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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.
91

Efeito do tipo e da forma física da ração pré-inicial e da idade das matrizes sobre o desempenho de frangos de corte / Effects of ingredient composition and processing of pre-starter diet and age of the breeders on the perfomance of chicks and broilers

Amaral, Rejane 20 January 2006 (has links)
O objetivo deste estudo foi avaliar os efeitos da idade de matriz, composição e forma física da dieta pré-inicial (fornecida à base de 200 g por ave) na performance de frangos de corte machos até os 42 dias de idade. Os tratamentos consistiram das combinações de 2 tipos de ração pré-inicial: formuladas com ingredientes de origem vegetal (milho, farelo de soja e soja integral) ou com subprodutos de origem animal (farinha de carne e ossos, farinha de sangue); 2 formas físicas: farelada ou desintegrada e 2 idades de matrizes: jovem (32 semanas) ou adulta (55 semanas), num arranjo fatorial 2x2x2. O experimento foi realizado com 4 repetições de 45 aves, em blocos casualizados. Seguindo-se os tratamentos dietéticos na fase pré-inicial, todas as aves passaram a receber uma ração comum nas fases inicial, crescimento e final. A ração desintegrada no período pré-inicial resultou em maior peso vivo, ganho de peso, consumo de ração e conversão alimentar aos 7 dias de idade em comparação à ração farelada. A inclusão de ingredientes de origem animal nas dietas pré-iniciais resultou em um decréscimo de peso vivo e ganho de peso aos 7 dias de idade, mas não afetou o consumo de ração e a conversão alimentar. Pintos provenientes de matrizes adultas apresentaram maior peso vivo, ganho de peso e consumo de ração quando comparados àqueles provenientes de matrizes jovens na primeira semana de vida, mas a conversão alimentar não foi afetada. A viabilidade dos pintos na primeira semana não foi afetada por nenhum fator. Na primeira semana não foi observada nenhuma interação significativa entre os fatores para as variáveis. A vantagem da dieta desintegrada durante a primeira semana foi evidente para peso vivo e ganho de peso até os 42 dias de idade e a interação entre forma física e idade da matriz indicou uma vantagem para os frangos provenientes de matrizes jovens (143g) em relação àqueles provenientes de matrizes adultas (64g) quando a ração desintegrada foi fornecida. A conversão alimentar aos 42 dias de idade foi melhor quando a dieta desintegrada foi oferecida para pintos provenientes de matrizes jovens (1,685 vs. 1,718), mas não para aqueles provenientes de matrizes adultas (1,693 vs. 1,694). O consumo de ração total foi maior quando as aves receberam ração pré-inicial vegetal do que contendo ingredientes de origem animal, mas o peso vivo, ganho de peso e conversão alimentar não foram afetados. Aves provenientes de matrizes adultas apresentaram maior consumo de ração durante todo o período. A conversão alimentar não foi afetada pelo tipo de ingrediente utilizado na dieta pré-inicial. Os fatores estudados não influenciaram a viabilidade dos frangos até os 42 dias de idade. Conclui-se que a dieta desintegrada no período pré-inicial melhorou a performance de frangos e esta vantagem foi maior para pintos leves. A dieta vegetal no período pré-inicial não causou prejuízo à performance dos frangos. / The purpose of this study was to evaluate the effects of breeder age, composition and physical form of the pre-starter diet (supplied at a rate of 200 g per bird) the male broilers performance up to 42 days of age. The treatments consisted of the combinations of 2 types of prestarter diets: formulated to contain vegetal ingredients (corn, soybean meal, full fat soybean) or including animal ingredients (meat and bone meal, blood meal); 2 physical forms: mashed or crumbled; 2 breeder ages: young breeders (32 weeks old) or mature breeders (55 weeks old) in a 2X2X2 factorial arrangement. The experiment was carried out on 4 replicates of 45 birds, in a completely randomized block design. After receiving the dietary treatments in the pre-starter period all birds were given a common starter, growing and finishing diet. Crumbled feed in the pre-starter period resulted in improved liveweight, weight gain, feed intake and feed conversion up to 7 days of age compared to mashed feed. The inclusion of animal ingredients into the prestarter diets decreased liveweight and weight gain up to the age of 7 days but did not affect feed intake and feed conversion. Chicks from mature breeders had higher liveweight, weight gain and feed intake than those from young breeders in the first week, but feed conversion was not affected. Viability of chicks during the first week was not affected by any factor. No significant interaction among factors was observed for all variables. The advantage of feeding crumbled diets during the first week was evident for liveweight and weight gain at 42 days of age and the interaction of physical form and breeder age indicated that the advantage was greater for broilers from young breeders (143g) than from mature breeders (64g) when chicks were fed crumbled diet. Feed conversion to 42 days of age was improved when crumbled diets were supplied to chicks from young breeders (1.685 vs.1.718), but not do those from mature breeders (1.693 vs. 1.694). Total feed intake was higher when chicks received the vegetal pre-starter diet compared to that containing animal origin ingredients, but liveweight, weight gain and feed conversion were not affected. Birds from mature breeders had greater feed intake in the overall period. Feed conversion was not affected by type of ingredients of pre-starter diet. The factors studied did not influence the viability of the broilers to 42 days of age. It was concluded that crumbled feed in the pre-starter period improves the overall performance of chickens and the advantage is greater when fed to small chicks. All-vegetal diet in the pre-starter period is not detrimental to chicken performance.
92

Comparative breeding ecology in arctic-geese of different body size : an example in ross's and lesser snow geese

Traylor, Joshua James 02 July 2010
Two closely-related, different-sized species of geese nest sympatrically south of the Queen Maud Gulf (QMG) in Canadas central arctic. Following a period of high population growth rate in both species within the QMG, the population growth rate of larger-bodied lesser snow geese (Chen caerulescens caerulescens; hereafter snow geese) has slowed most recently to roughly half that observed in smaller-bodied Rosss geese (Chen rossii). I focused on factors that influence productivity and recruitment in these two species, to improve our understanding of life history variation associated with interspecific differences in body size, and to test for density-dependent population responses. I used long-term data (1991 to 2008) to compare spring nutrient reserves, breeding strategies, clutch sizes, nest success, and juvenile survival in Rosss and snow geese breeding at Karrak Lake, Nunavut; a large breeding colony located within the QMG.<p> Long-term patterns of spring body condition (i.e., fat and protein reserves) diverged in prospective breeding female Rosss and snow geese implying that differences in food acquisition ability had become more acute. Snow geese displayed larger reductions in protein and fat reserves through time compared to Rosss geese thereby suggesting a differential density-dependent response in the ability to store nutrient reserves, a prerequisite for breeding in both species. Decreased per capita food availability influenced the timing of reproduction in both species. Nesting phenologies of Rosss and snow geese, adjusted for variation in phenology of local spring climate, have become later by 6.5 and 5.0 days, respectively, since 1991. Nutritional strategies (i.e., reliance on reserves versus local food) used for clutch formation differed between species. Rosss geese displayed greater reliance on stored reserves (i.e., capital breeding) than did snow geese, though both used endogenous reserves (> 62% of yolk protein, > 48% of albumen, and > 73% of yolk lipid) for clutch formation. Rosss and snow geese experienced declines of 28% and 23% in body masses from arrival to post-laying and also until hatch demonstrating that endogenous reserves are the main nutrient sources for incubation. Still, constraints of small size forced Rosss geese to use a mixture of local food plants and reserves for incubation metabolism.<p> I then examined differences in clutch size, nest success, and juvenile survival to understand of the role of recruitment in the interspecific divergence of population trajectories. I did not find strong interspecific differences in clutch size and nest success. Overall, snow geese had a larger mean clutch size, which was expected based on benefits of a larger-body size. Clutch sizes decreased with delays in breeding and decreasing protein reserves of arriving females, although Rosss geese displayed larger declines with decreasing protein reserves. Mean apparent nest success for Rosss geese was 4.5% higher compared to snow geese. Nest success showed large declines (11%) in both species with increasing population size at the breeding colony. However, nest success of snow geese decreased twice as fast with delays in breeding compared to Rosss geese. Last, I found no evidence of negative density dependence in juvenile survival over time. Juvenile survival was higher in snow geese (48%) compared to Rosss geese (38%), consistent with a life history prediction based on body size differences. Despite lower juvenile survival, recruitment by Rosss geese is likely greater than that of snow geese because of earlier sexual maturity, higher breeding probability and/or greater nest success.<p> Ultimately, small body size of Rosss geese may produce an ideal life history schedule under resource limitation at this colony i.e., one that maximizes fitness compared to larger snow geese. Life history characteristics of Rosss geese (e.g., absolutely lower energy requirement, have a flexible breeding strategy, higher reproductive effort, an earlier age of sexual maturity, a shorter breeding cycle allowing delayed arrival and nest initiation on arctic breeding areas, and shorter time required by goslings to attain adult size), in addition to their smaller bill morphology may allow exploitation of a wider niche space (i.e., one that includes marginal quality and low quantity vegetation) relative to snow geese. Because there were no large differences in components of recruitment considered here, other components of recruitment (age of sexual maturity, breeding probability) may be affected more strongly by diminished spring nutrition in snow geese and thus have a larger influence on local population dynamics.
93

Comparative breeding ecology in arctic-geese of different body size : an example in ross's and lesser snow geese

Traylor, Joshua James 02 July 2010 (has links)
Two closely-related, different-sized species of geese nest sympatrically south of the Queen Maud Gulf (QMG) in Canadas central arctic. Following a period of high population growth rate in both species within the QMG, the population growth rate of larger-bodied lesser snow geese (Chen caerulescens caerulescens; hereafter snow geese) has slowed most recently to roughly half that observed in smaller-bodied Rosss geese (Chen rossii). I focused on factors that influence productivity and recruitment in these two species, to improve our understanding of life history variation associated with interspecific differences in body size, and to test for density-dependent population responses. I used long-term data (1991 to 2008) to compare spring nutrient reserves, breeding strategies, clutch sizes, nest success, and juvenile survival in Rosss and snow geese breeding at Karrak Lake, Nunavut; a large breeding colony located within the QMG.<p> Long-term patterns of spring body condition (i.e., fat and protein reserves) diverged in prospective breeding female Rosss and snow geese implying that differences in food acquisition ability had become more acute. Snow geese displayed larger reductions in protein and fat reserves through time compared to Rosss geese thereby suggesting a differential density-dependent response in the ability to store nutrient reserves, a prerequisite for breeding in both species. Decreased per capita food availability influenced the timing of reproduction in both species. Nesting phenologies of Rosss and snow geese, adjusted for variation in phenology of local spring climate, have become later by 6.5 and 5.0 days, respectively, since 1991. Nutritional strategies (i.e., reliance on reserves versus local food) used for clutch formation differed between species. Rosss geese displayed greater reliance on stored reserves (i.e., capital breeding) than did snow geese, though both used endogenous reserves (> 62% of yolk protein, > 48% of albumen, and > 73% of yolk lipid) for clutch formation. Rosss and snow geese experienced declines of 28% and 23% in body masses from arrival to post-laying and also until hatch demonstrating that endogenous reserves are the main nutrient sources for incubation. Still, constraints of small size forced Rosss geese to use a mixture of local food plants and reserves for incubation metabolism.<p> I then examined differences in clutch size, nest success, and juvenile survival to understand of the role of recruitment in the interspecific divergence of population trajectories. I did not find strong interspecific differences in clutch size and nest success. Overall, snow geese had a larger mean clutch size, which was expected based on benefits of a larger-body size. Clutch sizes decreased with delays in breeding and decreasing protein reserves of arriving females, although Rosss geese displayed larger declines with decreasing protein reserves. Mean apparent nest success for Rosss geese was 4.5% higher compared to snow geese. Nest success showed large declines (11%) in both species with increasing population size at the breeding colony. However, nest success of snow geese decreased twice as fast with delays in breeding compared to Rosss geese. Last, I found no evidence of negative density dependence in juvenile survival over time. Juvenile survival was higher in snow geese (48%) compared to Rosss geese (38%), consistent with a life history prediction based on body size differences. Despite lower juvenile survival, recruitment by Rosss geese is likely greater than that of snow geese because of earlier sexual maturity, higher breeding probability and/or greater nest success.<p> Ultimately, small body size of Rosss geese may produce an ideal life history schedule under resource limitation at this colony i.e., one that maximizes fitness compared to larger snow geese. Life history characteristics of Rosss geese (e.g., absolutely lower energy requirement, have a flexible breeding strategy, higher reproductive effort, an earlier age of sexual maturity, a shorter breeding cycle allowing delayed arrival and nest initiation on arctic breeding areas, and shorter time required by goslings to attain adult size), in addition to their smaller bill morphology may allow exploitation of a wider niche space (i.e., one that includes marginal quality and low quantity vegetation) relative to snow geese. Because there were no large differences in components of recruitment considered here, other components of recruitment (age of sexual maturity, breeding probability) may be affected more strongly by diminished spring nutrition in snow geese and thus have a larger influence on local population dynamics.
94

Variation in individual life-history trajectories and its consequence on population dynamics : the case of roe deer

Plard, Floriane 06 March 2014 (has links) (PDF)
Roe deer give birth each year in May. At each reproductive event, a female can be in different reproductive statuses: breeder or non breeder and can wean a variable number of offspring. The successive transitions between the different statuses of a given female give its individual reproductive trajectory. The performance of a given trajectory is assessed by its fitness which can be approximated by the total number of offspring weaned during the trajectory. Different individual life-history trajectories can exist in a same population and these different trajectories can reach similar or different fitness. This suggests that different strategies can be chosen by different individuals to reach the same fitness but also that individuals of high quality can reach higher fitness than individuals of low quality. The study of a roe deer population located in North-Eastern France allowed analyzing the sources and the consequences of individual heterogeneity on individual life-history trajectories and on population dynamics. This work showed that roe deer individual reproductive trajectories are consistent for a given female such as high quality females have an annual reproductive success higher than low-quality females. Female quality is partly generated by birth condition such as birth date and environmental conditions at birth. Individual life-history trajectories vary also randomly in relation to annual environmental conditions. In particular, climate change led to a decline in annual mean reproductive success and a decrease of the population growth rate in the last decades in relation to an increase of the mismatch between vegetation phenology and roe deer birth period. This work discussed how individual heterogeneity is generated in a long-lived species and how it influences individual life-history strategies and population dynamics
95

Alterações de parâmetros fisológicos e imunológicos em matrizes de frangos de corte vacinadas ou não contra a bronquite infecciosa das galinhas submetidas a diferentes períodos de jejum pós-eclosão

Fernandez Alarcon, Miguel Frederico [UNESP] 04 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-04Bitstream added on 2014-06-13T18:57:30Z : No. of bitstreams: 1 alarcon_mff_me_jabo.pdf: 1406127 bytes, checksum: 842dbbaa540dbb4b860fec0374842606 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Foram avaliados parâmetros fisiológicos e imunológicos de matrizes de corte vacinadas ou não contra o vírus da bronquite infecciosa das galinhas (VBIG), submetidas a diferentes períodos de jejum após a eclosão, seguido de alimentação até a terceira semana de vida. No Capítulo 2, encontram-se os resultados do desempenho zootécnico e o desenvolvimento de órgãos gastrintestinais. No Capítulo 3, estão descritos os resultados de parâmetros hematológicos e bioquímicos. O Capítulo 4 apresenta as cinéticas de decaimento dos anticorpos maternos e os perfis cinéticos da reposta imune humoral nos compartimentos local e sistêmico. A vacina contra a BIG influenciou parâmetros de desempenho, de morfometria intestinal, o hematócrito, parâmetros bioquímicos, percentuais de heterófilos e linfócitos e induziu a resposta imune humoral na secreção lacrimal. O jejum pós-eclosão prolongado seguido de alimentação influenciou negativamente o desempenho, o desenvolvimento das vísceras gastrintestinais, as variáveis bioquímicas, imunológicas e a maioria das variáveis hematológicas. Os dados indicam que períodos de jejum pós-eclosão superiores a 48 h devem ser evitados, pois ao afetar negativamente parâmetros hematológicos, intestinais e imunológicos, podem comprometer o crescimento das matrizes e inferir negativamente sobre sua resposta imune. No entanto, o jejum moderado pode favorecer a resposta imune vacinal / Immunological and physiological parameters were evaluated in broiler breeder vaccinated or not against infectious bronchitis virus (IBV), submitted to different periods of fasting post-hatching, followed by feed until the third week of life. In Chapter 2, are the results of zootechnical performance and development of gastrointestinal organs. The Chapter 3 describes the results of hematological and biochemical parameters of blood. Chapter 4 presents the kinetics of decay of maternal antibodies and the kinetic profiles of humoral immune response in local and systemic compartments. The IBV vaccine influenced parameters of performance, intestinal morphology, hematocrit, biochemical parameters, percentage of heterophils and lymphocytes, and induced humoral immune response in tear secretion. Prolonged fasting post-hatching, followed by feeding, negatively affected the performance, the development of gastrointestinal organs, biochemical variables, immunological and the most of hematological variables. The data indicate that periods of fasting post-hatching over 48 h should be avoided as they adversely affect the hematological, gastrointestinal and immunologic, may compromise the growth of broiler breeder and infer a negative effect on their immune response. However, moderate fasting can promote the immune response vaccine
96

Efeito do tipo e da forma física da ração pré-inicial e da idade das matrizes sobre o desempenho de frangos de corte / Effects of ingredient composition and processing of pre-starter diet and age of the breeders on the perfomance of chicks and broilers

Rejane Amaral 20 January 2006 (has links)
O objetivo deste estudo foi avaliar os efeitos da idade de matriz, composição e forma física da dieta pré-inicial (fornecida à base de 200 g por ave) na performance de frangos de corte machos até os 42 dias de idade. Os tratamentos consistiram das combinações de 2 tipos de ração pré-inicial: formuladas com ingredientes de origem vegetal (milho, farelo de soja e soja integral) ou com subprodutos de origem animal (farinha de carne e ossos, farinha de sangue); 2 formas físicas: farelada ou desintegrada e 2 idades de matrizes: jovem (32 semanas) ou adulta (55 semanas), num arranjo fatorial 2x2x2. O experimento foi realizado com 4 repetições de 45 aves, em blocos casualizados. Seguindo-se os tratamentos dietéticos na fase pré-inicial, todas as aves passaram a receber uma ração comum nas fases inicial, crescimento e final. A ração desintegrada no período pré-inicial resultou em maior peso vivo, ganho de peso, consumo de ração e conversão alimentar aos 7 dias de idade em comparação à ração farelada. A inclusão de ingredientes de origem animal nas dietas pré-iniciais resultou em um decréscimo de peso vivo e ganho de peso aos 7 dias de idade, mas não afetou o consumo de ração e a conversão alimentar. Pintos provenientes de matrizes adultas apresentaram maior peso vivo, ganho de peso e consumo de ração quando comparados àqueles provenientes de matrizes jovens na primeira semana de vida, mas a conversão alimentar não foi afetada. A viabilidade dos pintos na primeira semana não foi afetada por nenhum fator. Na primeira semana não foi observada nenhuma interação significativa entre os fatores para as variáveis. A vantagem da dieta desintegrada durante a primeira semana foi evidente para peso vivo e ganho de peso até os 42 dias de idade e a interação entre forma física e idade da matriz indicou uma vantagem para os frangos provenientes de matrizes jovens (143g) em relação àqueles provenientes de matrizes adultas (64g) quando a ração desintegrada foi fornecida. A conversão alimentar aos 42 dias de idade foi melhor quando a dieta desintegrada foi oferecida para pintos provenientes de matrizes jovens (1,685 vs. 1,718), mas não para aqueles provenientes de matrizes adultas (1,693 vs. 1,694). O consumo de ração total foi maior quando as aves receberam ração pré-inicial vegetal do que contendo ingredientes de origem animal, mas o peso vivo, ganho de peso e conversão alimentar não foram afetados. Aves provenientes de matrizes adultas apresentaram maior consumo de ração durante todo o período. A conversão alimentar não foi afetada pelo tipo de ingrediente utilizado na dieta pré-inicial. Os fatores estudados não influenciaram a viabilidade dos frangos até os 42 dias de idade. Conclui-se que a dieta desintegrada no período pré-inicial melhorou a performance de frangos e esta vantagem foi maior para pintos leves. A dieta vegetal no período pré-inicial não causou prejuízo à performance dos frangos. / The purpose of this study was to evaluate the effects of breeder age, composition and physical form of the pre-starter diet (supplied at a rate of 200 g per bird) the male broilers performance up to 42 days of age. The treatments consisted of the combinations of 2 types of prestarter diets: formulated to contain vegetal ingredients (corn, soybean meal, full fat soybean) or including animal ingredients (meat and bone meal, blood meal); 2 physical forms: mashed or crumbled; 2 breeder ages: young breeders (32 weeks old) or mature breeders (55 weeks old) in a 2X2X2 factorial arrangement. The experiment was carried out on 4 replicates of 45 birds, in a completely randomized block design. After receiving the dietary treatments in the pre-starter period all birds were given a common starter, growing and finishing diet. Crumbled feed in the pre-starter period resulted in improved liveweight, weight gain, feed intake and feed conversion up to 7 days of age compared to mashed feed. The inclusion of animal ingredients into the prestarter diets decreased liveweight and weight gain up to the age of 7 days but did not affect feed intake and feed conversion. Chicks from mature breeders had higher liveweight, weight gain and feed intake than those from young breeders in the first week, but feed conversion was not affected. Viability of chicks during the first week was not affected by any factor. No significant interaction among factors was observed for all variables. The advantage of feeding crumbled diets during the first week was evident for liveweight and weight gain at 42 days of age and the interaction of physical form and breeder age indicated that the advantage was greater for broilers from young breeders (143g) than from mature breeders (64g) when chicks were fed crumbled diet. Feed conversion to 42 days of age was improved when crumbled diets were supplied to chicks from young breeders (1.685 vs.1.718), but not do those from mature breeders (1.693 vs. 1.694). Total feed intake was higher when chicks received the vegetal pre-starter diet compared to that containing animal origin ingredients, but liveweight, weight gain and feed conversion were not affected. Birds from mature breeders had greater feed intake in the overall period. Feed conversion was not affected by type of ingredients of pre-starter diet. The factors studied did not influence the viability of the broilers to 42 days of age. It was concluded that crumbled feed in the pre-starter period improves the overall performance of chickens and the advantage is greater when fed to small chicks. All-vegetal diet in the pre-starter period is not detrimental to chicken performance.
97

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%
98

Idade da matriz e período de armazenamento de ovos incubáveis no rendimento de incubação e desempenho inicial de poedeiras comerciais / Breeder hen ages and the storage period of the eggs over the incubation efficiency and starter performance

TANURE, Candice Bergmann Garcia e Silva 21 May 2008 (has links)
Made available in DSpace on 2014-07-29T15:07:49Z (GMT). No. of bitstreams: 1 Dissertacao_CBGSTANURE.pdf: 173355 bytes, checksum: b5dad268631980af0fc582bf4351c9c3 (MD5) Previous issue date: 2008-05-21 / Two experiments have been carried out to evaluate the effect of the breeder hen ages and of the storage period of the eggs over the incubation efficiency and initial performance of laying hens. In the first experimental phase, 7224 Dekalb eggs with 32 and 57 weeks old, were incubated with three, five and seven days of storage. The treatments were defined according to the breeder hens ages and their period of storage of eggs, summing up to six treatments with fourteen repetitions of treatment each. The statistical outline was random and the tray height was a covariable. The efficiency of the incubation, the eggs loss of weight during storage, the quality of incubated eggs and the absolute weight of the yolk sac in relation to the weight of the chicken was evaluated. On the second experimental phase, 600 chickens from the six treatments of the first experimental phase were used. The poultry were bred up to the 28th day of life in common batteries. The statistical outline was totally random, and the height of the batteries was a covariable, with five repetitions of twelve birds in each treatment. The starter performance of chicks (up to 28 days of life) was evaluated. The results were submitted to variance analysis and to verify the importance of differences between the average of treatments, the Tukey test was used, with a probability of 5%. The breeder hens of 57 weeks produce heavier eggs with a larger quantity of albumen and yolk. The old breeder hens eggs had a lower quality of albumen when stored for seven days. The loss of weight of the eggs during storage and removal was higher according to the aging of the breeder hen. Eggs produced by the young breeder hens had a higher hatching rate; however, no matter the age of the breeder hen, there was a decrease of the hatching rate of fertile eggs whenever the storage period was increased. The breeder hens with 57 weeks produced heavier chicks and lower chick/egg weight coefficient. The higher ratio yolk sac/chick weight was obtained by the eggs produced by the old breeder hens. There was a lower weight loss of chicks from young breeder hens during the removal of incubatory trays to the grange. The storage period did not interfere in the birds performance and birds from old matrixes presented worse uniformity, higher final weight and bigger food allowance / Foram conduzidos dois experimentos para avaliar o efeito da idade das matrizes leves e o período de armazenamento dos ovos no rendimento de incubação e desempenho inicial de poedeiras comerciais. Com relação à primeira fase experimental, foram utilizados 7.224 ovos da linhagem Dekalb com 32 e 57 semanas de idade, incubados com três, cinco e sete dias de armazenamento. Os tratamentos foram definidos pelas idades das matrizes e o período de armazenamento dos ovos, totalizando seis tratamentos com 14 repetições por tratamento. O delineamento estatístico foi inteiramente ao acaso, sendo a altura da bandeja uma covariável. Avaliou-se o rendimento da incubação, a perda de peso dos ovos no armazenamento, a qualidade dos ovos incubáveis e o peso absoluto do saco vitelino em relação ao peso do pinto. Já na segunda fase experimental, foram utilizados 600 pintos provenientes dos seis tratamentos da fase experimental um. As aves foram criadas até os 28 dias de vida em baterias coletivas. O delineamento estatístico foi inteiramente ao acaso, e a altura da bateria considerada uma covariável, com cinco repetições de 12 aves em cada tratamento. Avaliou-se o desempenho inicial (até 28 dias de idade) das pintainhas. Os resultados foram submetidos à análise de variância e para verificar a significância das diferenças entre as médias dos tratamentos foi aplicado o teste de Tukey a 5% de probabilidade. Foi observado que matrizes com 57 semanas de idade produzem ovos com maior peso, conteúdo e gema. Ovos de matrizes velhas apresentam pior qualidade de albúmen quando armazenados por sete dias. A perda de peso dos ovos durante o armazenamento e na transferência aumentou de acordo com o avançar da idade da matriz. Ovos produzidos pelas matrizes novas obtiveram melhor taxa de eclosão, entretanto, independente da idade da matriz, à medida que aumentou o período de armazenamento houve diminuição na taxa de eclosão dos ovos férteis. As matrizes com 57 semanas de idade produziram pintos mais pesados e menor relação peso do pinto/peso do ovo. A maior relação saco vitelino/peso do pinto foi obtida pelos ovos produzidos pelas matrizes velhas. Houve menor perda de peso no deslocamento do incubatório à granja pelos pintos oriundos de matrizes novas. O período de armazenamento dos ovos não interferiu no desempenho, e aves provindas de matrizes velhas apresentaram pior uniformidade e maior peso final e consumo de ração
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Suplementação de ácido linoleico conjugado na dieta de matrizes de frango de corte e da sua progênie / Supplementation of conjugated linoleic acid in the diet of broiler breeders and of their progeny

Martins, Poliana Carneiro 26 September 2017 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2017-10-16T10:47:22Z No. of bitstreams: 2 Tese - Poliana Carneiro Martins - 2017.pdf: 2303821 bytes, checksum: 3e74a5fc40c60b212e0c79f9270d5b43 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-10-16T10:47:41Z (GMT) No. of bitstreams: 2 Tese - Poliana Carneiro Martins - 2017.pdf: 2303821 bytes, checksum: 3e74a5fc40c60b212e0c79f9270d5b43 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-10-16T10:47:41Z (GMT). No. of bitstreams: 2 Tese - Poliana Carneiro Martins - 2017.pdf: 2303821 bytes, checksum: 3e74a5fc40c60b212e0c79f9270d5b43 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-09-26 / Two experiments were carried on to evaluate the effects of the inclusion of conjugated linoleic acid (CLA) on the diets of breeders and broilers, and the alterations caused by post-hatch fasting. In the first experiment, two commercial flocks of breeders aged 58 weeks old were used, and one of them was supplemented for 26 days with 0.025% CLA. At the end of the supplementation, a completely randomized design was applied, composed by two treatments (0 and 0.025% CLA), to evaluate the physical quality and composition of the eggs. Subsequently, 270 eggs per treatment were distributed in two hatcheries, in a randomized block design, determined according to the hatchery used. The incubation parameters were evaluated and the fatty acid profile of the feed, yolk and yolk sac were determined. After hatching, post-hatching diets (0 or 0.025% CLA) were provided for 12 hours, and 320 chicks were housed in a completely randomized design, in a 2x2 scheme (maternal CLA x post-hatching CLA), totalizing four treatments and eight replicates of 10 birds each. The organs relative weight, intestinal development and humoral and cellular immunity were evaluated in embryos, newly hatched chicks, 12 hours after hatching, and at seven days old, as the pre-starter performance. The inclusion of CLA in the diet was able to alter the physical and bromatological characteristics of the eggs and yolk sacs of the progeny from supplemented breeders, also changing the fatty acid profile, but without causing embryonic mortality. The intestine was also influenced by CLA, both macroscopically and histologically. The CLA offered to the breeders influenced the intestinal development of the chicks from the embryonic phase and continued to exert effect after hatching, associated with the progeny supplementation. Breeder supplementation led to a better pre-starter performance of the progeny. In the second experiment, 320 male and female chicks were distributed in a completely randomized design, in a 2x2 factorial scheme, considering post-hatch fasting (access to water for 12 hours; access to water and food for 12 hours) and post-hatch diet (0; 0.025% CLA). The birds were vaccinated at 15 days old against Newcastle disease virus. The metabolizability of diets from four to seven days old, intestinal and organs development, and cellular and humoral immunity were evaluated weekly up to 35 days old. Post-hatch fasting affected performance, and CLA was not able to minimize the negative effects of fasting. However, birds were able to recover up to 35 days old. Post-hatch fasting decreased the immune response of birds. In both assays, CLA generally positively influenced humoral and cellular immunity. Among the evaluated organs, the liver was the main one to have its relative weight altered due to the use of CLA. Supplementing only progeny did not provide as much benefit as compared to supplementation of the breeder or both. The obtained results demonstrate the inclusion level of 0.025% of CLA is safe for use in breeders and may bring benefits to their progeny. / Foram conduzidos dois experimentos para avaliar os efeitos da inclusão de ácido linoleico conjugado (CLA) na dieta de matrizes e frangos de corte, e as alterações causadas pelo jejum pós-eclosão. No primeiro experimento, foram acompanhados dois lotes de matrizes com 58 semanas de idade, sendo um suplementado 26 dias com 0,025% de CLA. Ao final da suplementação, adotou-se o delineamento inteiramente casualizado, composto por dois tratamentos (0 e 0,025% CLA), para avaliação da qualidade física e da composição dos ovos. Posteriormente, 270 ovos por tratamento foram distribuídos em duas incubadoras, aplicando-se o delineamento em blocos casualizados, determinados pela incubadora utilizada. Avaliaram-se os parâmetros de incubação e determinou-se o perfil de ácidos graxos da ração, gema e saco vitelínico. Após a eclosão, dietas pós-eclosão (0 ou 0,025% de CLA) foram fornecidas por 12 horas, e 320 pintos foram alojados em delineamento inteiramente casualizado e esquema 2x2 (CLA materno x CLA pós-eclosão), totalizando quatro tratamentos e oito repetições de 10 aves cada. Avaliou-se o peso relativo de órgãos, o desenvolvimento intestinal e a imunidade humoral e celular em embriões, neonatos, após 12 horas, e aos sete dias de idade, e o desempenho pré-inicial. A inclusão de CLA na dieta foi capaz de alterar características físicas e bromatológicas dos ovos e sacos vitelínicos da progênie de matrizes suplementadas, causando também alteração do perfil de ácidos graxos, porém sem provocar a morte dos embriões. O intestino também foi influenciado pelo CLA, tanto macroscopicamente, quanto a nível histológico. O CLA oferecido às matrizes influenciou o desenvolvimento intestinal dos pintos desde a fase embrionária e continuou a exercer efeito após a eclosão, aliado à suplementação conjunta da progênie. A suplementação da matriz garantiu melhor desempenho pré-inicial da progênie. No segundo experimento, 320 pintos machos e fêmeas foram distribuídos em delineamento inteiramente casualizado, em esquema fatorial 2x2, considerando os fatores jejum alimentar pós-eclosão (acesso à água por 12 horas; acesso à água e alimento por 12 horas) e a dieta pré-inicial (0; 0,025% de CLA). As aves foram vacinadas aos 15 dias de idade contra o vírus da doença de Newcastle. Avaliou-se a metabolizabilidade das dietas de quatro a sete dias de idade, e o desenvolvimento intestinal e dos órgãos, e a imunidade celular e humoral, semanalmente até os 35 dias de idade. O jejum pós-eclosão afetou o desempenho, e o CLA não foi capaz de minimizar os efeitos negativos do jejum. No entanto, as aves conseguiram se recuperar até os 35 dias de idade. O jejum pós-eclosão prejudicou a resposta imune das aves. Nos dois ensaios, de modo geral, o CLA influenciou positivamente a imunidade humoral e celular. Entre os órgãos avaliados, o fígado foi o principal a sofrer alterações em seu peso relativo em decorrência da utilização de CLA. A prática de suplementar apenas a progênie não trouxe tantos benefícios quando comparada à suplementação da matriz ou de ambos. Os resultados aqui obtidos demonstraram que o nível de inclusão de 0,025% de CLA é seguro para utilização em matrizes e pode trazer benefícios à progênie.
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Parní generátor reaktoru ESFR / The steam generator for ESFR reactor

Bátěk, David January 2012 (has links)
This master thesis deals steam generator for ESFR (European Sodium Fast Reactor), which is heated by liquid sodium. In the beginning chapters, there are theoretic information about ESFR's parameters and its' comparison with ohter types of heat exchangers in nuclear reactors with the same principal (sodium as a coolant). Then designing part follows, which contents of introduction of calculations, option of material and conception of heater. Computational part on its own includes thermal, hydraulic and stress calculations and comparison with aspects in nuclear safety and security.

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