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457 Uppsatser om Extended lactation - Sida 1 av 31

Quantification of sleep in dairy cows in three different stages of lactation

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 when sows are group housed during lactation : associations with sow productivity and behaviour

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.

Introduktion av förstakalvare i AMS : en enkätstudie

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.

The effect of social rank on milking and feeding behaviour in automatic milking system for dairy 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.

Genetic variation in dairy cattle claw health traits recorded by claw trimmers

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).

Analys av juverhälsodata från kärnbesättningen Viken :

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.

Studier av mjölkbarhet automatiskt mätt i mjölkningsanläggningar :

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.

Utvärdering av Artificiella Neurala Arkitekturer För Navigering

Den klassiska approachen till navigering innefattar att agenten håller en intern representativ modell av omgivningen. Denna approach har emellertid många nackdelar, speciellt för dynamiska miljöer. En modernare approach är att förlita sig på den faktiska omgivningen istället för en modell av denna. Detta arbete presenterar en undersökning av navigeringsproblemet och hur väl det löses av agenter vars kontrollmekanismer utgörs artificiella neurala nätverk. Tillförlitligheten hos de två neurala arkitekturerna Extended sequential cascaded network och Self-organized recurrent network bestäms genom experiment.

Estimation of heterosis and performance of crossbred Swedish dairy cows

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.

Vid vilken glukosnivå frisätter kor insulin? :

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.

En dekonstruktion i ljud : J.O. Mallanders Extended Play

J.O. Mallander?s Extended Play (1968) is a sound recording, a readymade, of the counting of votes in two presidential elections in Finland, during 1962 and 1968. A voice repeats monotonously: ?Kekkonen, Kekkonen, Kekkonen, Kekkonen, Kekkonen?? Although the Finnish president Urho Kekkonen represents, almost personifies, the politics of the post World War II period in Finland, Extended Play does not explicitly address the political. Rather, as this essay argues, it engages in the discourses of power and politics by providing a temporalization of its fixedness, or what Jacques Derrida terms the proper.Extended Play is, in parallel with Derrida?s critique of western metaphysics, a deconstruction in sound that challenges the state ideologies conveyed in the process of the counting of votes, where the presuppositions of the presence of the voice characterizes the ambiguities of power that Kekkonen?s politics of neutrality represent.Mallander?s readymade emerges as a double of the game theory strategies of the Cold War, a mimetic surplus of the administrative control mechanisms of sound recording.

Ränteavdragsbegränsningsreglerna : Är den svenska skattebasen skyddad?

This thesis treats the extended Swedish rules regarding deduction limitations on interest. The purpose for this thesis is to investigate whether the interest deduction limitation rules have potential to protect the Swedish tax base. The thesis also assesses whether the options presented how the extended rules could look liked had been better to protect the Swedish tax base. Furthermore thin capitalizations rules have been evaluated if this is a better method to protect the Swedish tax base.In 2009 the Swedish deduction limitations rules on interest came in to force to protect the Swedish tax base. Despite these rules companies was still able to avoid Swedish tax and therefore threatened the Swedish tax base.

Samband mellan hull, underhudsfett, levande vikt och fruktsamhet hos SRB och SLB :

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.

Studie av glasfasader för kommersiella byggnader

Den klassiska approachen till navigering innefattar att agenten håller en intern representativ modell av omgivningen. Denna approach har emellertid många nackdelar, speciellt för dynamiska miljöer. En modernare approach är att förlita sig på den faktiska omgivningen istället för en modell av denna. Detta arbete presenterar en undersökning av navigeringsproblemet och hur väl det löses av agenter vars kontrollmekanismer utgörs artificiella neurala nätverk. Tillförlitligheten hos de två neurala arkitekturerna Extended sequential cascaded network och Self-organized recurrent network bestäms genom experiment.

Gruppering av sinkor i stora besättningar

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.

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