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15 Uppsatser om Longevity - Sida 1 av 1

What traits make Swedish dairy cows survive?

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.

Avel för hållbarhet och livslängd hos köttdjur

The purpose of this literature study was to investigate the possibilities to improve Longevity and stayability of beef cattle with breeding. The breeding goal for beef breeds is to produce animals with high capacity for growth and good feed efficiency. Longevity and sustainability are two important features to include in the breeding goal. If Longevity is increased each cow can produce more calves and the number of female calves used for recruitment can be reduced and only the best heifers need to be selected for breeding. The benefits of longer life is that it lowers the costs of recruitment animals, it increases the number of young animals that become available for slaughter, and it increases the proportion of high producing animals in the herds.

Överlevnadsanalys och avyttringsorsaker - för ackordhäststiftelsens hästar 1967-2012

Few scientific studies have studied the subject of Longevity among horses over a longer period of time. The knowledge about the Swedish riding school horse population concerning injuries and diseases is insufficient. Generally speaking, riding school horses in Sweden have a more undiversified way to work and work more hours in the arena compared to privately owned horses that have more variety in their possible use. Statistical data from the insurance company Agria have shown that horses in riding schools and education facilities have 22 % higher risk to use their veterinary insurance and 79 % higher risk to be put down and use their life insurance, compared to horses in private care. To create an increased understanding for Longevity is it important to have knowledge about the different causes of culling. The aim with this study is to increase the knowledge and enable problem solving within the subject of Longevity, median length of life and causes of death.

Uppfödning av gyltor till hållbara suggor

Half of Sweden?s 140 000-150 000 sows are culled and replaced by 75 000 gilts annually. Culling of old sows is necessary and allows new breeding material to enter the herd. However, many of the culled sows are young, and have not yet become profitable at the time for culling. Therefore, it is an important question for the pig industry, how to raise gilts to sows with a high and sustainable production level.

Predicting spawning bed erosion and longevity : a case study in tributaries to river Vindelälven, northern Sweden

Timber floating operations in Scandinavia during the 19th and 20th centuries has contributed to severe negative impacts on riverine ecosystems. Increase in water velocity and lack of stream bed heterogeneity as a result of stream channelization lead to increased bed load transport. Since availability and recruitment of new suitable spawning substrate in Scandinavian watercourses is sparse, spawning habitats for salmonids has become a scarce commodity. Lately, increasingly more attention has been given to the recreation and improvement of brown trout (Salmo trutta) spawning habitats in restoration projects. While much of the research on spawning habitat has been focused on evaluation of the influence that the constructed spawning grounds have on fish populations, few studies have been conducted to evaluate the persistence of these constructions over time. I evaluate erosion of constructed spawning beds as an effect of sediment transport attributable to water discharge.

Interdependence between seed age and aerated steam treatment intensities

Aerated steam treatment is a modern and environmental friendly method for seed borne fungus sanitation, mainly used on cereals. The method involves exposure to heat and high humidity, factors which are known to induce a fast ageing of seeds, thus resulting in reduced storability. This thesis clarifies the interdependence between seed age and the aerated steam treatment intensities. Two studies were carried out in this thesis. In the first study the storage Longevity of seeds treated with aerated steam was examined. The second study investigated the shelf-life of the pre-tests used to determine the aerated steam treatment tolerance of a seed lot, by testing the treatment tolerance of seeds aged prior to the treatment.

Rengöring, desinfektion och förvaring avendoskop i djursjukvården

With a starting point in the legislation for organic production set up by the Swedishcertification organization KRAV, the reasons to why these regulations are important isexplained and how pigs are affected by these rules. The study also shows how well the pigscope in the organic environment considering the origin of the genetic material; from theconventional pig population. The conclusion is that pigs do function fairly well in the organicproduction environment and the traits affecting their functionality involve: motheringabilities, strong legs, good meat quality, good sow durability and Longevity, capacity to eatmuch roughage and dark skin color. There are however still many ways of improving theorganic population of pigs to make them more adjusted to the organic environment; forexample different traits brought into the breeding goals and the choice of good parent animals..

Is the modern pig suited for organicproduction environments?

With a starting point in the legislation for organic production set up by the Swedishcertification organization KRAV, the reasons to why these regulations are important isexplained and how pigs are affected by these rules. The study also shows how well the pigscope in the organic environment considering the origin of the genetic material; from theconventional pig population. The conclusion is that pigs do function fairly well in the organicproduction environment and the traits affecting their functionality involve: motheringabilities, strong legs, good meat quality, good sow durability and Longevity, capacity to eatmuch roughage and dark skin color. There are however still many ways of improving theorganic population of pigs to make them more adjusted to the organic environment; forexample different traits brought into the breeding goals and the choice of good parent animals..

Klövform och klövsjukdomar hos intensivt uppfödda köttrastjurar :

The top selection of Swedish beef bulls are evaluated yearly by Svensk Köttrasprövning AB at Gismestad. The bulls are selected from six different breeds; Angus, Blonde d´Aquitaine, Charolais, Hereford, Limousin and Simmental, and are kept on straw bedding apart from a concrete alley in front of the feeding area during the six months of evaluation period. The bulls are evaluated according to their fertility scores, growth, exterior and temperament and the exterior, body posture and claw conformation reflect important qualities for their Longevity. In spite of good values for fertility, it has been noticed in the last years that the fertility results and Longevity have been unsatisfactory and claw and/or bone disorders have been suspected as a contributory cause. Persson et al. (2007) studied breeding bulls from Gismestad and other places, which had been slaughtered due to poor fertility (no pregnancies in the herd during their last year in service).

Den andres bröd : Levnadsrisk utifrån Lee-Cartermodellen

Under det gångna århundradet ökade den förväntade livslängden avsevärt såväl i Sverige som i övriga världen. 1900-talets förbättrade livslängd drevs inledningsvis av en minskad barnadödlighet medan de senare årtiondena kännetecknades av minskad dödlighet i höga åldrar.En åldrande befolkning innebär ökade krav på sjukvård, äldreomsorg och inte minst pensionssystem. Pålitliga prognoser för vår framtida livslängd behövs för att beräkna de resurser som nämnda verksamheter kommer att ta i anspråk och utgör förutsättningen för en rättvis prissättning av försäkringsprodukter med levnadsrisk.Lee-Carter-modellen är en av vår tids tongivande modeller för mortalitetsprognostisering. Modellen används här för att göra livslängdsprognoser utifrån svenska mortalitetsdata; prognoserna jämförs sedan med observerade utfall.Mot bakgrund av resultatet diskuteras levnadsrisk med fokus på pensioner.Inte oväntat presterar prognoserna ingen felfri bild av verkligheten och prognosfelet varierar i storlek mellan skattningarna; att använda dem som underlag för pensionsberäkningar hade i förlängningen varit ohållbart. Exemplet illustrerar på samma gång vår osäkerhet inför framtidens livslängdsutveckling och svårigheten i att prognostisera den..

Inverkan av utfodringsnivå och miljö på reproduktion och hållbarhet hos rekryteringskvigor :

This study is based on an earlier interdisciplinary study made by Redbo et al., (2000), Extensive cattle production systems ? out wintering, which lasted over two winters, 97/98 and 98/99, with two groups of heifers indoors and two groups of heifers outdoors raised in different environments, indoors or outdoors during their second winter. Both indoor and outdoor heifer groups were fed grass silage ad libitum throughout the experimental period that lasted from October until May. The objective of this study was to evaluate the long term effects of being raised in these two environments. This study includes data collected during the period lasting from the start of the experiment of Redbo et al., (2000) until the heifers had calved a second time and the results mainly deal with the performance of the animals after the experiment during their first two calvings and their first lactation.

Är Leviathan giftig? : Autonomi och repression som förklaringar till regimskillnader i förväntad livslängd

During the last decade a number of studies have been published that investigate how the most fundamental aspect of political organization, the regime type, affects population health. The results unanimously show that citizens of democracies live longer and healthier lives than citizens of non-democracies. Many explanations for this have been suggested, among these are that democracies redistribute more and invest more in salutogenic resources, and that the tendency of dictatorships to control the media negatively affects the ability to spread information crucial to public health. When these mechanisms are controlled for, however, it turns out that democracy has a large residual correlation with for example life expectancy, which suggests that other mechanisms are also involved.In this paper two new mechanisms regarding the possible psychosocially mediated health effects of the regime type are investigated, namely political repression, and the possible negative effects this might have on the levels of chronic stress, and autonomy, which connects to a large previous literature in social epidemiology. In the paper an ecological cross-country design is used and country-level data, provided mainly by the World Bank and Freedom House, is analyzed with a simple multiple OLS-regression model.

Metabolit- och hormonnivåer som tidiga markörer för fruktsamhet och produktionsstörningar hos mjölkkor

During the last decades the fertility of dairy cows has declined in the same rate as the milk yield has increased. This is a result of the negative genetic correlation between milk yield and fertility, failure to show estrous signs and metabolic problems in the cow. The purpose of this review was to investigate the function of metabolites and hormones as markers for disturbances in fertility, health and production in the dairy cow. There are several metabolites that are suggested to indicate the cow?s energy balance.

New registrations in Swedish beef cattle breeding - with focus on temperament and cow weight

In today?s genetic evaluation of Swedish beef cattle, mainly traits that are directly related to productivity are measured. However, other traits, such as temperament and mature cow weight affect the economy of the farmer, as well as the welfare of the animals. This thesis evaluates possible ways of measuring new traits, with focus on temperament and mature weight of suckler cows. The goal is to examine the possible benefits of including these traits in the Swedish breeding scheme.

Livslängden hos kyllagrade spermier vid artificiell insemination hos häst - kan den förlängas?

Över 90 % av betäckningarna inom Avelsföreningen för svenska varmblodiga hästen (ASVH) skedde med artificiell insemination (AI) år 2011. AI har många fördelar i avelsarbetet då hingsten inte behöver vara på plats när stoet brunstar, möjligheten att välja bland både nationella och internationella hingstar ger en stor valmöjlighet för stoägaren. I Sverige samlas sperma från hingstarna normalt sett tre gånger i veckan genom upphopp på en fantomhäst där ejakulatet samlas i en artificiell vagina. Trots mycket forskning är det fortfarande ca 20 % av hingstarna som lämnar spermier som inte lämpar sig för frysning. Innan nedkylning centrifugeras seminalplasman bort eller späds ut för att reducera inverkan på spermierna. Seminalplasman har positiv inverkan på spermierna vid naturlig betäckning men kan ha negativ inverkan på spermierna under lagring.