Mastitis, an inflammation of the udder mainly caused by a bacterial infection, induces an increase in the somatic cell count (SCC) in milk and is consequently one of several factors affecting SCC in milk. In this literature review it is investigated whether SCC; on udder quarter, cow composite or bulk tank milk level, can be used as a quality marker with focus on milk composition in terms of the content of fat, lactose, total protein, casein and whey protein. According to this literature review the relation between SCC and milk composition is not reliable either on udder quarter, cow composite or bulk tank milk level. SCC was related to lactose, casein and whey protein on Udder quarter level; lactose and whey protein on cow composite level and lactose on bulk tank milk level.

Developments in milk production are heading towards fewer but larger herds where the milking process is often fully automated. Automatic milking systems were launched in the 1990?s and in the year 2010 the Automatic Milking Rotary (AMR) was introduced. As a rule there are no supervision personnel present during the milking event in systems with automatic milking. This means that there is a risk that cows can be incompletely milked in one or more udder quarters, for example if the robots fail in attaching the milking cups or if the cow kicks off the milking unit.

Subclinical mastitis (SCM) is a well-known problem in the dairy sector, where it causes severe economic losses mainly due to reduced milk production. This is a problem not only in the western world but also in developing countries. Surveys from different developing countries have shown a SCM prevalence of 52.4 ? 88.6 % at cow level and 26.7 ? 63.2 % at quarter-level. To combat mastitis is important to optimize the milk production of the cow.

Syftet med försöket har varit att utröna hur den naturliga variationen ser ut från dag till dag imjölk från separata juverdelar och hur sammansättningen i mjölken skiljer sig inom kor medolika juverhälsa. I den här studien användes 10 kor från Sveriges Lantbruks Universitet sommjölkades kontinuerligt, 2 gånger per dag i 21 dagar på juverfjärdedelsnivå. Mjölken vägdesvid varje mjölkning och analyserades sedan på antal somatiska celler (SCC), laktos, fett,protein, kasein och vassle protein. Resultaten visar att det är signifikanta skillnader imjölksammansättning mellan juverfjärdedel inom ko. För variation är mjölkmängd denparameter som varierar mest och varierar väldigt mycket mellan juverfjärdedelar.

Dairy farming in Uganda provides a source of food, employment and income. Previous studies have revealed high frequencies of bovine mastitis, a costly disease for the dairy farmer. The aims of this study were to investigate the bacteriological panorama in milk from udder quarters with clinical (CM) and subclinical mastitis (SCM) and to determine the antimicrobial susceptibility in staphylococcal isolates. Further, we intended to establish the prevalence of subclinical mastitis and to investigate some environmental factors and animal properties that might influence the frequency of mastitis. For CM, farmers made contact with the members of this study when recognizing an animal with CM.

The milk production has developed rapidly the last years. The milk production per cow is increasing and the production units are larger with an increasing number of animals and a decreasing number of workers. Many milk producers invest in automatic milking systems (AM) to meet this change. In these systems the cows can voluntary decide milking frequency and usually the milking frequency are higher than two times per day. But how does the milking frequency effect the composition of the milk? The aim of the present study was to study the effect of milking frequency on the milk composition and the milk fat quality.

Today the milk production per cow is increasing but the milk delivered by the Swedish farmer contains less amounts of fat and protein than earlier. The contents have decreased since 1993. In average the milk contain 4,2 percent fat and 3,4 percent protein. Earlier the fat content in milk was important. Nowadays the dairy?s attention has turned to the milk?s valuable proteins, principally the caseins, which have a considerable nutritional value and are important for several dairy products like cheese and yoghurt.

Mastit är en sjukdom som leder till stora problem i svenska mjölkkobesättningar. De flesta mastiter är subkliniska inflammationer som ofta inte upptäcks på grund av avsaknaden av synliga sjukdomssymtom, men där SCC är förhöjt och mjölkkvaliteten försämrad precis som vid klinisk mastit. Detta leder till att mjölk med förändrad sammansättning och kvalitet levereras till mejerierna som därmed har sämre förutsättningar att framställa mejeriprodukter av hög kvalitet. Även lantbrukaren drabbas ekonomiskt, dels på grund av att ett förhöjt celltal inte ger maximalt betalt för mjölken och dels på grund av en minskad mjölkmängd då all mjölk från kor med konstaterad subklinisk mastit ofta kasseras. Vid mjölkning i automatiska mjölkningssystem finns möjlighet att separera mjölken på fjärdedelsnivå redan vid mjölkning, detta sker dock inte idag.

Mastitis in dairy cows is an emerging and challenging disease in the tropics, including India. Nation-wide reports suggest that the incidence of clinical mastitis varies from 3.94% to 23.25%, and for subclinical mastitis from 15.78% to 81.60%. In Assam, a northeastern province of India, dairy is an essential part of the mixed farming system that exists in the state, but the milk yield is far below domestic standards. In 2009-2010, International Livestock Research Institute (ILRI) and local associates started to develop a training program for local farmers in Assam, in order to enhance the informal bovine dairy sector in and around Guwahati, India. The project continued until mid-2013.

Today, there are more than 12 000-14 000 farms worldwide using an automatic milking system (AMS). Studies have shown that transition to AMS affects the udder health of cows adversely, recognized primarily as elevated somatic cell counts. There are several reasons for this, for example the greater variation in milking frequency seen in AMS. On one hand, short milking intervals may lead to bad teat condition of the cows due to the stress the milking procedure exposes the teats to. Too long milking intervals, on the other hand, seem to predispose for milk leakage, which is, in turn, a risk factor for the development of mastitis.

Mastitis, inflammation in the udder tissue, caused by S. aureus is a big problem in dairy cattle production. It causes suffering for the cow and curing or replacing the infected cow is costly for the farmer. It is known that beef cattle also suffer from mastitis caused by S. aureus.

SAMMANFATTNINGMastit är den vanligaste och mest kostsamma sjukdomen hos mjölkkor. Enligt statistik från Svensk Mjölk har cirka 65 % av alla kor i Sverige mastit någon gång under en laktation. Subklinisk (utan märkbara symtom) mastit utgör det största problemet. De är svåra att upptäcka då även mjölken ser normal ut, vilket resulterar i att den hamnar i tanken och levereras till mejeriet. Mjölk från kor med mastit har ett ökat celltal samt försämrad kvalitet och sammansättning vilket i slutändan medför sämre betalt för lantbrukaren.

Automatic milking systems (AMS) have been in commercial use since 1992 and have since 1998 increased a lot. The objective of this study has been to examine the development of udder health on farms converting to AMS. The study also included a comparison of how udder health developed depending on how farms handled cows with mastitis. This was because farms choose to either milk cows with mastitis in a separate barn or in the milking robot. Other studies on udder health on commercial farms have shown that somatic cell count increases both among individual cows and in the bulk milk when converting to an AMS. No differences between before and after converting to AMS in the proportion of cows treated for mastitis can be found in the literature.

The objective of this work was to evaluate and compare three field methods for detection of mastitis, California Mastits Test (CMT), DeLaval cell counter DCC (DCC) and FMA2001 Farm Milk Analyzer (FMA2001). Furthermore, to investigate at what cell count level clinical symptoms of mastitis are seen, and finally to check if the clinical findings and cell counts could be related to bacteriological findings. DCC and FMA2001 are new analytic instruments to be used on dairy farms for detection of mastitis. CMT has been a widely used cow-side-test of milk quality in mastitis control efforts, but it cannot be used for estimating cell counts in scientific studies or investigations. Two hundred and eight quarter milk samples from 52 cows were analysed with DCC and CMT, and 168 of these samples with FMA2001. Microbiological examination was done on 38 milk samples with CMT scores of 4 and 5.

A comparative thesis to study precious metals impact on a portfolio, during a long period of time, from the fourth quarter of 1986 to the third quarter of 2012. Five different portfolios are compared; three of the portfolios containing one of the following precious metals, gold, silver and platinum, the fourth portfolio contain all precious metals and shares, and the fifth portfolio containing only shares which is represented of OMXS30. This is done to determine the portfolio that generates the most return in relation to the least risk with the help of historical prices. Sharpe ratio is used to measure the profitability of precious metals by measuring the yield relative to the total risk. The study also measures precious metals correlation with shares..