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3809 Uppsatser om Gender-selected semen - Sida 1 av 254
Kvalitetsbedömning av selekterad och oselekterad hingstsperma med hjälp av flödescytometri och fluorometri, före och efter seminsäsongen :
Most Swedish Warmbloods are bred by artificial insemination (AI). Quality control of the semen consists of the subjective evaluation of motility. There is a need for a more accurate and objective method of rating the semen. In this study we compared fluorometry with flowcytometry as a method for evaluating sperm viability. Semen was collected from three stallions, stationed at Markebäcks Gård, Askersund, three times during week 15 and week 34, 2008.
Effekt av spädningsvätska på spermiemembranintegritet analyserad med NucleoCounter SP-100 :
This study is a part of a larger project where the aim has been to evaluate different methods to assure the quality in stallion semen, due to the fact that some stallions in horse breeding have poor semen quality. The increased use of transport semen requires new methods to ensure good semen quality.
In this part of the project the viability and concentration in fresh and cooled semen was examined with NucleoCounter SP-100. A comparison between two different commercially available semen extenders, Kenney?s and INRA 96, was made.
Förekomst av leukocyter i råsperma hos semingaltar :
Detection of leukocytes in semen from boars is part of the routine control of semen quality. Leukocytes in semen can cause damage to spermatozoa that leads to impaired fertilization. In the artificial insemination (AI) industry there are standard routines for the quality control of the boars and of the neat semen before use. Since 2001, Quality Genetics has not done the leukocyte examination on semen samples from boars which are used for the production of pigs for slaughter.
The purpose of this study was to investigate the occurrence of leukocytes in semen from AI-boars. The questions addressed were whether there are boars that have leukocytes in their semen and how frequently it occurs and, moreover, if there are differences between breeds, or even between individuals whose semen was checked before use in AI-dose production compared to those which were not.
The study included a total of 135 AI-boars, of which 67 were Hampshire, 35 Yorkshire and 33 Landrace, all belonging to Quality Genetics AI-station in Hållsta.
Användning av könssorterad sperma i nötkreatursaveln :
Almost for as long as there has been breeding on bovine species, there has been a wish to have a higher proportion of offspring of either one or the other gender. In dairy cattle, heifers are more valuable, while in beef stock bulls are preferred. Semen is sorted based on the difference in DNA content between the X- and Y-chromosome in the genome of the sperm. X-chromosomes contain on average between 3,70 to 4,22% more genetic material than the Y-chromosome. Commercially it is the method of flow cytometry that is being used, which is always under improvement.
Utvärdering av viabilitet hos selekterad hingstsperma med hjälp av fluorometri :
There is considerable variation between stallions in semen quality and fertility due to the fact that selection of stallions for breeding is not based on fertility or semen quality but on performance. The increasing use of cooled semen for artificial insemination has resulted in decreasing pregnancy rates. Therefore the equine breeding industry needs new methods for evaluation and development of sperm quality and fertility. This study is a part of such a project and is performed by SLU in cooperation with Flyinge AB. Ten stallions at the Flyinge National Stud were used in the study and three ejaculates were collected from each stallion.
Kvinnors och mäns motiv och ambivalens till att donera ägg och spermier i Sverige
Involuntary childlessness is a big problem around the world. One way to solve the problem is to receive oocytes or semen from a donor. In Sweden, semen donation has been regulated by law since 1985 and oocyte donation since 2003. The aim of this study was to investigate what motivations women and men in Sweden have to donate gametes, if they feel any ambivalence to donate, and to compare if there is any difference in motivation and ambivalence between women and men. Motivation was measured with eight statements based on previous results and clinical experience.
Bedömning av spermiemotilitet i färsk, kyld samt selekterad hingstsperma med Qualisperm :
This EEF-project is a part of a larger project at SLU, Division of Reproduction,
Dept of Clinical Science, with the intention of developing and evaluating new
methods for the assessment of stallion semen quality. Over the last 10 years there
has been an increase in the use of artificial insemination with cooled semen in
Swedish horse breeding. At the same time, foaling rates have decreased. This has
lead to a need for new and better methods of assessing the quality of stallion
semen. This EEF-project was based on an objective method to calculate motility,
with QualispermTM, in fresh and cooled stallion semen, and after selection.
Today sperm motility evaluation is mainly done subjectively by visual assessment
with a light microscope, and the correlation between these motility results and
fertility have varied.
Typografins gränsland : Om genusnormer i förändring
The earlier studies of how gender is visually constructed in lifestyle magazines have mainly been done on photographs. But, photographs are only one part of the entire magazine Therefor3, we saw the importance in examining one of the other big parts, typography.We have been studying if gender can be constructed in lifestyle magazines through the shape and color of typography and the color context. It is important to point out that we have not been studying the written word but only the shape and color of the typography.The study has been conducted through a qualitative content analysis with a comparative process of the selected magazines. The analysis began with a semiotic analysis of selected parts of the magazines. The result was then analyzed with a feminist theoretical approach.The result of the study shows that gender can be constructed through typography in a number of different ways.
När kan Tanzanias fattigdom elimineras? : En analys av bistånd, tillväxt och fattigdom
The aim of my thesis was to examine if educators need to be critical of what they read to the children from a gender perspective. I examined how picture books depict gender and if the books enhances or breaks perception of gender roles. I also examined educator?s perception of gender and if they think picture books can affect children?s perceptions of gender, but also what educators think about gender equality through picture books. The study is based on analysis of five picture books and interview with five educators.The results of analyzes showed that picture books are stereotyped and enhances perceptions of gender roles.
"Skippar prinsessböcker med happy ending" : En kvalitativ studie av genus i fem bilderböcker och fem förskolepedagogers uppfattningar om genus i bilderböcker
The aim of my thesis was to examine if educators need to be critical of what they read to the children from a gender perspective. I examined how picture books depict gender and if the books enhances or breaks perception of gender roles. I also examined educator?s perception of gender and if they think picture books can affect children?s perceptions of gender, but also what educators think about gender equality through picture books. The study is based on analysis of five picture books and interview with five educators.The results of analyzes showed that picture books are stereotyped and enhances perceptions of gender roles.
Kromatinstabilitet som grund för kvalitetsbedömning av hingstsperma :
This study is part of a project to evaluate and develop metods to control the semen quality in stallions. The study was carried out in cooperation between SLU and Flyinge AB. The objective of the study was to analyse
-if there are individual differences in sperm chromatin integrety between different stallions
-if there is a correlation between subjectively evaluated sperm motility and sperm chromatin integrity
-if sperm chromatin integrity is changed after selection of the semen with a centrifugation method through the silica-spheres, gradient or a single-layer, i.e to use the chromatin integrity analysis as a method to evaluate the selection method.
The use of chilled transported semen has increased a lot during the last 10 years, especially among the Swedish warmblood breed. Because the foaling percentage has decreased with the increased use of chilled transported semen, there is a need to develop methods to control the sperm quality. Evaluation of the chromatin integrity could be one way to evaluate the quality of the semen.
Chromatin is the DNA in the nucleus of the sperm.
Framställningen av könsroller i barnböcker : En kvalitativ textanalysstudie av fem hästböcker
The purpose of this paper is to find out which characteristics the female and male characters have in five selected horse books in children's literature. I have analyzed five horse books by Professor Maria Nikolajeva?s gender roles schedule. I have chosen to do a qualitative text analysis and the questions I chose to ask for the books are: Which characteristics does the girls and the boys have in the selected horse books according to Nikolajeva?s gender chart? What is the relationship between the main characters and the horse/horses according to the theories of Backman? What does the typical horse book look like today? What I come to conclusion in my paper is that all the horse books I analyzed have female main characters, and the girls in these books about horses take a lot of space and demonstrate themselves strong.
Utvärdering av en ny selektionsmetod för hingstsperma : med avseende på membranintegriteten och membranstabiliteten
Today, equine breeding is based on performance and conformation, resulting in a vast variation in fertility among different horses, with noticeable economic losses as a consequence. The horse breeding industry is therefore in need of methods that diagnose the spermatozoa concerning their quality and provide the best sperm for AI. The commonly used selection methods for sperm today are: centrifugation, where extender is added, the sample is centrifuged and then resuspended; swim-up self-migration; adherence separation; and density gradient centrifugation. However, none of these methods are in used routinely in practice before inseminating mares with fresh or cooled semen.
The aim of this study was to evaluate a new selection method, Single Layer Centrifugation (SLC), and its effect on sperm viability. The viability was analyzed with regard to membrane integrity and membrane stability of ejaculated spermatozoa.
Effekter av spädningsvätska på motilitet och fertilitet hos hingstsperma : en jämförelse av subjektiv motilitetsbedömning och QualispermTM
At SLU, Divison of Reproduction, Dept of Clinical Science, there is an ongoing project on the development and evaluation of new methods for the assessment of stallion semen quality. This EEF-study, which is a part of that larger project, has focused on the effects on motility and fertility of stallion semen of two different extenders and selection. Both an objective method and a subjective method for analysis have been used and compared in the study.
The increase in the use of artificial insemination with cooled semen in Swedish horse breeding over the last decade is thought to play a part in declining foaling rates (Kareskoski et al, 2006, Kuisma et al, 2006). This calls for better evaluation methods of semen quality since cooling and transportation put higher demands on semen quality in order to maintain fertility (Aurich, 2005).
"Genus är inskränkt!" : En komparativt inriktad studie av genuspedagogik på förskolor i New York och Stockholm
The purpose of this thesis is to examine how teachers work and reflects on gender education in preschools. We also want to take part of how teacher?s thoughts are reflected in the physical indoor environment and how the environment is designed by reviewing the rooms furnishing and the selected materials. We will do this by visiting a number of preschools located in Stockholm and New York. We have chosen three questions to get the answers on our purpose.How teachers reflect around gender pedagogy are, and how the thoughts are expressed in the practical work.How the teachers communicate with their co-workers about gender pedagogy.How the teachers own thoughts and reflections on gender pedagogy have been expressed in the physical indoor environment where the children stay during the day. We have used interviews and observations as a method to gather the information that we needed to answer our questions of the thesis.