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859 Uppsatser om Genetic parameters - Sida 2 av 58
Förekomsten av den genetiska varianten laktapersistens hos neolitiska grupper från Öland : The contribution of the genetic variant Lactase persistence among Neolithic people from the Baltic island Öland in Sweden
This study deals with the contribution of the genetic variant lactase persistence among Neolithic people from the Baltic Island Öland. Skeletal remains from twelve individuals went through DNA sequencing in order to find the mutation that allows adult individuals to digest milk sugar. The twelve individuals were chosen from two different Neolithic sites, where the archaeological and isotopic data suggest that the individuals from Köpingsvik were hunters and gatherers and the individuals from Resmo were early farmers. The individuals with the genetic variant lactase persistence can be described with selection and genetic flow. Only five individuals produced results and the mutation was found in two of the subjects. All the individuals who were successfully sequenced came from Resmo, whereasno individuals from Köpingsvik yielded any results.
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).
Kalvningsintervall hos svenska köttkor : finns det genetisk variation som kan användas i avelsarbetet?
The Swedish beef cattle population is growing when the dairy cattle become fewer. The fertility of the beef cows is important for the profitability in beef cattle production. Today there is no genetic evaluation for female fertility in Swedish beef cows. The purpose of this study was to see if calving interval can be used in the genetic evaluation as a measure of female fertility in beef cows. For this purpose the variation in calving interval for beef cows of different breeds and ages registred in KAP was studied.
Arvets betydelse för mjölkkors beteende :
It becomes more important to consider different behaviour traits in the selection for dairy cows to be suitable in the production systems of today. The purpose of this investigation was to study the genetic background to behavioural traits and the heritabilities for temperament, rank order, aggressiveness, feeding behaviour and for learning behaviour. Moreover, the genetic correlations to other traits were studied. To be included in a breeding programme a trait needs to have enough genetic variation, a moderate to high heritability or to be correlated to another measurable trait. Behaviour is a quantitative trait affected by many genes and the environment.
Utvärdering av vibrationer inom vattenkrafts normer
The International Organization for Standardization (ISO) proposes vibration standards for the evaluation for machine damage due to vibration in rotational machines, where some vibration parameters are given to measure the vibrationgrade. This work evaluates the relevance of the vibration standards in hydro plants that are proposed by the ISO, and also investigates if there are methods used in other countries could have greater importance. Through statistical analysis of collected data we got a better understanding of relation among different vibration parameters, and also the importance of correct choice of the parameters for the evaluation of vibration. We have found that the vibration standards available today in hydro plants are not reliable for the judgment of vibration?s grade.
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.
Privatiseringen av de växtgenetiska allmänningarna : Konsekvenserna av regimkomplexet kring växtgenetiska resurser för bönders rättigheter och matsäkerhet
This thesis discusses the global regime complex concerning the management of plant genetic resources for food and agriculture, and how different regimes concerning these resources cooperate or stand in opposition to each other. Because of changes in US patent law and the establishment of TRIPS, patent claims over plant genetic resources has increased dramatically globally. This, amongst other things, in turn has lead to the development of CBD which in turn lead to the creation of access and benefit laws in many countries. To create a free flow of genetic resources for food and agriculture the ITPGRFA, with its multilateral system, were negotiated. The aim of this thesis is to investigate which consequences the regime complex concerning plant genetic resources for food and agriculture can have on the rights of small farmers, agricultural research and food security in the global South.
Bevarande av de svenska lantraserna, populationsgenetiska och molekylärgenetiska metoder
Today?s community requires an increase in food production. Animals are today bred so that they produce more than their ancestors did. Production has been the most important and breeds with the highest production levels have therefore become popular. Many of the old local breeds have become extinct or are about to become extinct because of this trend.
Genotype by environment interactions of claw health in Swedish dairy cattle in tie stalls and loose-housing
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.
Genetic study of cryptorchidism in Swedish Icelandic and Standardbred horses
Samodling är en odlingsmetod som kan användas för att förbättra dagens odlingssystem. Metoden innebär att två eller flera kulturer odlas tillsammans under en större del av växtsäsongen. Samodling kan användas på flera olika sätt för att förbättra odlingsförhållandena för antingen
huvudgrödan eller hela odlingen. Den har en bevisad effekt på olika skadegörare och kan minska angreppen i odlingen. Samodling kan även användas för att minska ogrässpridningen, förbättra mikroklimatet, samt öka
antalet maskar och naturliga fiender i odlingen.
Genetiska och epigenetiska samband mellan näringsförsörjning och fertilitet hos mjölkkor
The dairy cow?s ability to resume estrus after calving and to conceive is affected by their metabolic status after calving. For high yielding cows there is a high risk that the feed intake will not be sufficient to cope with the increased energy demands after calving, and the cow will end up in a state of negative energy balance. Energy balance can be measured in various ways, for example by body condition score or by plasma concentration of several metabolic hormones and metabolites. After calving, endocrine pathways stimulate tissue mobilization; insulin signaling is blocked, the concentration of insulin-like growth factor-1(IGF-1) and leptin decreases, and the concentration of growth hormone (GH) increases.
Uppdatering av båtnadskalkyl med hänsyn till nya faktorer :
Sweden have 419 000 km road in the country and about half of these roads is forestroads. The forest road net most important mission is to make it possible to deliver wood from the forest to the industries. With a raw material that is spread over a large area the road network is important. Each year has the forest road network been extended with about 1 700 km new roads. To decide if a new road is to be built different forest road cost estimation models has been used.
Felaktig alternativ splicing: Vissa mutationer i BRCA1, BRCA2, ER? och ER? är starkt förknippade med bröstcancer
Alternative splicing is a process that partly rejects the common definition of a gene ? that one gene codes for one specific protein. By variable combination of coding regions (exons) and exclusion of non-coding regions (introns), formation of several different mRNA-transcripts, and consequently several different proteins, can derive from the same gene. Alternative splicing is an important condition for the development of complex life forms, but it is also a highly sensitive process and inaccurate splicing is the cause of approximately 15 % of mutations that cause genetic diseases. This article presents four genes, BRCA1, BRCA2, ER? and ER?, and inaccurate splicing of these genes increases the risk of developing cancer, particularly breast cancer and ovarian cancer.
Inverkan av transgena grundstammar på fruktkvaliteten hos icke-transgena äppelsorten ?Jonagold?
Gene technology has become more and more attractive in plant breeding during the last twenty years. This is probably because it can readily improve the existing commercial cultivars that have only one or a few drawbacks by modifying one or a few genes without changing the main genetic constitution. In this regard, gene technology is more effective than conventional breeding.The aim of this project was to analyze the fruit quality of the non-transgenic apple scion ?Jonagold? grafted on non-transgenic and rolB-transgenic apple rootstocks. The rootstocks used were M9-rolB1, M9-rolB2, M26-rolB and non-transgenic controls M9 and M26.
Stabilisering av process
Calesco Foil AB is a manufacturer of thin flexible circuits for heating or electric conduction.The plant is located in Kolbäck, Sweden.One of the company?s products, the conducting polymer pasta is in present situationunpredictable. Unpredictable in the way that the same type of heater shows differentresistance, depending on which time they have been produced. The desired repetitivelyprocess is almost non-existing.The aim of this master thesis is to primary identify those parameters that effects theresistance, observe and if possible to perform tests on them. The results from this analysisstand as base for recommendations to achieve a repetitive and standardized printing process.The results and the observations from the tests indicate that a repetitive process is possible toachieve.