Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this research was to evaluate the productivity and nutritive value of elephant grass pastures, subjected to conventional and organic production system. In the conventional system elephant grass was planted in rows 1.2 m apart from each other. In the organic system elephant grass was planted in rows 3 m apart from each other. In the space between rows, in cool season, annual ryegrass was sown; allowing the development of spontaneous growing species in the warm season. It was applied 100 kg of N/ha from chemical and organic fertilizers (manure of cattle and pig slurry) in the respective pastures. The grazing method was rotated with time to occupy the two days. Holstein cows receiving 0.9% of body weight complementary concentrate feed were used. Pre and post grazing forage mass, botanical and structural composition, forage production and stocking rate were evaluated. Hand-plucked samples were collected to analyze chemical composition and digestibility. Experimental design was completely randomized with two treatments (forage systems), three replicates (paddocks) and repeated measures (mean values of grazing cycles or season). Eight and seven grazing cycles were performed during the experimental period for respective systems. Organic system present best forage distribution thought the year and highest participation of elephant grass leaf blades on herbage mass. The pasture under conventional system presented higher forage mass and stocking rate. Similar value was found in the chemical composition and digestibility of elephant grass pastures in both pasture systems. The organic as much as conventional system showed high qualitative values considering the fertilization, manage and utilization time, in proposed strategy. The results show that the elephant grass can be used under the organic system proposed. / Objetivou-se com esta pesquisa avaliar a produtividade e o valor nutritivo de pastagens de capim elefante submetidas aos sistemas de produção orgânico e convencional. No sistema convencional, o capim elefante foi plantado em linhas afastadas a cada 1,2 m. No sistema orgânico, o capim elefante foi plantado em linhas afastadas a cada 3 m; no espaço entre as linhas, no período hibernal, foi semeado o azevém anual e, no período estival, permitiu-se o desenvolvimento de espécies de crescimento espontâneo. Foram utilizados 100 kg de N/ha com fertilizantes químico e orgânico (esterco de bovino e chorume de suínos) para os respectivos sistemas de produção. O método de pastejo adotado foi o rotacionado, com tempo de ocupação de um ou dois dias, utilizando vacas em lactação que receberam complementação alimentar com concentrado à razão de 0,9% do peso vivo. Foram avaliados a massa de forragem de pré-pastejo e pós-pastejo, composições botânica e estrutural, taxa de desaparecimento, e de acúmulo, produção de forragem e carga animal. Para a determinação da composição química e digestibilidade da forragem, foram retiradas amostras simulando o pastejo. O delineamento experimental foi o inteiramente casualizado com dois tratamentos (sistemas forrageiros), com três repetições (piquetes) e com medidas repetidas (valores médios dos pastejos em cada ciclo ou estação do ano). Durante o período experimental, foram conduzidos oito e sete pastejos para os respectivos sistemas. Na pastagem sob o sistema orgânico, houve melhor distribuição de forragem e maior participação de lâminas foliares do capim elefante na massa de forragem. Na pastagem sob o sistema convencional, verificaram-se maiores valores de produção de forragem e carga animal. Valores similares foram observados quanto à composição química e digestibilidade do capim elefante em ambos os sistemas. Na estratégia proposta, tanto no sistema orgânico quanto no convencional apresentaram teores qualitativos elevados, considerando-se a adubação, manejo e tempo de utilização. Os resultados demonstram que o capim elefante pode ser utilizado segundo o sistema de produção orgânico proposto.

Made available in DSpace on 2014-07-29T15:07:59Z (GMT). No. of bitstreams: 1 Dissertacao Debora de Carvalho Basto.pdf: 1304650 bytes, checksum: c7c0508fd8367c1bd05d4f268711e1ef (MD5) Previous issue date: 2010-03-22 / The best height of forage at time of entry into pasture and the height of forage millet residue for grazing are still controversial. This experiment was conducted at the Department of Animal Production of the Veterinary School, of Federal University of Goias, in Goiania-GO, from January to May 2009, and aimed to evaluate the productive potential and the chemical composition of three cultivars of forage millet (Pennisetum glaucum (L.) R. BR.) under different heights of entry and of the stubble. The 27 treatments consisted of the combinations of three varieties of millet - ADR 500, H733/07 and H729/07, allocated in plots, three heights at entry (0.50, 0.60 and 0.70 m) and three heights of stubble (zero, 0.10 and 0.30 m) allocated in sub-plots with four replications, totaling 108 experimental units. A randomized complete block design, with split plots andfour replications in a 3 x 3 x 3 factorial arrangement was used. Green matter total yield (GMTY), dry matter total yield (DMTY), average production of dry matter per cutting, production of dry matter of stubble with zero, 0.10 and 0.30 m, average rate of forage accumulation, and rate of forage accumulation of stubble "zero" 0.10 and 0.30 m were determined. The contents of crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were also determined. Green matter total yield (GMTY) differed depending on the height at entry (HE) and height of stubble, with average values of 25.2: 28.0 t ha-1 and 28.5 and 20.4; 30.6 and 30.7 t ha-1, estimated for the HE and stubble, respectively. The dry matter production increased in the extent that the height at entry and the height of the stubble increased. The average production of dry matter per cutting for the cultivars was approximately 2840 kg ha-1/DM. The average accumulation of forage millet was 61.74, 58.29 and 63.59 kg ha-1/DM for cultivars ADR-500, ADR-500 hp, 729 and 733, respectively. Regarding chemical composition, the dry matter content did not differ among the cultivars evaluated. The CP did not differ in function of the cultivars and HE. The residue of 0.10 and 0.30 m, interactions among cultivar x HE x cutting, averaging 14.0% of CP were observed. The NDF had triple interaction: cultivar x HE x cutting in the stubbles of 0.10 and 0.30 m, with average values of 57.6, 58.6 and 57.7%, and 58.4, 61, 6 and 57.7%, respectively. ADF differed in relation to the cultivars, with values of: ADR-500-35- 5, 729 - 37.6 and 733 - 37.9%. As for the residue of 0.10 m, there was an interaction in relation to HE x cutting, with values of 30.0, 31.7 and 25.8% for the HE of 0.50, 0.60 and 0.70 m. As for the residue of 0.30 m triple interactions were observed: HE x cultivar x cutting, with average rates of (ADR-500) - 31.7%, (729) - 32.0%, and (733) - 32.7%, respectively. Based on the values of dry matter and chemical composition, all cultivars showed potential for use in animal feed. / Ainda é controversa a melhor altura de entrada e do resíduo do milheto forrageiro para fins de pastejo. O presente experimento, foi conduzido nas dependências do Departamento de Produção Animal da Escola de Veterinária da Universidade Federal de Goiás, no município de Goiânia-GO, durante o período de janeiro à maio de 2009, teve como objetivo avaliar o potencial produtivo e a composição bromatológica de três cultivares de milheto forrageiro (Pennisetum glaucum (L.) R. BR.) sob alturas de entrada e do resíduo pós-pastejo. Os 27 tratamentos corresponderam às combinações de três cultivares de milheto - ADR 500, H733/07 e H729/07, alocados às parcelas, três alturas de entrada (0,50, 0,60 e 0,70 m) e três alturas de resíduo (zero, 0,10 e 0,30 m) alocados nas sub-parcelas, com quatro repetições, totalizando 108 unidades experimentais. Utilizou-se o delineamento experimental em blocos completos ao acaso, com parcelas subdivididas no tempo e quatro repetições em esquema fatorial 3 x 3 x 3. Determinou-se as produções totais de massa verde (PTMV) e massa seca (PTMS), produção média de massa seca por corte, produção de massa seca com resíduos zero , 0,10 e 0,30 m, taxa média de acúmulo de forragem, taxa de acúmulo de forragem com resíduo zero 0,10 e 0,30 m do solo. Foram determinados os teores de proteína bruta (PB), fibra em detergente neutro (FDN) e fibra em detergente ácido (FDA). A produção de massa verde total(PMVT) diferiu em função das alturas de entrada (AE) e dos resíduos de corte, com valores médios de 25,2: 28,0 e 28,5 t.ha-1 e 20,4; 30,6 e 30,7 t.ha-1, determinados para as AE e resíduos, respectivamente. A produção de massa seca se mostrou crescente a medida em que se aumenta a altura de entrada e do resíduo póspastejo. A produção média de massa seca por corte para os cultivares foi da ordem de 2.840 kg.ha-1 de MS. Já a taxa média de acúmulo de forragem do milheto foi de 61,74;58,29 e 63,59 kg.ha-1 de MS para os cultivares ADR-500, cv ADR-500, 729 e 733, respectivamente. Em relação à composição químicobromatológica, os teores de matéria seca não diferiu entre os cultivares avaliados. Os teores de PB não diferiram em função dos cultivares e AE. No resíduo de 0,10 e 0,30 m, foram observadas interações entre cultivar x AE x corte, com médias de 14,0% de PB. Os teores de FDN apresentaram interação tripla: cultivar x AE x corte, nos resíduos de 0,10 e 0,30 m, com valores médios de 57,6; 58,6 e 57,7% e de 58,4; 61,6 e 57,7%, respectivamente. Os teores de FDA diferiram em relação aos cultivares, com valores de: ADR-500-35,5; 729- 37,6 e 733- 37,9%. No resíduo de 0,10 m, houve interação em relação à AE x corte, com valores de 30,0; 31,7 e 25,8%, nas AE de 0,50; 0,60 e 0,70 m, enquanto no resíduo de 0,30 m, foram observadas interações tripla: cultivar AE x corte, com teores médios (ADR- 500) 31,7%; (729) 32,0% e (733) 32,7%, respectivamente. Tomando por base os valores de produção de massa seca e composição bromatológica, todos os cultivares apresentaram potencial para serem utilizados na alimentação animal.

Les hydrocarbures aromatiques polycycliques (HAP) sont des polluants organiques persistants qui sont présents en mélange complexe dans l’environnement et notamment dans les milieux aquatiques. Ils s’adsorbent sur les particules en suspension, s’accumulent dans les sédiments et dans les premiers maillons de la chaîne trophique. L’objectif de cette étude était de mesurer les effets à long terme d’une contamination par des HAP chez un modèle de vertébrés : le poisson zèbre. Dans un premier temps, des embryons ont été exposés pendant les 4 premiers jours de leur développement sur du sédiment naturel enrobé de 3 HAP individuel (phénanthrène, pyrène et benzo[a]pyrène) puis transférés et élevés en eau propre. Dans un deuxième temps, des poissons ont été exposés par voie alimentaire tout au long du cycle de vie et dès le premier repas à 3 fractions de HAP à doses environnementales enrobées sur les aliments : une fraction pyrolytique (PY) extraite d’un sédiment échantillonné dans la Seine et deux fractions pétrogéniques (un fuel lourd (HO) provenant de l’Erika et un pétrole brut type Arabian light (LO)). Les effets à long terme sur la croissance, la survie, la reproduction et le comportement ont été évalués à différents âges. Ces effets ont pu être observés à plusieurs échelles, i.e. de la molécule, aux tissus et organes puis à l’échelle de l’individu. Globalement, chez les poissons contaminés, la croissance est ralentie, la survie larvaire diminuée chez les HO, la fonction reproduction est altérée fortement à la fois au niveau hormonal, tissulaire et phénotypique ainsi que les réponses comportementales léthargiques ou hyper-réactives selon les cas. L’exposition par voie sédimentaire a révélé des effets visibles lorsque les individus atteignaient 6 mois soulignant l’existence d’effets tardifs, notamment sur les réponses comportementales, d’une exposition très précoce y compris chez la descendance. Quant à l’exposition par voie alimentaire, elle a montré une gradation des effets. Toutes fonctions confondues, les résultats obtenus permettent d'établir une hiérarchie dans la toxicité des fractions étudiées : PY < LO ≈ HO. L'approche multi-échelle utilisée dans ce travail a permis, en partant d'informations acquises au niveau moléculaire, tissulaire et individuel, d'aboutir à une compréhension intégrée des conséquences qu'une exposition à des HAP peut avoir sur l'aptitude à la survie des poissons dans leur milieu naturel ainsi qu'à leur capacité à participer au renouvellement des générations futures. / Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants (POPs) which are found in complex mixtures in the environment including aquatic ecosystems. They adsorb on particles, accumulate in sediment and in the first link of the food web. The aim of this study was to measure long term effects of PAHs contamination on a vertebrate model : the zebrafish. In a first study, embryos were exposed on natural sediment spiked with 3 individual PAH (phenanthrene, pyrene and benzo[a]pyrene) during the first four days of their development. In a second study, to evaluate the consequences of long-term chronic exposure to PAHs, zebrafish were exposed, from their first meal (5 days post fertilisation) until they became reproducing adults, to diets spiked with three PAHs fractions at environmentally relevant concentrations (0.3X, 1X and 3X; with the 1X concentration being in the range of 4.6-6.7 μg.g-1 for total quantified PAHs). The fractions used were representative of PAHs of pyrolytic (PY) origin or of two different oils of differing compositions (a heavy fuel (HO) and a light crude oil (LO)). Long term effects on growth, survival, reproduction and behavior were evaluated at different ages. Effects were observed at molecule, tissue, organ and individual scales. In general, for contaminated fish, growth was reduced, larval survival decreased in HO, and reproduction was strongly impaired at hormonal, tissue and phenotypic levels, and behavioral responses were lethargic or hyperactive depending on fractions and stages. Sediment exposure still revealed visible effects when fish were 6 month old. These results hereby showed significant late effects, especially in behavioral responses after an early exposure, including in larvae issued from contaminated fish. In spiked diets contaminated fish, we observed a gradation of effects. Combining all functions, we established of hierarchy in toxicity in the studied fractions: PY < LO ≈ HO. Finally, our results gathered at a multiscale from molecule, to tissue and individuals, indicate that PAH mixtures of different compositions, representative of situations encountered in the wild, can promote lethal and sublethal effects which are likely to be detrimental for fish survival and recruitment into future generations.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this research was to evaluate tree pasture-based systems (PS) with elephant grass (EG) + spontaneous growing species (SGS), ryegrass (RG), for PS1; EG + SGS + forage peanut, for PS2; and EG + SGS + RG + red clover, for PS3. EG was planted 4 m spaced rows. In the cool-season, ryegrass was sowed between rows of EG; red clover was sowed and the forage peanut was preserved in respectively PS. Experimental design was completely randomized with tree treatments (SF), two replicates (paddocks) in completely split-plot time (grazing cycles). Holstein cows receiving 5.5 kg-daily and a complementary concentrate feed were used in the evaluation. The herbage mass parameters, botanical composition, forage production and stocking rate were evaluated. Samples were collected by the hand-plucking method to analyze the organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and organic matter in situ digestibility (OMISD) of pasture; phenols and tannins on legumes. Nine grazing cycle were performed during the experimental period (341 days). The mean values of forage production, stocking rate, crude protein and digestibility were 17.14; 16.80; and 19.47 t/ha; 3.28; 3.34; and 3.60 UA/ha; 13.86; 15.39; and 14.78%; 78.33; 79.23; and 79.94% on the respective PS. SGS increased significantly (P≤0,05) relation to the PS without forage legume. Similar results were observed for forage production OM an NDF in comparison to PS. Nutritive value was similar between forage legumes. Differences (P≤0,05) on condensed tannin tenors were observed between forage legumes. Considering the forage production, stocking rate and nutritive value, the PS mixed to forage legumes showed better performance. / O objetivo desta pesquisa foi avaliar três sistemas forrageiros (SF) com capim elefante (CE), espécies de crescimento espontâneo (ECE), azevém anual (AZ), como SF1; CE + ECE + AZ + amendoim forrageiro (AF), como SF2; e CE + ECE + AZ + trevo vermelho (TV), como SF3. O capim elefante foi estabelecido em linhas afastadas a cada 4 m. No período hibernal fez-se o estabelecimento do AZ entre as linhas do capim elefante; o trevo vermelho foi semeado e o amendoim forrageiro foi preservado, considerando os respectivos tratamentos. O delineamento experimental foi o inteiramente casualizado, com três tratamentos (SF), duas repetições (piquetes) em parcelas subdivididas no tempo (pastejos). Para avaliação foram usadas vacas da raça Holandesa que receberam complementação alimentar com concentrado à razão de 5,5 kg/dia. Foram avaliados parâmetros da massa de forragem pré-pastejo, a composição botânica, a produção de forragem e a lotação. Para analisar a matéria orgânica (MO), a fibra em detergente neutro (FDN), proteína bruta (PB) e digestibilidade in situ da MO (DISMO) da pastagem e os teores de fenóis e taninos das leguminosas, foram coletadas amostras de pastejo simulado. Durante o período experimental (341 dias) foram efetuados nove ciclos de pastejo. Os valores médios de produção de forragem, lotação, PB e de DISMO foram 17,14; 16,80; e 19,47 t/ha; 3,28; 3,34; e 3,60 UA/ha; 13,86; 15,39; e 14,78%; 78,33; 79,23; e 79,94% nos respectivos SF. Houve aumento significativo (P≤0,05) para espécies de crescimento espontâneo na pastagem sem leguminosa. Resultados similares foram observados entre SF para MO e FDN. O valor nutritivo foi similar entre as leguminosas forrageiras. Foram observadas diferenças (P≤0,05) entre as leguminosas para os teores de taninos condensados. Considerando a massa de forragem, a lotação e o valor nutritivo, as pastagens consorciadas com leguminosas forrageiras apresentaram melhor desempenho.

Reliable energy supply is a major concern and crucial for development of the global society. To address the dependency on fossil fuel and the negative effects of this reliance on climate, there is a need for a transition to cleaner sources. An attractive solution for replacing fossil-based products is renewable substitutes produced from biomass. Gasification and pyrolysis are two promising thermochemical conversion technologies, facing challenges before large-scale commercialization becomes viable. In case of biomass gasification, tar is often and undesired by-product. An attractive option to convert tar into syngas is nickel-based catalytic steam reforming (SR). For biomass pyrolysis, catalytic SR is in early stages of investigation as a feasible option for bio-crude conversion to syngas. The focus of the thesis is partly dedicated to describe research aimed at increasing the knowledge around tar reforming mechanisms and effect of biomass-derived impurities on Ni-based tar reforming catalyst downstream of gasifiers. The work focuses on better understanding of gas-phase alkali interaction with Ni-based catalyst surface under realistic conditions. A methodology was successfully developed to enable controlled investigation of the combined sulfur (S) and potassium (K) interaction with the catalyst. The most striking result was that K appears to lower the sulfur coverage and increases methane and tar reforming activity. Additionally, the results obtained in the atomistic investigations are discussed in terms of naphthalene adsorption, dehydrogenation and carbon passivation of nickel. Furthermore, the thesis describes research performed on pyrolysis gas pre-conditioning at a small-industrial scale, using an iron-based catalyst. Findings showed that Fe-based materials are potential candidates for application in a pyrolysis gas pre-conditioning step before further treatment or use, and a way for generating a hydrogen-enriched gas without the need for bio-crude condensation. / Tillförlitlig energiförsörjning är en stor utmaning och avgörande för utvecklingen av det globala samhället. För att ta möta beroendet av fossil råvara och de negativa effekter som detta beroende medför för klimatet finns ett stort behov av en övergång till renare energiråvaror. En attraktiv lösning är att ersätta nuvarande fossil råvara med produkter från biomassa. Förgasning och pyrolys är två lovande teknologier för termokemisk omvandling av biomassa. Kommersialisering av dessa teknologier är inte helt problemfritt. I fallet förgasning så behöver, bl.a. oönskade tyngre kolväten (tjära) hanteras innan den producerade orenade produktgasen kan användas i syntesgastillämpningar. Ett effektivt alternativ för detta är gaskonditionering vid höga temperaturer, baserade på katalytisk ångreformering med en nickelkatalysator. Katalytisk ångreformering är en möjlig teknik för omvandling av bioråvara, producerad från pyrolys av biomassa, till syntesgas. Avhandlingen fokuserar delvis på att beskriva den forskning som utförts för att öka kunskapen kring mekanismer för tjärreformering och effekterna av föroreningar från biomassan på en nickelkatalysator nedströms förgasare. Arbetet bidrar till en bättre förståelse av hur alkali i form av kalium (K) i gasfasen upptas, jämviktas och växelverkar med ytan hos nickelkatalysatorn under fullt realistiska förhållanden. Inledningsvis utvecklades en metod för att möjliggöra kontrollerade studier av den kombinerade effekten av S och K, vilken inkluderar exakt dosering av alkali till en produktgas, eliminering av transienter i katalysatoraktiviteten samt katalysatorkarakterisering. Det mest lovande resultatet är att K både sänker ytans svavelinnehåll och ökar aktiviteten för omvandlingen av metan och tjära. För att ytterligare fördjupa kunskaperna i mekanismerna för tjärnedbrytning utfördes experimentella och teoretiska ytstudier på en enkristallnickelyta med naftalen som modellförening. Resultat avseende naftalenadsorption, dehydrogenering av naftalen och kolpassivering av nickelytan diskuteras. Därutöver så beskriver avhandlingen den forskning som utförts inom förkonditionering av pyrolysgas med en järnkatalysator för varsam deoxygenering av biooljan och vätgasproduktion. Detta utfördes vid en småskalig industriell anläggning. De experimentella studierna visar att den undersökta järnkatalysatorn resulterar i en vätgasberikad gas och att den är en potentiell kandidat för tillämpning i ett förkonditioneringssteg. / <p>QC 20170830</p>

Integrated aquaponic food production systems are capable of producing more food on less land using less water than conventional food systems, and marine systems offer the potential of conserving freshwater resources. However, critical factors such as suitable species combinations, environmental conditions (salinity and pH), and nutrient management (animal to plant ratio, C/N ratio, and dietary crude protein) have not been fully understood for marine systems. There were four objectives in this project. The first objective was to evaluate the growth performance of potential comparable combination (whiteleg shrimp with three halophytic plants) for the development of marine aquaponics with BFT under different salinities. The second objective was to evaluate stocking densities and the C/N ratio on growth and production of whiteleg shrimp and three halophytes. The third objective was evaluation of varying concentrations of dietary crude protein in practical diets fed to shrimp raised in biofloc aquaponic saltwater systems. The fourth objective was to evaluate effects of pH levels and additional C on the growth and production of whiteleg shrimp and five plant species in marine aquaponics. Four conclusions were determined: 1) Regarding marine aquaponics, whiteleg shrimp and the three halophytes (Atriplex hortensis, Salsola komarovii, and Plantago coronopus) are suitable combinations for future development. According to the research results, shrimp performed better in a salinity of 15 and 20 ppt; yet, plants performed better in a salinity of 10 and 15 ppt. Therefore, a salinity of 15 ppt is suggested as the optimal saline condition for shrimp and the three halophytes in an indoor marine aquaponics system. In addition, inoculating probiotics do have the efficiency of stabilizing water quality, cultivating microbial community, and enhancing the health of shrimp and plants in the operation of aquaponics. 2) The stocking density ratio and C/N ratio exerted significant impacts on the performance of shrimp and plants in marine aquaponics. Shrimp performed better with the stocking density of 2:1 and 3:1, with no impact from the C/N ratio. Conversely, plants performed better with the stocking density of 3:1 and 5:1 with the C/N ratio at 15. Therefore, a stocking density ratio of 3:1 with a C/N ratio at 15 is suggested as the optimal condition for shrimp and the three halophytes in an indoor marine aquaponic food production system. Inoculating the water with biofloc and applying probiotics regularly can enhance the management of water quality and the health of shrimp and plants in aquaponics. 3) Among the findings of the study, shrimp growth was not affected by the protein content of the feed, suggesting that it is possible to use feeds with lower protein concentration when culturing shrimp in biofloc-based marine aquaponics. However, plants grew better in the treatments with higher protein content feed in the early and middle stages of production. Hence, for maximum production, providing a higher protein concentration feed (35 %) in the early stages of system start-up, and switching to a lower protein concentration feed (30 %) in the later stages of cultivation might be feasible. 4) The current study found no significant effects of pH or additional C on shrimp performance. In contrast, plants grew better in lower pH treatments, while additional C supplements improved the performance of plants grown in higher pH treatments and had similar results to the lower pH treatments. We suggest that RO water is not suitable source of water for shrimp-based marine aquaponics if ionic composition is not managed. The addition of C, however, led to improved growth and yields of most plants. Hence, adding C can be a promising approach in marine aquaponics to enhance the resistance to the abiotic stress of plants and improve their growth.<div> <br>The present study on marine aquaponics has produced important findings that will fill some knowledge gaps, provide management guidelines for production, and facilitate its development. <br></div>

MSCAGR (Animal Science) / Department of Animal Science / The objective of the study was to determine the effects of fertilisation with bio-digester slurry and the inclusion of carbohydrate additives at ensiling on the fermentation characteristics, chemical composition, ruminal degradability, and in vitro digestibility of Napier grass silage. Napier grass planted at the School of Agriculture Experimental Farm, University of Venda in 5 m x 4 m plots replicated three times in a completely randomised design and was irrigated with either biodigester slurry or no bio-digester slurry (tap water) for a period of 12 weeks. After 12 weeks, the Napier was freshly cut and ensiled for 90 days in 1 litre glass jars in a 2 (Control - tap water and slurry irrigation) x 4 (No additive, molasses, maize meal and brown sugar) factorial arrangement. Fermentation quality and nutritive composition were determined using standard protocols. The dry matter (DM) and crude protein (CP) ruminal degradability was determined in sacco by incubating feed samples in nylon bags (external dimension: 6 × 12 cm, pore size of 46 μm) in the rumen in three Bonsmara steers fitted with rumen cannulae for 0, 6, 12, 24, 48, 72, 96 and 120 hours (h). Parameters to describe the dynamics of ruminal degradability of DM and CP were obtained by fitting the data on the exponential equation P = a + b (1 - e-ct) using the NEWAY computer program, where “a” is the rapidly degradable fraction, “b” is the slowly degradable fraction and “c” is the outflow rate. The in vitro DM and CP degradability of rumen undegradable residue collected after 12, 24 and 48 h incubation was determined by sequential digestion in pepsin (abomasal) and pancreatin (small intestine) solutions. Fertilisation with bio-digester slurry increased (P <0.05) CP content of fresh cut Napier grass pre-ensilage. Bio-digester slurry fertilisation with molasses inclusion improved (P <0.05) the silage DM content which improved (P >0.05) fermentation characteristics with pH of 4.2 and lowest NH3-N of 13.3 g/kg. Other chemical compositions and fermentation characteristics were not affected (P >0.05) due to fertilisation x additives treatment combinations. No bio-digester slurry fertilisation with maize meal inclusion increased (P <0.01) DM degradability at 0 h incubation. As time progressed to 24 h, no biodigester slurry fertilisation with no additive included reduced (P <0.01) DM degradability with no difference (P >0.05) on other treatments. Potential DM degradability (a + b) of no bio-digester slurry fertilisation with no additive inclusion silage was reduced (P <0.01). The reduction was associated with low levels (P <0.01) of slowly degradable fraction “b”. In vitro DM and CP digestibility were not affected (P >0.05) due to fertilisation x additives treatment combinations. In conclusion, bio-digester slurry application improved the quality of fresh cut Napier grass, with the combination of bio-digester slurry fertilisation and molasses addition yielding the best silage quality.

MSCAGR (Animal Science) / Department of Animal Science / Forage and browse legumes play an important role in sustaining livestock in small holder farming systems in the tropics, mainly as a result of their contribution to economic and environmental sustainability of livestock production. The study was conducted to determine the chemical composition, ruminal degradability and in vitro digestibility of dry matter (DM) and crude protein (CP) of Dichrostachys cinerea and Bauhinia thonningii leaves. The browse tree leaves were harvested in the wild in Shayandima, Limpopo province. The leaves were collected, oven-dried, milled to pass through a 1.0 mm sieve and analysed for chemical composition in the Animal Science Nutrition Laboratory, at the University of Venda. The browse tree leaves were analysed for DM nitrogen, neutral detergent fibre (NDF) and acid detergent fibre (ADF). Approximately 5 g of leaf sample milled to pass through through a 1 mm sieve were placed in nylon bags (external dimension: 6 × 12 cm, pore size of 41 μm) and incubated in duplicates for 0, 4, 8, 16, 24, 48, 72, 96 and 120 hours periods in the rumen of three cannulated Bonsmara steers. The residues were then analysed for DM and nitrogen. Parameters to describe the dynamics of ruminal degradability of DM and CP were obtained by fitting the data on the exponential equation P = a + b (1 - e-ct) using NEWAY computer program, where “a” is the rapid degradable fraction, “b” is the slow degradable fraction and “c” is the outflow rate. The in vitro DM and CP degradability of rumen undegradable residue collected after 24 and 48 hour incubation was determined by sequential in vitro digestion in pepsin (abomasal) and pancreatin (small intestine) solutions. DM and CP content differed significantly (P ˂ 0.05). D. cinerea leaves had higher levels of DM and CP content than B. thonningii leaves. DM and CP disappearance increased (P < 0.01) as the incubation period increased. There was no difference (P > 0.05) in soluble fraction ‘a’ and ‘b’ of DM of the two species. The CP components for both fraction ‘a’ and ‘b’ differed significantly (P < 0.01) for CP among the two species. There was significant difference (P < 0.01) in post-ruminal digestibility among the two species. CP digestibility of B. thonningii and D. cinerea leaves was reduced (P < 0.01). In conclusion, B. thonningii and D. cinerea leaves showed significant difference based on their fermentation kinetics and in vitro digestibility, suggesting a good nutritional quality which can be used as protein source for ruminants in dry season and supplement to low-quality diets. / NRF

To achieve a shared blueprint for peace and prosperity for people and the planet, the United Nations has defined the 2030 Agenda for Sustainable Development, including economic, social, and environmental sustainability as three pillars. This thesis work is aimed at building a sustainability evaluation framework to investigate the product, which in this study is transformer insulating liquid. What’s more, this study focuses on the sustainability evaluation of the extraction step of the raw material which is crude oil and vegetable oil for insulating liquids. The evaluation method is based on the triangular fuzzy number variables, which represent the ambiguity of linguistic variables. Meanwhile, the sustainable development goals are discussed and developed into feasible evaluation criteria. According to the defined criteria, the performance of each indicator is taken from published literature, reports, and official organization. After that, the sustainability index of each oil is calculated and compared, thus a general sustainable result is given. The result shows that mineral oil is more sustainable than vegetable oil only in economic sustainability, while in other aspects including the overall aspect vegetable oil is more sustainable than mineral oil. Among that, mineral oil performs most weakly in environmental sustainability, while vegetable oil is in economic sustainability. Furthermore, the framework designed is expected to be used to evaluate the entire life cycle of a product and can be referred to in future supply chain improvement, since more indexes can be developed based on the mathematics fuzzy number calculation principle. / För att uppnå en gemensam plan för fred och välstånd för människor och planeten har FN definierat 2030-agendan för hållbar utveckling, inklusive ekonomisk, social och miljömässig hållbarhet, som tre pelare. Detta examensarbete syftar till att bygga ett ramverk för hållbarhetsutvärdering för att undersöka produkten, som i denna studie är transformatorisoleringsvätska. Dessutom fokuserar denna studie på hållbarhetsutvärderingen av utvinningssteget av råmaterialet som är råolja och vegetabilisk olja för isolerande vätskor. Utvärderingsmetoden är baserad på de triangulära luddiga talvariablerna, som representerar tvetydigheten hos språkliga variabler. Samtidigt diskuteras målen för hållbar utveckling och utvecklas till genomförbara utvärderingskriterier. Enligt de definierade kriterierna är prestandan för varje indikator hämtad från publicerad litteratur, rapporter och officiell organisation. Därefter beräknas och jämförs hållbarhetsindexet för varje olja, vilket ger ett generellt hållbart resultat. Resultatet visar att mineralolja är mer hållbar än vegetabilisk olja endast i ekonomisk hållbarhet, medan i andra aspekter inklusive den övergripande aspekten är vegetabilisk olja mer hållbar än mineralolja. Bland annat presterar mineralolja sämst i miljömässig hållbarhet, medan vegetabilisk olja har ekonomisk hållbarhet. Dessutom förväntas det utformade ramverket användas för att utvärdera hela livscykeln för en produkt och kan hänvisas till i framtida förbättringar av försörjningskedjan, eftersom fler index kan utvecklas baserat på matematikens luddiga talberäkningsprincip.

[pt] A programação de produção em refinaria pode ser compreendida como decisões que buscam otimizar alocação de recursos, o sequenciamento de atividades e a sua realização temporal, respeitando restrições e visando ao atendimento de múltiplos objetivos. Apesar da complexidade e natureza combinatória, a atividade carece de sistemas sofisticados que auxiliem o processo decisório, especialmente baseadas em otimização, pois as ferramentas utilizadas são planilhas ou softwares de simulação. A diversidade de objetivos do problema não implica em equivalência de importância. Pode-se considerar que existem grupos, onde os que afetam diretamente a capacidade produtiva da refinaria se sobrepõem aos associados à maior continuidade operacional. Esta tese propõe o desenvolvimento de algoritmos multiobjetivos para programação de petróleo em refinaria. As propostas se baseiam em conceituadas técnicas da literatura multiobjetivo, como dominância de Pareto e decomposição do problema, integradas à programação genética com inspiração quântica. São estudados modelos em um ou dois níveis de decisão. A diferenciação dos grupos de objetivos é avaliada com base em critérios estabelecidos para considerar uma solução proposta como aceitável e também é avaliada a influência de uma população externa no processo evolutivo. Os modelos são testados em cenários de uma refinaria real e os resultados são comparados com um modelo que trata os objetivos de forma hierarquizada. As abordagens baseadas em dominância e em decomposição apresentam vantagem sobre o algoritmo hierarquizado, e a decomposição é superior. Numa comparação com o modelo em dois níveis de decisão, apenas o que utiliza estratégia de decomposição em cada nível apresenta bons resultados. Ao final deste trabalho é obtido mais de um modelo multiobjetivo capaz de oferecer um conjunto de soluções que atendam aos objetivos críticos e deem flexibilidade de análise a posteriori para o programador de produção, o que, por exemplo, permite que ele pondere questões não mapeadas no modelo. / [en] Refinery scheduling can be understood as a set of decisions which aims to optimize resource allocation, task sequencing, and their time-related execution, respecting constraints and targeting multiple objectives. Despite its complexity and combinatorial nature, the refinery scheduling lacks more sophisticated support decision tools. The main systems in the area are worksheets and, sometimes, simulation software. The multiple objectives do not mean they have the same importance. Actually, they can be grouped whereas the objectives related to the refinery production capacity are more important than the ones related to a smooth operation. This thesis proposes the development of multiobjective algorithms applied to crude oil refinery scheduling. The proposals are based on the major technics of multiobjective literature, like Pareto dominance and problem decomposition, integrated with a quantum-inspired genetic programming approach. One and two decision level models are studied. The difference between groups is handled with conditions that define what can be considered a good solution. The effect of using an archive population in the evolutionary process is also evaluated. The results of the proposed models are compared with another model that handles the objectives in a hierarchical logical. Both decomposition and dominance approaches have better results than the hierarchical model. The decomposition model is even better. The bilevel decomposition method is the only one, among two decision levels models, which have shown good performance. In the end, this work achieves more than one multiobjective model able to offer a set of solutions which comprises the critical objectives and can give flexibility to the production scheduler does his analysis. Therefore, he can consider aspects not included in the model, like the forecast of crude oil batches not scheduled yet.