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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.
161

Efeito do urucum (Bixa Orellana) na alteração de características de ovos de galinhas poedeiras / Effect of anatto (Bixa orellana) in alteration of caracteristics of poultry laying eggs

Harder, Marcia Nalesso Costa 11 November 2005 (has links)
Os ovos são alimentos de alto valor nutricional, já que possuem todas as vitaminas, aminoácidos e minerais essenciais. Os consumidores dão preferência, ovos com gema bem pigmentadas. A cultura popular trata o urucum como um poderoso agente anticolesterolemico, além de ser amplamente utilizado na forma de pigmento para a indústria. O presente trabalho avaliou os efeitos da adição de urucum (Bixa orellana L.) na ração de galinhas, verificando possível interferência na qualidade dos ovos, alteração de colesterol e cor e nas gemas e teores de vitamina A e ferro, inclusive com relação ao tempo. Para a obtenção das amostras foram utilizados 125 animais divididos em quatro tratamentos com adição de urucum na ração (0,5% - T2; 1,0% - T3; 1,5% - T4 e 2,0% - T5) e 1 controle (0% - T1). Os animais foram separados aleatoriamente em cinco blocos de cinco animais, totalizando 25 animais por parcela. Os ovos após serem colhidos passaram por análise de qualidade e padronização: pesados, classificados pelo ovoscópio, análise gravimétrica, unidade Haugh, altura de albúmen e gema, espessura da casca, diâmetro e índice de gema. O colesterol foi medido por método colorimétrico e a alteração da cor da gema, foi medida em colorímetro. Foi utilizado Teste de Tukey em nível de 5% para comparação de médias, utilizando o software SAS. Com relação à análise de qualidade dos ovos, não apresentou diferença significativa entre os tratamentos. A unidade Haugh e o índice de gema apresentaram diferença que, não se deve à adição do urucum por não ser uma resposta linear. Com relação ao colesterol, os tratamentos T2 e T3 (0,5% e 1,0% respectivamente) não apresentaram diferença significativa entre si, porém todos os tratamentos se diferenciaram em relação ao controle, apresentando diminuição no nível de colesterol, com o aumento da porcentagem de urucum na ração. Ao longo do tempo, o colesterol, mesmo administrando-se urucum para os animais, apresentou aumento significativo. Em relação a cor, determinada através do colorímetro Minolta, foram encontrados os seguintes resultados: para L, T1 e T2 apresentaram os valores superiores e, T4 e T5 os mais baixos; para a*: T4 e T5 apresentaram os maiores valores, diferindo dos demais; para b*: T1 e T2 apresentaram os maiores valores diferindo dos demais. Foi calculado também o Croma (cor) e Hue-Angle (saturação da cor). Para carotenóides (&#946; e &#945; caroteno), T5 apresentou valores superiores aos demais, diferindo estatisticamente (p<0,05). Com relação ao ferro total, T5 apresentou valores superiores aos demais, além do ferro dialisável, que provavelmente pela presença do aumento de carotenóides, também apresentou-se superior. Assim, pode-se concluir que a utilização de urucum na ração de poedeiras é útil, pois não interfere na qualidade dos ovos, influi na redução do colesterol, promove a cor das amostras, aumento de carotenóides e conteúdo de ferro. / The poultry meat and eggs are foods of high nutritional value, because they have all vitamins, amino acids and essential minerals to constitute a life. The popular culture treats the anatto like a power agent anticholesterolemic, there to be amply utilized like color source amount in the kitchen whatever in poultry farmer industry like a pigment, cosiderated that national and foreigner consumers have preference eggs with yolk yellow-orange and chickens with skin pigmented well. This research evaluated the effects of addition of anatto (Bixa orellana L.) add in ration of laying hens, relating the possible interference of the anatto in egg quality, cholesterol color and level in the yolk and tenor of vitamin A and iron, including the relationship with the time. The samples were obtained from 125 animal divided in 4 treatments with adittion of anatto (0.5% - T2; 1.0% - T3; 1.5% - T4 and 2.0% - T5 of anatto added in the ration) and 1 control (0% - T1 of anatto). The animals were separated aleatoric in 5 blocks, each block with 5 animals, with total 25 animals by parcel. The eggs harvesters were submeted by analysis of quality and standardization: they were weighty, classified by the eggscopic, gravimetric analysis, Haugh unit, albumen and yolk height, thickness of the shell, diameter and index yolk; the cholesterol was measured by a color methodology and the alteration of the yolk color, was measured in colorimeter. The statistic analysis was maked employing the Turkey test, level 5%, to compair means, utilized the SAS program. About the eggs quality analysis, they don’t showed significative difference between the treatments. The Haugh unit and the yolk index showed difference but it was not relationed to anatto add in ration. About the cholesterol, it decreased with the addition of anatto, but it increase with the time, even administrating anatto for the animals, there’s a significative increase at the cholesterol level. The color determined by the colorimeter, is dividing in 3 parts the prism: L, a* e b*: to L, T1 e T2 (control and 0.5% respectively) presented lower levels and, T4 and T5 (1.5% e 2.0% respectively) the highest. To a*: only T4 and T5 (1.5% and 2.0% respectively) don’t have difference of all. To b*: T1 and T2 (control and 0.5% respectively) presented the minimum value difering of all. There was calculated either, Croma (color) and Hue-Angle (color saturation). About the carotenes (&#946; and &#945; carotene), T5 showed higher values of the other, disagree of the statistics. About the total iron, T5 showed higher to the others, besides of the dialysable iron, that probably because of the presence of the increase of carotenes, showed higher either. So, can conclude that the utilization of anatto in ration of laying hens is very interesting, because it doesn’t interfere in the eggs quality, flow into the cholesterol reduction and color of the samples and increase carotenes and iron.
162

Uso da zootecnia de precisão na avaliação do bem-estar bioclimático de aves poedeiras em diferentes sistemas de criação / Use of precision animal production on bioclimatic welfare evaluations of laying hens in different rearing systems

Sulivan Pereira Alves 12 February 2007 (has links)
O objetivo geral desta pesquisa foi avaliar o bem-estar de aves poedeiras em dois diferentes sistemas de criação (gaiola e cama) e a qualidade desses sistemas em relação aos aspectos comportamentais, fisiológicos e produtivos utilizando ferramentas da zootecnia de precisão. O experimento foi desenvolvido no Setor de Avicultura do Departamento de Zootecnia da Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP) em Piracicaba, SP. A pesquisa constou de cinco períodos experimentais de 28 dias cada. Foram utilizadas 64 poedeiras da linhagem Isabrown e 64 poedeiras da linhagem Hy-Line W-36 com 19 e 21 semanas de idade respectivamente. O regime de luz adotado foi de 16 horas claro e 8 horas de escuro. Foram estabelecidos 2 tratamentos, sendo Tratamento 1: criação em gaiolas convencionais; Tratamento 2: sistema de criação em cama. O delineamento experimental adotado foi o inteiramente casualizado, em esquema fatorial 2x2 (2 linhagens e 2 sistemas de criação) com 4 repetições cada. A pesquisa abordou diferentes parâmetros: análise bioclimática; análise fisiológica; análise do desempenho zootécnico; análise da qualidade dos ovos; análise dos comportamentos; análise das condições de empenamento e aplicação da lógica Fuzzy na avaliação dos dados. A avaliação térmica foi realizada mediante a análise dos dados de temperatura do ar seco, da temperatura de globo negro e da umidade relativa, utilizando os índices de Temperatura de Globo e Umidade (ITGU) e Entalpia Específica (H) (KJ/kg ar seco). A análise das condições meteorológicas mostrou que a maior parte dos períodos experimentais ocorreu em condições de conforto térmico para as aves. A avaliação do comportamento permitiu identificar atividades de preferência e atividades indicativas de estresse, possibilitando a determinação das necessidades ambientais importantes ao bem-estar das aves. A avaliação comportamental por meio de imagens de vídeo permitiu uma análise mais apurada, fornecendo um banco de dados mais confiável do que a observação direta. O sistema de criação em cama, quando devidamente projetado, pode ser compatível ao sistema de criação em gaiolas no que diz respeito ao desempenho zootécnico e à qualidade de ovos produzidos; além disso, mostrou estimular a realização dos comportamentos naturais das aves e dessa forma, maior adequação às exigências de bem-estar. Porém, a melhor condição de bem-estar do sistema de criação em cama não apresentou melhor resultado no desempenho produtivo. A aplicação da lógica Fuzzy na obtenção de parâmetros indicativos das condições de bem-estar das aves nos diferentes sistemas de criação forneceu um modelo de fácil interpretação, permitindo a integração dos parâmetros avaliados, tornando-se uma ferramenta importante na interpretação das condições de bem-estar das aves. / The objective of this study was to evaluate the welfare of laying hens in two different rearing systems (cages and floor) and the quality of these systems concerning with the behavioural, physiological and productive aspects, using tools of precision animal production. The trial was conducted for five experimental periods of 28 days each. Sixty four pullets of the laying strain Isabrown and 64 pullets of the laying strain Hy-Line W-36, with ages of 19 and 21 weeks, respectively, were used. The treatments consisted of a combination of two rearing systems (conventional cages system and floor system with litter) and the two layer strains in a completely randomized design, with a 2x2 factorial arrangement, and four replicates. Different evaluation parameters were studied including bioclimatical; physiological; productive performance; behavioural; egg quality; feathering conditions and application of Fuzzy logic in data evaluations. The thermal evaluation was carried by analysis of dry air and black globe temperature and relative humidity, using the indices Temperature of Globe and Humidity (ITGU) and Enthalpy (H) (KJ/kg dry air). The analysis of the meteorological conditions showed that most of the experimental periods occurred in conditions of thermal comfort for the birds. The evaluation of the bird&#39;s behaviour allowed identifying preference activities and those indicative of stress, making possible the determination of bird&#39;s environmental necessities, important to their welfare. The behavioral evaluation through video images allowed more refined analysis, supplying a more trustful data base than direct observations. The floor system, when properly projected, can be comparable to the cage system with respect to the productive performance and the egg quality; moreover, it was shown to stimulate the accomplishment of natural behaviours, thus providing greater adequacy to the welfare requirements. However, the improved welfare conditions resulting of the floor system did not produce better results in the productive performance. The application of Fuzzy logic in the attainment of indicative parameters of the conditions of laying hens welfare in different rearing systems supplied an easy model, allowing the integration of the evaluated parameters, becoming an important tool in the interpretation of welfare conditions.
163

Ecologia reprodutiva de Catharacta Lonnbergi na ilha Elefante, arquipélago das Shetlands do Sul - Antártica

Seibert, Suzana 20 July 2011 (has links)
Submitted by Mariana Dornelles Vargas (marianadv) on 2015-05-04T14:37:06Z No. of bitstreams: 1 ecologia_reprodutiva.pdf: 5894767 bytes, checksum: fbc8661025167b9eb4559c7b3bbbb661 (MD5) / Made available in DSpace on 2015-05-04T14:37:06Z (GMT). No. of bitstreams: 1 ecologia_reprodutiva.pdf: 5894767 bytes, checksum: fbc8661025167b9eb4559c7b3bbbb661 (MD5) Previous issue date: 2011 / Nenhuma / A variação nos padrões de larga escala, como o clima e a disponibilidade de recursos, podem influenciar a fenologia e o sucesso reprodutivo dos indivíduos. Em menor escala, características como qualidade do adulto, composição e localização dos ninhos são cruciais para o sucesso reprodutivo. O objetivo do estudo é descrever a fenologia e avaliar o sucesso reprodutivo de Skua Marrom na Ilha Elefante, Arquipélago das Shetlands do Sul, além de avaliar algumas características dos ninhos que podem influenciar a variação destes fatores. Os dados foram coletados em 2009/10 e 2010/11, em Stinker Point, Ilha Elefante, sendo monitorados periodicamente 37 e 40 pares reprodutivos, respectivamente. A cada visita foram registradas as datas de postura, de nascimento, o número de ovos e filhotes nos ninhos. A posição geográfica dos ninhos e das colônias de aves reprodutivas (recursos) foi registrada com receptor de GPS. As distâncias dos ninhos para os recursos e para o vizinho mais próximo (DVProx) foram calculadas no software Arcgis. A proporção dos componentes dos ninhos (musgos, líquens e rochas) foi obtida através do processamento das fotografias dos ninhos no software Envi. Nenhum padrão, que relacione estes componentes às datas de postura e ao sucesso reprodutivo, foi constatado. A postura dos ovos ocorreu, em média, na primeira quinzena de dezembro. O sucesso reprodutivo variou significativamente entre estações (χ2=20,25 P<0,001) e a probabilidade de sobrevivência dos filhotes em relação a data de postura dos ovos (Nagelkerke R²=0.137 P=0,01), sendo maior nos meses de dezembro, independente do período (Nagelkerke R²= 0.137 P= 0,01). Observou-se uma relação significativa entre o sucesso reprodutivo e a distância da colônia de Pygoscelis antarctica em 2009/10 (Nagelkerke R2=0,20 P=0,03) e em 2010/11 (Nagelkerke R²=0.177 P=0,02). A DVProx influenciou negativamente na sobrevivência dos filhotes (Nagelkerke R2=0,30 P=0,02). As distâncias dos recursos e DVProx não variaram em relação às datas de postura. A menor probabilidade de sobrevivência dos filhotes mais próximos aos recursos não corrobora com o descrito na literatura, porém, dois fatores observados podem justificar tal padrão: ninhos próximos aos recursos estão mais agregados, aumentando a competição e predação intraespecífica; e o acesso à informação social, observado através da diferença nas datas de postura, resulta na maior concentração de indivíduos nestes locais, e consequentemente em diferentes probabilidades de sobrevivência dos filhotes. / Large scale patterns, as climate and resources show time fluctuations, what can influence individuals phenology and reproductive success. On a smaller scale, factors like adult quality, nest composition and location are also important to reproductive success. We aim to describe and evaluate Brown Skua phenology and reproductive success at Elephant Island, South Shetlands, and to evaluate how some nests characteristics can influence those factors fluctuations. Data were collected at 2009/10 and 2010/11 reproductive seasons at Stinker Point, Elephant Island, where 37 and 40 reproductive pairs were monitored each season. Laying and hatching date, number of chicks and eggs were recorded each nest visit. Nests and other seabird colonies (resources) location were recorded using a handheld GPS receiver. Distances of the nests to resources and to the nearest neighbor (NND) were calculated by means of Arcgis software. Nest components proportion (mosses, lichens and rocks) were obtained through photo classification at Envi software. There is no pattern on egg laying date and reproductive success in relation to nest components. Mean egg laying date were at early December. Reproductive success differed between seasons (χ2=20,25 P<0,001) and chick survival probability varied according to laying order (Nagelkerke R²=0.137 P=0,01), being higher at December both seasons (Nagelkerke R²= 0.137 P= 0,01). Reproductive success was related to the distance from nests to Pygoscelis antarctica breeding colonies at 2009/10 (Nagelkerke R2=0,20 P=0,03) and 2010/11 (Nagelkerke R²=0.177 P=0,02). NND were negatively correlated to chick survival (Nagelkerke R2=0,30 P=0,02). Egg laying date did not differ according to NND neither according to nest distance from other seabirds breeding colonies. We found a lower chick survival probability at nests closer to recourses, what differ from what is described at literature, nevertheless, two factors observed could explain this pattern, which are: nests located near to resources are found to be densely distributed, what increases competition and conspecific predation; social information access, based on egg laying date, results on a higher nests concentration and consequently on different chick survival probabilities.
164

Parâmetros genéticos de características de produção e qualidade de ovos em linhagens nacionais de galinhas caipiras / Genetic parameters of egg production and egg quality in national free-range chickens

Bogdanski, Fátima Auler 02 July 2019 (has links)
A avicultura é uma das principais atividades agropecuárias no Brasil, no entanto apresenta grande dependência de material genético importado. Além disso, o crescente interesse por produtos avícolas oriundos de sistemas alternativos de criação, onde as aves são criadas fora das gaiolas, pode exigir animais mais adaptados a esse sistema de criação bem como ao clima tropical brasileiro. Desta forma, dois estudos foram desenvolvidos. No primeiro, o objetivo foi estimar os parâmetros genéticos para características de produção e qualidade dos ovos de oito linhagens de galinhas caipiras. Foram utilizadas as medidas de idade à primeira postura (IPP), produção total de ovos até a 45ª semana (PROD), peso do ovo (PO), altura do albúmen (AA), cor da gema (CG), unidades Haugh (HU), resistência da casca (RC), espessura da casca (EC), peso da gema (PG) e peso da casca (PC) de 2030 ovos, oriundos de 645 aves. Os componentes de variância foram obtidos por meio de um modelo misto animal, onde foram incluídos os efeitos fixos de grupo de contemporâneas, corredor da gaiola e linhagem da galinha e os efeitos genético aditivo, ambiente permanente e residual. As herdabilidades variaram de 0,03 a 0,33. As correlações genéticas entre PROD e as características de qualidade dos ovos foram negativas e variaram entre -0,42 e -0,05. Correlações genéticas altas e positivas, entre 0,36 e 0,69, foram estimadas entre as características de qualidade externa do ovo. No segundo estudo, o objetivo foi estimar os parâmetros genéticos para características de cor da casca do ovo, bem como as correlações genéticas e fenotípicas entre estas características e as características de produção e qualidade dos ovos avaliadas no primeiro estudo. Foram realizadas análises colorimétricas (coordenadas L*, a*, b*, do sistema de cor CIELab) de 1142 ovos oriundos de 597 aves. As herdabilidades estimadas para estas coordenadas variaram de 0,35 a 0,48 e as correlações genéticas entre elas foram altas. No geral, as correlações genéticas entre a cor da casca e as características de qualidade do ovo foram baixas, sugerindo que a cor da casca não influencia a qualidade interna e externa do ovo. / Poultry farming is one of the main agricultural activities in Brazil, but it is highly dependent on imported genetic material. Moreover, the growing interest in poultry products from cage-free systems may require animals better adapted to free- range systems and tropical climate. Regarding this subject, two studies were developed. The aim of the first one was to estimate genetic parameters for egg production and egg quality traits in eight alternative poultry lines. The traits of interest were age at first egg (AFE), total egg production up to the 45th week (PROD), egg weight (EW), albumen height (AH), yolk color (YC), Haugh units (HU), eggshell strength (ESS), eggshell thickness (EST), yolk weight (YW) and eggshell weight (ESW). Phenotypic records of 645 laying hens and 2030 eggs were used. Variance components were estimated from a mixed animal model, which included the fixed effects of contemporary groups, cage location and hen line, and the additive genetic, permanent environmental and residual effects. Heritabilities ranged from 0.03 to 0.33. Genetic correlations between PROD and egg quality traits were negative and varied between -0.42 and -0.05. High and positive genetic correlations were estimated between eggshell quality traits. In the second study, the aim was to estimate genetic parameters for eggshell color and also genetic and phenotypic correlations between eggshell color and egg quality traits which were evaluated in the first study. Color coordinates from CIELab color space L* (brightness), a* (red/green scale) and b* (yellow/blue scale) of 1142 eggs were determined. The estimated heritabilities ranged from 0.35 to 0.48 and the genetic correlations between them were high. In general, the genetic correlations between eggshell color and egg quality traits were low, suggesting that the eggshell color does not influence internal and external egg quality.
165

Links between avian botulism outbreaks in waterfowl, hatching asynchrony, and life history trade-offs of prefledgling Franklin's gulls (<i>larus pipixcan</i>)

Soos, Catherine 01 December 2004
This study investigated factors associated with two mortality events: avian botulism in waterfowl and mortality associated with hatching asynchrony in prefledgling Franklins gulls (Larus pipixcan). The initial focus of my research was on the spatiotemporal relationship between mortality of Franklins gulls and the onset of botulism outbreaks in waterfowl, and the suitability of gull carcasses for proliferation and toxigenesis of Clostridium botulinum. From 1999 to 2001, dead hatch-year Franklins gulls were by far the most abundant carcasses, and the only source of toxin-laden maggots found on transects prior to the occurrence of avian botulism in waterfowl. Nest density was a significant predictor of hatch-year gull carcass density. High density of toxic material from gull carcasses prior to the onset of botulism in waterfowl coincided with high densities of susceptible birds; hence, mortality of Franklins gulls has the potential to be a major initiating factor for botulism outbreaks at Eyebrow Lake, Saskatchewan. The causes of gull mortality were conditions or diseases associated with starvation, stress, or immunosuppression, and most mortality occurred in third-hatched chicks. To separate effects of laying order from effects of hatching asynchrony on prefledgling survival, a cross-fostering experiment was conducted to create clutches containing asynchronously hatching eggs of the same laying order, and of similar egg mass, egg volume, and female quality. Hatching order, independent of laying order, significantly affected survival to fledging, whereas laying order had no observable effect, indicating that intraclutch variation in egg quality does not predetermine the fate of prefledglings, and may be less important than hatching asynchrony for survival of prefledgling Franklins gulls. Relationships among hatching asynchrony, laying order, mass, corticosterone, immune function, growth, and survival at two stages of development were complex. Hatching asynchrony significantly affected early and late prefledgling survival, and was directly or indirectly associated with mass, corticosterone level, and cell-mediated immune responses at early and later stages of development. Both hatching asynchrony and mass appeared to play key roles in mediating life history trade-offs among cell-mediated immune function, growth, and survival. In contrast to cell-mediated immune responses, primary humoral immune response was not directly affected by hatching order or mass, nor was it associated with survival to fledging. Rather, it was associated with laying order, neonatal testosterone, corticosterone at 2 weeks, growth of leg length, and clutch initiation date, illustrating the importance of examining more than one branch of the immune system in studies of life history trade-offs. This study is a step toward using a multipronged and multidisciplinary approach to demonstrate interactions and trade-offs among life history traits, the physiological mechanisms that produce these relationships, and how these relationships may change depending on stage of development.
166

Links between avian botulism outbreaks in waterfowl, hatching asynchrony, and life history trade-offs of prefledgling Franklin's gulls (<i>larus pipixcan</i>)

Soos, Catherine 01 December 2004 (has links)
This study investigated factors associated with two mortality events: avian botulism in waterfowl and mortality associated with hatching asynchrony in prefledgling Franklins gulls (Larus pipixcan). The initial focus of my research was on the spatiotemporal relationship between mortality of Franklins gulls and the onset of botulism outbreaks in waterfowl, and the suitability of gull carcasses for proliferation and toxigenesis of Clostridium botulinum. From 1999 to 2001, dead hatch-year Franklins gulls were by far the most abundant carcasses, and the only source of toxin-laden maggots found on transects prior to the occurrence of avian botulism in waterfowl. Nest density was a significant predictor of hatch-year gull carcass density. High density of toxic material from gull carcasses prior to the onset of botulism in waterfowl coincided with high densities of susceptible birds; hence, mortality of Franklins gulls has the potential to be a major initiating factor for botulism outbreaks at Eyebrow Lake, Saskatchewan. The causes of gull mortality were conditions or diseases associated with starvation, stress, or immunosuppression, and most mortality occurred in third-hatched chicks. To separate effects of laying order from effects of hatching asynchrony on prefledgling survival, a cross-fostering experiment was conducted to create clutches containing asynchronously hatching eggs of the same laying order, and of similar egg mass, egg volume, and female quality. Hatching order, independent of laying order, significantly affected survival to fledging, whereas laying order had no observable effect, indicating that intraclutch variation in egg quality does not predetermine the fate of prefledglings, and may be less important than hatching asynchrony for survival of prefledgling Franklins gulls. Relationships among hatching asynchrony, laying order, mass, corticosterone, immune function, growth, and survival at two stages of development were complex. Hatching asynchrony significantly affected early and late prefledgling survival, and was directly or indirectly associated with mass, corticosterone level, and cell-mediated immune responses at early and later stages of development. Both hatching asynchrony and mass appeared to play key roles in mediating life history trade-offs among cell-mediated immune function, growth, and survival. In contrast to cell-mediated immune responses, primary humoral immune response was not directly affected by hatching order or mass, nor was it associated with survival to fledging. Rather, it was associated with laying order, neonatal testosterone, corticosterone at 2 weeks, growth of leg length, and clutch initiation date, illustrating the importance of examining more than one branch of the immune system in studies of life history trade-offs. This study is a step toward using a multipronged and multidisciplinary approach to demonstrate interactions and trade-offs among life history traits, the physiological mechanisms that produce these relationships, and how these relationships may change depending on stage of development.
167

Nesting and migration in the introduced Canada goose in Sweden

Sjöberg, Göran January 1993 (has links)
The aim of the thesis was to document patterns in breeding and migration in Swedish Canada geese Branta canadensis, to explain these against the genetic and historical background of the population, and to test predictions of hypotheses pertaining to parental investment. The Canada goose population in Sweden was founded by the introduction of a few individuals in the 1930's. DNA fingerprint similarity between geese breeding in Sweden was on average at the same level as between inbred close relatives in other wild bird species. The genetic variability of the population appeared to be considerably reduced in comparison to that of Canada geese breeding in North America. Dispersal and migration patterns were studied using plastic neck-bands that could be identified at long distance. Most Canada goose females nested at the lake where they grew up. Males were more prone to disperse than females, although most of them still returned to breed close to their area of origin. Geese from three breeding areas in Sweden had different winter distributions, although wintering areas overlapped considerably. Individual geese tended to return to the same wintering area as they had used in previous years. The females' investment in the egg clutch was related to the migration distance from spring foraging areas to the nesting area, suggesting an energetic cost of migration for egg production. Within breeding seasons, clutch size decreased with later initiation of nesting, but only in years with early breeding. A probable reason for this decrease was that body reserves available for egg production were larger in early layers. In years with late breeding, clutch size did not decrease, most likely because late-nesting females could supplement their body reserves by foraging on fresh vegetation. Nest defence intensity was studied by recording the behaviour of the female geese when a human approached the nest. The results largely confirmed predictions for nest defence intensity extracted from parental investment theory. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1993, härtill 6 uppsatser</p> / digitalisering@umu
168

Realisierung einer Demonstratoranlage für die Orbitalwickeltechnologie

Wallasch, Rainer, Tirschmann, Ramon, Spieler, M., Nendel, W., Kroll, L. 06 July 2015 (has links) (PDF)
Im Rahmen des Exzellenzclusters MERGE an der TU Chemnitz erfolgt die Entwicklung eines kontinuierlichen großserientauglichen Verfahrens zur Herstellung komplexer geschlossener Strukturbauteile. Hierbei werden vorimprägnierte faserverstärkte thermoplastische Halbzeuge (thermoplastische Tapes) in einem Kombinationsverfahren aus thermoplastischen Tapelegen und Tapewickeln verarbeitet. Für dieses kontinuierliche Orbitalwickelverfahren wurde ein spezieller Technologiedemonstrator entwickelt mit dessen Hilfe Machbarkeitsstudien zur Erbringung des Funktionsnachweises durchgeführt werden. Die oben genannte Versuchsanlage ermöglicht die Erzeugung rotationssymmetrischer Profile, die zudem einen inkonstanten Querschnitt aufweisen können. Für die Anlagenkonzeptionierung wurde ein Beispielprofil eines Strukturbauteils ausgewählt und die Anlagendimensionierung durchgeführt. Basierend auf dem Entwurf werden zur Anlagendimensionierung die Parameter der Einzelantriebe mit Hilfe inverser Kinematik simulativ und analytisch abgeleitet und durch anschließende Simulation in CreoElements/Pro® vervollständigt. Die konstruktive Realisierung erfolgte mittels Solid Works. Die abschließende simulative Validierung wurde wiederum mittels CreoElements/Pro® durchgeführt. Diese Arbeiten entstanden im Rahmen des Bundesexzellenzclusters EXC 1075 "Technologiefusion für multifunktionale Leichtbaustrukturen" und wurde von der Deutschen Forschungsgemeinschaft gefördert. Die Autoren danken für die finanzielle Unterstützung.
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Modeling of Particulate Matter Emissions from Agricultural Operations

Bairy, Jnana 1988- 02 October 2013 (has links)
State Air Pollution Regulation Agencies (SAPRAs) issue and enforce permits that limit particulate matter emissions from all sources including layer and broiler facilities, cattle feedyards, dairies, cotton gins, and grain elevators. In this research, a process was developed to determine distances from emitting sources to where the estimated concentrations were less than the National Ambient Air Quality Standards (NAAQS). These distances are a function of emission rates and meteorological conditions. Different protocols were used to develop emission factors for cattle feedyards and layer houses. Dispersion modeling with American Meteorological Society/Environmental Protection Agency Regulatory Model (AERMOD) was conducted to determine the emissions of particulate matter. These data were used to determine the distances from the sources to where the concentrations of particulate matter (PM) would be less than the NAAQS. The current air-permitting process requires that concentrations from a source do not exceed the NAAQS at the property line and beyond for the facility to be in compliance with its permit conditions. Emission factors for particulate matter less than 10 micrometers (PM10) were developed for cattle feedyards using a reverse modeling protocol and Tapered Element Oscillating Microbalance (TEOM) sampler data. Corrections were applied to the TEOM measurements to account for TEOM vs. filter-based low-volume (FBLV) sampler bias and over-sampling of PM10 pre-collectors. Invalid concentrations and dust peaks larger than mean ± 3 times the standard deviation were excluded from this study. AERMOD predictions of downwind concentrations at cotton gins were observed for compliance with 24-hour PM10 and PM2.5 NAAQS at property lines. The emissions from three cotton gins were analyzed at 50 m and 100 m distances. TEOM and FBLV samplers were used to collect 24-hour PM10 measurements inside a laying hen house. The distances to the property lines at which the emissions of PM10 were below the 24-hour average PM10 standards were estimated using AERMOD. The results suggested that the special use of the NAAQS for as the property-line concentration not to be exceeded, could be problematic to agriculture. Emission factors that were comparable of published emission factors were obtained in this study. Large distances to property lines were required when minimum flow rate recommendations were not considered. Emission factors that are representative of the emissions in a particular facility are essential; else facilities could be inappropriately regulated.
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Modélisation du devenir de l’hexabromocyclododécane (HBCD) chez la poule pondeuse : influence des caractéristiques physiologiques / Modelling the hexabromocyclododecane (HBCD) transfer kinetics in the laying hen : impact of the physiological features

Domínguez-Romero, Elena 21 November 2016 (has links)
L’hexabromocyclododécane (HBCD) a été utilisé comme additif dans des polystyrènes (PS). En 2013, l’HBCD a été inclus à la Convention de Stockholm comme Polluant Organique Persistant. Les denrées alimentaires d’origine animale (DAOA) constituent la source principale d’exposition de la population générale à ce polluant. Le niveau moyen d’exposition du consommateur ne représente pas un risque majeur pour la sécurité sanitaire des aliments (EFSA, 2011). Malgré des concentrations moyennes généralement proches d’un ng g-1 lipides dans les DAOA, des concentrations maximales supérieures à 2000 ng g-1 lipides dans certains échantillons d’œuf ont été rapportées. Plusieurs sources potentielles d’exposition orale des volailles existent. Les poules pondeuses pourraient être exposées majoritairement à l’isomère α-HBCD. Au vu de l’absence d’informations dans la littérature sur le devenir de l’α-HBCD chez la poule pondeuse, une expérimentation in vivo a été réalisée et a permis d’estimer la plupart des paramètres cinétiques du devenir de l’α-HBCD ingéré chez la poule pondeuse. Un modèle pharmacocinétique basé sur la physiologie (PBPK) de transfert de l’α-HBCD chez la poule pondeuse a été développé, calibré par des données de la littérature, soumis à analyse de sensibilité et plusieurs paramètres ont été ajustés sur des résultats in vivo. Une validation du modèle a été testée. Ce modèle a permis de déterminer l’influence des caractéristiques physiologiques de la poule pondeuse sur le devenir de l’α-HBCD en cas d’exposition à la molécule. Parmi les caractéristiques d’intérêt, le poids vif (PV) est celle qui influence le plus la concentration d’α-HBCD dans les tissus et les œufs. Un PV bas et des performances de ponte réduites prédisposent à une concentration plus élevée dans ces matrices. La mue produit une augmentation de la charge corporelle de la molécule. Ce modèle peut être extrapolé à d’autres animaux et molécules lipophiles après modification de certains paramètres / Hexabromocyclododecane (HBCD) has been used as an additive in polystyrene (PS). In 2013, HBCD was included in the Stockholm Convention as a Persistent Organic Pollutant. The foodstuffs of animal origin are the main source of exposure of the general population to this pollutant. The mean exposure level of the consumers to HBCD doesn’t represent a major risk to the food safety (EFSA, 2011). In spite of mean concentrations generally close to 1 ng g-1 lipids in the foodstuffs of animal origin, maximal concentrations higher than 2000 ng g-1 lipids have been reported in some egg samples. There are several potential sources of oral exposure of the hens to this pollutant. The hens could be exposed mainly to the α-HBCD isomer. Since the bibliographic synthesis highlights the absence of information about the α-HBCD kinetics in the laying hen, an in vivo experience has been realized and has allowed the estimation of the majority of the α-HBCD kinetic parameters in the laying hen. A physiologically based pharmacokinetic (PBPK) model has been developed, calibrated by literature data, submit to a sensitivity analysis and some parameters have been adjusted on the basis of experimental data. A validation of the model has been attempted. This model has allowed to determine the influence of the main physiological characteristics of the laying hen exposed to the molecule on the α-HBCD accumulation in tissues and transfer to eggs. Among the physiological characteristics of concern, the body weight (BW) is the main feature influencing the α-HBCD kinetics. If the hen is exposed to the α-HBCD, a low BW and low laying performances predispose the hen to have higher concentrations of the molecule in all the matrices. The molting stage raises the body charge of the molecule. This model can be extrapolated to other animals and lipophilic molecules after modification of some parameters

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