Polyadenylation of pre-mRNAs is critical for efficient nuclear export, stability, and translation of the mature mRNAs, and thus for gene expression. The bulk of pre-mRNAs are processed by canonical nuclear poly(A) polymerase (PAPS). Both vertebrate and higher-plant genomes encode more than one isoform of this enzyme, and these are coexpressed in different tissues. However, in neither case is it known whether the isoforms fulfill different functions or polyadenylate distinct subsets of pre-mRNAs. This thesis shows that the three canonical nuclear PAPS isoforms in Arabidopsis are functionally specialized owing to their evolutionarily divergent C-terminal domains. A moderate loss-of-function mutant in PAPS1 leads to increase in floral organ size, whereas leaf size is reduced. A strong loss-of-function mutation causes a male gametophytic defect, whereas a weak allele leads to reduced leaf growth. By contrast, plants lacking both PAPS2 and PAPS4 function are viable with wild-type leaf growth. Polyadenylation of SMALL AUXIN UP RNA (SAUR) mRNAs depends specifically on PAPS1 function. The resulting reduction in SAUR activity in paps1 mutants contributes to their reduced leaf growth, providing a causal link between polyadenylation of specific pre-mRNAs by a particular PAPS isoform and plant growth. Additionally, opposite effects of PAPS1 on leaf and flower growth reflect the different identities of these organs. The overgrowth of paps1 mutant petals is due to increased recruitment of founder cells into early organ primordia whereas the reduced leaf size is due to an ectopic pathogen response. This constitutive immune response leads to increased resistance to the biotrophic oomycete Hyaloperonospora arabidopsidis and reflects activation of the salicylic acid-independent signalling pathway downstream of ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1)/PHYTOALEXIN DEFICIENT4 (PAD4). Immune responses are accompanied by intracellular redox changes. Consistent with this, the redox-status of the chloroplast is altered in paps1-1 mutants. The molecular effects of the paps1-1 mutation were analysed using an RNA sequencing approach that distinguishes between long- and short tailed mRNA. The results shown here suggest the existence of an additional layer of regulation in plants and possibly vertebrate gene expression, whereby the relative activities of canonical nuclear PAPS isoforms control de novo synthesized poly(A) tail length and hence expression of specific subsets of mRNAs. / Polyadenylierung von prä-mRNAs ist entscheidend für den Export aus dem Zellkern, die Stabilität und die Translation der reifen mRNAs und dadurch für die Genexpression. Der Großteil der mRNAs wird durch sogenannte canonische Poly(A) Polymerasen (cPAPS) prozessiert. Die Genome von sowohl Wirbeltieren als auch Pflanzen kodieren mehr als eine Isoform dieser Enzyme, welche gleichzeitig in verschiedenen Geweben exprimiert werden. Es ist jedoch kein Beispiel bekannt, das zeigt, ob die verschiedenen Isoformen unterschiedliche Funktionen einnehmen bzw. verschiedene Untergruppen von mRNAs polyadenylieren. Diese Arbeit zeigt, dass drei canonische PAPS Isoformen in Arabidopsis thaliana aufgrund ihrer evolutionär unterschiedlichen C-terminalen Domänen spezialisierte Funktionen haben. Eine schwache Verlust-Mutation im PAPS1 Gen bewirkt eine Vergrößerung der Blütenorgane, während die Blattgröße vermindert ist. Eine starke Verlust-Mutation bewirkt zusätzlich einen Defekt der männlichen Keimzellen. Im Gegenzug dazu sind Mutanten des PAPS2 oder PAPS4 Gens gesund und zeigen ein normales Wachstum. Polyadenylierung von SMALL AUXIN UP RNA (SAUR) mRNAs hängt spezifisch von der Funktion von PAPS1 ab. Die daraus entstehende Reduzierung der SAUR Aktivität in den paps1 Mutanten trägt zur Verringerung der Blattgröße bei und stellt eine kausale Verbindung zwischen Polyadenylierung spezifischer mRNAs durch bestimmte PAPS Isoformen und Pflanzenwachstum dar. Zusätzlich spiegeln die unterschiedlichen Effekte von PAPS1 auf Blüten und Blätter die Identitäten dieser Organe wieder. Das übermäßige Wachstum der mutanten Petalen beruht auf einer erhöhten Anzahl an Gründer-Zellen im frühen Primordium, wohingegen die verminderte Blattgröße auf eine ektopische Pathogen Antwort zurückzuführen ist. Diese konstitutive Immunantwort bewirkt eine erhöhte Resistenz der Mutanten gegenüber dem biotrophen Oomyceten Hyaloperonospora arabidopsidis und reflektiert die Aktivierung des Salizylsäure unabhängigen Signalweges von ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1)/PHYTOALEXIN DEFICIENT4 (PAD4). Immunantworten sind von Veränderungen des intrazellulären Redoxpotenzials gekennzeichnet. Damit übereinstimmend zeigen die Chloroplasten der paps1-1 Mutanten ein verändertes Redoxpotenzial. Zur genaueren Aufklärung der molekularen Effekte der paps1 1 mutation wurde eine RNA-Sequenzierungsmethode verwendet, die zwischen mRNAs mit langem oder kurzem Poly(A) Schwanz unterscheidet. Die Aktivitäten der verschiedenen canonischen PAPS Isoformen kontrollieren die Länge des neu synthetisierten poly(A) Schwanzes und damit die Expression spezifischer Untergruppen von mRNAs. Dadurch lassen die hier gezeigten Ergebnisse eine weitere Ebene der Genregulierung in Pflanzen, und möglicherweise auch in anderen Eukaryoten, vermuten.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2007. / Härtill 4 uppsatser.

Purpose: Ultrasonically measured intravesical prostatic protrusion may be a promising noninvasive method of assessing bladder outlet obstruction. Previous investigations of this technique focused on patients with acute urinary retention and symptomatic men identified in urology clinics, which may not reflect the distribution of intravesical prostatic protrusion in community dwelling men. Materials and Methods: In 2006 a total of 322 white men residing in Olmsted County, Minnesota underwent transrectal ultrasound examination which permitted direct measurement of intravesical prostatic protrusion. Cross-sectional associations between lower urinary tract symptoms/benign prostatic enlargement and intravesical prostatic protrusion were measured. Rapid increases in lower urinary tract symptoms/benign prostatic enlargement measures as predictors of severe intravesical prostatic protrusion were also assessed. Results: Overall 10% of these men had an intravesical prostatic protrusion of 10 mm or greater. Greater intravesical prostatic protrusion was weakly correlated with greater prostate volume (rs = 0.28), higher obstructive symptoms (rs = 0.18) and lower peak urinary flow rate (rs = -0.18). Men with the most rapidly growing prostate before intravesical prostatic protrusion measurement were 3 times more likely to have an intravesical prostatic protrusion of 10 mm or greater. Men with an intravesical prostatic protrusion of 10 mm or greater were more likely to use medications for lower urinary tract symptoms/benign prostatic enlargement compared to those with an intravesical prostatic protrusion less than 10 mm (adjusted OR 2.95, 95% CI 1.23-7.06). Conclusions: These population based data provide reference ranges for future studies of intravesical prostatic protrusion as a predictor of adverse urological outcomes. Intravesical prostatic protrusion is significantly correlated with greater prostate volume, higher obstructive symptoms and lower peak urinary flow rate, suggesting that it may have clinical usefulness in predicting the need for treatment.

No description available.

INTRODUÇÃO: A biometria hepática por ultra-som é freqüentemente solicitada na investigação diagnóstica de crianças, no entanto, há múltiplos métodos descritos, nenhum com aceitação consensual e carência de valores normais de referência. OBJETIVOS: Determinar o tamanho do fígado de crianças normais, entre 0 e 7 anos de idade, por ultra-sonografia e correlacionar os valores obtidos com as variáveis: idade, sexo, estatura, peso corporal e índice de massa corpórea (IMC). MÉTODOS: Entre 2003 e 2005 foram examinadas 584 crianças saudáveis, com idades entre 0 e 7 anos, aplicando-se método ultra-sonográfico padronizado. A hepatometria foi efetuada em planos de corte longitudinais, estabelecidos por linhas de orientação externas, associadas a reparos anatômicos extra e intra-hepáticos. Foram medidos: a) o diâmetro crânio-caudal do lobo hepático esquerdo, na linha médio-esternal (CCLME) e b) o diâmetro crânio-caudal da superfície posterior do lobo hepático direito, na linha hemiclavicular (CCPLHC). As crianças foram subdivididas em 11 grupos por faixa etária. Para o estudo de correlação foi utilizado o coeficiente de correlação de Pearson. O teste t de Student não-pareado foi aplicado na comparação das medidas entre os sexos e o teste de Bonferroni, para análise de variância das médias por faixa etária. Nomogramas em função da idade foram elaborados mediante modelos de regressão não-linear. RESULTADOS: As medidas hepáticas apresentaram correlação positiva e significante com a idade (r=0,75 para CCLME e 0,80 para CCPLHC), a estatura (r=0,80 para CCLME e 0,85 para CCPLHC) e o peso (r=0,74 para CCLME e 0,82 para CCPLHC), não havendo correlação com o IMC (r<0,11). Observou-se diferença significativa entre os sexos em 3 grupos etários, com valores maiores nos meninos. Observou-se aumento progressivo do tamanho do fígado na faixa etária estudada, proporcionalmente menor que o crescimento corporal e com padrão de crescimento diferenciado para cada um dos lobos: o lobo hepático esquerdo apresentou crescimento mais expressivo nos 3 primeiros anos de vida, enquanto que o direito apresentou crescimento gradual e progressivo dos 0 aos 7 anos. CONCLUSÕES: Os valores do tamanho do fígado de crianças normais, entre 0 e 7 anos de idade, foram determinados, mediante aplicação de técnica padronizada, verificando-se correlação positiva e significante entre o tamanho do fígado, a idade, a estatura e o peso corporal, não havendo correlação com o IMC. Não se observou diferença consistente das medidas hepáticas em relação ao sexo. Os nomogramas apresentados demonstram as variações normais do tamanho do fígado na população estudada, notando-se aumento progressivo com a idade, em menor proporção que o crescimento corporal e com padrão de crescimento diferenciado para cada lobo / INTRODUCTION: Several methods to determine sonographic liver size have been reported, none of them consensually accepted; moreover, there is a lack of normal reference values. OBJECTIVES:The proposal of this research is to determine sonographic liver size in normal newbors, infants, and children under 7 year of age and correlate obtained values to age, sex, body height, body weight and body mass index (BMI). METHODS: Between 2003 and 2005, 584 healthy children were examined with sonography. Liver measurements were performed on two standardized longitdinal seccional planes, defined by orientation external lines, related to, both, extra and intra-hepatic anatomic references. Two diameters were measured: a) left lobe cranio-caudal diameter, on mid-sternal line (CCMSL) and b) right lobe posterior surface cranio-caudal diameter, on midclavicular line (PCCMCL). Children were classified acconding to age and sorted in 11 groups. Statistical analysis: Pearsons correlation coefficient was used for correlation study. Unpaired Stutent t-test was applied for comparison of measures acconding to sex. Bonferroni test was used for variance analysis between the means at the different age groups. Nomograms of the liver size related to age were established by non-linear regression models. RESULTS: It was observed positive and significant correlation between liver measurements and age (r=0,75 for CCMSL and 0,80 for PCCMCL), body height (r=0,80 for CCMSL and 0,85 for PCCMCL), and body weight (r=0,74 for CCMSL and 0,82 for PCCMCL). No relevant correlation with BMI (r<0,11) was found. Significant difference between sexes were found in 3 age groups, with higher values in males. Liver size measurements showed progressive increase, proportionally lesser than body height and with a different growth pattern for each lobe: the left lobe presented major growth in the first 3 years of age, while the right lobe presented gradual and progressive growth from birth to 7 years of age. CONCLUSIONS: Liver size in normal newborns, infants, and children under 7 years of age was determined by sonographic standadized method. Data analysis revealed positive and significant correlation between liver size and age, as well as body height, and body weight. No relevant correlation was found between liver size and BMI, neither there was consistent difference of liver measures between sexes. Nomograms demonstrate normal variation range of liver size in the studied population, showing progressive increase acconding to age, proporcionally lesser than body height, and with a distinct growth pattern for each hepatic lobe

INTRODUÇÃO: A biometria hepática por ultra-som é freqüentemente solicitada na investigação diagnóstica de crianças, no entanto, há múltiplos métodos descritos, nenhum com aceitação consensual e carência de valores normais de referência. OBJETIVOS: Determinar o tamanho do fígado de crianças normais, entre 0 e 7 anos de idade, por ultra-sonografia e correlacionar os valores obtidos com as variáveis: idade, sexo, estatura, peso corporal e índice de massa corpórea (IMC). MÉTODOS: Entre 2003 e 2005 foram examinadas 584 crianças saudáveis, com idades entre 0 e 7 anos, aplicando-se método ultra-sonográfico padronizado. A hepatometria foi efetuada em planos de corte longitudinais, estabelecidos por linhas de orientação externas, associadas a reparos anatômicos extra e intra-hepáticos. Foram medidos: a) o diâmetro crânio-caudal do lobo hepático esquerdo, na linha médio-esternal (CCLME) e b) o diâmetro crânio-caudal da superfície posterior do lobo hepático direito, na linha hemiclavicular (CCPLHC). As crianças foram subdivididas em 11 grupos por faixa etária. Para o estudo de correlação foi utilizado o coeficiente de correlação de Pearson. O teste t de Student não-pareado foi aplicado na comparação das medidas entre os sexos e o teste de Bonferroni, para análise de variância das médias por faixa etária. Nomogramas em função da idade foram elaborados mediante modelos de regressão não-linear. RESULTADOS: As medidas hepáticas apresentaram correlação positiva e significante com a idade (r=0,75 para CCLME e 0,80 para CCPLHC), a estatura (r=0,80 para CCLME e 0,85 para CCPLHC) e o peso (r=0,74 para CCLME e 0,82 para CCPLHC), não havendo correlação com o IMC (r<0,11). Observou-se diferença significativa entre os sexos em 3 grupos etários, com valores maiores nos meninos. Observou-se aumento progressivo do tamanho do fígado na faixa etária estudada, proporcionalmente menor que o crescimento corporal e com padrão de crescimento diferenciado para cada um dos lobos: o lobo hepático esquerdo apresentou crescimento mais expressivo nos 3 primeiros anos de vida, enquanto que o direito apresentou crescimento gradual e progressivo dos 0 aos 7 anos. CONCLUSÕES: Os valores do tamanho do fígado de crianças normais, entre 0 e 7 anos de idade, foram determinados, mediante aplicação de técnica padronizada, verificando-se correlação positiva e significante entre o tamanho do fígado, a idade, a estatura e o peso corporal, não havendo correlação com o IMC. Não se observou diferença consistente das medidas hepáticas em relação ao sexo. Os nomogramas apresentados demonstram as variações normais do tamanho do fígado na população estudada, notando-se aumento progressivo com a idade, em menor proporção que o crescimento corporal e com padrão de crescimento diferenciado para cada lobo / INTRODUCTION: Several methods to determine sonographic liver size have been reported, none of them consensually accepted; moreover, there is a lack of normal reference values. OBJECTIVES:The proposal of this research is to determine sonographic liver size in normal newbors, infants, and children under 7 year of age and correlate obtained values to age, sex, body height, body weight and body mass index (BMI). METHODS: Between 2003 and 2005, 584 healthy children were examined with sonography. Liver measurements were performed on two standardized longitdinal seccional planes, defined by orientation external lines, related to, both, extra and intra-hepatic anatomic references. Two diameters were measured: a) left lobe cranio-caudal diameter, on mid-sternal line (CCMSL) and b) right lobe posterior surface cranio-caudal diameter, on midclavicular line (PCCMCL). Children were classified acconding to age and sorted in 11 groups. Statistical analysis: Pearsons correlation coefficient was used for correlation study. Unpaired Stutent t-test was applied for comparison of measures acconding to sex. Bonferroni test was used for variance analysis between the means at the different age groups. Nomograms of the liver size related to age were established by non-linear regression models. RESULTS: It was observed positive and significant correlation between liver measurements and age (r=0,75 for CCMSL and 0,80 for PCCMCL), body height (r=0,80 for CCMSL and 0,85 for PCCMCL), and body weight (r=0,74 for CCMSL and 0,82 for PCCMCL). No relevant correlation with BMI (r<0,11) was found. Significant difference between sexes were found in 3 age groups, with higher values in males. Liver size measurements showed progressive increase, proportionally lesser than body height and with a different growth pattern for each lobe: the left lobe presented major growth in the first 3 years of age, while the right lobe presented gradual and progressive growth from birth to 7 years of age. CONCLUSIONS: Liver size in normal newborns, infants, and children under 7 years of age was determined by sonographic standadized method. Data analysis revealed positive and significant correlation between liver size and age, as well as body height, and body weight. No relevant correlation was found between liver size and BMI, neither there was consistent difference of liver measures between sexes. Nomograms demonstrate normal variation range of liver size in the studied population, showing progressive increase acconding to age, proporcionally lesser than body height, and with a distinct growth pattern for each hepatic lobe

Metabolic depression is a ubiquitous characteristic of dormancy, allowing animals to survive off limited endogenous fuels supplies for extended periods of time. Metabolic depression is characterised by a complex set of physiological and biochemical changes (respiratory depression, bradycardia, hypophagia and cessation of renal function), in addition to a remarkable ability to prevent or minimise damage usually associated with such depressive changes (e.g. gut and muscle atrophy, renal failure and ischemic injuries). A coordinated shut-down of systems is essential to surviving long periods of dormancy, however, the mechanisms involved in regulating metabolic depression remain poorly understood. Aestivation, a period of dormancy that occurs in response to desiccating environments, provides an excellent model system for investigating the regulation of metabolic depression, because unlike other forms of dormancy such as hibernation, it is not confounded by changes in temperature or PO2 and thus represents a true intrinsic metabolic depression. The green striped burrowing frog, Cyclorana alboguttata, is an abundant species of burrowing frog inhabiting arid to semi-arid regions of Queensland and Northern New South Wales. During the dry season, C. alboguttata aestivates in an underground clay chamber; the aestivating period lasts on average for nine months a year, but in drought conditions may last for as long as several years. In recent years, C. alboguttata has become a well studied organism for investigating the physiological processes involved in aestivation, especially regarding muscle disuse atrophy and gut maintenance. Despite this, our understanding of this frog’s capacity to metabolically depress remains limited. The first aim of this study was to extend our current knowledge of metabolic depression during aestivation in C. alboguttata. C. alboguttata reduced whole animal metabolism by 82% within five weeks of aestivation. The effects of aestivation on mass specific in vitro tissue metabolic rate (VO2) varied among individual organs, with muscle and liver slices showing significant reductions in metabolism; kidney VO2 was elevated and there was no change in the VO2 of small intestine tissue slices. Organ size was also affected by aestivation, with significant reductions in the mass of all tissues, except the gastrocnemius. These reductions in organ size, combined with changes in mass specific VO2 of tissue slices, resulted in further energy savings to aestivating animals. Mitochondrial VO2 was significantly reduced during aestivation, by an average of 83%; in addition respiratory control ratios (RCRs), a measurement of mitochondrial coupling efficiency, significantly increased during aestivation, suggesting increased mitochondrial coupling efficiency. The second aim of this study was to investigate the potential role of the endogenous opioid system (EOS) and thyroid hormones in the regulation of metabolic depression in C. alboguttata. When incubated in the presence of opioid agonists, liver and muscle tissue slices from Cyclorana alboguttata underwent tissue- and agonist- specific metabolic depression. In most cases, the effect of opioid agonists on metabolism was more pronounced in tissue slices from aestivating animals. The delta (δ) opioid agonist DADLE was the most consistent in producing a metabolic depression, however the effect of DADLE on the metabolism of tissue slices was not reversible by the general opioid antagonist naloxone. Gene transcript levels for the δ-opioid receptor remained constant in the brain and in the muscle of aestivating C. alboguttata compared to controls. Opioid receptor XOR1 transcript levels also remained constant in the brain during aestivation compared to controls. There was a significant reduction in total thyroid hormone concentration in the plasma of C. alboguttata during aestivation, with thyroxine (T4) decreasing by 75% and an 84% reduction in triiodothyronine (T3). We also examined changes in gene expression of deiodinase 2 (D2) and deiodinase 3 (D3), the major activating and deactivating enzymes of thyroid hormones, respectively. There were no significant changes in gene expression of D2 in the brain or muscle, or of D3 in the brain; however there was a significant down-regulation of D3 transcripts in muscle tissue. In the liver, D2 was significantly down-regulated and D3 showed an increase in transcript levels that was approaching significance. During dormancy energy conservation is a key priority and as such dormant animals undergo a major metabolic depression to conserve their limited endogenous fuel supplies. At the same time, dormant animals are faced with the challenge of maintaining functional organs for immediate use upon arousal. In this study C. alboguttata appeared to selectively down- or up-regulating individual tissues, using both changes in metabolic rate and morphology. This strategy would allow maximal energy savings during aestivation without compromising organ functionality and survival at arousal. In addition, the frogs appeared to decrease rates of mitochondrial proton leak to a greater extent than ATP synthesis, consistent with an increase in mitochondrial coupling efficiency. Again, this ability to selectively down-regulate one process to a greater extent than another allows energy savings to be maximised without compromising processes essential for survival. C. alboguttata can survive in a dormant state for several years and it is hypothesised that these frogs become more energy efficient during aestivation. The regulation of metabolic depression still remains poorly understood. In this study the potential role of the EOS and thyroid hormones in regulating metabolic depression was investigated. The results of this study suggest the δ-opioid system may be responsible for the initiation of metabolic depression, while the mu (μ) and kappa (κ) opioid systems may be important during long term maintenance of aestivation. In addition, the EOS may exert its control over metabolism via both receptor and non-receptor mediated pathways. The significant down-regulation of total thyroid hormones, as well as the changes in gene expression of the thyroid deiodinases indicates thyroid hormones may also play a significant role in regulating metabolic depression. This suggests that the regulation of metabolic depression may involve several interacting systems, or perhaps a ‘systems cascade’.

No description available.

Foi realizado um experimento com a finalidade de apresentar um protocolo preciso, simples, rápido e de baixo custo para determinar os coeficientes de metabolizabilidade dos nutrientes e o valor energético das dietas. Para tal, determinaram-se os CMMS, CMPB e CMEB e EMAn através da comparação de diferentes metodologias de digestibilidade in vivo que incluem a utilização ou não de indicador Cr2O3 a 0,5% (coleta parcial) ou marcador Fe2O3 a 1% e a aplicação ou não de jejum (0, 4, 6 e 8 horas) pré-inicio de coleta e pós-período de alimentação. Também a duração do período de coleta foi testada (3 ou 5 dias). Foi estudado o efeito dos períodos de jejum sobre o tamanho dos órgãos digestivos. Foram utilizados 81 frangos de corte, machos, com 21 dias de idade, distribuídos individualmente em gaiolas de metabolismo, constituindo 9 tratamentos (TRAT) com 9 repetições em delineamento completamente casualizado. Em todos os TRAT houve 4 dias de adaptação à uma dieta única, com 3055 kcal EM/kg, à base de milho e farelo de soja. A água foi fornecida à vontade. Após o período de coleta, 5 aves por TRAT, que receberam jejum, foram pesadas e abatidas e o papo, moela+proventrículo, intestino delgado e cólon+ceco foram pesados, bem como o conteúdo presente em cada um. Através do aparecimento do marcador foi determinada a duração da passagem de digesta pelo TGI das aves. O tempo de passagem foi considerado como o tempo entre o fornecimento da dieta com óxido férrico e o início do aparecimento das excretas marcadas. Os coeficientes de metabolismo e a energia não diferiram significativamente na coleta total comparandose 3 ou 5 dias de coleta (P>0,05). O uso do marcador Fe2O3 e três dias de coleta, resultou em menor valor do CMPB (P<0,02) em relação à coleta total sem marcador. Na metodologia de coleta parcial com 5 dias de coleta, observou-se coeficientes de menor valor para todas as respostas (P<0,05), comparados a 3 dias de coleta. O uso da metodologia de coleta total resultou em maiores CMMS e CMPB (P<0,05) comparado à coleta parcial, em função de uma taxa incompleta de recuperação do Cr2O3 na excreta. Não foi observada influencia do jejum sobre o tamanho dos órgãos, indicando que em até 8 horas de jejum não há mudança no tamanho absoluto ou relativo dos mesmos. No entanto, o peso relativo do jejuno das aves submetidas a 4, 6 e 8 horas de jejum foi maior (P<0,03) do que o das aves sem jejum. O tempo médio de passagem da ração foi estimado em 228 minutos. Conclui-se que a coleta total de excretas, por um período de 3 dias, sem o uso de jejum, resulta no melhor método de avaliação de ingredientes e ração. / One experiment was conducted in order to define a reliable, easy to apply and non expensive protocol to determinate nutrient and energy metabolizability values of broiler chicken diets. For this purpose, metabolizability coefficients (MC) of dry matter (DM); crude protein (CP); gross energy (GE) and nitrogen-corrected apparent metabolizable energy (AMEn) were calculated through the comparison of different in vivo digestibility methodologies including the utilization of Cr2O3 (0,5%) as an indicator (partial collection) or Fe2O3 (1%) as a marker; fasting, prior to excreta collection and at the end of the feeding period (0, 4, 6 and 8 hours). Also, two excreta collection periods were tested (3 and 5 days). It was assessed the effect of fasting on digestive organs weight. Eighty one 21 days male broilers were distributed individually in metabolic cages used distributed in nine treatments (T) and nine replicates per T, in a completely randomized design. Birds were held in individual metabolism cages located in a controlledtemperature room. All T had a 4 day adaptation period to a single diet of 3055 kcal ME/kg, based on corn and soybean meal. Water was offered ad libitum. At the end of fasting, 5 birds per T that received fasting were sacrificed by cervical dislocation and weighed. Crop, proventriculus+gizzard, small intestine and the ceca+colon were removed and weighed individually as their contents as well. The passage time along broiler GIT was measured with ferric oxide as a marker. The passage time was taken as the time elapsed from time of marker administration to time of the first observation of droppings red color. Metabolism coefficients and energy were not significantly different between 3 and 5 days of total collection (P>0,05). CPMC was lower (P<0,02) for Fe2O3 utilization and 3 days excreta collection compared to the total collection. With the methodology of partial collection with 5 days of collection, it was observed the lowest values for all the responses (P<0,05), compared to 3 days collection period. The use of the total collection methodology produced the highest DMMC and CPMC (P<0,05) compared to partial collection, due to the incomplete recovery of the Cr2O3 from the excreta. No fasting influence was observed on the digestive organ sizes, indicating that until 8 hours of fasting no changes are observed in either relative or absolute organs weight. However, the relative jejunum weight of birds submitted to 4, 6 and 8 hours was higher (P<0,03) than those of birds under no fasting. The mean passage time of fed through broiler GIT was 228 minutes. It was conclude that total collection, during a 3 days period, without fasting utilization, is the best methodology for poultry ingredient and fed evaluation.

Foi realizado um experimento com a finalidade de apresentar um protocolo preciso, simples, rápido e de baixo custo para determinar os coeficientes de metabolizabilidade dos nutrientes e o valor energético das dietas. Para tal, determinaram-se os CMMS, CMPB e CMEB e EMAn através da comparação de diferentes metodologias de digestibilidade in vivo que incluem a utilização ou não de indicador Cr2O3 a 0,5% (coleta parcial) ou marcador Fe2O3 a 1% e a aplicação ou não de jejum (0, 4, 6 e 8 horas) pré-inicio de coleta e pós-período de alimentação. Também a duração do período de coleta foi testada (3 ou 5 dias). Foi estudado o efeito dos períodos de jejum sobre o tamanho dos órgãos digestivos. Foram utilizados 81 frangos de corte, machos, com 21 dias de idade, distribuídos individualmente em gaiolas de metabolismo, constituindo 9 tratamentos (TRAT) com 9 repetições em delineamento completamente casualizado. Em todos os TRAT houve 4 dias de adaptação à uma dieta única, com 3055 kcal EM/kg, à base de milho e farelo de soja. A água foi fornecida à vontade. Após o período de coleta, 5 aves por TRAT, que receberam jejum, foram pesadas e abatidas e o papo, moela+proventrículo, intestino delgado e cólon+ceco foram pesados, bem como o conteúdo presente em cada um. Através do aparecimento do marcador foi determinada a duração da passagem de digesta pelo TGI das aves. O tempo de passagem foi considerado como o tempo entre o fornecimento da dieta com óxido férrico e o início do aparecimento das excretas marcadas. Os coeficientes de metabolismo e a energia não diferiram significativamente na coleta total comparandose 3 ou 5 dias de coleta (P>0,05). O uso do marcador Fe2O3 e três dias de coleta, resultou em menor valor do CMPB (P<0,02) em relação à coleta total sem marcador. Na metodologia de coleta parcial com 5 dias de coleta, observou-se coeficientes de menor valor para todas as respostas (P<0,05), comparados a 3 dias de coleta. O uso da metodologia de coleta total resultou em maiores CMMS e CMPB (P<0,05) comparado à coleta parcial, em função de uma taxa incompleta de recuperação do Cr2O3 na excreta. Não foi observada influencia do jejum sobre o tamanho dos órgãos, indicando que em até 8 horas de jejum não há mudança no tamanho absoluto ou relativo dos mesmos. No entanto, o peso relativo do jejuno das aves submetidas a 4, 6 e 8 horas de jejum foi maior (P<0,03) do que o das aves sem jejum. O tempo médio de passagem da ração foi estimado em 228 minutos. Conclui-se que a coleta total de excretas, por um período de 3 dias, sem o uso de jejum, resulta no melhor método de avaliação de ingredientes e ração. / One experiment was conducted in order to define a reliable, easy to apply and non expensive protocol to determinate nutrient and energy metabolizability values of broiler chicken diets. For this purpose, metabolizability coefficients (MC) of dry matter (DM); crude protein (CP); gross energy (GE) and nitrogen-corrected apparent metabolizable energy (AMEn) were calculated through the comparison of different in vivo digestibility methodologies including the utilization of Cr2O3 (0,5%) as an indicator (partial collection) or Fe2O3 (1%) as a marker; fasting, prior to excreta collection and at the end of the feeding period (0, 4, 6 and 8 hours). Also, two excreta collection periods were tested (3 and 5 days). It was assessed the effect of fasting on digestive organs weight. Eighty one 21 days male broilers were distributed individually in metabolic cages used distributed in nine treatments (T) and nine replicates per T, in a completely randomized design. Birds were held in individual metabolism cages located in a controlledtemperature room. All T had a 4 day adaptation period to a single diet of 3055 kcal ME/kg, based on corn and soybean meal. Water was offered ad libitum. At the end of fasting, 5 birds per T that received fasting were sacrificed by cervical dislocation and weighed. Crop, proventriculus+gizzard, small intestine and the ceca+colon were removed and weighed individually as their contents as well. The passage time along broiler GIT was measured with ferric oxide as a marker. The passage time was taken as the time elapsed from time of marker administration to time of the first observation of droppings red color. Metabolism coefficients and energy were not significantly different between 3 and 5 days of total collection (P>0,05). CPMC was lower (P<0,02) for Fe2O3 utilization and 3 days excreta collection compared to the total collection. With the methodology of partial collection with 5 days of collection, it was observed the lowest values for all the responses (P<0,05), compared to 3 days collection period. The use of the total collection methodology produced the highest DMMC and CPMC (P<0,05) compared to partial collection, due to the incomplete recovery of the Cr2O3 from the excreta. No fasting influence was observed on the digestive organ sizes, indicating that until 8 hours of fasting no changes are observed in either relative or absolute organs weight. However, the relative jejunum weight of birds submitted to 4, 6 and 8 hours was higher (P<0,03) than those of birds under no fasting. The mean passage time of fed through broiler GIT was 228 minutes. It was conclude that total collection, during a 3 days period, without fasting utilization, is the best methodology for poultry ingredient and fed evaluation.