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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

Effect of high and low dosage of fresh and frozen semen on accessory sperm number, fertility and embryo quality in artificially inseminated cattle /

Nadir, Sher, January 1992 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 54-59). Also available via the Internet.
2

Population genetics and sperm physiology associated with genome resource banking in the eld's deer

Harnal, Veera Kumari. January 1999 (has links)
Genome resource banking (collection, storage and use of germ plasm) has emerged as a potentially powerful tool to assist in managing and conserving endangered species. The development of genome resource banks is multi-faceted. This thesis focused on aspects of population genetics and the phenomenon of sperm capacitation, a fundamental biological process crucial to the use of germ plasm for assisted breeding (i.e., artificial insemination, in vitro fertilization). Computerized simulation modeling, using two endangered species models, the Eld's deer (Cervus eldi thamin ) and Pr-zewalski's horse (Equus przewalskii) clearly demonstrated the value of certain sperm storage and use strategies for maintaining genetic diversity in captive populations. Laboratory studies with Eld's deer sperm examining a host of conventional strategies (developed in livestock) demonstrated clear challenges in provoking capacitation and the acrosome reaction in the Eld's deer. This finding reaffirmed the importance of species-specific studies in wildlife research.
3

Population genetics and sperm physiology associated with genome resource banking in the eld's deer

Harnal, Veera Kumari. January 1999 (has links)
No description available.
4

Effect of high and low dosage of fresh and frozen semen on accessory sperm number, fertility and embryo quality in artificially inseminated cattle

Nadir, Sher 22 October 2009 (has links)
This study was designed to : 1) Determine the effects of fresh vs frozen semen at a high inseminate dosage (lOOxl06sperm) contrasted to their effects at a conventional dosage (20xl06 sperm) on accessory sperm per ovum and 2) Evaluate the relationship between accessory sperm number per embry%vum and fertilization status/embryo quality if accessory sperm number were affected by treatment. In this study semen from four bulls routinely giving a minimum of 700/0 morphologically normal and 600/0 motile sperm cells were used. Ejaculates of these bulls were split and prepared for use as fresh and frozen semen at either 100xl06 or 20xI06 cells per dose in.5 mL French straws. Half of the total semen filled straws were frozen in liquid nitrogen at -196°C and half were stored at 5°C for 4 days after collection and used as unfrozen. Cows in standing heat were inseminated with fresh or frozen semen at either high (IOOxl06 sperm) or conventional dose (20xl06 sperm). Ova/embryos were recovered non surgically on day 6 after breeding. Accessory sperm were counted in the recovered embryos/ova after partial digestion with Pronase followed by compression of the embryo/ovum with a cover slip. From 129 inseminations to normally cycling cows, 98 embryos/ova were recovered. To reduce male effects, embryos/ova used were randomly balanced across treatments, by ejaculate within bull for evaluation of frozen vs fresh semen (n = SO) and by bull for evaluation of high vs low dosage treatments (n = 76). No difference (P > 0.05) in accessory sperm was observed for fresh vs frozen semen at either the high or low dosage. The mean accessory sperm values for fresh high dose (n=21), frozen high dose (n=21), fresh low dose (n= 19), and frozen low dose (n= 19) were 26.S1±30.23 (SD), 36.05±44.74 (SD), 29.37± 55.97 (SD) and 30.l6± 70.18 (SD) respectively. When data for embryos/ova resulting from fresh and frozen semen were pooled within dosage, a significant difference was observed between the median accessory sperm values for high and low doses of semen (P < .05). Mean ± SD and median values for accessory sperm were: 37.8± 38.3 and 27.5; 28.9± 62.8 and 3.0, for the high and low dose, respectively. Increasing accessory sperm number by the higher dosage improved the fertilization status/embryo quality (P < .05). Percentage unfertilized ova, degenerate embryos and embryos classified poor to fair and good to excellent were: 3, 5, 24, 68; and 21, 16, 18, 45, for the high and low dose, respectively. Overall, embryos/ova classified good to excellent, poor to fair, degenerate and unfertilized had median accessory sperm values of 18, 9.5, 5.5 and 0, respectively. However, the lack of accessory sperm in unfertilized ova was significantly different from excellent-good quality embryos (P < .05). / Master of Science
5

The viability and fertility of bovine spermatozoa encapsulated in microcapsules and microgels

Munkittrick, Thomas Wright January 1989 (has links)
Four experiments were conducted to evaluate the viability and fertility of bovine spermatozoa encapsulated in microcapsules and microgels. In Experiment I, one of two morphologically distinct sperm types i.e. marker or unmarked bull spermatozoa (100 x 10⁶ sperm/bull) were encapsulated in protamine sulfate microcapsules and simultaneously inseminated with the reciprocal sperm type unencapsulated. Insemination of both sperm types unencapsulated served as a control. Accessory sperm embedded in the zona pellucida were counted and morphologically classified 6 to 7 d post insemination. From microencapsulated inseminates, accessory sperm populations did not increase over the unencapsulated controls, but contributed 25.7% of the accessory sperm population. ln Experiment 2, an in vitro study was performed to evaluate the maintenance of viability for bovine spermatozoa encapsulated in PIPES, HEPES, or saline microgels. Neat semen was pooled from five bulls (50 x 10° sperm/bull), encapsulated in alginate microgels, and incubated at 37 C for 8 h. The unencapsulated control displayed greater maintenance of viability for percent intact acrosomes and motility when compared to all treatments. By 8 h incubation, PlPES and HEPES were not significantly different, but demonstrated greater maintenance of viability when compared to saline microgel treatments. In Experiment 3, PIPES microgels were heterospermically inseminated with equal numbers (20 x l0⁶ sperm/bull) of frozen-thawed marker bull and normal bull spermatozoa as explained in Experiment 1. Microencapsulated treatments contributed significantly lower numbers of accessory sperm when compared to unencapsulated controls. In Experiment 4, one of the two morphologically distinct sperm types (20 x l0⁶ frozen-thawed sperm/bull) were encapsulated in protamine sulfate microcapsules and the reciprocal sperm type was encapsulated in PIPES microgels. A total of 21 accessory sperm were recovered from 30 embryos which demonstrates the ability of microencapsulated spermatozoa to fertilize an oocyte. / Master of Science
6

Anonimozegratuitos = a transformação da pessoa em informação e da informação em pessoa / Anonimozegratuitos : person is information and information is person

Novaes, Thiago O. S., 1979- 03 August 2012 (has links)
Orientador: Mauro William Barbosa de Almeida / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-20T00:51:52Z (GMT). No. of bitstreams: 1 Novaes_ThiagoO.S._M.pdf: 859789 bytes, checksum: 2b41a9c3740f2c6d670ce587dc67ead2 (MD5) Previous issue date: 2012 / Resumo: A dissertação apresenta um novo conceito, anonimozegratuitos, que pretende realizar uma dupla operação: a transformação da pessoa em informação e da informação em pessoa. Inserindose nos correntes debates da antropologia da ciência e da técnica, o texto descreve o funcionamento de três objetos técnicos na Internet - a WikiPedia, o WikiLeaks e o BitTorrent - relacionando-os às noções de autoria, propriedade intelectual, troca e gratuidade. Trata ainda das técnicas de reprodução assistida em relação à doação anônima e gratuita de sêmen, que provoca uma ruptura sobre o auto-reconhecimento da unidade da espécie humana, situando a emergência da eugenia liberal junto ao modelo tecnocientífico que viabiliza a procriação autônoma de mulheres solteiras e a seleção de material genético para melhoramento da saúde humana / Abstract: The dissertation presents a new concept, anonimozegratuitos, which promotes a double operation: the transformation of person in information and information in person. Attentive to the current discussions of the anthropology of science and technology, the text describes the operation of three technical objects on the Internet - the WikiPedia, WikiLeaks and BitTorrent - relating them to the notions of authorship, intellectual property and free exchange. It also discusses the techniques of assisted reproduction in relation to free and anonymous donation of sperm, which causes a disruption of the self-recognition of the unity of the human species, placing the emergence of liberal eugenics with the technoscientific model that enables the autonomous reproduction of single women and selection of genetic material for improving human health / Mestrado / Antropologia Social / Mestre em Antropologia Social
7

Vida esterilizada: reflexões biopolíticas sobre as estratégias de comercialização de sêmen no Banco California Cryobank

Mazzilli, Paola 13 December 2017 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-12-20T11:52:27Z No. of bitstreams: 1 Paola Mazzilli.pdf: 26906244 bytes, checksum: f7c79628fb3e6201bcb5c3daae7a8f58 (MD5) / Made available in DSpace on 2017-12-20T11:52:27Z (GMT). No. of bitstreams: 1 Paola Mazzilli.pdf: 26906244 bytes, checksum: f7c79628fb3e6201bcb5c3daae7a8f58 (MD5) Previous issue date: 2017-12-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The present work aimed at investigating and problematizing the global human sperm bank market, at the beginning of the 21st century. In view of the significant increase in sperm imports in Brazil (2,625% between 2011 and 2016) and the interest in premium donor catalogs, we carried out an exploratory study that could unravel its offer. Our purpose was to understand how the advertising strategies of this market would promote the expectation of a child ‘customization’, from the possibility of selecting an ‘ideal’ biological father. In addition, we deem it necessary to reflect on the new meanings attributed to motherhood, fatherhood and birth itself, considering progresses in the fields of biotechnology and genetics. To do so, we collected current data on the fertility market, paying special attention to the national and international commercialization of sperm. We also addressed the ‘parallel market’, where ‘independent’ donors provide their services in a paid or free basis. Finally, we conducted a case study of California Cryobank, one of the most important banks in the world. In order to understand its business dynamics, we decided to discuss it in two stages: the first one was devoted to its services offer and the second one to the catalog of its donors, which was statistically and discursively analyzed in its entirety (533 ads). We then identified what would be the main attributes that, a priori, would characterize these ‘premium’ donors. From the theoretical point of view, we preferred a transversal approach with special emphasis on contemporary authors dealing with biopower and biotechnology. We hope that the research developed may contribute to new debates, in that it articulates, in an unprecedented and representative way, empirical data and academic reflections / O presente trabalho buscou investigar e problematizar o mercado internacional de sêmen humano, no início do século XXI. Diante do expressivo aumento de importações deste produto no Brasil (2.625% entre 2011 e 2016) e o interesse por catálogos de doadores “premium”, julgamos oportuno um estudo exploratório que pudesse destrinchar sua oferta. Nosso propósito foi compreender de que modo as estratégias publicitárias desse mercado promoveriam a expectativa de “customização” de um filho, a partir da possibilidade de seleção de um pai biológico “ideal”. Além disso, julgamos necessário refletir sobre os novos significados atribuídos à maternidade, à paternidade e ao próprio nascimento, frente aos avanços nos campos da biotecnologia e genética. Para tanto, coletamos dados atuais sobre o mercado da fertilidade, atentando-nos, especialmente, à comercialização nacional e internacional de sêmen. Abordamos, ainda, o mercado paralelo, onde doadores “autônomos” prestam seus serviços de forma paga ou gratuita. Finalmente, realizamos um estudo de caso do California Cryobank, um dos bancos mais importantes do mundo. Visando a entender sua dinâmica de negócio, optamos por discuti-lo em duas etapas: a primeira dedicou- se à oferta de seus serviços e, a segunda, ao catálogo de seus doadores, que foi analisado na íntegra (533 anúncios) estatística e discursivamente. Identificamos, então, quais seriam os principais atributos que, a priori, caracterizariam esses doadores “premium”. Do ponto de vista teórico, preferimos uma abordagem transversal com especial ênfase nos autores contemporâneos que versam sobre biopoder e biotecnologia. Esperamos que a pesquisa desenvolvida possa contribuir para novos debates, na medida em que articula, de maneira inédita e representativa, dados empíricos e reflexões acadêmicas

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