This paper shortly describes the coronavirus family, bovine corona viruses (BCV) properties and two diseases that BCV causes, winter dysentery and calf diarrhoea. The purpose of the study was to compare different diagnostic methods to detect BCV. Different methods are discussed, PCR, ELISA, immunofluorescense and virus isolation. Investigations were made in three different herds with winter dysentery; one dairy cattle farm with about 100 cows of different ages, one testing station for bulls with about 150 bulls and another small dairy cattle farm with 26 cows and 20 replacement Heifers and calves. Faeces and nasal swabs were analysed with PCR and ELISA. The result shows that PCR seems to be a reliable method for detecting BCV but that the ELISA test can not be used as a reliable diagnostic method to analyse samples from animals with winter dysentery..

Since feeding fodder crops to dairy cows is a heavy and time-consuming but often disregarded line of work, this study wishes to view the different possibilities that are currently available to decrease the time to feed and apply this knowledge on an existing farm. For this purpose, four farms have been studied due to what feeding systems that are currently used and how long time the feeding required. The occurring systems are either mobile, i.e. a feed mixer operated by a tractor witch feeds the cattle via a drivable fodder table, or a stationery mixer, i.e. an electrically powered mixer which fills an automatic feeder.

Maize for silage has been used as fodder in different parts of the world for a long time and has recently become more common also in Sweden. Our cold climate has been a problem as maize is very sensitive to low temperatures and frost. With new varieties and better techniques for cultivation it is now possible to grow maize in the southern and middle parts of Sweden. As for the north of Sweden the length of the cultivation season is a limiting factor as there are too few days with temperatures of over +10 ºC. Maize is well suited for silage making but oxygen-free conditions are required.

The purpose of this literature study was to investigate the possibilities to improve longevity and stayability of beef cattle with breeding. The breeding goal for beef breeds is to produce animals with high capacity for growth and good feed efficiency. Longevity and sustainability are two important features to include in the breeding goal. If longevity is increased each cow can produce more calves and the number of female calves used for recruitment can be reduced and only the best Heifers need to be selected for breeding. The benefits of longer life is that it lowers the costs of recruitment animals, it increases the number of young animals that become available for slaughter, and it increases the proportion of high producing animals in the herds.

The purpose of this study was to find out if motion movements, e.g. number of lying bouts and lying time with a registered activity monitoring sensor can detect an impending calving and thereby be used as a measure and an indicator for an upcoming calving. For this, automatically step sensors were used and were attached to one of the cows? hind leg. The sensor registered the individual step and movement activity of the cow.

The objective of this thesis was to get more knowledge about how to design a dairy farm reducing the working hours and the work tasks whit high work load. I will try to reduce the working hours and the tasks whit high work load on my own farm witch I am about inherit. Today, the old stanchion barn has room for about 60 cows and 74 young cattle and need two men to run it every day. The total acre is 188 hectare, 100 hectare forest, 65 hectare farmlands and 23 hectare natural pasture. I have studied two solutions. In the first solution, I will use my old barn for young cattle and build a new barn for the cows.

Difficult calvings and stillborn calves are costly for the producer and lowering these frequencies can decrease the costs for the dairy operation. Each calving in the herd is registered by the farmer and stored in a central database. The information is used to monitor the level of calving-difficulties and stillborn calves in the herd and nationally. Monitoring of these registrations is important to detect possible changes. Breeding-value prediction for calving traits is based on the calving information in the database.

To reconstruct a building is a long-term investment for farmers and it is important that people with different qualifications are involved at an early stage for making the system adapted to the animals as well the animal keeper. Therefore, ethologists who can contribute with their expertise are needed to design the system and get it to function well for the animals.A Swedish farmer who planned to rebuild her stall for tied dairy cattle to a loose-housing system for recruitment Heifers for milk production asked me as an ethologist to find a system which can be fit to her existing tie-stall barn for 30 dairy cows, considering the animal needs in terms of movement, social interactions and play behaviors, and to theoretically compare the system with other systems with respect to the behaviors mentioned.The theoretical comparison between different systems was made through a scientific literature review.In agreement with the animal keeper I set out to fit a system with feeding cubicles, a system with cubicles and a system with deep straw bedding to the barn. After measurements were taken and preliminary drawings were outlined it was found that only the feeding cubicle system was possible to fit to the barn.The space provided will limit the animals to perform some playing behaviors. To decrease aggressive interactions between animals even thought a limiting area it is possible to provide partitions between resources animals compete around to prevent that more than one animal can get success to the resource at a particular place at one time. To increase the animal movement in the system the water trays were moved to the outer wall instead of kept in contact with the stalls.Although this report provides guidelines for rebuilding, other competences regarding building construction and a pre-test of the suggested building solution according to Swedish legislation are needed before the rebuilding can start.The results are directed mainly to the owner of the barn, but the literature review can be used by other cattle farmers and might bring increased understanding of the possible effects of different building solution on the animals..

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.

During natural conditions cattle live in large herds, which are divided into subgroups of 10-15 animals. Humans have held cattle for over 9000 years. Today we mostly have cows for milk and meat production during more or less intensive forms. Most of the Swedish cattle have the opportunity to graze during the summer time. This partly arises from the Swedish Animal Protection law which stipulates that cattle must have the option to be outside and graze, also partly because it makes it easier for the farmer.

Metabolic diseases in dairy cows are considered to increase the risk for claw lesions, most of all laminitis, sole haemorrhages and sole ulcers, but also to increase the risk for environmental claw lesions. The aim of this study was to compare claw health in 27 Swedish dairy farms, 18 with high incidence of metabolic diseases and 9 with low incidence. Data on claw health status was retrieved from recordings at routine claw trimmings and analysed on herd level regarding the prevalence of: any lesion, interdigital dermatitis, heel-horn erosion, sole haemorrhages, sole ulcer, lameness, abnormal claw shape, and other diseases (abscess in the white line, limb disorders, double sole, laminitic groove, white line disease, interdigital phlegmon, interdigital hyperplasia, toe abscess and verucose dermatitis). Mean prevalence of any lesion for herds with low incidence of metabolic diseases was 48 % and in herds with high incidence 41 %, and there was no statistical difference between the two groups. Mean prevalence for interdigital dermatitis was 2,0 % and 6.4 % in the low and high incidence groups, respectively (p.

Feed costs constitute a large part of the expenses of dairy farmers. Pasture is a high quality feed with a low cost. However, feeding with concentrates has been shown to enhance milk yield (Leaver, 1985; Bargo et al., 2003; Stockdale, 2004). The purpose with this study was to investigate how milk yield and milk composition were affected as the concentrate proportion in the diet decreased. Pasture behaviour was examined to see if the different concentrate levels affected the time cows spent grazing and ruminating.

Sweden signed, in 1992, the Convention on Biological Diversity (CBD) and has thus assumed responsibility for the indigenous biodiversity. That also means that Sweden has a conservation responsibility for the Swedish Friesian (SLB) (SJV, 2007a). In a survey conducted by the Board of Agriculture (SJV) in 1996, it appeared that there were around 780 cows and Heifers of the SLB breed (SJV, 1997). SJV did in 2006 a plan for the development of livestock genet-ic resources and the number of cows of SLB was estimated at approximately 200. This meant that the SLB was in need of being conserved and SJV assumed it would be categorized as threatened.The primary objective of conservation of a breed is to reduce the loss of the original genetic variation (Lacy et al., 1995).

Sweden signed, in 1992, the Convention on Biological Diversity (CBD) and has thus assumed responsibility for the indigenous biodiversity. That also means that Sweden has a conservation responsibility for the Swedish Friesian (SLB) (SJV, 2007a). In a survey conducted by the Board of Agriculture (SJV) in 1996, it appeared that there were around 780 cows and Heifers of the SLB breed (SJV, 1997). SJV did in 2006 a plan for the development of livestock genet-ic resources and the number of cows of SLB was estimated at approximately 200. This meant that the SLB was in need of being conserved and SJV assumed it would be categorized as threatened.The primary objective of conservation of a breed is to reduce the loss of the original genetic variation (Lacy et al., 1995).

In Kenya the Maasai pastoralists have based their livelihoods on dairy production and the production goal is to maintain a sufficient milk supply throughout the year. The pastoral dairy production has two vital characteristics; breeding and milking. Traditionally, breeding is the men?s responsibility, while milking is the duty of women. Depending on this partition of chores between men and women, they also have different management routines, ambitions and strategies regarding the milk production.