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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Formas de aplicação de zinco e molibdênio no feijoeiro /

Sanches, Marco Antonio, 1983- January 2010 (has links)
Orientador: Dirceu Maximino Fernandes / Banca: Hélio Grassi Filho / Banca: Edison Ulisses Ramos Junior / Resumo: A nutri„…o mineral do feijoeiro com macro e micronutrientes  fundamental para a sobreviv‡ncia, desenvolvimento afetando diretamente a produtividade. Os micronutrientes por sua vez s…o essenciais em pequenas quantidades, sendo sua corre„…o complexa, para que os nŠveis necessŒrios †s plantas sejam atendidos. Dentre esses micronutrientes, o Zn  um nutriente escasso em solos brasileiros, bem como o Mo que possui vital import“ncia, pois melhora o aproveitamento de N2 pelas bactrias do g‡nero Rhizobium, as quais promovem simbiose com as plantas. Estes micronutrientes foram estudados pelo fato de ambos poderem contribuir para o incremento da produtividade do feijoeiro. Devido a esse fato, para que se consiga aumentar a produtividade, em alguns casos,  necessŒria uma aduba„…o complementar. Apesar de existirem vŒrios mtodos de fertiliza„…o, devido a particularidades, eles nem sempre se mostram eficientes. Com isso, o objetivo do presente estudo foi avaliar os componentes de produ„…o, teor e acumula„…o de nutrientes nos gr…os do feijoeiro Cultivar IAC - Alvorada, em dois tipos de solo, sob diferentes formas de aplica„…o lŠquida desses micronutrientes (Zn e Mo). Os experimentos foram conduzidos em t‘nel plŒstico, no Departamento de Recursos Naturais/Ci‡ncia do Solo da FCA/UNESP Campus de Botucatu/SP. Os solos utilizados foram Latossolo Vermelho Escuro distrfico textura mdia (Led) e Latossolo Roxo distrfico textura argilosa (LR). Os vasos utilizados no experimento foram de 15 dm3 de terra seca ao ar passada em peneira de 4 mm. Os tratamentos foram compostos quanto † forma de aplica„…o sendo: pulverizado junto † semente, pulverizado junto ao adubo NPK na semeadura e pulverizado na superfície do solo. E quanto à adição de Zn e Mo foram: com Mo, com Zn e com Mo + Zn (juntos); foram também utilizadas três testemunhas: duas relativas, sendo a primeira... (resumo completo, clicar acesso eletrônico abaixo) / Abstract: The mineral nutrition of beans with macro and micronutrients is indispensable to survival, development and affects directly productivity. Micronutrients in turn are needed in small quantities, being difficult its correction, to the levels required by plants are supplied. Amongst theses micronutrients, Zn is a sparse nutrient in Brazilian soils, on the other hand Mo has a vital importance, because improve the utilization of N2 by bacteria of genus Rhizobium, which promote symbiosis with plants. Theses micronutrients were studied because both can affect to increase common beans productivity. Because of this, to improve productivity is almost always required an additional fertilizer. Although there are a lot of fertilization methods, for some particularities, they do not always demonstrate efficient. For that reason, the purpose of this study was to evaluate production components, content and nutrients accumulation in the grain of common beans cv "IAC - Alvorada", in two kinds of soil, into different methods of liquid application of theses micronutrients (Zn and Mo). The research was carried out in a greenhouse of Natural Resources Department/Soil Sciences, FCA/UNESP, Botucatu/SP, the used soils were Red Latosol medium texture and a Red Latosol clayey texture. The pots used on that research were 15dm3 of dry land to air passed through sieve of 4 mm. The treatments were consisted of application methods: sprayed on seeds, sprayed on fertilizer NPK at sowing and sprayed on the soil surface. And consisted of Zn and Mo addition were: with Mo, Zn and Mo + Zn (together); three more controls: two relatives controls with Zn mixed with NPK and leaf fertilization with Mo and one more called absolute control, without Zn and Mo addition. It consisted of twelve treatments with four replications; the experimental design was completely randomized blocks. It was concluded that methods of micronutrient... (Complete abstract click electronic access below) / Mestre
32

Metabolismo do nitrogênio e senescência em razão da aplicação de níquel no cafeeiro arábica / Nitrogen metabolism and senescence process in coffee plants exposed to nickel

Tiago Tezotto 18 May 2015 (has links)
O nitrogênio é o nutriente exigido em maior quantidade pelo cafeeiro e o segundo mais exportado pela planta. Usualmente se aplica ureia no cafeeiro e o N desta fonte é rapidamente metabolizado e incorporado na forma de aminoácidos e amidas. A assimilação do nitrogênio é afetada por diversos micronutrientes, entre eles o níquel (Ni), por ser este um constituinte da enzima urease, responsável pela degradação da ureia. O entendimento da interação do Ni com o metabolismo do N e o processo de senescência no cafeeiro é importante para o uso eficiente do nitrogênio pelas plantas. Pouco se sabe a respeito da nutrição com Ni no metabolismo do N, na senescência foliar e na interferência na absorção e transferência de outros nutrientes. A presente pesquisa foi realizada para avaliar se a aplicação de Ni (i) interferiria na absorção e transferência de outros nutrientes, bem como na partição de biomassa do cafeeiro e; (ii) aumentaria a eficiência de uso do N, tanto pela maior degradação da ureia, via atividade da urease, quanto pelo aumento da redistribuição de reservas de nitrogênio, por meio do incremento do catabolismo da arginina; e (iii) se o fornecimento de Ni atrasaria a senescência foliar, pela diminuição da produção de etileno endógeno na planta, o que aumentaria a duração foliar. A aplicação de Ni reduziu a biomassa do cafeeiro somente no maior teor do elemento disponível no solo (105 mg DM-3), e essa redução na biomassa afetou a concentração e acúmulo, principalmente, dos macronutrientes (N, P, K, Ca e Mg). Com relação aos micronutrientes metálicos (Cu, Fe, Mn e Zn), o incremento gradual no teor de Ni disponível, reduziu ou elevou gradualmente a concentração desses micronutrientes no cafeeiro. Os coeficientes de eficiência de uso de N pelo cafeeiro foram afetados somente em razão do nível de N, sem alteração em função do Ni disponível no solo. A aplicação de Ni no solo até teores de 60 mg dm-3 não afetou o crescimento da planta de cafeeiro, mas aumentou a retenção foliar no nível deficiente de N. O Ni reduziu a biossíntese de etileno na planta, apesar das concentrações de MDA e prolina aumentarem com o teor disponível de Ni no solo na pré-antese. Com relação ao N, houve incremento na redistribuição de N dos órgãos de reserva (ramo) para atender a demanda de folha e fruto. / Nitrogen is the nutrient required in greatest quantity by the coffee and the second most exported within the plant. Usually, N is applied as urea to coffee and urea-N is rapidly metabolized and incorporated into amino acids and amides. The assimilation of N is affected by several micronutrients, including nickel (Ni). Ni is a constituent of urease, the sole enzyme responsible for degradation (and subsequent assimilation) of urea. Understanding Ni interaction with N metabolism and the aging process is important for the efficient use of nitrogen by coffee, and by plants in general. Little is known about Ni nutrition as it relates to N metabolism in leaf senescence and its possible interference in the absorption and transfer of other nutrients. The present study was conducted in coffee to assess whether the application of Ni (i) interferes with the absorption and transfer of other nutrients as well as biomass partitioning; (Ii) increases the nitrogen use efficiency, both for greater degradation of urea via urease activity, and increased redistribution of nitrogen reserves by increased catabolism of arginine; and (iii) delays leaf senescence by decreasing endogenous ethylene production, thereby increasing leaf duration. Ni application reduced biomass of coffee only at the highest level of soil availability (105 mg dm-3). This level also brought about the reduction in biomass concentration and accumulation of macronutrients (N, P, K, Ca and mg). With respect to mineral micronutrients (Cu, Fe, Mn and Zn), gradual increases in available Ni content, either reduced or gradually increased the concentration of these micronutrients. N-use efficiency ratios in coffee were affected only by variations in management of N, and not by changes in available soil Ni . Soil Ni applications to 60 mg dm-3 did not affect the growth of the coffee plant, but increased foliar retention under N limitation. Ni reduced plant ethylene biosynthesis, in spite of the concentrations of MDA and proline increasing rising with increasing soil Ni during pre-anthesis. As Ni levels rose, there was an increase in the redistribution of N of storage organs (branch) to meet the demand of leaf and fruit.
33

Cálcio e boro para soja-perene: características anatômicas e agronômicas e concentração de nutrientes / Calcium and boron for perennial soybean: anatomical and agronomic characteristics and nutrient concentrations

Daniel Manfredini 31 March 2008 (has links)
Leguminosas forrageiras têm sido consorciadas com capins, e contribuído com a sustentabilidade do sistema solo-planta-animal. A soja-perene (Neonotonia wightii) é uma das leguminosas forrageiras bem adaptadas ao cultivo em áreas tropicais. A aplicação de cálcio e boro tem resultado em benefícios ao desenvolvimento da planta, especialmente para as espécies leguminosas. Este trabalho objetivou verificar os efeitos de combinações de cálcio e de boro para a soja-perene na morfofisiologia da planta, produção, concentração mineral, concentração de carboidratos na parede celular, em alterações anatômicas nos tecidos foliares e sintomas visuais. Foi conduzido um experimento em casa de vegetação com plantas de soja-perene cultivadas em solução nutritiva em vasos plásticos contendo quartzo moído como substrato. Empregou-se o delineamento de blocos ao acaso, e um esquema fatorial 52 incompleto, perfazendo um total de 13 combinações de doses de cálcio e boro. As plantas foram submetidas a dois períodos de crescimento. O primeiro corte das plantas foi realizado 46 dias após o transplante das mudas e o segundo 38 dias após o primeiro. O ponteiro (três folhas trifolioladas completamente expandidas contadas a partir do ápice) foi separado da porção inferior da planta (restante do tecido vegetal) e das raízes que também foram coletados. A interação cálcio x boro foi significativa apenas para a concentração de cálcio na porção inferior da soja-perene. As doses de cálcio alteraram a área foliar, as concentrações de cálcio, magnésio e potássio nos tecidos vegetais amostrados, e as concentrações de carboidratos na parede celular da planta. As doses de boro alteraram a produção, comprimento e superfície das raízes, as concentrações minerais nos tecidos analisados e as concentrações de carboidratos na parede celular das folhas. As combinações de baixas ou altas doses de cálcio e de boro promoveram alterações nas características anatômicas da soja-perene. Com o suprimento de boro de 10 mmol L-1 na solução nutritiva as plantas apresentaram deformações nas folhas novas e desenvolvimento anormal do sistema radicular. / Forage legumes have been mixed with grasses and contributed to improve the sustainability of the soil- plant- animal system. Perennnial soybean (Neonotonia wightii) is one forage legume well adapted to the tropical areas. Calcium and boron have resulted in benefits for plant development, particularly in legume species. This study was set with the objectives of verifying the effects of calcium and boron combinations for perennial soybean in plant morphophysiology, production, mineral concentrations, carbohydrate concentrations in cell wall, anatomical changes in leaf tissues and visual symptoms. A greenhouse experiment was carried out with plants grown in plastic pots containing ground quartz and supplied with nutrient solutions. An incomplete factorial 5 x 5, with 13 combinations of calcium and boron rates, was set in randomized block design. Plants were harvested twice, the first harvest one at 46 days after seedlings transplanting to the pots and the second harvest at 38 days after the first one. The upper part (three completely expended leaves) was separated from the lower part of plant tops and roots that were collected too. Calcium x boron interaction was only significant for the calcium concentration in the lower part of perennial soybean. Calcium rates changed leaf area, concentrations of calcium, magnesium and potassium in the sampled plant tissues, and carbohydrate concentrations in the cell wall of perennial soybean. Boron rates influenced changes in roots (dry matter, length and surface), mineral concentrations and carbohydrate concentrations in leaves cell wall. High or low rates of both calcium and boron had resulted in changes in anatomical characteristics of perennial soybean. When boron was supplied at 10 µmol L-1 plants presented deformed new leaves and abnormal root system growth.
34

Disponibilidade de boro para a cultura da soja em resposta a doses e fontes do nutriente e potenciais de água do solo / Availability of boron for the soybean crop in response to doses and the potentials sources of water nutrient soil

Trautmann, Ricardo Robson 28 August 2009 (has links)
Made available in DSpace on 2017-07-10T17:37:36Z (GMT). No. of bitstreams: 1 Ricardo_Trautmann.pdf: 645387 bytes, checksum: b943a284ef2f8a8c03b005a6d3050a51 (MD5) Previous issue date: 2009-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Soybeans are an annual crop demanding boron (B). However, the boron fertilizer management should be done cautiously, especially with regard to doses to be applied because of the narrow range between adequate and toxic for this nutrient in the soil. Another important aspect directly related to the availability of B to plants refers to soil moisture conditions, since B is preferentially transported into the soil to the surface of the roots by mass flow. In this context, this study aimed to evaluate the effect of sources and application rates of boron in the growth of soybean (Glycine max) in an Oxisol of medium texture, under different water tensions. The experiment was conducted in a greenhouse at Horticulture Station Protected Cultivation and the State University of West of Paraná, Marechal Cândido Rondon, PR, using pots with 5 dm3 of soil. We used a randomized split-plot in a factorial 5 x 2 x 3, with five doses of B (0.0, 0.25, 0.5, 1.0 and 2.0 mg dm-3); two sources (boric acid and colemanite) and three strains of soil water (-0.01, -0.03 and -0.10 MPa), with four replications. The results indicated that the development of soybean, in general, is not influenced when keeping the voltage level of water in the ground to -0.1 MPa (soil moisture of 65% of field capacity). The shoot growth of soybean was not influenced by boron fertilization, regardless of whether the withholding is more or less soluble. In turn, the root growth was negatively affected by the application of up to 2 mg dm-3 of B in soil with initial 0.4 mg dm-3. Under water tension of -0.1 MPa soil fertilization with B rates from 0.25 to 2.0 mg dm-3 as colemanite resulted in less loss of water by the soybean leaves. The amount of B in soil and soybean leaves increases linearly with increasing doses of the nutrient into the soil, was observed at the maximum dose, 2 mg dm-3 of B, typical symptoms of B toxicity in soybean leaves / A soja é uma das culturas anuais mais exigentes em boro (B). Entretanto, o manejo da adubação boratada deve ser realizado com muita cautela, principalmente no que diz respeito às doses a serem aplicadas, devido à estreita faixa entre o nível adequado e o tóxico para este nutriente no solo. Outro aspecto importante relacionado diretamente com a disponibilidade de B para as plantas refere-se às condições hídricas do solo, já que o B é preferencialmente transportado no solo até a superfície das raízes pelo fluxo de massa. Neste contexto, este trabalho objetivou avaliar o efeito da aplicação de fontes e doses de B no crescimento da soja (Glycine max) em um Latossolo Vermelho eutroférrico de textura média, submetido a diferentes tensões de água. O experimento foi conduzido em casa de vegetação, na Estação de Horticultura e Cultivo Protegido da Universidade Estadual do Oeste do Paraná, em Marechal Cândido Rondon, PR, em vasos com 5 dm3 de solo. Utilizou-se o delineamento experimental em parcelas subdivididas, em esquema fatorial 5 x 2 x 3, sendo cinco doses de B (0,0; 0,25; 0,5; 1,0 e 2,0 mg dm-3); duas fontes (ácido bórico e colemanita) e três tensões de água no solo (-0,01, -0,03 e -0,10 MPa), com quatro repetições. Os resultados obtidos indicaram que o desenvolvimento da cultura de soja, de maneira geral, não é influenciado quando se mantêm o nível de tensão de água no solo até -0,1 MPa (umidade do solo de 65% da capacidade de campo). O crescimento da parte aérea da soja não foi influenciado pela adubação boratada, independentemente se a fonte aplicada é mais ou menos solúvel. Por sua vez, o desenvolvimento do sistema radicular foi negativamente afetado com a aplicação de de até 2 mg dm-3 de B, em solo com teor inicial de 0,4 mg dm-3. Sob tensão de água no solo de -0,1 MPa a adubação com doses de B de 0,25 a 2,0 mg dm-3 como colemanita implicou em menor perda de água pelas folhas de soja. Os teores de B no solo e no tecido foliar da soja aumentam linearmente com o aumento das doses do nutriente aplicado no solo, sendo observado na dose máxima, 2 mg dm-3 de B, sintomas típicos de toxidez de B nas folhas de soja
35

The micronutrient profile of the typical American diet enhances colorectal carcinogenesis

Perez Monsanto, Stephany del Carmen 01 May 2013 (has links)
The typical Western dietary pattern is characterized by the consumption of energy-dense, nutrient-poor foods and has been linked to increased risk of colorectal cancer (CRC). Our research group previously developed the total Western diet (TWD) that emulates typical human dietary intakes of macro- (carbohydrates, proteins, and fats) and micronutrients (vitamins and minerals) on an energy density basis for rodents. In the present study, we sought to determine the impact of TWD on biomarkers of metabolic syndrome and obesity in comparison to a commercial 45% fat diet used for models of diet-induced obesity (DIO diet) and the standard basal AIN93G diet, which is optimized for rodent health. Also, we included 2 additional test diets to evaluate the contribution of the micronutrient (vitamin- and mineral-modified diet, [VMM]) or macronutrient (macro-modified diet [MM]) contents of the TWD in development of cancer, obesity, and glucose intolerance. A chemical carcinogenesis model of inflammation-associated colon cancer was employed to evaluate impact of diets on colon cancer in mice. As expected, mice consuming the DIO diet acquired an obesity/metabolic syndrome phenotype typified by increased food energy intake, greater rate of body weight gain, increased proportion of body composition as fat mass, higher fasting glucose, impaired glucose tolerance, and higher circulating levels of leptin. However, consumption of TWD did not alter any of these classic biomarkers of metabolic health, as these mice adjusted food intake so that energy consumption was similar to that for mice fed AIN93G. A different pattern was observed for colon carcinogenesis. Consumption of the TWD or VMM diet markedly increased colon tumor multiplicity and size compared to the AIN93G control, whereas consumption of the DIO or MM diets did not enhance colon tumorigenesis. Collectively, these observations point to a critical role of dietary micronutrients in colon carcinogenesis, and that this promoting effect is likely unrelated to the metabolic syndrome phenotype induced by a high fat diet. Moreover, our observations emphasize the need to take into account the micronutrient content of rodent basal diets when modeling typical U.S. nutrition in pre-clinical animal experiments in order to improve the translation of these studies to human nutrition and dietary intervention programs.
36

Screening of HvNAM-B1 gene polymorphism, grain nutrient content and seed size in 80 Scandinavian barley cultivars

Madhavan, Sharmila January 2011 (has links)
Micronutrient malnutrition is a leading worldwide health problem that affects billions of people particularly in the developing countries resulting in serious health conditions. The domestication of crops produced high yield and larger seed size but with a reduction in nutritious quality. The locus NAM or Gpc-1 affects both the seed size and nutrient content in wheat and barley. A non-functional allele of the gene increases the seed size but at the expense of protein and micronutrient content. However, this gene was found to be lost in wheat during the early domestication resulting in lower nutrient content. Therefore, the selection for high yield has lead to lower grain nutrients. Our aim of the present study is to investigate when the selection for yield occured in barley and to check the existence of the wild type allele in the 19th century of landrace barley crops. In addition, to analyse the barley grain concentration of protein, iron and zinc among the landrace and cultivars from various time periods of northern Europe. The grain nutrient concentration of Nitrogen, Iron and Zinc did not show significant difference among the investigated 80 Scandinavian barley accessions. The grain nutrient concentration did not correlate with the seed size and chlorophyll content. The polymorphism was not observed among the allelic diversity of HvNAM-1 gene indicating that the NAM-B1 gene still prevails in the 19th century barley cultivars.
37

NUTRITIONAL ASSESSMENT OF PRESCHOOL CHILDREN IN AN URBAN ECUADORIAN COMMUNITY

Bronner, Elizabeth A. 01 January 2015 (has links)
Objectives: The goal of this project was to determine the nutritional needs of preschool age children to help guide intervention development. The research aims were 1) to examine and describe young child (ages one to five) nutritional status as it relates to key nutrients associated with stunting and wasting; 2) to determine what key macro- and micro-nutrient deficiencies (primarily iron and zinc) are associated with wasting and stunting. Methodology: Study sample: Sixty-seven families with children ages one to five who participating in routine health care clinic visits during the UK Shoulder to Shoulder Global health brigade visits. Study design: A cross-sectional survey was conducted collecting demographic data, medical history, and dietary intake. Objective measures of height/length and weight were completed; and blood samples were drawn to measure serum micronutrient levels. Nutrition Data System for Research (NDSR) identified nutrient intakes for analytical comparison based on growth parameters. Nutritional and health status were compared to food security and World Health Organization growth reference points of standard deviations on Z-scores of height-for-age and weight-for-age. Analyses: Chi Square, ANOVA, and binary logistic regression tests were run using Statistical Analysis System (SAS) Results: Low serum levels of zinc and iron corresponded to low levels of dietary intake of zinc and iron, limited food security and moderate stunting z = -0 to 1.99 Standard Deviation. Conclusion: This study will inform a comprehensive nutritional intervention for this population. The evidence that specific nutrients are limiting will focus the health promotion objectives.
38

Controlling Iron Defeciency Anemia and Preventing Calcium Deficiency in Bangladesh Children: A Novel Approach Using a Multi-micronutrient Powder (MNP) Formulation

Khan, Waqas Ullah 25 August 2011 (has links)
Iron deficiency anemia (IDA) and calcium deficiency affect millions of children globally. Sprinkles is a multi-micronutrient powder (MNP) that has successfully treated anemic infants and can be modified to include additional micronutrients. The efficacy for treating IDA and preventing calcium deficiency requires evaluation due to potential nutrient interactions. We assessed the efficacy of Sprinkles MNP including iron with and without calcium on hemoglobin (Hb) response in 100 anemic rural Bangladeshi infants for 2 months. Sprinkles MNP with and without calcium resulted in a significantly higher Hb concentrations in both groups (P<0.0001 and P<0.0001). However, infants who received Sprinkles MNP without calcium had a significantly higher change in Hb concentration (P=0.024) and rate of recovery from anemia (P=0.008). No differences in socio-demographic or dietary characteristics were documented between groups. Although both groups had an improvement in Hb status, the antagonistic interaction between iron and calcium requires further study.
39

Controlling Iron Defeciency Anemia and Preventing Calcium Deficiency in Bangladesh Children: A Novel Approach Using a Multi-micronutrient Powder (MNP) Formulation

Khan, Waqas Ullah 25 August 2011 (has links)
Iron deficiency anemia (IDA) and calcium deficiency affect millions of children globally. Sprinkles is a multi-micronutrient powder (MNP) that has successfully treated anemic infants and can be modified to include additional micronutrients. The efficacy for treating IDA and preventing calcium deficiency requires evaluation due to potential nutrient interactions. We assessed the efficacy of Sprinkles MNP including iron with and without calcium on hemoglobin (Hb) response in 100 anemic rural Bangladeshi infants for 2 months. Sprinkles MNP with and without calcium resulted in a significantly higher Hb concentrations in both groups (P<0.0001 and P<0.0001). However, infants who received Sprinkles MNP without calcium had a significantly higher change in Hb concentration (P=0.024) and rate of recovery from anemia (P=0.008). No differences in socio-demographic or dietary characteristics were documented between groups. Although both groups had an improvement in Hb status, the antagonistic interaction between iron and calcium requires further study.
40

The feasibility of implementing a point-of-use micronutrient fortification among African pre-school children : a pilot study / Ogunlade, Adebayo Olakunle

Ogunlade, Adebayo Olakunle January 2009 (has links)
Background The high prevalence of micronutrient deficiencies among South African preschool children reinforces the need for an intensified micronutrient malnutrition control strategy targeting children at home or in school. The use of recently developed micronutrient powders also known as "in-home fortification" or "point-of-use fortification" can be an effective long-term, sustainable approach in improving early childhood nutrition and cognitive developmental potential. However, before embarking on large-scale, long-term, point-of-use fortification trials, it is imperative to conduct external pilot trials in which the feasibility of implementing full-scale studies can be effectively assessed. Objective The objective of this study was to assess the feasibility of implementing a point-of-use micronutrient fortification trial among African preschool children, which would aid in pilot-testing the study design, logistics and implementation process as well as reveal limitations which can be addressed before the implementation of full-scale trials. Methods Preschool children (n = 151), aged 36 -79 months with haemoglobin concentration (Hb)<= 12.5 g/dL, from eight schools in a low socio-economic community were randomly assigned to an intervention (n = 76) and a control (n = 75) groups, both receiving breakfast maize-meal porridge, either with added micronutrient or placebo powder for 52 school days. Several process evaluation indicators (fidelity, dose delivered, dose received, reach, recruitment and context) were used to assess trial feasibility. Selected indicators of early childhood development (Hb concentration, anthropometric indices and cognitive function) were used to evaluate the outcome of the intervention within the context of a pilot study. Results The process evaluation results indicate that the various implementation components were delivered with high fidelity. Capacity development and strengthening of the front-line staff cognitive assessors and study assistants) was executed as planned. The point-of-use fortificant was well accepted among the children and the mean percentage of days the point-of-use fortificant or placebo was consumed (~85%) did not differ between the groups. There were significant increases in Hb concentration (p < 0.05) from baseline to follow-up in both the intervention [mean change: 0.38 g/dL (95% CI: 0.14, 0.61 g/dL)] and control [mean change: 0.57 g/dL (95% CI: 0.35, 0.80 g/dL)] groups, however, mean change did not differ significantly between the groups (p = 0.250). The intervention did not improve any of the anthropometric indices measured in the intervention group compared to control. However, there was a medium likelihood for practical significance for the two global cognitive scores assessed, nonverbal index [intervention effects: 7.20 (95% C!: 2.60,11.81); P = 0.002, effect size: 0.55] and mental processing index [intervention effects: 2.73 (95% CI: 0.25,5.70); P = 0.072, effect size: 0.36] on the Kaufman Assessment Battery for Children, second edition. Conclusion The feasibility of implementing a point-of-use micronutrient fortification trial was demonstrated among African preschool children with potential benefits of improving their cognitive function. The most important lessons learned from this trial that could help improve similar future large-scale trials included the recruitment and training of the most eligible front-line staff as well as identifying that the use of a simple field-friendly finger prick method to measure Hb concentration may not be sufficiently sensitive to show differences in iron status after the intervention. / Thesis (M.Sc. (Nutrition))--North-West University, Potchefstroom Campus, 2010.

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