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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

Effect of housing environment and laying hen strain on performance, egg quality and bone properties as well as cloacal and eggshell microbiology

Sharma, Milan Kumar 01 May 2020 (has links)
Laying hen welfare is gaining importance in the United States and several states have passed legislation for a welfareriendly housing environment, which has forced the egg industry to explore alternative housing environments. For this reason, our first objective was to determine the effect of housing environment and laying hen strain on production performance and egg quality. Results showed that production performance of the hens raised in the alternative housing system was similar to the conventional system. The second objective was to compare the eggshell and cloacal microbiology. Our results indicated that the microbial load observed was higher in the alternative system compared to the conventional system. The third objective was to determine the effects of housing environment and laying hen strain on tibia and femur bone properties. The results demonstrated that the alternative system provided better tibia and femur bone characteristics, but it varied among laying hen strains.
92

Control of <i>Salmonella Enterica</i> serovar enteritidis in shell eggs by ozone, ultraviolet radiation, and heat

Rodriguez Romo, Luis Alberto 10 March 2004 (has links)
No description available.
93

Potential application areas for Fresenius Kabi's bonus products

Karlsson, Jenny, Brink, Matilda, Annala, Elina January 2019 (has links)
The main purpose of the project was to investigate existing markets within the food- and cosmetic industry in order to determine a strategy for market entrance with the bonus product of Fresenius Kabi. The original bonus product, P080, is a rest product from the process where phospholipids are extracted from egg yolk powder. P80 is a refine version of the P080 where egg yolk oil has been extracted, hence the protein content in P80 is higher. The extracted egg yolk oil is the final portion of the bonus product. Thereby, the original bonus product can be divided into two refined fractions. This project investigates the potential for each of these three substances to be a part of a fictive product.  By scanning the global protein market as well as the egg yolk protein and egg oil market, seven potential product segments were discovered. These segments were further evaluated in order to bring out specific products that were potential candidates as products based on the bonus product.  The analysis resulted in two fictive products based on P080; high value nutrition bars and snacks for seniors, one based on P80; protein powder, and one based on egg yolk oil; dietary supplement. All presented in three business cases.
94

Ozônio e radiação ultravioleta na higienização da casca de ovos comerciais /

Panini, Anselmo Rodrigo January 2019 (has links)
Orientador: Marcos Franke Pinto / Resumo: O Brasil é um dos maiores produtores de ovos do mundo e devido ao fato desse alimento estar cotidianamente na mesa do brasileiro, um controle contínuo e rigoroso deve ser desenvolvido a fim de garantir sua qualidade físico-química e microbiológica. Neste estudo foi avaliada a qualidade microbiológica e físico-química de ovos frescos submetidos a metodologias alternativas para desinfecção da casca. Foram realizadas diversas combinações de tratamentos, utilizando a lavagem dos ovos com água clorada e água ozonizada, e a exposição dos ovos ao gás ozônio e à radiação ultravioleta (UV), e foi avaliado seu efeito em comparação a ovos não higienizados. Após os tratamentos, os ovos foram submetidos à contagem total de microrganismos mesófilos aeróbios e facultativos viáveis e à contagem de coliformes a 30-35oC.Também foi avaliado o efeito dos tratamentos no comportamento dos parâmetros físico-químicos de qualidade dos ovos armazenados sob refrigeração e a temperatura ambiente. Todos os tratamentos foram eficazes na redução da contaminação microbiana da casca dos ovos. A exposição à luz U.V. e ao gás ozônio, sem lavagem prévia dos ovos, não diferiu dos tratamentos nos quais os ovos foram lavados com água clorada, que é o procedimento normalmente empregado na higienização dos ovos. A qualidade dos ovos durante o armazenamento abaixo de 4ºC e a 25ºC foi avaliada durante 28 dias por análises semanais de unidade Haugh, índice de gema, pH e pela perda de peso dos ovos. Não houve diferença ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Brazil is one of the largest egg producers in the world and because this food is daily in the table of the Brazilians, a continuous and rigorous control must be developed in order to guarantee its physical-chemical and microbiological quality. In this study, the microbiological and physicochemical quality of fresh eggs submitted to alternative methodologies for disinfecting the shell was evaluated. Several combinations of treatments were performed, using egg washing with chlorinated and ozonated water, and egg exposure to ozone gas and ultraviolet radiation (UV), and their effect was evaluated comparing with not sanitized eggs. After treatments, the eggs were submitted to total count of viable mesophilic aerobic and facultative microorganisms and 30-35oC coliforms count. The effect of the treatments on the behavior of physicochemical quality parameters of the eggs stored under refrigeration and at room temperature was also evaluated. All treatments were effective in reducing the microbial contamination of eggshell. The exposure of the eggs to U.V. and ozone gas, without previous washing, did not differ from the treatments in which the eggs were washed with chlorinated water, which is the normal procedure used in the hygiene of the eggs. Eggs quality during storage below 4°C and at 25°C was evaluated for 28 days by weekly Haugh unit, yolk index, pH and weight loss analyses. There was no significant difference between the treatments, but the temperature was determinant for egg ... (Complete abstract click electronic access below) / Mestre
95

Επίδραση της αλατότητας και του σταδίου ανάπτυξης στην πλευστότητα αυγών τσιπούρας (Sparus aurata, L. 1758) / The effect of salinity and stage of development on the buoyancy of eggs of gilthead seabream (Sparus aurata, L. 1758)

Λεονταρίτου, Παναγιώτα 28 June 2007 (has links)
Η τσιπούρα είναι ένα είδος με ιδιαίτερο εμπορικό ενδιαφέρον. Στην Ελλάδα η εκτροφή της είναι ιδιαίτερα σημαντική. Παρά τη μεγάλη μελέτη λόγω της εκτροφής του είδους, υπάρχουν ακόμα πολλά αναπάντητα ερωτήματα ειδικά σε θέματα της αναπαραγωγής. Η μελέτη που έγινε δίνει πληροφορίες σχετικά με την πλευστότητα αυγών τσιπούρας εκτροφής, προέλευσης Ατλαντικού και Μεσογείου, φυσικής και όψιμης φωτοπεριόδου, όπως αυτή διαμορφώνεται καθ’ όλη τη διάρκεια της αναπαραγωγικής περιόδου (4,5 μήνες) και σε 7 διαφορετικές αλατότητες (32, 33, 34, 35, 36, 37, 38 ppt). Η αλατότητα ωοτοκίας ήταν 40 ppt. Μετρήθηκαν επίσης οι διάμετροι των αυγών σε δύο από αυτές τις αλατότητες (32 και 35ppt). Τα αποτελέσματα έχουν ιδιαίτερο οικολογικό ενδιαφέρον, καθώς επιτρέπουν τη δόμηση κάποιων υποθέσεων σχετικά με την επίδραση διαφορετικών συνθηκών, στην πιθανότητα επιβίωσης των αυγών και συνεπώς και επανένταξης νέων ατόμων στο φυσικό περιβάλλον. / Gilthead seabream is a species of high commercial interest. It is very important for Greek fish farming. Although, there has been great research on the species, there are still many questions unanswered, especially in the area of reproduction. This study gives information regarding the egg buoyancy of farmed gilthead seabream coming from the Atlantic or the Mediterranean, under natural or late photoperiod, during the whole reproduction period (4,5 months)and under 7 different salinities (32, 33, 34, 35, 36, 37, 38 ppt). Salinity at reproduction was 40 ppt. The diameter of the eggs was also measured (at 32 and 35 ppt). The results have particular ecological interest, as they allow the formation of some hypothesis regarding the influence of different factors in the recruitment of gilthead seabream in nature.
96

Estudo genético de períodos parciais de produção de ovos em codornas de corte / Genetic study of partial periods of meat-type quail egg production

Ribeiro, Jeferson Corrêa 23 July 2010 (has links)
Made available in DSpace on 2015-03-26T13:42:20Z (GMT). No. of bitstreams: 1 texto completo.pdf: 726201 bytes, checksum: 74d4f315d608a52cd33e55e848a74abd (MD5) Previous issue date: 2010-07-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this study was to estimate genetic and phenotypic parameters for egg production and egg mass in meat-type quails and to propose an optimal age for selection of meat-type quails through egg production and egg mass ratio. The data used for this study came from 3.503 female meat-type quails, (UFV1: 1.811 quails; UFV2: 1.692 quails) of the Breeding Program for Poultry, at Federal University of Viçosa. Laying was assessed by the number of eggs produced from the 42th day of life on. For the study on egg production, the traits analyzed were: partial periods of egg production until 77 days (N77), 112 days (N112), 147 days (N147), 182 days (N182) and total production period of 407 days (N407) through the use of a single and bi-trait animal model. For the study on egg mass, the characteristics analyzed were: egg mass in partial periods until 77 days (M77), 112 days (M112), 147 days (M147), 182 days (M182), and egg mass in the total period of 407 days (M407). To analyze the efficiency of selection in each partial period, in relation to the total period, it was used the relative efficiency. For the egg production trait, considering the genetic group UFV1, heritability for N77, N112, N147, N182 and N407 were 0.03, 0.06, 0.07, 0.08, and 0.16, respectively. The estimate of genetic correlation was higher between N112 and N407 (0.64). For other partial periods (N77xN407, and N147xN407 N182xN407), the values of genetic correlation ranged from 0.34 to 0.49. For the genetic group UFV2, the heritabilities for N77, N112, N147, N182 and N407 were, respectively, 0.20, 0.23, 0.25, 0.25, and 0.22. The correlation between each partial period with the total period presented median values ranging from 0.44 to 0.47. The relative efficiency for both genetic groups did not exceed the unity. The highest value found for the genetic group UFV1 was 0.4 during the period N112. For the genetic group UFV2, the highest relative efficiency was 0.49 for the periods N147 and N182. Considering the trait egg mass, the genetic group UFV1 obtained heritability values equal to 0.58 (M77), 0.59 (M112), 0.57 (M147), 0.59 (M182) and 0.24 (M407 ). The values for genetic correlations were medium, ranging from 0.51 (M77xM407) to 0.61 (M112xM407, M147xM407). For the genetic group UFV2, the heritabilities were of low magnitude: 0.05 (M77), 0.03 (M112), 0.04 (M147), 0.05 (M182) and 0.11 (M407). The values for genetic correlation ranged from 0.61 (M112xM407) to 0.93 (M77xM407). The highest relative efficiency value (0.96) was found during the period M112, to the genetic group UFV1, and 0.62 in the period M77 to the genetic group UFV2. Thus, the partial periods for egg production would be important to assist in the selection of meat-type quails, but the selection would be more efficient considering the total production. However, the use of selection through the mass of eggs until 112 days would be particularly interesting for genetic group UFV1, because the efficiency was close to the unity and the generation interval would be greatly reduced. For the group UFV2, even if it has presented low values of relative efficiency, it would only benefit from the reduction in generation interval for selection through the mass of eggs in the partial period until 77 days because it would allow three generations per year. / Objetivou-se nesse trabalho estimar parâmetros genéticos e fenotípicos para produção de ovos e massa de ovos em codornas de corte e propor uma idade ideal para seleção de codornas de corte através da produção de ovos e massa de ovos. Os dados utilizados para esse estudo são provenientes de 3503 codornas de corte, sendo 1811 fêmeas UFV1 e 1692 fêmeas UFV2, pertencentes ao Programa de Melhoramento Genético de Aves da Universidade Federal de Viçosa. A postura foi avaliada por meio do número de ovos a partir do 42º dia de vida. Para o estudo sobre produção de ovos, as características analisadas foram períodos parciais de produção de ovos até 77 dias (N77), até 112 dias (N112), até 147 dias (N147), até 182 dias (N182) e período de produção total até 407 dias (N407), através do modelo animal uni e bicaracterístico. Para o estudo sobre massa de ovos, as características analisadas foram massa de ovos em períodos parciais até 77 dias (M77), até 112 dias (M112), até 147 dias (M147), até 182 dias (M182) e massa de ovos no período total, até 407 dias (M407). Para analisar a eficiência de seleção em cada período parcial em relação ao período total, foi utilizada a eficiência relativa. Para a característica produção de ovos, considerando o grupo genético UFV1, as herdabilidades para N77, N112, N147, N182 e N407 foram respectivamente, 0,03, 0,06, 0,07, 0,08 e 0,16. A estimativa de correlação genética mais alta foi entre N112 e N407 (0,64). Para os outros períodos parciais (N77xN407, N147xN407 e N182xN407), os valores de correlação genética variaram de 0,34 a 0,49. Para o grupo genético UFV2, as estimativas de herdabilidades para N77, N112, N147, N182 e N407 foram respectivamente, 0,20, 0,23, 0,25, 0,25 e 0,22. A correlação genética entre cada período parcial com o período total apresentou valores medianos variando de 0,44 a 0,47. A eficiência relativa para ambos os grupos genéticos não ultrapassaram a unidade. O maior valor encontrado para o grupo genético UFV1 foi de 0,4 no período parcial N112. Para o grupo genético UFV2, o maior valor de eficiência relativa foi de 0,49 para os períodos parciais N147 e N182. Considerando a característica massa de ovos, o grupo genético UFV1 obteve valores de herdabilidade iguais a 0,58 (M77), 0,59 (M112), 0,57 (M147), 0,59 (M182) e 0,24 (M407). Os valores de correlação genética foram medianos, variando de 0,51 (M77xM407) a 0,61 (M112xM407, M147xM407). Para o grupo genético UFV2, as estimativas de herdabilidades foram de baixa magnitude sendo 0,05 (M77), 0,03 (M112), 0,04 (M147), 0,05 (M182) e 0,11 (M407). Os valores de correlação genética variaram de 0,61 (M112xM407) a 0,93 (M77xM407). O maior valor de eficiência relativa encontrado foi de 0,96 no período parcial M112, para o grupo genético UFV1 e 0,62 no período parcial M77, para o grupo genético UFV2. Desta forma, os períodos parciais para produção de ovos seriam importantes para auxiliar no processo de seleção de codornas de corte, mas a seleção seria mais eficiente considerando a produção total. Entretanto, o uso da seleção através da massa de ovos até 112 dias seria particularmente interessante para o grupo genético UFV1, pois a eficiência foi próxima da unidade e o intervalo de geração seria bastante reduzido. Para o grupo genético UFV2, mesmo que tenha apresentado valores de eficiência relativa baixos, se beneficiaria apenas da redução no intervalo de geração para a seleção através da massa de ovos no período parcial até 77 dias, pois possibilitaria três gerações por ano.
97

Circuit and Behavioral Basis of Egg-Laying Site Selection in Drosophila melanogaster

Zhu, Edward January 2015 (has links)
<p>One of the outstanding goals of neuroscience is to understand how neural circuits are assembled to produce context appropriate behavior. In an ever changing environment, it is critical for animals to be able to flexibly respond to different stimuli to optimize their behavioral responses accordingly. Oviposition, or the process of choosing where to lay eggs, is an important behavior for egg-laying animals, yet the neural mechanisms of this behavior are still not completely understood. Here, we use the genetically tractable organism, Drosophila melanogaster, to investigate how the brain decides which substrates are best for egg deposition. We show that flies prefer to lay eggs away from UV light and that induction egg-laying correlates with increased movement away from UV. Both egg-laying and movement aversion of UV are mediated through R7 photoreceptors, but only movement aversion is mediated through Dm8 amacrine neurons. We then identify octopaminergic neurons as being potential modulators of egg-laying output. Collectively, this work reveals new insights into the neural mechanisms that govern Drosophila egg-laying behavior.</p> / Dissertation
98

Impact of breath group control on the speech of normals and individuals with cerebral palsy

Yip, Fiona Pik Ying January 2008 (has links)
Dysarthria is one of the most common signs of speech impairment in the cerebral palsy (CP) population. Facilitating strategies for speech enhancement in this population often include training on speech breathing. Treatment efficacy studies with cross-system measures in this population are needed for improved understanding and management of the interrelationship between respiratory, phonatory, and articulatory systems. The purpose of this study was to investigate the effect of breath group control on the coordination of articulatory and phonatory muscles and the acoustic measures related to speech and voice quality. A simultaneous acoustic, electroglottographic (EGG), and marker-based facial tracking recording system was employed to monitor the speech production behaviors of four adults with CP and 16 neurologically healthy controls. Subjects were instructed to perform three tasks, each containing speech targets with a voiceless plosive (/p/, /t/, or /k/) preceding a vowel (/i/, /a/, /u/, or /ɔ/). Task 1 consisted of a short reading passage embedded with target vowels without cueing from breath group markers. Task 2 included reading a series of monosyllabic and 3-syllable or 5-syllable non-speech words with the speech targets. Task 3 included reading the same short passage from Task 1 with cueing from breath group markers separating the passage into phrases with no more than five syllables per phrase. Measures from the acoustic, EGG and facial tracking recordings of the first and last syllable of all syllable trains produced in the non-speech task and the target vowels in the passage reading task were examined. Acoustic measures included voice onset time (VOT), vowel duration, fundamental frequency (F0), percent jitter (%jitter), percent shimmer (%shimmer), signal-to-noise ratio (SNR), and frequencies of Formants one and two (F1 and F2). EGG measures included speed quotient (SQ) and open quotient (OQ). Facial tracking measures consisted of maximum jaw displacement. Individual and averaged data were submitted to a series of two-way Analysis of Variances (ANOVAs) or two-way Repeated Measures ANOVAs to determine the effects of the relative position of an utterance in the breath group and the place of articulation of the consonants involved. In addition, mean vowel spaces derived from all three tasks were examined. Results revealed significant changes of VOT, F1, F2, SNR and SQ as a function of position. Significant changes of VOT, vowel duration, F2, F0, %jitter, %shimmer, and maximum jaw displacement as a function of place of articulation were also evident. In particular, breath group control was found to result in expansion of vowel space, especially for individuals with CP. These findings suggest that proper phrasing enhances articulatory and phonatory stability, providing empirical evidences in support of its usage in treating individuals with CP.
99

Study of the mechanisms of protein folding

Morgan, Charles J. January 1998 (has links)
No description available.
100

Study of the aggregation behaviour of egg yolk lecithin/bile salt mixtures by increasing the ionic strength

Madenci, Dilek January 2009 (has links)
This thesis describes a study of the aggregational behaviour of egg yolk lecithin (EYL), a natural lecithin, and bile salt mixtures especially with respect to an increase of the ionic strength of the solvent. Mixtures of two amphiphiles with very different spontaneous curvature as EYL lecithin and bile salt form mixed micelles and vesicles in aqueous solution. Their properties have been well-studied under physiological conditions, i.e. 150 mM electrolyte concentration and pH 7- 8, while other conditions are still hardly explored. Upon increasing ionic strength the formed structures and the transitional pathways (micelles, coexistence of micelles and vesicles, and vesicles) change the generated structures completely from those observed under physiological conditions. We quantitatively determined these structures formed in a broad range of electrolyte concentrations with various scattering techniques, x-ray, light and neutron scattering and calorimetry. With calorimetry, phase diagrams in the EYL and bile salt concentration phase plane were determined at various ionic strength ranging from physiological salt concentration to up to 1000 mM. Additionally a new electrochemical approach using functionalised electrodes, i.e. sensitive and selective to bile salt, and thus to control the bile salt concentration in solution (concentrations below the critical micellar concentration (cmc)) was attempted, since bile salt removal or injection drives the micelle-to-vesicle or the vesicle-to-micelle transition, respectively, of the mixed aggregational system of EYL/bile salt. Although this control was not achieved within the framework of this thesis, promising results show directions for future experiments.

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