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1

Gindri, Marcelo. "Digesta passage rate in Saanen goats : a meta-analytic approach /." Jaboticabal, 2020. http://hdl.handle.net/11449/192760.

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Orientador: Izabelle Auxiliadora Molina de Almeida Teixeira
Resumo: A taxa de passagem da digesta (kp) em ruminantes é a passagem fracionada da digesta por hora, isto é /h. A kp é um processo complexo e dinâmico e afeta a digestão dos alimentos e o impacto ambiental da produção animal. Neste estudo, objetivamos compreender os fatores relacionados à kp em todo o trato gastrointestinal (TGI) de caprinos em crescimento e caprinos alimentados com níveis de alimentação e propor equações para prever kp de partículas e solutos no reticulo-rúmen. Para isso, utilizamos um banco de dados de dois estudos com caprinos Saanen, que foi dividido em dois bancos de dados diferentes: o banco de dados Crescimento foi composto por registros individuais de machos castrados (n = 36), fêmeas (n = 34) e machos intactos (n = 33) alimentados ad libitum e abatidos aos 15, 22, 30, 37 e 45 kg de peso corporal (PC); e, o banco de dados níveis de alimentação foi composto por registros individuais de machos castrados (n = 38), fêmeas (n = 33) e machos intactos (n = 36) alimentados ad libitum, 75 ou 50% ad libitum durante 109 ± 10 dias . Nossos resultados demonstraram que a taxa de passagem da digesta tem respostas diferentes, quando avaliada em cabras em crescimento ou cabras alimentadas com níveis de alimentação a longo prazo. O kp de partículas no reticulo-rúmen não foi afetado pelo crescimento animal ou pelo nível de alimentação. No entanto, o kp de partículas no reticulo-rúmen e o kp de partículas e solutos no intestino grosso demonstraram ser positivamente relacionados... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The digesta passage rate (kp) in ruminants is a fractional passage of digesta per hour, i.e. /h. The kp is a very complex and dynamic process and affects feed digestion and the environmental impact of livestock. In this study, we aimed to understand the factors related to kp in the whole gastrointestinal tract (GIT) of growing goats and goats fed with feeding levels and propose equations for predicting kp of particles and solutes in reticulorumen. For that, we used a database from two studies with Saanen goats that was split into two different databases: database Growth was composed by individual records of castrated males (n = 36), females (n = 34), and intact males (n = 33) fed ad libitum and slaughtered at 15, 22, 30, 37, and 45 kg body weight (BW); and, database Feeding Levels was composed by individual records of castrated males (n = 38), females (n = 33), and intact males (n = 36) fed ad libitum, 75 or 50% of ad libitum over 109 ± 10 days. Our results demonstrated digesta passage rate had different responses whether evaluated in growing goats or goats fed with feeding levels over long-term. Reticulorumen kp of particles was not affected by growth or feeding level. However, reticulorumen kp of particles and large intestines kp of particles and solutes were positively related among them in growing goats. Reticulorumen kp of solutes decreased with aging followed by increasing on reticulorumen capacity and reducing on dry matter (DM) intake level and chewing investment (che... (Complete abstract click electronic access below)
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2

Linton, Jennifer Anne Voelker. "Effects of dietary forage characteristics on digesta passage rate in dairy cows." Diss., Connect to online resource - MSU authorized users, 2006.

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3

Herron, Fiona Michelle. "A study of digesta passage in rabbits and ringtail possums using markers and models." Thesis, The University of Sydney, 2002. http://hdl.handle.net/2123/483.

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The common ringtail possum (Pseudocheirus peregrinus), a member of the family Pseudocheiridae, is an arboreal folivorous marsupial that feeds predominantly on Eucalyptus foliage. Contrary to the expectation that small body size would inhibit utilisation of a diet containing such high levels of lignified fibre because of relatively low gut volume to body mass ratios and relatively high mass-specific metabolic rates and nutrient requirements (Hume 1999), the ringtail possum is able to survive solely on a diet of Eucalyptus foliage. The rabbit (Oryctolagus cuniculus) is a terrestrial herbivore and is a member of the family Leporidae that feeds predominantly on grasses. The rabbit was proposed as a digesta flow model for the ringtail possum since both are caecotrophic (periodically re-ingest caecal contents) and both are proposed to exhibit a colonic separation mechanism (CSM) where fluids and small, easily digested particles are preferentially returned to the caecum. The rabbit is of value for the modelling process since it is more accessible for experimental manipulation than the ringtail possum. This study investigated a proposal to use digesta passage through the gastrointestinal tract (GIT) of the rabbit as a model of digesta passage for the ringtail possum on the basis that both are caecotrophic caecum fermenters. A number of potential problems were identified with this proposal and investigation of these problems formed the basis for the research described in this thesis. Two main areas were identified as being potentially problematic: 1) fundamental flaws with the particulate markers used in digesta rate of passage studies; and 2) differences in animal behaviour and natural diet between the two subject species which suggested different digestive strategies and hence different patterns of digesta flow through the GIT. The proposed digesta passage markers were lanthanide metals (Dy, Tm, Eu and Yb) attached to either fibrous particles (1200 - 600�m) or formalin-fixed rumen bacteria (20 � 0.2�m). These markers were shown to not be of the assumed size classes and the extent of lanthanide metal binding differed between the four metals used. An effect due to method of dosing was also observed. The findings of marker inconsistencies caused major limitation to model development and further research is necessary to clarify these markers. The proposal to use digesta flow in the rabbit GIT as a model for digesta flow in the ringtail possum was shown to be idealistic due to the differences in anatomy and behaviour observed between the two herbivores. Laboratory observations, time series analysis and compartmental modelling confirmed the differences between the animals. This study showed: 1) the GIT of the rabbit was more complex both anatomically and functionally than that of the ringtail possum; 2) behaviour affecting digesta passage of the rabbit and ringtail were different and; 3) compartmental models confirmed the anatomical and behavioural findings. Digesta passage in the rabbit could not be modelled mathematically using data on digesta passage due to complexities of the system. In contrast, a basic model was constructed for digesta passage in the ringtail possum. On the basis of these findings, the research hypothesis "that digesta passage in rabbits is similar to that in ringtail possums" was rejected.
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4

Herron, Fiona Michelle. "A study of digesta passage in rabbits and ringtail possums using markers and models." University of Sydney. Biology, 2002. http://hdl.handle.net/2123/483.

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The common ringtail possum (Pseudocheirus peregrinus), a member of the family Pseudocheiridae, is an arboreal folivorous marsupial that feeds predominantly on Eucalyptus foliage. Contrary to the expectation that small body size would inhibit utilisation of a diet containing such high levels of lignified fibre because of relatively low gut volume to body mass ratios and relatively high mass-specific metabolic rates and nutrient requirements (Hume 1999), the ringtail possum is able to survive solely on a diet of Eucalyptus foliage. The rabbit (Oryctolagus cuniculus) is a terrestrial herbivore and is a member of the family Leporidae that feeds predominantly on grasses. The rabbit was proposed as a digesta flow model for the ringtail possum since both are caecotrophic (periodically re-ingest caecal contents) and both are proposed to exhibit a colonic separation mechanism (CSM) where fluids and small, easily digested particles are preferentially returned to the caecum. The rabbit is of value for the modelling process since it is more accessible for experimental manipulation than the ringtail possum. This study investigated a proposal to use digesta passage through the gastrointestinal tract (GIT) of the rabbit as a model of digesta passage for the ringtail possum on the basis that both are caecotrophic caecum fermenters. A number of potential problems were identified with this proposal and investigation of these problems formed the basis for the research described in this thesis. Two main areas were identified as being potentially problematic: 1) fundamental flaws with the particulate markers used in digesta rate of passage studies; and 2) differences in animal behaviour and natural diet between the two subject species which suggested different digestive strategies and hence different patterns of digesta flow through the GIT. The proposed digesta passage markers were lanthanide metals (Dy, Tm, Eu and Yb) attached to either fibrous particles (1200 - 600�m) or formalin-fixed rumen bacteria (20 � 0.2�m). These markers were shown to not be of the assumed size classes and the extent of lanthanide metal binding differed between the four metals used. An effect due to method of dosing was also observed. The findings of marker inconsistencies caused major limitation to model development and further research is necessary to clarify these markers. The proposal to use digesta flow in the rabbit GIT as a model for digesta flow in the ringtail possum was shown to be idealistic due to the differences in anatomy and behaviour observed between the two herbivores. Laboratory observations, time series analysis and compartmental modelling confirmed the differences between the animals. This study showed: 1) the GIT of the rabbit was more complex both anatomically and functionally than that of the ringtail possum; 2) behaviour affecting digesta passage of the rabbit and ringtail were different and; 3) compartmental models confirmed the anatomical and behavioural findings. Digesta passage in the rabbit could not be modelled mathematically using data on digesta passage due to complexities of the system. In contrast, a basic model was constructed for digesta passage in the ringtail possum. On the basis of these findings, the research hypothesis "that digesta passage in rabbits is similar to that in ringtail possums" was rejected.
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5

Lickel, Laura Evelyn. "Intake, apparent digestibility, and digesta passage in leopard tortoises (Geochelone pardalis) fed a complete, extruded feed." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/480.

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The influence of feeding juvenile female leopard tortoises (Geochelone pardalis, n=18) a commercially available, complete, extruded feed three (3) or seven days (7) per week on dry matter and digestible energy intake, apparent digestibility of dry matter, organic matter, gross energy and fiber fractions, animal body weight and measurements, digesta transit time, rate of passage, and indigestible fill was evaluated. Both feeding frequencies are commonly practiced with captive tortoises. When fed 7 compared to 3 days per week, dry matter and digestible energy intake was greater. Tortoises gained more g BW, but not when adjusted per kg initial BW. When fed 7 compared to 3 days per week, tortoises grew more in plastron width (PW) and carapace height (CH), but not midline straight carapace length (MSCL), and grew more in calculated shell volume (i.e., a calculated estimate of shell volume using MSCL, PW, and CH), with a higher calculated body condition index (BCI). Providing short fasts (i.e., feeding 3 compared to 7 days per week) may be useful in slowing tortoise growth when animals are provided food ad libitum. In general, ad libitum feeding, especially of a highly digestible extruded feed, is not recommended for captive juvenile G. pardalis, especially when offered food daily. With two data points (detected as outliers) removed due to low fecal output (and resulting unrealistically high apparent digestibility of all nutrients analyzed) of two animals when fed 3 days per week, apparent digestibility of cellulose in tortoises fed 7 (n=18) compared to 3 (n=16) days per week was lower, but no differences were detected in DM, OM, GE, or any other fiber fractions analyzed. Transit time (TT1) was shorter and indigestible fill was higher in tortoises (n=18) fed 7 compared to 3 days per week, regardless of percent Cr marker recovered. With four animals removed due to <50% Cr marker recovery, tortoises fed 7 compared to 3 days per week exhibited shorter mean retention time (RGIT), with no differences in digesta transit or indigestible fill. Longer digesta retention when food availability included short periods of fasting may have allowed tortoises to extract more energy from cellulose.
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6

Magadlela, Andrew Mtutuzeli. "An evaluation of n-alkanes as markers to estimate dry matter intake, diet selection and solid digesta passage rates in ruminants." Thesis, University of Edinburgh, 2001. http://hdl.handle.net/1842/28523.

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Study 1 (exp 1, 2, and 3) assessed the use of alkanes for estimating diet composition and intake in lambs. In exp 1, 36 lambs at 30% and 45% of projected mature sizes were used in a factorial design with 2 breeds (Suffolk and Scottish Blackface), two sexes (male and female) and three feed treatments [pelleted lucerne (Medicago sativa) or pelleted ryegrass (Lolium spp) alone or both as a choice] to compare alkane-derived estimates of dry matter intake (DMI) and selected diet with direct measurements. In exp 2, to assess diurnal variation in n-alkane concentration in the gut, 6 restricted and 6 ad libitum fed lambs at 45% mature size were used in a split-plot design to compare the ratios of the amount of dotriacontane (C32) to tritriacontane (C33) in the faeces collected at 4 hourly intervals over a 24 hour period. In exp 3, to evaluate the efficacy of dosing once-daily (cf. twice-daily) with C32, 6 once-daily and 6 twice-daily dosed lambs were used in a split-plot design to compare faecal alkane ratios of C33 to C32. Exp 1 suggested general agreement between measured quantities and those estimated using the alkane technique However, at 30% mature size, for the lambs fed on grass only, dry matter intake was slightly overestimated and for those fed on lucerne and grass as a choice, dry matter intake of lucerne was underestimated. Exp 2 indicated that the ratio of the concentration of C33:C32 in the faeces was not affected by sampling time and thus no diurnal variation irrespective of whether the lambs were restricted or ad libitum fed. Experiment 3 suggested no difference in the ratios of the concentrations of C33:C32 between the two dosing strategies until the fifth day of dosing. Study II used the alkane pair of C36 and C35 to compare the voluntary dry matter intake of Brachiaria decumbens by 8 dry cows, averaging 301 kg liveweight and 8 lactating Criollo cows averaging 320 kg liveweight during the wet season and 8 lactating cows averaging 300 kg liveweight and 7 dry cows, averaging 289 kg liveweight during the dry season of Bolivia. Results suggested that this alkane pair can be used to estimate the dry matter of intake of tropical forages, but if the concentrations of C35 are very low the accuracy of the estimate may be compromised.
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7

Al, Kindi Amal [Verfasser]. "Influence of quebracho tannin extract and activated charcoal on nutrient intake and digestibility, digesta passage, nitrogen balance, and quality of faecal excreta in goats / Amal Al Kindi." Kassel : Universitätsbibliothek Kassel, 2015. http://d-nb.info/1073893243/34.

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8

Ribeiro, Rodrigo Corn?lio de Oliveira. "Digestibilidade ruminal obtida com digesta omasal, perfil de degrada??o obtido por esvaziamento ruminal e estimativa da fra??o digest?vel da fibra em detergente neutro de volumosos para bovinos." UFVJM, 2013. http://acervo.ufvjm.edu.br:8080/jspui/handle/1/402.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG)
Instituto Nacional de Ci?ncia e Tecnologia de Ci?ncia Animal (INCT-CA)
Um experimento foi realizado com o objetivo de estimar o consumo, a digestibilidade total e as taxas de digest?o (kd) e de passagem (kp) ruminal dos nutrientes de dietas constitu?das exclusivamente por volumosos. Avaliaram-se tamb?m algumas equa??es para predizer a digestibilidade da fibra destes alimentos para bovinos de corte. Foram utilizados cinco bovinos mesti?os Holand?s x Zebu, machos n?o castrados, fistulados no r?men, com peso corporal (PC) m?dio inicial de 458,5 ? 32,5 kg, distribu?dos em delineamento experimental em quadrado latino 5 x 5 balanceado para efeito residual. O experimento foi constitu?do de cinco per?odos experimentais, com dura??o de dezesseis dias cada um, sendo sete dias destinados ? adapta??o dos animais ?s dietas e os outros nove para a realiza??o das coletas. As dietas experimentais foram constitu?das de cinco volumosos, sendo utilizadas as silagens de milho (SM, Zea mays, L.), de capim-elefante (SCE, Pennisetum purpureum Schum) e de capim-braqui?ria (SCB, Brachiaria decumbens), a cana-de-a??car in natura (CA, Saccharum officinarum L.) e o feno de capim-tifton 85 (TF85, Cynodon spp.). Utilizou-se a mistura de ureia/sulfato de am?nio na propor??o de 9:1 para manter as dietas isoproteicas (11% de PB). Os dados foram analisados utilizando o procedimento MIXED do SAS (vers?o 9.1), utilizando-se o teste de Tukey e 0,05 como n?vel cr?tico de probabilidade para o erro tipo I. O consumo de mat?ria seca (CMS) foi maior (P<0,05) para os animais alimentados com SM quando comparado aos animais que receberam CA. Maiores (P<0,05) valores para o consumo de FDNcp foram observados para os animais alimentados com SM, SCB, SCE e FT85. N?o houve diferen?a (P>0,05) para os coeficientes de digestibilidade aparente da MS, MO, PB e CNF entre os volumosos avaliados. A digestibilidade da FDNcp foi maior (P<0,05) para os animais alimentados com SCB, SCE e FT85 em rela??o aos alimentados com CA. Maior (P<0,05) valor para o coeficiente de digestibilidade ruminal (CDR) da FDNcp foi observado para os animais que receberam SCB, SCE e FT85 em rela??o aos que consumiram CA. N?o houve diferen?a (P>0,05) para o Pool (kg/dia) e para a kp (h-1) da FDNcp entre os diferentes volumosos avaliados. A efici?ncia microbiana (g/kg NDT) foi maior (P<0,05) para os animais alimentados com SCB (147,08 g/kg NDT). Houve intera??o (P<0,05) entre os efeitos de tratamento e tempo de mensura??o do pH ruminal. Os valores de pH no l?quido ruminal apresentaram comportamento quadr?tico em fun??o do tempo e os valores m?ximos de 6,72; 7,10; 7,06 e 6,92 foram estimados nos tempos de 9,45; 10,99; 11,13 e 12,00 horas ap?s a alimenta??o para as dietas contendo SM, SCB, SCE, e FT85, respectivamente. Os valores de pH para CA apresentaram comportamento linear decrescente em fun??o do tempo. Conclui-se que o uso exclusivo de volumosos tropicais nas dietas de bovinos, com exce??o da cana-de-a??car in natura, proporcionam consumo e digestibilidades dos nutrientes satisfat?rios, visto que dietas com 11% de PB atendem as exig?ncias m?nimas de compostos nitrogenados para os microrganismos ruminais maximizarem a digest?o da fibra em detergente neutro.
Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013.
ABSTRACT This experiment was conducted to estimate the nutrient intake, total digestibility, ruminal digestion (kd) and passage (kp) rates of nutrient from diets containing only forages. Equations to predict the fiber digestibility of feed for beef cattle were also evaluated. There had been used five crossbred Holstein x Zebu steers, fistulated in rumen, with body weight (BW) ranging 458.5 ? 32.5 kg, distributed in Latin square experimental design 5 x 5 balanced for residual effects. The experiment consisted of five experimental periods, lasting sixteen days each, being seven days for adaptation animals to the diets and the other nine to perform the collection. The experimental diets were composed of five forages, being maize silage - SM (Zea mays, L.), elephant grass - SCE (Pennisetum purpureum Schum); Brachiaria grass silage - SCB (Brachiariadecumbens); the sugar cane in natura - CA (Saccharum officinarum L.); and Tifton hay 85 - FT85 (Cynodon spp.). A mixture of urea/ammonium sulfate was used in a 9:1 ratio to maintain diets isonitrogenated (11% CP). Data were analyzed using the MIXED procedure of SAS (version 9.1), using the Tukey test and 0.05 as the critical level of probability for Type I error. The dry matter intake (CMS) was higher (P <0.05) for animals fed with SM when compared to animals receiving CA. Higher (P <0.05) values for the FDNcp intake were observed for animals fed with SM, SCB, SCE and FT85. There was no difference (P> 0.05) for apparent digestibility coefficients of MS, MO, PB and CNF among forages evaluated. The digestibility of FDNcp was higher (P <0.05) for animals fed with SCB, SCE and FT85 than those fed with CA. Greater (P <0.05) value for ruminal digestibility (CDR) of FDNcp was observed for animals receiving SCB, SCE and FT85 compared to those fed CA. No differences were observed (P> 0.05) for Pool (kg/day) and kp (h-1) from FDNcp among the different forage evaluated. The microbial efficiency (g/kg NDT) was higher (P <0.05) in animals fed with SCB (147.08g/kg NDT). There was an interaction (P <0.05) between the effects of treatment and time of measurement of ruminal pH. The pH of the rumen fluid showed a quadratic function of time and the maximum values of 6.72, 7.10, 7.06 and 6.92 being estimated at the times of 9.45, 10.99, 11.13 and 12.00 hours after feeding for the diets containing SM, SCB, SCE, and FT85, respectively. The pH values for CA linearly decreased in function of time. We conclude that the exclusive use of tropical forages in the diets of cattle, with the exception of sugar cane in natura, provide a satisfactory intake of digestible nutrients, whereas diets with 11% CP meet the minimum requirements for nitrogen compounds for ruminal microorganisms maximize the digestion of neutral detergent fiber.
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Rivera, Astrid Rivera [UNESP]. "Estudo da taxa de passagem de cabras em gestação." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/104073.

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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
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10

Rivera, Astrid Rivera. "Estudo da taxa de passagem de cabras em gestação /." Jaboticabal, 2013. http://hdl.handle.net/11449/104073.

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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
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11

Bompadre, Thiago Francisco Ventoso [UNESP]. "Avaliação de modelos empíricos para determinação da taxa de passagem de caprinos em crescimento." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/136108.

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A taxa de passagem (kp) está associada a uma série de fatores interligados como por exemplo a ingestão, digestão e aproveitamento do alimento. O rúmen e o retículo são os principais segmentos do trato gastrintestinal para a digestão da fibra. Levando em consideração a importância da kp na nutrição de ruminantes, alguns estudos vêm concentrando seus esforços em equacioná-la. Na literatura existem diversos modelos para predição da kp em ruminantes, mas poucos modelos geram predições para caprinos. Nesse sentido o presente estudo visa avaliar modelos para estimativa da kp ruminal de caprinos. O banco de dados utilizado para avaliar os modelos da literatura provem de dois estudos com caprinos em crescimento entre 15 e 45 kg de peso corporal, totalizando 102 animais com consumo à vontade. Foi utilizada a metodologia de evacuação ruminal em animais abatidos e os marcadores considerados para as medidas de kp foram o itérbio (marcador externo de fase sólida) e a FDN indigestível (marcador interno da fase sólida). Foram avaliados cinco modelos que predizem a kp, sendo estes provenientes de publicações em revistas de grande impacto científico. A avaliação destes modelos foi conduzida utilizando o conceito da regressão do resíduo (observado menos predito) pelo predito centralizado. Considerando a kp obtida a partir do itérbio, nenhum modelo da literatura se adequou aos dados observados no presente estudo. Por outro lado, quando a kp foi obtida com dados de FDN indigestível (FDNi), o modelo desenvolvido por Krizsan et al. (2010) foi acurado (viés médio, P = 0,82) e não apresentou erro sistemático no intervalo de variação das predições (viés linear, P = 0,45). Foi realizado teste de covariância para identificar variáveis que poderiam melhorar a adequação dos modelos. O modelo teórico proposto por Vieira et al. (2008) após a incorporação da ingestão de FDNi no modelo, apresentou viés médio...
The passage rate (kp) is related to several factors, such as intake, digestion and nutrient absorption. Fiber digestion is greater in the reticulorumen segment. Considering the importance of kp in ruminant nutrition, some studies have been developing models to predict kp. In the literature, there are many models to predict kp in ruminants, but few models consider exclusively goats. Thus, this study aimed to evaluate most widely used models to determine kp in growing goats. The database used to evaluate the literature models derived from two studies with Saanen goats of different growth stages between 15 and 45 kg of body weight. A total of 102 goats fed ad libitum were used. The studies used the ruminal evacuation technique in slaughtered animals. The markers used were Ytterbium (external marker of solid phase) and indigestible NDF (internal marker of solid phase). Five kp models published between 1960 and 2013 were evaluated. The evaluation of the literature models was conducted using the regression of residual (observed minus predicted) on centered predicted values. Considering the model evaluation for Ytterbium in the observed data, none of the models tested fit well in this database. On the other hand, when the models were evaluated using the indigestible NDF database, the model developed by Krizsan et al. (2010) was accurate (mean bias, P = 0.82) and did not present systematic error in the prediction variance (linear bias, P = 0.45). A covariance analysis were performed for identifying variables to improve the adequacy of the models. The theoretical model developed by Vieira et al (2008) after integrating iNDF intake, showed mean bias (P = 0.42) and linear bias (P = 0.75). In conclusion, in ruminal evacuation technique studies using iNDF as marker, the models developed by Vieira et al. (2008) adjusted by iNDF intake and Krizsan et al. (2010) could provide a reliable prediction of kp for growing goats
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12

Bompadre, Thiago Francisco Ventoso. "Avaliação de modelos empíricos para determinação da taxa de passagem de caprinos em crescimento /." Jaboticabal, 2015. http://hdl.handle.net/11449/136108.

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Abstract:
Orientador: Izabelle Auxiliadora Molina de Almeida Teixeira
Coorientador: Rafael Fernandes Leite
Coorientador: Normand R. St-Pierre
Banca: José Gilson Louzada Regadas Filho
Banca: Carla Joice Härter
Resumo: A taxa de passagem (kp) está associada a uma série de fatores interligados como por exemplo a ingestão, digestão e aproveitamento do alimento. O rúmen e o retículo são os principais segmentos do trato gastrintestinal para a digestão da fibra. Levando em consideração a importância da kp na nutrição de ruminantes, alguns estudos vêm concentrando seus esforços em equacioná-la. Na literatura existem diversos modelos para predição da kp em ruminantes, mas poucos modelos geram predições para caprinos. Nesse sentido o presente estudo visa avaliar modelos para estimativa da kp ruminal de caprinos. O banco de dados utilizado para avaliar os modelos da literatura provem de dois estudos com caprinos em crescimento entre 15 e 45 kg de peso corporal, totalizando 102 animais com consumo à vontade. Foi utilizada a metodologia de evacuação ruminal em animais abatidos e os marcadores considerados para as medidas de kp foram o itérbio (marcador externo de fase sólida) e a FDN indigestível (marcador interno da fase sólida). Foram avaliados cinco modelos que predizem a kp, sendo estes provenientes de publicações em revistas de grande impacto científico. A avaliação destes modelos foi conduzida utilizando o conceito da regressão do resíduo (observado menos predito) pelo predito centralizado. Considerando a kp obtida a partir do itérbio, nenhum modelo da literatura se adequou aos dados observados no presente estudo. Por outro lado, quando a kp foi obtida com dados de FDN indigestível (FDNi), o modelo desenvolvido por Krizsan et al. (2010) foi acurado (viés médio, P = 0,82) e não apresentou erro sistemático no intervalo de variação das predições (viés linear, P = 0,45). Foi realizado teste de covariância para identificar variáveis que poderiam melhorar a adequação dos modelos. O modelo teórico proposto por Vieira et al. (2008) após a incorporação da ingestão de FDNi no modelo, apresentou viés médio...
Abstract: The passage rate (kp) is related to several factors, such as intake, digestion and nutrient absorption. Fiber digestion is greater in the reticulorumen segment. Considering the importance of kp in ruminant nutrition, some studies have been developing models to predict kp. In the literature, there are many models to predict kp in ruminants, but few models consider exclusively goats. Thus, this study aimed to evaluate most widely used models to determine kp in growing goats. The database used to evaluate the literature models derived from two studies with Saanen goats of different growth stages between 15 and 45 kg of body weight. A total of 102 goats fed ad libitum were used. The studies used the ruminal evacuation technique in slaughtered animals. The markers used were Ytterbium (external marker of solid phase) and indigestible NDF (internal marker of solid phase). Five kp models published between 1960 and 2013 were evaluated. The evaluation of the literature models was conducted using the regression of residual (observed minus predicted) on centered predicted values. Considering the model evaluation for Ytterbium in the observed data, none of the models tested fit well in this database. On the other hand, when the models were evaluated using the indigestible NDF database, the model developed by Krizsan et al. (2010) was accurate (mean bias, P = 0.82) and did not present systematic error in the prediction variance (linear bias, P = 0.45). A covariance analysis were performed for identifying variables to improve the adequacy of the models. The theoretical model developed by Vieira et al (2008) after integrating iNDF intake, showed mean bias (P = 0.42) and linear bias (P = 0.75). In conclusion, in ruminal evacuation technique studies using iNDF as marker, the models developed by Vieira et al. (2008) adjusted by iNDF intake and Krizsan et al. (2010) could provide a reliable prediction of kp for growing goats
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13

Silva, Simone Pedro da [UNESP]. "Taxa de passagem em caprinos submetidos ou não à restrição alimentar." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/105319.

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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)
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14

Silva, Simone Pedro da. "Taxa de passagem em caprinos submetidos ou não à restrição alimentar /." Jaboticabal, 2013. http://hdl.handle.net/11449/105319.

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Abstract:
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)
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15

Giannarelli, Sylvie. "Validation de modèles cellulaires issus du tractus digestif : la lignée IEC-6 pour l'étude de l'adaptation aux AINS et à l'éthanol au cours des passages successifs : mise au point d'un modèle de cellules musculaires lisses isolées." Aix-Marseille 3, 1996. http://www.theses.fr/1996AIX30015.

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Divers travaux suggerent qu'un lien existe entre certains troubles gastrointestinaux, tels que les etats gastritiques ou certains dysfonctionnements de la motricite, et le vieillissement du tractus digestif. Dans la maladie ulcereuse serait implique un deficit de la cytoprotection adaptative. En quete d'un modele cellulaire adapte a la fois aux etudes sur le vieillissement et sur la cytoprotection, nous montrons a partir de donnees histologiques et biochimiques que les cellules de la lignee iec-6 etablie, sans transformation ni cancerisation, a partir des cellules intestinales de rats nouveau-nes i) subissent une evolution reproductible au cours des passages successifs ii) fournissent une reponse trophique aux faibles concentrations d'ains et d'ethanol iii) cette reponse est adaptative ; elle est concomitante a une augmentation de la synthese des pg et du taux d'ampc probablement via une stimulation des proteines gs. L'adaptation varie en fonction de la densite cellulaire, des temps de passage et du milieu de culture: en milieu standard, seuls les passages medians s'adaptent ; apres privation en serum, les cellules repondent quel que soit le passage. Une moindre expression des recepteurs membranaires ne pourra que partiellement expliquer le deficit d'adaptation ; le routage intracellulaire de l'information semble dependre des temps de passage et du milieu de culture. Ainsi, le modele iec-6 s'avere un bon modele d'etude in vitro i) de certains mecanismes de senescence ii) des reponses a certains agents agresseurs iii) des reponses aux conditions environnementales. Nous validons, aussi, la mise au point d'un modele de cellules musculaires isolees de colon humain. Il est fonctionnel, stimulable par un agoniste muscarinique et relaxable par l'atropine. Ce modele devrait permettre de mieux cerner la part revenant a la cellule musculaire lisse elle meme dans l'ensemble des mecanismes physiologiques et physiopathologiques de la motricite colique
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16

Luick, Bret R. "Digesta passage rates in the rat." Thesis, 1990. http://hdl.handle.net/1957/27133.

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The movements of digestion markers in the gut of the rat were investigated and the results of the investigation are reported in two manuscripts. The objective of the first study was to determine the influence of particle size of dietary wheat bran, chosen as a representative insoluble fiber, on the mean retention time (MRT) of digesta in the rat. The study design included a control group to detect the influence of particle size of digestion marker on the observed retention times. Additionally, a comparison was made between bran and the soluble fiber pectin. Both the soluble cobalt EDTA (Co EDTA) and insoluble chromium mordanted bran (CrMB), of two size ranges were administered to 4 groups of rats fed a semi-purified diet supplemented with wheat bran or pectin (10% dilution). Bran size and particulate marker size were large/large, large/small, small/small and pectin/small for the 4 groups. Mean retention times for CrMB were significantly longer in the pectin than the bran supplemented groups. Differences were not significantly different within the bran supplemented group. No significant differences were found between the rate of passage of CrMB and Co EDTA in any group. The second study was designed to identify pooling of markers in the rat gut. A mathematical model was developed as a system of equations which predicted the marker distribution along the gut following dosing. The model assumed that two pools, the stomach and cecum, were kinetically recognizable in the rat. The predicted distribution of CrMB and Co EDTA was compared to in vivo distribution at 4 h intervals by sequential termination and dissection of the animals. The smaller particle bran had a longer MRT in the cecum and a shorter MRT in the proximal colon. Total MRT to the mid-colon was similar in all bran supplemented groups. Pectin fed animals had significantly enlarged gut organs which explained the slower movement of marker in these animals. The cecum was found to delay the transit of marker from the small intestine to the proximal colon as much as 2.1 h. This delay resulted in the gut appearing as a single pool overall and therefore led the model to overpredict the initial rate of appearance of marker distal to the cecum. A streamlined system was developed to digest the fecal samples in preparation for atomic absorption spectroscopy, the method used to quantify digestion marker recovery. The development of the method is discussed and supporting data are presented on the reproducibility and limits of the method.
Graduation date: 1991
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