The aim of this project was to quantify the total sleep time in modern dairy cows during24-hour periods and to investigate whether the total amount of sleep as well as timespent in different sleep stages varies between the dry period, early- and peak lactation.The distribution of sleep time between night and day was also examined. Furthermore,correlations between sleep and lying time, fluctuations in body temperature and heartbeat were included in the aim. Eight dairy cows of the Swedish Red breed were used inthis study, which was carried out between June and September 2010. In order toquantify sleep non-invasive electrophysiological recordings were performed.Simultaneously with collecting sleep data, body position and body temperature werealso recorded. No heart rate data was obtained due to difficulties of maintainingelectrodes for heart beat measurements attached to the skin.

Cross-suckling, i.e. when an offspring nurses a female other than their own mother, occurs in pig production systems where sows are group housed during lactation. As production systems where several sows and their litters are housed together during lactation are getting more common, the need of knowledge regarding cross-suckling increases. The overall aims with this thesis was to investigate how sow behaviour and productivity are associated with the occurrence of cross-suckling, and to investigate consistency in sow nursing behaviour related to cross-suckling. The study included information about the first 4 parities of 40 LxY sows kept in outdoor and indoor production environments. Sows were single housed the first 2 weeks after farrowing and group housed (4 or 5 sows per group) from 2 weeks after farrowing until weaning, 7 weeks after farrowing.

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.

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.

Claw health has been recorded by claw trimmers at trimming in Sweden since 1996, but data was then captured at each AI association. From 2003 data was captured by central scanning and entered directly to the national cow data base at the Swedish Dairy Association (SDA). This reporting was introduced because SDA wanted to be able to use these records to improve dairy cow claw health by breeding. It is desirable with cows that have healthy claws, because poor claw health can contribute to impaired production and fertility. The claw health report begins with some information about herd, claw trimmer, date et cetera and continues with the part where the claw health is recorded. Here the ID of each cow is filled in and on the same row the conditions for dermatitis, heel horn erosion, sole haemorrhage and sole ulcer are recorded as no lesion (blank), slight lesion (/) or severe lesion (X).

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.

Milkability or ease of milking, has higher importance today for Swedish dairy cattle producers after the introduction of milking parlours and automatic milking systems. Milkability is the cow?s ability to quickly milk out and be completely milked. There are several measures of milkability available. Today the farmer measures the traits subjectively in relation to the conformation scoring of the cow 30-270 days after her first calving.

The heterosis effect and breed group effect of crossbreds between Swedish Holstein (SH) and Swedish Red (SRB) was estimated in this study. Observations on cows born between 1990 and 2012 were used to estimate the heterosis effect and breed group effect for several traits included in the Nordic breeding goals: production, fertility, udder health, calving performance, survival and other diseases. Breeding within the Holstein dairy breed has earlier been focused on increased milk production and conformation. This, combined with an intensive use of individual animals, has resulted in a radical increase of milk yield in the Holstein dairy cow population all over the world. However, this breeding strategy has resulted in increased inbreeding and several functional traits have impaired.

Six cows were subjected to an intravenous glucose tolerance test (GTT) to evaluate the amount of glucose that is needed to stimulate the release of insulin from pancreas. Four of the cows were in early lactation and two were non-lactating and not pregnant. Series of blood-samples were collected to analyze the concentration of insulin and glucose in the blood. The cows were given lower levels of glucose than have been used in earlier glucose tolerance tests. The levels of glucose given were 7,5 mg/kg BW, 15 mg/kg BW, 30 mg/kg BW and 50 mg/kg BW.

After parturition the energy demand for milk production is greater then the energy provided from the diet. The cow mobilises therefore body tissues to compensate for the energy loss. Live weight and body condition scores decreases as a consequence of the mobilisation. The aim of this study was to analyse the relationship between body condition score, live weight and subcutaneous fat depth measured by ultrasound and the changes during the lactation. Possible differences between Swedish Holstein (SLB) and Swedish Red and White Cattle (SRB) were also investigated.

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.

Live-weight at different ages for Swedish Holsteins (SLB) and for the Swedish Red and White Breed (SRB), and the correlation to heart girth and height at withers. The aim of this investigation was to study the live-weight changes and mature weight for the Swedish Red and White Breed (SRB) and for Swedish Holsteins (SLB), and to estimate the correlations between body weight and body measurements such as heart girth and height at withers, respectively. The material used was from one of the experimental dairy herds (Jälla) of the Swedish University of Agricultural Science. It included recordings on 293 dairy cows with information from 7142 weight occasions and recordings on 275 dairy cows with information of 557 heart girth measurements and 560 measurements of height at withers. The registrations were done during 1993-2002. There was a large variation in live weight between cows in different ages and lactation stages.

Today the individual ventilated cage system (IVC-system) is a commonly used housing system for mice in research facilities. IVC systems have HEPA- filters and are designed to control both supply and exhausted air at cage level, as well as temperature and relative humidity in the cages. This creates an optimal environment for the mouse and at the same time a protection against the risk of cross-infection between cages and the outside environment. The aim of this study was to evaluate the health and welfare of breeding females and pups of two different strains of laboratory mice (NMRI nude mice and C57BL/6N) in three different kinds of IVC-systems; Arrowmight, Allentown and Tecniplast. The NMRI nude (Nu) females gave birth to 18 litters in Allentown, 16 litters in Arrowmight and 15 litters in Tecniplast.

Claw diseases are common diseases in modern dairy production. They are painful for the cow and costly for the producer. Differences in the prevalence of claw disease depending on housing system have previously been observed. This raises the question if there are genotype by environment (GxE) interactions for claw diseases in different housing systems. To investigate this claw trimming records for Swedish Red dairy cattle (SR) and Swedish Holstein cows (SH) were retrieved from the Swedish Dairy Association.