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133 Uppsatser om Populations - Sida 2 av 9
Habitat diversity and composition among growing wild boar (Sus scrofa L.) populations in Sweden
The wild boar (Sus scrofa L.) has expanded across Europe and Sweden in the last decades. It is a generalist species which utilizes a variety of habitats, and its presence has been shown to have both positive and negative effects for people and the landscape they are in. The abundance and increase of wild boar has previously been shown to differ between counties in Sweden, but there have been few explanations as to why.
In this study, I investigated correlations between the per capita rate of change (r) among wild boar Populations in Sweden and a variety of different habitats on the county level. I also investigated if fragmentation per se or in certain habitats could be associated with the wild boar?s per capita rate of change.
My results show that fragmentation/diversity per se was not correlated with wild boar r.
Aquaculture : animal welfare, the environment, and ethical implications
The aim of this review is to assess the ethical implications of aquaculture, regarding fish welfare and environmental aspects. The aquaculture industry has grown substantially the last decades, both as a result of the over-fishing of wild fish Populations, and because of the increasing consumer demand for fish meat. As the industry is growing, a significant amount of research on the subject is being conducted, monitoring the effects of aquaculture on the environment and on animal welfare. The areas of concern when it comes to animal welfare have here been divided into four different stages: breeding period; growth period; capturing and handling; and slaughter. Besides these stages, this report includes a chapter on the current evidence of fish sentience, since this issue is still being debated among biologists.
Bayesiansk klassificering av ursprung för fångster av sill
Sammanfattning I september 2008 fångades 311 juveniler (unga individer) av arten sill (Clupea harengus) in vid fyra olika områden på den svenska västkusten; Råssö, Hunnebo, Askerö- och Gullmarfjorden. Genetiska, kemiska och morfologiska data (längd och vikt) samlades in i syfte att bestämma vilka populationer de härstammade ifrån. Fångster av sill är så gott som alltid av blandat ursprung eftersom individer bara samlas i de populationer de stammar ifrån vid den tid på året då det är dags för parning (lek). I den här uppsatsen klassificerar jag juvenilerna till tre regioner i vilka populationerna ingår, genom att jämföra de data som samlats in från juvenilerna med motsvarande data i en stor databas över populationer i Nordsjön, Skagerrak, Kattegat och Östersjön samt med ytterligare en population, Risør, som inte ingår i denna databas. Data om populationerna kommer från samples och de sanna Populationsparametrarna (dvs.
Zoonotic respiratory infections and great ape conservation - an emerging challenge
The conservation of great apes faces many challenges, one of which is the threat of infectious disease outbreaks. Zoonotic transmission of respiratory diseases from humans to wild great apes has recently been confirmed. Since respiratory disease is one of the major causes of
death in both gorillas and chimpanzees, this gives reason for major concern.
Little is known about the risks of disease transmission from humans to great apes in natural environments, and there is a need for systematic risk evaluation. Researchers, conservation staff and tourists spend time in very close proximity of wild great apes, sometimes during
long time periods, which poses a potential risk of disease spillover. However, the presence of researchers and tourists has been shown to decrease the risk of poaching, making the matter increasingly complex.
Viltets inverkan på vegetationsutvecklingen i en Sydsvensk skogsföryngring :
Herbivore impact on the Swedish forest has under a long time been a common subject of
debate. There are many different opinions depending on what direction the forest owner has with his/her forest. Populations of moose and roe deer have increased significantly in Sweden during the last decades. The purpose of this study is to get a full picture of the herbivore impact on the regeneration areas. The field work was done once a year for seven years (1999?2005).
Metodikstudie av trollingfisket i Vänern : Jämförelse av fångstrapportering mellan intervjuer och enkäter gjorda på trollingfiskare samt vädrets påverkan på ansträngning
There are five endemic Populations of migratory Atlantic salmon (Salmo salar, Salmonidae) and brown trout (Salmo trutta, Salmonidae) remaining in Lake Vänern, whereof two are salmon and three are trout. There is one population of each species in Klarälven, also one of each in Gullspångsälven and there is a population of trout still remaining in Tidan River. Since the beginning of the 20th century endemic Populations of salmon and trout have either vanished or declined dramatically due to the construction of hydropower in the rivers around the lake, and still today the future of the remaining Populations remains uncertain. To manage salmonid fishes effectively more knowledge of their ecology throughout their different life-stages is needed. A large part of the Lake Vänern salmonoids lives are spent in the lake, where a mayor mortality factor is recreational fishing, especially angling.
Differences in host plant preferences and olfactory physiology between populations of the moth Spodoptera littoralis established in Egypt and Benin
This study was made to compare and distinguish any differences in olfactory recognition and
host plant adaptation between two strains of cotton leaf worm, Spodoptera littoralis. The
Populations used were established in Egypt and Benin, Africa. The documentation consisted of
information about (1) each of the strains development through the larval stage up to pupation on
diets of cotton, clover and cowpea. (2) Their oviposition preferences as adults between cotton,
clover, cowpea, maize and cabbage. (3) Electroantennographic recordings to quantify any
possible responses to plant volatiles.
Throughout the diet experiments the larvae from the Benin strain showed significantly a better
development between artificial, clover, cowpea and cotton respectively, while the Egypt strain
had significance between artificial, cotton and cowpea/clover as diet.
Also noted was how the strains substantial development of weight differentiated if fed the cotton
diet, followed by the cowpea diet showing that the Benin strain would develop a higher body
mass on a cotton diet as well as on a cowpea diet.
This trend was however switched once the pupal stage was reached, where the Egyptian strain
contained a significantly greater body mass than the Benin strain on the artificial and the Benin
strain a greater on cowpea, which suggests that in the end, the Benin strain develops significantly
better on cowpea while the Egypt strain develops better on an artificial diet.
During the oviposition experiment that both stains showed a clear difference in hierarchy of host
plants considered suitable for oviposition, where the Egyptian strain is significantly more
attracted to clover than the Benin strain.
Also showed with electroantennographic recordings and significant values was the higher
sensitivity the Egypt strain had towards (E)2-hexenal, (E/Z)-b-ocimene, (Z)-3-hexenyl acetate,
Nonanal, (-)-linalool and ?-myrcene when compared to the responses from the Benin strain..
Identifiering av fel i skogliga beståndsregister med hjälp av satellitdata :
This thesis has focused on the possibility to use a satellite image method developed by Metria Mijöanalys to identify stands that are wrongly registered in Holmen Skogs database. The method is only intended for identifying stand with poor descriptions in Holmen?s database that needs to be updated and not for updating the stand information.
The study area is located several km west of Hudiksvall on the borderline between Gävleborgs- och Västernorrlands län. The area is covered by a SPOT image from 2005. By which Metria Miljöanalys has made estimates of forest parameters for all stands in the area, and compared them with corresponding estimates according to the stand database.
En utvärdering av avelsprogrammet mot kronisk hjärtklaffsdegeneration hos Cavalier King Charles spaniels :
Chronic valvular disease (CVD) is the most common cardiac disease in dogs, which account for 75% of all the cardiac cases. Cavalier King Charles spaniel (CKCS) is the most affected breed and it´s 13th times more likely that a CKCS, between the age of 7-10 years, will die or be euthanized for cardiac disease, compared with other breeds. The prevalence has been proven to bee independent of coat color and weight but highly dependent on age and gender in CKCS.
In 2001 the Swedish Kennelclub and the Special club for cavalier King Charles spaniel created a breeding program against CVD in CKCS. In this program dogs are not allowed to breed until 4 years of age and have to have a heart auscultation without murmurs.
Habitat preference and dispersal of a sandassociated beetle, Apalus bimaculatus
Species that have a high degree of specialization and poor dispersal ability can be more prone to extinction than more generalist species and good dispersers. How these species traits affect the viability of Populations is dependent on landscape factors,such as isolation and connectivity. Additionally, interactions between species (e.g. symbiosis), and how these interactions vary spatially and temporally can have a large impact on Populations. When the range and habitat areas of a species continuously decrease, management strategies are often needed if the species shall be able to survive.
Grödans kontra odlingssystemets effekt på frilevande nematoder
Nematodes are perhaps the most common animals in the world. Nematode Populations can reach densities up to several millions per square meter in the soil. There are many factors which affect nematode communities in arable soil with respect to diversity and population size. Factors like tillage, crop, fertilization, nutrient status and moisture in the soil all have an impact on soil biology and in this way also have effects on the nematode community. This study is based on three different parts, soil samples taken in March 2012 and March 2013, soil samples taken monthly during the growth season of 2013 in bare fallow plots and a pot experiment.
Rituellt, traditionellt eller funktionellt : en osteologisk analys och jämförelse av två förromerska gravfält från Skogome i Bohuslän och Smörkullen i Östergötland
This paper concerns a comparative analysis between two pre-Roman burial ground and the cremated individuals buried there, Skogome cemetery in Bohuslän and Smörkullen cemetery in Östergötland. The comparative analysis consists of several parts that concern both cemeteries inner and outer burial customs, and the osteological analysis of a total of 18 cremated invidvidulas. By studying the different parts separately, it has been possible to identify similarities and differences between the two contemporary cemeteries. There are great similarities between the cemeteries, differences were mainly observed in the osteological material relating to the amount of bone in each burial. The smaller amounts of bone in the graves of Skogome also holds a higher degree of fragmentation, but can not be explained by a higher combustion rate than the skeletal material from Smörkullen.
Hägn i skogsbruket :
This survey was made during the autumn of 2002 and the beginning of 2003, on commission
from the National Board of Forestry. The purpose with the survey was to gather experience
and knowledge in the organisation about fencing and this was made through interviews. The
ambition was also to get knowledge from people outside the organisation that have great
experience of forestry and fencing.
The interviews were based on questions that have been composed by the author with help
from the supervisors. The questions were the same to both the personal from the National
Board of Forestry and to the foresters. Interviews were also made with private landowners, gamekeepers, game researcher, the County Administrative Board, the National Road Administration, pole and net retailers and contractors.
The target group for this work is the National Board of Forestry to be forwarded to persons interested in forestry with the ambition to spread knowledge about how to prevent damage on the forest by browsing animals.
The deer Populations are big in the south of Sweden and growing Populations have increased the damage on plantations of broadleaves of the most species.
On the hunt for improvements : possibilities of increasing welfare in captive cheetahs through hunting enrichment
The cheetah (Acinonyx jubatus) is one of the big feline species kept in zoos worldwide. The wild Populations are quite small and therefore the captive population make up an important part of the total population of the world. Although life in the wild is not always easy and a captive environment provides shelter and food it does not come without problems. In captivity cheetahs become chronically ill and also develop stereotypic behaviours. Neither of these are problems in wild Populations and both can be linked to stress in captivity.
Vaccination mot Humant Papillomvirus - vem bör vaccineras?
Background: Infection with Human Papillomavirus, HPV, is one of the world's most common sexual transmitted infections. The virus causes genital warts (condyloma) but certain virus types can cause cancer. The most common cancer type caused by the virus is cancer of the cervix. Nowadays there is a screening program for women between 23 and 60 years of age where Pap smears of the cervix is taken to discover abnormalities at an early stage. Cervical cancer is very common all over the world and this screening program saves many lives, but not in the less developed countries since the screening program is too expensive.