62 research outputs found

    Assessment of potato peel and agro-forestry biochars supplementation on in vitro ruminal fermentation

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    UIDB/50006/2020 UIDB/04033/2020 grant ref. PDE/BDE/114434/2016 DL 57/2016 -Norma transitória.Background. The awareness of environmental and socio-economic impacts caused by greenhouse gas emissions from the livestock sector leverages the adoption of strategies to counteract it. Feed supplements can play an important role in the reduction of the main greenhouse gas produced by ruminants-methane (CH4). In this context, this study aims to assess the effect of two biochar sources and inclusion levels on rumen fermentation parameters in vitro. Methods. Two sources of biochar (agro-forestry residues, AFB, and potato peel, PPB) were added at two levels (5 and 10%, dry matter (DM) basis) to two basal substrates (haylage and corn silage) and incubated 24-h with rumen inocula to assess the effects on CH4 production and main rumen fermentation parameters in vitro. Results. AFB and PPB were obtained at different carbonization conditions resulting in different apparent surface areas, ash content, pH at the point of zero charge (pHpzc), and elemental analysis. Relative to control (0% biochar), biochar supplementation kept unaffected total gas production and yield (mL and mL/g DM, pD0.140 and pD0.240, respectively) and fermentation pH (p D 0.666), increased CH4 production and yield (mL and mL/g DM, respectively, pD0.001) and ammonia-N (NH3-N, pD0.040), and decreased total volatile fatty acids (VFA) production (p < 0.001) and H2 generated and consumed (p ≤ 0.001). Biochar sources and inclusion levels had no negative effect on most of the fermentation parameters and efficiency. Acetic.propionic acid ratio (pD0.048) and H2 consumed (pD0.019) were lower with AFB inclusion when compared to PPB. Biochar inclusion at 10% reduced H2 consumed (p < 0.001) and tended to reduce total gas production (pD0.055). Total VFA production (pD0.019), acetic acid proportion (pD0.011) and H2 generated (pD0.048) were the lowest with AFB supplemented at 10%, no differences being observed among the other treatments. The basal substrate affected most fermentation parameters independently of biochar source and level used. Discussion. Biochar supplementation increased NH3-N content, iso-butyric, iso-valeric and valeric acid proportions, and decreased VFA production suggesting a reduced energy supply for microbial growth, higher proteolysis and deamination of substrate N, and a decrease of NH3-N incorporation into microbial protein. No interaction was found between substrate and biochar source or level on any of the parameters measured. Although AFB and PPB had different textural and compositional characteristics, their effects on the rumen fermentation parameters were similar, the only observed effects being due to AFB included at 10%. Biochar supplementation promoted CH4 production regardless of the source and inclusion level, suggesting that there may be other effects beyond biomass and temperature of production of biochar, highlighting the need to consider other characteristics to better identify the mechanism by which biochar may influence CH4 production.publishersversionpublishe

    Effects of grass silage and soybean meal supplementation on milk production and milk fatty acid profiles of grazing dairy cows

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    Copyright © American Dairy Science Association, 2008.The effects of supplementation with grass silage and replacement of some corn in the concentrate with soybean meal (SBM) on milk production, and milk fatty acid (FA) profiles were evaluated in a replicated 4 × 4 Latin square study using 16 dairy cows grazing pasture composed of ryegrass, Kentucky bluegrass, and white clover. Each experimental period lasted for 3 wk. The 4 dietary treatments were PC, 20 h of access to grazing pasture, supplemented with 6 kg/d of corn-based concentrate mixture (96% corn; C); PCSB, 20 h of access to grazing pasture, supplemented with 6 kg/d of corn- and SBM-based concentrate mixture (78% corn and 18% SBM; CSB); SC, 7 h of access to grazing pasture during the day and 13 h of ad libitum access to grass silage at night, supplemented with 6 kg/d of C concentrate; and SCSB, 7 h of access to grazing pasture during the day and 13 h of ad libitum access to grass silage at night, supplemented with 6 kg/d of CSB concentrate. The concentrate mixtures were offered twice each day in the milking parlor and were consumed completely. Grass silage supplementation reduced dietary crude protein and concentration of total sugars, and dietary SBM inclusion increased dietary crude protein concentration and decreased dietary starch concentration. Milk yield and energy-corrected milk were increased by SBM supplementation of cows with access to grass silage. Milk protein concentration was lower in cows offered grass silage, regardless of whether SBM was fed. Dietary SBM inclusion tended to increase milk fat concentration. Plasma urea N was reduced by silage feeding and increased by SBM supplementation. Supplementation with grass silage overnight could represent a useful strategy for periods of lower pasture availability. Dietary inclusion of SBM in solely grazing cows had no effects on milk production and composition, exacerbated the inefficient capture of dietary N, and increased diet cost. Grass silage supplementation affected milk FA profiles, increasing both the FA derived from de novo synthesis and those derived from rumen microbial biomass, and decreasing the sum of C18 FA (mostly derived from diet or from mobilization of adipose tissue reserves). Milk fat concentrations of conjugated linoleic acid cis-9, trans-11, vaccenic acid (18:1 trans-11), and linolenic acid (18:3n-3) were unaffected by grass silage supplementation, suggesting that partial replacement of pasture by unwilted grass silage does not compromise the dietary quality of milk fat for humans

    Squid meal and shrimp hydrolysate as novel protein sources for dog food

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    The world’s growing pet population is raising sustainability and environmental concerns for the petfood industry. Protein-rich marine by-products might contribute to mitigating negative environmental effects, decreasing waste, and improving economic efficiency. The present study evaluated two marine by-products, squid meal and shrimp hydrolysate, as novel protein sources for dog feeding. Along with the analysis of chemical composition and antioxidant activity, palatability was evaluated by comparing a commercial diet (basal diet) and diets with the inclusion of 150 g kg−1 of squid meal or shrimp hydrolysate using 12 Beagle dogs (2.2 ± 0.03 years). Two in vivo digestibility trials were conducted with six dogs, three experimental periods (10 days each) and three dietary inclusion levels (50, 100 and 150 g kg−1) of squid meal or shrimp hydrolysate in place of the basal diet to evaluate effects of inclusion level on apparent total tract digestibility (ATTD), metabolizable energy content, fecal characteristics, metabolites, and microbiota. Both protein sources presented higher protein and methionine contents than ingredients traditionally used in dog food formulation. Shrimp hydrolysate showed higher antioxidant activity than squid meal. First approach and taste were not affected by the inclusion of protein sources, but animals showed a preference for the basal diet. Effects on nutrient intake reflected the chemical composition of diets, and fecal output and characteristics were not affected by the increasing inclusion levels of both protein sources. The higher ATTD of dry matter, most nutrients and energy of diets with the inclusion of both by-products when compared to the basal diet, suggests their potential to be included in highly digestible diets for dogs. Although not affected by the inclusion level of protein sources, when compared to the basal diet, the inclusion of squid meal decreased butyrate concentration and shrimp hydrolysate increased all volatile fatty acids, except butyrate. Fecal microbiota was not affected by squid meal inclusion, whereas inclusion levels of shrimp hydrolysate significantly affected abundances of Oscillosperaceae (UCG-005), Firmicutes and Lactobacillus. Overall, results suggest that squid meal and shrimp hydrolysate constitute novel and promising protein sources for dog food, but further research is needed to fully evaluate their functional value

    Currículo de la pre secundaria en Timor Oriental y su articulación con la secundaria general

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    Problemas herdados nas últimas décadas conduziram Timor-Leste a reestruturar os currículos do ensino pré-secundário – EPS – e do secundário geral – ESG.1 Atendendo à importância de uma adequada articulação vertical ao longo dos ciclos de escolaridade e diante do cumprimento de uma primeira edição completa do EPS, importa estudar se tal currículo está alinhado com o do ESG, em particular no que respeita às Ciências e Tecnologia. Este artigo centra-se na análise do currículo do EPS e na avaliação da sua articulação com o do ESG. Não obstante existam décalages entre o currículo prescrito, o implementado e o apropriado, é relevante haver sintonia no nível dos currículos para uma educação e formação de boa qualidade, fundamentais à consecução dos Objetivos de Desenvolvimento do Milénio.Problems inherited from the last decades have led Timor-Leste to restructure its pre-secondary – EPS – and general secondary – ESG – curricula. Considering the importance of an adequate vertical articulation throughout the schooling cycles and before the conclusion of the first complete edition of the EPS, it is necessary to study if such a curriculum is aligned with the one of the ESG, in particular with regard to Science and Technology. This article focuses on the analysis of the EPS curriculum and the evaluation of its articulation with the one of ESG. Notwithstanding the décalages among the prescribed, the implemented and the appropriate curricula, it is relevant to have a fine-tuning at this level to ensure good quality education and training, essential to achieve the millennium development goals.Des problèmes hérités des dernières décennies ont conduit le Timor-Oriental à restructurer ses programmes d’enseignement présecondaire – EPS –, ainsi que ceux de l’enseignement secondaire général – ESG. Compte tenu de l’importance d’une bonne articulation verticale tout au long des cycles scolaires etvu qu’une première édition complète de l’EPS a déjà été mise en place, il est important de vérifier si ce programme s’aligne bien à celui de l’ESG, particulièrement en ce qui concerne les Sciences et la Technologie. Cet article se concentre sur l’analyse du programme de l’EPS et sur l’évaluation de son articulation avec celui de l’ESG. Nonobstant certains décalages entre le programme prescrit, celui qui a été mis en œuvre et celui qui est approprié, il est nécessaire que les programmes soient en phase pour atteindre une éducation et une formation de qualité, fondamentales pour la réalisation des Objectifs du Millénaire pour le Développement.Problemas heredados en las últimas décadas hicieron que Timor Oriental reestructurase los currículos de la educación pre secundaria – EPS – y de la secundaria general – ESG. En función de la importancia de una adecuada articulación vertical a lo largo de los ciclos de escolaridad y frente al cumplimiento de una primera edición completa do EPS, importa estudiar si tal currículo está alineado con el del ESG, en particular en lo que concierne a las Ciencias y Tecnología. Este artículo se centra en el análisis del currículo del EPS y en la evaluación de su articulación con el del ESG. No obstante la existencia de décalages entre el currículo prescrito, el implementado y el apropiado, es relevante que haya sintonía a nivel de los currículos para una educación y formación de calidad, fundamentales para la consecución de los Objetivos de Desarrollo del Milenio

    A commercial blend of macroalgae and microalgae promotes digestibility, growth performance, and muscle nutritional value of European seabass (Dicentrarchus labrax L.) juveniles

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    Algae can leverage aquaculture sustainability and improve the nutritional and functional value of fish for human consumption, but may pose challenges to carnivorous fish. This study aimed to evaluate the potential of a commercial blend of macroalgae (Ulva sp. and Gracilaria gracilis) and microalgae (Chlorella vulgaris and Nannochloropsis oceanica) in a plant-based diet up to 6% (dry matter basis) on digestibility, gut integrity, nutrient utilization, growth performance, and muscle nutritional value of European seabass juveniles. Fish (11.3 ± 2.70 g) were fed with isoproteic, isolipidic, and isoenergetic diets: (i) a commercial-type plant-based diet with moderate fishmeal (125 g kg−1 DM basis) and without algae blend (control diet; Algae0), (ii) the control diet with 2% algae blend (Algae2), (iii) the control diet with 4% algae blend (Algae4), and (iv) the control diet with 6% algae blend (Algae6) for 12 weeks. The digestibility of experimental diets was assessed in a parallel study after 20 days. Results showed that most nutrients and energy apparent digestibility coefficients were promoted by algae blend supplementation, with a concomitant increase in lipid and energy retention efficiencies. Growth performance was significantly promoted by the algae blend, the final body weight of fish fed Algae6 being 70% higher than that of fish fed Algae0 after 12 weeks, reflecting up to 20% higher feed intake of algae-fed fish and the enhanced anterior intestinal absorption area (up to 45%). Whole-body and muscle lipid contents were increased with dietary algae supplementation levels by up to 1.79 and 1.74 folds in Algae 6 compared to Algae0, respectively. Even though the proportion of polyunsaturated fatty acids was reduced, the content of EPA and DHA in the muscle of algae-fed fish increased by nearly 43% compared to Algae0. The skin and filet color of juvenile European seabass were significantly affected by the dietary inclusion of the algae blend, but changes were small in the case of muscle, meeting the preference of consumers. Overall results highlight the beneficial effects of the commercial algae blend (Algaessence®) supplementation in plant-based diets for European seabass juveniles, but feeding trials up to commercial-size fish are needed to fully assess its potential

    Detailed dimethylacetal and fatty acid composition of rumen content from lambs fed lucerne or concentrate supplemented with soybean oil

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    Articles in International JournalsLipid metabolism in the rumen is responsible for the complex fatty acid profile of rumen outflow compared with the dietary fatty acid composition, contributing to the lipid profile of ruminant products. A method for the detailed dimethylacetal and fatty acid analysis of rumen contents was developed and applied to rumen content collected from lambs fed lucerne or concentrate based diets supplemented with soybean oil. The methodological approach developed consisted on a basic/ acid direct transesterification followed by thin-layer chromatography to isolate fatty acid methyl esters from dimethylacetal, oxo- fatty acid and fatty acid dimethylesters. The dimethylacetal composition was quite similar to the fatty acid composition, presenting even-, odd- and branched-chain structures. Total and individual odd- and branched-chain dimethylacetals were mostly affected by basal diet. The presence of 18:1 dimethylacetals indicates that biohydrogenation intermediates might be incorporated in structural microbial lipids. Moreover, medium-chain fatty acid dimethylesters were identified for the first time in the rumen content despite their concentration being relatively low. The fatty acids containing 18 carbon-chain lengths comprise the majority of the fatty acids present in the rumen content, most of them being biohydrogenation intermediates of 18:2n26 and 18:3n23. Additionally, three oxo- fatty acids were identified in rumen samples, and 16-O-18:0 might be produced during biohydrogenation of the 18:3n23

    The institutions of archaic post-modernity and their organizational and managerial consequences: The case of Portugal

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    The long march of modernization of the Western societies tends to be presented as following a regular sequence: societies and institutions were pre-modern, and then they were modernized, eventually becoming post-modern. Such teleology may provide an incomplete or distorted narrative of societal evolution in many parts of the world, even in the ‘post-modern heartland’ of Western Europe, with Portugal being a case in point. The concept of archaic post-modernity has been developed by a philosopher, José Gil, to show how Portuguese institutions and organizations combine elements of pre-modernity and post-modernity. The notion of an archaic post-modernity is advanced in order to provide an alternative account of the modernization process, which enriches discussion of the varieties of capitalism. Differences in historical experiences create singularities that may be considered in the analysis of culture, management and organization
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