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16 Uppsatser om Ovulation - Sida 1 av 2

Reproductive physiology of the female cat

The cat is one of our most common pets. Understanding the reproductive physiology of the queen is important, not only for the knowledge of our domestic cats but also for wild undomesticated feline species, many of which have been reported endangered. Understanding the mechanisms behind the estrous cycle, Ovulation and pregnancy is also important for handling the feral cat populations that are a problem in several countries. The purpose of this literature study is to look into the hormonal patterns of the reproductive physiology of the female cat, with focus on Ovulation, pregnancy and pseudo-pregnancy, and from this information determine in which fields more research would be needed. The female cat is seasonally polyestrous in Sweden, meaning that she can have several estrous cycles during the breeding season but goes through a long period of reproductive dormancy during the darker months of the year. The queen is considered an induced ovulator, with copulation triggering the release of luteinizing hormone (LH) from the pituitary gland needed for Ovulation.

Inhibiting the IGF-1 receptor with the cyclolignan Picropodophyllin: an in vitro study of ovulation, implantation and receptivity in a mouse model

Picropodophyllin (PPP) is an analogue of the anti tumour lignan podophyllotoxin with the unique ability to selectively inhibit the receptor of Insulin like growth factor 1(IGF-1). IGF-1 is believed to play an important part in development of the endometrium facing implantation. With PPP treated mice, studies can be made to measure gene expression from tissue of both treated and untreated mice to compare the role of IGF-1 regarding Ovulation, implantation and receptivity. The aim of this study was to analyze gene expression of some steroid hormone receptors and cytokines in ovaries from mice treated with PPP. In this study, seven mice were treated with PPP at different times and tissue was collected.

Brunstvisningsförmåga hos mjölkkor- en beteendenstudie

Oestrus in dairy cattle has changed over the last decades; the intensity of oestrus has declined and the duration decreased. Several studies have shown that not all dairy cows stand to be mounted, and that oestrus expression in many cases may be characterized by other behaviours. The aim of this study was to investigate oestrus behaviour in a herd of todays? high producing dairy cattle. The study was carried out at Jälla naturbruksgymnasium in Uppsala during one week in January 2011.

Genes involved in ovulation rate and litter size in sheep

Fertilitetsegenskaper har ofta låga arvbarheter och selektion baserat på fenotyp är ofta ineffektiv och långsam. För att förbättra fertilitetsegenskaper som Ovulationsmängd och kullstorlek hos får är det effektivast att selektera avelsdjur utefter deras genotyp. Olika mutationer i gener tillhörande transforming growth factor-? (TGF?) superfamiljen har visat sig påverka Ovulationsmängd och kullstorlek hos får. Dessa gener är BMPR-1B, BMP15 och GDF9.

Induktion av persisterande gulkropp hos sto : en framtida metod för att dämpa brunstrelaterade störningar?

This article starts with a review of the literature regarding the normal reproductive physiology of the mare, normal luteolysis, different causes of prolonged luteal phase and theories behind these. The article also presents a study where it was examined if treatment with human choriongonadotropic hormone (hCG) during the luteal phase induces prolonged luteal phase in mares, thus preventing estrus. The study consisted of two parts: one intensive study of eight mares at the former Department of Obstetrics and Gynaecology at SLU, Uppsala, Sweden and one field study of seven mares at a stud farm 70 km north of Uppsala. The mares in the intensive study were divided in two groups: one with four mares that were injected with hCG in luteal phase when they had a follicle of minimum 30 mm and a second group with four mares that were injected with sodium chloride at the same time. These mares were examined with ultrasonography and blood samples.

Kemisk kommunikation hos häst

Feromoner är substanser som används vid kemisk kommunikation mellan individer av samma art. Hos häst har ännu inga feromoner identifierats men studier gjorda i Litauen tyder på att kresoler, ämnen som bildas i tarmen vid nedbrytning av bland annat aminosyror och som utsöndras via urin och avföring, kan ha feromon effekt hos häst.Syftet med detta examensarbete var att undersöka förekomsten av kresoler och andra substanser i urin och brunstsekret från ston i östrus med hänsyn till variation mellan dagar i brunst och mellan provmaterial.Prover samlades in från 8 ston under 10 brunster och vid tre tillfällen från ston i diöstrus. Uppsamling av flyktiga substanser från urin- och sekretproverna gjordes med ?Solid Phase Micro Extraction? (SPME). För separering och identifiering av substanserna användes gaskromatografi och masspektrometri.

Äggstocksaktivitet hos älgar (Alces alces)under älgjaktsperioderna i Jämtland

Älgstammen har stor betydelse för jägares rekreation, turism och som livsmedel. För att älgstammen ska vara en hållbar naturresurs i längden krävs en välfungerande reproduktion. Under hösten 2011 har reproduktionsorgan tillsammans med ytterligare material och data från 90 älghondjur samlats in från Fyringens älgtilldelningsområde i Jämtlands läns. Insamlingen gjordes under två perioder, tre veckor i september (5 - 24/9) samt från 10 oktober till början av november. Uppehållet gjordes under den 2-veckorsperiod, det så kallade ?brunstuppehållet?, (25/9 ? 10/10) då jakt ej är tillåtet.

Registrering och avel för brunstvisningsförmåga hos mjölkkor

Dairy farmers using artificial insemination (AI) are dependent on effective oestrus detection. In Sweden, AI is used for a majority of all dairy cows and oestrus synchronisation with hormones is not allowed. There are reports of declining ability to express oestrus with higher levels of milk production. This makes oestrus detection more difficult. Several aids for oestrus detection have been developed, for instance pedometers and mounting detectors.

Interspecies embryo transfer in South American camelids : a field study

The aim of this study was to investigate the possibility of performing inter-species embryo transfer under actual field conditions in the natural habitat of South American camelids. In this study embryos from llamas were transferred to alpaca recipients. In a parallel study alpaca embryos were transferred to llama recipients. All animals used were free of uterine and ovarian abnormalities detectable by rectal palpation and /or ultrasound examination. Embryos were harvested twice after single Ovulation in 10 mated female llamas and non-surgically transferred to synchronized alpaca recipients.

Avelsarbete med mjölkproducerande getter ? fokus på Norge och Frankrike

The main part of the goats in the world is located in developing countries, whereas active breeding programs are mainly restricted to Northern America and Europe. Goat milk can be processed to several products and goat cheese is the main product. An organized breeding program is carried out in France and Norway but is not present in Sweden. Important selection traits for milk producing goats include milk, protein and fat yield along with protein and fat content. Functional traits have been more important the past years and they have large economic importance for the farmers.

Naturlig familjeplanering : Kvinnor och mäns upplevenser samt sjuksköterskans kunskap och användningsområden

Syftet med studien var att beskriva hur kvinnor och män upplevde naturlig familjeplanering (NFP) samt vilken kunskap sjuksköterskan hade om NFP och när hon kunde använda sig av den i sin profession. Artiklar valdes ut från databaserna Elin, Pub Med och Blackwell synergy. De sökord som användes var NFP, Catholic, Satisfaction, Awareness, Odeblad, Billing, Billings, Nurse, Pregnancy, Birthcontrol, Family, Mucus, Family planning, Natural family planning och Ovulation. Sammanlagt valdes 18 artiklar ut varav 14 användes i resultatet. Två artiklar till resultatet söktes manuellt och beställdes.

Äggstockscysta hos mjölkkor

The presence of cystic ovarian follicles represents an important ovarian dysfunction and is a major cause of reproductive failure in dairy cattle. A cystic ovarian follicle is a persistent follicular-like structure on one or both of the ovaries. It is at least 2,5cm in diameter and it has to persist for at least ten days while a corpus luteum is missing. There are two kinds of cystic ovarian follicles, those who have a progesterone production and those who have not. A clear definition for this condition is lacking, probably because the heterogeneity of the clinical signs and the complexity of the disorder.

Kons fertilitet : kostnader och åtgärder

To get a good economy on the dairy farms the fertility control of heifers and cows is a crucial factor. It is also important to know which key parameters that should be tracked. In this work well established routines for heat detection have to be applied. When the dairy farmers use technical aid in estrus control it is important not to forget that technical aids can not replace the human eye. Approximately 50 % of all opportunities to inseminate are missed because clear signs of estrus have not been displayed and/or recorded. The cattle fertility has been declining over recent years. During the same time the cow?s proceeds have increased, consequently applying a higher pressure on the cow and the manager.

Honlig reproduktionsfysiologi hos lodjur (Lynx lynx)

Knowledge in reproduction in the Swedish lynx (Lynx lynx) is important forseveral reasons. Situated on top of the food chain, lynxes may be at risk of beingexposed to environmental toxins that could have adverse effect on reproduction.The population of lynxes is today managed by restricted hunting which demandsknowledge about both the lynxes numbers and their reproduction. In addition,lynxes may function as indicators of climate change for instance if their season ofheat would be earlier or prolonged due to a warmer climate. Today?s knowledgein reproduction in Swedish lynx is mainly based on information gathered fromradio collared animals.

Glukokortikoiders inverkan på fertiliteten hos ston med kvarstående betäckningsinducerad endometrit

Kvarstående endometrit efter betäckning eller insemination, "perstistant mating-induced endometritis" (PMIE) har länge orsakat problem med fertiliteten hos ston och anses i vissa fall vara den största anledningen till infertilitet. Ett av de tydligaste tecknen på att ett sto drabbats av PMIE är att det finns ?2cm vätska i livmodern 6-24 timmar efter betäckning/insemination. Det inte har funnits några standardiserade behandlingsprotokoll för PMIE men nya studier har visat en markant ökning i dräktighetsfrekvensen när ston som identifierats som predisponerade för PMIE har behandlats med glukokortikoider innan betäckning/insemination. När ston med antingen tidigare oförklarad infertilitet eller tidigare symtom på PMIE behandlats med prednisolon innan insemination har dräktighetsprocenten ökat från 3% till 65% dräktighet samt från 0% till 64,5% dräktighet.

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