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.

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.

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.

The dry period is usually 6-8 weeks and in this period the basis of the performance in the following lactation is settled. In an average herd about 15% of the cows are dry (Marcussen & Krog Laursen, 2008). In many herd the dry cows are set aside, that means setting aside 15% of your herd, at the time when they are preparing for their next lactation. The recommendation for number of groups differs depending on country traditions or reasons for grouping. If you look at recommendation for feeding, some companies selling feeding equipment advocates one group throughout the dry period, but the number differs from one to three.

The dry period is usually 6-8 weeks and in this period the basis of the performance in the following lactation is settled. In an average herd about 15% of the cows are dry (Marcussen & Krog Laursen, 2008). In many herd the dry cows are set aside, that means setting aside 15% of your herd, at the time when they are preparing for their next lactation. The recommendation for number of groups differs depending on country traditions or reasons for grouping. If you look at recommendation for feeding, some companies selling feeding equipment advocates one group throughout the dry period, but the number differs from one to three.

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.

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.

The number of weaned piglets per sow and year is a good measurement of sow productivity since it is affected by the number of piglets born alive, the pre weaning mortality (i.e. mortality of live born piglets between birth and weaning) and the number of litters per sow and year. This measure is also closely connected to the number of piglets produced per year, which partly determines the profitability of the piglet producer. During this study, eleven successful piglet-producing herds were visited. Eight of the producers were Swedish and three of the producers were Danish.

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.

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.

The ability of dairy cows to survive and the economic importance of this have been in-creasing in dairy cattle breeding lately. Increased longevity contribute to an increased pro-portion of cows that produce milk in more productive lactations and reduces the replace-ment costs together with a good health and fertility. Unfortunately it is often argued that longevity has been decreasing due to a strong selection for production traits in dairy cattle.The aims of this study were to find correlations between different longevity evaluations and between different estimates on longevity and other traits in the Nordic Total Merit (NTM) breeding value. The aim was also to compare different traits for cows of two differ-ent longevity groups.The data were Predicted Breeding Values (PBV) from Nordic HOL and SR bulls and records from Holstein (HOL) and Swedish Red (SR) cows estimated by the Swedish Dairy Association.The three Swedish longevity indexes were very highly correlated (>0.89) and the corre-lations between the Swedish official longevity index and the five Nordic Cattle Genetic Evaluation (NAV) longevity indexes varied between 0.73-0.83.In the sire evaluation part, the traits most negatively correlated with longevity for HOL were dairyness, protein and fat index. In SR, milk, protein, and fat index only had slightly positive correlations with longevity.

Milk yield levels in dairy cows are influenced by many factors such as nutrition, breed, health status, management and environment. This study was conducted among small scale farmers in Zambia, where the climate can be dry for up to six months per year and cause a lack of green pasture for livestock and on-farm produced feed. The purpose of this study was to identify management factors that can influence milk yield at small scale dairy farms in Zambia, and present advice that could improve productivity, without the need of expensive investments. The study included semi-structured questionnaires presented to the farmers (n=29) including questions about cattle management and milk production. Testing of somatic cell count (SCC) with DCC (DeLaval Cell Counter) from herd milk samples (n=56) and observation of housing and animal body condition on-farm was also made.

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.