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.

Inbreeding has become a problem in some horse breeds. Studies show that it may lead to inbreeding depression which affects e.g. reproduction traits. In the wild there are mechanisms that make horses avoid mating with close relatives. When selection is done by humans this mechanism is removed and intensive breeding for a few traits, for example good racing results, can become a problem.

Smallholder farmers in Uganda suffer from declining productivity. With a rapidly increasing population, marginal land is taken into production and the current land management leads to loss in soil Fertility and escalation in soil erosion. There are studies indicating that the use of agroforestry increases soil organic carbon (SOC) compared to systems without trees. Soils which are high in carbon have many advantages, for example better water holding capacity, which can reduce stress on crops during drought. The aim of this study was to determine the effect agroforestry has on SOC concentration in small-holder farming systems in Uganda. The intended system to study was farms practicing agroforestry methods or not in intercropped plantain (cooking banana) fields.

In Sweden there are about 4 million hectares of bare peat (mire). This land has great potential to be transformed into productive forest land, provided drainage is carried out and, in some cases, even fertilization with ashes. Drainage of mires is necessary because the high groundwater table prevents trees from growing due to reduced oxygen availability. Some of the key nutrients that trees need to grow appear in too small quantities in mires, especially potassium (K) and phosphorus (P). Ash from the combustion of biomass contains these elements and is therefore suitable as a fertilizer.

This project investigated how elevation and vegetation type influences variation in plant litter phenolic content and protein precipitation capacity among and within common plant species for two different vegetation types, heath and meadow, in a subarctic ecosystem in the Abisko region of northern Sweden. As nutrient availability generally decreases with increasing elevation as a result of decreasing temperature, I hypothesised that phenolic content would increase with elevation and be higher on the heath than the meadow. To test this, the total phenolic content and protein precipitation capacity was estimated in leaf litter from 13 species in both heath and meadow vegetation across an elevational gradient ranging from 500 to 1000 meters above sea level (m.a.s.l.) in the study region. The results showed that elevation and vegetation type both had a strong impact on both variables. Total phenolic concentrations decreased with elevation for the meadow, and were greater for the heath than the meadow.

Aim: The purpose of this study was to describe, analyze and compare university students? desire to have children, when they wanted to have their first and last child and their knowledge about fecundity in relation to the background factors: age, gender and educational level. This study will also investigate differences regarding university students? desire to have children along with when they wanted to have their first and last child and their knowledge of declining fecundity at increasing age. Method: A descriptive, comparative, cross-sectional study with quantitative method was used in the study.

Cassava (Manihot esculenta Crantz) is a root crop that plays an important role in many households in Africa. It is sometimes called ?Africa´s food insurance?. The advantages with the crop are that cassava is drought-resistant and it can grow in a semi-dry land. It is a perennial crop and does not require much labor.

The aim of this paper was to explain protein degradation in silage and protein quality and biogenic amines in silage and their effects on the health of the dairy cows. After harvest-ing, the plant proteases degrade the proteins in the plant. The protein degrades to different fractions with different digestibilites in the rumen. Fraction A contains non- protein nitro-gen which is peptides, free amino acids and amines. True protein is in the fraction B and is further divided into three subfractions depending on their solubility.

The Swedish boreal forests are limited by nitrogen (N) availability. While biological N2 fixation by cyanobacteria hosted by pleurocarpous feather mosses are important sources of N input to natural boreal forest ecosystems, little is known about the patterns of N2 fixation in silvicultural systems. This study investigates the biological N2 fixation rates of two boreal feather moss species (Pleurozium schreberi and Hylocomium splendens) along a chronosequence from clear-cut to mature forest, as well as the vegetation characteristics along the chronosequence. Measurements and samples were collected from 32 forest sites that were classified into four age classes (clear-cut, pre-commercially thinned, thinned and mature forest). The sites were located near the city of Arvidsjaur in northern Sweden.

Tidigare forskning har ägnat sig åt att försöka förklara det sjunkande barnafödandet i Europa. En av dessa forskare, Richard Easterlin, har format en hypotes där han menar att förklaringen ligger i ett samband mellan kohortstorlek och fruktsamhet. En annan forskare, Jean-Claude Chesnais, har på senare tid testat denna hypotes på sambandet mellan relativ kohortstorlek och nettoreproduktionstal på 18 länder i världen under åren 1930 till 1980 och kommit fram till att detta samband inte existerar under denna tidsperiod i dessa länder. Vi har, i vår undersökning, gjort en fortsättning på Chesnais studie genom att testa sambandet mellan relativ kohortstorlek och summerad fruktsamhet i åtta Europeiska länder mellan 1980 och 2005. Resultatet blev det samma som Chesnais, det vill säga att det inte finns något synligt samband mellan dessa två faktorer.

In today?s genetic evaluation of Swedish beef cattle, mainly traits that are directly related to productivity are measured. However, other traits, such as temperament and mature cow weight affect the economy of the farmer, as well as the welfare of the animals. This thesis evaluates possible ways of measuring new traits, with focus on temperament and mature weight of suckler cows. The goal is to examine the possible benefits of including these traits in the Swedish breeding scheme.

Selenium (Se) is an essential trace element that is involved in several physiological functions in mammals. Mostly, Se is bound to proteins, many of them with enzymatic functions. A group of seleno-depending enzymes, glutathione peroxidases (GSH-Px?s), are important as antioxidants and protects against free radicals. The activity of GSH-Px is strongly regulated by Se storage in the liver.

Rapid population growth and the fact that phosphorous is a limited resource implies that the question regarding an efficient use of phosphorus is of great importance, and consequently,that the phosphorous use efficiency should be as high as possible. The view on phosphorous use efficiency, and how this is calculated, has varied over time. This has had great implications on what type of research that has been conducted, which have resulted in an inconsistency between the academic?s view on the subject and recommendations received by farmers. The purpose of this paper is to calculate the phosphorus use efficiency in the Swedish long term Fertility experiments.

Fertiliteten hos högavkastande mjölkkor i världen har en negativ trend. Eftersom brunststyrkan avtagit i takt med att mjölkproduktionen ökat, och lantbrukarna har allt mindre tid avsatt för observation av sina djur, finns en växande marknad för automatiska brunstpassningssystem. I denna studie utvärderas ett sådant system; Heatime®. Arbetet är tvådelat, och består av en retrospektiv studie av den eventuella förändring i besättningarnas fertilitetsresultat som uppkommit efter installation av systemet och en enkätstudie som utvärderade hur nöjda 65 lantbrukare var efter inköp. Efter att ha granskat och jämfört fertilitetsdata (antal kor, inkalvningsålder, kalvningsintervall (KI), kalvning till första insemination (KFI), kalvning till sista insemination (KSI), antal inseminationer/serie, 56 dagar non-return, andel dräktiga av nypåbörjade och dräktighetsprocent per insemination) från de databaser som finns i Sverige (kokontroll och seminrapportering) från två år före installation med två år efter konstaterades att dessa värden inte skiljde sig signifikant åt. Detta beror antagligen på att fertiliteten hos mjölkkor är så pass multifaktoriell att det finns fler faktorer än bara brunstpassning som påverkar resultaten. Resultaten av enkätundersökningen visade att majoriteten (94 %) av de som köpt systemet var så pass nöjda att de skulle köpa det igen, och 96 % av dem tyckte sig se en förbättring av fertilitetsresultaten efter installation. Vidare uppgav 76 % att de ansåg sig spara väsentligt med tid varje vecka efter installation av Heatime®. Om tid sparas varje arbetsdag utan negativ påverkan på fruktsamheten får detta ses som en vinst och skulle kunna motivera en installation av systemet.

Claw health has been recorded by claw trimmers at trimming in Sweden since 1996, but data was then captured at each AI association. From 2003 data was captured by central scanning and entered directly to the national cow data base at the Swedish Dairy Association (SDA). This reporting was introduced because SDA wanted to be able to use these records to improve dairy cow claw health by breeding. It is desirable with cows that have healthy claws, because poor claw health can contribute to impaired production and Fertility. The claw health report begins with some information about herd, claw trimmer, date et cetera and continues with the part where the claw health is recorded. Here the ID of each cow is filled in and on the same row the conditions for dermatitis, heel horn erosion, sole haemorrhage and sole ulcer are recorded as no lesion (blank), slight lesion (/) or severe lesion (X).