Dissertations / Theses on the topic 'Nutritional value'
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Chaudhry, Abdul Shakoor. "Nutritional improvements of cereal straws." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279301.
Full textClarke, Emily Jane. "Nutritional value of soya beans for broiler chicks." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366471.
Full textRehman, Salim-Ur. "Factors influencing quality and nutritional value in chapaties." Thesis, University of Strathclyde, 1994. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=23309.
Full textMatos, Bárbara Cartagena da Silva. "Do sea otters according to prey's nutritional value?" Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/17176.
Full textA Teoria do Forrageio Ótimo propõe que o estímulo nutricional na escolha de presas e busca de alimento em carnívoros é o ganho energético. Em contraste, pesquisas recentes sugerem que os carnívoros selecionam presas que fornecem uma dieta com um equilíbrio específico de macronutrientes (gordura, proteína, hidratos de carbono), ao invés do maior conteúdo energético. Para este efeito, as escolhas de presas de lontras-marinhas (Enhydra lutris) que habitam Sitka Sound no sudeste do Alasca, foram estudadas durante os meses de maio a agosto de 2016. Os objetivos desta pesquisa foram: 1) descrever a dieta das lontras-marinhas em Sitka Sound; 2) descrever o valor nutricional das suas presas; 3) comparar diferenças na escolha de presas de acordo com o sexo; e 4) avaliar e comparar o valor nutricional das presas com as escolhas das lontras-marinhas. Os dados de observação foram coletados oportunisticamente, através de uma plataforma de oportunidade. As presas de lontras-marinhas foram capturadas em áreas arbitrárias de Sitka Sound, e analisadas quanto à sua percentagem em lípidos (teor de gordura) e calorias (densidade de energia). O consumo de presas foi significativamente diferente: as amêijoas foram as presas mais consumidas (68,6%), seguidos pelos ouriços-do-mar (14,3%), vieiras (5,7%), pepinos-do-mar (5,7%), caranguejos (2,9%) e estrelas-do-mar (2,9%). Além disso, os resultados revelaram uma significativa diversidade no conteúdo de gordura e densidade energética entre presas de lontra-marinha. O abalone registou maior teor de densidade energética, seguido pelas vieiras, enquanto que os ouriços-do-mar registaram maior teor em lípidos. A escolha de presas e a ingestão de nutrientes não diferiram significativamente entre machos e fêmeas, no entanto, os machos de lontras-marinhas consumiram mais moluscos do que as fêmeas, enquanto que as fêmeas consumiram mais ouriços-do-mar do que os machos. O trabalho sobre nutrição em carnívoros é preliminar, e estes resultados fornecem um ponto de partida para futuras pesquisas. As respostas a estas questões não só terão implicações significativas na gestão das populações de predadores e das comunidades ecológicas de que fazem parte, mas também acrescentarão informações importantes sobre a biologia de predadores que até agora foram negligenciadas. Além disso, os conflitos nas comunidades sobre os impactos que as lontras-marinhas têm na pesca comercial no sudeste do Alasca, não podem ser ignorados. Compreender as escolhas de presas de lontras-marinhas pode fornecer previsões de como a pesca pode ser afetada, de acordo com o crescimento da população de lontras nesta área, a fim de ajudar políticos, membros da comunidade e pescadores comerciais, a responder em conformidade.
Foraging theory proposes that the nutritional driver of prey choice and foraging in carnivores is energy gain. In contrast, recent research suggests that carnivores select prey that provides a diet with a specific balance of macronutrients (fat, protein, carbohydrates), rather than the highest energy content. To this effect, the prey choices of sea otters (Enhydra lutris) inhabiting Sitka Sound, in southeast Alaska, were studied during the months of May-August of 2016. The goals of this research were to 1) describe sea otter’s diet in Sitka Sound; 2) describe the nutritional value of sea otters’ prey items; 3) compare differences in prey choice according to sex; and 4) evaluate and compare prey’s nutritional value with sea otter’s prey choices. Foraging observational data were collected opportunistically on a boat-based platform of opportunity. Sea otter’s main prey were captured in arbitrary areas of Sitka Sound, and analyzed for percentage in lipids (fat content), and calories (energy density). Prey consumption was significantly different: clams were the most frequently consumed prey (68,6%), followed by sea urchins (14,3%), scallops (5,7%), sea cucumbers (5,7%), crabs (2,9%) and sea stars (2,9%). Also, the results revealed a significant diversity in content of fat and energy density between sea otter prey specimens. Abalone ranked first on content of energy density, followed by scallops, while sea urchins recorded the highest lipid content. Prey choice and nutrient intake were not significant different between male and female sea otters, nevertheless, males consumed more clams than females, while females consumed more sea urchins than males. The work on carnivore nutrition is preliminary, and these results provide a starting point for future work. Answers to such questions not only will have significant implications for managing predator populations and the ecological communities of which they are a part, but will also add important information on predator biology that has been neglected so far. Moreover, communities’ conflicts over the impacts sea otters are having on commercial shellfisheries in southeast Alaska cannot be overlooked. Understanding sea otter’s prey choices may provide information and predictions of how fisheries may be affected as the sea otter population grows in this area, in order to help decision makers, policy makers, community members, and commercial fishermen respond accordingly.
Abdel-Muttalab, Salah Ahmed. "Nutritional value of rapeseed and faba bean for poultry." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.283076.
Full textD'Souza, Frances M. L. "The nutritional value of microalgae to penaeid prawn larvae." Thesis, Queensland University of Technology, 1997. https://eprints.qut.edu.au/36935/1/36935_Digitised%20Thesis.pdf.
Full textLewu, Muinat Nike. "Studies on the nutritional value of seven accessions of cocoyam growing in South Africa." Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/d1001054.
Full textQiao, Yanrui. "Routine techniques for monitoring the nutritional value of animal meals." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20011030-112347.
Full textFeed mills demand routine techniques to analyze digestible amino acids in highly variable animal meals. As routine tools, infrared spectroscopic predictions of digestible amino acids require reference samples assayed in vivo. Lack of reference samples resulting from costly and time-consuming in vivo assays has limited infrared spectroscopic applications. To remove this limitation, an in vitro assay mimicking in vivo digestion in swine was sought as a replacement to build the reference database.
Pepsin and pancreatic proteases used in the in vitro assays produce autolysates that are assayed as digestible amino acids. To correct this contamination and define incubation time for efficient use of the proteases, the autolysis of these proteases was studied. Correction of enzyme contamination with enzyme blank incubations and incubation time of 24 hours for pepsin and 96 hours for pancreatic proteases were proposed (Chapter III and IV).
In vitro digestion focused on maximal hydrolysis of peptide bonds with minimal enzyme usages for restriction of enzyme contamination. The minimal enzyme usage was determined to be 6.5% (enzyme to substrate ratio) (Chapter V).
Study on absorption of peptides in swine revealed that all soluble in vitro peptides could be estimated as digestible in vivo. Average in vitro digestibility coefficients were comparable to in vivo for a number of amino acids but mismatch occurred for individual samples. In vivo digestible amino acids, though, could be predicted with in vitro digestible amino acids. For example, lysine was predicted with an error of 0.27% (Chapter VI).
Total and digestible amino acids were predicted with near infrared reflectance spectroscopy (NIRS) and mid infrared Fourier transform infrared spectroscopy (FTIR) but not with Raman spectroscopy. Infrared spectroscopic prediction errors for digestible lysine were 0.27% for near infrared spectroscopy and 0.26% for mid infrared spectroscopy. Total amino acids seemed better predicted than digestible amino acids by infrared spectroscopy (Chapter VII).
The study showed that as routine techniques, infrared spectroscopy could potentially replace both in vivo and wet chemical analyses of amino acids.
Ряшко, Галина Михайлівна, and Вікторія Миколаївна Шелудько. "DESIGNING OF BAKING AREA SPECIALIZING ON HIGH NUTRITIONAL VALUE PRODUCTS." Thesis, Прага, 2021. http://dspace.puet.edu.ua/handle/123456789/10725.
Full textРяшко, Галина Михайлівна, and Вікторія Миколаївна Шелудько. "Designing of baking area specializing on high nutritional value products." Thesis, Oktan Print, 2021. http://dspace.puet.edu.ua/handle/123456789/11027.
Full textMundie, Benjamin Scott. "Nutritional Value of Warm- and Cool-Season Grasses for Ruminants." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/42804.
Full textMaster of Science
Issa, Salissou. "Nutritional value of sorghum for poultry feed in West Africa." Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/2322.
Full textAdebiyi, Adekunle Olalekan. "The nutritional value for poultry and pigs of biofuel co-products." Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5432/.
Full textChaudhry, Saeed Mukhtar. "Processing and nutritional value of poultry litter and slaughter house by-product." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-09162005-115004/.
Full textVinall, Sarah A. J. "A critical look at nutritional value of commercials on the Nickelodeon Network." Scholarly Commons, 2008. https://scholarlycommons.pacific.edu/uop_etds/689.
Full textForster, Lance Allen. "Nutritional value of flat pea hay fed to sheep at different levels." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43855.
Full textTwo experiments were conducted with sheep to determine the nutritional value of 'Lathco' flatpea (Lathyrus sylvestris) hay. In experiment 1, a finishing trial was conducted with 50 group fed crossbred lambs (25 ewes and 25 wethers) fed diets consisting of 70% chopped forage and 30% ground corn grain for 70 d. Five pens of five wethers and five pens of five ewes were selffed diets in which the forage consisted of 100:0, 75:25, 50:50, 25:75, and 0:100 proportions of alfalfa (Medicago sativa L.) and flatpea hay. Feed efficiencies decreased linearly (P<.05) as flatpea increased in the diet. Linear decreases (P<.05) were obtained in kidney and pelvic fat, backfat, leg conformation, and yield grade with increased flatpea in the diet. Blood urea-N (BUN), ruminal pH and NH3-N increased (P<.005) as proportion of flatpea increased. Total volatile fatty acid (VFA) and acetate concentration decreased linearly (P<.005) and propionate, isovalerate, and valerate levels increased linearly (P<.01) with increased proportions of flatpea hay. In experiment 2, 30 wether lambs were fed diets consisting of 100:0, 75:25, 50:50, 25:75 and 0:100 proportions of chopped alfalfa and flatpea hays in a digestion trial. Neutral detergent fiber (NOE), acid detergent fiber (ADE), cellulose, hemicellulose and energy digestibilities decreased linearly (P<.Ol) with increased levels of flatpea hay. Nitrogen retention was not different between sheep fed the different diets. Apparent absorbtion and retention of Ca decreased linearly (P<.05) with increased level of flatpea hay Ruminal pH and NHa-N, and BUN increased linearly (P<.OOl) as flatpea was increased in the diet. Ruminal total VEA, acetate and acetate to propionate ratio decreased linearly (P<.001) and propionate, isobutyrate, isovalerate, and valerate levels increased linearly (P<.001) as level of flatpea increased.
Master of Science
Wakeham, Andres I. "Preservation and nutritional value of caged layer waste treated with different preservatives." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/64568.
Full textMaster of Science
Jerónimo, Eliana Alexandra Sousa. "Dietary manipulation to inprove the nutritional value of lipids from lamb meat." Doctoral thesis, Universidade de Évora, 2011. http://hdl.handle.net/10174/15306.
Full textFellah, Abdulmunam Mohamed. "The nutritional value and toxic properties of buffalo gourd (Cucurbita foetidissima) plant." Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/185245.
Full textAl-Mamary, M. A. "Glucosinolate in rapeseed : toxic effects upon the liver and thyroid gland." Thesis, University of Newcastle Upon Tyne, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.255853.
Full textCapper, Brian Stephen. "Factors influencing the nutritive value of barley straw for ruminants." Thesis, University of Reading, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.238166.
Full textWidyaratne, Gemunu Prasanna. "Characterization and improvement of the nutritional value of ethanol by-products for swine." University of Saskatchewan, 2005. http://library2.usask.ca/theses/available/etd-12142005-151836/.
Full textIn study 1, two experiments were conducted to determine digestibility and digestible contents of energy, amino acids (AA) and P in corn and wheat DDGS and wheat grain, together with N and P excretion and growth performance in grower-finisher pigs. In experiment 1, 12 barrows (64.6 ± 6.4 kg) were fitted with ileal T-cannulae and had restricted access (2.6 x maintenance) to a wheat control diet or one of three diets with 40% corn, wheat+corn (4:1) or wheat DDGS. For energy, apparent total tract digestibility was highest for wheat (85%; P < 0.05) and did not differ among DDGS (77 to 79%; P > 0.10). Total tract digestible energy (DE) was highest for corn DDGS (4292 kcal kg-1 DM; P < 0.05) and tended to differ among wheat+corn and wheat DDGS and wheat (4038, 4019, and 3807, respectively; P = 0.06). For lysine, apparent ileal digestibility (AID) was highest for wheat (71%; P < 0.05) and did not differ among DDGS (59 to 63%; P > 0.10). The apparent ileal digestible lysine content was highest for corn DDGS (0.51% DM; P < 0.05), intermediate for wheat+corn and wheat DDGS (0.45 and 0.42), and lowest for wheat (0.37%). For P, total tract digestibility was lowest for wheat (15%; P < 0.05) and did not differ among DDGS samples (53 to 56%; P > 0.10). Total N excretion was highest for wheat+corn and wheat DDGS (55 and 58 g d-1; P < 0.05), intermediate for corn DDGS (44) and lowest for wheat (36). Total P excretion did not differ among DDGS (11 g d-1) and was lowest for wheat (8; P < 0.05). In experiment 2, 100 pigs (52.0 ± 3.3 kg) were fed a wheat-pea control diet or one of three 25%-DDGS (corn, wheat+corn or wheat) diets (3.375 Mcal DE kg-1; 2.50 g AID lysine Mcal-1 DE) for 5 wk. Overall, average daily feed intake (ADFI) and daily gain (ADG) were higher for wheat than DDGS (P < 0.05) but feed efficiency did not differ (P > 0.10). In summary, the nutritional value of wheat DDGS for swine is higher than wheat and lower than corn DDGS and feeding DDGS reduced growth performance, partly via a reduced ADFI, indicating that anti-nutritional factors in DDGS require further investigation.
In study 2, the effect of xylanase supplementation of wheat DDGS on nutrient digestibility and nutrient excretion was evaluated in grower-finisher pigs. Wheat-based diets with or without 40% wheat DDGS were tested with or without supplementary xylanase (4,000 U kg-1 feed) as a 2 x 2 factorial arrangement in a repeated Latin square design using eight barrows (29.4 ± 2.0 kg) fitted with ileal T-cannulae. Following a 6-day acclimation, faeces and urine were collected for 3 d, and ileal digesta for 2 d. The apparent ileal energy digestibility and DE content were not affected either by ingredient or xylanase (P > 0.05). The total tract energy digestibility and DE content were affected by ingredient (P > 0.05), but not by xylanase (P > 0.05). The total-tract energy digestibility was higher for wheat, but DE content was higher for wheat DDGS. The AID of arginine, isoleucine, leucine, phenylalanine, threonine, tryptophan and total AA were higher (P < 0.05), and of cysteine, histidine and lysine were similar (P > 0.05), and SID of phenylalanine was higher (P < 0.05), and of the other AA was similar (P > 0.10) for wheat DDGS compared to wheat. Supplementary xylanase improved AID and SID of most of the indispensable AA in wheat (P < 0.05), but not in wheat DDGS (P > 0.05). The apparent and standardized ileal AA contents were affected by ingredients (P < 0.05), but not by xylanase (P > 0.05). Digestible AA contents were higher for wheat DDGS than for wheat. The digestibility and digestible content of P were affected by ingredient and xylanse (P < 0.05). The P digestibility and digestible P contents were higher for wheat DDGS compared to wheat. Neither ingredient nor supplementary xylanase affected DM intake (P > 0.05). The DM excretion on daily basis and as a percentage of intake were affected by ingredient (P < 0.05), but not by xylanase (P > 0.05). Ingredients affected all N and P variables (P < 0.05), except percentage retained for both nutrients (P > 0.05). None of N variables (P > 0.05), but P intake and, retention on daily basis and as a percentage of intake were affected by xylanase (P < 0.05). The DM excretion and N and P intake, excretion and daily retention were higher for wheat DDGS compared to wheat. Lack of beneficial response to supplementary xylanase might be due to inappropriate enzyme level or insufficient substrate level of wheat DDGS. In addition, unidentified factors associated with fermentation and drying processes might constrain the nutritional value of wheat DDGS. Further studies are required to determine the proper xylanase inclusion level and/or to identify the factors associated with reduced nutrient digestibility of wheat DDGS.
Nanton, Dominic André. "Nutritional value of marine harpacticoid copepods as live food for marine fish larvae." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq24887.pdf.
Full textMasey, O'Neill Helen Victoria. "Influence of storage and temperature treatment on nutritional value of wheat for poultry." Thesis, University of Nottingham, 2008. http://eprints.nottingham.ac.uk/14130/.
Full textObamehinti, Johnson Muftau. "Effect of treating corn stover with aqueous ammonia and urea on nutritional value." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/45904.
Full textExperiments were conducted to study the effect of treatment of rectangular bales of corn stover with aqueous ammonia and urea solutions. The stacks were covered with polyethylene sheets for 129 d, after which they were uncovered, aerated and sampled for laboratory analyses.
Master of Science
Diamanti, Jacopo. "Quality, nutritional quality and nutraceutical value as a new task for strawberry breeding." Doctoral thesis, Università Politecnica delle Marche, 2011. http://hdl.handle.net/11566/241922.
Full textIn recent times increasing attention has been paid by consumers to the health and nutritional aspects (vitamins contents, mineral elements, antioxidants, etc.) of horticultural products. Fruits and vegetables contain antioxidant compounds, in addition to vitamin C or E and carotenoids, that significantly contribute to their total antioxidant capacity, such as phenolic acids (flavonoids, anthocyanins, tannins ellagitannins ecc.). Berry fruits are one of the richest sources of antioxidant phytochemicals encountered. Among berries strawberry fruit is one of the more attractive, due to its aspects and taste, but lately consumers have also focused their attention on strawberry fruit health-related compounds. For such reason researchers have focus their attention on strawberry fruit nutritional attributes, characterizing fruit bioactive compounds and understanding the physiological development of such compounds. Increasing awareness on multiple genetic and environmental factors affecting production and accumulation of bioactive compounds is observed among agronomic investigators, but these factors are rarely taken in account when fruit is marketed. The assumption underlying the ‘functional fruit’ is that the bioactive compounds in fruit are efficacious for the improvement of health. Rigorous and unprejudiced evaluation of the scientific evidence requires a defined set of criteria and methods of evaluation. The methods available for detecting fruit bioactive compounds can be suggested as fast and reliable tools for screening large breeding populations for high berry nutritional quality. The research carried on in these three years was focused on 1) the development of standardized methods for the evaluation of fruit bioactive compounds of European strawberry fruit germplasm collections, to identify genotypes able to provide new gene sources for increasing fruit nutritional value; 2) the evaluation of fruit nutritional quality of new strawberry genotypes generated by a breeding program based on the comparison of offspring populations originated by inter-specific backcross of F. virginiana spp.glauca and F. x ananassa intra-specific cross, with the aim to produce new genetic material with improved fruit nutritional quality; 3) validation of strawberry fruits antioxidant capacity against oxidative stress in vivo by a strawberry fruit supplementation in a sixteen week long term diet in rats. The results obtained by this multidisciplinary approach state the importance of developing methodologies of fruit nutritional evaluation fast and reliable, because of the main role that nutritional quality is acquiring. The nutritional evaluation of European strawberry collections confirm the importance of genotype in regards to bioactive compounds composition, but also the main role played by environmental conditions and location. Furthermore, the importance of wild genetic resources as new implement in strawberry breeding program aimed to improve fruit nutritional quality, is confirmed. Finally, the efficacy of strawberry antioxidant capacity against oxidative damage in vivo, is stated, even if the effect is strictly linked with the fruit bioactive composition and consequently strawberry genotype. This multidisciplinary approach will allow the release of new varieties able to offer better quality and consumer safety.
Shahnaseri, Mahnaz, of Western Sydney Hawkesbury University, of Science Technology and Environment Faculty, and School of Food Science. "The effect of cooking method upon iron and zinc bioavailability in rice." THESIS_FST_SFH_Shahnaseri_M.xml, 2001. http://handle.uws.edu.au:8081/1959.7/695.
Full textDoctor of Philosophy (PhD)
Koyama(Ito), Ayana. "Analysis of Nutritional Components of Spinach Under Root Chilling Stress." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/264639.
Full textBosch, Adina Cornelia. "Investigation of the chemical composition and nutritional value of smoothhound shark (Mustelus mustelus) meat." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20261.
Full textENGLISH ABSTRACT: The aim of this study was to determine the proximate composition of five individual body sites of the Mustelus mustelus shark in order to evaluate the cross carcass variation of the individual proximate components (moisture, protein, lipid, ash) of the meat. This variation was determined in order to find a representative sample of the edible part of the shark (fillet and body flap). Secondly, this sample representing the entire shark fillet was used to investigate the endogenous factors (gender, size and life cycle stage) and their effects on the individual proximate components and other meat components (amino acids, fatty acids, minerals, histamine and mercury contents). Finally, all this data was combined to describe the average chemical composition and nutritional value of M. mustelus meat. None of the proximate components showed any variation between the different fillet positions. This indicated that the fillet is homogenous and samples for chemical analyses can be taken anywhere on the fillet as representative of the entire fillet. It was found that all three main effects (gender, size and life cycle stage) did not have major influences on most of the components of the chemical composition of M. mustelus meat analysed. Higher fatty acid levels (SFA, MUFA and PUFA) were observed in large females than in large males as well as in non-pregnant large females compared to pregnant large females. According to statistical analysis, large males had higher total mercury levels than large females. The only component affected by size variation was the fatty acids, showing a trend to decrease in quantity before maturity was reached. Variation due to life cycle stages was mostly evident in the fatty acid component with some small effects on two mineral components, aluminium and copper, which had slightly higher levels in pregnant large females than in non-pregnant large females. M. mustelus meat has an average proximate composition of 75% moisture, 23% protein, 1.6% lipids and 1.4% ash (weight per wet weight). The protein is, however, an over-estimation of the true protein value as the meat contains significant amounts of non-protein nitrogen (NPN) in the form of urea which contributes to the N concentration. M. mustelus meat is a good source of some essential amino acids, especially lysine and threonine (78% of the daily requirements for an adult in a 100g portion), but low in minerals. The meat has a healthy lipid content with a good ratio (>0.45) of PUFA:SFA (0.83) as well as a healthy (<4) n-6:n-3 fatty acid ratio of 0.39. The histamine content was very low or not detectable but some samples contained total mercury values above the maximum safe limit. Although further research is needed for some meat components, these results are a valuable contribution to the new South African Food Composition Tables being compiled.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die proksimale samestelling van die vleis vanaf vyf afsonderlike posisies op die liggaam van die Mustelus mustelus haai te bepaal. Sodoende is die variasie, met betrekking tot die verskillende proksimale komponente (vog, proteïen, lipiede en as), in terme van die totale karkas, bepaal. Die proksimale variasie is bepaal om vas te stel hoe ʼn verteenwoordigende monster van die totale karkas geneem kan word. Gevolglik is hierdie verteenwoordigende monster gebruik om die effek van geslag, grootte en die verskillende fases van die lewens-siklus op die afsonderlike proksimale komponente asook ander vleis komponente (aminosure, vetsure, minerale, histamien en kwik inhoud) te ondersoek. Laastens is al hierdie inligting gebruik om die algemene samestelling en voedingswaarde van M. mustelus vleis te bespreek. Geen van die proksimale komponente het enige variasie getoon tussen afsonderlike liggaamsposisies nie. Hierdie resultaat dui daarop dat die vleis van ʼn M. mustelus haai homogeen is regoor die karkas en dat ʼn vleis monster vanaf enige posisie op die karkas geneem kan word as ʼn verteenwoordigende monster. Daar is gevind dat geslag, grootte en fase van die lewens-siklus geen merkwaardige invloed het op die vleis se samestelling nie. Hoër vetsuur konsentrasies (versadigde, monoonversadigde en poli-onversadigde vetsure) is gevind in groot vroulike haaie en nie-dragtige vroulike haaie as in groot manlike haaie en dragtige vroulike haaie onderskeidelik. Statisties, het groot manlike haaie hoër vlakke van totale kwik as groot vroulike haaie. Die enigste vleis komponent wat beïnvloed is deur die grootte van die haai, is die vetsure, wat verminder het voor volwassenheid bereik is en dan weer vermeerder soos die haai groter word. Variasie as gevolg van die verskillende fases van die lewens-siklus is meestal gevind in die vetsuursamestelling, en die minimale het ook gevarieer ten opsigte van die elemente aluminium en boor wat effense hoër vlakke getoon het in dragtige haaie as in nie-dragtige haaie. M. mustelus vleis het ʼn gemiddelde proksimale samestelling van 75% vog, 23% proteïen, 1.6% lipiede en 1.4% as (nat massa). Die proteïen waarde is ʼn oorskatting van die ware proteïen waarde as gevolg van hoë nie-proteïen stikstof in die vorm van ureum wat bydra tot die totale stikstof inhoud. M. mustelus vleis blyk ʼn goeie bron van sommige essensiële aminosure soos lisien en treonien (78% van die daaglikse aanbevole dosis), maar laag in mineraal inhoud. Die vleis het ʼn gesonde vet inhoud met ʼn goeie (>0.045) poli-onversadigde:versadigde vetsuur verhouding (0.83) asook ʼn gesonde (<4) omega 6 tot omega 3 vetsuur verhouding van 0.39. Die histamien inhoud van die vleis was baie laag of onder die meetbare limiet, maar sekere monsters het ʼn totale kwik inhoud getoon wat bo die maksimum veilige limiet is. Hoewel verdere navorsing ten opsigte van sekere van die vleis komponente vereis word, lewer hierdie resultate ʼn waardevolle bydrae tot die nuwe Suid-Afrikaanse voedsel samestellings tabelle wat tans opgestel word.
Mahmood, Sultan. "Chemical treatment of salseed meal : effects on nutritional value and physiological effects in the fowl." Thesis, University of Newcastle Upon Tyne, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239024.
Full textMoulay, Leila. "Physiological studies in rats of the nutritional value of a cocoa powder derived bulking agent." Thesis, University of Salford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.357121.
Full textMonteiro, Ana Cristina Saragoça Melgado Gonçalves. "Relationship between Portuguese consumer preferences and textural properties, chemical composition and nutritional value of beef." Doctoral thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2012. http://hdl.handle.net/10400.5/4857.
Full textBeef is a nutritionally rich product with a high economic value. However in the last decades beef has been target of negative publicity by the media, mainly due to the high content of cholesterol as well as saturated and trans fatty acids (FA). The increasing number of food scares across the Europe over the last years has increased even more consumers’ concerns about beef quality and safety. Despite the health concerns beef sensory properties still remain the main purchasing and repeat purchasing criteria for the consumers. Tenderness has been considered the major palatability characteristic of beef and defines its commercial value. However, tenderness variability has been considered a major problem to the beef industry. In this context, the aim of this proposal was to ascertain the organoleptic properties and lipid nutritional value of beef and to relate them with the Portuguese consumer` preferences. The experimental work was divided in two trials. In the first trial, the meat quality and lipid nutritional value from “Vitela Tradicional do Montado”-PGI veal, Mertolenga-PDO veal and Mertolenga-PDO beef were studied. The results suggested that the three products are not very different, but the two veal types are more alike, which means that age had a more powerful effect than the crossbred or gender. Nevertheless, despite the similarity in FA profile and of the production systems of the animals sampled, it was possible to discriminate the meat types. Moreover, the PGI veal seems to have higher variability than the other two meat types studied. In the second trial, three beef types from the Portuguese market place, Carnalentejana-PDO, imported from Brazil and national undifferentiated beef, were studied and compared to characterise nutritional value and variability of beef lipids as well as the organoleptic properties and their variability. We also intended to relate the sensory attributes with instrumental measurements in order to realise if it is possible to predict sensory evaluation through instrumental measurements. Brazilian beef had the highest lipid nutritional value and lipid stability as this beef presented higher contents of α-tocopherol, β-carotene, CLA and PUFA. The data indicated that all beef types seem to have α-tocopherol values high enough to inhibit lipid oxidation and discoloration. Energy intake was calculated for the main FA and compared with the recommended daily intake. All beef types seem to have low cholesterol and SFA contents. Concerning the relation between the sensory attributes and the instrumental measurement, sensory tenderness was correlated with WBSF but not with TPA hardness. Nevertheless, TPA chewiness was well correlated with sensory tenderness indicating TPA usefulness to give addicional information of beef texture. Off-flavour was the ix main determinant of overall acceptability and Brazilian beef presented the highest and lowest values, respectively. Brazilian beef also had the lowest juiciness score, indicating that this beef type despite having the best lipid nutritional value can be rejected due to it sensory attributes. All beef types were considered slightly to moderately tender regarding WBSF and sensory tenderness mean values. National undifferentiated beef seem to have higher variability in the colour measurements, whilst Carnalentejana-PDO seems to depicted higher tenderness variability. Despite having mean values in the aforementioned attributes that indicates a consumer high acceptability, the high variability in both cases can be detrimental in the moment of sale.
RESUMO - Relação entre as preferências do consumidor português e a textura, composição química e valor nutricional da carne de bovino - A carne bovina é um produto nutricionalmente rico e de elevado valor económico. No entanto, nos últimos anos tem sido alvo de publicidade negativa por parte da comunicação social devido ao seu conteúdo em colesterol e em ácidos gordos saturados e trans. O crescente número de surtos alimentares na Europa aumentou a preocupação dos consumidores quanto à segurança e qualidade alimentar. No entanto, apesar das referidas preocupações, os atributos sensoriais ainda permanecem a principal razão que leva os consumidores a comprar e a repetir a compra de carne de bovino. A tenrura tem sido considerada o atributo mais importante da carne bovina e define o seu valor comercial, mas a sua variabilidade tem representado um problema para a indústria. Neste contexto, o objectivo deste trabalho foi determinar as propriedades organolépticas e o valor nutricional da fracção lipídica da carne bovina e relacioná-las com as preferências dos consumidores. O trabalho experimental consistiu em dois ensaios. No primeiro ensaio foram estudados a qualidade organoléptica e o valor nutricional da fracção lipídica da carne de vitela “Vitela Tradicional do Montado”-IGP e Mertolenga-DOP e do novilho Mertolenga-DOP. Os resultados sugerem que as duas vitelas têm composições similares, o que pode significar que o efeito da idade foi maior do que o efeito da raça ou género. Apesar das semelhanças do sistema de produção e no perfil lipídico as três carnes foram bem discriminadas. No segundo ensaio foram estudados a qualidade organoléptica e o valor nutricional dos lípidos das carnes de bovino Carnalentejana-DOP, importada do Brasil e nacional indiferenciada. Também aqui se pretendeu prever a qualidade sensorial das carnes com base nas medições instrumentais. Todos os tipos de carne apresentaram baixo teor em colesterol, e teor em α-tocoferol suficiente para inibir a oxidação lipídica e a descoloração. A carne Brasileira apresentou o melhor valor nutricional do perfil lipídico e potencial anti-oxidante, visto ter apresentado conteúdos superiores em α-tocoferol, β-caroteno, CLA e ácidos gordos poliinsaturados. A ingestão de energia foi calculada para os ácidos gordos mais importantes e comparada com as recomendações de ingestão diárias. Todos os tipos de carne apresentaram baixo conteúdo em colesterol e ácidos gordos saturados. Os atributos sensoriais apresentaram correlações baixas com os parâmetros instrumentais, e apenas a força de corte se correlacionou com a tenrura sensorial. No entanto, a tenrura sensorial correlacionou-se com a mastigabilidade indicando que o TPA pode ser útil, dando informação adicional sobre a textura da carne. O off-flavour foi o principal determinante da xi aceitabilidade da carne, apresentando a carne Brasileira os valores mais e menos elevados, respectivamente. A carne Brasileira foi também a menos suculenta, indicando que apesar de apresentar o melhor valor lipídico pode, no entanto, ser rejeitada pelas suas características sensoriais. Todas as carnes foram consideradas ligeira a moderadamente tenras, tendo em conta os seus valores de força de corte e de tenrura sensorial avaliada pelo painel de provadores. As carnes nacionais apresentaram heterogeneidade da sua composição química, a Carnalentejana-DOP na tenrura e a nacional indiferenciada na cor, o que é indesejável e pode condicionar a sua comercialização, pelo que este aspecto deve ser melhorado.
Sherfy, Mark Huffman. "Nutritional Value and Management of Waterfowl and Shorebird Foods in Atlantic Coastal Moist-Soil Impoundments." Diss., Virginia Tech, 1998. http://hdl.handle.net/10919/26575.
Full textPh. D.
Magar, Shirish M. "Fermentation characteristics and nutritional value of ensiled deep pit caged layer waste and corn forage." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/80059.
Full textMaster of Science
Udomkun, Patchimaporn [Verfasser]. "Increasing nutritional value of papaya (Carica papaya L.) by optimizing pretreatment and drying parameters / Patchimaporn Udomkun." Aachen : Shaker, 2015. http://d-nb.info/1075437016/34.
Full textRibeiro, J. E. M. M. (Jeronimo Ernesto Meneses Machado). "Growth, development and nutritional value of Amaranthus tricolor L. as affected by salinity and harvesting procedure." Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/53746.
Full textENGLISH ABSTRACT: Low crop productivity in arid and semi-arid regions is a problem caused by water stress as well as associated high levels of soil and water salinity. An increased demand for salt tolerant crops is experienced in these regions. Amaranth is a glycophyte and C4 dicotyledonous crop, well adapted to arid and semi-arid regions. Previous studies on the physiological response of salt-stressed amaranths have indicated that this crop is salt tolerant. As vegetable, amaranths can be harvested by uprooting and by topping. The most common harvesting method is by topping, allowing repeated harvesting. When harvested by topping, the cutting height is an important parameter that may be manipulated to optimise growth rates. In this study, plants were exposed to different salt stress levels and harvesting procedures while yield and quality of Amaranthus tricolor were investigated. Nutrient solutions at four different electrical conducti vi ty (EC) levels were used to fertigate the plants. At high EC levels (4 mS cm-l and 8 mS cm-lj, the length and diameter of main stems, internode lengths, stem weights as well as root weights were reduced, especially with a longer growth period. However, the shoot: root ratio and leaf protein yields increased and flowering was delayed. The best leaf yield was obtained where plants were fertigated at an EC of 4 mS cm-l for 45 days. The cutting height did not affect leaf yield, growth rates and leaf protein yield in plants fertigated at EC levels of 1, 2 and 4 mS cm-l. At an EC of 8 mS cm-l, the growth rate recovered to a value similar to that of plants fertigated with an EC of 2 mS cmonly where plants were topped at 25%. With this less destructive cutting height (topped at 25%), leaf yields, growth rates and ·leaf calcium and protein yields at an EC of 8 mS cm" were superior to that of plants topped at 50%. In plants topped at 25%, the recovered growth rates at EC 8 mS cm-l was probably due to more photosynthetic active tissue left after cuttings, resulting in the accumulation of compatible solutes for osmotic adjustment.
AFRIKAANSE OPSOMMING: Die invloed van soutstremmings en oesprosedures op die groei, ontwikkeling en blaarkwaliteit van Amaranthus trico~or L. Lae produksie van gewasse in ariede en semi-ariede gebiede is 'n probleem wat veroorsaak word deur watertekorte asook geassosieerde hoë peile van grondverbrakking en soute in water. 'n Verhoogde vraag na soutverdraagsame gewasse word in hierdie gebiede ervaar. Amaranthus is 'n glikofiet en dikotiele C4 gewas wat goed in ariede en semi-ariede streke aangepas is. Vorige ondersoeke oor die fisiologiese reaksie van Amaranthus op soutstremmings het daarop gedui dat die gewas soutverdraagsaam is. As groentegewas word dit ge-oes deur dit uit te trek of deur dit gereeld te top. Waar dit getop word is die oes-tophoogte 'n belangrike parameter wat gemanipuleer kan word om die groeitempo te optimaliseer. In hierdie ondersoek is plante aan verskillende peile van soutstremmings en oesprosedures blootgestel terwyl die opbrengs en kwaliteit van Amaranthus tricolor ondersoek is. Voedingsoplossings is teen vier elektriese geleidingspeile (EC) gebruik om plante te voedsproei. Teen hoë EC peile (4 mS cm-l en 8 mS cm-l ), het lengtes en die deursnit van hoofstamme, internode lengtes, stam massas en wortelmassas afgeneem, veral met lang groeiperiodes. Die opbrengs het egter bogroei:wortel verhouding en toegeneem terwyl blomvorming blaarproteien vertraag is. Die beste blaar opbrengs is na 45 dae verkry waar plante teen 'n EC van 4 mS cm-l gevoedsproei is. Oes-tophoogte het nie blaar opbrengs, groeitempo of blaar protei en opbrengs beïnvloed met EC waardes in voedingsoplossings van 1, 2 en 4 mS cm-l nie. Met' n EC van 8 mS cm-l het die groeitempo herstel tot 'n vlak, gelykwaardig aan wat by 'n EC van 2 mS cm-l verkry is, slegs waar teen 25% tophoogtes ge-oes is. Met hierdie minder destruktiewe oesmetode (oes-tophoogte 25%), was blaar opbrengs, groei tempo en blaar kalsium en -proteien opbrengste by 'n EC van 8 mS cm-l betekenisvol beter as waar die oes-topdiepte 50% was. Plante wat met 25% topdieptes ge-oes is se herstel in groetempo teen EC 8 mS cm-1 was waarskynlik te danke aan meer fotosinteties aktiewe materiaal wat na oes op plante gelaat is. Dit kon tot die akkumulasie van oplosbare stowwe en osmotiese aanpassings aanleiding gegee het.
Alfaia, Cristina Maria Riscado Pereira Mateus. "Contribution to the study of lipid composition and nutritional value of intramuscular fat in ruminant meats." Doctoral thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2009. http://hdl.handle.net/10400.5/1157.
Full textContribuição para o estudo da composição lipídica e do valor nutricional da gordura intramuscular na carne de ruminantes - A composição em ácidos gordos e o ácido linoleico conjugado (CLA) são temas actuais de grande interesse, com particular relevância para a qualidade da carne e saúde humana. As carnes de ruminantes têm sido consideradas alimentos pouco saudáveis, principalmente devido à sua fracção lipídica com elevada concentração em ácidos gordos saturados. Contudo, as gorduras edíveis dos ruminantes são a principal fonte natural de isómeros CLA, sendo os isómeros bioactivos (c9,t11 e t10,c12) associados a propriedades potencialmente benéficas para a saúde humana. Em Portugal, a informação científica disponível para apoiar a qualidade e a reputação da carne bovina de raças autóctones criadas segundo as especificações de Denominação de Origem Protegida (DOP) continua restrita. Para além disso, os dados disponíveis não permitem ter uma percepção global de como distintos factores influenciam a composição da carne, desde a sua produção até ao consumo. Neste contexto, a nossa investigação foi desenvolvida estudando o efeito dos regimes alimentares dos animais (pastagem×concentrado), processamento tecnológico da carne após o abate (irradiação) e tratamentos térmicos (fervura, microondas e grelhagem), no perfil lipídico, especialmente nos isómeros do CLA, e no valor nutricional de carne de ruminantes. Foram seleccionadas e caracterizadas 4 carnes tradicionais DOP (Carnalentejana, Mertolenga, Barrosã e Arouquesa). Os resultados sugerem que a gordura intramuscular das carnes de novilho relativamente às de vitela, apresentam menor valor nutricional ao longo do ano, devido ao sistema de produção semi-extensivo utilizado nos novilhos. Por sua vez, a Carnalentejana-DOP apresenta uma qualidade nutricional superior comparativamente à carne de vaca de produção intensiva. No sentido de avaliar em detalhe o efeito de diferentes regimes alimentares no valor nutricional dos lípidos da carne, bem como a sua utilidade como discriminantes químicos da origem da carne, realizou-se um ensaio controlado. Os dados obtidos reforçam os resultados anteriores que sugeriam que a carne de animais de pastoreio apresenta melhor qualidade nutricional (teores mais elevados de n-3 PUFA e CLA) do que a carne de animais alimentados a concentrado. Este facto traduz os efeitos benéficos da pastagem no perfil de ácidos gordos da carne. Relativamente às alterações na composição da gordura intramuscular, resultantes do efeito de processamentos seguintes ao abate, a irradiação, uma tecnologia prospectiva para a conservação das carnes, não promoveu modificações significativas. Os tratamentos térmicos, frequentemente utilizados em culinária, induziram um impacto moderado no perfil dos ácidos gordos, como consequência das perdas de humidade e concentração da gordura. Em resumo, a composição lipídica da gordura intramuscular das carnes de bovino DOP estudadas apresenta um valor nutricional acrescentado para os consumidores, considerando os valores de n-3 PUFA, CLA (total e do isómero c9,t11) e da razão n-6/n-3, contribuindo para a sua diferenciação no mercado.
RESUMO - Contribuição para o estudo da composição lipídica e do valor nutricional da gordura intramuscular na carne de ruminantes - A composição em ácidos gordos e o ácido linoleico conjugado (CLA) são temas actuais de grande interesse, com particular relevância para a qualidade da carne e saúde humana. As carnes de ruminantes têm sido consideradas alimentos pouco saudáveis, principalmente devido à sua fracção lipídica com elevada concentração em ácidos gordos saturados. Contudo, as gorduras edíveis dos ruminantes são a principal fonte natural de isómeros CLA, sendo os isómeros bioactivos (c9,t11 e t10,c12) associados a propriedades potencialmente benéficas para a saúde humana. Em Portugal, a informação científica disponível para apoiar a qualidade e a reputação da carne bovina de raças autóctones criadas segundo as especificações de Denominação de Origem Protegida (DOP) continua restrita. Para além disso, os dados disponíveis não permitem ter uma percepção global de como distintos factores influenciam a composição da carne, desde a sua produção até ao consumo. Neste contexto, a nossa investigação foi desenvolvida estudando o efeito dos regimes alimentares dos animais (pastagem×concentrado), processamento tecnológico da carne após o abate (irradiação) e tratamentos térmicos (fervura, microondas e grelhagem), no perfil lipídico, especialmente nos isómeros do CLA, e no valor nutricional de carne de ruminantes. Foram seleccionadas e caracterizadas 4 carnes tradicionais DOP (Carnalentejana, Mertolenga, Barrosã e Arouquesa). Os resultados sugerem que a gordura intramuscular das carnes de novilho relativamente às de vitela, apresentam menor valor nutricional ao longo do ano, devido ao sistema de produção semi-extensivo utilizado nos novilhos. Por sua vez, a Carnalentejana-DOP apresenta uma qualidade nutricional superior comparativamente à carne de vaca de produção intensiva. No sentido de avaliar em detalhe o efeito de diferentes regimes alimentares no valor nutricional dos lípidos da carne, bem como a sua utilidade como discriminantes químicos da origem da carne, realizou-se um ensaio controlado. Os dados obtidos reforçam os resultados anteriores que sugeriam que a carne de animais de pastoreio apresenta melhor qualidade nutricional (teores mais elevados de n-3 PUFA e CLA) do que a carne de animais alimentados a concentrado. Este facto traduz os efeitos benéficos da pastagem no perfil de ácidos gordos da carne. Relativamente às alterações na composição da gordura intramuscular, resultantes do efeito de processamentos seguintes ao abate, a irradiação, uma tecnologia prospectiva para a conservação das carnes, não promoveu modificações significativas. Os tratamentos térmicos, frequentemente utilizados em culinária, induziram um impacto moderado no perfil dos ácidos gordos, como consequência das perdas de humidade e concentração da gordura. Em resumo, a composição lipídica da gordura intramuscular das carnes de bovino DOP estudadas apresenta um valor nutricional acrescentado para os consumidores, considerando os valores de n-3 PUFA, CLA (total e do isómero c9,t11) e da razão n-6/n-3, contribuindo para a sua diferenciação no mercado.
This work was co-financed by Centro de Investigação Interdisciplinar em Sanidade Animal (Project CIISA/52.Carne-Bioactivos) da Faculdade de Medicina Veterinária da Universidade Técnica de Lisboa and Fundação para a Ciência e a Tecnologia (POCTI/CVT/2002/44750) and Ministério da Agricultura (AGRO/2003/512).
Rojo, Poveda Olga. "Valorisation of Compounds with High Nutritional Value from Cocoa By-Products as Food Ingredients and Additives." Doctoral thesis, Universite Libre de Bruxelles, 2021. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/322988.
Full textDoctorat en Sciences biomédicales et pharmaceutiques (Pharmacie)
info:eu-repo/semantics/nonPublished
Lane, Hillary Anne. "Variation in the nutritional value of Atlantic herring (Clupea harengus) from the Bay of Fundy, Canada." View electronic thesis (PDF), 2009. http://dl.uncw.edu/etd/2009-1/laneh/hillarylane.pdf.
Full textAlhadhrami, Ghaleb Ali. "Effect of preservatives and maturity on the nutritional value of alfalfa hay for lactating dairy cows." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185343.
Full textŠottníková-Zajacová, Ivana. "Dietary strategies to improve the nutritional value of pork while maintaining a high sensory and technological quality /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17819.
Full textZingbagba, Mark. "Three essays on Upstream and Downstream Disruptions along Nutritional High-value Food Supply Chains in Emerging Countries." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSES029/document.
Full textThis dissertation presents three essays on disruptions along nutritional high-value food supply chains in emerging countries. It extends our understanding of threats to the attainment of food security in emerging countries. With a contribution to agricultural economics, the dissertation relies on value chain, market growth and price transmission theories and applies both panel data and time series econometric techniques to analyse the sources and magnitudes of the disruption of nutritional high-value food chains.The first part of the dissertation examines disruptions in unprocessed and minimally processed nutritional high-value food markets. Chapter 2 examines upstream and downstream disruptions along these food chains. Chapter 3 extends the analysis in Chapter 2 by assessing how disruptions change when nutritional high-value foods are highly processed. For each of the two chapters, disruptions are studied in terms of changes in upstream and downstream quantities and prices, with the disruption of quantity considered primary while that of prices is secondary.Using the São Paulo food market as a case study, Chapter 4 analyses the effect of diesel price shocks on different segments of the nutritional high-value food supply chain. A Vector Error Correction Model (VECM) that takes into account upstream and downstream cross-price effects is estimated to ascertain if diesel price shocks are higher downstream based on price transmission theory.The results of Chapters 2 and 3 show that climatological disasters are the most dominant source of disruption of nutritional high-value food supply chains and the direction of impact is negative for all foods under study. The magnitude of disruption, however, varies by food. From the VECM results in Chapter 4, we see that the price of diesel has a positive and significant effect on food prices, while the effects downstream are lower than those upstream. These results have significant implications for the design and implementation of food policies in emerging countries.As a general introduction, Chapter 1 justifies the need to study upstream and downstream differences in the magnitude of supply chain disruption, by situating the dissertation in the existing supply chain and food price transmission literature. Chapter 5 concludes the study and offers suggestions for future research
Guerreiro, Olinda Rosa Fragoso das Neves. "Inclusion of Cistus ladanifer in ruminant diets : an approach to improve the nutritional value of edible fats." Doctoral thesis, Universidade de Lisboa, Faculdade de Medicina Veterinária, 2018. http://hdl.handle.net/10400.5/15786.
Full textCistus ladanifer is a shrub quite abundant in Mediterranean countries, that when fed to lambs has been associated with changes in rumen biohydrogenation (BH), increasing t11-18:1 concentration in abomasal digesta and meat. The thesis main motivation was to further knowledge regarding C. ladanifer plant and to explore its utilization in nutritional strategies to ruminal BH modulation. In the first two experiments, seasonal variation of C. ladanifer aerial parts, with two ages, was characterized for chemical composition, including proximate composition and total phenols and condensed tannins (CT) contents, for in vitro digestibility, antioxidant activity and fatty acid (FA) profile. Cistus ladanifer was considered a nutritionally unbalanced feed, however, it may be used in ruminant nutrition, but only associated with other feeding resources to complement its nutritional imbalances. In third experiment, C. ladanifer fractions effects were tested on in vitro ruminal BH. Condensed tannins fraction was the most active on ruminal BH modulation, leading to a higher t11-18:1 accumulation and higher disappearance of substrate polyunsaturated FA. Therefore, we intended to determine which CT amount can optimize t11-18:1 ruminal synthesis. However, all CT fraction levels led to a depression of microbial growth without effects on ruminal BH. Last experiment was designed to explore effect of two levels of C. ladanifer CT (1.25% and 2.5%) and two ways of CT supply (C. ladanifer aerial parts and C. ladanifer CT extract) on lamb growth performance, carcass composition, meat quality and FA composition of lamb fat. The highest amount of C. ladanifer aerial part (2.5% of CT) had detrimental effects on growth performance, whereas, C. ladanifer CT extract inclusion in diet (1.25% of CT) led to the highest t11-18:1 increase in fat. So, we can conclude that C. ladanifer CT extract may be a good approach to improve the nutritional value of the ruminant edible fats.
RESUMO - Inclusão de Cistus ladanifer na dieta de ruminantes: uma abordagem para melhorar o valor nutricional das gorduras edíveis - As gorduras edíveis dos ruminantes têm sido associadas ao aumento do risco de doenças cardiovasculares, devido ao seu elevado conteúdo em ácidos gordos saturados, quantidades variáveis de ácidos gordos trans e baixo conteúdo de ácidos gordos polinsaturados. Este perfil de ácidos gordos (AG) resulta da bioidrogenação (BH) que os ácidos gordos polinsaturados da dieta sofrem no rúmen. Contudo, as gorduras edíveis dos ruminantes são naturalmente ricas em isómeros conjugados do ácido linoleico (CLA – conjugated linoleic acid), particularmente no isómero c9,t11-18:2, também designado por ácido ruménico. Diversos estudos in vitro e com modelos animais demonstraram que o c9,t11-18:2 possui atividades biológicas, como anti-inflamatória e anticarcinogénica. A manipulação da BH ruminal tem mostrado ser uma via para melhorar o valor nutricional das gorduras dos ruminantes, através do aumento da quantidade de ácidos gordos polinsaturados da dieta que escapam do rúmen sem sofrer alterações e do aumento da acumulação nos tecidos, e dos produtos dos intermediários da BH com efeitos benéficos, como CLA e do t11-18:1 (ácido vacénico), que é o principal precursor do c9,t11-18:2 nos tecidos. A inclusão de Cistus ladanifer L., um arbusto muito abundante na região Mediterrânea, em dietas à base de luzerna desidratada suplementada com 6% de óleos vegetais aumentou o t11-18:1 na digesta abomasal e na gordura intramuscular. Cistus ladanifer é rica em metabolitos secundários, que são compostos que não estão diretamente envolvidos nos processos de crescimentos, desenvolvimento e reprodução da planta, mas que contribuem para a adaptação e sobrevivência da planta. Contudo, a informação sobre a composição química da C. ladanifer é muito escassa, e não é claro qual a fração de C. ladanifer que possa ser responsável pela modulação da BH. A principal motivação desta tese foi aprofundar o conhecimento acerca da planta de C. ladanifer, e explorar a sua utilização em estratégias nutricionais para modular a BH ruminal. Nos dois primeiros ensaios, a variação sazonal das partes aéreas de C. ladanifer, com duas idades, foi caraterizada para a composição química, incluindo a composição proximal e o conteúdo em fenóis totais e taninos condensados (TC), para a digestibilidade in vitro, atividade antioxidante e perfil de AG. A parte aérea de C. ladanifer apresentou baixos teores de proteína, moderado conteúdo de constituintes parietais e baixa digestibilidade in vitro. Também foram encontrados na parte aérea da planta elevados teores em fenóis totais e TC, tendo estes aumentado durante o verão. A Cistus ladanifer é rica em AG saturados (73-82% do total de AG), e foram detetados pela primeira vez em arbustos dois AG de cadeia ramificada (iso-19:0 e iso-21:0), cujo conteúdo aumentou no verão e outono. Cistus ladanifer foi considerada como um alimento nutricionalmente desequilibrado, com teores elevados de fenóis totais e de TC. Contudo, pode ser utilizado na nutrição de ruminantes, mas apenas associado com outros recursos alimentares que complementem os seus desequilíbrios nutricionais. No terceiro ensaio, o efeito de cinco frações de C. ladanifer, ricas em metabolitos secundários, foi testado sobre a BH ruminal in vitro. Apesar de várias frações de C. ladanifer terem induzido alterações no perfil de AG, a fração de TC foi a fração mais ativa na modulação da BH ruminal, levando a uma maior acumulação de t11-18:1 e maior desaparecimento dos ácidos gordos polinsaturados do substrato. Após estes resultados pretendeu-se determinar a quantidade de TC de C. ladanifer que pode otimizar a síntese ruminal de t11-18:1. Contudo, quando testámos níveis crescentes de TC (entre 1,5 e 6% de TC, correspondendo ao valor máximo a mesma dose usada no ensaio anterior), todos os níveis de TC levaram a uma diminuição dos AG ramificados e dos dimetil acetais o que sugere uma redução do crescimento microbiano, sendo o efeito sobre a BH limitado. A BH do c9,c12,c15-18:3 sofreu uma ligeira redução com o aumento dos níveis de TC, sem efeito na produção de t11-18:1. Face aos resultados obtidos nos ensaios anteriores, o último ensaio foi delineado para explorar o efeito de dois níveis de TC de C. ladanifer (1.25% e 2.5%) e duas formas de fornecimento (parte aérea de C. ladanifer e extrato de TC de C. ladanifer) no desempenho produtivo, composição da carcaça, qualidade da carne e composição de AG da gordura de borregos. A incorporação dos níveis mais elevados de TC (2.5%) levou a efeitos prejudiciais no desempenho produtivo dos animais, especialmente com a inclusão da parte aérea de C. ladanifer, sem efeitos benéficos na composição de AG da gordura intramuscular e subcutânea. A inclusão de extrato de TC de C. ladanifer (1.25% de TC) na dieta levou ao aumento de t11-18:1 na gordura intramuscular e subcutânea, contudo, não afetou a concentração de c9,t11-18:2. Com esta tese podemos concluir que o extrato de TC de C. ladanifer pode ser uma boa abordagem para melhorar o valor nutricional das gorduras edíveis dos ruminantes.
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Mavimbela, David Thele. "The nutritional value of broiler litter as a feed source for sheep during periods of feed shortage." Thesis, Pretoria : [s.n.], 1999. http://upetd.up.ac.za/thesis/available/etd-12152006-153846.
Full textJasson, Timothy Ivan. "Effects of compost tea extract on growth, nutritional value, soil quality of Hypoxis hemerocallidea and Siphonochilus aethiopicus." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2791.
Full textThe exact responses to the concentration of compost tea extract and methods of irrigation application were not previously measured on Hypoxis hemerocallidea and Siphonochilus aethiopicus. Commercial exploitation, habitat loss and degradation, overharvesting, and enhancement of their medicinal properties, have led to this investigation and the need to replenish both these valuable plant species. This is crucial for plant survival, especially in the wild and for use of the traditional medicinal plants. Hypoxis hemerocallidea and Siphonochilus aethiopicus, known as star flower and wild ginger respectively continue to decline, due to overharvesting from their natural habitat. Both these species have tremendous traditional medicinal value among localized African people. To enhance their commercial cultivation, compost tea extracts, in the following ratios (no catalyst added (control1); T 1000:1, T750:1, T500:1, and T250:1L) were applied in equal dosages to determine an optimal compost tea extract ratio. The experiment was conducted in a temperature controlled greenhouse. Mushroom compost (500 g, per brew) was used for all extracts. Brewing was done with no catalyst added (Control 1), and 24 hours later another brew was done with catalyst added, weekly for 20 weeks. The Control treatment received water only. Both species were slow growing and comparatively, the Hypoxis plants responded faster than the Siphonochilus plants. In this investigation, plant growth parameters such as plant height, number of leaves, leaf width, leaf length and leaf colour, were measured and evaluated. Despite the plants positive response to the mushroom compost tea extracts, across all the above plant growth parameters, no significant differences were noted between the treatments during the twenty-week application period. Leaf chlorophyll content peaked in week 11 of the hypoxis plants and was the highest in week 14 of the Siphonochilus plants with no significant interaction between weeks vs. treatment over the twenty-week experiment. The chlorophyll readings indicate that both species increased their chlorophyll production over time. Although the total wet leaf length, root length, corm diameter, leaf weight, corm weight and root weight of Hypoxis were non-significant between treatments, T500:1 total wet weight was significantly higher when compared to the rest of the treatments. The total dry weight analysis of hypoxis was non-significant. Control Calcium level was significantly lower between the control and the treatments of the Hypoxis total dry leaf nutrient analysis. The Hypoxis dried roots nutrient analysis was non-significant across treatments.
Guadagnin, Matteo. "Nutritional value of canola expellers produced "on farm" by cold extraction of oil used as bio fuel." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3422576.
Full textObiettivo generale di questa tesi è stato quello di studiare e valutare il panello di colza (CE) estratto a freddo in impianti aziendali di piccole dimensioni per un potenziale utilizzo nell'alimentazione dei ruminanti. Nella tesi sono riportati i risultati di quattro prove sperimentali: nel primo contributo è stata valutata la stabilità della frazione lipidica del CE a temperature diverse e per diversi periodi di tempo al fine di valutare se la conservazione in condizioni anche particolari (durante la stagione estiva) in azienda, possa modificare il profilo degli acidi grassi e alcuni parametri di ossidazione lipidica. I risultati hanno evidenziato che a diverse temperature (12, 24, e 36°C) e tempi di stoccaggio (10, 20, e 30 d), CE ha mantenuto una buona stabilità ossidativa, come evidenziato dai bassi valori del numero di perossidi (<10 mEqO2/kg grasso), dal test di Kreis sempre negativo, e dalle scarse variazioni del contenuto di acidi grassi. Da questi risultati preliminari si può ipotizzare che lo stoccaggio aziendale per i panelli sottoprodotti ottenuti dal colza in azienda, non determina grosse variazioni della componente lipidica. Nel secondo contributo sono state valutate, in vitro, le produzioni di gas prodotti da campioni di CE e da semi di soia integrale incubando i questi alimenti con due differenti media: uno ricco in a N e uno senza N in modo da confrontare lâandamento delle fermentazioni quando lâunica fonte di N risulta lâalimento. I risultati hanno evidenziato che CE è una fonte proteica rapidamente degradabile; in caso di diete ipoproteiche come quelle suggerite per ridurre lâescrezione azotata, la sua inclusione potrebbe favorire l'attività microbica ruminale. Non sono sati rilevati effetti tossici sulla microflora ruminale durante la fermentazione dei due alimenti. Nel terzo contributo sono state confrontate in vitro quattro diete per bovini da carne a base di silomais con 2 livelli di inclusione di CE e WSS, in modo da ottenere un livello di proteina grezza paria al 15% e allâ11% PG sulla sostanza secca. In questa prova è stato utilizzato il sistema semicontinuo di fermentazione Rusitec. Le diete contenenti CE hanno mostrato una maggior (P <0.01) degradabilità dell'NDF, e prodotto meno (P <0.01) acetato e propionato ma più butirrato e acidi grassi ramificati. La produzione totale di AGV non è risultato diversa tra le due fonti proteiche. Il bilancio dellâN ha mostrato un maggior quantità (P <0.01) di arricchimento in15N nellâazoto non ammoniacale e valori tendenzialmente (P = 0.06) inferiori di N microbico derivato dall'uso di ammoniaca rispetto alle diete con inclusione di WSS. Nelle diete ad alto livello di inclusione i valori di arricchimento in 15N delle varie frazioni azotate sono risultati, come atteso, più alti (P <0.01) rispetto a quelle a basso livello di inclusione. In conclusione i due supplementi hanno mostrato andamenti fermentativi molto diversi. I due diversi livelli di inclusione hanno influito principalmente sulla disponibilità di proteina by pass senza effetti sulla sintesi microbica. Nel quarto contributo sono state testate, con la tecnica della gas production, le stesse quattro diete usate nel precedente esperimento. Eâ stato utilizzato il sistema RF Ankom® per testare la cinetica della produzione di gas nel corso della fermentazione. I risultati hanno mostrato che sia i valori di degradabilità dell'NDF che della SS sono stati maggiori (P < 0.05) per le diete contenenti CE rispetto a quelle con WSS e, come atteso, sono risultati inferiori nella diete a basso livello di inclusione delle due fonti proteiche. Le diete CE sono state caratterizzate da una produzione oraria di gas superiore (P < 0.05) in, ma non è variata la quantità totale di gas prodotto. La riduzione del livello di CP da 15 all'11% SS ha diminuito il tasso di produzione di gas ma non la quantità totale. Il contenuto di ammoniaca nel liquido ruminale al termine dellâincubazione è risultato più alto (P < 0.001) nelle diete ad alto livello di inclusione. Concludendo possiamo affermare che con diete a basso livello di proteina, l'uso di CE in sostituzione alla soia, può migliorare la velocità di degradazione durante le prime ore di fermentazione. In generale, il panello di colza ottenuto per estrazione a freddo in azienda potrebbe essere un alimento interessante nell'alimentazione dei ruminanti con effetti favorevoli sia dal punto di vista economico che ambientale
Bvenura, Callistus. "Wild vegetables of the Eastern Cape of South Africa: the nutritional value and domestication of solanum nigrum l." Thesis, University of Fort Hare, 2014. http://hdl.handle.net/10353/d1015514.
Full textWalker, Keitirele Patricia. "Productivity of four fodder tree species, their nutritional value and potential role in ruminant production in Eastern Botswana." Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/1421.
Full textSustainable livestock production in semi-arid Botswana could be improved through tree planting on-farm to provide much needed protein and shade. Such action can be encouraged if the growth, productivity, nutritional value of trees and their contribution to mass gain of livestock are known.. A study at Malotwana investigated two indigenous species, Acacia galpinii and Faidherbia albida, and two exotic species, Leucaena diversifolia and L. leucocephala, at three spacings in a randomised complete block design replicated five times. The three spacings represented 400, 317 and 241 trees per hectare. The study was conducted over 6.5 years. Indigenous trees were sampled biennially and exotics annually to evaluate crown width, height, stem diameter, stem number and stem volume index. Complete plant harvesting of exotic trees at 2.5, 4.5 and 6.5 years evaluated agroforestry production. Leaves from all four species and pods of exotic species were analysed for chemical composition. Two groups of eight lambs were balanced for mass at selection for an on-farm feeding trial. Browse from exotic trees, comprising a 2:1 ratio of pods to leaves, was fed at 30% as supplement to hay to one group whose mean mass was contrasted with that of the control group fed sorghum bran at 30%. A. galpinii was a promising species, adaptable to planting away from its origin. Its crown width ranged from 5.86 m in high density plots to 6.08 m at low density and was significantly different among stands (p = 0.0406) at 6.5 years. Diameter at breast height (dbh) was significantly different among stands aged 6.5 years (p = 0.0003) and ranged between 10.38 cm at high density to 12.48 cm in low density plots, demonstrating a capacity to provide both shade and poles on-farm. At 4.5 years, F. albida attained a mean height of 4.5 m and 4.5 cm in dbh but suffered 67% mortality during a severe drought. Annual fodder production of 0.647 and 0.996 metric tonnes ha-1 for leaves and pods of L. diversifolia and 1.237 and 1.431 for L. leucocephala was recorded in years of average rainfall. Yields of 0.3 and 0.59 metric tonnes ha-1 were recorded for both species in the driest year. Equally good agroforestry production was obtained from both low and high density stands suggesting that low density plantings, which foster higher plant survival and reduce disease incidence, are best suited to the semi-arid conditions of Botswana. The crude protein of leaves ranged between 16.26 (L. diversifolia) and 25.25% (F. albida). They were highly digestible with more than twice the calcium content livestock require. Crude protein and digestibility measures were significantly different among leaves and varied significantly at different spacings (p<0.0001). Pods of the exotic species contained significantly more protein than the leaves (p<0.0001). Lambs supplemented with browse gained 102.33 g per animal per day while the control group gained 83.95 g. There were significant differences between groups during growth (p<0.05). Growing of A. galpinii, complemented with L. diversifolia and L. leucocephala, can supply short and long term feed, and greatly enhance livestock production while diversifying farm feed sources
Abazinge, Michael D. A. "Studies of methods of preserving and enhancing fermentation, nutritional value and palatability of seafood waste for feeding ruminants." Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/49972.
Full textHamilton, Jeffrey Muir. "Arugula Crop Production in Arid and Semi-Arid Regions: Nutritional Value, Postharvest Quality, and Sustainability in Controlled Environments." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/195968.
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