Approximately 20% of the milk within the udder of a cow is stored in the cistern and immediately available for milk removal, while activation of the milk ejection reflex is required for removing the remaining milk stored in the alveolar compartment. The aim of this literature review is to describe, evaluate and consider implications of the three different suckling activities that the calf displays during a suckling bout. In terms of milking, these phases are represented by pre-stimulation, stimulation during milking and post-stimulation. Pre-stimulation is commonly performed in order to induce the milk ejection reflex, whereby the hormone oxytocin is released and the alveoli in the secretory tissue are contracted. Time requirements regarding pre-stimulation must be considered in relation to lactation stage and milking interval.

An automatic milking (AM) system should be combined with some form of controlled cow traffic to minimize the time spend on fetching cows to milking and to increase the milking frequency. By restricting the hours spent on pasture per day you optimise the AM system use during pasture period. A reason for this is becuase cows do not return to the stable for milking during night which cause that the milking unit stands empty those hours. In organic production it is required that the cows should be able to graze a certain amount of daily dry matter (DM) intake on the pasture. In the county of Dalarna where the farm is located the yield of the pasture is about 3000 kg DM per grazing season and hectar.This means that the pasture area should be 14,25 hectare to 57 milking cows.

Today automatic milking systems (AMS) are growing in popularity. In these systems the cows are loose and have to get to the robot and the feed on their own. The cows ranking in this system affect their welfare. In this study data from seven years in an AMS was used and analysed. The aim was to investigate how ranking could affect the behaviour of the cows at milking and at feeding.

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) provide the opportunity for less manual labour and an increased milking frequency. But in order to reach an optimal milking frequency a well-functioning cow traffic is crucial. There are many factors affecting cow traffic but one factor that has not been studied thoroughly yet is the effect of different light intensities during the night, 22.00 h to 05.00 h. Therefore the aim of this study was to determine the effect of different light intensities during the night on number of selection gate passages (GP), milking frequency and milk yield. The study was conducted as a Latin square were three light intensities were applied: LOW (11 ± 3 lux), INT (33 ± 1 lux) and HIGH (74 ± 6 lux), in three different herds.

Milk ejection in dairy cows can be inhibited if oxytocin is not released from the pituitary gland. The problem with inhibition of the milk let down is not new, but has recently regained interest. It is observed during different types of emotional stress, for example when cows are moved to an unfamiliar environment, during oestrus, changing from suckling to Machine milking or when being milked for the first time. The aim of the study was to examine the extent of cows with disturbed milk ejection in Sweden. A survey was sent out to 1000 dairy farmers in order to collect data about herd size, housing systems and routines at calving and milking.

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 purpose with this study was to investigate how the behaviour and physiological parameters differ between high ranked and low ranked cows, and between cows in an automatic milking system verses conventional milking parlour. The study was carried out at the Kungsängen research Centre, Department of animal nutrition an management, Swedish University of Agriculture Sciences, Uppsala. Twelve cows, the six highest and the six lowest in social rank were selected from the automatic milking system for the experiment. Ten cows, the five highest and five lowest in social rank were selected from the conventional system. Blood samples were taken during milking and resting.

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.

Abstract (in English)The work that lead to a CE- marking and the creation of a total drawing foundation on an existing machine carried out on the company Polytec Composites Sweden AB in Ljungby. The company have design an machine that exist in six example that runs in the production. To be able to use the machine the company have to work out a CE-marking. The process that summed up all the document that needs for the machine to make a CE-marking. The documentation includes a total drawing over the machine and a risk analysis performed by a group employers on the company.

Resignations are common in all business sectors and can also be found among forest machine operators in the forest business. As the industry today faces a lack of forest machine operators it is justified to determine why machine operators choose to quit their jobs. The aim of this study was to a) find out the number of machine operators that have resigned b) identify and analyse the cause for these resignations c) identify the reasons why the machine operators started to work in the forest and d) give suggestions on different measures that will limit resignations amongst forest machine operators. A questionnaire was sent to machine operators who have quit working as employees, contractors or as employees for contractors with Holmen Skog during 2003-2007. 32 machine operators responded to the questionnaire. Interviews were made with 10 machine operators who had answered the questionnaire to gather more qualitative data. The results of the study indicate that fewer forest machine operators change profession than employees in other occupations in Sweden.

Habituation to an automatic milking system (AMS) for cows in their first lactation differs from habituation to other milking systems. In AMS the cows are supposed to visit the milking station (MS) voluntarily. The milking takes place individually during the whole day, except when the milking system is cleaned. Milking is carried out without any human survey. The aim of the study was to describe the cow?s introduction in AMS in their first lactation.

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.

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.

The aim of this study was to investigate the relationship between sleep, photoperiod, milk yield and hormones connected to milk formation. Variations of prolactin (PRL) and Insulin-Like growth factor-1 (IGF-1) in plasma were measured during two different light programs. The light programs consisted of either 24 hours of light (L24:D0) or four hours of light and 20 hours of darkness (L4:D20). Five cows of the Swedish Red breed were used in a cross-over experiment and each light program consisted of five days. Milk yield was measured at every milking and milk samples were analyzed with regard to fat, lactose and protein.