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160 Uppsatser om Bee mortality - Sida 3 av 11
Predation som selektiv kraft bakom differentiering av populationer av sötvattensgråsugga, Asellus aquaticus
Predation is a strong dective force on invertebrate prey. Asellus aquaticus differs in pigmentation reed and submerged vegetation habitats in lakes. Light pigmented individuals al vegetation dominated by Chara sp. while dark pigmented individuals dominate in the reeds. These differences have been hypothesized to result from background matching.
Do 25 years old skid tracks restrict growth and survival? : a study on growth conditions for the planted regeneration in a rainforest rehabilitation project
The rainforests of the world are important not only to the countries in which they grow but to the world as a whole. They influence oxygen and water circulation as well as carbon sequestration which in turn affect global radiation and global warming. The forest also have great value and in Malaysia as in many other tropical countries large volumes are harvested which leaves great areas of degraded forest with little growth and biological diversity. Due to their low financial value these forests are often transformed and used for other purposes than forestry such as oil palm plantations.
The trees are often transported out of the forest using large bulldozers. They are heavy which causes compaction of the forest floor and during transport the top soil layers are moved to improve mobility.
Effekt av ACE-hämmare på incidens av hjärt-kärlsjukdom och mortalitet hos diabetiker typ 2 samt av diabetes hos hypertonipatienter.
Background: Diabetes mellitus is a chronic disease that manifests as an increased level of glucose in the blood. According to the World Health Organization (WHO), 347 million people have diabetes worldwide. In year 2004, 3.4 million people died from the consequences of high blood glucose. In the Swedish population the prevalence of diabetes is estimated to 3-4 %, out of which 85-90% are Type 2. Among senior citizens a prevalence of diabetes is seen in Sweden up to 14 - 15%.
How strain and production system effects chicken welfare and quality in meat : a literature review
There are several reasons why organic chicken production is scarce in Sweden. Lack of slow growing (SG) strains combined with higher production costs, lower meat-yield and uncertainty of consumers? willingness to pay seems to be the main reasons. EU-legislations imply use of indigenous slow- or medium growing strains in organic production, nevertheless, fast growing (FG) broilers are often used due to their effectiveness. Increased consumption of processed food creates a market for conventionally rearing of very heavy broilers.
Resistenta rapsbaggar :
Oilseed rape crops are an important in southern Sweden because of the high intensity
of wheat growing. Pollen beetles are the most important pest in oilseed rape and
causes often economic losses. Therefore it?s of great importance that we can control
the population density, e g by using insecticides if necessary, to avoid mayor yield
losses.
In year 2000 pollen beetles were numerous in the province of Östergötland. The
farmers sprayed with insecticides several times, but with low effects on the beetles.
Field trials and laboratory experiments showed that pollen beetles had developed
resistance against pyrethroids.
Trädens utveckling efter att de har lämnats som naturhänsyn : tillväxt, mortalitet och strukturell förändring 6-18 år efter avverkning
Today green tree retention, together with leaving dead wood, is a common practice with the aim to reduce negative impacts on biodiversity and environment due to clear-felling. To better understand whether this conservation practice also makes a long-term difference, it is important to know what happens to these trees after harvest. Few studies have made an assessment of what happens to retention trees over a longer time period. In this study I inventoried retention trees that were left at clear-cuts six, twelve and eighteen years ago. I carried out a re-inventory of 57 retention patches (divided into free-standing tree groups, small swamp forests and edge zones) and free standing dead trees, spread over 25 previous clear-cuts in central Sweden.
Föräldraledighetens påverkan på mäns hälsa. En litteraturbaserad studie om sambandet mellan pappaledighet och hälsa utifrån riskbeteende och maskulinitet.
Introduction: Although life expectancy had increased in Sweden for many decades and several health problems had diminished over time, there was no change in men's risk behaviour regarding for instance high alcohol and tobacco consumption. Many of the gender differences in health that existed in society explained were due to power structures and beliefs about behaviour based on gender; a social construction that resulted in the relatively high valuation of men with a more masculine behaviour. Aim: This literature review aimed to study and identify the scientific knowledge regarding paternity leave and its impact on men's health. Method: A literature- based study design was used and the material consisted of peer-reviewed articles from which six themes were identified: alcohol, tobacco, stress, isolation, social support and mortality risk. Results: Divided into three parts, the results described the socioeconomic background of the men who took paternity leave, as well as the impact of paternity leave and masculinity as an impact on men's health.
Tillskottsutfodring av smågrisar under digivningsperioden :
Weaning is one of the most critical events in the piglet production with problems such as growth check and post-weaning diarrhea as a result. The lighter the piglets are when the growth check occurs, the harder they have to get back to normal growth rate. Creep feeding of piglets is used to reduce the problems by increasing the weaning weight and adapting the digestive tract to a starter diet. Hodge (1974) showed that the sow?s milk can not provide enough nutrients for maximal growth rate.
Val av tidpunkt för markberedning vid naturlig föryngring under skärm av Pinus sylvestris i Svealand : Timing of scarification when using natural regeneration in seed tree stands of Pinus sylvestris in Central Sweden
This thesis is built on a field study that was carried out in two seed-tree stands near by Götbrunna in Uppland, Sweden. The aim was to examine if scarification carried out in spring time could generate a more dense seedling establishment when using natural generation, than scarification carried out in autumn. It was also investigated whether there were differences in mortality the first season between the two plot-types. Plots were established block-wise with 50 blocks (pairs) on each site. The spring scarification was made with a hoe during 22-23 of April.
Piglet mortality in commercial piglet production herds
Dödfödda grisar och smågrisdödlighet under diperioden leder till både produktionsförlust och innebär dessutom försämrad djurvälfärd. Förluster orsakade av dödfödslar, smågrisar som kläms ihjäl av suggan och som svälter ihjäl kan förebyggas genom god skötsel, bra djurstallar ochavelsurval. För att lyckas med detta krävs att riskfaktorer för smågrisdödlighet kan identifieras.Syftet med den här studien är att undersöka variationen i förekomsten av dödfödda smågrisar och dödligheten under digivningsperioden beroende på kullnummer, kullstorlek, säsong och besättning. Ett andra syfte är att fastställa om det finns någon upprepbarhet för suggor vad gällerförekomst av dödfödda smågrisar. Data erhölls från fyra kommersiella grisbesättningar, belägna i centrala Sverige, som använder sig av besättningsövervakningsprogrammet ?PigWin Sugg?.
Hundens parvovirus : patologi och riskfaktorer
Canine parvovirus is associated with two disorders: enteritis, which is common, and myocarditis, which is rare. Prominent clinical signs of parvovirus enteritis are vomiting, diarrhea and rapid dehydration. Canine parvovirus type 2 (CPV-2) is very contagious. When CPV-2 first emerged it had high rates of mortality, but later studies have shown that most infections are self-limiting and do not require veterinary care. Mortality rates vary greatly, and therefore it is important to determine risk factors for developing severe canine parvovirus enteritis.
Avledning av öringsmolt (Salmo trutta) från turbinintag
Vattenkraftstationer, med dammar och turbiner, utgör hinder för nedströmsvandrande smolt. Syftet med denna studie var att undersöka turbindödligheten för öringsmolt (Salmo trutta) vid två kraftstationer, de befintliga ytlänsarnas avledningseffekt och om effekten kunde förstärkas genom mörkläggning i form av övertäckning av kraftkanalen med en presenning vid turbinintaget. Utöver detta var avsikten även att undersöka om det fanns något samband mellan smoltgrad och smoltens förmåga att förflytta sig mot havet. I Emån i Småland fångades 46 öringsmolt som radiomärktes och sattes ut vid två kraftstationer och pejlades dagligen i sex veckor. Det var en större dödlighet vid den övre stationen än vid den nedre.
Akut hjärtinfarkt : En litteraturstudie om patienters emotionella upplevelser vid en akut hjärtinfarkt
Background: Heart ischemia is a disease affected by behaviour, lifestyle and heredity. The disease is more common in the western world and the number of those who suffer increases. The mortality has reduced thanks to that medical resources and knowledge have approved. Purpose: The purpose of this study of the literature was to find out what patients experienced emotionally at an acute heart attack. Methods: A study of literature where scientific articles has been refereed and analyzed, then resulted into five categories presented in the result.
Outbreaks of African swine fever in domestic pigs in Gulu district, Uganda
The demand for animal products has increased in the last decades, especially for poultry and pork. Pork production has increased drastically globally, and also in Uganda. Thirty-one percent of Uganda´s population lives in poverty. Pig production is believed to play a crucial role in poverty alleviation, because of the ability to convert low quality feed into high quality protein together with high reproductive potential.
African swine fever (ASF) is a lethal disease of domestic pigs often characterized by haemorrhagic fever and with mortality rates up to 100%. The disease is endemic in most sub-Saharan countries and since 2007 in the Russian Federation and Caucasus area.
Utveckling av gran, Douglasgran, bok och tall under skärm av hybridlärk :
?Development of Norway spruce, Douglas fir beech and Scots pine with a larch
shelter wood? is a report written by Per-Olof Magnusson. The thesis is a
compulsory part of forest engineer program at ?Skogsmästarskolan?, SLU,
Skinnskatteberg, Sweden.
The purpose of this report is to describe and evaluate an experiment with hybrid
larch (Larix x eurolepis) as shelter wood, and different tree species growth and
survival depending on the density of the shelter wood. The experiment is
conducted by southern Swedish forest research centre, faculty of forestry, SLU in
Alnarp.
The hybrid larch ought to be an interesting alternative to birch (Betula sp.) as
shelterwood on suitable sites in southern Sweden.