The probiotic Bacteria Lactobacillus reuteri DSM17938 was evaluated as a starter culture in cheese production, with the intention to produce a new interesting product within the functional food market. Growth and acidification rate in milk subjected to different heat treatments, as well as supplementation with growth promoting factors or support cultures was measured during controlled fermentations. The results showed that the weak proteolytic activity of L. reuteri could be compensated for by supplementation with 1% casamino acids or 5% MRS broth. Furthermore, a decrease in growth and acidification rate could be seen when using yoghurt culture or Lactobacillus delbrueckii as adjunct cultures.

Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; Bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.

Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; Bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.

Composting is a process in which organic matter is mineralized by microorganisms. In January 2005 landfilling of organic waste was prohibited in Sweden. With this prohibition composting has become an important alternative to handle the produced organic wastes. One problem with continuous small-scale composting is the production of organic acids that will inhibit a further composting process. The aim of these theses was to study what effects temperature and dry matter content had on the production of organics acids, and what effect the organic acids had on the mineralisation of the substrate as well as the stability during storage of the product.

Since the first wolf was taken as a companion animal a lot have happened with the biology of these animals. Is it possible that changes in the gut microbiota of the domestic dog are involved in the increasing numbers of animals with gastrointestinal disorders? Probiotics have been proven to promote the immune system of dogs by increasing concentrations of neutrophils and monocytes, decreasing the fragility of erythrocytes and increasing the serum IgG concentrations. Probiotics have also been shown to improve the fecal consistency, fecal dry matter and defecation frequency of dogs. The aim of this study was to find out if the Bacterial counts in the gut of dogs differed from the gut of wolves, with the focus on lactobacilli.

Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; Bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.

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.

The resting area is the most important place in the barn for the dairy cow, sometimes called the heart of the free stall system. Inadequate design of the lying area, and lack of or poor quality of bedding materials may reduce the hygiene of the stall. Poor management regarding the cleanliness of the resting area may lead to poor animal hygiene and increased Bacterial growth. This in turn will lead to increased risk for environmental mastitis as well as impairing milk quality through contamination with spores. In this literature study the most commonly used bedding materials; straw, sawdust, wood shavings, clean sand, recycled sand, peat and recycled manure solids, are compared to one another with regards to their ability to resist Bacterial growth. Effects of adding hydrated lime to bedding materials have also been studied. Most Bacteria need humidity and prefer a quite high water activity to be able to grow.

Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; Bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.

Lyckeby Starch AB is a farmer-owned company that produces products based on potato starch. In order to increase their production efficiency and their international competitiveness the company is investigating the possibilities of keeping their factories open longer. To achieve this, potato has to be stored for a longer period of time than what is practiced today. Starch potato is usually stored in large piles covered by straw and plastic, either in the field or on the farmyard. The objective was to examine in what way starch yield (starch content*tuber weight) in three different potato varieties was affected by storage in two different types of storage piles. The potato was stored for three months in total and starch content and tuber weight were controlled throughout the period. Stored tubers were also visually examined and prescense of mechanical damage as well as wet rots and dry rots was recorded. Bacteria and fungi were isolated and identified. In general, varietal differences were greater than differences between the storage piles.

Abstract Cavities used to be a very common problem but over time humans have learned to take care of their teeth. However, there are still many who have problems. This problem is due to microorganisms and in particular the various streptococci and lactobacilli producing acids which loosens up the enamel on teeth. These Bacteria can be found at various places in the mouth and saliva. Besides being a discomfort it can be a major problems and the damaged tooth needs to be removed or make a dental filling. The aim of the study was to see how intake of probiotic tablets containing Lactobacillus reuteri PTA ATCC 5289 and Lactobacillus reuteri DSM 17938 affects the levels of oral Streptococcus mutans and lactobacilli over a three-week period.

Objective: To determine the frequency of antimicrobial resistance in Bacteria from healthy Swedish dogs and whether they are carriers of methicillinresistant Staphylococcus aureus (MRSA). Material: Samples from skin from the perineal region and from faeces collected in the anus with cottonswab (Copan) from 299 healthy Swedish dogs. Samples were collected at dog exhibitions. Method: Specimens were submitted for Bacterial culture where Bacteria (Escherichia coli, enterococci and staphylococci) were isolated and identified by current methods. Antimicrobial susceptibility testing was performed with a microdilution method where MIC-values were determined. Staphylococci with high degree of resistance were tested for presence of mecA-gene by PCR.

The main purpose of this study was to determine the impact of bedding material on the faecal microflora of horses. Another objective was to investigate the hygienic and physical qualities of the bedding materials used and how these may change in the course of the trial period. The bedding materials used were sphagnum peat and wood shavings. Six horses had each material as bedding for a three week period in a change?over experiment.

To date, the genus Helicobacter consist of 26 different species and even more species are yet to be characterized. Helicobacter has been detected in connection with diseases in the liver and pancreas in humans and animals. Helicobacter spp. are gram negative, curved, S-shaped or spiral shaped Bacteria. They are microaerophilic and have flagella that make them motile. Helicobacter, present in the gastric mucosa neutralize the gastric acid through production of urease that hydrolyses urea to ammonia and bicarbonate.

Peat litter is a soft material with high absorbency. About hundred years ago many farmers in Sweden used peat litter to their dairy cows. After the World War II the use of peat litter decreased and the farmers used more straw. Nowadays (year 2007), when it is harder to find straw and sawdust to buy, peat litter is advancing again. The purpose with this study is to investigate peat as a litter to dairy cows.