This thesis is concerned with identifying some of the factors which affect the flesh quality of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss). The flesh of any food animal is of utmost importance. Much work has been carried out on the flesh of land animals, but comparatively little is known about the factors which affect the quality of fish flesh. Salmonids have been farmed for a relatively short period of time, but great advances have been made in the techniques for their rearing. Now that the fish can be grown easily, more information is required on the factors which affect their fish quality in order to produce a consistent product. Fish fed a high oil diet have a significantly higher level of flesh lipid than fish of the same size fed a low oil diet (uncertainty p < 0.001). This has implications for the eating quality of the fish as many attributes of the eating quality of smoked salmon are significantly affected by the flesh lipid content. The flesh texture becomes softer and the flavours stronger, apart from salty flavour which decreases dramatically with increasing lipid (p < 0.001). The general effect of increasing lipid is to increase the perception of overall flavour and the overall liking of the product, as judged by the ten person trained taste panel. In contrast there are much fewer effects of the lipid content on cooked salmon and there are no effects on the overall flavour or overall liking (p > 0.05). The colour of the flesh is of great importance to the flesh quality of salmonids. Stress at slaughter is known to affect the muscle chemistry post-slaughter. This work shows that reducing stress at slaughter significantly increases the colour of the flesh, resulting in lower lightness (p < 0.05), an increased red hue (p < 0.05) and reduced opacity (p < 0.05) as measured using the CElab 1976 method. The change in colour is also shown by an increased Roche colour card score using the subjective colour card score (p < 0.05). Reduced stress at slaughter is also found to result in a longer time to the onset of rigor (p < 0.001) and a reduced susceptibility to gaping of the flesh (p < 0.01). Current commercial 'best practice' methods of slaughter were found to be highly stressful to the fish. The red colour of the flesh has been previously reported to reduce during storage, but this research found no changes in the level of the pigment astaxanthin during 12 days of storage of salmon fillets on ice. No effects of the level of astaxanthin or the antioxidant vitamins ascorbic acid and a-tocopherol at slaughter were found on the eating quality of the cooked flesh, either fresh or after 12 days storage on ice. However, many other attributes of the eating quality were significantly affected during the storage period, with increases in many flavours and textures associated with "off' fish. This translated into a significant reduction in the expression of overall liking by the trained taste panel (p < 0.001). The research for this thesis has shown areas where further research is required to investigate factors having effects on flesh quality. The most important of these new areas is the effect of stress level at slaughter on flesh quality. There is a strong possibility that stress at this point has wide ranging effects, the results of which may actually confound improvements introduced into in other areas of quality control unless they are eliminated from salmon farming practices.

Orientador: Julieta Teresa Aier de Oliveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-22T23:25:41Z (GMT). No. of bitstreams: 1 Ferreira_AryannaSangiovani_M.pdf: 844020 bytes, checksum: 7242b357574d18d59b48c100198d16d9 (MD5) Previous issue date: 2013 / Resumo: No contexto de valorização da agricultura familiar no Brasil foi criado, em 2007, o Programa de Melhoria da Qualidade Genética do Rebanho Bovino de Minas Gerais, o Pró-Genética, uma parceria entre instituições públicas e uma associação de criadores de gado, com o objetivo de criar um fluxo de comercialização entre produtores de genética bovina com qualidade comprovada e pecuaristas familiares, visando à melhoria da produtividade dos rebanhos de leite e de corte. Verificaram-se nesta pesquisa junto aos protagonistas do Programa os benefícios que ele tem trazido a seus participantes, bem como as deficiências que limitam a efetivação de alguns de seus objetivos. Analisaram-se os depoimentos destes atores (representantes das instituições gestoras e pecuaristas familiares beneficiários do Programa), coletados em entrevistas semiestruturadas por um roteiro de questões abertas e propôs-se um conjunto de indicadores chaves que possa ser utilizado como ferramenta avaliativa continuada para o Programa. Pôde-se verificar a necessidade de maior envolvimento dos pecuaristas familiares na gestão do Programa, a utilização de metodologias avaliativas pelos técnicos de extensão e a inclusão de avaliações genéticas para os rebanhos de base comercial com vistas a garantir a tão desejada transição genética que está presente no discurso das entidades. Por outro lado, apesar das deficiências observadas, o Pró-Genética vem evoluindo significativamente, as instituições gestoras estão comprometidas com a sua melhoria e, em particular, a associação de criadores mostrou disposição efetiva para quebrar paradigmas e superar a dicotomia que, historicamente, a afastou dos produtores familiares. Acredita-se que o Pró-Genética é um programa legítimo, de alta complexidade no seu planejamento e execução e que possui uma importância política e social que vem atraindo adeptos em todo o território brasileiro e o interesse de outros países / Abstract: In the context of family agriculture improvement in Brazil it was created in 2007, the bovine livestock genetic improvement program of Minas Gerais, the Pro-Genetics, a partnership between public institutions and an Association of breeders, with the goal of creating a stream of trade between bovine genetic producers with reliable quality and small livestock producers, aimed at improving the productivity of milk and meat cattle. This article proposes to check with the protagonists of the Program the benefits which have brought to its participants, as well as the shortcomings that restrict operationalization of its objectives. Evidence examined these protagonists (represented by managing and institutions also attended family beneficiaries of the Program), collected in interviews semi structured by a script of open issues. There are evidences of the need for greater involvement of the families also in the management of the Program more effective utilization of evaluations methodologies by extension technicians involved in the Program and also a genetic evaluation for the family farming herd in other to guarantee a real genetic transition in the basic commercial herds in Brazil. Furthermore, despite the flaws, the Pro-Genetics comes evolving significantly, managing institutions are committed to its improvement and, in particular the breeders showed effective provision of breaking paradigms and overcome the dichotomy that, historically, moved them away from the small producers. It is concluded, finally, the Pro-Genetics is a legitimate program, high complexity in its planning, and has a political and social importance that comes attracting fans across the whole Brazilian territory / Mestrado / Gestão de Sistemas na Agricultura e Desenvolvimento Rural / Mestra em Engenharia Agrícola

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Sustainable Built Environments Senior Capstone Project / As countries around the world continue to deplete natural resources and as the world’s population continues to grow, many industries, as well as people, have begun to suffer from the strain on dwindling natural resources. Agriculture and food distribution industries send goods from all around the world to stock grocery stores, restaurants, and other retail centers. The high costs of the distribution format causes people to be unable to afford food even though the amount of production is more than sufficient. “Enough food is produced worldwide to feed all the people in the world (Leathers and Foster, 2009). However, despite this alarming truth, nearly one billion people are suffering from chronic hunger today. There are a wide range of factors that contribute to this problem, however, the most significant is poor food distribution.” (Mission: Feeding the World, 2014) In an attempt to diminish these issues, organizations such as the FAO (Food and Agriculture Organization of the United Nations) have focused their research on various ways to grow within smaller regions and lower transportation distances to limit costs. They focus on these attempts largely to reach their Urban Food and Supply goals of providing efficiency in distribution to stabilize supplies of low-cost food to provide for everyone rather than only those who can afford it. (FAO, 2000) Additionally, work has been done to decrease waste at points along the supply chain. The challenge and goal, however, should not be to limit the scope of travel by a small fraction, but completely eradicate it. Focusing on agricultural techniques that occur within urban areas could allow the growth of most agricultural products within the confines of a city. Practicing locally grown agricultural techniques could diminish food distribution costs as the distance of travel would become within a quick drive or walk. The inhabitants of the city could purchase food out of their own neighborhoods at a much lower cost. Restaurants and grocery stores could limit their supplies so that very little went to waste. Additionally, farms would be close by, meaning there would be no issues getting food in enough time as well as allowing a greater awareness of the product’s growing conditions. Residents would immediately have a much greater understanding of their food supply chain and could participate in the growing of those products. Classical agricultural techniques do not work in this setting. In typical agriculture techniques, the growing population will outgrow the amount of land we have to grow crops. (Biello, 2009) Already today, over 80% of the land that is suitable for raising crops is in use (FAO and NASA). Historically, some 15% of that has been laid waste by poor management practices (Despommier, 2011). To simply account for the population growth predicted, food production will have to increase by 70% according to the UN’s Food and Agriculture Organization (2011). As the same percentage of people move towards urban living, the question is, should the food production industries follow suit? Unfortunately, space is both limited and at a premium in an urban environment. Vertical farming could be a solution to agriculture needs with population growth. Vertical farming allows skyscrapers to be filled with floor upon floor of orchards and fields, producing crops all year round (Technology Quarterly, 2010). The benefits of successful vertical farming are exceptional as it could reduce transport costs and carbon emissions, free up land, reduce spoilage, and finally, limit the water usage as compared to classic agriculture techniques. Unfortunately, there are limited examples of vertical farming and it remains mostly untested; however, some examples have begun to show up around the world. In the US, no vertical farms have been constructed, although the materials and technology exists. In the 2015 World’s Fair in Milan, this technology was showcased by Biber Architects in their project “Farm Walls”, a hydroponic technology that allows the plants to grow without soil and vertically (ZipGrow, 2017). Knowing the potential benefits of this type of system, the question remains of should agriculture transfer to this arrangement? What are the potential costs of these systems and technologies? Do the benefits outweigh the costs? Finally, what potential downfalls could result for farmers in non-urban environments? This capstone intends to analyze the costs and benefits of vertical farming technology as well as explore case studies of existing vertical farms to determine if it is an appropriate strategy for cities to adapt to address food insecurity.

Thesis (MScAgric)--Stellenbosch University, 2002. / ENGLISH ABSTRACT:ENGLISH ABSTRACT: Organic agriculture is a growing sector world wide due to the ecological and SOCIOeconomic crisis in conventional agriculture. The International Federation of Organic Agriculture Movements (!FOAM) estimated a growth rate of between 20 and 30 percent annually across the world. This trend is also detectable in South Africa although it is still a relatively new movement. During the last two years the number of farmers who had converted to organic farming has increased sixfold and although they still account only for a minute small percentage of the total agricultural production, the increasing importance of this sector can now be observed. This was the reason for this study, which dealt specifically with the conversion process to organic farming. Based on survey results, knowledge was gathered about organic farmers in South Africa concerning sociodemographic aspects, farming operations, motivations and problems of the conversion process. In the second part of the study, the focus was placed on three farming systems in the Western Cape, including pome fruit, vegetables and table grapes. Six farms were evaluated on the basis of technical, social and economic aspects of the conversion period. Several differences were observed between organic and conventional farmers, including a higher level of education and a younger age of organic farmers. Mainly horticultural holdings were converted, with a potential for exporting. Problems farmers had to face during the conversion period included the lack of knowledge and information, higher weed infestation and high certification and inspection costs. On most of the farms it was still too early to assess the financial impacts of the conversion, but where it was possible, the feedback was mainly positive. The changes that took place during the conversion period included technical changes such as the approach to pest and disease control, fertilization and seed inputs. Essential investments at the beginning of the conversion period were a financial burden. Variable costs rose mainly as a result of an increase in labour and machinery input. The conversion period had no obvious impact on the fixed costs and thus the net farm income. With respect to these findings it was recommended to support the conversion to organic farming not only financially with different instruments such as subsidies for certification costs but also to develop an improved infrastructure for marketing, networking and information exchange. Several areas for research were identified to increase the knowledge of organic farming in the South African context. / AFRIKAANSE OPSOMMING: Organiese boerdery is wêreldwyd 'n groeiende bedryf as gevolg van die ekologiese en sosioekonomiese krisis waarin konvensionele landbou verkeer. Die International Federation of Organic Agriculture Movements (lFOAM) het die groeikoers op tussen 20 en 30 persent per jaar wêreldwyd beraam. Hierdie neiging is ook in Suid-Afrika waar te neem, alhoewel dit hier nog' n relatief nuwe beweging is. Gedurende die afgelope twee jaar het die getal boere wat na organiese boerderyomgeskakel het, sesvoudig toegeneem. Alhoewel hulle nog 'n baie klein persentasie bydra tot die totale landbouproduksie, is die toenemende belangrikheid van die bedryf waarneembaar. Dit was die beweegrede vir hierdie studie, wat spesifiek klem gelê het op die omskakelingsproses na organiese boerdey. Beskrywende inligting oor organiese boere in Suid-Afrika, soos sosio-demografiese eienskappe, boerdery-aktiwiteite, motiverings en probleme met die omskakelingsproses, is met behulp van 'n opname verkry. In die tweede gedeelte van die ondersoek is daar op drie boerderystelsels in die Wes-Kaap gefokus, naamlik vrugte, groente en tafeldruiwe. Ses boerderye is aan die hand van tegniese, sosiale en ekonomiese aspekte van die omskakelingsperiode geëvalueer. Verskeie verskille is waargeneem tussen organiese en konvensionele boere, insluitend 'n hoër vlak van opvoeding en 'n jonger ouderdom van organiese boere. Hoofsaaklik boerderye in die hortologie, met uitvoer moontlikhede is omgeskakel. Van die probleme wat boere gedurende die omskakelingsperiode ondervind het, het 'n gebrek aan kennis en inligting, hoër voorkoms van onkruid, asook hoë sertifiserings- en inspeksiekoste ingesluit. By die meeste van die boerderye was dit nog te vroeg om die finansiële impak van omskakeling te kon beoordeel, maar waar dit tog moontlik was, is hoofsaaklik 'n positiewe terugvoer gevind. Die veranderinge wat gedurende die omskakelingsperiode plaasgevind het, het tegniese veranderinge soos die benadering tot pes- en siektebeheer, bemesting en saad ingesluit. Noodsaaklike investerings aan die begin van die omskakelingsperiode het 'n finansiële las tot gevolg gehad. Koste het hoofsaaklik weens 'n toename in arbeid- en masjinerie insette gestyg. Op grond van die bevindinge van die ondersoek is aanbeveel dat ondersteuning vir die omskakeling na organiese boerdery nie net finansieel deur middel van verskillende instrumente soos subsidies vir sertifiseringskoste gegee word nie, maar om ook 'n verbeterde infrastruktuur vir bemarking, netwerke en inligtingsuitruiling te ontwikkel. Verskeie gebiede vir verdere navorsing IS geïdentifiseer om kennis oor orgamese boerdery in die Suid- Afrikaanse konteks uit te brei.

Thesis (M.Sc. (Agriculture)) --University of Limpopo, 2009 / The purpose of the study was to assess nitrogen variability in tomato using the Remote Sensing Technique. The assessment was carried out through three growth stages (seedling, 50% flowering, and 50% fruiting stage). The GreenSeeker optical sensor unit that records NDVI values and total leafy nitrogen analyzer, “The Primacssn Nitrogen Analyzer,” was used in this study for data collection. Fertilizers were applied to the soil (Urea - 46% N, Superphosphate) every two weeks in the pots only for the treated experiment, and no nitrogen application for the untreated experiment. Tomato cultivars Flora Dade and Roma VF were used during the experimentation. The mean NDVI values for cultivars Flora Dade and Roma VF were 0.83 with N application. This value was 0.81 without N-application. The mean N-content for cultivars Flora Dade and Roma VF were 3.30 g/plant with N application. This value was 2.94 g/plant without N-application. The cultivar Flora Dade with N applied had higher N-content (3.38 g/plant) than the cultivar Roma VF with 3.22 g/plant when no N is applied across the three growth stages. The number of fruits’ means values at 50% fruiting stage for cultivars Flora Dade and Roma VF were 8.9 fruit per plant with N application. These mean values were 5 fruit per plant without N application. It was also evident that plants likely to have lower N content (untreated) had delayed maturation unlike those with nitrogen applied (treated), which had rapid/early maturation. Untreated plants took an average of 120 days till maturity, whereas the treated plants took an average of 100 days till maturity. Ground measurement of NDVI by the GreenSeeker sensor in this study showed potential for assessing nitrogen variability in tomato. / National Research Foundation

Thesis (M.Dev.) --University of Limpopo, 2011 / Agricultural development programs under the former apartheid homeland system which was dissolved in 1994 could not successfully achieve their objectives. The current democratic government reviewed the policies and programs put in place during apartheid era which eventually led to the implementation of the Revitalisation of Smallholder irrigation Schemes (RESIS) in line with the Reconstruction and Development Program (RDP) and Growth, Employment and Redistribution (GEAR) programs. It was anticipated that RESIS would among others improve agricultural productivity, play a role in local economic development, improve food security, provide improved benefits and the livelihoods of the rural communities where the schemes are situated. The aim of the study is to assess whether the RESIS program has had an impact so as to make recommendations for future similar programs. The objective of the study is to assess the impact of RESIS program on the livelihoods of the participants and to shed light on whether such programs can be used for poverty reduction, which is a key objective in the programs of LDA. Tšwelopele irrigation scheme in Greater Tubatse Municipality within Sekhukhune District Municipality was selected as the area at which the study was conducted. A random sample of 50 beneficiaries was selected from a total of 75 RESIS beneficiaries and divided into two strata, namely, full-time farmers (both male and female) and part-time farmers (male and female) farmers. Interviews were conducted through completion of questionnaires responded to by the selected participants and key informants in the scheme. Qualitative and quantitative methods were used to obtain the responses from the scheme participants and the data processed using SPSS. Based on the analysis of respondents‟ perceptions of the farmers, the study concludes that RESIS is perceived to have had a positive impact on the livelihoods of the beneficiaries. Gross margin analysis supports the farmers‟ perceptions.

Bibliography: leaves 220-247.

Bibliography: leaves 220-247. / x, 247 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Science, 2001