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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.
71

Machine Learning Algorithms for Geometry Processing by Example

Kalogerakis, Evangelos 18 January 2012 (has links)
This thesis proposes machine learning algorithms for processing geometry by example. Each algorithm takes as input a collection of shapes along with exemplar values of target properties related to shape processing tasks. The goal of the algorithms is to output a function that maps from the shape data to the target properties. The learned functions can be applied to novel input shape data in order to synthesize the target properties with style similar to the training examples. Learning such functions is particularly useful for two different types of geometry processing problems. The first type of problems involves learning functions that map to target properties required for shape interpretation and understanding. The second type of problems involves learning functions that map to geometric attributes of animated shapes required for real-time rendering of dynamic scenes. With respect to the first type of problems involving shape interpretation and understanding, I demonstrate learning for shape segmentation and line illustration. For shape segmentation, the algorithms learn functions of shape data in order to perform segmentation and recognition of parts in 3D meshes simultaneously. This is in contrast to existing mesh segmentation methods that attempt segmentation without recognition based only on low-level geometric cues. The proposed method does not require any manual parameter tuning and achieves significant improvements in results over the state-of-the-art. For line illustration, the algorithms learn functions from shape and shading data to hatching properties, given a single exemplar line illustration of a shape. Learning models of such artistic-based properties is extremely challenging, since hatching exhibits significant complexity as a network of overlapping curves of varying orientation, thickness, density, as well as considerable stylistic variation. In contrast to existing algorithms that are hand-tuned or hand-designed from insight and intuition, the proposed technique offers a largely automated and potentially natural workflow for artists. With respect to the second type of problems involving fast computations of geometric attributes in dynamic scenes, I demonstrate algorithms for learning functions of shape animation parameters that specifically aim at taking advantage of the spatial and temporal coherence in the attribute data. As a result, the learned mappings can be evaluated very efficiently during runtime. This is especially useful when traditional geometric computations are too expensive to re-estimate the shape attributes at each frame. I apply such algorithms to efficiently compute curvature and high-order derivatives of animated surfaces. As a result, curvature-dependent tasks, such as line drawing, which could be previously performed only offline for animated scenes, can now be executed in real-time on modern CPU hardware.
72

Machine Learning Algorithms for Geometry Processing by Example

Kalogerakis, Evangelos 18 January 2012 (has links)
This thesis proposes machine learning algorithms for processing geometry by example. Each algorithm takes as input a collection of shapes along with exemplar values of target properties related to shape processing tasks. The goal of the algorithms is to output a function that maps from the shape data to the target properties. The learned functions can be applied to novel input shape data in order to synthesize the target properties with style similar to the training examples. Learning such functions is particularly useful for two different types of geometry processing problems. The first type of problems involves learning functions that map to target properties required for shape interpretation and understanding. The second type of problems involves learning functions that map to geometric attributes of animated shapes required for real-time rendering of dynamic scenes. With respect to the first type of problems involving shape interpretation and understanding, I demonstrate learning for shape segmentation and line illustration. For shape segmentation, the algorithms learn functions of shape data in order to perform segmentation and recognition of parts in 3D meshes simultaneously. This is in contrast to existing mesh segmentation methods that attempt segmentation without recognition based only on low-level geometric cues. The proposed method does not require any manual parameter tuning and achieves significant improvements in results over the state-of-the-art. For line illustration, the algorithms learn functions from shape and shading data to hatching properties, given a single exemplar line illustration of a shape. Learning models of such artistic-based properties is extremely challenging, since hatching exhibits significant complexity as a network of overlapping curves of varying orientation, thickness, density, as well as considerable stylistic variation. In contrast to existing algorithms that are hand-tuned or hand-designed from insight and intuition, the proposed technique offers a largely automated and potentially natural workflow for artists. With respect to the second type of problems involving fast computations of geometric attributes in dynamic scenes, I demonstrate algorithms for learning functions of shape animation parameters that specifically aim at taking advantage of the spatial and temporal coherence in the attribute data. As a result, the learned mappings can be evaluated very efficiently during runtime. This is especially useful when traditional geometric computations are too expensive to re-estimate the shape attributes at each frame. I apply such algorithms to efficiently compute curvature and high-order derivatives of animated surfaces. As a result, curvature-dependent tasks, such as line drawing, which could be previously performed only offline for animated scenes, can now be executed in real-time on modern CPU hardware.
73

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.
74

Cultivo de Dendrocephalus brasiliensis (Pesta, 1921) visando à aplicação em aquicultura

Silva, Ricardo Augusto Custodio da 07 March 2016 (has links)
Submitted by Daniele Amaral (daniee_ni@hotmail.com) on 2016-10-20T19:44:51Z No. of bitstreams: 1 TeseRACS.pdf: 3547391 bytes, checksum: fe9bc399d15d41ee702720017aabc920 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-11-08T18:43:52Z (GMT) No. of bitstreams: 1 TeseRACS.pdf: 3547391 bytes, checksum: fe9bc399d15d41ee702720017aabc920 (MD5) / Approved for entry into archive by Marina Freitas (marinapf@ufscar.br) on 2016-11-08T18:44:01Z (GMT) No. of bitstreams: 1 TeseRACS.pdf: 3547391 bytes, checksum: fe9bc399d15d41ee702720017aabc920 (MD5) / Made available in DSpace on 2016-11-08T18:44:08Z (GMT). No. of bitstreams: 1 TeseRACS.pdf: 3547391 bytes, checksum: fe9bc399d15d41ee702720017aabc920 (MD5) Previous issue date: 2016-03-07 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / The hatchery is now the main obstacle of aquaculture. Live food, especially zooplankton, is essential in the first life stages of fish. However, there are difficulties in obtaining sufficient biomass. The Anostraca Dendrocephalus brasiliensis, known as “branconeta”, has great potential for use in national aquaculture. In this study, experiments were conducted in controlled conditions in order to obtain: I) the best conditions for hatching of resistant cysts, evaluating the cyst density in the sediment, temperature and pH of the water, and cysts dehydration time; II) identification of the early stages of life, focusing on the length and time to maturity, and we also investigate the main factors that influence the development of the early stages and; III) semiintensive production, the organisms were grown during winter and summer, with two different diets and subsequent analysis of the biochemical composition of organisms grown in these conditions. Hatching occurs in low proportions, and is mainly influenced by the density of cysts present in the sediment, and show some tolerance to different levels of temperature and pH. The average time to reach adulthood was ten days and during the early stages, we observed that some individuals have delayed hatching. Among the environmental variables, temperature and conductivity play a major role in the growth during this period, along with the food, which must be provided from the third day. In semi-intensive farming conditions, we found that large amounts of food promote greater growth in length, both in summer and winter, however, during the winter, low amounts of food provide greater survival. In biochemical analysis, individuals grown with a low amount of food had higher proportion of protein, values higher than those found in Artemia sp. We also detected the presence of polyunsaturated fatty acids, which are of great interest in organisms to be used as live food for fish. In general, D. brasiliensis can be regarded as a suitable species for use in aquaculture due to: ease handling of cysts, since cysts present in the sediment are sufficient for obtaining large populations; growth rate and high tolerance to ambient changes, not requiring great efforts in keeping the culture medium and; nutritional quality, with high concentration of proteins and the presence of polyunsaturated fatty acids. / A larvicultura é hoje o principal entrave da aquicultura. O alimento vivo, em especial zooplanctônico, é essencial nas fases jovens de peixes. No entanto, há dificuldades em se obter biomassa suficiente. O Anostraca Dendrocephalus brasiliensis, conhecido como branconeta, tem grande potencial de utilização na aquicultura nacional. No presente estudo, foram realizados experimentos controlados a fim de se obter: I) melhores condições para eclosão dos cistos de resistência, avaliando a densidade de cistos no sedimento, temperatura e pH da água, e tempo de desidratação dos cistos; II) identificação dos estágios iniciais de vida, com enfoque no comprimento e tempo até a maturidade, além de investigarmos os principais fatores que influenciam o desenvolvimento das fases iniciais e; III) produção semi-intensiva, com cultivos realizados durante o inverno e o verão, com dois regimes alimentares distintos e posterior análise da composição bioquímica dos organismos cultivados nestas condições. A eclosão ocorre em baixas proporções e é influenciada principalmente pela densidade de cistos presente no sedimento, tendo certa tolerância a diferentes níveis de temperatura e pH. O tempo médio para se atingir a idade adulta foi de dez dias e durante as fases inicias, observamos que alguns indivíduos apresentam eclosão tardia. Dentre as variáveis ambientais estudadas, temperatura e condutividade desempenham papel principal no crescimento durante esse período, juntamente com a alimentação, a qual deve ser fornecida a partir do terceiro dia. Em condições de cultivo semi-intensivo, constatamos que grandes quantidades de alimento promovem maior crescimento em comprimento, tanto no verão quanto no inverno, contudo, durante o inverno, baixas quantidades de alimento conferem maior sobrevivência. Na análise bioquímica, os indivíduos cultivados em regime com baixa quantidade de alimento apresentaram maior proporção de proteínas, valores estes maiores do que aqueles encontrados em Artemia sp. Também detectamos a presença de ácidos graxos poliinsaturados, que são de grande interesse em organismos a serem utilizados como alimento vivo para peixes. De modo geral, D. brasiliensis pode ser considerada uma espécie propícia ao uso na aquicultura, devido à: facilidade no manejo de cistos, uma vez que cistos presentes no sedimento são suficientes para obtenção de grandes populações; alta taxa de crescimento e tolerância às variações ambientes, não exigindo grandes esforços na manutenção do meio de cultivo e; qualidade nutricional, com alta concentração de proteínas e presença de ácidos graxos poliinsaturados. / 2008/02078-9
75

Otimização do sistema de produção in vitro de embriões suínos / Optimization of the porcine in vitro embryo production system

Klein, Norton 19 July 2013 (has links)
Made available in DSpace on 2016-12-08T16:24:14Z (GMT). No. of bitstreams: 1 PGCA13MA112.pdf: 807586 bytes, checksum: b293744892841538c2ea9e0a5ae8325a (MD5) Previous issue date: 2013-07-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The in vitro production of pig embryos progressed significantly in the last decade. However, the embryo growing rates remain variable and with low embryonic quality. The chromosomal abnormalities as a result of high polyspermy rates and the inefficient culture systems are pointed as the main problems. Thus, the aim of this study was to improve the rates of monospermy, and also the hatching rates of in vitro produced porcine embryos. The first study investigated decreasing sperm concentrations combined with different incubation periods during in vitro fertilization (IVF). A total of 829 oocytes were matured and allocated in two experiments. In the first, oocytes were IVF using different sperm concentrations (62.5, 125, 187.5 or 250 x 103 sperm / mL). In the second experiment the oocytes were IVF using 62.5 x 103 sperm / mL pointed in experiment 1, for 2, 3 or 4 hours incubation time. Then the zygotes were cultured during twelve hours to evaluate the fertilization parameters, or during seven days to evaluate embryonic development. A third experiment was performed to evaluate the sperm acrosome reaction according to the incubation period. The higher sperm concentration reduced embryo production from 33.9% to 13.4%. The reduction of the incubation period from 4 to 3 or 2 hours significantly increased the rates of cleavage (42.1 to 71.6% and 73.3%), embryo development (14 to 34.7 and 38.9%) and hatching (25 to 66.7 and 65.7%. Increased sperm concentration and incubation period significantly altered the parameters related to fertilization, substantially impairing the monospermic embryos production. The number of sperm with reacted acrosome increased significantly as incubation time was increased. In the second study we evaluated the assisted hatching of porcine embryos IVP by zona pellucid incision or treatment with pronase. Oocytes were matured and in vitro fertilized with 62.5 x 103 spermatozoa / mL concentration for three hours. The zygotes were cultured for seven days, and then embryonic development and hatching rates evaluated. It was also determined the cell density and cell apoptosis rates of hatched embryos. Both the manual incision or pronase digestion were effective in weakening the ZP of embryos with high cell density. However, it was observed a reduction in the survival rates, and higher apoptosis rates in hatched embryos treated with Pronase. With basis on the data we concluded that a reduction in sperm concentration and incubation period decreases the incidence of polyspermy and improves the embryo development rates. This is probably due to reduction of capacitated /reacted sperm available for fertilization. Also, the weakening of the zona pellucid by incision improves significantly the number and quality of embryos hatched at the end of embryo culture / A produção in vitro de embriões suínos avançou significativamente na última década. Entretanto, os índices de desenvolvimento embrionário continuam inconstantes e a qualidade dos embriões extremamente baixa. A incidência de anormalidades cromossômicas decorrentes das altas taxas de polispermia e a ineficiência dos sistemas de cultivo são apontados como os principais impasses. Desta forma, este estudo buscou melhorar os índices de monospermia, e as taxas de eclosão dos embriões suínos produzidos in vitro. O primeiro estudo investigou a utilização de diferentes concentrações espermáticas e períodos de incubação dos gametas durante a fecundação in vitro (FIV). Para tanto, um total de 829 oócitos foram maturados e destinados à dois experimentos. No primeiro, os oócitos foram FIV utilizando diferentes concentrações espermáticas (62.5, 125, 187.5 ou 250 x 103 espermatozoides/mL). No segundo, os oócitos foram FIV utilizando 62.5 x 103 espermatozoides/mL durante duas, três ou quatro horas. Após a FIV os zigotos foram cultivados por doze horas para análise dos parâmetros da fertilização ou por sete dias para o estudo do desenvolvimento embrionário. Um terceiro experimento avaliou o número de espermatozóides com acrossoma reagido de acordo com o período de incubação. A máxima concentração de espermatozóides reduziu a produção embrionária (de 33.9% para 13.4%). Já a redução do período de incubação de quatro para três ou duas horas, aumentou significativamente as taxas de clivagem (42.1% para 71.6 e 73.3%), de desenvolvimento embrionário (14% para 34.7 e 38.9%) e de eclosão (25% para 66.7 e 65.7%). Tanto o aumento da concentração espermática, como o aumento período de incubação alteraram significativamente a maioria dos parâmetros relacionados a fecundação, prejudicando substancialmente a produção de embriões monospérmicos. O número de espermatozoides com acrossoma reagido aumentou significativamente com o pronlongamento da fecundação. No segundo estudo, investigou-se a indução da eclosão assistida de embriões suínos PIV através da incisão da zona pelúcida ou pelo tratamento com pronase. Os oócitos foram maturados e fecundados in vitro com uma concentração de 62.5 x 103 espermatozóides/mL por três horas. Os zigotos foram cultivados durante sete dias, então, avaliados quanto ao desenvolvimento embrionário e a incidência de eclosão. Determinamos também a densidade celular e os índices de apoptose celular dos embriões eclodidos. Tanto a incisão da zona como a digestão com pronase foram efetivos na fragilização da ZP dos embriões com alta densidade celular. Todavia, constatou-se uma redução da sobrevivência e aumento do índice de apoptose celular dos embriões eclodidos pelo tratamento com pronase. Com base nos dados obtidos concluímos que a redução da concentração de espermatozóides e do período de incubação diminuem a incidência de polispermia e melhoram o desenvolvimento embrionário. Isto é provavelmente devido a redução da disponibilidade de espermatozóides capacitados/reagidos para a fecundação. Da mesma forma, a fragilização da zona pelúcida através da incisão, melhora significativamente o número e a qualidade dos embriões eclodidos ao final do cultivo embrionário
76

Efeitos da maltodextrina como aditivo via água de bebida na recepção de pintainhos submetidos a quatro períodos de jejum pós-eclosão

Machado, Camila Alves 14 October 2010 (has links)
CHAPTER 2: The objective of this research was to evaluate the effects of fasting time on bromatology carcass, biometrics organ, water intake and performance of broiler chickens. We conducted a randomized design consisting of four days of fasting after hatching (0, 12, 24 and 36 hours) and four replications. Therefore, 640 birds were distributed in sixteen boxes containing 20 females and 20 males each. Water consumption was greater the longer the duration of fasting and was greater weight loss from hatching to the accommodation. There was also the weight loss on the yolk sac. Fasting influenced the relative weight of all organs of the digestive tract except esophagus + craw that remained unchanged. With increasing fasting time increased the relative weight of the esophagus+craw, proventriculus+gizzard, intestine+ pancreas, intestine and liver+gallbladder. However, food science and animal performance were not affected by fasting. CHAPTER 3: The objective of this research was to evaluate the effect of maltodextrin on performance and biometry of the digestive organs in chicks underwent four fasting time. Was performed a completely randomized design consisting of three treatments (1 - control, 2 - 4% sugar; 3-4% maltodextrin 20) and four times of fasting after hatching (0, 12, 24 and 36 hours) with four replications , 1920 birds in total of both sexes. The results showed that both the maltodextrin as sugar stimulated the consumption of water and after 24 hours, the group that has not been pass of fasting and was approved with maltodextrin obtained with greater weight of the small intestine and pancreas, besides a greater length of the gastrointestinal tract. The performance at 42 days was not influenced by the use of additives, however, the viability suffered positive influence after seven days of life. / CAPÍTULO 2: Objetivou-se com esta pesquisa avaliar os efeitos do tempo de jejum sobre a bromatologia da carcaça, biometria dos órgãos, consumo de água e desempenho zootécnico de frangos de corte. Foi realizado um delineamento inteiramente casualizado composto por quatro períodos de jejum pós-eclosão (0, 12, 24 e 36 horas) e quatro repetições. Para tanto, 640 aves foram distribuídas em dezesseis boxes, contendo 20 fêmeas e 20 machos cada. O consumo de água foi maior quanto maior o tempo de jejum, e maior foi à perda de peso desde a eclosão até o alojamento. Ocorreu também a perda de peso relativo do saco vitelino. O jejum influenciou o peso relativo de todos os órgãos do trato digestivo, exceto esôfago+papo que permaneceram inalterados. Com o aumento do tempo de jejum aumentou o peso relativo do esôfago+papo, proventrículo+moela, intestino delgado+pâncreas, intestino grosso e fígado+vesícula biliar. No entanto, a bromatologia e o desempenho zootécnico não foram influenciados pelo jejum. CAPÍTULO 3: Objetivou-se com esta pesquisa avaliar o efeito da maltodextrina sobre o desempenho zootécnico e biometria dos órgãos digestivos em pintainhos submetidos a quatro períodos de jejum. Foi executado um delineamento experimental inteiramente casualizado composto por três tratamentos (1 controle; 2 4% de açúcar; 3 4% de maltodextrina 20) e quatro tempos de jejum póseclosão (0, 12, 24 e 36 horas) com quatro repetições, contendo no total 1920 aves de ambos os sexos. Os resultados mostraram que tanto a maltodextrina quanto o açúcar estimularam o consumo de água e depois de 24 horas o grupo que não sofreu jejum e foi recepcionado com maltodextrina obteve maior peso de intestino delgado e pâncreas, além de maior comprimento do trato gastrintestinal. O desempenho zootécnico aos 42 dias não foi influenciado pela utilização de aditivo, no entanto, a viabilidade sofreu influencia positiva aos sete dias de vida. / Mestre em Ciências Veterinárias
77

REPRODUKCE PARMY OBECNÉ (Barbus barbus L.) V KONTROLOVANÝCH PODMÍNKÁCH. / REPRODUCTION OF BARBEL (Barbus barbus L.) UNDER CONTROLLED CONDITIONS.

VAVREČKA, Antonín January 2008 (has links)
Barbel (Barbus barbus L.) is autochthonous species with batch-spawning, incident in the whole territory in the Czech republic. Number of this species was decrease markedly at last thirty years ago. Continual fish production is possible obtained to creation breeding under controlled conditions. Aim of thesis was detect basic characteristics of reproduktion under controlled conditions in fish breeding object VÚHR JU Vodňany. Fertilization, hatching performance was detect and quality offspring by osmotic test subsequently. These realized valuables about domesticated barbel were compared with same valuables hormonal induce ovulation adult fish and with valuables in spawning barbel directly in place of catching. The best results fertilization, hatching performance and resistance of larvae were reached in barbel spawning after cathing fish in the river Doubrava (Čáslavsko). After that follows group fish treated by hormonal preparation in the hatchery in Třebíč. Domesticated barbel spawning from January to June in periodic intervals, but their characteristics of reproduction are the worst demonstrably.
78

Desenvolvimento de embriões e pintos de corte provenientes de ovos de diferentes pesos e idades de matriz e níveis de aminoácidos sulfurados na fase póseclosão / Development of embryos and broilers obtained from different egg weights and breeder ages and sulphur aminoacids supplementation in post hatch phase

FERREIRA, Lídia Lopes 01 March 2010 (has links)
Made available in DSpace on 2014-07-29T15:07:30Z (GMT). No. of bitstreams: 1 Dissertacao Lidia Lopes Ferreira 2010.pdf: 451171 bytes, checksum: 0d7a5a0e428d7b2d0cf4f49c7b1b9d10 (MD5) Previous issue date: 2010-03-01 / Aiming to evaluate the effects of broiler breeder´s age and egg weight on the performance, two experiments were conducted using increasing levels of sulfur amino acids. For each experiment, 320 chicks from a commercial hatchery were used. The experimental design was randomized blocks due to the sex of chicks in a 2x4 factorial arrangement. The chicks´ performance was evaluated according to the breeders age and the egg weight combined with high levels of methionine and digestible cystine in the pre-starter ration (0.810, 0.910, 1.010 and 1.110%), in a total of eight experimental groups and four replicates of 10 birds each, The eggs were separated, weighed and distributed in a stroller in a commercial incubator, with constant temperature at 37.8 ºC and humidity between 60 and 65%. Chicks from old and new breeders and two different egg weights were submitted to necropsy, biometry of the intestinal tract (GIT) organs, and intestinal histomorphometry were performed. Blood was collected for glucose analysis at 19 days of embryo, and after hatching, at seven and 14 days of life. The rest of the chicks were submitted to a metabolism trial at four and seven days of age, by the method of excreta collection and the nitrogen balance was determined (g). Other autopsies were carried out at seven and 14 days of life with the performance of the same analyses previously described. The broilers performance was not evaluated up to 21 days of life. Data were submitted to analysis of variance and polynomial regression for the levels of sulfur amino acids according to SAS (2004). A higher initial development was observed in young breeders for both biometry of digestive organs and intestine histomorphometry .This development is more evident in chicks of older breeders. The differences found in the experiment with different egg weights show a better development of embryos and chicks for eggs weighing 70 g. Chicks from 70-g-eggs and 45-week-old breeders were heavier. Average levels of 0.910% and 1.010% of methionine + digestible cystine in the pre-starter ration resulted in performance and nutrient retention more suitable for broiler chicks in both experiments. Based on feed conversion, we suggest the minimum recommendation of 0.810%. / Com o objetivo de avaliar os efeitos da idade da matriz de frango de corte e do peso dos ovos foram conduzidos dois experimentos em que se discute sua relação com o desempenho utilizando níveis crescentes de aminoácidos sulfurados. Para cada experimento utilizaram-se 320 pintos provenientes de um incubatório comercial. O delineamento experimental foi em blocos casualizados devido ao sexo dos pintos, em esquema fatorial 2x4. Foi avaliado o desempenho dos pintos com idades de matrizes e peso dos ovos combinado com níveis de metionina+cistina digestível na ração pré-inicial (0,810; 0,910; 1,010 e 1,110%), totalizando oito grupos experimentais e quatro repetições de 10 aves cada, considerando os sexos macho e fêmea. Os ovos foram separados, pesados e distribuídos em um carrinho na incubadora comercial e a temperatura foi mantida constante a 37,8ºC e umidade entre 60 e 65%. Foram necropsiados pintos oriundos de matriz nova e velha e dois pesos de ovos, feita a biometria dos órgãos do trato intestinal (TGI), histomorfometria intestinal, coletados sangue para análise de glicose aos 19 dias de embrião, após a eclosão, sete e 14 dias de vida. O restante dos pintos alojados foi realizado um ensaio metabólico aos quatro a sete dias de idade, pelo método da colheita total de excretas e determinado o balanço de nitrogênio (g) e outras necropsias aos sete e 14 dias de vida e realizado as mesmas análises anteriores. No foram avaliados o desempenho dos frangos até 21 dias de idade. Os dados foram submetidos à análise de variância e realizado regressão polinomial para níveis de aminoácidos sulfurados de acordo com o programa computacional SAS (2004). Observou um maior desenvolvimento inicial em matrizes jovens tanto para biometria dos órgãos digestores quanto para histomorfometria intestinal sendo que esse desenvolvimento é mais evidente pintos de matrizes mais velhas. Já as diferenças encontradas no experimento de diferentes pesos de ovos foram um melhor desenvolvimento de embriões e pintos para pesos de ovos com 70 gramas. Pintos oriundos de ovos com 70 gramas e de matrizes com 45 semanas foram mais pesados. Níveis médios de 0,910% e 1,010% metionina+cistina digestível na fase pré-inicial propiciaram resultados de desempenho e retenção de nutrientes mais adequados em pintos de corte em ambos experimentos. Com base na conversão alimentar, sugerese a recomendação mínima de 0,810%
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The Effect of Air Temperature on the Incubation Period and Hatching Success of In Situ Loggerhead Sea Turtle (Caretta caretta) Clutches in Broward County, Florida

Kawana, Lucy Teal 31 July 2013 (has links)
The survival rates of pre-emergent sea turtle hatchlings are critically dependent upon temperature. This study aimed to determine if changes in air temperature can explain some of the variability in hatching success observed over a 12 year period for loggerhead sea turtle (Caretta caretta) nests in Broward County. Air temperature data for the hatching seasons of 1999 to 2010 were obtained from the NOAA National Climatic Data Center’s Fort Lauderdale beach station. The loggerhead sea turtle hatching data collected by the Broward County Sea Turtle Conservation Program from the same time period was examined to assess the potential effects of air temperature on the hatching success and the incubation duration. Mean yearly incubation times were analyzed for trends and compared to mean nesting season temperatures. The relationships between the incubation durations and mean seasonal and intra-seasonal air temperature fluctuations as well as the relationship between hatching success and air temperature was tested for significance. The hatching success was also compared to the incubation times in order to establish if shorter incubation durations, were related to lower hatching success rates. There have been large fluctuations in the average daily hatching success rates ranging from 10 to 100% over the twelve years examined in this study in Broward County. Significant decreases in incubation durations were apparent during times of increasing average air temperatures. In five of the twelve seasons there was also a significant relationship between the hatching success rates and the average air temperature, in which lower hatching success rates were evident during times of higher average air temperatures. There was a significant correlation between the incubation durations and the hatching success rates in six of the seasons as well, suggesting that lower hatching success rates are related to shorter incubation times. The pattern in average yearly hatching success rates were significantly related to the average monthly air temperatures in July suggesting that lower hatching success rates during the month of July were a result of higher temperatures during this time of the hatching season. A better understanding of the effects that air temperature has on loggerhead sea turtle clutches in Broward County can provide future insights for the fluctuating survival rates of sea turtle clutches and if the changes are natural or the result of conservation efforts.
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Beach Nourishment: Effects on the Hatching & Emergence Success Rates of Leatherback (Dermochelys coriacea), Loggerhead (Caretta caretta), and Green (Chelonia mydas) Sea Turtles

Caderas, Jenna 01 July 2016 (has links)
Broward County, Florida is a popular tourism destination. Due to its popularity, much of the shoreline has been modified and natural habitats were replaced with infrastructure such as houses, condominiums, resorts, and restaurants. The same Broward County beaches utilized by tourists and residents are important for three species of nesting sea turtles, including the Leatherback, Dermochelys coriacea, Loggerhead, Caretta caretta, and Green, Chelonia mydas, Turtles. The Broward County Sea Turtle Conservation Program (BCSTCP) collects yearly data in order to study these endangered reptiles. Increased anthropogenic effects including further coastal development (public & private), public beach events, public beach access, as well as natural events, have caused these important nesting beaches to erode and narrow. In an effort to control this erosion damage, Broward County has performed a number of beach nourishment projects. This study found yearly fluctuations in sea turtle hatching and emergence success rates, and years of beach nourishment projects significantly decreased these rates. Yearly hatching data available from Broward County concludes that beach nourishment, as well as hurricanes and tropical storms cause decreases in sea turtle hatching and emergence success rates in Broward County. Additionally, nest depth and sea turtle size increases the hatching and emergence success rates from females that are not too large or too small that nest in Broward County.

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