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

The Occurrence and Fate of Steroid Hormones from Manure Amended Agriculture Fields

Sosienski, Theresa Ann 14 July 2017 (has links)
Hormones are endocrine disrupting compounds, which have been shown to alter the sexual development of aquatic organisms. Animal manure applications to agricultural fields for nutrient management can be a source of environmental hormones. This dissertation investigates the occurrence of hormones in fields applied with various manures and their adjacent streams, as well as the effect of manure application technologies on the fate of hormones in soils, sediments, and runoff. A total of 11 hormone compounds were studied. All studied analytes were quantified using liquid chromatography and triple-quadrupole mass spectrometry following various sample extraction and clean-up strategies. The spatial and temporal distribution of manure-associated hormones in a manure surface applied agricultural field and adjacent stream was studied at time points up to 7.5 months after a routine manure application. Hormones were detected mainly in the top 0-5cm soils. Significantly higher levels of hormones were found in the drystack applied area of the field when compared to dairy manure slurry applied portion. New technologies for the subsurface application of poultry litter show promise as a tool to reduce the transportation of environmental hormones in surface runoff. Once adequate sampling protocols were established; it was determined that subsurface injection of both dairy manure and poultry litter reduced the impact of manure surface runoff. Hormones also showed little vertical and lateral movement in the soil. The transformation rates of 1,4-androstadiene-3,17-dione, 4-androstene-3,17-dione and estrone were studied comparing the effects of temperature, soil type, and application type. The calculated half-life of 1,4-androstadiene-3,17-dione in poultry litter surface-applied soils was 1.9 times higher than that in the poultry litter subsurface-injected soils, indicating a faster dissipation rate in the injection slits. Estrone persisted at detectable levels for the duration of the study in all treatments. The continued use of best management practices and innovative manure management techniques for the reduction of nutrients, sediment and other contaminants has the potential to also reduce hormone transport to the natural environment. Monitoring many different types of hormones in all areas of an environmental system will continue to provide better information on the occurrence and fate of hormones sourced from manure amended soils. / Ph. D.
32

Balanço e eficiência de uso de nutrientes em sistemas de produção de grãos na região Oeste do Paraná / Balance and nutrient use efficiency in grain production systems in western Paraná

Madalosso, Tiago 26 August 2015 (has links)
Made available in DSpace on 2017-07-10T17:37:11Z (GMT). No. of bitstreams: 1 Tiago_Madalosso.pdf: 2572164 bytes, checksum: 04f38c061e9c675c1dc4b7c079f8fa9f (MD5) Previous issue date: 2015-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In Brazil it is possible for two or more per year grain crop cultivation, but there is evidence that the cultivation tillage system with only commercial crops has resulted in soil degradation. The objective of this study was to evaluate the balance and efficiency of use of N, P and K, the effect on the chemical properties of soil and biometric variables of crops in grain production systems in western Parana region, encompassing different fertilization and probate cultures. The experiment was designed in randomized blocks with the treatments arrangement in divided plots with 4 repetitions. In the plots were installed the winter successions (5), wheat, oats, sunn hemp, corn second crop + brachiaria and corn 2nd harvest and the subplots fertilizers (3) organic, organomineral and mineral. The summer crop was planted to soybeans. The test was conducted for three seasons, starting with the planting of soybeans in 2013. Soil samples were collected after the 3rd growing at 0-10 and 10-20 cm. In the first crop, the use of organic fertilizer promoted increase in grain yield, mass of thousand grains, at the height of soybean plants, the bedding, the number of pods per plant, increased the leaf content and export of N by grain soybeans. In the third crop, there were no differences between the fertilizer and succession to black oat and sun hemp provided higher-yielding soybeans. The oat presented the highest dry matter yield, higher concentration of P in the shoot and greater extraction of N, P and K. Corn consortium + brachiaria reduced the yield of maize grain compared to monocrop. The application of poultry litter and the use of oat or crotalária as cover crops in winter, provide increased grain yield for the soybean crop. Using the same dose of P and K there is no difference in the yield of soybeans, corn and wheat between mineral fertilizers and organomineral. A use of poultry litter promotes increase of soil P and K soil, but does not increase the levels organic matter. P and K use efficiency is higher in soy succession - 2 nd harvest corn. The efficiency of use of N, P and K is lower in the fertilizer with organic fertilizer. There is no difference in the use efficiency of P and K between organomineral and mineral fertilizers, as for N, the mineral fertilizer has higher efficiency. ON was the nutrient with the most negative balance in the soil and the use of cover crops (black oats and crotalaria) increases the N balance in the soil. OP showed balance in the soil near zero being lower in succession with wheat and oats. The K balance in the soil was negative and was not different between the tested grain and fertilizer production systems / No Brasil é possível o cultivo de duas ou mais safras de grãos por ano, porém há evidências de que o cultivo em sistema plantio direto apenas com culturas comerciais tem resultado na degradação do solo. O objetivo deste trabalho foi avaliar o balanço e eficiência de utilização de N, P e K, o efeito sobre as propriedades químicas do solo e variáveis biométricas das culturas em sistemas de produção de grãos na região oeste do Paraná, englobando diferentes adubações e sucessões de culturas. O experimento foi delineado em blocos ao acaso com arranjo dos tratamentos em parcelas divididas, com quatro repetições. Nas parcelas foram instaladas as sucessões de inverno (5), trigo, aveia preta, crotalária, milho 2a safra + braquiária e milho 2a safra e nas subparcelas os fertilizantes (3), orgânico, organomineral e mineral. A safra de verão foi cultivada com soja. O ensaio foi conduzido por três safras, iniciando com a semeadura da soja em 2013. As amostras de solo foram coletadas após o 3° cultivo nas profundidades de 0-10 e 10-20 cm. No primeiro cultivo, a utilização de fertilizante orgânico promoveu incremento no rendimento de grãos, na massa de mil grãos, na altura de plantas de soja, no acamamento, no número de vagens por planta, incrementou o teor foliar e exportação de N pelos grãos de soja. No terceiro cultivo, não houve diferenças entre os fertilizantes e as sucessões com aveia preta e crotalária proporcionaram maior rendimento de grãos de soja. A aveia preta apresentou a maior produção de massa seca, maior concentração de P na parte aérea e maior extração de N, P e K. O consórcio de milho + braquiária reduziu o rendimento de grãos de milho quando comparado ao cultivo solteiro. A aplicação de cama de frango e a utilização de aveia preta ou crotalária como planta de cobertura no inverno, proporcionam maior rendimento de grãos para a cultura da soja. Utilizando a mesma dose de P e K não há diferenças no rendimento de grãos de soja, milho e trigo entre os fertilizantes mineral e organomineral. A utilização de cama de frango promove incremento dos teores de P e K do solo, porém não incrementa os teores de matéria orgânica. A eficiência de uso de P e K é superior na sucessão soja - milho 2ª safra. A eficiência de uso de N, P e K é inferior na adubação com fertilizante orgânico. Não há diferença na eficiência de uso de P e K entre os fertilizantes organomineral e mineral, já para o N, o fertilizante mineral apresenta eficiência superior. O N foi o nutriente com o balanço no solo mais negativo e a utilização de plantas de cobertura (aveia preta e crotalária) incrementa o balanço de N no solo. O P apresentou balanço no solo próximo a zero sendo menor nas sucessões com trigo e aveia preta. O balanço de K no solo foi negativo e não foi diferente entre os sistemas de produção de grãos e fertilizantes testados
33

Geração de biogás utilizando cama de aviário e manipueira / Biogas Generation Using poultry litter bed and Cassava Water

Suzuki, Ana Beatryz Prenzier 10 February 2012 (has links)
Made available in DSpace on 2017-07-10T15:14:47Z (GMT). No. of bitstreams: 1 Ana Beatriz.pdf: 636763 bytes, checksum: 45817df88d891cdcadcfe39bc37b67ea (MD5) Previous issue date: 2012-02-10 / The demand for energy have been shown to be increasing and to meet this demand is necessary to seek alternative sources of energy. This study aimed to verify the biogas production by mixing the poultry litter with cassava wastewater for obtaining and analyzing their biogas effluent and checking the reduction of organic load. Thus trying to solve the environmental issue of the disposal thereof and producing clean, renewable energy contributing to the Brazilian energy matrix. There were used batch digesters made of vinyl and fed with different mixtures of biomass and thus verified the amount of biogas generated and the biogas quality obtained. We found significant biogas productions of up to 0.39 and 0.30 L d-1 and load reductions which reached 81.94% / A procura por energia têm se mostrado cada vez maior e para suprir essa demanda é necessário buscar fontes alternativas de energia. O presente trabalho teve como objetivo verificar a produção de biogás através da mistura da cama de aviário com manipuiera para obtenção de biogás e analisando seus efluentes e verificando a redução de carga orgânica. Tentando assim resolver a questão ambiental da destinação dos mesmos e produzindo energia limpa e renovável contribuindo para a matriz energética brasileira. Foram utilizados biodigestores do tipo batelada feitos com PVC e alimentados com diferentes misturas da biomassa podendo assim verificar a quantidade de biogás gerado e a qualidade do biogás obtido. Foram encontradas Produções de biogás significativas de até 0,39 e 0,30 L d-1 e reduções de carga que chegaram a 81,94%.
34

TWO ESSAYS IN FERTILIZER MANAGEMENT FOR IMPROVED PROFITABILITY

Wade, Shelby Dawn 01 January 2019 (has links)
Corn production in the United States has become increasingly efficient over the years. The use of nitrogen fertilizers has played a substantial role in this efficiency. Nitrogen drives biomass production which leads to increased yields. Unlike other nutrients, nitrogen is more mobile making it easier to lose through leaching and volatilization. The first part of this analysis uses an econometric model to examine the relationship between nitrogen usage and weather data. This relationship leads to farm management decisions to reduce nitrogen fertilization expenses. In addition to the use of nitrogen fertilizers, farmers in Kentucky take advantage of an abundance of poultry litter as a fertilizer source. Traditional poultry litter fertilization methods are being challenged by new technology, sub-surface injection, which has the potential to increase corn yields as compared to other methods. The second part of this analysis uses a resource allocation linear programming model to determine the economic viability of the sub-surface injection method for both spring and fall fertilizer applications. This model also reveals both farm management implications and provides valuable information for the development and commercialization of the sub-surface injector.
35

Gesso agrícola melhora a qualidade fertilizante da cama de frango? / The gypsum fertilizer improves quality of poultry litter?

Silva, Janaina Matias Pereira da [UNESP] 29 February 2016 (has links)
Submitted by JANAINA MATIAS PEREIRA DA SILVA null (jana.mps@hotmail.com) on 2016-04-29T12:35:20Z No. of bitstreams: 1 Janaina DISSERTAÇÃO FINAL fev com ficha.pdf: 495368 bytes, checksum: 8f0f99954b0a3ecb942b32b395479d4b (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-05-02T18:00:20Z (GMT) No. of bitstreams: 1 silva_jmp_me_bot.pdf: 495368 bytes, checksum: 8f0f99954b0a3ecb942b32b395479d4b (MD5) / Made available in DSpace on 2016-05-02T18:00:20Z (GMT). No. of bitstreams: 1 silva_jmp_me_bot.pdf: 495368 bytes, checksum: 8f0f99954b0a3ecb942b32b395479d4b (MD5) Previous issue date: 2016-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A cama de frango é um adubo orgânico cuja principal característica é a concentração de nitrogênio, porém, há uma alta taxa de volatilização de nitrogênio em forma de amônia. No presente estudo, foi possível avaliar a eficiência do gesso agrícola em diminuir as perdas de nitrogênio da cama de frango por volatilização e melhorar sua característica como fertilizante na adubação da cultura do milho. Os ensaios constituíram pela aplicação de gesso agrícola em cama de frangos de corte nos quais, foram empregados doses de 15%, 30% e 45% em relação ao volume de maravalha, e um tratamento controle sem adição de gesso. Durante todo o período de cria, nos três lotes consecutivos de frangos, foram coletadas amostras de amônia volatilizada por meio de sensor durante três períodos do dia a cada sete dias. Uma amostragem da cama foi coletada ao final de cada ciclo para análises químicas. Ao término da cria a cama foi retirada do galpão e aplicada como fertilizante em vasos para o cultivo do milho em casa de vegetação, mantendo os tratamentos inicias combinados com e sem a aplicação de 100mg de nitrogênio/kg da massa de solo, formando um esquema fatorial de quatro tratamentos com duas variáveis (4x2). Após 50 dias de cultivo foram coletadas amostras de solo para análises, observou-se que o gesso foi incapaz de controlar a volatilização de amônia, não diferindo nos teores de nitrogênio inorgânico. Portanto, os tratamentos não incrementaram eficiência em produção de matéria seca do milho, outrora, essas combinações entre cama de frango, gesso e nitrogênio, elevaram a concentração de fósforo e nitrogênio na raiz da cultura. / Poultry litter is organic fertilizer whose major characteristic is the nitrogen concentration, but, there is a high volatization nitrogen rate in the form ammonia. This study, was possible appreciate the phosphorgypsum efficiency to reduce nitrogen losses on poultry litter through volatilization and upgrade characteristic like a fertilizer in the cultivation corn. The testing considered in application phosphogypsum in poultry litter, were employed 15%, 30% and 45% doses compared to wood shaving volume, and control treatment without addition gypsum. While the period creates, three consecutive poultry lots, was collected samples volatilized ammonia by a sensor during three periods in the day each seven days. Was collected sampling bed in every final cycle to chemical analysis, finishing all cycle the bed was removed to be applied as fertilizer inside vase corn cultivation in house vegetation, keeping the treatments initial combination with and without application 100mg nitrogen / kg soil volume, constituted a factorial arrangement of four treatments with two variables (4x2). After 50 days cultivation was collected samples soil to analyze, it was observed that gypsum is unable to control ammonia volatization, not differing inorganic nitrogen. Therefore, treatments was not increase efficiency in production corn dry matter, in the other hand, this combinations between poultry litter, gypsum and nitrogen increased the concentration phosphorus and nitrogen in cultivation root.
36

Influence of a Biodegradable Litter Amendment on the Pyrolysis of Poultry Litter

Tarrant, Ryan Carl Allen 02 November 2010 (has links)
The effects of adding a biodegradable litter amendment (AmmoSoak), developed from steam exploded corncobs, to poultry litter prior to pyrolysis on the product yields and qualities were investigated. Mixtures of litter and AmmoSoak were pyrolyzed in a bench-scale fluidized bed reactor. The objective of the second phase was to start-up a pilot-scale fluidized bed reactor unit. The poultry litter had a lower higher heating value (HHV), higher moisture, ash, nitrogen, sulfur, and chlorine contents than AmmoSoak. Analysis of the poultry litter indicated a mixture of volatiles, hemicelluloses, cellulose, lignin, ash, and proteins. AmmoSoak had a simpler composition than the litter; mainly hemicelluloses, cellulose, and lignin. Bench-scale studies indicated that adding AmmoSoak affected the yields and characteristics of the products. Addition of Ammosoak increased the bio-oil and syngas yields and decreased char yields. Adding AmmoSoak to the feed decreased the pH, water contents, initial viscosity, and the rate at which the viscosity increased with time, while densities and HHVs increased. The addition of Ammosoak to poultry litter also increased the carbon and oxygen contents of the boi-oils while nitrogen, hydrogen, sulfur, chlorine and ash contents decreased. A pilot-scale fluidized bed reactor was designed, constructed, installed and investigated for the pyrolysis of poultry litter. Fluidization and thermal equilibrium of the reactor were successfully demonstrated. The reactor was heated by combustion of propane. To ensure complete combustion, the combustion water was collected and compared to the stoichiometric yield. Complete combustion was achieved. Bio-oil yields on the pilot scale were lower than those obtained on the bench-scale pyrolysis unit. The water soluble fractions of the bio-oils were rich in oxygen. Water insoluble fractions were rich in carbon and ash. / Master of Science
37

Aproveitamento de cinzas da queima de resíduos agroindustriais na produção de compósitos fibrosos e concreto leve para a construção rural / Use of agro industrials ashes the burning of waste in the production of fiber composite and lightweight concrete for rural construction

Kawabata, Celso Yoji 06 March 2008 (has links)
O presente trabalho teve como objetivo estudar a viabilidade da utilização de cinzas de resíduos agroindustriais (bagaço de cana-de-açúcar, cama de frango e casca de arroz) como aditivos minerais substitutos ao cimento Portland, na produção de compósitos fibrosos e concreto leve. As cinzas foram obtidas através da queima e moagem controlada dos resíduos, e tiveram suas características químicas e físicas analisadas. Além do \"compósito referência\" (0% de substituição), os compósitos fibrosos foram produzidos com teores de substituição de cimento Portland de 10%, 15% e 20%, e os concretos leves foram produzidos com 10% de substituição. Foram realizados ensaios físicos e mecânicos nos compósitos fibrosos e concreto leve. Os resultados mostraram que as cinzas de casca de arroz apresentaram propriedades pozolânicas e que podem ser empregadas para a produção dos compósitos fibrosos e concretos leve. No estudo com compósitos fibrosos, os resultados físicos e mecânicos em sua maioria indicaram que a cinza de casca de arroz apresentou os melhores resultados. Como não apresentaram propriedades pozolânicas, as cinzas de bagaço de cana-de-açúcar e cama de frango, mesmo apresentando bons resultados, podem ser utilizadas como \"micro-fillers\". No estudo com concreto leve, a cinza de casca de arroz também se apresentou como melhor substituto para o cimento Portland por apresentar os melhores resultados nos ensaios realizados. / This research examines the viability of the use of waste agro industrials ashes (sugar cane bagasse, poultry litter and rice husk) and mineral additives substitutes to Portland cement in the production of composite fiber and lightweight concrete. The ashes were obtained through controlled burns and milling waste, and had their chemical and physical characteristics analyzed. Besides the \"composite reference\" (0% substitution), the fiber composites were produced with levels of replacement of Portland cement, 10%, 15% and 20%, and lightweight concrete were produced with 10% of replacement. Were tested on physical and mechanical fiber composites and lightweight concrete. The results showed that the ashes of rice husk had pozolanic properties and can be used for the production of fiber composite and lightweight concrete. In the study with fiber composites, the results physical and mechanical mostly indicated that the rice husk ash showed the best results. As there had pozolanics properties, the ashes of sugar cane bagasse and poultry litter, even showing good results, can be used as \"micro-fillers\". In the study with lightweight concrete, the ash of rice husk is also presented as a better replacement for Portland cement by presenting the best results in tests.
38

Avaliação do uso glicerina em dietas para frangos de corte nas fases pré-inicial e final / Evaluation of the use glycerin in diets for broilers in the pre-starter and final phases

Freitas, Leonardo Willian de 01 February 2013 (has links)
Dois experimentos foram conduzidos com o objetivo de avaliar a utilização de dietas com níveis crescentes de glicerina de biodiesel apenas na fase pré-inicial (1 a 7 dias) e apenas na fase final (35 a 42 dias de idade) de frangos de corte, respectivamente. As variáveis analisadas incluíram o desempenho, o rendimento de carcaça e cortes, a retenção de umidade em pintos aos 7 dias, a umidade de cama, a incidência de pododermatite, os níveis plasmáticos de colesterol e triglicerídeos e o custo da ração referente ao ganho de peso. Os tratamentos consistiram de dietas formuladas com 0%, 5% ou 10% de glicerina, sendo isonutritivas e formuladas à base de milho, farelo de soja e óleo de milho. A glicerina usada continha 83,6% de glicerol, 11,2% de água, 1,83% de sódio e 397 mg/kg de metanol, com energia metabolizável estimada de 3258 kcal/kg. No Experimento I, as dietas com glicerina foram fornecidas apenas na fase pré-inicial ou durante todo o ciclo de criação com 1610 aves em um delineamento inteiramente casualizado com 5 tratamentos e 7 repetições. Na primeira semana, as dietas com glicerina promoveram melhora significativa no ganho de peso e na conversão alimentar, sem afetar o consumo de ração e viabilidade. Essa melhora não foi mantida após os 14 dias de idade. Não houve efeito de tratamentos sobre o ganho de peso, consumo de ração e conversão alimentar. Entretanto, houve redução significativa na viabilidade aos 35 dias de idade das aves com 10% de glicerina por todo ciclo, mas não aos 42 dias; ao final do experimento, o índice de eficiência produtiva desse tratamento sofreu redução significativa. A umidade da cama das aves do tratamento com 10% de glicerina por todo ciclo de criação foi mais alta que dos demais a partir dos 21 dias, entretanto a incidência de pododermatite foi mais severa tanto para 5% como para 10% de glicerina por todo ciclo. Os níveis e tempos de fornecimento de glicerina não afetaram o rendimento de carcaça e de cortes ou a gordura abdominal. No experimento II, as dietas experimentais foram fornecidas a 819 frangos apenas na semana final de criação em um experimento inteiramente casualizado com 3 tratamentos e 7 repetições. O desempenho e o custo de ração por kg de ganho de peso não foram afetados pelos tratamentos. Nos Experimentos I e II, as rações contendo glicerina durante todo o ciclo ou apenas na última semana não resultaram em alteração nas concentrações plasmáticas de triglicerídeos e colesterol dos frangos. Dietas contendo 5% ou 10% de glicerina na fase pré-inicial ou 5% de glicerina continuamente não afetam a produtividade de frangos de corte, enquanto o nível de 10% durante todo o ciclo foi prejudicial. Esse mesmo nível de glicerina pode ser usado na dieta dos 35 aos 42 dias de idade sem afetar as aves. / Two experiments were conducted to evaluate the use of diets with increasing levels of biodiesel glycerin only in pre-starter (1-7 days) and only in the final phase (35-42 days of age) of broilers, respectively. The variables analyzed included the performance, carcass and parts yield, moisture retention in chicks at 7 days, litter moisture, incidence of foot pad dermatitis, plasma levels of cholesterol and triglycerides and diet cost related to weight gain. Treatments were isonutritive diets based on corn, soybean meal and corn oil containing 0, 5 and 10% glycerin. The glycerin used contained 83.6% glycerol, 11.2% water, 1.83% sodium and 397 mg/kg methanol, with estimated metabolizable energy value of 3,258 kcal/kg. In the first experiment, diets with glycerin were provided only in the pre-starter or for the entire growth period with 1610 birds in a completely randomized design with 5 treatments and 7 replications. In the first week, diets with glycerin resulted in significant improvement in weight gain and feed conversion without affecting feed intake and viability. This improvement was not sustained after 14 days of age. There was no effect of treatments on weight gain, feed intake and feed conversion. However, there was a significant reduction in viability at 35 days of age for the birds with 10% glycerin throughout the cycle, but not at 42 days; at the end of the experiment, the productivity index of this treatment was significantly decreased. Litter moisture for the treatment with 10% glycerin throughout the cycle was higher than the for the others from the 21 days, however the incidence of foot pad dermatitis was more severe for both 5% and 10% glycerin treatments for the entire period. The levels and periods of glycerin feeding did not affect carcass and parts yield and abdominal fat. In experiment II, the experimental diets were provided to 819 chickens only in the final week of growth in a completely randomized design with 3 treatments and 7 replications. The performance and feed cost per kg of weight gain were not affected by treatments. In Experiments I and II, the diets containing glycerin throughout the cycle or just in the last week resulted in no change in plasma concentrations of triglycerides and cholesterol of chickens. Diets containing 5% or 10% glycerin in the pre-starter phase or 5% glycerin continually did not affect the productivity of broilers, while the 10% level throughout the cycle was detrimental. This same level of glycerin can be used in the diet from 35 to 42 days without affecting the birds.
39

Transformation of veterinary ionophore antibiotics under conditions related to water-soil-litter systems

Sun, Peizhe 22 May 2014 (has links)
Veterinary pharmaceuticals are routinely used in livestock production to treat diseases, prevent infections, and promote growth. However, the potential release of pharmaceuticals from agricultural activities has raised concerns because they may pose detrimental effects to the ecosystems and human health, for example fostering the evolution of antibiotic-resistant bacteria in the natural environment. A better understanding of the environmental fate of veterinary pharmaceuticals is critical to properly assess and mitigate their risks. This dissertation focuses on a major group of veterinary pharmaceuticals, ionophore antibiotics (IPAs), which is sold at over 4 million kilograms per year and constitutes more than one third of the total antibiotic consumption by the livestock industry in the U.S. Despite the extensive usage of IPAs, their environmental fate was not well-understood. Therefore, this study aimed at achieving a comprehensive understanding of the occurrence, persistence, and transformation of IPAs from poultry litter before and after applications to the agricultural lands. Three of the most commonly used members of IPAs were investigated in this study: monensin (MON), salinomycin (SAL), and narasin (NAR). Based on the common management practices of poultry litter, the potential abiotic and biotic transformation reactions of IPAs were examined under varying conditions relevant to the water-soil-litter systems. This dissertation consists of three sections. First, a robust analytical method was developed to quantify IPAs in various environmental compartments, especially in high organic-containing matrices such as poultry litter, and soil and runoff from litter-fertilized lands. Efforts were made to optimize the analytical method with respect to improving extraction recovery, reducing matrix effects, and validating a surrogate standard. Second, lab-scale experiments were set up to determine the chemical properties of IPAs in aqueous environments and to study the abiotic transformation of IPAs, including hydrolysis and photolysis. The results showed that IPAs are prone to hydrolytic transformation in acidic environments, which are likely to be encountered in acidic soils, alum-amended litter (alum: Al₂(SO₄)₃•12H₂O), and acidic runoff. Multiple transformation pathways were proposed based on the identified hydrolysis products. It is also noteworthy that the hydrolysis products of MON still exhibited a toxic effect on the selected microorganism (Bacillus subtilis). SAL and NAR were found to undergo direct photolysis under both UV light and sunlight irradiation. In natural water matrix, IPAs were also degraded by indirect photolysis with hydroxyl radicals generated by light-excited nitrate. Dissolved organic matter can shield IPAs from light and slow down their photolysis. Third, the biodegradation potential of IPAs was first tested in litter and soil microcosms. Factor analysis was conducted to delineate the interaction of water and temperature on IPA degradation in the litter. Litter-fertilized and non-fertilized soil microcosms were compared on the degradation of MON and SAL. Furthermore, the inhibition and biotransformation potential of IPAs were assessed under different redox conditions with litter-enriched cultures. Inhibition tests focused on examining IPAs’ impact on microbial community functions, including denitrification, sulfate-reduction, and methane production. Biodegradation tests were conducted with different electron acceptors, including oxygen, nitrate, sulfate, and organic carbons, with efforts to elucidate primary biotransformation products. On the basis of the results obtained in this study, several recommendations on litter management and IPA selection were made to help mitigate the release and transport of IPAs, as well as enhance their degradation. Overall, this study significantly improved the understanding of the environmental fate of IPAs and the obtained knowledge can aid proper selection of IPAs and management strategies in future applications to minimize the risks of antibiotic micropollutants in the environment.
40

Avaliação do uso glicerina em dietas para frangos de corte nas fases pré-inicial e final / Evaluation of the use glycerin in diets for broilers in the pre-starter and final phases

Leonardo Willian de Freitas 01 February 2013 (has links)
Dois experimentos foram conduzidos com o objetivo de avaliar a utilização de dietas com níveis crescentes de glicerina de biodiesel apenas na fase pré-inicial (1 a 7 dias) e apenas na fase final (35 a 42 dias de idade) de frangos de corte, respectivamente. As variáveis analisadas incluíram o desempenho, o rendimento de carcaça e cortes, a retenção de umidade em pintos aos 7 dias, a umidade de cama, a incidência de pododermatite, os níveis plasmáticos de colesterol e triglicerídeos e o custo da ração referente ao ganho de peso. Os tratamentos consistiram de dietas formuladas com 0%, 5% ou 10% de glicerina, sendo isonutritivas e formuladas à base de milho, farelo de soja e óleo de milho. A glicerina usada continha 83,6% de glicerol, 11,2% de água, 1,83% de sódio e 397 mg/kg de metanol, com energia metabolizável estimada de 3258 kcal/kg. No Experimento I, as dietas com glicerina foram fornecidas apenas na fase pré-inicial ou durante todo o ciclo de criação com 1610 aves em um delineamento inteiramente casualizado com 5 tratamentos e 7 repetições. Na primeira semana, as dietas com glicerina promoveram melhora significativa no ganho de peso e na conversão alimentar, sem afetar o consumo de ração e viabilidade. Essa melhora não foi mantida após os 14 dias de idade. Não houve efeito de tratamentos sobre o ganho de peso, consumo de ração e conversão alimentar. Entretanto, houve redução significativa na viabilidade aos 35 dias de idade das aves com 10% de glicerina por todo ciclo, mas não aos 42 dias; ao final do experimento, o índice de eficiência produtiva desse tratamento sofreu redução significativa. A umidade da cama das aves do tratamento com 10% de glicerina por todo ciclo de criação foi mais alta que dos demais a partir dos 21 dias, entretanto a incidência de pododermatite foi mais severa tanto para 5% como para 10% de glicerina por todo ciclo. Os níveis e tempos de fornecimento de glicerina não afetaram o rendimento de carcaça e de cortes ou a gordura abdominal. No experimento II, as dietas experimentais foram fornecidas a 819 frangos apenas na semana final de criação em um experimento inteiramente casualizado com 3 tratamentos e 7 repetições. O desempenho e o custo de ração por kg de ganho de peso não foram afetados pelos tratamentos. Nos Experimentos I e II, as rações contendo glicerina durante todo o ciclo ou apenas na última semana não resultaram em alteração nas concentrações plasmáticas de triglicerídeos e colesterol dos frangos. Dietas contendo 5% ou 10% de glicerina na fase pré-inicial ou 5% de glicerina continuamente não afetam a produtividade de frangos de corte, enquanto o nível de 10% durante todo o ciclo foi prejudicial. Esse mesmo nível de glicerina pode ser usado na dieta dos 35 aos 42 dias de idade sem afetar as aves. / Two experiments were conducted to evaluate the use of diets with increasing levels of biodiesel glycerin only in pre-starter (1-7 days) and only in the final phase (35-42 days of age) of broilers, respectively. The variables analyzed included the performance, carcass and parts yield, moisture retention in chicks at 7 days, litter moisture, incidence of foot pad dermatitis, plasma levels of cholesterol and triglycerides and diet cost related to weight gain. Treatments were isonutritive diets based on corn, soybean meal and corn oil containing 0, 5 and 10% glycerin. The glycerin used contained 83.6% glycerol, 11.2% water, 1.83% sodium and 397 mg/kg methanol, with estimated metabolizable energy value of 3,258 kcal/kg. In the first experiment, diets with glycerin were provided only in the pre-starter or for the entire growth period with 1610 birds in a completely randomized design with 5 treatments and 7 replications. In the first week, diets with glycerin resulted in significant improvement in weight gain and feed conversion without affecting feed intake and viability. This improvement was not sustained after 14 days of age. There was no effect of treatments on weight gain, feed intake and feed conversion. However, there was a significant reduction in viability at 35 days of age for the birds with 10% glycerin throughout the cycle, but not at 42 days; at the end of the experiment, the productivity index of this treatment was significantly decreased. Litter moisture for the treatment with 10% glycerin throughout the cycle was higher than the for the others from the 21 days, however the incidence of foot pad dermatitis was more severe for both 5% and 10% glycerin treatments for the entire period. The levels and periods of glycerin feeding did not affect carcass and parts yield and abdominal fat. In experiment II, the experimental diets were provided to 819 chickens only in the final week of growth in a completely randomized design with 3 treatments and 7 replications. The performance and feed cost per kg of weight gain were not affected by treatments. In Experiments I and II, the diets containing glycerin throughout the cycle or just in the last week resulted in no change in plasma concentrations of triglycerides and cholesterol of chickens. Diets containing 5% or 10% glycerin in the pre-starter phase or 5% glycerin continually did not affect the productivity of broilers, while the 10% level throughout the cycle was detrimental. This same level of glycerin can be used in the diet from 35 to 42 days without affecting the birds.

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