During the last decades the Fertility of dairy cows has declined in the same rate as the milk yield has increased. This is a result of the negative genetic correlation between milk yield and Fertility, failure to show estrous signs and metabolic problems in the cow. The purpose of this review was to investigate the function of metabolites and hormones as markers for disturbances in Fertility, health and production in the dairy cow. There are several metabolites that are suggested to indicate the cow?s energy balance.

The aim of this literature review was to suggest suitable index traits to use in the Swedish Sheep Recording Scheme for Fertility and maternal traits. Since Fertility and some of the maternal traits are not normally distributed advanced methodology is needed to calculate genetic parameters. Breeding is a tool to improve the economy of the farm and for the selection of breeders estimated breeding values (EBV) for important traits are of high value. In sheep breeding both lambs born and lambs weaned should be taken into consideration as well as the ewe?s maternal ability, which includes lambing ease, lamb survival, ewe behaviour as mother and the early growth of the lambs.

Variations in Fertility have caused a problematic situation in Sweden among other European countries. According to the Council of Europe we are facing an economic and demographic challenge, when the baby boomers of the 1940?s are retiring. Economists have for a long time studied the connection between economic factors and Fertility, and several studies have found a correlation between business cycles and birth rates. This connection is again of current interest 2008, when a financial bubble bursts at the same time as a baby boom occurs.

Variations in Fertility have caused a problematic situation in Sweden among other European countries. According to the Council of Europe we are facing an economic and demographic challenge, when the baby boomers of the 1940?s are retiring. Economists have for a long time studied the connection between economic factors and Fertility, and several studies have found a correlation between business cycles and birth rates. This connection is again of current interest 2008, when a financial bubble bursts at the same time as a baby boom occurs.

Striga hermonthica, a parasitic weed, has long been believed to be correlated with the declining soil Fertility status. However scientists have recently come to question this statement since some recent studies have shown contradictive results. To investigate whether soil Fertility status and infestation of Striga hermonthica were correlated and the impact of it were caused by farmer management, 120 farmers in Western Kenya, where Striga hermonthica infestation is prone, participated in this study. In three districts with two sub-locations each, farmers answered a structural questionnaire and identified two fields, one with high and one with low soil Fertility. These fields later came to be the basis for this study and soil were therefore also sampled from them.

The Fertility of dairy cows is of great importance in order to maintain high production. The decline in Fertility of dairy cows the latest decades can have several explanations. The large emphasis on high yielding cows and the negative genetic correlation between milk production and Fertility traits could be one of the main factors for impaired Fertility. To find heats and inseminate the cow at the right time is crucial to receive high conception rate. Delaval has, in corporation with FOSS, developed Herd Navigator which is a management program that measure four biological parameters in the milk; progesterone, betahydroxybutyrate, lactate dehydrogenase and urea.

Calcareous fens constitute a specific habitat which is uncommon in Europe and protected by the EU habitat directive due to its importance to several threatened species. Hagebyhöga in Östergötland is a calcareous fen habitat included in the Natura 2000 Networking Programme. Adjacent to the existing fen, a degraded fen area is situated. The area has been used for agriculture for several years but is now going to be restored to its former state by the county administrative board of Östergötland.When working with restoration of degraded fen areas it is important to aquire knowledge about the chemical soil conditions. Plant growth limited by phosphorus and low Fertility are characteristic conditions for calcareous fens, whilst arable land usually is highly fertile and limited by nitrogen.The purpose of this study is to bring forth useful knowledge for restoring the degraded calcareous fen of Hagebyhöga.

The dairy cow?s ability to resume estrus after calving and to conceive is affected by their metabolic status after calving. For high yielding cows there is a high risk that the feed intake will not be sufficient to cope with the increased energy demands after calving, and the cow will end up in a state of negative energy balance. Energy balance can be measured in various ways, for example by body condition score or by plasma concentration of several metabolic hormones and metabolites. After calving, endocrine pathways stimulate tissue mobilization; insulin signaling is blocked, the concentration of insulin-like growth factor-1(IGF-1) and leptin decreases, and the concentration of growth hormone (GH) increases.

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.

The purpose of this literature study was to describe the seasonal reproduction in sheep and the presence of genetic variation in Fertility traits. Methods to induce oestrus are described and the possibilities to change the reproduction season through breeding are discussed. Sheep have a pronounced seasonality in their reproduction. Mating season starts in the fall and the lambs are born during the spring because this is the most beneficial time. The market request for lamb meat has increased and therefore it is desirable with ewes that could get pregnant all year round.

Recording and analyses of superovulation results and Fertility records at the nucleus herd Viken The development of different reproductive technologies aim at increasing the number of progeny per individual parent, and in that improving the possibility of genetic progress. One technique, embryo transfer, have facilitated genetic dissemination and shortened the generation interval also in females. Nötcenter Viken is a company that run embryo collection and embryo transfer in the breeds Swedish Red and Swedish Holstein. It is located outside Falköping. Information is continuously gathered about cows tested at the nucleus herd.

Complex Vertebral Malformation (CVM) is an autosomal recessive inherited defect in the Holstein breed. The defect has lead to structurally malformed calves and losses of pregnancies. To determine the effect of CVM on Fertility in the Swedish Holstein Breed 375 Holstein bulls used in breeding by Svensk Avel and Skånesemin were assigned to this study. 228 bulls matched the criteria of birth year, 1995-1999, > 75 inseminations and a known CVM-status. Of the total 228 bulls 53 of them were CVM-carriers and 175 were non-carriers. The SAS-programme was used to determine the effects of CVM-status, the bull?s father and birth year on Non-return rates (NRR) for 28, 56 and 168 days.

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.

Millions of preselected progeny have been born since the development of The Beltsville Sperm Sexing Technology 1986. The method is based on flow cytometry and sorting is done on the basis of DNA difference of the X- and Y-chromosomes. Preselection of progeny provides an opportunity to obtain genetic gain and increased production as well as increased animal welfare and decreased environmental impact. However, the method is associated with low Fertility, high costs and uncertainty whether the sorting process contributes to DNA damage and thereby results in genetically impaired progeny. Today, sex sorted sperm is only commercially available in the bovine industry, due to the fact that bull sperm is more suitable for selection than sperm from other species.

The Swedish beef cattle population is growing when the dairy cattle become fewer. The Fertility of the beef cows is important for the profitability in beef cattle production. Today there is no genetic evaluation for female Fertility in Swedish beef cows. The purpose of this study was to see if calving interval can be used in the genetic evaluation as a measure of female Fertility in beef cows. For this purpose the variation in calving interval for beef cows of different breeds and ages registred in KAP was studied.