907 resultados para FEEDS
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In the present study, natural occurrence of fungi and aflatoxin B1 (AFB1) in pellet feed and feed ingredients used for rainbow trout was investigated with emphasis to Aspergillus section Flavi members and medicinal plants inhibitory to Aspergillus growth and/or AF production. The feed samples were cultured on the standard isolation media including dichloran rosebengal chloramphenicol agar (DRCA) and Aspergillus flavus/parasiticus agar (AFPA) for 2 weeks at 28 °C. Identification of fungal isolates was implemented based on the macro- and microscopic morphological criteria. AFs were detected using high performance liquid chromatography (HPLC). Based on the results obtained, a total of 109 fungal isolates were identified of which Aspergillus was the prominent genus (57.0%), followed by Penicillium (12.84%), Absidia (11.01%) and Pseudallscheria (10.10%). The most frequent Aspergillus species was A. flavus (60.66%) isolated from all the feed ingredients as well as pellet feed. Among 37 A. flavus isolates, 19 (51.35%) were able to produce AFB1 on yeast extract-sucrose (YES) broth in the range of 10.2 to 612.8 [tg/g fungal dry weight. HPLC analyses of trout feed showed that pellet feed and all feed ingredients tested except gluten were contaminated with different levels of AFB1 in the range of 1.83 to 67.35 lig/kg. In order to finding natural inhibitors of fungal growth and/or AF production, essential oils (EOs) and extracts of 49 medicinal plants were studied against an aflatoxin-producing A. parasiticus using a microbioassay technique. The EOs was analyzed by gas chromatography/mass spectrometry (GC/MS). Based on the results obtained, Achillea millefolium sub sp. elborsensis, Ferula gummosa, Mentha spicata, Azadirachta indica, Conium maculatum and Artemisia dracunculus remarkably inhibited A. parasiticus growth without affecting AF production by the fungus. Besides of Thymus vulgaris and Citrus aurantifolia, the EO of Foeniculum vulgare significantly inhibited both fungal growth (-70.0%) and AFs B1 and G1 (-99.0%) production. The EO of Carum carvi and ethyl acetate extract of Platycladus orientalis suppressed AFs B1 and G1 by more than 90.0%, without any obvious effect on fungal growth. The IC50 values of bioactive plants for AFs B1 and G1 were determined in the ranges of 90.6 to 576.2 and 2.8 to 61.9 µg/ml, respectively. Overall, results of the present study indicate the importance of AF contamination of trout feed as a risk factor for fish farming and thus, an urgent necessity for constant monitoring of trout feed for any unacceptable levels of AF contamination. Likewise, antifungal activities of bioactive plants introduced here would be an important contribution to explain the use of these plants as effective antimicrobial candidates to protect feeds from toxigenic fungus growth and subsequent AF contamination.
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Bacillus amyloliquefaciens H57 is a bacterium isolated from lucerne for its ability to prevent feed spoilage. Further interest developed when ruminants fed with H57-inoculated hay showed increased weight gain and nitrogen retention relative to controls, suggesting a probiotic effect. The near complete genome of H57 is ~3.96 Mb comprising 16 contigs. Within the genome there are 3,836 protein coding genes, an estimated sixteen rRNA genes and 69 tRNA genes. H57 has the potential to synthesise four different lipopeptides and four polyketide compounds, which are known antimicrobials. This antimicrobial capacity may facilitate the observed probiotic effect.
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Social networks rely on concepts such as collaboration, cooperation, replication, flow, speed, interaction, engagement, and aim the continuous sharing and resharing of information in support of the permanent social interaction. Facebook, the largest social network in the world, reached, in May 2016, the mark of 1.09 billion active users daily, draining 161.7 million hours of users’ attention to the website every day. These users share 4.75 billion units of content daily. The research presented in this dissertation aims to investigate the management of knowledge and collective intelligence, from the introduction of mechanisms that aim to enable users to manage and organize current information in the feeds from Facebook groups in which they participate, turning Facebook into a collective knowledge and information management device that goes far beyond mere interaction and communication among people. The adoption of Design Science Research methodology is intended to instill the "genes" of collective intelligence, as presented in the literature, in the computational artifact being developed, so that intelligence can be managed and used to create even more knowledge and intelligence to and by the group. The main theoretical contribution of this dissertation is to discuss knowledge management and collective intelligence in a complementary and integrated manner, showing how efforts to obtain one also contribute to leveraging the other.
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The sohal surgeonfish or sohal tang, Acanthurus sohal, is a Red Sea endemic which grows to 16 in (40 cm) in the wild. Its striking blue and white horizontal stripes have made it what many consider the 'poster fish' for the Red Sea reef environment. It is a valued aquarium fish. A common species found in seaward edges of reefs exposed to surge. Aggressive and territorial. Feeds on various kinds of algae, mainly Sargassum, and fine filamentous green algae. Caught with nets; traps and occasionally by trawls.
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Chrysiptera unimaculata, an algivorous species also living on the coral reef flat and being territorial but not considered as a strict farmer in this location. Maximum length is 8 cm in Persian Gulf. It is living in close association with macrophytes. Adults are found solitarily or in small groups among coastal algal reefs, rubble or over open beach-rock of reef flats exposed to moderate surge and feeds mainly on benthic algae. C. unimaculata is oviparous, distinct pairing during breeding. Eggs are demersal and adhere to the substrate. Males guard and aerate the eggs.
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Os contornos de um mundo em mudança e a evolução do pensamento há muito que se afastaram dos conceitos de identidades unas e imutáveis. A própria aceitação da mutabilidade traduz-se também nos cenários das vastas possibilidades para os fenómenos identitários à escala global. Também por isso, e mais do que nunca, se revela preponderante a reflexão sobre tais fenómenos identitários e a compreensão da sua intervenção e pertinência nas constantes reconfigurações sociais da atualidade. Esse será o universo do presente trabalho, onde serão auscultadas atuais conceções identitárias e o seu lugar no caso português. Este estudo configura-se, portanto, a partir de objetivos centrais bem delimitados: identificar e caracterizar a eventual existência de identidades regionais em Portugal, no caso particular dos territórios associados a Viseu. Este ponto de partida surge da análise da frequente cartografia das identidades territoriais na realidade portuguesa, bem como da continuidade de anteriores estudos do autor. Com efeito, verifica-se que frequentemente se definem duas grandes tipologias identitárias no que concerne à relação com o território: a local e a nacional. Tal posição surge em aberta contradição com os discursos mediáticos recorrentes onde a constante presença de um discurso de matriz regional obriga à dúvida inevitável. Nesse sentido, falando-se de região, foi necessário percorrer os conceitos de limite e de fronteira que a delimitam e lhe conferem sentido, indagando-se sobre o lugar da sua criação e da sua vivência. Assim, o trabalho orientou-se em dois grandes sentidos iniciais: o do levantamento da ação delimitadora do Estado, tido como autor das demarcações regionais em Portugal e o da auscultação da produção discursiva dos media regionais, agentes e expressão da identidade regional. A segunda dimensão obrigaria a um estudo aturado sobre a imprensa regional, objeto essencial do presente trabalho e a partir do qual será possível alcançar conclusões validáveis para o período entre 1959 e 2011. É então pelo cruzamento das duas dimensões referidas que se surpreende a existência de traços identitários regionais bem vincados, profundamente arreigados ao discurso do Estado Novo, raramente correspondendo aos intentos de delimitação das sucessivas iniciativas governamentais posteriores que, desse modo, revelam também um profundo distanciamento desse território que insistentemente vão dividindo. Entre o discurso eivado de simbolismo – embora centralista – do Estado Novo e as denominações técnicas – embora com o propósito de promover a descentralização do poder – da democracia, o discurso identitário da imprensa regional de Viseu alimenta-se ainda hoje do primeiro. Não porque vise os seus objetivos, mas porque é o que melhor caracteriza uma identidade relativamente pacificada: sempre pronta a recorrer ao passado beirão para afirmar as suas diferenças, sem no entanto pôr em causa o espírito da Nação; sempre pronta a denunciar o centralismo de Lisboa, esquecendo embora que foi esse centralismo que outrora lhe atribuiu a característica da genuinidade de, o que quer que seja, ser português.
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Aim This systematic review aimed at examining the best available evidence on the effectiveness of community-based nutrition education in improving the nutrition status of under five children in developing countries. Methods A systematic search of the literature was conducted utilising the following data bases: Cumulative Index to Nursing and Allied Health Literature (CINAHL), EMBASE, Medline, and Web of Knowledge. 9 studies were identified for the critical appraisal process. The Joanna Briggs Institute (JBI) critical appraisal check-list for experimental studies was utilised and two reviewers conducted the appraisal process independently. 7 studies were included for this review and data was extracted using the JBI data extraction form for experimental studies. The extracted data was heterogeneous as such narrative synthesis was conducted. Results The nutritional status of children in all studies improved and this was evidenced by increases in weight, height, mid upper arm circumference and reduced morbidity. Key messages about education were age at introduction of complementary foods, nutrition value on different types of feeds found locally and frequency of feeding the children. However, there were varied Results regarding the effects of the intervention on the nutrition status of children. This was attributed by differences in implementers’ characteristics, different intervention strategy and intensity, difference in age of the children at enrolment, pre-existing children’s growth and nutritional status and follow-up periods. In addition to home visiting, conducting group meetings of care givers and community leaders, providing education twice a week and use of cooking demonstrations have shown that they produce highly significant findings. Conclusion The evidence from the identified studies suggests that community- based nutrition education improves the nutrition status of under-five children in developing countries.
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Background Nutritional support is a recognized determinant of outcome in critically ill patients. Development of critical care services in low-income countries has not been accompanied by certain appropriate ancillary services and interventions, such as adequate nutritional support. This study was designed to investigate the experiences of health professionals who have provided nutritional supportive care to critically ill patients admitted to two major central hospitals in Malawi, with the aim of identifying the common practices in nutritional support in these settings. Materials and Methods A cross-sectional study in which 50 health professionals working in intensive care and high dependency units, admitting both adult and pediatric patients, were interviewed using a semi-structured questionnaire. Data were coded and then analyzed using SPSS version 16.0. Responses between the two hospitals were compared using Fisher’s exact test. Results There was no difference in the composition of respondents from the two hospitals. About 60% of respondents had had experience with nutritional supplementation in their patients—mainly enteral. The most commonly used formulations were the “ready-to-use therapeutic feeds,” followed by modified milk. A high percentage of respondents (40%) reported having used dextrose solution as the sole nutritional supplement. Lack of in-service training, nonexistent nutrition protocols pertaining to acutely and critically ill patients, and a lack of clinical nutritionists were the major challenges identified. Conclusion Knowledge of nutrient supplementation was poor among the respondents. The use of ready-to-use therapeutic feeds was quite common, although there is no evidence of its effectiveness in care of acutely critically ill patients. There is a need to establish nutritional support teams in these tertiary hospitals. Clinical nutritionists would ideally help train and play leadership roles in such teams, who would be responsible for assessing patients for their nutritional needs, and ensuring that the feeds provided to patients are appropriate and adequate for their needs.
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Foram estudados os hábitos alimentares da raia-viola-de-focinho-curto, Zapteryx brevisrostris, com base em 382 espécimes coletados no litoral norte de São Paulo, sudeste do Brasil. A dieta mostrou predominância de crustáceos (carídeos e anfípodes), anelídeos poliquetos e ocasionalmente pequenos peixes, sipunculídeos e cefalópodes. A dieta de machos e fêmeas mostrou-se similar, entretanto, juvenis, subadultos e adultos demonstraram diferenças na composição de presas. As frequências dos itens diferiram ao longo do ano, provavelmente influenciadas por fatores oceanográficos, embora, em geral, a espécie se alimente predominantemente de crustáceos e poliquetos.
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Nickel-containing catalysts are developed to oligomerize light olefins. Two nickel-containing zincosilicates (Ni-CIT-6 and Ni-Zn-MCM-41) and two nickel-containing aluminosilicates (Ni-HiAl-BEA and Ni-USY) are synthesized as catalysts to oligomerize propylene into C3n (C6 and C9) products. All catalysts oligomerize propylene, with the zincosilicates demonstrating higher average selectivities to C3n products, likely due to the reduced acidity of the Zn heteroatom.
To test whether light alkanes can be incorporated into this oligomerization reaction, a supported homogeneous catalyst is combined with Ni-containing zincosilicates. The homogeneous catalyst is included to provide dehydrogenation/hydrogenation functions. When this tandem catalyst system is evaluated using a propylene/n-butane feed, no significant integration of alkanes are observed.
Ni-containing zincosilicates are reacted with 1-butene and an equimolar propylene/1-butene mixture to study other olefinic feeds. Further, other divalent metal cations such as Mn2+, Co2+, Cu2+, and Zn2+ are exchanged onto CIT-6 samples to investigate stability and potential use for other reactions. Co-CIT-6 oligomerizes propylene, albeit less effectively than Ni-CIT-6. The other M-CIT-6 samples, while not able to oligomerize light olefins, may be useful for other reactions, such as deNOx.
Molecular sieves are synthesized, characterized, and used to catalyze the methanol-to-olefins (MTO) reaction. The Al concentration in SSZ-13 samples is varied to investigate the effect of Al number on MTO reactivity when compared to a SAPO-34 sample with only isolated Si Brønsted acid sites. These SSZ-13 samples display reduced transient selectivity behavior and extended reaction lifetimes as Si/Al increases; attributable to fewer paired Al sites. MTO reactivity for the higher Si/Al SSZ-13s resembles the SAPO-34 sample, suggesting that both catalysts owe their stable reaction behavior to isolated Brønsted acid sites.
Zeolites CHA and RHO are prepared without the use of organic structure-directing agents (OSDAs), dealuminated by steam treatments (500°C-800°C), and evaluated as catalysts for the MTO reaction. The effects of temperature and steam partial pressure during steaming are investigated. X-ray diffraction (XRD) and Ar physisorption show that steaming causes partial structural collapse of the zeolite, with degradation increasing with steaming temperature. 27Al MAS NMR spectra of steamed materials reveal the presence of tetrahedral, pentacoordinate, and hexacoordinate aluminum.
Proton forms of as-synthesized CHA (Si/Al=2.4) and RHO (Si/Al=2.8) rapidly deactivate under MTO testing conditions (400°C, atmospheric pressure). CHA samples steamed at 600°C performed best among samples tested, showing increased olefin selectivities and catalyst lifetime. Acid washing these steamed samples further improved activity. Reaction results for RHO were similar to CHA, with the RHO sample steamed at 800°C producing the highest light olefin selectivities. Catalyst lifetime and C2-C3 olefin selectivities increase with increasing reaction temperature for both CHA-type and RHO-type steamed samples.
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The aquatic environment receives many contaminants that can induce damages at the molecular, biochemical, cellular and physiological levels. Centropomus parallelus, an important food resource for local populations, is a predator fish that feeds on small fishes and benthic invertebrates, thus being vulnerable to the bioconcentration and biomagnification processes. This study aimed to evaluate cytogenotoxic responses in erythrocytes from C. parallelus juveniles collected in the Cananeia and Sao Vicente estuaries, both in winter and in summer. After anesthesia, blood samples were collected by caudal puncture. Blood smears were prepared on glass slides and stained with May-Grunwald-Giemsa dye. Two thousand cells were analyzed per slide (1000x), and nuclear abnormalities (NA) and micronuclei (MN) were scored. The Sao Vicente sample showed MN and NA frequencies (%/1000 cells) of 0.325 and 3.575, in winter, and of 0.125 and 2.935 in summer respectively; the Cananeia sample showed frequencies of 0.0325 and 0.03, in winter, and of 0.065 and 0.355 in summer, respectively. The rates found in Sao Vicente were significantly higher than those found in Cananeia, evidencing that the levels of pollution in that estuary were high enough to induce genetic damages.
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Dissertação de Mestrado em Engenharia Zootécnica / Produção Animal
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Stable isotope analyses were applied to explore the relative dietary nitrogen contributions from fish meal and pea meal (Pisum sativum) to muscle tissue of Pacific white shrimp postlarvae (141 ± 31 mg) fed low protein diets having different proportions of both ingredients as the sole dietary protein sources. A negative control diet was formulated to contain 100% pea meal and six more isoproteic diets to have decreasing levels of pea meal-derived nitrogen: 95%, 85%, 70%, 55%, 40% and 0% of the initial level. Growth rates were negatively correlated to dietary pea protein inclusion due to progressive essential amino acid deficiencies (sulphur amino acids, threonine, lysine, histidine). The nitrogen turnover rate significantly increased in muscle tissue of shrimps fed diets having high levels of pea meal; however, contrary to observations from a previous study using soy protein, the relative contributions of dietary nitrogen from pea meal to shrimp muscle tissue were equal or higher than expected contributions established by the dietary formulations. Results highlight the effectiveness of stable isotope analysis in assessing the nutritional contributions of alternative ingredients for aquaculture feeds and the potential suitability of pea as a source of protein (provided the diets are nutritionally balanced)
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Due to lack of information on the use of non-protein energy sources in diets for pacu (Piaractus mesopotamicus), a 2 x 2 x 3 factorial experiment was conducted to evaluate the performance and digestibility of 12 diets containing approximately two crude protein (CP; 220 and 250 g kg(-1)), two lipid (40 and 80 g kg(-1)) and three carbohydrate levels (410, 460 and 500 g kg(-1)). The pacu juveniles-fed diets containing 220 g kg(-1) CP did not respond (P > 0.05) to increased dietary lipid and carbohydrate levels, but the fish-fed diets containing 250 g kg(-1) CP showed a better feed conversion ratio. There were interactions in weight gain (WG), specific growth rate (SGR), crude protein intake (CPI) and feed conversion rate (FCR) dependent on dietary carbohydrate and lipid levels, showing positive effects of increasing carbohydrate levels only for fish-fed diets containing 80 g kg(-1) lipid level. However, when the diets contained 40 g kg(-1) lipid, the best energy productive value (EPV) results were obtained at 460 g kg(-1) carbohydrate. A higher usage of lipids (80 g kg(-1)) reduced CPI and was detrimental to protein [apparent digestibility coefficient (ADC)(CP)] and energy (ADC(GE)), but did not affect growth. The ADC(GE) improved proportionally as dietary carbohydrate levels increased (P < 0.05), increasing the concentration of digestible energy. In addition, the WG, CPI, ADC(GE) results showed best use of the energy from carbohydrates when dietary protein level was 250 g kg(-1) CP. The utilization of 250 g kg(-1) CP in feeds for juvenile pacu for optimal growth is suggested. Therefore, the optimum dietary lipid and carbohydrate levels depend on their combinations. It can be stated that pacu uses carbohydrates as effectively as lipids in the maximization of protein usage, as long as it is not lower than 250 g kg(-1) CP or approximately 230 g kg(-1) digestible protein.