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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.
1

The role of magnesium in egg shell formation and function

Waddell, A. L. January 1987 (has links)
No description available.
2

Desempenho e qualidade óssea de galinhas poedeiras tratadas com L-pidolato de cálcio® /

Nogueira, Henrique de Sousa. January 2017 (has links)
Orientador: Silvana Martinez Baraldi Artoni / Coorientador: Edney Pereira da Silva / Banca: Nilce Maria Soares / Banca: Lizandra Amoroso / Resumo: Para se conseguir alcançar a crescente demanda de ovos comercial é necessário entender os fatores responsáveis na produção desse produto. Assim o desempenho produtivo tal como a qualidade dos ovos e as condições fisiológicas da ave são muito relevantes para tal objetivo. O presente trabalho teve como objetivo, avaliar a eficácia do L - pidolato de cálcio®, precursor de dois aminoácidos (prolina e arginina) que estão presentes na constituição da membrana interna do ovo e ossos, sobre o desempenho produtivo e sobre a qualidade de ovos bem como a qualidade óssea de galinhas poedeiras Hy-line W36 no período de 56 a 69 semanas de idade. O trabalho foi conduzido no Laboratório de Ciências Avícolas (LAVINESP), do departamento de Zootecnia da UNESP- FCAV, Câmpus de Jaboticabal no período de novembro de 2016 a fevereiro de 2017. Foram testados 10 tratamentos compostos de duas dietas e 5 níveis de L - pidolato de cálcio®, resultando assim um esquema fatorial cruzado 2×5, com oito repetições de seis aves cada, totalizando unidades experimentais e um total de 480 aves. Foram utilizados quatro blocos, com duas repetições por bloco, constituídos de faixas de peso. As medidas foram realizadas sobre as mesmas unidades experimentais durante 13 semanas, totalizando 91 dias de ensaio. Não foi possível observar nas medidas avaliadas um nível exato para que se obtenha o melhor resultado em todas elas. No entanto, apresentou efeito das dietas formuladas com grande frequência, durante o período ava... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: To achieve a growing demand for commercial eggs, it is necessary to understand the factors of production in the production of the product. Thus, productive performance as a quality of eggs and as physiological conditions of the bird are very relevant to the objective. The L - pidolato calcium®, a precursor of two amino acids (proline and arginine) are present in the constitution of the inner membrane of the egg and bones, on the productive performance and on the quality of eggs as well as a bone quality of laying hens Hy-line W36 in the from 56 to 69 weeks of age. The work was conducted at the Laboratory of Poultry Sciences (LAVINESP), Department of Zootechnics of UNESP-FCAV, Campus of Jaboticabal in the period of November 2016, February 2017. Ten treatments were tested, composed of two diets and five levels of L-pidolate of calcium®, resulting in a 2 × 5 cross factorial scheme, with eight replicates of six birds each, totaling experimental units and a total of 480 birds. Four blocks were used, with two replicates per block, consisting of weight bands. Measurements were performed on the same experimental units for 13 weeks, totaling 91 days of testing. It was not possible to observe the measures evaluated, exist to obtain the best result in all of them. However, the formulated diets were presented with great frequency during the period evaluated. This can be observed in measures of feed intake, bark resistance, Haugh unit, albumen weight, bone mineral content, bone strength, tibiotarsus length, tibiotarsus weight and Seedor index. A 30% reduction in arginine in the diet affected the performance of poultry. This research supports the recommendation of 150 g of L-pidolate of calcium® per ton of feed for improved resistance and egg shell weight. / Mestre
3

Microbial infection of avian eggs : a threat to all synchronously incubating species? Case study of New Zealand's little blue penguin (Eudyptula minor) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Auckland, New Zealand

Boyer, Anne-Sophie January 2010 (has links)
Microbial infection of eggs was originally investigated in terms of human health only. Recently, however, it was found that it can also cause early embryo mortality in birds, mainly through trans-shell infection prior to incubation. Trans-shell infection is highly dependent upon environmental conditions, egg temperature and egg properties such as shell quality and antimicrobial defences. Microbial infection of eggs is more likely to occur in synchronously incubating species as first laid eggs can be exposed for up to several days prior to full incubation. One example of a population that seems at particular risk of egg microbial infection is New Zealand’s little blue penguin (Eudyptula minor) from Tiritiri Matangi Island. This bird lays two eggs on average three days apart, and is believed to begin full incubation only after the second egg has been laid. Both eggs are laid in particularly humid and soiled nests and contain only low levels of lysozyme, an important antimicrobial protein. The aims of this study were therefore to 1) obtain a first examination of the rates of shell and trans-shell microbial infection of chicken eggs in New Zealand and assess the effects of cleaning on those rates, 2) investigate the role of microbes in hatching failure of little blue penguin eggs and 3) investigate other factors affecting little blue penguin egg viability. This study revealed that shell infection in chicken eggs significantly increased with exposure and significantly decreased with cleaning; however, trans-shell infection was only marginally affected by exposure and cleaning. On Tiritiri Matangi Island, Hauraki Gulf, New Zealand, nest type, egg order and shell cleaning did not affect hatching success, suggesting that nest conditions and microbial infection prior to incubation were not a major cause of egg mortality in this population. Temporary abandonment during incubation, however, was very frequent in the second half of the breeding season and fatal to most eggs. These temporary abandonments seemed to be caused by resource limitations, an aspect that should be investigated in future studies.
4

Effects on the reproductive system in domestic fowl (Gallus domesticus) after embryonic exposure to estrogenic substances /

Hermansson, Alexandra, January 2007 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.
5

Monitoramento e avaliação dos ovos férteis de avestruz submetidos à incubação artificial

Sabino, Neide Silva Coelho [UNESP] 05 March 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-03-05Bitstream added on 2014-06-13T20:56:06Z : No. of bitstreams: 1 sabino_nsc_me_araca.pdf: 202070 bytes, checksum: 6ec90b3bae49b1d0f452bd855b8ca174 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A desidratação dos ovos de avestruz (Struthio camelus) na incubação artificial é a principal causa do desenvolvimento e qualidade do filhote. Neste estudo, a necessidade de avaliar e manejar os ovos durante a incubação, tornou-se evidente. No incubatório das instalações do Setor Experimental de Zootecnia (SEZ) – UNESP/Araçatuba-SP, foram utilizados 129 ovos férteis eclodidos e 70 ovos férteis não eclodidos para a avaliação da perda de água aos 38 dias; as características da casca, a porosidade e a espessura foram confrontadas à perda total de água do ovo. Observou-se uma diferença na perda total de água para ovos férteis eclodidos (15,45%) e ovos férteis não eclodidos (10,45%). Foram estudados 1303 ovos férteis eclodidos quanto ao posicionamento na incubadora e à desidratação. Para a obtenção dos resultados, a incubadora foi estratificada em 7 prateleiras, 8 gavetas e 3 profundidades. Verificou-se uma perda maior de água por evaporação, quando os ovos estavam localizados nas gavetas próximas ao aquecedor e à entrada de ar desumidificado. Porém, não foram detectadas alterações provocadas pela altura da prateleira ou mesmo pela proximidade dos ovos em relação à porta ou ao fundo da incubadora. Desta forma, concluiu-se que a avaliação e o manejo dos ovos de avestruz na incubação artificial devem fazer parte do controle diário do incubatório. / The dehydration of eggs of ostrich (Struthio camelus) in the artificial incubation is the main cause of the development and quality of the youngling. In this study, the necessity to evaluate and to handling eggs during the incubation, became evident. In the room incubation of the installations of the Experimental Zootechny Sector (EZS) - UNESP/Araçatuba- São Paulo, Brazil, 129 ecloded fertile eggs and 70 fertile not ecloded eggs was been followed for the evaluation of the loss of water to 38 days and samples randomly of rinds was collated the characteristics of the rind, porosity and thickness, to the total loss of water of the egg. A difference observed in the total loss of water for ecloded fertile eggs was (15.45%) and fertile not ecloded eggs was (10.45%). Studied of 1303 ecloded fertile eggs how much to the positioning in the incubator and the dehydration for the attainment of the results, the incubator was subdivided in seven shelves, eight drawers and three depths. A bigger loss for evaporation of eggs was verified, when located in the drawers next to the heater and the dry air entrance. Nevertheless, no effect related to the shelves height was detected, not even when the proximity of the egg to the incubator door or the deep one was concerned. In such a way, one concluded that the evaluation and the handling of eggs of ostrich in the artificial incubation must be part of the daily control of the room incubation.
6

Monitoramento e avaliação dos ovos férteis de avestruz submetidos à incubação artificial /

Sabino, Neide Silva Coelho. January 2009 (has links)
Orientador: Manoel Garcia Neto / Banca: Antonio Carlos de Laurentiz / Banca: Max José de Araújo Faria Júnior / Resumo: A desidratação dos ovos de avestruz (Struthio camelus) na incubação artificial é a principal causa do desenvolvimento e qualidade do filhote. Neste estudo, a necessidade de avaliar e manejar os ovos durante a incubação, tornou-se evidente. No incubatório das instalações do Setor Experimental de Zootecnia (SEZ) - UNESP/Araçatuba-SP, foram utilizados 129 ovos férteis eclodidos e 70 ovos férteis não eclodidos para a avaliação da perda de água aos 38 dias; as características da casca, a porosidade e a espessura foram confrontadas à perda total de água do ovo. Observou-se uma diferença na perda total de água para ovos férteis eclodidos (15,45%) e ovos férteis não eclodidos (10,45%). Foram estudados 1303 ovos férteis eclodidos quanto ao posicionamento na incubadora e à desidratação. Para a obtenção dos resultados, a incubadora foi estratificada em 7 prateleiras, 8 gavetas e 3 profundidades. Verificou-se uma perda maior de água por evaporação, quando os ovos estavam localizados nas gavetas próximas ao aquecedor e à entrada de ar desumidificado. Porém, não foram detectadas alterações provocadas pela altura da prateleira ou mesmo pela proximidade dos ovos em relação à porta ou ao fundo da incubadora. Desta forma, concluiu-se que a avaliação e o manejo dos ovos de avestruz na incubação artificial devem fazer parte do controle diário do incubatório. / Abstract: The dehydration of eggs of ostrich (Struthio camelus) in the artificial incubation is the main cause of the development and quality of the youngling. In this study, the necessity to evaluate and to handling eggs during the incubation, became evident. In the room incubation of the installations of the Experimental Zootechny Sector (EZS) - UNESP/Araçatuba- São Paulo, Brazil, 129 ecloded fertile eggs and 70 fertile not ecloded eggs was been followed for the evaluation of the loss of water to 38 days and samples randomly of rinds was collated the characteristics of the rind, porosity and thickness, to the total loss of water of the egg. A difference observed in the total loss of water for ecloded fertile eggs was (15.45%) and fertile not ecloded eggs was (10.45%). Studied of 1303 ecloded fertile eggs how much to the positioning in the incubator and the dehydration for the attainment of the results, the incubator was subdivided in seven shelves, eight drawers and three depths. A bigger loss for evaporation of eggs was verified, when located in the drawers next to the heater and the dry air entrance. Nevertheless, no effect related to the shelves height was detected, not even when the proximity of the egg to the incubator door or the deep one was concerned. In such a way, one concluded that the evaluation and the handling of eggs of ostrich in the artificial incubation must be part of the daily control of the room incubation. / Mestre
7

Desempenho produtivo e qualidade de ovos de poedeiras alimentadas com diferentes fontes de cálcio / Productive performance and eggs quality of laying hens fed with different calcium sources

Lima, Hiagos Felipe Firmino de 23 February 2016 (has links)
Made available in DSpace on 2016-08-15T20:31:28Z (GMT). No. of bitstreams: 1 HiagosFFL_DISSERT.pdf: 794630 bytes, checksum: b9112529e3742dd0a6d9fbab5a1a63fa (MD5) Previous issue date: 2016-02-23 / In animal production, where food represents about 70% of the cost of production, the supply of calcium to participate in large numbers in feed formulations, become the use of mineral origin organic important to maximize animal performance and minimize costs. Taking up the importance of integrity and eggshell strength in the conservation of its nutritional and microbiological property that mean the product quality and food safety, these features become essential for the approval of the egg by the consumer market. The objective was to evaluate different sources of calcium in diets on growth performance and eggs quality of laying hens light. The cages are equipped with linear feeder in galvanized sheet and drinker type nipple. The birds were housed in shed screen, in masonry, with clay tile roof equipped with 120 metal cages (0,20m x 0,40m x 0,40m) galvanized wire provided sideboard eggs arranged in four rows with corridor central. We used 120 birds of Bankiva line in the initial laying phase, starting the experiment when animals were in egg production and body weight even, the experimental period was 22-34 weeks old and the birds distributed in a completely randomized design with four treatments. Each treatment had 10 repetitions with 3 birds each unit experimental and consisted of four experimental diets with different sources of calcium: limestone, búzio shell flour (Anomalocardia brasiliana), oyster shell flour (Crassostrea brasiliana) and egg shell flour. Were evaluated: egg production rate, feed intake, feed conversion, absolute and relative weight of yolk, albumen and shell, height and width of the egg, specific gravity, yolk color, eggshell thickness, Haugh unit, albumen and yolk index. Had no significant effect (P> 0.05) between the treatments, for performance variables, egg production rate had a significant effect (P <0.05), its worst result egg shell flour. The egg shell flour was the only treatment showed significantly (P <0.05) for the weight, height and width of the egg, specific gravity, height and width albumen yolk, yolk absolute weight, albumen and shell, relative weight of the albumen and shell thickness, with worse results compared to the other treatments. Therefore, limestone, búzio shell flour and oyster shell flour, can be used as a source of calcium for laying rations / Na produção animal, onde a alimentação representa cerca de 70% do custo de produção, o suprimento de cálcio por participar em grande quantidade nas formulações de rações, torna a utilização de minerais de origem orgânica importante para se maximizar o desempenho animal e minimizar os custos. Levando-se a importância da integridade e resistência da casca do ovo na conservação de sua propriedade nutricional e microbiológica que significam a qualidade do produto e segurança alimentar, estas características tornam-se essenciais para a aprovação do ovo por parte do mercado consumidor. Diante disso, objetivou-se avaliar diferentes fontes de cálcio em rações, no desempenho produtivo e qualidade de ovos de poedeiras de linhagem leves. As aves foram alojadas em galpão telado, em alvenaria, com cobertura de telha de barro equipado com 120 gaiolas metálicas (0,20m x 0,40m x 0,40m) de arame galvanizado providas de aparador de ovos, dispostas em quatro fileiras com corredor central. As gaiolas são equipadas com comedouro linear em chapa galvanizada e bebedouro do tipo nipple. Foram utilizadas 120 aves da linhagem Bankiva em fase inicial de postura, iniciando o experimento quando os animais estavam com produção de ovos e peso corporal uniforme, o período experimental compreendeu de 22 a 34 semanas de idade sendo as aves distribuídas em delineamento inteiramente ao acaso com quatro tratamentos. Cada tratamento composto por 10 repetições com 3 aves por unidade experimental e sendo constituídos por quatro rações experimentais, com diferentes fontes de cálcio: calcário calcítico, farinha de concha búzio (Anomalocardia brasiliana), farinha de concha de ostra (Crassostrea brasiliana) e farinha de casca de ovo. Foram avaliados: taxa de postura, consumo de ração, conversão alimentar, peso absoluto e relativo de gema, albúmen e casca, peso, altura e largura do ovo, gravidade específica, espessura de casca, unidade Haugh, índice de albúmen e de gema. Não foram significativas (P>0,05) entre os tratamentos estudados, as variáveis de desempenho, exceto taxa de postura, a qual obteve efeito significativo (P<0,05), tendo resultado inferior para o tratamento com a farinha de casca de ovo. A farinha de casca de ovo foi o único tratamento que apresentou efeito significativo (P<0,05), para as variáveis de peso, altura e largura do ovo, gravidade específica, altura da gema e largura do albúmen, peso absoluto de gema, albúmen e casca, peso relativo do albúmen e espessura de casca, apresentando resultados inferiores em comparação aos demais tratamentos. Portanto, o calcário calcítico, farinha de concha de búzio e farinha de concha de ostra, por apresentarem uma maior granulometria demonstrou melhores resultados, podendo ser utilizadas como fonte de cálcio em rações de poedeiras de linhagem leves

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