Nötcenter Viken is a Swedish nucleus herd for dairy cattle. The goal for the farm is to select suitable mothers for the next top generation of bulls. Today the selection for udder health is based on a pedigree index and phenotype data. The pedigree index is based on the cow?s father and grandfathers breeding values.

With increased milkproduction in our dairy cattle, comes a risk for a reduced fertility. Studies performed on animals and humans have shown that it is possible to manipulate the oestrous cycle through exposure to pheromones. This means that pheromones could potentionally be used to make reproduction more efficient. To evaluate the bioactivity of the substances in question, there is need for a bioassay. In insects, pheromones can induce a changed cardiac activity.

Higher demands of competitiveness and efficiency have led to increasing sizes of farms, with more land, more capital and more comprehensive logistics. The aim is to gain benefits of scale economies that reduce the production cost per unit. However, a greater extent of the business exposes the farm of increased risk where small deviations rapidly can erase the benefits. A modern dairy farm thus put high demands on the farmer?s ability to coordinate, plan and manage the forage production through the whole process until storage to obtain silage of the desired quality and quantity at the right price. The objective of this study was to design a simple model, i.e.

Mastitis is an important disease in dairy cattle. It is very costly for the farmers and affects a large number of animals. Few studies have been made investigating the outcome of treatment for acute clinical mastitis under Swedish conditions, and it can be problematic to use the results in foreign studies since both the microbial flora as well as treatments may be different from the situation in Sweden. In this project we have investigated data on clinical mastitis and antibiotic treatment in the dairy herd at Jällaskolan, Uppsala based on recordings during the last ten years. The material includes both Swedish Red (SRB) and Swedish Holstein (SLB) breeds, which have been kept at the farm under similar conditions.

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.

Concentration of protein in bovine milk is one of the most significant milk quality parameters, to a large extent determining the price for milk to the producer. Mastitis is a common disease among dairy cows, negatively affecting not only milk yield but also milk protein composition. Milk from mastitic cows tends to have lower cheese yield, negatively affected processability properties and sensory quality, due to changed protein quality and composition. Poorer milk protein quality would have an economically negative impact on dairy industry. Only few studies have investigated the short term effects of mastitis on milk protein composition.

Earlier studies of musculoskeletal problems with milkers working in milking parlour operators have shown that it is a physically demanding occupation. The extremities that are most exposed are neck, shoulders, hands and wrists. Those systems that have been studied in present cases are fishbone and some tandem barns. There have been changes in the working environment during the past ten years. The mechanisation has been developed for the better with automatically removers of the milking units and vertically adjustable floors in almost every daily milking barn. In other hand the milk production are more industrialised and more related to stress today.

Approximately 20% of the milk within the udder of a cow is stored in the cistern and immediately available for milk removal, while activation of the milk ejection reflex is required for removing the remaining milk stored in the alveolar compartment. The aim of this literature review is to describe, evaluate and consider implications of the three different suckling activities that the calf displays during a suckling bout. In terms of milking, these phases are represented by pre-stimulation, stimulation during milking and post-stimulation. Pre-stimulation is commonly performed in order to induce the milk ejection reflex, whereby the hormone oxytocin is released and the alveoli in the secretory tissue are contracted. Time requirements regarding pre-stimulation must be considered in relation to lactation stage and milking interval.

Migration and giving birth are crucial decisions for animals during their life cycle, which may have lasting consequences on their population demography and fitness. Migration can entail a variety of possible effects for an individual, such as access to high quality food and reduced risk for predation. The moose (Alces alces) in northern Sweden is partially migratory and moose females are known to give birth to one or two calves. The synchrony between time of calving and timing of migration has not been compared before, especially in terms of energy maximizing and time minimizing perspectives, which may provide vital cues for fitness benefits of migration. I investigated effect of timing of birth and individual life history on distance, timing, stopovers and duration of 190 individually marked female moose that have been tracked for multiple years in ten different areas in northern Sweden.

The Bovine respiratory syncytial virus (BRSV) causes bronchiolitis and interstitial pneumonia, predominantly in calves, and is a major cause of bovine respiratory disease worldwide. In humans, BRSV is paralleled by the closely related Human respiratory syncytial virus (HRSV), an important cause of respiratory disease, most severe in infants.The clinical signs and pathology during RSV infection is caused, not only by the direct effects of viral replication, but also by the response of the host immune system. The immunopathology of RSV has long obfuscated our understanding of the disease, and development of effective treatment and vaccines will be very difficult until greater knowledge is gained.One of the components of the immune system that has come into focus in RSV research the last few years, is the Toll-like receptor 4 (TLR4). The TLR4 receptor is well known as the receptor that binds lipopolysaccaride (LPS), and initiates the host response to bacterial infection. Recently, it has been shown that the fusion protein of RSV also interacts with, and up-regulates the expression of, the TLR4 receptor.

Ravelsmarks gård have now reached the stage when there are few options for the future. The options are either a construction of completely new farm buildings or a winding up of the milk production. Present on the farm today there is 65 dairy cows plus recruitment. 44 cows stand in long-stalls and 20 cows stand in short-stalls. The objective of this study was to examine the profitability of a completely new cowshed. In order to get costs for investments different milking systems and equipment for feedstuff have been compared. The systems in the investment budget have been chosen on recommendations from advisers, salesmen and on the basis on what is suitable for the farm. One system where a so-called mix feeder wagon is used for the roughage seemed to be best suited for Ravelsmark. The different prices obtained for the manure well show that there are possibilities to decrease the investment costs.

The aim of the study was to find repetitive behavioral patterns pre calving that could be used as indications of calving in beef cattle. In the study sixteen Standing- and lying down sensors were attached to the leg of sixteen beef cows. Ten of the sixteen beef cows gave birth to calves during the trial period. From these ten cows, data from six cows were used to assess the sensors fitness for use as calving indicators. The analytical part of the experiment was divided into two parts, calculation of divergence of mean lying time within different time intervals, and the number of lying bouts.The first part consisted of optimization of an equation used to highlight divergence in mean lying time within eight different time intervals (3, 6, 9, 12, 15, 18, 21 and 24 hours).

The Bovine respiratory syncytial virus (BRSV) causes bronchiolitis and interstitial pneumonia, predominantly in calves, and is a major cause of bovine respiratory disease worldwide. In humans, BRSV is paralleled by the closely related Human respiratory syncytial virus (HRSV), an important cause of respiratory disease, most severe in infants.The clinical signs and pathology during RSV infection is caused, not only by the direct effects of viral replication, but also by the response of the host immune system. The immunopathology of RSV has long obfuscated our understanding of the disease, and development of effective treatment and vaccines will be very difficult until greater knowledge is gained.One of the components of the immune system that has come into focus in RSV research the last few years, is the Toll-like receptor 4 (TLR4). The TLR4 receptor is well known as the receptor that binds lipopolysaccaride (LPS), and initiates the host response to bacterial infection. Recently, it has been shown that the fusion protein of RSV also interacts with, and up-regulates the expression of, the TLR4 receptor.

Automatic milking systems (AMS) provide the opportunity for less manual labour and an increased milking frequency. But in order to reach an optimal milking frequency a well-functioning cow traffic is crucial. There are many factors affecting cow traffic but one factor that has not been studied thoroughly yet is the effect of different light intensities during the night, 22.00 h to 05.00 h. Therefore the aim of this study was to determine the effect of different light intensities during the night on number of selection gate passages (GP), milking frequency and milk yield. The study was conducted as a Latin square were three light intensities were applied: LOW (11 ± 3 lux), INT (33 ± 1 lux) and HIGH (74 ± 6 lux), in three different herds.

Den vanligast förekommande sjukdomen hos unga kalvar med infektiös orsak i Sverige är diarré. Enterit kan leda till uttorkning, acidos, rubbningar i elektrolytbalansen och i värsta fall dödsfall. Snabbt insatt behandling är avgörande. Till kalvar med fungerande digestionssystem rekommenderas i första hand behandling med oral vätsketerapi. Endast lite forskning har utförts om hur kalvar helst dricker sitt vatten.