18101 research outputs found
Sort by
Out for a Walk Where the Thoughts Take Flight
Get PDFWhen one wanders in nature, the mind follows the feet and the senses. But at times the mind drifts
elsewhere, traveling great distances or to totally different time periods. These episodes may depict
memories of things that have happened in the past, but they can also invent something new, far into
the future. Crossing a brackish canal over a footbridge, the color of the water catches the eye, and,
perhaps without awareness, the thoughts take flight.
That human thought embarks on such spontaneous “mental time travel” of mind wandering is
intriguing and raises questions about cognitive experience. Advances in methodology investigating
this state have yielded evidence linking mind wandering with creative thinking, involuntary
memory, complex social cognition, mood, and environmental dynamics. Recent work in the field of
environmental psychology has theorized that mind wandering might explain creativity benefits of
nature contact. Other recent evidence has associated mind wandering in outdoor nature with mood
improvements. Yet the phenomenon remains under studied in outdoor contexts.
The primary aim of this study was to develop an ecologically valid methodology to track and
measure moments of mind wandering as they occurred during outdoor nature contact. Its secondary
aim was to test that methodology by describing the unfolding of mind wandering (MW) in one urban
blue-green space. This explorative second phase of the study used qualitative and quantitative data
to understand the phenomenon as it occurred in the space and to assess validity of the new
methodology.
Results revealed that a broad array of mind wandering data could be systematically collected and
assessed using the new methodology. The mind wandered readily for most subjects, spread across
much of the study area. Participants reported that the largest percentage of thought content related
to the present, followed by the past, then the future. Participants reported both verbal and imagerybased
MW episodes concerning both the self and others. Possible relationships between the physical
characteristics of the blue-green space and mind wandering content were identified and discussed.
So too was the relationship between duration of nature contact and frequency of mind wandering.
In-depth qualitative analysis of one participant’s experience illustrated the diversification of
thoughts during the short span of the study period, especially via spontaneous memories. Effects of
thought diversification on emotional valence was highlighted. Finally, methodological reflections
and suggestions for future research are discussed
Där land möter hav
Get PDFFram tills nyligen har verksamheterna i Farehamnen (hamnen i Varberg) flyttat för att göra plats åt den framtida planerade stadsdelen Västerport. Piren Hooken ingår i första
byggetappen av Västerport och ska enligt Varbergs kommun fungera som en offentlig yta och inkludera en ny besöksanläggning. I nuläget finns det varken ett fastställt
program eller ett gestaltningsförslag för den offentliga ytan eller besöksanläggningen. Målet med examensarbetet är att ta fram ett gestaltningsförslag för Hooken samtidigt som processen fungerar som diskussionsunderlag. För att ta stöd i och se över behov,
förhåller jag mig till generella direktiv från bland annat kommunens gestaltnings-
program för piren. Efter samtal med kommunen, platsbesök och studier av skönlitterära texter inom temat hav skapas ett koncept med tre principer som är ledande för gestaltningen av Hooken. Samtidigt som gestaltningsförslaget kan läsas självständigt i arbetet är det även en metod för att undersöka den egna gestaltningsprocessen med fokus på skissandet. För att dra lärdomar av och lyfta fram viktiga stunder under processen
presenteras en samling skisser på en A1-plansch.
I diskussionen lyfts reflektioner kring svårigheten av att dokumentera och förlita sig på kreativa stunder under skissandet. Parallellt nämns både tryggheten i att undersöka olika angreppssätt då ens slutgiltiga val ska upplevas bearbetad, och ansvaret i att utreda fler idéer då första utkastet kanske inte är det bästa för platsen. Vidare diskuteras
landskapsarkitektens förmåga att erbjuda nya perspektiv som eventuellt inte
formulerats av beställaren, det handlar om att lita på sin bedömningsförmåga för att uppfylla programmet. Avslutningsvis lyfts närvaron av lärare fram och att de spelar en stor roll för både arbetet och ens egen utveckling.Until recently, the activities in Farehamnen (the harbour in Varberg) have moved to make room for the future planned district Västerport. The pier Hooken is part of the first construction phase of Västerport and, according to Varberg Municipality, will
function as a public space and include a new visitor centre. At present, there is neither an established programme nor a design proposal for the public space or visitor facility. The aim of this thesis is to develop a design proposal of Hooken while the process
serves as a basis for discussion. In order to find support and look at the needs, I am using general guidelines from the municipality’s design programme for the pier. After conversations with the municipality, site visits and studies of literary texts on the theme of the sea, a concept is created with three principles that guide the design of Hooken. While the design proposal can be read independently in the work, it is also a method for examining the own design process with a focus on sketching. To learn from and highlight important moments during the process, a collection of sketches is presented on an A1 poster.
In the discussion, reflections on the difficulty of documenting and relying on creative moments during sketching are highlighted. In parallel, the security and responsibility of exploring different approaches are mentioned as one’s final choice should feel
processed, and since the first draft may not be the best for the site. Furthermore, the landscape architect’s ability to offer new perspectives that may not have been formulated by the client is discussed, it is a matter of relying on one’s judgement to fulfil the
programme. There is also an emphasis on the presence of teachers, who play a major role in both the work and one’s own development
Sampling of pesticides in water using solid-phase extraction
Get PDFThe aim of this study was to develop a sampling method for pesticide residues in water using solid-phase extraction. A sampling equipment has been assembled constituting of a raft, a filter holder with glass micro fibre filter, and an ENV + solid-phase column connected to a vacuum flask and a pump with reversed function. The equipment can easily be brought out in the field and sampling of a volume of 500-1000 ml can be carried out within 30 minutes. Water soluble and particle bound residues are separated. By using the solid-phase sampling equipment losses of analytes through degradation and adsorption can be reduced and transport of samples to the laboratory is facilitated. The dissolved fraction of a pesticide is captured in the solid-phase column and a pre-washing step of ENV + is generally needed before use but activation of the columns can be excluded. Elution with dichloromethane can be made directly without a soaking step. The particle bound fraction collected on the glass micro fibre filter is efficiently extracted when using Soxtec extraction with dichloromethane/acetone (1:1, v/v). In the beginning of the study focus was on two pyrethroids, esfenvalerate and deltamethrin, since these hydrophobic substances can be difficult to recover from the solid-phase column. When appropriate extraction conditions were achieved for the two pyrethroids 14 other pesticides of different character were introduced in the study to investigate whether the selected extraction methods gave satisfactory recoveries. Adequate results (total recovery between 70 and 130%) were achieved for the following pesticides: atrazine, deltamethrin, diflufenican, diuron, esfenvalerate, ethofumesate, hexazinon, isoproturon, lambda-cyhalotrin, metazachlor, pirirnicarb, propiconazole and simazine. The recovery of terbutylazine exceeded 130% while the recovery of fenpropimorph and metarnitron were lower than 70%. Esfenvalerate, deltamethrin and lambda-cyhalothrin were to a large extent recovered from particles while the major portion of other pesticides studied were retrieved from the water phase
Functional feeding groups of benthic macroinvertebrates in Swedish lakes and streams and the importance of spatial scale
Get PDFMultivariate statistical methods were used to explore the relationships between functional feeding guilds of different macroinvertebrate communities in Swedish streams and lakes.
The most important factor for explaining the composition of functional feeding groups, both in streams and lakes, seemed in Sweden to be geographical position ( e.g. altitude and ecoregion) and local scale factors ( e.g. substrate).
Principal component analysis (PCA) showed that abiotic factors, like stream velocity and geographical position, seemed to be important both in streams and lakes. Like PCA, redundancy analysis (RDA) showed that geographical factors were important for the functional feeding group composition of benthic communities in lakes. Forest in the catchment area and stream velocity were important for the composition in streams.
Using partial RDA, a total of 39.9% for stream data and 44.0% for lake data were explained. The unique variation of local scale factors seemed to be the most important factor to explain the variability of functional feeding groups, both in streams (59%) and lakes (44%), out of the total variation that could be explained.
Stream velocity in streams and geographical position in lakes also showed, in stepwise multiple regression, to be important factors for the functional feeding group composition. The highest adjusted r2-value for stream data was shown by passive filter-feeders (0.44), followed by grazers (0.40), detritus feeders (0.35), shredders (0.30), predators (0.28), and active filterfeeders (0.21). For lake data the highest adjusted r2-value was shown by detritus feeders
(0.54), followed by grazers (0.49), predators (0.27), active filter-feeders (0.29), shredders
(0.27), and passive filter-feeders (0.15).
The abundance of macro invertebrates showed for functional feeding groups in lakes, but not in streams, a tendency of increasing values from north to south in the country. Except for the alpine region, the functional feeding group composition of streams did not vary among ecoregions. In lakes, a significant difference in composition of functional feeding groups occured between the middle and southern boreal regions.
A field study comparing functional feeding group composition and fatty acid contents between arable and forested sites within a single stream was also done. No significant differences in functional feeding group composition were found except for active filterfeeders. Fatty acid composition was similar within, but different among the functional feeding groups analyzed between forested and arable sites
Seroprevalens av felint panleukopenivirus hos domesticerade katter i Maasai Mara, Kenya : ett möjligt hot för smittspridning till vilda djur?
Get PDFFeline panleukopenia virus (FPV) is a highly contagious virus that can stay stable in the environment for a long period of time. The virus can infect both domesticated cats, wild felids, and other wild animals. It has the highest morbidity and mortality rate in new-born and young kittens. The virus leads to viremia and mostly affects the dividing cells in the body, i.e. bone marrow, lymphoid tissues, intestinal epithelium, cerebellum in young animals, retina, and embryonic and foetal cells. Common clinical signs of infection with FPV in adult cats are lethargy, vomiting and diarrhoea. In young or new-born kittens, neurological signs are common. Infection with FPV can vary in its severity, from subclinical to per acute with little to no clinical signs before a sudden death.
This study was conducted in the Mara North Conservancy (MNC) within the nature reserve Maasai Mara in Kenya. Mara North Conservancy holds a large wildlife with lions, cheetahs, leopards, hyenas, zebras, elephants and many more. This study aimed to investigate the sero-prevalence of FPV in domesticated cats in the area and to see if there would be a possibility of transmission of FPV between domesticated cats and wild animals.
In total, 40 cats were sampled, 29 females and 11 males. 85% of the sampled cats had antibodies against FPV. There was a difference in the seroprevalence between genders, 93.1% of the females had antibodies against FPV and 63.6% of the males.
The results of this study showed a high prevalence of FPV antibodies in domesticated cats within the Mara North Conservancy. Theoretically there is a risk of domesticated cats spreading FPV to wildlife in the area, but a combined study that would look at both domesticated cats and wild animals and if they share FPV antibodies with the same genome would be needed to make that conclusion.Felint panleukopenivirus (FPV) är ett mycket smittsamt virus som kan förbli stabilt i miljön under lång tid. FPV kan infektera både tamkatter, vilda kattdjur och andra vilda djur. Nyfödda och unga kattungar har högst morbiditet och mortalitet. Infektion med FPV leder till viremi och påverkar framför allt de snabbt delande cellerna i kroppen, dvs celler i benmärg, lymfoida vävnader, tarmepitel, lillhjärnan hos unga djur, näthinnan samt embryonala- och fosterceller. Vanliga symptom på infektion med FPV hos vuxna katter är letargi, kräkningar och diarré. Hos unga eller nyfödda kattungar är neurologiska symptom vanliga. Infektion med FPV kan variera i svårighetsgrad, från subklinisk till perakut med få eller inga kliniska symtom före en plötslig död.
Denna studie genomfördes i Mara North Conservancy (MNC) som ligger i naturreservatet Maasai Mara i Kenya. Inom MNC finns det många olika vilda djur t.ex. lejon, geparder, leoparder, hyenor, zebror, elefanter och många fler. Studiens syfte var att undersöka seroprevalensen av FPV hos domesticerade katter i området och om det skulle finnas en möjlighet för överföring av FPV mellan domesticerade katter och vilda djur.
Totalt provtogs 40 katter, 29 honor och 11 hanar. 85 % av de provtagna katterna hade antikroppar mot FPV. Det fanns en skillnad i seroprevalensen mellan könen, 93,1 % av honorna hade antikroppar mot FPV och 63,6 % av hanarna.
Resultatet av denna studie visade en hög förekomst av FPV-antikroppar hos domesticerade katter i Mara North Conservancy. Rent teoretiskt finns det en risk för att domesticerade katter sprider FPV till vilda djur i området, men en kombinerad studie som tittar både på domesticerade katter och vilda djur och om de delar antikroppar mot FPV med samma genom behövs för att dra den slutsatsen
Selection of tree quality in urban environments : the impact of tree size on establishment in new plantings
Get PDFEtablering av nyplanterade träd i urbana miljöer kan komma med vissa svårigheter då träden ofta möter tuffa ovan- och underjordiska förhållanden. Detta gäller sådant som vandalisering, torka och bristfällig jordkvalitet. Samtidigt för en snabb etablering med sig många fördelar såsom effektivt nyttjande av resurser, leverans ekosystemtjänster och positiva upplevelser av det rumsliga uttrycket. Syftet med arbetet är att undersöka hur val av storlekskvalitet påverkar nyplanterade träds etablering och överlevnadsgrad samt redovisa för- och nackdelar med val av storlek baserat på plats och situation. Metoden som användes i arbetet var en litteraturbakgrund samt semistrukturerade intervjuer med yrkesverksamma landskapsarkitekter från Halmstad respektive Uppsala kommun. Personerna som tillfrågades hade båda mångårig erfarenhet från kommunal park och gatuskötsel.
Resultatet visade att mindre kvaliteter måste planteras på rätt plats för att komma till nytta och ges en ärlig chans att överleva. Det framkom även att det finns platser där större kvaliteter är att föredra framför mindre, exempelvis där skugga och ekosystemtjänster är viktiga från start. Slutligen argumenteras för att mindre kvaliteter kan komma till nytta vid framtida problem med mer eller mindre frekvent torka. Dess mindre behov av vattning under etablering kan bli ett led i säkrandet av den framtida gröna infrastrukturen.Establishment of newly planted trees in urban environments can present certain challenges as the trees often encounter tough above- and below-ground conditions. This includes vandalism, drought, and poor soil quality. At the same time, quick establishment brings many advantages such as efficient resource utilization, delivery of ecosystem services, and positive experiences with the spatial expression. The purpose of this study is to investigate how the choice of size quality affects the establishment and survival rate of newly planted trees and to present the advantages and disadvantages of size selection based on location and situation. The method used in the study included a literature review and semi-structured interviews with professional landscape architects from Halmstad and Uppsala municipalities. The individuals interviewed had extensive experience in municipal park and street maintenance.
The results showed that smaller qualities must be planted in the right location to be beneficial and given a fair chance to survive. It also emerged that there are locations where larger qualities are preferable to smaller ones, for example, where shade and ecosystem services are important from the outset. Finally, it is argued that smaller qualities can be beneficial in future problems with more or less frequent drought. Their lesser need for watering during establishment can contribute to securing the future green infrastructure
Can precommercial thinning be used to create more diversity after planting spruce?
Get PDFMixed forests will harbour other ecosystem services than a planted coniferous
monoculture. This study used early results from a long-term experiment to examine
if different precommercial thinning treatments can be used to increase diversity in
planted stands of Norway spruce (Picea abies) mixed with high densities of natural
regeneration of birch (Betula spp.).
Precommercial thinning treatments are standard in the Swedish even-aged clear-cut
silvicultural system and are used to shape the future commercial thinning stand.
Three different precommercial thinning strategies were applied as treatments in
planted stands of Norway spruce (Picea abies). Used selection strategies were I)
spruce monoculture with an even diameter distribution and the largest stems, II)
mixed stand with an uneven diameter distribution and only the largest 1/8 of stems,
combined with the smallest trees and III) mixed stand an even diameter distribution
and the largest stems. The treatments were tested with densities of 1200 and 1500
stems hectare-1 after treatment. Investigated parameters after treatment were
quadratic mean diameter, diameter distribution, mixed species ratio and the
development over two years after treatment.
The experiment was established on two sites with three blocks on each site.
Precommercial thinning was performed in 0.08-hectare sized plots with a buffer
zone of 5 m. All trees within the treatment plot were measured directly after
precommercial thinning and two years after treatment, as a part of a long-term
experiment. Measurements were taken by cross-calipering all trees at 1.3 m and
registering tree species. Sample trees were selected from the whole diameter
distribution and used for height measurements.
Results showed that increased stand diversity could be created through a mixed
species strategy in precommercial thinning. The diameter and height distributions
were largely unaffected by treatment. Planted spruce had a larger diameter than the
naturally regenerated birches, which were more slender and less dominant. Overall,
the results were in line with previous studies in southern Sweden. The study was
concluded with practical applications and suggestions for future research
Arbetsmarknadens förväntningar på den nyexaminerade landskapsingenjören : vilka kunskaper är viktiga att få med sig från utbildningen?
Get PDFDet här arbetet är en intervju- och litteraturstudie som ger svar på vilka kunskapsförväntningar som
ställs från arbetsgivarnas sida och hur landskapsingenjörsprogrammet möter dessa förväntningar.
Vilken yrkesroll har en nyexaminerad landskapsingenjör möjlighet att få vid etablering i arbetslivet,
För att ta reda på vilka förväntningarna är, studeras landskapsingenjörens arbetsmarknad,
kvalitativa intervjuer genomförs och jobbannonser studeras genom att identifiera arbetsuppgifter,
önskad kompetens och meriter.
Resultatet är att landskapsingenjörsprogrammet möter arbetsmarknadens förväntningar på ett
bra sätt. Landskapsingenjörsprogrammet kan förbättras för att förbereda studenten bättre för
arbetslivet. Genom mer teoretiska delar såsom projektledning, arbetsledning, juridik och ekonomi
kan studenten förbereda sig mer för att kunna axla rollerna som en nyexaminerad landskapsingenjör
kan få efter sin examen. Dessa yrkesroller liknar projektledare och arbetsledare men får inte
förväxlas med en vanlig utbildning inom projektledning då det är landskapsingenjörens blandade
kunskap inom utemiljö som gör den unik.This paper is an interview and literature study that provides answers to what knowledge expectations
are set from the employers' side and how the landscape engineering program meets these
expectations.
What professional role does a newly graduated landscape engineer have the opportunity to get when
entering working life?
To find out what expectations there are, the landscape engineer's labor market is studied. Qualitative
interviews are conducted and job listings are studied by identifying tasks, desired skills and merits.
The result is that the landscape engineering programme meets the expectations of the labour market.
The landscape engineering programme can be improved to better prepare the student for working
life. Through more theoretical parts such as project management, work management, law and
economics, the student can be more prepared to take on the roles that a newly graduated landscape
engineer can get after graduation.
These professional roles are similar to project managers and supervisers but shouldn´t be confused
with a regular education in project management, as it is the landscape engineer's mixed knowledge
of outdoor environment that makes it unique
A good animal welfare? : a literature study on what can be done to reduce the fear in dairy cows in connection with loading and transport
Get PDFRädda och stressade djur är inte välmående djur. Rädda mjölkkor kan reagera
oförutsägbart och hastigt vilket gör att de kan vara farliga att hantera. Rädsla och stress hos
mjölkkor kan orsaka fysiska skador, materiella skador och ekonomiska förluster. Syftet med denna
studie är att få fram förslag på förbättringar i samband med lastning och transport av mjölkkor,
för att reducera rädsla och stress hos djuren, som i sin tur kan öka djurvälfärden som kan
gynna köttkvalitén, ekonomin och mjölkproduktionen.
Eftersom mjölkkor har intensiva laktationsperioder bör vi göra allt vi kan för att de ska vara så
trygga som möjligt, oavsett om det är i ladugården, på bete eller på en transport. Studien
förklarar också hur rädsla och stress påverkar djuren rent fysiologiskt, samt påverkan på
slutprodukten till exempel köttkvalitet.
Målet med litteraturstudien är att föreslå olika sätt att reducera rädsla och stress hos mjölkkor
vid lastning och transport, med förhoppningen att föreslagna åtgärder sedan kan användas i
praktiken för att förebygga rädsla och stress. Att få lugnare djur är viktigt både ur ett
hållbarhets- och ett etiskt perspektiv.
Sökningar i Google Scholar gav ämnesaktuella artiklar varav 42 valts ut för denna studie och även
andra källor som till exempel Jordbruksverket. Resultatet av litteraturstudien visar att
vid lastning och transport av mjölkkor bör åtgärder tillämpas för att förhindra rädsla.
Min frågeställning och de utvalda artiklarna sammanvävs med forskningen som ger förslag på
åtgärder för att minska rädsla och stress.
Några praktiska lösningar att ta hänsyn till vid lastning och transport för att minska rädsla och
stress var: inredningen bör vara neutral med samma färgskala genom rummen (Ekman 2003; Grandin,
1995), att man behöver ha lugn och utbildad personal (Ceballos et al. 2018) (Boivin 1992)
(Pas et. al 1998) (Silva et. al. 2017), samt bra ljussättning (Grandin T. et. al. 2022) (Phillips
1998) (Penev et. al. 2014). Att minska skuggor och buller (Willson et. al. 2021) och till och med
att ta hjälp av musik (Ciborowska et. al. 2021) kan vara effektivt. Att bilda positiva minnen redan
ifrån födseln är också en åtgärd (Grandin, 2019), samt att ha äldre och lugna mjölkkor
som visar dem yngre hur ”allt går till” (Stenfelt et. al. 2022).
Eftersom djurstallet är utgångspunkt vid en transport bör även detta beaktas när man vill reducera
rädsla och stress hos mjölkkor. I djurstallet bör inredningen vara neutral utan höga ljud.
Inredningen bör ha en enhetlig färgskala och ljussättning bör vara väl genomtänkt med en bra ljusstyrka. Ljussättningen i transportfordonet bör
vara ännu starkare eftersom mjölkkor naturligt rör sig mot starkare ljus.
I diskussionen tas vikten av utbildad personal, anpassad inredning samt andra
förebyggande åtgärder för att minska rädsla och stress hos mjölkkor upp. Jag tycker framtiden ser
ljus ut för både lantbrukare och mjölkkor eftersom minskad rädsla och stress kommer att bidra till
mer välmående djur, en högre mjölkproduktion och bättre köttkvalitet.Frightened and stressed animals are less prosperous animals. Afraid dairy cows can react unpredictable and hastily, which means that they can be dangerous to handle. Fear and stress in dairy cows can cause physical damage, material damage and financial losses. The purpose of this study is to come up with suggestions for improvements in connection with loading and transport of dairy cows to avoid fear and stress in the animals, which in turn could increase animal welfare which can benefit meat quality, economy and milkproduction. Since dairy cows have intense lactation periods should we do everything we can to provide a safety area, regardless of if it is in the barn, on pasture or on a transport. The study also touches on how fear and stress affect the animals purely physiologically, as well as the impact on the product, for example meat quality.
The aim of the literature study is to suggest different ways to reduce fear and stress in dairy cows during loading and transport, with the hope that proposed measures can then be used in practice to prevent fear and stress. Getting calmer animals is important from both a sustainability and an ethical perspective.
Google Scholar searches returned current articles, of which 42 were selected for this study and even other websites such as Jordbruksverket. The results of the literature study show that when loading and transporting dairy cows, measures should be applied to prevent fear. My question and the selected articles interwoven with the research which gives suggestions for measures to decrease fear and stress.
Some practical solutions to take into considerations during loading and transport to reduce fear and stress is; the decor should be neutral with the same colour scale through the entire room (Ekman 2003; Grandin T. 1995), you need calm and educated staff (Ceballos et al. 2018) (Boivin 1992) (Pas et. al 1998) (Silva et. al. 2017). And good lightning (Grandin T. et. al. 2022) (Phillips 1998) (Penev et. al. 2014). To reduce shadows and noise (Willson et. al. 2021) and get help from music (Ciborowska et. al. 2021). To build positive memories already from birth is also a measure (Grandin T. 2019), and to have older and calmer dairy cows that’s shows the way for the younger ”how everything is done” (Stenfelt et. al. 2022).
Since the animal stable is the starting point for a transport, this should also be considered when you want to reduce fear and stress in dairy cows. In the animal stable, the interior should be neutral without loud noises. The interior should have a uniform color scheme and lighting should be well thought out with a good brightness. The lighting in the transport vehicle should be even stronger as dairy cows naturally move towards stronger light.
The discussion addresses the importance of trained staff, adapted furnishings and other preventive measures to reduce fear and stress in dairy cows. I think the future looks bright for both farmers and dairy cows because reduced fear and stress will contribute to more healthy animals, higher milk production and better meat quality
Thiamine deficiency in ruminants : how common are symptoms in Sweden?
Get PDFTiamin är ett vattenlösligt vitamin essentiellt för många djur, inklusive människor. Idisslare producerar normalt tillräckligt med tiamin via mikrober i våmmen, men brist kan ändå uppstå vid särskilda förhållanden. Unga idisslare som ännu inte utvecklat en fullt fungerande våm förlitar sig på tiaminintag via mjölk för att brist inte ska uppstå. Tiaminbrist kan leda till den neurologiska sjukdomen cerebrocortikal nekros (CCN) som kan ge upphov till symtom som ataxi, stjärnkikare, huvudtryck, opistotonus, blindhet och kramper. Orsaker till att CCN uppstår hos idisslare kan vara intag av tiaminaser, tiaminasproducerande mikrober i våmmen eller överdrivet intag av svavel som kan påverka tiaminproduktion och tillgänglighet av tiamin. Diagnosen CCN ställs oftast genom en provbehandling med tiamin. Diagnos kan även ställas via obduktion. Andra symtom associerade med tiaminbrist är nedsatt tillväxt.
Huvudsyftet med den här studien var att undersöka symtomförekomst av tiaminbrist vid svenska idisslarbesättningar (nöt & får). Studien syftade även till att undersöka eventuella skillnader i symtomförekomst mellan djurslagen, åldrar, årstider, produktionstyper och olika geografiska områden. Studien avhandlar främst symtom på tiaminbristorsakad CCN. Andra sjukdomar som kan likna tiaminbristens symtom, inkluderande svavel-inducerad CCN, avhandlas delvis i arbetet. Studien genomfördes som en nätbaserad enkätstudie som besvarades av djurägare eller personer med en övergripande bild av besättningens produktion och sjukdomsläge under en längre tidsperiod. Av de 255 korrekt slutförda svar som inkom representerade 172 fårbesättningar och 83 nötbesätt-ningar.
Enbart deskriptiv statistik genomfördes och därmed ger studien inga statistiskt säkerställda resultat. De resultat som erhållits deskriptivt tyder på att symtomen på tiaminbrist är ovanliga i Sverige, men att de förkommer sporadiskt både på får- och nötbesättningar. Ett fåtal besättningar har uppgett högre symtomförekomst än andra besättningar. Både symtom på CCN och diagnos av CCN förekom oftare på fårbesättningar än på nötbesättningar. Enbart ett fåtal djur med observerade symtom hade diagnosticerats med CCN av veterinär. Symtom på CCN var vanligast hos unga djur mellan noll och två månader samt hos djur äldre än 18 månader. De flesta symtomen observerades under våren. Inga geografiska skillnader i förekomst kunde ses i studien. Studien indikerar på en högre andel kraftfoder till slakt- och ungdjur hos nötbesättningar som observerat symtom jämfört med de besättningar som inte observerat symtom.
Enkätens utformning gav generella svårigheter i arbetet att statistiskt analysera resultaten. Frågorna var baserade på tio års retrospektiv information, något som kan antas ha resulterat i minnesbias och bristande precision i svaren. Dessutom kan förändringar i antal djur och utfodringsmetoder över tid ha påverkat resultaten. För kommande forskning skulle det vara av intresse att undersöka besättningar med mer förekommande CCN-problematik och genomföra en mer omfattande analys av dessa.Thiamine is a water-soluble vitamin essential for many animals, including humans. Ruminants can, via microbes in the rumen, produce enough endogenous thiamine, however deficiency can still occur in ruminants. Young ruminants that have not yet developed a fully functional rumen rely on thiamine intake to prevent deficiencies. Thiamine deficiency can develop into the neurological disease cerebrocortical necrosis (CCN) which can present with the symptoms ataxia, star-gazing, head-press, opisthotonos, blindness and convulsions. Reasons for the development of disease can be consumption of thiaminases, thiaminase producing microbes in the rumen or excess consumption of sulphur. The most common diagnosis tool for CCN is positive response after treatment with thiamine. During a necropsy, changes in the brain of the animal are usually seen. Another symptom associated with thiamine deficiency is decreased growth.
The aim was to investigate the prevalence of thiamine deficiency symptoms in Swedish ruminant herds. The aim was also to analyse variations in occurrence depending on different factors including species, age, season, production types and geographical regions. The study was conducted via a net-based questionnaire and distributed via groups on social media for ruminant owners and corporations involved in the ruminant production industry. The questions were answered by people with an overall picture of the herds production and diseases over a longer period of time. Out of 255 completed questionnaires 172 were representing sheep herds and 83 were representing cattle herds.
Only descriptive statistics were conducted, and therefore the study does not yield significant results. The results suggest that the symptoms of thiamine deficiency are uncommon in Sweden, however they do occur sporadically in both sheep and cattle herds. Only a few herds reported a higher-than-average prevalence of symptoms. Both symptoms and diagnosis of CCN were more common in sheep than in cattle. In both species few of the animals with observed symptoms got a CCN-diagnosis by a veterinarian. Symptoms were most common in very young ruminants and in animals older than 18 months. Most symptoms occurred during spring. No geographical connection between prevalence of symptoms were observed. The study suggests a connection between a higher proportion of concentrate feed given to cattle destined for slaughter and young animals in herds that have observed symptoms, compared to herds that have not observed symptoms.
The study design limited the ability to draw statistically significant conclusions. This is due to both the low frequency of observations of symptoms and that the questions were based on a ten-year retrospective information. This could have affected the results due to recall bias and imprecision in the responses. Furthermore, changes could have occurred in the number of animals in the herd and methods of feeding over time which may have impacted the results. For future studies it would be interesting to deep analyse herds with more than average problems of CCN