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.

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.

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.

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.

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.

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.

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.

In some herds it has been observed that extremely short teats have become a problem; with a negative influence on the milking performance. The aim of this study was therefore to investigate to what degree the quality of the teats and the milk in cows with short teats is affected as compared with cows with normal teat length and furthermore if the milking performance could be improved by using a liner adapted to short teats. This study was divided in two parts. In the first part, it was examined if there were any differences between short teats and teats with normal length with reference to the milking performance, udder emptying, teat treatment, milk quality, and udder health. 11 pairs of cows were used and in each pair of cows one cow had teats shorter than 40 mm while the other cow had teats longer than 50 mm.

Livestock of pastoralists provide meat, milk, blood, dung and are useful for transportation purposes. In semi-arid and arid areas with very low precipitation the herder must often walk far distances to feed the livestock. This affects the animals? production, especially of milk. Previous studies have investigated how to improve milk production in terms of milking strategies in cattle.

In modern dairy production the milking frequency is increased in some herds due to introducing of automatic milking systems or the farmers decision to milk high producing dairy cows more than two times a day. With more frequent milkings the milk yield increases while the content of fat and protein decreases. However, how the composition of protein is influenced is not fully evaluated. The purpose of this study was therefore to see if a higher milking frequency had any impact on the milk production and especially on the protein composition. This study was conducted as a half udder experiment.

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.

Escherichia (E) coli is one of the most common udder pathogens associated with acute clinical mastitis in Swedish dairy cows. The aim of this study is to review some of the existing literature on E coli mastitis from a Swedish perspective. The bacteria, its most important characteristics, and diagnostics under field conditions is covered, as well as what happens during infection, how E coli affects the cow and which consequences this have. Clinical symptoms associated with E coli mastitis are described and information on when these cases of mastitis usually occurs is given. Risk factors in the cow?s enviroment are described as well as the importance of the cow?s immune defence.