379 research outputs found

    Microbial activity in the gut of piglets: effect of fibre source and enzyme supplementation

    Get PDF
    Twenty four Duroc×Landrace male piglets, aged 21 days, were assigned to 1 of 4 experimental diets. Diets 1 and 2 contained 150 g kg−1 wheat bran and diets 3 and 4 contained 90 g kg−1 maize cobs as the major fibre source. All diets contained 480 g kg−1 wheat and 200 g kg−1 soybean meal. Diets 2 and 4 were supplemented with the following enzyme complex: 800 U/kg cellulase, 1800 U/kg glucanase and 2600 U/kg xylanase. The replacement of wheat bran by maize cobs increased the acetic (Pb0.05) and decreased the butyric acid production (Pb0.05) in the cecum. Piglets fed diets with maize cobs had lower (Pb0.05) levels of butyric acid in the colon than those fed wheat bran. The xylanolytic, pectinolytic and cellulolytic enzyme activities were higher (Pb0.05) in the cecum and colon of piglets fed the wheat bran based diets. The supplementation of the diet with the enzyme complex did not significantly affect the levels of short chain fatty acids formed in the small intestine and there was a non significant increase of the levels of acetic, propionic and butyric acids in the cecum and colon of piglets (Pb0.10). No interactions were present between fibre sources and enzyme addition. The results suggest that the enzyme supplementation of the diet did not bring significant benefits to the animals and that when maize cobs replaces wheat bran in diets it negatively affects butyric acid production and fibre-degrading enzyme activity in the hindgut of piglets. © 2007 Elsevier B.V. All rights reserved

    Effects of dietary fibre source and enzyme supplementation on faecal apparent digestibility, short chain fatty acid production and activity of bacterial enzymes in the gut of piglets

    Get PDF
    The effects of fibre source, either wheat bran (WB) or maize cobs (MC), and dietary exogenous enzymes (ES) on performance and digestive parameters of weaned piglets were studied in 24 Duroc×Landrace male piglets, weaned at 21 days of age. There were four treatments arranged factorially, with two sources of fibre (WB or MC) and two concentrations of ES (0 or 0.15 g/kg) that contained 800 U/kg of endo-1,4- -cellulase, 1800 U/kg of endo-1,3(4)- -d-glucanase and 2600 U/kg of endo-1,4- -xylanase. The digestibility of the neutral detergent fibre was higher (P<0.001) in diets containing WB and the digestibility of the acid detergent fibre increased with ES. Small intestine digesta contents (g/kg live weight) at slaughter were higher (P<0.01) in pigs fed MC than in pigs fed WB. Fibre source did not affect the amounts (mmol/l) of short chain fatty acids (SCFA) in the small intestine. However, replacement of WB by MC increased acetic acid and decreased butyric acid concentrations (P<0.05) in the caecum. In addition, pigs fed diets with MC as the major fibre source had lower (P<0.05) concentration of butyric acid in the colon than pigs fed diets with WB. Enzyme supplementation affected molar proportions of SCFA formed in the small intestine and tended to increase acetic acid, propionic acid and total SCFA concentrations in the colon of piglets fed WB (P<0.10). The xylanolytic and cellulolytic activities in the caecum and colon were higher (P<0.05) for piglets fed WB than for piglets fed MC. In conclusion, ES increased the digestibility of acid detergent fibre and neutral detergent fibre and the replacement of WB by MC reduced neutral detergent fibre and acid detergent fibre digestibility, caecal butyric acid production and hindgut activity of bacterial enzymes

    Microbial activity in the gut of piglets: effect of prebiotic and probiotic supplementation

    Get PDF
    Four groups of six 21 days-old piglets were used to evaluate the effect of a prebiotic or probiotic on the intestinal fermentative activity. In each group, piglets received one of the following diets: basal diet (C); basal diet supplemented with xylooligosaccharide (C-XOS); basal diet supplemented with Saccharomyces cerevisiae (C-SC); and basal diet supplemented with xylooligosaccharide and S. cerevisiae (C-XOS+SC). The short chain fatty acids in the colon of piglets were decreased with the inclusion of S. cerevisiae in the diet (Pb0.01). The xylanolytic activity was higher (Pb0.05) in the small intestine of piglets fed C-XOS+SC diet, but no significant differences were found in the caecum and colon. In the caecum contents, the cellulolytic activity was increased (Pb0.05) by the C-XOS and C-SC diets, but remained similar when the diet was supplemented with the two additives combined

    Effect of prebiotic or probiotic supplementation and ileo rectal anastomosis on intestinal morphology of weaned piglets

    Get PDF
    Forty eight 21 days old piglets were used to compare the effect of prebiotic or probiotic supplementation and ileo rectal anastomosis on the morphology of the small intestine. Half of the piglets were maintained intact and the other half was subjected to an ileo rectal anastomosis (IRA). Each group of piglets received one of the following diets: 1) basal diet (C), 2) basal diet supplemented with a Xylo-oligosaccharide (XOS), 3) basal diet supplemented with a Saccharomyces cerevisiae (SC) and 4) basal diet supplemented with XOS and SC. Villus height was greatest with XOS and with XOS + SC, only in the ileum, as compared to controls. In the duodenum, crypt width was highest in the control group, but no significant differences were found in the jejunum and ileum. The IRA piglets had longer villi in the jejunum and shorter villi in the ileum. The crypt depth was greater in the duodenum and in the ileum of IRA piglets. Villus height/crypt depth was lower in the duodenum and in the ileum, in the IRA piglets. In conclusion, the XOS, but not the SC, moderately modified the intestinal morphology. The IRA modified the intestinal villus and crypt architecture but its consequence on the absorption of nutrients needs to be investigated

    Perspetivas complementares de valorização do património em pedra em Almeida (Distrito da Guarda)

    Get PDF
    Pode considerar-se que a sua situação da vila de Almeida está enquadrada dentro dos princípios que definem a área temática "Cidade do presente" deste congresso, apresentando um processo de perda por efeito de mudanças estratégicas nacionais, sofrendo, desta forma, de problemas semelhantes. Esta situação promove processos de abandono que podem ter implicações negativas para as povoações e para o cuidado do património histórico, potencialmente com efeitos negativos no ambiente natural circundante. Neste trabalho, com base no caso de estudo de Almeida, pretendemos apresentar e discutir algumas perspetivas de valorização do património em pedra complementares dos aspetos mais históricos e artísticos. A comunicação irá incidir sobre questões de Engenharia, materiais geológicos, processos análogos de processos geológicos, assim como o desenvolvimento de organismos no património construído. Poderão desta forma definir-se atividades dinamizadoras do ensino de vários níveis e da atração turística que, na sua generalidade são menos afetadas pelos problemas de sazonalidade.Esta comunicação foi desenvolvida no âmbito de atividades financiadas por Fundos Europeus de Investimento através do FEDER/COMPETE/POCI - Programa de Competitividade e Internacionalização, e por Fundos Nacionais através da FCT – Fundação para a Ciência e a Tecnologia; financiamento concedido às unidades: - Lab2PT-Laboratório de Paisagens, Património e Território, projeto POCI-01-0145-FEDER-007528 e UID/AUR/04509/2013; - CITAB - Centro de Investigação e de Tecnologias Agro-Ambientais e Biologicas, projeto POCI-01-0145-FEDER-006958 e UID/AGR/04033/2013; - ISISE – ISISE – Instituto para a Sustentabilidade e Inovação em Engenharia Estrutural, projeto POCI-01-0145-FEDER-007633 e UID/ECI/04029/2013. Agradecimentos são igualmente devidos à Câmara Municipal de Almeida pela colaboração prestada na realização deste trabalho, nomeadamente pela criação de condições de alojamento aos investigadores e pela amável ajuda dos seus colaboradores, nomeadamente Dra. Paula Sousa, Eng.ª Lénia Fortunato e Diana Garcia. Agradecimentos também a Flávio Dias pela colaboração na realização do trabalho de campo

    Exploring the genomic diversity of black yeasts and relatives (Chaetothyriales, Ascomycota)

    Get PDF
    The order Chaetothyriales (Pezizomycotina, Ascomycetes) harbours obligatorily melanised fungi and includes numerous etiologic agents of chromoblastomycosis, phaeohyphomycosis and other diseases of vertebrate hosts. Diseases range from mild cutaneous to fatal cerebral or disseminated infections and affect humans and cold-blooded animals globally. In addition, Chaetothyriales comprise species with aquatic, rock-inhabiting, ant-associated, and mycoparasitic life-styles, as well as species that tolerate toxic compounds, suggesting a high degree of versatile extremotolerance. To understand their biology and divergent niche occupation, we sequenced and annotated a set of 23 genomes of main the human opportunists within the Chaetothyriales as well as related environmental species. Our analyses included fungi with diverse life-styles, namely opportunistic pathogens and closely related saprobes, to identify genomic adaptations related to pathogenesis. Furthermore, ecological preferences of Chaetothyriales were analysed, in conjuncture with the order-level phylogeny based on conserved ribosomal genes. General characteristics, phylogenomic relationships, transposable elements, sex-related genes, protein family evolution, genes related to protein degradation (MEROPS), carbohydrate-active enzymes (CAZymes), melanin synthesis and secondary metabolism were investigated and compared between species. Genome assemblies varied from 25.81 Mb (Capronia coronata) to 43.03 Mb (Cladophialophora immunda). The bantiana-clade contained the highest number of predicted genes (12,817 on average) as well as larger genomes. We found a low content of mobile elements, with DNA transposons from Tc1/Mariner superfamily being the most abundant across analysed species. Additionally, we identified a reduction of carbohydrate degrading enzymes, specifically many of the Glycosyl Hydrolase (GH) class, while most of the Pectin Lyase (PL) genes were lost in etiological agents of chromoblastomycosis and phaeohyphomycosis. An expansion was found in protein degrading peptidase enzyme families S12 (serine-type D-Ala-D-Ala carboxypeptidases) and M38 (isoaspartyl dipeptidases). Based on genomic information, a wide range of abilities of melanin biosynthesis was revealed; genes related to metabolically distinct DHN, DOPA and pyomelanin pathways were identified. The MAT (MAting Type) locus and other sex-related genes were recognized in all 23 black fungi. Members of the asexual genera Fonsecaea and Cladophialophora appear to be heterothallic with a single copy of either MAT-1-1 or MAT-1-2 in each individual. All Capronia species are homothallic as both MAT1-1 and MAT 1-2 genes were found in each single genome. The genomic synteny of the MAT-locus flanking genes (SLA2-APN2-COX13) is not conserved in black fungi as is commonly observed in Eurotiomycetes, indicating a unique genomic context for MAT in those species. The heterokaryon (het) genes expansion associated with the low selective pressure at the MAT-locus suggests that a parasexual cycle may play an important role in generating diversity among those fungi
    corecore