeitos aleatórios os blocos e o erro. Os principais resultados foram que a restrição alimentar não afetou a taxa de passagem e turnover no rúmen (P>0,05), por outro lado influenciou a taxa de passagem no ceco e cólon (P<0,05). No segundo estudo buscou-se verificar o efeito da classe sexual e da restrição alimentar sobre a taxa de passagem de sólido e líquido em caprinos, assim como, estudar a associação entre a taxa de passagem e a digestibilidade dos nutrientes, comportamento ingestivo e distribuição das partículas no rúmenretículo. Foram utilizados os mesmos animais do primeiro estudo. O delineamento e a análise estatística dos dados foram iguais ao estudo anterior. Para mensuração da taxa de passagem foi usado o acetato de itérbio como indicador de sólido e para taxa de passagem de líquidos foi usado o Cr-EDTA. A restrição alimentar... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Two studies were conducted, the first aimed at study whether and how sex and feed restriction affects the rate of passage in goats fed with low fiber. We used 51 Saanen goats, 18 intact males, 18 castrated males and 15 females. These animals were randomly selected according to the type of feed restriction: no restriction (NR), moderate restriction (MR) and severe restriction (SR). The initial BW was of 30 kg and the trial finished when the goats NR reached 45 kg. Rate of passage in the rumen, caecum and colon was measure by the slaughter animals and neutral detergent fiber indigestible (NDFi) was adopted as the marker. Experimental design was randomized block in factorial design 3x3 with six repetitions of intact and castrated males and five repetitions for females. Data were analyzed as mixed models, considering as fixed effects feed restriction, sex and their interactions and blocks and error as random effects. The feed restriction unaffected the rate of passage in the rumen (P> 0.05), on the other hand influenced the passage rate (P <0.05) in the caecum and colon. The objective of the second study was evaluate effect of sex and feed restriction on passage rate of solid and liquid in goats, as well as studies the association between the rate of passage and digestibility of nutrients, feeding behavior and distribution of the particles in rumen-reticulum. The animals used were same those used in the first study. Experimental design and statistical analysis were also the same as in the previous study. To measure the rate of passage ytterbium acetate was used as solid marker and Cr-EDTA as liquid marker. Feed restriction did not affect the passage rate of liquid in all compartments, except in the jejunum. Both studies contributed to produce real values of passage rate of solid in the rumen and large intestine and the passage rate of liquid in different compartments of digestive tract... (Complete abstract click electronic access below) / Doutor

Orientador: Izabelle Auxiliadora Molina Almeida Teixeira / Coorientador: Telma Teresinha Berchielli / Banca: Ricardo Andrade Reis / Banca: Gustavo Rezende Siqueira / Banca: Alexandre Vaz Pires / Banca: Simone Gisele de Oliveira / Resumo: O objetivo deste estudo foi estimar a taxa de passagem em cabras leiteiras gestantes. O mesmo foi dividido em dois experimentos usando cabras multíparas, não lactantes, gestantes. O primeiro estudo foi realizado em 36 cabras, multíparas, com peso médio de 50,6 ± 7,7 kg, distribuídas nos tratamentos de acordo com a raça (Saanen e Alpina); tipo de prenhez (simples e gemelar) e período de gestação (80, 110 e 140 dias). O delineamento experimental foi completamente casualizado e teve como objetivo estimar a taxa de passagem de cabras leiteiras durante a gestação. O segundo estudo foi realizado em 49 cabras multíparas, não lactantes, com gestação gemelar e peso médio de 49.0 kg ± 8.9, distribuídas nos tratamentos de acordo com o período de prenhez (80,110,140 dias), tipo de restrição alimentar (sem restrição, moderada e severa), e raça (Saanen e Alpina). O delineamento experimental foi em blocos casualizados e o objetivo foi estimar a taxa de passagem em cabras leiteiras submetidas a resrição alimentar ao longo da prenhez. Para a estimativa da taxa de passagem foram fornecidos indicadores externos (itérbio para fase sólida e Cr-EDTA para fase líquida) e foi usada a metodologia do esvaziamento do trato digestório em animais abatidos para a coleta das amostras e foi mensurada a quantidade de gordura e o peso sorporal previo ao abate. A digestibilidade da MS e da MO aumenta em cabras com gestação gemelar no primeiro terço da prenhez e decresce ao final da gestação. Cabras com gestação simples apresentam maior digestibilidade da MS e do FDN na fase final da prenhez. Cabras leiterias gestantes não alteram a taxa de passagem dos sólidos no rúmen durante a prenhez. Cabras Saanen apresentaram maior taxa de diluição ruminal. A taxa de passagem dos sólidos em cabras gestantes submetidas a restrição alimentar varia entre 0.03 a 0.10/h... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objective of this study was to estimate passage rate in pregnancy goats. It was divided in three studies using goats multiparous, no milking, pregnancy. The first study was in 36 goats multiparous and mean weight was 50,6 kg ± 7,7 distributed in the treatments according breed (Saanen and Oberhasli), gestational age (80, 110, 140 days) and type of pregnancy (simples or twin). Design experimental was completely randomized and the objective was to estimate passage rate in milking goats during the pregnancy. The second study was in 49 goats multiparous, no milking, with twin pregnancy and mean weight 49.0 kg ± 8.9, distributed in the treatments according breed (Saanen and Oberhasli), gestational age (80, 110, 140 days) and nutritional restriction (no restriction, moderate and severe). Design experimental was in blocks randomized and the objective was to estimate passage rate in milking goats with nutritional restriction during pregnancy. For both studies were given orally external markers (ytterbium for solid phase and Cr- EDTA for liquid phase). Slaughter method was used and evacuation for sample collecting from gastro-intestinal tract and quantity of fat was measured. Digestibility assay was performed and the DMI was daily measured. Milking pregnancy goats not change ruminal passage rate during the pregnancy. DM, and organic matter increased in early pregnancy in twin pregnancy goats and decreased in late gestation. Simple pregnancy goats increased DM and NDF digestibility in late gestation. Pregnancy milking goats not changed passage rate of particles in the rumen. Saanen goats showed greater ruminal dilution rate. Passage rate in nutritional restriction goats range was 0,03 to 0,10 /h. Oberhasli breed with moderate restriction increased ruminal passage rate of solid phase in the secondthird of gestation. Passage rate alteration in pregnancy goats is associated to breed, nutritional level and gestational age / Doutor