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Chlodulfe, Tchibozo Sélidji Vital, Dossa Luc Hippolyte, Houndonougbo Fédéric, Koura Bossima Ivan et Houinato Benjamin Marcel. « Effets De L’incorporation Du Son De Maïs A Différents Doses Sur Les Performances De Croissance Des Lapereaux Et La Rentabilité De L’élevage ». European Scientific Journal, ESJ 13, no 24 (31 août 2017) : 473. http://dx.doi.org/10.19044/esj.2017.v13n24p473.
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This study was conducted to evaluate the performance of rabbits fed with rations containing corn bran at different levels of incorporation. Three rations, R5, R11 and R16, were formulated with incorporation rates of corn bran of 5.5%, 11% and 16.5%, respectively. Ninety young rabbits of 5 weeks of age were used for the experiments. The fattening study lasted 8 weeks and that of digestibility lasted for 1 week. The findings showed that the ration with 5.5% maize bran showed the best growth performances (18 g/d) with the highest digestibility values of dry matter (67%) and cellulose (97%). The ration with 16.5% corn bran yields 17 g / d with a better digestibility of the crude protein (97%) and the highest efficiency index (2.40). The ration with 11% maize bran is the most expensive (1395 Fcfa/kg) and has intermediate characteristics to that of the other two. The ration R could be used by rabbit farmers in urban and peri-urban areas to improve animal zootechnical performances. Future studies should be focused on the digestive use of different nutrients in rabbits through an in vivo study.
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Rakotoarimanana, Vonjison, et Michel Grouzis. « Effets à court terme du feu et du pâturage sur la qualité fourragère d’une savane àHeteropogon contortus du sud-ouest de Madagascar ». Revue d’élevage et de médecine vétérinaire des pays tropicaux 61, no 2 (1 février 2008) : 81. http://dx.doi.org/10.19182/remvt.10003.
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Une étude expérimentale sur le rôle du feu et du pâturage a été conduite dans la région de Sakaraha (sud-ouest de Madagascar). L’objectif a été d’évaluer les effets conjugués ou séparés du feu appliqué selon différentes modalités (sans feu, feu précoce, feu tardif) et du pâturage (non pâturé, pâturé) sur l’évolution de la qualité fourragère d’une savane à Heteropogon contortus et Poupartia caffra. L’appréciation de cette qualité fourragère a été réalisée en étudiant la valeur pastorale et la valeur fourragère. Une étude diachronique a permis de montrer (a) une augmentation de la valeur pastorale par les feux et une diminution de celle-ci par le pâturage, (b) une augmentation des teneurs de l’ensemble des paramètres de la valeur fourragère des herbages en fonction des feux et du pâturage. La valeur pastorale et la valeur fourragère de cette savane sont deux indices qui évoluent généralement dans le même sens sous l’influence du feu.
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Malthête, Jacques. « Un feu d'artifice improvisé ? Les effets pyrotechniques chez Méliès ». 1895. Mille huit cent quatre-vingt-quinze, no 39 (1 février 2003) : 61–72. http://dx.doi.org/10.4000/1895.3082.
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Yang, Wei, Min Zhou, Lishi Yan, Xin Ju et Liangzhi Li. « Diversity of Paenibacillus sp. LLZ1 cellulase and its improved enzyme activity and stability in the ionic liquid 1-ethyl-3-methylimidazolium diethyl phosphate ». BioResources 14, no 2 (27 février 2019) : 3132–45. http://dx.doi.org/10.15376/biores.14.2.3132-3145.
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The stability of cellulase in the presence of ionic liquids (ILs) is pivotal for the in situ saccharification of cellulose. This study investigated the effects of various carbon sources on the cellulase production of Paenibacillus sp. LLZ1. The results showed that the activities of both the total cellulase and endoglucanase induced by microcrystalline cellulose were higher than those induced by other examined carbon sources. Simultaneously, a zymography analysis revealed the presence of seven protein bands (carboxymethylcelluloses 3, 4 and 6 through 10) with endoglucanase activity when MCC was used as the carbon source for culturing Paenibacillus sp. LLZ1. The endoglucanase induced by MCC showed stability in a 25% solids 1-ethyl-3-methylimidazolium diethylphosphate ([Emim]DEP) solution. Furthermore, the addition of metal ions and surfactants increased the endoglucanase activity in the [Emim]DEP solution, where 0.5 mM of Fe2+ and 0.1% of polysorbate (PSM 60) led to 11% and 29% increases in filter paper activity, respectively. Finally, three types of biomass (MCC, bagasse cellulose, and bagasse) were used as raw materials for in situ enzymatic hydrolysis when involved 5% [Emim]DEP and 0.1% polyoxyethylene (60) sorbitan monostearate (PSM 60). Fourier-transform infrared spectroscopy and specific surface area measurements were used to explain the effects of PSM 60 on the hydrolysis efficiency of these three biomasses.
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Mawussi, Ayité Claude, Florence Tagodoe et Koffi Kpotchou. « Les travailleuses du sexe à Lomé face à la Covid-19 ». Cahiers du Genre 75, no 2 (17 janvier 2024) : 227–55. http://dx.doi.org/10.3917/cdge.075.0227.
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La pandémie de la Covid-19 et la mesure du couvre-feu ont beaucoup fragilisé les travailleuses du sexe à Lomé. Le présent article questionne les effets de la crise sanitaire sur leur activité. Il montre que le couvre-feu a dégradé leur travail et les a rendues économiquement plus vulnérables. Dans ce contexte, la plupart d’entre elles, même si elles en connaissent les conséquences, continuent d’avoir des comportements à risque, alors que d’autres nient l’existence de la maladie. Pour certaines, l’activité de prostitution a migré sur les réseaux sociaux, alors que d’autres ont enclenché un processus de reconversion professionnelle ou continuent uniquement de voir leurs clients réguliers. Ces stratégies sont fonction des ressources de chacune.
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Santoni, P. A., J. H. Balbi et J. L. Dupuy. « Dynamic modelling of upslope fire growth ». International Journal of Wildland Fire 9, no 4 (1999) : 285. http://dx.doi.org/10.1071/wf00004.
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A two-dimensional non-stationary model of fire spread including slope effects is proposed. The numerical study of this model allows us to predict the rate of spread, the fire front perimeter and the temperature distribution for a fire spreading across a fuel bed under slope conditions. The numerical results are compared with success to experimental data generated from two laboratory point-ignition fire experiments which were conducted on dehydrated Pinus pinaster litter with slopes of 20 and 30°. Résumé Nous proposons un modèle bidimensionnel évolutif de propagation de feu prenant en compte les effets de la pente. L’étude numérique du modèle présenté ici nous permet de prédire la vitesse de propagation, le perimètre du front de feu ainsi que la distribution de température pour un feu se propageant dans une litière en présence d’une pente. Les résultats numériques que nous obtenons sont comparés avec succés aux données expérimentales issues de deux expériences qui furent réaliseés dans une litière de pin maritime avec un allumage ponctuel pour des pentes de 20 et 30 degrés.
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Yedmel, Memel S. Ch, Adjumane A. Kadio, Olivier J. Hardy, N’Guessan François Kouame et Nicolas S. Barbier. « Impact du feu sur la structure et la composition floristique d’un peuplement forestier de Côte d’Ivoire et interaction avec les traitements sylvicoles ». Canadian Journal of Forest Research 40, no 10 (octobre 2010) : 1904–13. http://dx.doi.org/10.1139/x10-117.
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La dynamique structurale et floristique des forêts tropicales humides en réponse aux perturbations reste très méconnue, en dépit des problématiques actuelles de stockage de carbone et de conservation de la biodiversité. Le dispositif de la Téné (Côte d’Ivoire) est un peuplement forestier suivi depuis 1978, afin d’étudier à long terme la dynamique des espèces à potentiel commercial. En 1983, il a été accidentellement parcouru par le feu, et plus de 65 % de la surface totale a été atteinte. L’objectif de cette étude est d’évaluer l’impact des modalités sylvicoles combinées au passage du feu sur la structure et la composition floristique du peuplement. Les variations structurales et floristiques ont été testées respectivement à l’aide d’un simple modèle d’ANCOVA et d’une ordination. Les résultats obtenus montrent que l’impact du feu, en termes de surface brûlée, de structure et de composition floristique, a été significativement accru par les perturbations induites par les traitements sylvicoles. Les modalités sylvicoles supposées bénéfiques à l’accroissement des espèces à potentiel commercial peuvent accroître la susceptibilité aux feux et entraîner à long terme des effets majeurs sur la structure et la composition floristique du peuplement.
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Huang, Hai, Yuantao Hu, Hui Zhang, Shilin Cao et Xiaojuan Ma. « Limitations on the protective action of MgSO4 for cellulose during kraft pulp oxygen delignification ». BioResources 16, no 1 (7 janvier 2021) : 1438–52. http://dx.doi.org/10.15376/biores.16.1.1438-1452.
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Magnesium sulfate (MgSO4) is the most widely used protector for alleviating the effects that metal ions have on cellulose degradation. However, the efficiency of MgSO4 is limited by the oxygen delignification conditions. This work discusses the factors influencing MgSO4 efficiency in terms of cellulose protection and delignification. The type and concentration of metal ions, delignification rate, additions order, and mixing degree of MgSO4 should affect the cellulose degradation during oxygen delignification in the presence of MgSO4. The most adverse effects on cellulose are observed with Mn2+ and Fe2+ ions followed by Cu2+ and Fe3+. MgSO4 addition can diminish such negative effects; however the protection becomes reduced in the presence of higher concentrations of metal ions. In addition, the optimum MgSO4 application level is closely dependent on the delignification rate and metal ions concentration. Adding MgSO4 is optional for pulps with trace metal ions at relatively low delignification levels, but it is essential for pulps with concentrated metal ions or when the oxygen delignification rate is relatively high. More simply, when the added MgSO4 is thoroughly mixed with the pulp before the addition of NaOH, it exhibits a prominent effect on cellulose protection.
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Souza, Dênia Oliveira de, Cirano José Ulhoa, Weslane Justina da Silva, Denise Russi Rodrigues, Nadielli Pereira Bonifácio, Fabiana Ramos dos Santos, Fabiano Guimarães Silva et Cibele Silva Minafra. « Evaluation of the Addition of Humicola Grisea Cellulase to Broiler Chicken Rations for a 21-Day Period ». Poultry 2, no 4 (13 novembre 2023) : 463–74. http://dx.doi.org/10.3390/poultry2040035.
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This study aimed to evaluate the addition of liquid cellulose, produced by Humicola grisea, in 21-day-old broiler chickens’ diets. The treatments comprised control rations of corn and soybean meal and rations to which 500 mL/t and 1000 mL/t of cellulase were added. A total of 180 male broiler chickens were used, distributed in a completely randomized design, with three treatments and six replicates. Broiler chicken performance was monitored during the period from 1 to 21 days old. Significant effects were detected for digestibility only between four and seven days old, when a reduced dry matter nitrogen intake was recorded, and for nitrogen digestibility in the broilers fed cellulase-supplemented rations at a dose of 1000 m/L. Among the analyzed digestive organs, only the biometrics of the large intestine were affected significantly at seven days old. The absolute weights of the liver and pancreas and the activities of amylase, alkaline phosphatase, and transaminases were not affected significantly, indicating that cellulase did not affect the metabolism of these organs. No significant effect was detected in the serum for electrolytes, total protein, or alkaline phosphatase. So, the addition of liquid cellulase produced by Humicola grisea did not affect performance and metabolism in 21-day-old broiler chickens.
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Cemin, Henrique S., Mike D. Tokach, Steve S. Dritz, Jason C. Woodworth, Joel M. DeRouchey, Robert D. Goodband et Matt W. Allerson. « PSV-9 Effects of insoluble fiber source (cellulose or distillers dried grains with solubles) on growth performance of nursery pigs ». Journal of Animal Science 97, Supplement_2 (juillet 2019) : 193–94. http://dx.doi.org/10.1093/jas/skz122.341.
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Abstract A total of 3,171 pigs (PIC 327×L42; initially 5.8 kg) were used in a 39-d study. Treatments were arranged in a 2 × 2 factorial with 0 or 1% cellulose (Arbocel, J. Rettenmaier USA, Schoolcraft, MI) and distillers dried grains with solubles (DDGS; 0 or 5% in phase 1 and 0 or 15% in phase 2). Dietary phases 1 and 2 were offered from d 0 to 10 and 10 to 25, respectively. From d 25 to 39, pigs received a common diet with 25% DDGS. Pens were blocked by weight and allotted to treatments in a randomized complete block design. Experimental unit was two pens (66 pigs) sharing a fence-line feeder with 12 replicates per treatment. Data were analyzed with the GLIMMIX procedure of SAS with block as random effect. From d 0 to 25 and d 0 to 39, there was an interaction (P < 0.05) between cellulose and DDGS for ADG. Pigs fed diets with both DDGS and cellulose had lower ADG than those fed diets without DDGS, with pigs fed diets with DDGS without the addition of cellulose being intermediate. From d 25 to 39, there was a tendency (P = 0.080) for an interaction for ADFI. Pigs previously fed diets without DDGS and with cellulose had higher ADFI than those fed diets with DDGS and cellulose, and pigs previously fed diets without cellulose had similar ADFI regardless of DDGS inclusion. There was a tendency for an interaction (P = 0.070) for pig removals. Adding cellulose to diets without DDGS numerically decreased pig removals, but the inclusion of cellulose to diets with DDGS resulted in increased pig removals. In summary, adding fiber to the diet as cellulose or DDGS resulted in a less pig removals; however, adding both cellulose and DDGS decreased ADG and ADFI.
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Cott, Peter A., Barry A. Zajdlik, Kelly J. Bourassa, Marc Lange et Andrew M. Gordon. « Effects of Forest Fire on Young-of-the-year Northern Pike, Esox lucius, in the Northwest Territories ». Canadian Field-Naturalist 124, no 2 (1 avril 2010) : 104. http://dx.doi.org/10.22621/cfn.v124i2.1046.
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In 1998, a forest fire burned 58% of the forested shoreline surrounding Tibbitt Lake, Northwest Territories, including riparian vegetation used by Northern Pike (Esox lucius) as spawning habitat. This presented an opportunity to investigate the effects that habitat disturbance from a natural forest fire had on young-of-the-year (Y-O-Y) Northern Pike. Pike fry were collected from three burned and three unburned sites around Tibbitt Lake in 1999 (the first post-fire spawning season) and again in 2001. Differences in size and relative abundance were evaluated between sites. Y-O-Y Northern Pike were significantly larger at the unburned sites (P<0.01) and the relative abundance of Y-O-Y Northern Pike increased significantly at burned sites (alpha=0.1; P<0.07) following re-vegetation two years post fire. These differences may be due to fire-induced changes in physical habitat or food availability. Forest fires decrease the density of riparian vegetation, which likely provides better spawning and rearing habitat for Northern Pike in the long-term.En 1998, un feu de forêt a brûlé 58% de la rive boisée entourant le lac Tibbitt, situé dans les Territoires du Nord-Ouest, y compris la végétation riveraine utilisé par le grand brochet (Esox lucius) comme habitat de fraie. Cet événement a présenté une occasion pour étudier les effets causés par un feu de foret sur l'habitat de jeunes de l'année du grand brochet. Les jeunes brochets ont été recueillis sur trois sites brûlées et trois sites non brûlés autour du lac Tibbitt en 1999 (la première année de fraie après le feu de forêt) et à nouveau en 2001. La différence de grandeur et l'abondance relative des poissons ont été analysés entre les différents sites. Les jeunes grands brochets aux sites non-atteints par le feu étaient considérablement plus grands (P < 0,01) que ceux aux sites brulés. Les sites brulés, subissant une rapide revégétation dans les deux années après le feu, ont augmenté en abondance relative de jeunes grands brochets (alpha = 0,1, P < 0,07). Ces différences peuvent être dues aux changements induits par le feu sur l'aspect physique de l'habitat ou sur la disponibilité de nourriture. Les incendies de forêt réduisent la densité de la végétation riveraine, qui fournit probablement de meilleure habitat de fraie et d'alevinage pour le grand brochet à long terme.
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May, Thomas. « EFFETS CONTRASTÉS DES PRÉLÈVEMENTS DE BOIS SUR LA VÉGÉTATION DE FORÊT SÈCHE EN ZONE FRONTALIÈRE DOMINICO-HAÏTIENNE : COMMENT LES INTERPRÉTER ? » BOIS & ; FORETS DES TROPIQUES 326, no 326 (18 décembre 2015) : 3. http://dx.doi.org/10.19182/bft2015.326.a31279.
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En Haïti, le bois de feu et le charbon végétal sont des sources importantes d’énergie domestique, et le prélèvement de bois à des fins énergétiques repré- sente un facteur de dégradation de la forêt sèche, en plus du parcours d’ani- maux domestiques (chèvres et vaches). En République dominicaine limitrophe, tandis qu’il y a trois décennies la situa- tion était similaire, les conditions ont aujourd’hui changé et les forêts sèches montrent des signes de régénération. Dans l’extrême sud de la ligne de fron- tière entre les deux pays, près d’Anse- à-Pitre et Pedernales, l’opportunité se présente de comparer l’état de la forêt sèche des deux côtés, dans des condi- tions géologiques et climatiques très semblables. Notre étude montre que le couvert des individus arbustifs et arborés et la hauteur des arbres sont plus élevés en République dominicaine, tandis que le nombre d’individus multicaules issus de régénération végétative est plus élevé en Haïti. En général, la composition spé- cifique est similaire des deux côtés de la frontière, mais des différences significa- tives apparaissent dans les fréquences et les valeurs d’abondance-dominance. Acacia scleroxylon, Amyris elemifera, Bursera simarouba, Capparis ferruginea et Guaiacum sanctum sont plus fréquents en République dominicaine, et Acacia macracantha, Senna atomaria, Phyllosty- lon brasiliense et les deux cactacées Pilo- socereus polygonus et Opuntia sp. sont au contraire plus fréquents en Haïti. Ces différences sont imputables à l’autécolo- gie des espèces (ex. : capacité de colo- niser les terrains perturbés, capacité de régénération végétative) plutôt qu’à des préférences dans leur utilisation comme bois de feu ou de charbon.
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Overton, P. D., N. Furlonger, J. M. Beety, J. Chakraborty, J. A. Tredger et L. M. Morgan. « The effects of dietary sugar-beet fibre and guar gum on lipid metabolism in Wistar rats ». British Journal of Nutrition 72, no 3 (septembre 1994) : 385–95. http://dx.doi.org/10.1079/bjn19940041.
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This study investigates the mechanisms of action for the hypocholesterolaemic effects of sugar-beet fibre (SBF) and gum gum. Four groups of ten male Wistar rats were fed ad lib. on test diets containing either 100 g SBF or guar/kg, or control diets containing 100 g cellulose or wheat bran/kg for 28 d. Food intake, weight gain and food consumption ratios were unaffected by the diets. Circulating cholesterol and hepatic cholesterol concentrations were significantly lower in both SBF- and guar-fed groups compared with either cellulose- or bran-fed animals. Circulating triacylglycerol concentrations were significantly lower in SBF- and guar-fed animals, but total hepatic lipid concentrations and hepatic and adipose tissue lipogenesis rates were unaffected by the diets. Hepatic cholesterol-7α-hydroxylase (EC1.14.13.17) activities were significantly higher in the guar-fed animals compared with cellulose or bran control groups. Hepatic 3-hydroxy-3-metbylglutaryl-CoA reductase (EC1.1.1.88) activities were unaffected. Circulating bile acid concentrations were significantly lower in SBF- and guar-fed animals and faecal bile acid output was significantly higher in the guar-fed group compared with bran- or cellulose-fed groups. This study supports the hypothesis that guar exerts its hypocholesterolaemic effect via intraluminal bile acid binding and loss of cholesterol from increased faecal bile acid excretion. The mechanism of action for the hypocholesterolaemic effect of SBF is less clear; the results of the present study point to a mechanism involving disruption of the enterohepatic bile acid circulation, possibly via changes in the rate of absorption of dietary lipid.
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Chance, Jenna A., Mike D. Tokach, Hilda I. Calderon, Jason C. Woodworth, Joel M. DeRouchey et Robert D. Goodband. « 245 Evaluation of Cellulose in Diets with and Without Added Zno on Nursery Pig Performance ». Journal of Animal Science 99, Supplement_1 (1 mai 2021) : 92–93. http://dx.doi.org/10.1093/jas/skab054.148.
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Abstract A total of 1,296 pigs (PIC L337×1050; initially 4.8 kg) were used in a 42-d study to evaluate cellulose in diets with and without pharmacological levels of Zn on nursery pig performance. Our hypothesis was that added fiber (cellulose) may provide more benefit in diets without ZnO. Pens were assigned to 1 of 4 dietary treatments in a RCBD by BW with 27 pigs/pen and 12 pens/treatment. Dietary treatments were arranged in a 2×2 factorial with main effects of cellulose (0 vs 1%; J. Rettenmaier USA, Schoolcraft, MI) and Zn (200 vs. 3,000 mg/kg in phase 1 and 110 vs. 2,000 mg/kg in phase 2). Treatment diets were formulated in two phases fed from d 0 to 7 and 7 to 21 with a common diet fed from d 21 to 42 post-weaning. Pig weights and feed disappearance were collected weekly to determine ADG, ADFI, and G:F. On d 16 or 17, fecal samples were collected from 3 pigs/pen to determine fecal DM, and all pens were visually evaluated for fecal consistency. There were no Zn×cellulose interactions. For the experimental and overall period, pigs fed diets containing added Zn had increased (P < 0.001) ADG, ADFI, G:F and BW while those that were fed cellulose had decreased (P < 0.05) ADG. For fecal dry matter, there was no evidence for difference (P >0.10) between any of the treatments but those fed added ZnO had visually firmer feces as evidenced by lower (P < 0.001) fecal scores. When fed a common diet from d 21 to 42, pigs previously fed added ZnO had increased (P < 0.001) ADG (502 vs. 523 g/d) and ADFI (697 vs. 734 g/d). In conclusion, there were no interactive effects between added cellulose and Zn; however, cellulose reduced ADG while the inclusion of pharmacological levels of Zn improved all growth criteria.
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Track, Norman S., Margaret E. Cawkwell, Beth C. Chin, Susan S. Chiu, Sean A. Haberer et Christopher R. Honey. « Guar gum consumption in adolescent and adult rats : short- and long-term metabolic effects ». Canadian Journal of Physiology and Pharmacology 63, no 9 (1 septembre 1985) : 1113–21. http://dx.doi.org/10.1139/y85-183.
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Metabolic responses to short- and long-term guar gum consumption were studied in adolescent and adult rats. For the Song-term study, male adolescent rats were divided into four groups (n = 60/group) and fed guar gum, cellulose, or bran diet for 67 weeks. Metabolic studies (food–water intake, feces–urine output, body weight, carbohydrate tolerance) were performed eight times during the 67 weeks. The guar gum group consumed less diet throughout the entire study and gained less weight over the first 20 weeks compared with the cellulose and bran groups. A second bran-fed group was food restricted over the first 20 weeks to match the reduced weight gain of the guar gum group and then fed ad libitum. Reduced plasma glucose excursions were measured for only the guar gum group after both fibre-free glucose and sucrose challenges at weeks 6, 12, and 18; from 24 to 64 weeks all four groups had similar glucose tolerance responses. Twenty-four hour urinary glucose excretion was similar during all eight metabolic studies up to 64 weeks for guar gum and cellulose groups. In the short-term study, male adolescent (200 g; n = 10/group) and adult (630 g; n = 15/group) rats were divided into five and four groups, respectively, and fed guar gum, guar by-product (GBP), cellulose, or bran diet for 6 weeks. A metabolic study was performed during the 6th week. Adolescent rats fed guar gum or GBP diets gained less weight than the cellulose group; only the guar gum group displayed improved carbohydrate tolerance. Adult rats had similar weight gain and carbohydrate tolerance responses to the four diets. Both adolescent and adult rats fed GBP had significantly reduced 24-h urinary glucose excretion. These studies suggest that adolescent rats respond to guar gum consumption with reduced body weight gain and improved carbohydrate tolerance and demonstrate that these responses are lost or absent in adult rats.
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Dong, Y., H. D. Bae, T. A. McAllister, G. W. Mathison et K. J. Cheng. « Effects of exogenous fibrolytic enzymes, α-bromoethanesulfonate and monensin on fermentation in a rumen simulation (RUSITEC) system ». Canadian Journal of Animal Science 79, no 4 (1 décembre 1999) : 491–98. http://dx.doi.org/10.4141/a99-024.
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The effects of exogenous fibrolytic enzymes, α-bromoethanesulfonate (BES) and monensin on fermentation and digestibility of grass hay were examined using two rumen simulation technique (RUSITEC) devices, each equipped with eight 820-mL fermenters with a liquid dilution rate of 0.73 d−1. Grass hay (10 g d−1) was fed either untreated or pre-treated with 0.2 g each of cellulase and xylanase, and in combination with no chemical or daily dosing of 20.5 µmol monensin, 20.5 µmol BES or 41 µmol BES. Pretreatment of hay with the fibrolytic enzymes increased (P < 0.05) organic matter (OM), cellulose and hemicellulose digestibilities by 9, 15, and 20%, respectively, and increased (P < 0.05) methane production per gram digestible OM by 43%. With the enzyme treatment, both β-endoglucanase and xylanase activities were enhanced (P < 0.05). Application of the enzymes promoted (P < 0.05) the growth of methanogenic bacteria, with no effect on total bacterial or cellulolytic bacterial populations. α-Bromoethanesulfonate did not influence digestibility, but depressed (P < 0.005) methane production by 51%. Addition of BES inhibited (P < 0.05) growth of methanogenic bacteria, with no effect on either the total or cellulolytic bacterial populations. Monensin depressed (P < 0.05) OM, cellulose and hemicellulose digestibilities by 15, 27 and 17%, respectively, and methane production by 78%. Treating grass hay with fibrolytic enzymes enhanced fiber digestion but also methane production. Including BES counteracted the methane production without affecting fiber digestion whereas monensin decreased both fiber digestion and methane production. Key words: Fibrolytic enzymes, α-bromoethanesulfonate, monensin, digestibility, methane, RUSITEC
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Sanou, Lassina. « Perceptions locales des perturbations écologiques sur la dynamique de la végétation de la réserve de biosphère transfrontalière Parc National du W, Afrique de l’Ouest ». Revue Ecosystèmes et Paysages 3, no 2 (30 décembre 2023) : 1–17. http://dx.doi.org/10.59384/recopays.tg3204.
Texte intégralRésumé :
L’activité humaine est au centre des perturbations écologiques et participe au processus lent de reconstitution des écosystèmes. Ce travail a été réalisé dans le Parc National du W et trois villages environnants avec pour objectif global de disposer de connaissances de base pouvant contribuer à une meilleure gestion des habitats des aires proté-gées. Des enquêtes menées auprès de 240 personnes visaient à recueillir leur perception des facteurs de perturbation écologiques (feu, pâture). Il ressort que les populations locales ont une bonne connaissance des effets de la pâture et des feux de brousses et perçoivent les activités humaines comme principale cause de la dégradation des forêts. Les facteurs de dégradation des formations végétales reconnus par les acteurs enquêtés sont par ordre décroissant : la croissance démographique (85,83%), les défrichements des terres pour l’extension des superficies culturales (84,58%), la variabilité climatique (80%), les feux de brousse (66,25%), la politique de gestion des formations végétales (61,67%). Les moyennes des scores de réponse des répondants sur leur per-ception de l’usage des feux et de la période de mise de feu précoce indiquent que les populations locales utilisent couramment les feux pour les défrichements des terres ( =2,69) et la période Novembre-Décembre est celle indiquée pour les feux précoces ( =3,03). La réussite des projets d’aménagement doit tenir compte des préoccupations des communautés locales et ne nécessite pas la suppression totale de la pâture et des feux tant que ces facteurs sont appliqués avec modération.
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Humeau, Mikael, Nathalie Papet, Louise Gotzamanis, Nenat Jaafari et Jean-Louis Senon. « Effets des réglementations en matière d'utilisation et de détention des armes à feu sur le taux de suicide ». Médecine & ; Droit 2006, no 79-80 (août 2006) : 134–41. http://dx.doi.org/10.1016/j.meddro.2006.07.004.
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Kim, Yeji, Sung Wook Hwang, Seungil Kim, Yong-Soo Lee, Tae-Young Kim, Su-Hyun Lee, Eun Na Kim et Mi-Na Kweon. « Dietary cellulose prevents gut inflammation by modulating lipid metabolism and gut microbiota ». Journal of Immunology 204, no 1_Supplement (1 mai 2020) : 83.28. http://dx.doi.org/10.4049/jimmunol.204.supp.83.28.
Texte intégralRésumé :
Abstract A Western diet comprising high fat, high carbohydrate, and low fiber content has been suggested to contribute to an increased prevalence of colitis. To clarify the effect of dietary cellulose (an insoluble fiber) on gut homeostasis, for 3 months mice were fed a high-cellulose diet (HCD) or a low-cellulose diet (LCD) based on the AIN-93G formulation. Histologic evaluation showed crypt atrophy and goblet cell depletion in the colons of LCD-fed mice. RNA-sequencing analysis showed a higher expression of genes associated with immune system processes, especially those of chemokines and their receptors, in the colon tissues of LCD-fed mice than in those of HCD-fed mice. The HCD was protective against dextran sodium sulfate-induced colitis in mice, while LCD exacerbated gut inflammation; however, the depletion of gut microbiota by antibiotic treatment diminished both beneficial and non-beneficial effects of the HCD and LCD on colitis, respectively. A comparative analysis of the cecal contents of mice fed the HCD or the LCD showed that the LCD did not influence the diversity of gut microbiota, but it resulted in a higher and lower abundance of Oscillibacter and Akkermansia organisms, respectively. Additionally, linoleic acid, nicotinate, and nicotinamide pathways were most affected by cellulose intake, while the levels of short-chain fatty acids were comparable in HCD- and LCD-fed mice. Finally, oral administration of Akkermansia muciniphila to LCD-fed mice elevated crypt length, increased goblet cells, and ameliorated colitis. These results suggest that dietary cellulose plays a beneficial role in maintaining gut homeostasis through the alteration of gut microbiota and metabolites.
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ROTTER, R. G., A. A. FROHLICH et R. R. MARQUARDT. « INFLUENCE OF DIETARY MANIPULATION ON THE DETRIMENTAL EFFECTS OF MOLD-CONTAMINATED BARLEY FED TO GROWING CHICKS ». Canadian Journal of Animal Science 69, no 4 (1 décembre 1989) : 1059–66. http://dx.doi.org/10.4141/cjas89-120.
Texte intégralRésumé :
The effects of feeding Penicillium cyclopium and Aspergillus flavus contaminated barley on Leghorn chicks were examined. Mycotoxin screening determined the mold-contaminated barley to be free of suspect toxins. This study examined the hypothesis that the effects of mold-contaminated barley are due to a deficiency of readily digestible nutrients, or some other factor. Chicks were fed diets containing either mold-free barley, a non-nutritive bulk (cellulose) plus mold-free barley, or a mold-contaminated barley (7% mold), in combination with low (2%) or high (10%) dietary tallow and supplemental starch (0 and 15%). High fat and starch supplementation both resulted in slightly higher weight gains for birds fed the mold-contaminated barley and cellulose containing diets, but the maximal improvement values were still more than 60 and 20%, respectively, lower than birds given a 6.7% tallow reference diet. Neither fat nor starch affected feed consumption. Birds fed the cellulose diet performed about 100% better than those given mold-contaminated barley, despite a theoretically lesser concentration of available nutrients in the former. Results of this study suggest the presence of some unidentified factor(s) in mold-contaminated. Key words: Mold-contaminated barley, mycotoxin, chick performance, starch, fat
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Bégin, Yves, Samuel Arseneault et Jean Lavoie. « Dynamique d’une bordure forestière par suite de la hausse récente du niveau marin, rive sud-ouest du golfe du Saint-Laurent, Nouveau-Brunswick ». Géographie physique et Quaternaire 43, no 3 (18 décembre 2007) : 355–66. http://dx.doi.org/10.7202/032788ar.
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RÉSUMÉ La transgression marine sur la côte sud du golfe du Saint-Laurent a notamment pour effet de provoquer la dégradation des marges forestières. Le déplacement de la ligne de rivage s'effectue à une vitesse moyenne de 1,11 m/an, correspondant ainsi à un taux de transgression marine de 10 à 50 cm/siècle. L'étude d'un site représentatif à la pointe Escuminac, au Nouveau-Brunswick, a permis de mettre en évidence les changements survenus au sein dune bande forestière au cours des dernières décennies. Par l'analyse dendrochronologique et l'étude de la structure des populations, nous avons retracé les étapes de la régression de l'épinette rouge sous l'effet combiné de la transgression de la nappe d'eau marine et de la migration d'une plage qui lui est associée et d'autres perturbations non reliées à la dynamique littorale (feu et épidémies de tordeuse des bourgeons). La forêt étudiée tient son origine d'un feu datant du début du siècle. Elle a depuis été atteinte par deux épidémies de tordeuse l'une en 1914-17 et l'autre en 1954-58, tout en subissant progressivement les effets d'une humidité croissante. Les résultats indiquent que dans le processus de dépérissement des forêts. Ia transgression marine a joué un double rôle: celui de modifier les conditions de drainage des sols supra-riverains menant à la réduction de la croissance secondaire des arbres, et celui de limiter la régénération forestière après perturbation. L'analyse dendrochronologique permet ainsi de retracer sur une base spatiotemporelle l'ensemble des transformations ayant caractérisé la zone littorale au cours du dernier siècle.
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Fontanille, Jacques. « Lumières, matières et paysages ». Protée 31, no 3 (27 mai 2004) : 17–30. http://dx.doi.org/10.7202/008434ar.
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Résumé Parmi tous les effets de lumière, on a choisi de prêter attention à l’un d’eux, car il a trait aux rapports entre le temps et la matière : il s’agit de la « lumière intérieure » dans le paysage. La lumière interne devient alors une propriété des objets et de leur structure matérielle, en plusieurs directions : l’animation actantielle, puisque l’intensité de l’éclat émane de l’objet ; la modalité et l’aspectualité, puisque la matière module la « restitution » de cet éclat ; la temporalité, enfin, puisque la perception de ces lumières est alors dissociée de celle de la source et du moment de l’émission. Ces remarques générales sont exploitées au cours d’une analyse des Fleurs du Mal, de Baudelaire, où on examine notamment le « feu du regard », la « lumière voilée » et le « soleil lavé ». Elles sont ensuite étendues à une réflexion sur le « paysage », conçu comme configuration sémiotique émanant du monde naturel, à la rencontre entre une « existence » et une « expérience ».
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Hammers, Kelsey, Hilda I. Calderon, Mike D. Tokach, Jason C. Woodworth, Robert D. Goodband, Steve S. Dritz et Joel M. DeRouchey. « 244 Effect of Fiber Source and Crude Protein Level on Nursery Pig Performance ». Journal of Animal Science 99, Supplement_1 (1 mai 2021) : 94–95. http://dx.doi.org/10.1093/jas/skab054.152.
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Abstract A total of 360 pigs (DNA 200′400, initially 5.0 kg) were used in a 45-d growth trial to determine the effects of fiber source and crude protein (CP) level in diets without pharmacological levels of ZnO on nursery pig growth performance and fecal dry matter (DM). Pigs were randomly assigned to 1 of 8 treatments with 5 pigs/pen and 9 pens/treatment. Treatments were arranged in a 2×4 factorial with main effects of CP (21 or 18%) and fiber source [none, coarse wheat bran (CWB), oat hulls, or cellulose (Arbocel, J. Rettenmaier USA, Schoolcraft, MI)]. Fiber source was added to equalize the level of insoluble fiber contributed from 4% CWB, resulting in the addition of 1.85% oat hulls or 1.55% cellulose. Diets were fed in two phases (d 0 to 10 and 10 to 24) followed by a common diet (d 24 to 45). The 21% CP diets contained 1.40% SID Lys in phase 1 and 1.35% SID Lys in phase 2. Treatment diets were formulated to a maximum SID Lys:digestible CP level of 6.35%, thus SID Lys decreased in the 18% CP (1.25% SID Lys) diets. Data were analyzed using the lmer function in R. No fiber source × CP level interactions (P >0.05) were observed. Decreasing dietary CP decreased (P = 0.05) ADG, G:F, and d 24 BW. Overall, ADG and d 45 BW decreased (P < 0.05) for pigs fed 18% CP diets. No main effects of fiber source were observed for growth performance throughout the study. Fecal DM increased (P < 0.05) for pigs fed added cellulose compared to pigs fed no fiber or CWB in the experimental period. In conclusion, reducing dietary CP decreased growth performance and the inclusion of cellulose improved fecal DM of nursery pigs.
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Li, Shijun, Liuqing Yang et Shengtao Li. « Effects of Long-Term Vibration on Cellulose Degradation in an Oil-Impregnated Pressboard under Simultaneous Thermal–Electrical–Mechanical Stress Aging ». Energies 15, no 7 (31 mars 2022) : 2547. http://dx.doi.org/10.3390/en15072547.
Texte intégralRésumé :
Due to the complex operation conditions in a power transformer, an oil-impregnated pressboard (OIP) simultaneously suffers from thermal, electrical, and mechanical stress. Since most research studies have paid much attention to thermal or electrical aging of OIPs, this paper analyzes the effects of long-term mechanical vibrations on cellulose degradation in OIPs under simultaneous multi-stress. The aging experiments were firstly conducted at 130 °C, with a DC electric voltage of +6 kV, vibration amplitude of 10–50 μm, and vibration frequency of 100–300 Hz. The finite element analysis (FEA) of the pressboard vibration model was then performed on Abaqus to investigate the time–frequency domain characteristic parameters of compressive stress on the pressboard under varied vibration frequencies and amplitudes. The FEA results reveal that compressive stress on the pressboard in a multi-stress aging experiment coincided with the axial compressive stress on the insulation spacers in an SZ-50000/110 transformer. Moreover, combined with the degree of polymerization (DP) of cellulose, the effects of long-term vibration on cellulose degradation are reflected in two ways: the increase in compressive stress on the pressboard generates more links available for degradation, while more high frequency harmonic components in compressive stress accelerate the reaction rate in cellulose degradation.
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Finet, Shannon E., Fei He, Lindsay V. Clark et Maria R. de Godoy. « 112 Modulating Effects of Miscanthus Grass and Prebiotic Blends on Canine Fecal Microbiota, Metabolites, and Digestibility ». Journal of Animal Science 99, Supplement_3 (8 octobre 2021) : 56–57. http://dx.doi.org/10.1093/jas/skab235.101.
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Abstract Dietary fiber plays an important role in gastrointestinal health as it modulates the gut environment and promotes microbiome homeostasis. However, dietary fiber sources vary in composition, physico-chemical properties, and physiological effects. The objective of this study was to evaluate the effects of miscanthus grass fiber and prebiotic fiber blends on fecal microbiota, fecal metabolites, and apparent total tract digestibility in comparison to traditional dietary fiber sources. Animal procedures were approved by the University of Illinois Institutional Animal Care and Use Committee. Six dietary treatments were formulated to meet or exceed AAFCO nutrient profile (2018) and included either cellulose, beet pulp, miscanthus fiber, or a blend of miscanthus fiber and tomato pomace, miscanthus fiber and resistant starch, or miscanthus fiber and fructooligosaccharide. Twelve female adult beagles were randomly assigned one of the six treatments in a replicated 6x6 Latin square design and fed for 21 d including 17 d of diet adaptation followed by 4 d of total and fresh fecal collection. All diets were well digested by the animals. Dogs fed beet pulp had greater fecal total short-chain fatty acid concentration than the cellulose treatment (P < 0.05), while the dogs fed diets containing miscanthus fiber were intermediate. No difference in the α-diversity of fecal microbial communities was observed among treatments (P >0.05), while β-diversity of dogs fed the beet pulp treatment differed from the other treatment groups. Miscanthus grass can be utilized successfully in diets for adult dogs with tomato pomace and resistant starch blends resulting in similar physiological effects to cellulose.
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Horbelt, Nils, John W. C. Dunlop, Luca Bertinetti, Peter Fratzl et Michaela Eder. « Effects of moisture and cellulose fibril angle on the tensile properties of native single Norway spruce wood fibres ». Wood Science and Technology 55, no 5 (5 juillet 2021) : 1305–18. http://dx.doi.org/10.1007/s00226-021-01315-4.
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AbstractIsolated single wood fibres with cellulose fibril angles from 10 to 43° were tested in microtensile tests under controlled temperature and relative humidity of 5, 50, 75, 90% and in the wet state. This systematic study provides experimental stiffness and strength data, calculated on cell wall cross sections. It has been shown that stiffness reduction with increasing moisture content is more pronounced in fibres with large cellulose fibril angles. Interestingly, stiffness reduction in fibres with low cellulose fibril angles has been observed for the fully hydrated state only. The experimental dataset was fed into a model to determine moisture dependent stiffness of the hemicellulose-lignin-matrix and the stresses acting on the fibrils and the matrix.
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El-Wahab, Amr Abd, Jan Berend Lingens, Julia Hankel, Christian Visscher et Cristina Ullrich. « Effect of Different Fiber Sources as Additives to Wet Food for Beagle Dogs on Diet Acceptance, Digestibility, and Fecal Quality ». Veterinary Sciences 10, no 2 (25 janvier 2023) : 91. http://dx.doi.org/10.3390/vetsci10020091.
Texte intégralRésumé :
In order to enhance the health and welfare of obese dogs and to facilitate the required loss of body weight, commercial diets are produced with fibrous ingredients. Cellulose is a common dietary fiber used mainly in powdered form. However, other processing forms and fibers are available as fibrous additives. This work aimed to test the effects of different fiber sources on apparent total tract digestibility and fecal quality in dogs. Four diets were fed to eight dogs (experimental design: 4 × 4 Latin square) for a 14-day period each. In addition to a basal diet (CO), three experimental diets varying in fiber sources were used: powdered cellulose (CE), granulated cellulose (GC), and lignocellulose (LC). Dogs fed the CO had lower crude fiber digestibility than those fed the other experimental diets (p < 0.0033). Dogs fed diets supplemented with fiber sources had lower gross energy digestibility (range: 76.2–77.3%) compared with those fed the CO (84.4%). In all groups, the fecal score (consistency and shape) ranged within the optimal values; solely wet fecal output was increased for the fiber groups compared with those on the CO. This study demonstrated that various sources of fiber such as GC and LC can be used as alternatives to CE without restrictions.
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Singh, Vishal, Beng San Yeoh et Matam Vijay-Kumar. « Fermentable Fiber Pectin Improves Intestinal Inflammation by Modulating Gut Microbial Metabolites and Inflammasome Activity ». Current Developments in Nutrition 4, Supplement_2 (29 mai 2020) : 1535. http://dx.doi.org/10.1093/cdn/nzaa068_020.
Texte intégralRésumé :
Abstract Objectives Appreciation of the therapeutic benefits of fermentable dietary fibers (FDFs) in inflammatory bowel disease (IBD) is continuously growing. Herein, we examined the effect, and underlying mechanism(s), of FDF pectin on IBD development by using a preclinical model of intestinal inflammation. Methods Chronic colitis was induced in dietary cellulose or pectin-fed WT mice by administering four weekly injections of interleukin (IL)-10 receptor neutralizing antibody. Mice were euthanized two weeks after the last injection, and colitis development was examined by gross colon appearance, serological, and histological markers. Results The control group, which received insoluble fiber cellulose, developed extensive colonic inflammation as evident via colomegaly, splenomegaly, elevated pro-inflammatory cytokines including IL-1β, and distorted colonic crypts. Relative to cellulose, the level of inflammatory cytokines and histological scores were reduced in the pectin-fed mice. To understand the mechanism(s) by which dietary pectin alleviated intestinal inflammation, we analyzed the gut microbiota composition, its metabolic products, and inflammation regulators in our model. Compared to cellulose, pectin reduced the abundance of Verrucomicrobia and elevated acetate, an immune response modulator, in the cecal content. Inline, pectin-fed mice displayed reduced colonic IL-1β and heightened expression of inflammasome component NLRC4 in colonic epithelial crypts. Moreover, the colonic level of IL-1 receptor antagonist (IL-1Ra, a natural endogenous inhibitor of IL-1β), whose expression is partly regulated via NLRC4, was also elevated in mice fed pectin. The lack of pectin-mediated protective effects in NLRC4-deficient and IL-1Ra-deficient mice indicated that the NLRC4-IL-1Ra axis executes the beneficial effects of pectin during gut inflammation. Considering that IL-1Ra restrains the pro-inflammatory activity of IL-1β, this study suggests that pectin derived metabolites promote NLRC4 signaling, which augments IL-1Ra and thus limits IL-1β mediated colonic inflammation. Conclusions Altogether, our study demonstrates that microbial metabolism, of FDFs, and NLRC4 inflammasome axis mediates the beneficial effects of pectin in the inflamed gut. Funding Sources Career Development Award [ID# 597,229] from Crohn's & Colitis Foundation (CCF).
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Shafey, TM. « Effects of chelating agents on the performance of growing chickens fed high calcium diets ». Australian Journal of Experimental Agriculture 31, no 6 (1991) : 765. http://dx.doi.org/10.1071/ea9910765.
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The effects of supplementation with chelating agents on the growth performance of chickens fed high calcium diets were investigated in 2 experiments. In experiment 1, increasing dietary calcium to 25.2 g/kg significantly reduced body weight gain and feed efficiency. The addition of phytic acid (10 g/kg) tended to improve body weight gain of chickens fed high calcium diets; however, the gain was not significantly different from that of birds fed the high calcium diet. The addition of either Na2EDTA (1 g/kg) or proline (10 g/kg) to a high calcium diet did not affect body weight gain or feed efficiency of chickens. In experiment 2, increasing dietary calcium to 26 g/kg significantly reduced body weight gain and feed efficiency and increased plasma total calcium concentration. The addition of cellulose significantly (P<0.01) reduced plasma calcium and tibia calcium concentrations; however, the performance of chickens fed high calcium diets was not affected by the addition of cellulose. It was concluded that chelating agents differ in their ability to eliminate the toxic effects of high calcium diets, and that the addition of phytic acid at 1% was most successful in eliminating the growth depressing effect of high dietary calcium.
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Mälkki, Y., R. Törrönen, K. Pelkonen, O. Myllymäki, O. Hänninen et K. Syrjänen. « Effects of oat-bran concentrate on rat serum lipids and liver fat infiltration ». British Journal of Nutrition 70, no 3 (novembre 1993) : 767–76. http://dx.doi.org/10.1079/bjn19930172.
Texte intégralRésumé :
Oat bran concentrated with respect to both soluble and insoluble dietary fibre was fed to adult rats, and its effects on serum cholesterol and liver fat infiltration were studied. The feeds contained 15, 30 or 45 g β-glucan/kg, except in control groups where the fibre of the feed was cellulose. Half the experimental groups received the feeds with an addition of 10 g cholesterol and 2 g cholic acid/kg in order to create an hypercholesterolaemic condition. In normocholesterolaemic rats the concentrated oat bran did not cause any significant changes in serum cholesterol concentrations, but reduced liver weight compared with control group rats fed on the cellulose-containing diet. In hypercholesterolaemic rats the concentrated oat bran reduced serum total cholesterol and increased high-density-lipoprotein cholesterol concentration. The effect was seen already at the 15 g/kg concentration of β-glucan, the higher doses tested did not significantly improve the effect. Infiltration of fat into liver cells, especially in the periportal areas, was observed only in hypercholesterolaemic animals. The fat infiltration was accentuated in proportion to the amount of oat-bran concentrate fed.
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Hayashi, Kumiko, Hiroshi Hara, Patchana Asvarujanon, Yoritaka Aoyama et Pairojana Luangpituksa. « Ingestion of insoluble dietary fibre increased zinc and iron absorption and restored growth rate and zinc absorption suppressed by dietary phytate in rats ». British Journal of Nutrition 86, no 4 (octobre 2001) : 443–51. http://dx.doi.org/10.1079/bjn2001417.
Texte intégralRésumé :
We examined the effects of ingestion of five types of insoluble fibre on growth and Zn absorption in rats fed a marginally Zn-deficient diet (6·75 mg (0·103 mmol) Zn/kg diet) with or without added sodium phytate (12·6 mmol/kg diet). The types of insoluble fibre tested were corn husks, watermelon skin, yam-bean root (Pachyrhizus erosus) and pineapple core, and cellulose was used as a control (100 g/kg diet). Body-weight gain in the cellulose groups was suppressed by 57 % by feeding phytate. Body-weight gain in phytate-fed rats was 80 % greater in the watermelon skin fibre and yam-bean root fibre group than that in the cellulose group. Zn absorption ratio in the cellulose groups was lowered by 46 and 70 % in the first (days 7–10) and second (days 16–19) measurement periods with feeding phytate. In the rats fed the phytate-containing diets, Zn absorption ratio in the watermelon skin, yam-bean root and pineapple core fibre groups was 140, 80 and 54 % higher respectively than that in the cellulose group, in the second period. Fe absorption was not suppressed by phytate, however, feeding of these three types of fibre promoted Fe absorption in rats fed phytate-free diets. The concentration of soluble Zn in the caecal contents in the watermelon skin fibre or yam-bean root fibre groups was identical to that in the control group in spite of a higher short-chain fatty acid concentration and lower pH in the caecum. These findings indicate that ingestion of these types of insoluble fibre recovered the growth and Zn absorption suppressed by feeding a high level of phytate, and factors other than caecal fermentation may also be involved in this effect of insoluble fibre.
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Wattanakul, Wattana, Karun Thongprajukaew, Waraporn Hahor et Naraid Suanyuk. « Optimal Replacement of Soybean Meal with Fermented Palm Kernel Meal as Protein Source in a Fish Meal-Soybean Meal-Based Diet of Sex Reversed Red Tilapia (Oreochromis niloticus × O. mossambicus) ». Animals 11, no 8 (3 août 2021) : 2287. http://dx.doi.org/10.3390/ani11082287.
Texte intégralRésumé :
The solid-state fermentation by effective microorganisms (containing photosynthetic bacteria, lactic acid bacteria, nitrogen-fixing bacteria, yeast and Bacillus sp.) improved the nutritive values of palm kernel meal (PKM). Increased crude protein (20.79%), nitrogen-free extract (40.07%) and gross energy (19.58%) were observed in fermented PKM (FPKM) relative to raw PKM while crude lipid (15.65%), crude fiber (36.45%) and ash (29.54%) were decreased. Replacement of soybean meal (SBM) with FPKM as a protein source was investigated for its effects in sex-reversed red tilapia (Oreochromis niloticus × O. mossambicus). The two-month-old fish (14.85 ± 0.28 g initial weight) were fed fish meal-SBM-based diets with replacement by FPKM at 25% (25FPKM), 50% (50FPKM), 75% (75FPKM) and 100% (100FPKM), while an FPKM-free diet (0FPKM) was used as a control. The five treatments, comprising triplicate cement ponds and forty fish each, were conducted in a recirculating system over 12 weeks. At the end of the feeding trial, fish fed the 50FPKM diet were superior in growth performance, while the feed utilization parameters were similar across all five treatments. Physiological adaptation of the protein-digesting (pepsin and trypsin) and lipid-digesting (lipase) enzymes was detected at all protein replacement levels (except for 25FPKM), as well as of the enzyme for cellulose digestion (cellulase), but not of the carbohydrate-digesting enzymes (amylase). Protein synthesis capacity in flesh was improved in fish fed the 50FPKM diet, while the quality of the main flesh proteins, actin and myosin, showed no significant differences across the five treatments. No differences in carcass composition and no negative effects on hematological parameters or liver histoarchitecture at the 50% replacement level of SBM by FPKM also support this alternative. Findings from the current study indicate the low-cost FPKM-containing diet for tilapia in comparison with control diet.
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Mangi, Mazhar Hussain, Tariq Hussain, Muhammad Suhaib Shahid, Naveed Sabir, Muhammad Saleem Kalhoro, Xiangmei Zhou et Jianmin Yuan. « Effects of Flaxseed and Multi-Carbohydrase Enzymes on the Cecal Microbiota and Liver Inflammation of Laying Hens ». Animals 11, no 3 (25 février 2021) : 600. http://dx.doi.org/10.3390/ani11030600.
Texte intégralRésumé :
Background: The use of wheat and flaxseed to produce omega-3 (ω-3) enriched poultry meat and eggs is very popular in the world. However, wheat and flaxseed contain some anti-nutritional factors (ANFs), and enzymes are usually used to alleviate the deleterious influence of ANFs. Method: A 2 × 3 two factors design was used in the experiment. A total of 540 twenty-week-old Nongda-3 laying hens were randomly allocated to six dietary treatments, two diets (corn/flaxseed and wheat/flaxseed), and three enzymes (enzyme-a contains neutral protease 10,000, xylanase 35,000, β-mannanase 1500, β-glucanase 2000, cellulose 500, amylase 100, and pectinase 10,000 (U g−1); enzyme-b contains alkaline protease 40,000 and neutral protease 10,000 (U g−1); enzyme-c contains alkaline protease 40,000, neutral protease 10,000, and cellulase 4000 (U g−1). Results: There was an interaction between dietary treatment and supplemental enzymes for liver weight and liver inflammatory cytokines of broilers. A significant increase was observed in the fat weight of birds fed a corn diet as compared with a wheat diet. A corn diet and wheat diet with the addition of enzyme-a (p < 0.001) showed the highest level of liver fat followed by enzyme-c (p < 0.01) and enzyme-b. Moreover, a high level of secretory IL-1β, IL-6, and IL-10 and comparatively higher inflammatory changes in the liver tissue were found in birds fed a corn diet as compared with a wheat diet, and enzyme-b showed more beneficial effects as compared with enzyme-a and -c. The gut microbial composition of hens fed a corn diet was significantly different than that of birds fed a wheat diet. Bacteroides were significantly (p < 0.05) abundant in the corn-fed birds as compared with wheat-fed birds. However, Firmicutes were less abundant in the wheat-fed birds than the corn-fed birds (16.99 vs. 31.80%, respectively). The microbial community at the genus level differed significantly in the dietary groups and we observed that Bacteroides are the predominant cecal microbiota. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of co-factors, carbohydrates, vitamins, protein, and energy were expressed at slightly higher levels in the microbiota of the wheat-fed birds, whereas, metabolic pathways for nucleotides, lipids, and glycine were expressed at higher levels in the wheat-fed birds. Furthermore, expression of the growth and cellular processes pathway and endocrine system pathway levels were predicted to be higher for the wheat-fed group as compared with the corn-fed group. Conclusions: In conclusion, our findings suggest that inflammatory changes in laying birds were mediated by a corn diet with flaxseed and enzymes instead of a wheat diet. Additionally, in the wheat-fed group, enzyme-b and -c showed more encouraging results as compared to enzyme-a.
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SUN, Y., K. G. KOSKI, L. J. WYKES et M. E. SCOTT. « Dietary pectin, but not cellulose, influences Heligmosomoides polygyrus (Nematoda) reproduction and intestinal morphology in the mouse ». Parasitology 124, no 4 (avril 2002) : 447–55. http://dx.doi.org/10.1017/s0031182001001391.
Texte intégralRésumé :
Dietary texture has been reported to influence parasite establishment and survival, but to what degree this relationship is modified by either the type or quantity of dietary fibre is unknown. Using a 2×4 factorial design, we explored the relationship between fibre type (soluble = pectin vs insoluble = cellulose) and fibre quantity (0, 5, 10 and 20% by dry weight) on parasitic outcomes in BALB/c mice infected with 100 Heligmosomoides polygyrus (Nematoda) larvae. Pectin, but not cellulose, exerted a significant effect on parasite egg production. Following in vitro culture of female worms, increasing levels of dietary pectin were associated with increasing release of eggs. Yet this pattern was not observed in vivo, where per capita egg production peaked at the 10% pectin concentration, but was very low in mice fed 20% pectin. Parasite establishment was elevated in mice fed 20% pectin, but was unaffected by cellulose concentration. Neither type nor quantity of fibre affected H. polygyrus survival or spatial distribution along the gastrointestinal tract. To what degree differences in parasite establishment and reproduction could be attributed to the marked effects of pectin on gut morphology (increased intestinal length, villus length, mucosa thickness and villus/crypt ratio) requires further exploration. Our data indicate that cellulose is preferable to pectin as the source of fibre for experimental diets as cellulose did not affect H. polygyrus establishment, reproduction or survival during a 4-week primary infection.
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Igarashi, Miki, Miku Morimoto, Asuka Suto, Akiho Nakatani, Tetsuhiko Hayakawa, Kenjirou Hara et Ikuo Kimura. « Synthetic dietary inulin, Fuji FF, delays development of diet-induced obesity by improving gut microbiota profiles and increasing short-chain fatty acid production ». PeerJ 8 (8 avril 2020) : e8893. http://dx.doi.org/10.7717/peerj.8893.
Texte intégralRésumé :
Background Dietary fiber, including inulin, promotes health via fermentation products, such as short-chain fatty acids (SCFAs), produced from the fiber by gut microbiota. SCFAs exert positive physiological effects on energy metabolism, gut immunity, and the nervous system. Most of the commercial inulin is extracted from plant sources such as chicory roots, but it can also be enzymatically synthesized from sucrose using inulin producing enzymes. Studies conducted on rodents fed with a cafeteria diet have suggested that while increasing plasma propionic acid, synthetic inulin modulates glucose and lipid metabolism in the same manner as natural inulin. Therefore, this study aimed to determine the effects of a synthetic inulin, Fuji FF, on energy metabolism, fecal SCFA production, and microbiota profiles in mice fed with a high-fat/high-sucrose diet. Methods Three-week-old male C57BL/6J mice were fed a high-fat/high-sucrose diet containing cellulose or Fuji FF for 12 weeks, and the effects on energy metabolism, SCFA production, and microbiota profiles were evaluated. Results Body weight gain was inhibited by Fuji FF supplementation in high-fat/high-sucrose diet-fed C57BL/6J mice by reducing white adipose tissue weight while increasing energy expenditure, compared with the mice supplemented with cellulose. Fuji FF also elevated levels of acetic, propionic and butyric acids in mouse feces and increased plasma propionic acid levels in mice. Moreover, 16S rRNA gene amplicon sequencing of fecal samples revealed an elevated abundance of Bacteroidetes and a reduced abundance of Firmicutes at the phylum level in mice supplemented with Fuji FF compared to those supplemented with cellulose. Fuji FF also resulted in abundance of the family Bacteroidales S24-7 and reduction of Desulfovibrionaceae in the feces. Conclusion Long term consumption of Fuji FF improved the gut environment in mice by altering the composition of the microbiota and increasing SCFA production, which might be associated with its anti-obesity effects.
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Otuechere, Chiagoziem A., Adewale Adewuyi, Olusegun L. Adebayo, Emmanuel Yawson, Omolara Kabiawu, Sarah Al-Rashed, Blessing Okubio, Amany M. Beshbishy et Gaber El-Saber Batiha. « Histomorphological and Redox Delineations in the Testis and Epididymis of Albino Rats Fed with Green-Synthesized Cellulose ». Biology 9, no 9 (25 août 2020) : 246. http://dx.doi.org/10.3390/biology9090246.
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It has also become increasingly necessary to diversify the production of cellulose for biomedical applications. In this study, cellulose-green-synthesized from Sesamum indicum (GSC)—was administered orally to rats for 14 days as follows: control, 100, 200 and 400 mg/kg GSC. The impact of GSC on the antioxidant status and histomorphology of the testes and epididymis were studied. GSC had no effects on organ weights and organosomatic indices. In the testes, GSC caused nonsignificant changes in superoxide dismutase, catalase, reduced glutathione and nitric oxide levels, whereas it significantly decreased glutathione peroxidase and malondialdehyde levels. In the epididymis, GSC significantly decreased superoxide dismutase and nitric oxide levels, but caused a significant increase in glutathione peroxidase and reduced glutathione levels. Furthermore, at ×200 magnification, testicular morphology appeared normal at all doses, however, extravasation of the germinal epithelium of the epididymis was observed at doses of 200 and 400 mg/kg GSC. Conversely, at ×400 magnification, spermatogenic arrest (testes) and chromatolytic alterations (epididymis) were observed at the higher doses (200 and 400 mg/kg GSC). This study reports on the effect of green-synthesized cellulose on testicular and epididymal histology and redox status and further extends the frontiers of research on cellulose.
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Gee, J. M., W. Lee-Finglas et I. T. Johnson. « Fermentable carbohydrate modulates postprandial enteroglucagon and gastrin release in rats ». British Journal of Nutrition 75, no 5 (mai 1996) : 757–66. http://dx.doi.org/10.1079/bjn19960179.
Texte intégralRésumé :
We studied the effects of a fermentable sugar-alcohol (lactitol) on the concentrations of enteroglucagon and gastrin in the blood of rats for 7·5 h after feeding. The control and treatment groups were fed on semi-purified diets containing either non-fermentable cellulose or lactitol respectively, at 100 g/kg. Compared with the cellulose-fed group, the animals fed with lactitol had higher levels of enteroglucagon (5−10 times higher than control; P < 0·05) and lower serum gastrin (70−80% of control; P< 0.·05) for several hours after the withdrawal of feed. In contrast, varying the level of dietary lipid (maize oil) over a range of 8−120 g/kg had no effect on the release of either peptide. These results suggest that poorly absorbed fermentable dietary carbohydrate stimulates postprandial plasma enteroglucagon and inhibits serum gastrin release in the rat. The mechanism is uncertain but an endocrine response by the colon to fermentation products seems probable.
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Zhai, Xichuan, Dehui Lin, Yan Zhao, Wenwen Li et Xingbin Yang. « Enhanced anti-obesity effects of bacterial cellulose combined with konjac glucomannan in high-fat diet-fed C57BL/6J mice ». Food & ; Function 9, no 10 (2018) : 5260–72. http://dx.doi.org/10.1039/c8fo01211c.
Texte intégralRésumé :
This study aimed to investigate the effects of supplementation with bacterial cellulose (BC), konjac glucomannan (KGM) and combined BC/KGM fiber on high-fat (HF)-diet-induced obesity in C57BL/6J mice.
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Grbić, Jovana, Aleksandra Đukić-Vuković, Dragana Mladenović, Saša Lazović et Ljiljana Mojović. « Effect of non-thermal plasma on cellulose crystallinity and lignin content in corn stalks ». Journal on Processing and Energy in Agriculture 26, no 2 (2022) : 52–56. http://dx.doi.org/10.5937/jpea26-36871.
Texte intégralRésumé :
Lignocellulosic biomass is a cheap raw material that, thanks to its high carbohydrate content, can be used in fermentation to produce biofuels, biogas and other compounds. Its complex structure, including cellulose, hemicellulose and lignin, requires prior treatment of the biomass to facilitate hydrolysis to simple sugars. Today, biomass is only partially utilized and generates about 14% of the world's energy. This is because the most commonly used physical, chemical and physicochemical treatments are not sustainable. They are energy-consuming but still low in productivity and toxic inhibitors formed during these treatments could hinder later steps of fermentation. Biomass treatment with advanced oxidation techniques has great potential as an environmentally friendly, so-called "green" treatment. These processes generate reactive species (radicals, electrons, ions and peroxides) that attack cellulose, hemicellulose, and lignin components. In this work, the effects of non-thermal plasma, the Fenton process, and the combined treatment of corn stalks with non-thermal plasma/Fenton were compared. Grounded biomass of corn stalks was mixed with Fenton reagent and hydrogen peroxide at different ratios and subjected to non-thermal plasma treatment. Carbohydrate content was decreased in non-thermal plasma treated samples both with and without Fe2+. However, a specific biomass: Fe2+:H2O2 ratio was required to achieve the highest rate of lignocellulose decomposition. The cellulose and hemicellulose fractions were affected and reduced by the treatments studied but resulted in almost no changes in the cellulose crystallinity index. The lower lignin content and cellulose crystallinity allow for more efficient enzyme hydrolysis of the treated lignocellulose and new options for valorization in fermentations.
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Yang, Yongshou, Thanutchaporn Kumrungsee, Norihisa Kato, Shinji Fukuda, Manabu Kuroda et Shotaro Yamaguchi. « Aspergillus-Derived Cellulase Preparation Exhibits Prebiotic-like Effects on Gut Microbiota in Rats ». Fermentation 8, no 2 (8 février 2022) : 71. http://dx.doi.org/10.3390/fermentation8020071.
Texte intégralRésumé :
Aspergillus-derived cellulase, which is involved in the production of Aspergillus-fermented foods, has been employed in the food and animal feed industries. However, the effect of dietary Aspergillus cellulase on health is poorly understood. Previously, we discovered that supplemental Aspergillus-derived protease and lipase preparations had substantial bifidogenic effects on rats fed a high-fat diet. Therefore, this study reports on the effects of a 0.1% dietary Aspergillus-derived cellulase preparation (CEL) on the gut microbiota of rats fed a high-fat diet. Gene sequencing analysis of 16S rRNA revealed that CEL treatment markedly affected the microbiota profiles of the cecal contents (p < 0.05). Notably, CEL markedly increased the relative abundance (RA) of typical probiotics, such as Bifidobacterium and Lactobacillus, at the genus level (28- and 5-fold, respectively, p < 0.05). Similarly, at the family level, CEL treatment significantly increased the RA of Bifidobacteriaceae and Lactobacillaceae (p < 0.05). Furthermore, CEL increased the RA of other genera, such as Collinsella and Enterococcus, but decreased the RA of Oscillospira, Dorea and Coprobacillus (p < 0.05). The effects on these genera are similar to those reported for typical prebiotic oligosaccharides. Overall, this study demonstrates the prebiotic-like effects of dietary CEL by significantly increasing Bifidobacterium and Lactobacillus abundance.
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Khatun, Shahanaz, Md Ashraduzzaman, Md Rezaul Karim, Farzana Pervin, Nurul Absar et Ahmad Rosma. « Purification and characterization of peroxidase from Moringa oleifera L. leaves ». BioResources 7, no 3 (7 juin 2012) : 3237–51. http://dx.doi.org/10.15376/biores.7.3.3237-3251.
Texte intégralRésumé :
Peroxidase catalyzes the oxidation of various electron donor substrates such as phenol and aromatic amines in the presence of hydrogen peroxide. In this study, peroxidase was purified 164-fold from the leaves of Moringa oleifera L. with a recovery of 28% by ammonium sulphate precipitation, DEAE-cellulose column chromatography, Sephadex G-200 column chromatography, and Con-A column chromatography. SDS-PAGE showed a polypeptide band with molecular weight of 43 kDa. The enzyme was found to be a single subunit in nature. The purified enzyme displayed optimum activity at pH 6.0 and at a temperature of 50 °C with a Km value of 0.2335 mM for guaiacol as best substrate. It is a glycoprotein that contains 9.05% sugar as estimated by the phenol sulfuric acid method. Some ions (Ni2+, Pb2+, Zn2+, Al3+, Mg2+, Cu2+, Co2+, and Cd2+) exhibited low inhibitory effect while Fe2+, Fe3+, and Hg2+ exhibited strong inhibitory effects. EDTA markedly inhibited the peroxidase activity.
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Cholewińska, Ewelina, Aleksandra Marzec, Przemysław Sołek, Bartosz Fotschki, Piotr Listos, Katarzyna Ognik et Jerzy Juśkiewicz. « The Effect of Copper Nanoparticles and a Different Source of Dietary Fibre in the Diet on the Integrity of the Small Intestine in the Rat ». Nutrients 15, no 7 (24 mars 2023) : 1588. http://dx.doi.org/10.3390/nu15071588.
Texte intégralRésumé :
The aim of the study was to verify the hypothesis regarding the effect of recommended (6.5 mg/kg) or enhanced (13 mg/kg) level of CuNPs in the diet in combination with different types of dietary fibre—cellulose (control), inulin, pectin or psyllium—on selected biological parameters of intestinal integrity in rats. Rats were randomly divided into 10 groups. The first two groups were fed a control diet that contained cellulose, and a mineral mixture with standard or enhanced content of CuCO3. Experimental groups were fed a diet supplemented with CuNPs (6.5 or 13 mg/kg) and combined with different types of fibre (cellulose, pectin, inulin or psyllium). After the feeding period, blood and small intestine samples were collected for further analysis. Replacing CuCO3 by CuNPs in the diet positively reduced the level of lactic acid and apoptosis markers in the small intestine; however, it also resulted in the intensification of DNA oxidation. The most beneficial effect on DNA repair mechanisms is related to inulin, while pectin has the greatest ability to inhibit inflammatory processes that induce the apoptotic death of cells in the small intestine. Our results suggest that dietary fibre supplementation protects the small intestine against potentially harmful, oxidative effects of CuNPs by intensifying the intestinal barrier.
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Nsereko, V. L., K. A. Beauchemin, D. P. Morgavi, L. M. Rode, A. F. Furtado, T. A. McAllister, A. D. Iwaasa, W. Z. Yang et Y. Wang. « Effect of a fibrolytic enzyme preparation from Trichoderma longibrachiatum on the rumen microbial population of dairy cows ». Canadian Journal of Microbiology 48, no 1 (1 janvier 2002) : 14–20. http://dx.doi.org/10.1139/w01-131.
Texte intégralRésumé :
The effects of supplementing a dairy cow diet with incremental levels of a fibrolytic enzyme preparation (preparation B) from Trichoderma longibrachiatum on the rumen microbial population were investigated. Two cows fitted with rumen cannulae were each fed a diet containing barley-based concentrate (52%), maize silage (29%), and chopped alfalfa hay (19%), supplemented with 0, 1, 2, 5, or 10 L of preparation B per tonne of dry matter (DM). Preparation B stimulated numbers of total viable bacteria in a quadratic manner (P < 0.05), to approximately 230, 330, 390, and 250% at 1, 2, 5, and 10 L·t1 DM, respectively. Preparation B increased the numbers of cellobiose-utilizing (P < 0.01), xylanolytic (P < 0.05), and amylolytic bacteria (P < 0.05), but had no effect (P > 0.05) on numbers of cellulolytic bacteria. However, when bacterial numbers enumerated on each substrate were expressed as a proportion of total viable bacterial numbers, only cellobiose utilizers were stimulated, and this stimulation was limited to the 1 L·t1 DM level of preparation B (P < 0.05). The results of this study demonstrate that the inclusion of an exogenous fibrolytic enzyme preparation in dairy cow diets increased the numbers of rumen bacteria that utilize hemicelluloses and secondary products of cellulose digestion.Key words: rumen, fibrolytic enzymes, cellulase, xylanase, cellulolytic, xylanolytic.
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Halbur, Joseph, Jinsu Hong, Sara Llamas-Moya, Tri Duong, Mark J. Bertram, Amy L. Petry et Eric Weaver. « 158 Nutrient digestibility in growing pigs fed a corn distiller’s dried grains with soluble-based diet with multi-enzyme supplementation ». Journal of Animal Science 102, Supplement_2 (1 mai 2024) : 93–94. http://dx.doi.org/10.1093/jas/skae102.105.
Texte intégralRésumé :
Abstract Dietary enzyme supplementation may enhance the digestibility and utilization of non-starch components in fiber-rich feedtuffs which are increasingly used in swine diets. A xylanase/cellulase enzyme product (ENZ) was previously shown to increase the digestibility of nutrients and energy in growing pigs fed a corn-SBM diet with 30% corn dried distiller’s grains with solubles (cDDGS). To better elucidate the effects of ENZ on these components, further analysis was conducted on the fiber, non-starch polysaccharide, and ash components. A total of 12 ileal-cannulated pigs [initial body weight (BW) = 31.7 kg ± 3.04] were housed in individual metabolic crates for 21 d (period 1) and subsequently transferred to individual floor pens for an additional 28 d (period 2). These animals were assigned to 2 diets (n = 6) in a completely randomized design (CRD). The diets contained the main ingredients corn, soybean meal and cDDGS (30%) without (CON) or with ENZ supplementation. The inclusion rate of the ENZ (proprietary xylanase/cellulase product, Kerry Inc.) was 200 g/ton. Feed was formulated to 1.15% SID lysine and met or exceeded nutrient requirements for growing pigs (NRC, 2012). The diets were fed to pigs at three times maintenance energy requirement based on BW, which was assessed at 2 wk intervals throughout the study. The diets contained 0.3% titanium dioxide as an indigestible marker. In period 1, pigs had 14 d of adaptation, followed by 4 d of fecal and urine collection using the total collection method and 2 d of ileal digesta collection. In period 2, pigs had 23 days of adaptation, followed by 2 d of fecal collection and 2 d of ileal digesta collection. Data were analyzed as a CRD, using pig as the experimental unit and enzyme supplementation as the main effect. The ATTD of total NSP and galactose tended to improve in both periods 1 and 2. As consistent responses were observed in periods 1 and 2 and the ENZ X period interaction was not significant, the data from these time periods were combined for analysis. ENZ supplementation improved (P < 0.05) the ATTD of total NSP and galactose. Also, ENZ tended to improve (P < 0.10) the ATTD of cellulose and glucose from NSP. ENZ addition also increased the ATTD of calcium (P < 0.05) and tended to increase the ATTD of phosphorus (P < 0.10). In conclusion, supplementation of a corn-SBM-30% cDDGS diet with a multi-carbohydrase containing cellulase increased the ATTD of fiber, NSP and calcium in growing pigs. Novel enzymes represent a useful strategy to better utilize the nutrients in lower energy feedstuffs in monogastric animals.
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Shimizu, Jun, Masahide Oka, Keita Kudoh, Masahiro Wada, Toshichika Takita, Satoshi Innami, Tadahiro Tadokoro et Akio Maekawa. « Effects of a Partially Hydrolyzed Curdlan on Serum and Hepatic Cholesterol Concentration, and Cecal Fermentation in Rats ». International Journal for Vitamin and Nutrition Research 72, no 2 (1 mars 2002) : 101–8. http://dx.doi.org/10.1024/0300-9831.72.2.101.
Texte intégralRésumé :
A significant reduction was observed for serum and hepatic cholesterol concentrations in the rats fed diet containing a 5% partially hydrolyzed curdlan (PHCD), whereas only the hepatic cholesterol concentration was decreased in the curdlan (CD)-fed rats. The cecal contents in the CD group contained a significantly larger amount of short-chain fatty acids, but not those in the PHCD group. CD, but not PHCD, significantly increased the population of cecal bifidobacteria. From the in vitro fermentation test with cecal contents from cellulose powder (CP) and CD-fed rats, PHCD proved to be easily fermented by both cecal contents; incidentally CD was more susceptible to the cecal contents from CD-fed rats than to those from CP-fed rats. These results suggest that PHCD is involved in the modulation of lipid metabolism and intestinal microflora through a different manner from the native CD in rats.
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Bégin, F., C. Vachon, J. D. Jones, P. J. Wood et L. Savoie. « Effect of dietary fibers on glycemia and insulinemia and on gastrointestinal function in rats ». Canadian Journal of Physiology and Pharmacology 67, no 10 (1 octobre 1989) : 1265–71. http://dx.doi.org/10.1139/y89-201.
Texte intégralRésumé :
The effects of purified and semipurified dietary fiber supplements on glycemia and insulinemia were measured simultaneously with their effects on digestive tract function in the rat. An insoluble fiber (cellulose) and four soluble fibers (guar gum, carboxymethylcellulose, mustard mucilage, and oat β-glucan) were added separately to a fiber-free solid diet and fed to Sprague–Dawley rats for 10 days. Guar gum and oat β-glucan reduced the food intake, whereas cellulose increased it. Guar gum reduced weight gain. Cellulose increased the protein efficiency ratio. After a 13-h fast, glycemia and insulinemia were measured 45, 90, 210, and 360 min after the beginning of a voluntary short meal. Addition of fibers did not change the glycemic response, but soluble fibers significantly decreased insulinemia 45 min after the meal. All fibers significantly delayed gastric emptying, cellulose and mustard mucilage being the most effective. Dry matter contents of the small intestine were increased especially by guar gum and oat β-glucan. All fibers seemed to slow down small intestinal transit and decreased intestinal absorption. In the present experimental situation, both gastric and intestinal components played a role in the hypoinsulinic effect of dietary fibers. The intestinal component appeared to be more determinant for all soluble fibers, except mustard mucilage where the gastric component was more important.Key words: dietary fibers, glycemia, insulinemia, gastrointestinal function, digestion.
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Ndou, Saymore Petros, Elijah Kiarie, Maria Walsh, Cornelis de Lange et C. Martin Nyachoti. « 162 The interactions between dietary fiber and lipid sources alter the predicted production and absorption of caecal and colorectal volatile fatty acids in growing pigs ». Journal of Animal Science 97, Supplement_2 (juillet 2019) : 91. http://dx.doi.org/10.1093/jas/skz122.165.
Texte intégralRésumé :
Abstract A combination of in vivo and in vitro fermentation methodologies was used to determine the interactive effects of dietary fiber (DF) and lipid types on volatile fatty acids (VFA) production and absorption, and organic matter (OM) fermentability in the cecum and colorectal tract of pigs. Eight ileal- and caecal-cannulated Yorkshire barrows were fed either pectin- or cellulose-containing diets that were supplemented with either corn oil or beef tallow in two independent Youden squares with a 2×2 factorial arrangement of treatments (n = 6). Ileal and caecal digesta were collected, freeze-dried and fermented using inoculum from fresh caecal digesta and feces, respectively, to determine VFA production and absorption, and fermentability of OM. There were interactions (P < 0.001) between DF and lipid types observed in which the addition of corn oil increased the quantity of caecal and colorectal acetic acid production and caecal acetic absorption, caecal butyric production, predicted caecal OM fermentability, and the predicted colorectal propionic acid in pectin diets but did not have effects in cellulose diets. The addition of beef tallow increased (P < 0.001) the production of caecal butyric and propionic acids during in vitro fermentation in cellulose diets and fermentability of OM in pectin diets. The interactions between DF and lipids on gastrointestinal fermentation largely depends on the degree of saturation of fatty acids in dietary lipids. The addition of beef tallow selectively decreased the production and absorption of individual SCFA in pectin and cellulose diets but increased caecal butyric and propionic acid production in cellulose diets and the fermentability of OM in pectin diets.
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Marounek, Milan, Zdeněk Volek, Eva Skřivanová, Jan Tůma et Dagmar Dušková. « Comparative effect of amidated pectin and psyllium on cholesterol homeostasis in rats ». Open Life Sciences 5, no 3 (1 juin 2010) : 299–303. http://dx.doi.org/10.2478/s11535-010-0014-4.
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AbstractThe effects of amidated pectin and psyllium on serum, hepatic and faecal cholesterol concentration were compared in female rats fed diets supplemented with palm fat and cholesterol at 50 and 10 g/kg, respectively. Control rats were fed a diet supplemented with cellulose at 60 g/kg. In treated rats, cellulose was replaced with either amidated pectin or psyllium. Amidated pectin and psyllium intake significantly decreased serum cholesterol from 3.41 μmol/ml (control) to 1.68 and 2.04 μmol/ml, respectively, and hepatic cholesterol from 31.9 μmol/g (control) to 7.2 and 9.0 μmol/g, respectively. Histology with lipid-staining Sudan Black B revealed that liver tissue from control rats was infiltrated with lipids, but staining was absent in livers of treated rats. No hepatic pathophysiology was apparent in treated rats. Amidated pectin and psyllium intake significantly increased faecal fat content. Faecal cholesterol content was significantly increased in rats that were fed amidated pectin, and non-significantly increased in rats that were fed psyllium. Body weight and food intake did not differ among treatment groups. In conclusion, amidated pectin, a novel sequestrant of sterols, demonstrated a similar effect on rat serum and hepatic cholesterol concentration to psyllium, which is a well-established hypocholesterolaemic agent.
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Buddington, Randal K., Karyl K. Buddington et Greg D. Sunvold. « Influence of fermentable fiber on small intestinal dimensions and transport of glucose and proline in dogs ». American Journal of Veterinary Research 60, no 3 (1 mars 1999) : 354–58. http://dx.doi.org/10.2460/ajvr.1999.60.03.354.
Texte intégralRésumé :
Abstract Objective To determine whether intestinal dimensions and nutrient absorption are influenced by different types of dietary fiber. Animals 10 adult Beagles of both sexes. Procedure Dogs were randomly assigned to 2 groups and fed a diet with fermentable fibers (beet pulp and oligofructose) or a nonfermentable fiber (cellulose) for 6 weeks. Effects of the diets on small intestinal dimensions were measured, and transport rates for glucose and proline were determined. Kinetics of glucose and proline uptake were defined in the proximal and middle regions of the small intestine, respectively. Results Small intestines of dogs fed fermentable fiber had 28% more nominal surface area and 37% more mucosal mass, were 35% heavier, and had 95% higher capacity for carrier-mediated glucose uptake than those of dogs fed a diet with cellulose. Differences were more pronounced in the proximal portion of the intestine. Conclusions and Clinical Relevance Diets containing fermentable fibers increase small intestinal dimensions and the capacity for nutrient absorption in dogs. These changes may reduce the risk of enteric infections or aid in treatment of intestinal diseases, particularly those involving reduced nutrient absorption.(Am J Vet Res 1999;60:354–358)
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Illman, Richard J., David L. Topping, Kerin Dowling, Rodney P. Trimble, Gordon R. Russell et Gerald B. Storer. « Effects of solvent extraction on the hypocholesterolaemic action of oat bran in the rat ». British Journal of Nutrition 65, no 3 (mai 1991) : 435–43. http://dx.doi.org/10.1079/bjn19910102.
Texte intégralRésumé :
In adult male rats fed on a cholesterol-free synthetic diet, plasma cholesterol concentrations were lowest with oat bran, intermediate with cellulose and highest with wheat bran. Plasma triacylglycerols (TAG) were similar with wheat bran and cellulose but higher with oat bran. The concentrations and pools of caecal volatile fatty acids (VFA) were lowest with cellulose and equally higher with oat bran and wheat bran. Plasma VFA concentrations in the hepatic portal vein reflected those in caecal digesta and were unrelated to plasma cholesterol. Feeding oat bran after extraction with n-pentane gave plasma cholesterol concentrations similar to that found with wheat bran. Reconstitution of oat bran with extracted lipids did not restore the cholesterol-lowering effect. Addition of the extracted material to a wheat-bran diet had no effect on plasma cholesterol. Plasma TAG were higher with the oat bran and reconstituted-oatbran diets than with wheat-bran or cellulose diets. However, extracted oat bran+safflower oil gave similar TAG concentrations to that with wheat bran. These extractions and additions did not change caecal bile acid or neutral sterol concentrations. Effects of these diets on plasma cholesterol were unrelated to their tocotrienol or tocopherol content. Addition of n-pentane to oat bran followed by evaporation of solvent gave plasma cholesterol concentrations that were significantly higher than untreated oat bran but lower than similarly treated wheat bran. It is concluded that oat bran affects cholesterol metabolism through a pentane-soluble component as well as non-starch polysaccharides. It appears that the activity of this lipid is not transferable by simple addition of the solvent extract to the whole diet.