| 1. |
- Abraham, Maria Celina
(författare)
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Reproductive biotechnologies in Swedish male alpacas
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Alpacas have become more popular during the last decades. The herds have been built up by importing live animals since reproductive biotechnologies, for example artificial insemination and semen preservation, are not well-developed in this species. A major problem is the viscosity of the seminal plasma which hinders processing or evaluation of the semen. Enzymes have been used to deal with the viscous seminal plasma but they may damage spermatozoa or render them incapable of fertilization. The use of reproductive biotechnologies would permit the introduction of new genetics without the need to import live animals, thus improving animal welfare and reducing the risk of spreading diseases. Therefore, our aim was to improve reproductive biotechnologies to help develop the Swedish alpaca breeding industry. Laboratory techniques were performed to select the best spermatozoa with Single Layer Centrifugation (SLC), in order to improve cryopreservation. These techniques were developed first using bull semen. There was an improvement in sperm quality in the SLC-selected samples, particularly from poor quality semen. In addition, the SLC technique could be modified to process small volumes. Alpaca epididymides were obtained after routine castration for husbandry purposes, with the intention of comparing semen extenders using extracted epididymal spermatozoa. Most of the organs came from pre-pubertal animals and therefore did not contain spermatozoa. Nevertheless, a decision-making tool for alpaca husbandry under Swedish conditions was developed. We suggest a combination of testicular size and body condition score as a tool for decision-making in the selection of potential sires for animal husbandry under Swedish conditions. A phantom was designed and built to collect semen samples in Sweden, and semen collection trials were also performed in Perú. The advantages and disadvantages of different semen collection techniques were evaluated. However, the problem with semen viscosity still has to be solved. Therefore a semen collection method should be established so that semen handling methods can be developed. We conclude that a phantom could be the best method to use for semen collection in Sweden, since it is a fairly simple technique and, as far as we are aware, there are no animal welfare concerns.
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| 2. |
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| 3. |
- Amentae, Tadesse Kenea
(författare)
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Evaluation of supply chains and post-harvest losses of selected food commodities in Ethiopia
- 2016
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Supply chain management practices and losses in food value chains of three major food commodities in Ethiopia (milk, teff and warqe or enset) were evaluated in this thesis. Teff is a cereal, while warqe is a perennial plant from which the food products kocho and bulla are extracted. Teff, kocho and bulla are staple foods for many Ethiopians. In the three case studies, value chain analysis, questionnaire-based loss estimations and Likert scale-based loss factor evaluation were applied. Qualitative and quantitative primary data were collected using a semi-structured survey questionnaire and key informant interviews. The data were analysed using descriptive statistics, Tobit and Probit models in SPSS and Microsoft Excel software. The study identified major chain actors and losses at each stage of the food supply chains. In the milk chain, estimated losses were 3.35%, 5.46%, 2.45%, 0.95%, 1.23% and 0.88% at producers, cooperatives/union, wholesalers, retailers, processors and catering institutions, respectively. In the teff chain, estimated losses were 8.18%, 1.67%, 2.85% and 3.58% at producers, wholesalers, retailers and catering institutions/consumer stage, respectively, while the corresponding values in the kocho chain were 5.8%, 15.2%, 24% and 5.8%, respectively. In the bulla chain, 1.4%, 3.1%, 12.6%, 28.8% and 4.5% losses were estimated to occur at producers, wholesalers, retailers, processors and catering institutions/consumer stage, respectively. The loss hotspots identified were cooperatives, farmers, retailers and processors for milk, teff, kocho and bulla, respectively. Poor handling at collection points, the threshing process and poor packaging and processing facilities were among the major problems causing losses. Tobit model analysis identified distance to the nearest market as the most important factor for farmers’ post-harvest losses, while Probit analysis identified attendance in formal education as most determining for value addition decisions in the teff chain. Relationships among the chain actors were mostly based on spot transactions, lacking long-term market orientation and adequate mutuality and trust. However, application of supply chain management (SCM) practices could potentially improve the overall supply chains and reduce food losses.
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| 4. |
- Andersson, Emma
(författare)
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Impact of litter size on sow health and welfare
- 2018
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Genetic improvement of litter size has been the main breeding goal in piglet production during the last decades, resulting in a steady increase in total number of born piglets in each litter both in Sweden and in other European countries. It has been suggested that large litters pose a major welfare problem for sows and piglets. However, there is a lack of recent studies investigating the impact of litter size on the health and welfare of sows. Therefore the objective of this thesis was to investigate the association between litter sizes and sow health and welfare. The two studies included in this thesis were performed as observational studies and investigated by retrospective analysis of available pig production data. The first study investigated the association between litter sizes and sow stayability, and the second study the association between litter size and medical treatment of sows during farrowing and lactation. The final dataset used in the first study included a study population of 38 878 sows in 24 herds and the final dataset in the second study included observations from 1 947 litters from 655 sows. Associations between litter size and sow health and welfare was found. There was an association between litter size and stayability of the sow, as well as association between litter size and medical treatment of the sow. The results from both studies imply that sows with medium sized litters have a better lifetime production than sows with very small or large litters. Piglet producers should therefore pay even more attention to prophylactic management of sows during gestation and lactation. In planning of breeding strategies and annual removal of sows, piglet producers should also aim for keeping sows giving birth to a medium-sized litter, with approximately 12 to 14 piglets born in total in their breeding program, as this seems to improve sows’ stayability and decreasing the risk of unplanned removal which would favour health and welfare of both sow and piglets.
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| 5. |
- Aradom Messmer, Samuel
(författare)
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Animal transport and welfare with special emphasis on transport time and vibration including logistics chain and abattoir operations
- 2012
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- During transport animals are exposed to a number of stressors such as, separation from familiar and mixing with unfamiliar groups, vibration and transport time. Logistics chain of animals comprises collecting from farms, transport, unloading and slaughter chain operations. The current licentiate thesis deals with transport of pigs and cattle from farms to abattoirs including all logistics chain. Two trucks with natural ventilation and air suspension systems were used for field experiments. Stress hormones such as cortisol, glucose, lactate and creatine kinease, ethological parameters, carcass pH value, temperature and relative humidity were measured to study effect of transport on pigs welfare. Vibration levels on chassi, floor and cattle were studied and the influence of speeds, road types and cattle standing orientations on vibration levels were investigated. Field measurements were also conducted to describe the potential effect of operations planning and route optimization on welfare and meat quality. Highest pH24 value was (5.990.29) at 12 h summer transport time. Concentrations of cortisol was inversely proportional (P<0.001) to transport time, lactate and creatine kinase (P<0.002) positively correlated where as glucose level (P<0.01) was highest at 8 h transport time. Lying, sitting and rooting correlated with transport time (P<0.009). On cattle, highest vibration was 2.27±0.33 m s-2 during transport on gravel road at 70 km h-1. Vibrations in horizontal and lateral directions were lower on animals positioned perpendicular to driving direction. Uneven distributions of arrivals affected handling at the delivery gate. Unloading, including waiting and preparation, varied between 7 and 98, with an average of 23.7 minutes. Queues at washing occurred at 29% of deliveries, with waiting of up to 56 minutes. Potential savings for individual routes was up to 23%, consequently reducing negative impact on animal welfare, meat quality and environment. Based on climatic conditions, behaviours, stress hormones, and final carcases pH values, an increase from 4 to 8 h had higher effect than from 8 to 12 h transport time. To reduce vibration levels animal transporters more have to adapt vehicle's speed to road and animal conditions. Time and distance of transport activity can be reduced through effective planning and route optimisation which also improves animals' welfare and environmental impact.
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| 6. |
- Back, Pär-Erik, 1961
(författare)
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On Uncertainty and Data Worth in Decision Analysis for Contaminated Land
- 2003
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Contaminated soil and groundwater is a problem that has received increased attention in the last decade. Decision-making about investigation strategies, protective actions, and remedial actions is based on sparse and uncertain information, primarily data of contaminant concentrations and geological information. Because of limited economical resources, cost-efficient decisions must be made. Risk-based decision analysis is a tool for evaluating the cost-efficiency of different decision alternatives. Identification of cost-efficient site investigations can be performed by applying data worth analysis. In such an analysis, the value of additional sample data is compared to sampling cost and if the data worth is larger than the cost it will be worthwhile to carry out the sampling. Because environmental samples are uncertain, this uncertainty should be considered in the analysis. An approach for estimation of uncertainty in soil sampling is presented. It is based on the sampling theory for particulate materials developed for the mining industry. The sample uncertainty is broken down into eight basic types of uncertainty and variability. An application of the methodology is presented for the problem of soil sampling with a drill auger. The result indicate that the uncertainty in sample data can easily be in the range of 30-40 %. The sampling uncertainty is believed to be much more important that the analytical uncertainty. A methodology for including sample uncertainty in data worth analysis is presented. It is based on a Bayesian approach to data worth. The sampling objective is to estimate the mean concentration at a site. A MathCad computer application for the calculations is supplied. An application of the data worth estimation procedure is presented for a sampling problem at a former Ferro-alloy work in Gullspång, Sweden. A conclusion is that prior estimates of contaminant concentrations may have a significant impact on the result, as well as estimates of failure cost. It is recommended to use different estimates of failure cost to study its influence. Results also indicate that when sample uncertainty is increased, the expected net value of the sampling program will decrease moderately and relatively constant. In situations where contamination has not yet occurred, cost-efficient protective actions need to be identified to combat environmental risks. A methodology for selecting costefficient protective actions for water supplies along railways has been developed. The risk object is railway transport of dangerous goods. Also for this problem, estimation of failure cost is believed to be important for the result. The need for additional development of the methodology is identified. Estimation of uncertainty in soil sampling can be improved and the described theory extended. The methodology for data worth analysis for contaminated land should be extended to take additional sampling objectives into account. contaminated land, data worth, decision analysis, risk, sampling, uncertainty
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| 7. |
- Beier, Ulrika
(författare)
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Habitat selection and indirect interactions in fish communities : mechanisms to explain spatial distribution of perch, roach, and vendace
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- To increase the understanding of freshwater lake ecosystems, I have studied the habitat selection of perch (Perca fluviatilis L.), roach (Rutilus rutilus (L.)), and vendace (Coregonus albula (L.)). These fish species use the pelagic and the littoral-benthic habitats in lakes to different extents. Perch and roach are omnivorous, and perch become piscivorous at larger sizes. Vendace is a pelagic species specialized in eating zooplankton. Vendace was expected to affect biotic interactions and habitat use of roach and perch, both directly and indirectly. I used monitoring data to examine how species distribution patterns, as well as population structures, depended on species composition. In a predation experiment, I studied the relative predation sensitivity as well as evasive behaviours of roach and vendace, with piscivorous perch used as predators. In foraging experiments in aquaria, I studied foraging efficiencies and swimming performances of roach and vendace eating zooplankton in different temperature and light treatments. I then applied metabolic models for roach and vendace, respectively, to compare their net energy gain in different abiotic conditions. Roach used the pelagic habitat less, and the biomass of roach was lower in lakes with vendace. Results did not support the prediction that perch populations would benefit from the presence of vendace. However, results indicated that a release of competition for small perch may be mediated by vendace, through changed habitat use of roach, increasing the possibilities for predation. Roach and vendace were similar in their sensitivity to predation, indicating that energy gain can explain their habitat use. Foraging efficiencies did not explain the habitat use of roach and vendace in the field. However, the net energy gain in different abiotic conditions, could explain observed patterns of their habitat use in lakes. This thesis shows how the trade-off between mortality and net energy gain is manifested in habitat use. Including habitat selection in ecological studies may increase our understanding of biotic interactions. Metabolic costs as well as foraging abilities in different abiotic conditions are important for explaining the habitat use of species. Such knowledge can make it possible to forecast how interacting fish species may be affected by environmental change.
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| 8. |
- Bell, David
(författare)
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Forest restoration guided by an umbrella species : will measures to protect the white-backed woodpecker benefit saproxylic beetles?
- 2015
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Management shortcuts in conservation biology, like the umbrella species concept, have been debated worldwide. Umbrella species have been used to identify and delineate protective areas, but habitat requirements of umbrella species can also provide tangible targets in ecological restoration. In Sweden, forest habitats have been restored for the white-backed woodpecker (WBW, Dendrocopos leucotos) under the assumption that it will benefit other habitat-associated (background) species. In this thesis, the umbrella species concept was evaluated based on the response of wood-inhabiting (saproxylic) beetles to forest restoration for the WBW. The WBW is a top-predator in saproxylic food webs associated with broadleaved trees, but it is also critically endangered in Sweden because of commercial forestry practices that disadvantage broadleaved trees and reduce dead wood availability. Spruce trees (Norway spruce, Picea abies) were selectively harvested during forest restoration to make way for broadleaved trees like birch (Betula spp.) and European aspen (Populus tremula). Some broadleaved trees were also killed to create high-stumps (snags) and downed logs. Commercially managed forests were compared with restored forests; either directly in comparative studies, or before and after forest restoration. Two types of flight-intercept traps were used to catch saproxylic beetles: IBL2-traps and trunk-window traps. Results presented in this thesis show that habitat requirements of an umbrella species can be used to guide forest restoration. There were many beneficiary species at the stand-level. Commercially managed and restored forests were inhabited by different communities of saproxylic beetles, and species positively associated with broadleaved trees and sun-exposed substrates were particularly responsive. This was reflected by an increased species richness and abundance. Several near-threatened and vulnerable species were also attracted to substrates created for the WBW. This shows that efforts to bring back the WBW can benefit other resource-limited groups of conservation concern. Saproxylic beetles might even facilitate restoration efforts since many important prey species for the WBW were attracted to restored sites. Umbrella species, like the WBW, will require landscape-level efforts to recover. This is a strength of the umbrella species concept, but also a weakness since landscape-level efforts are time consuming. The WBW is still struggling in Sweden, and failed attempts to re-establish viable populations might undermine conservation incentives. Early signs of progress, however, are sometimes provided by less demanding species, like many saproxylic beetles in this thesis. Background species can also provide much needed examples of restoration success at the stand-level.
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| 9. |
- Bennet, Patrik, 1995
(författare)
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Characteristics of Vertical Forest Backscatter Profiles Measured using Radar Tomography
- 2023
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Forests are an integral part of the Earth’s climate system, having shaped the conditions of life throughout millions of years, but the coverage and conditions of forests are under rapid change. To monitor this change and predict the impact on climate, yearly global mapping of forest Above-Ground Biomass (AGB) is needed. Synthetic Aperture Radar (SAR) is a well-suited technique for this purpose, able to sense through dense canopies with high spatial resolution. Tomographic SAR (TomoSAR) resolves the vertical distribution of backscatter by constructing 3D tomograms of forested areas. Here, results obtained in the TomoSense project are presented, where sensitivity of P- and L-band TomoSAR to AGB of a temperate forest is analysed. For the first time, differences between the AGB dependence of spruce and beech vertical backscatter profiles are identified. Moreover, unique observations of ground slope influence on TomoSAR AGB retrieval are presented. The effect for P-band is significant, but not for L-band. For spruce, AGB was estimated for P-/L-band (ground slopes below 10◦), with R2 = 0.86/0.75 and RMSE = 15.6/12.5%. Without separating forest types, R2 = 0.77/0.54 and RMSE = 11.4/12.0%. Finally, unique L-band radar tomography observations using the BorealScat tower-based radar are presented. Time series of the vertical backscatter profile of a boreal forest during the summer of 2018 is analysed. Weekly diurnal cycles up to 1.3 dB are observed, showing clear differences depending on both canopy height layer and polarization. These differences are new results which are likely related to tree transpiration phenomena but needs further study.
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| 10. |
- Bergkvist, Johan
(författare)
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Landskapsarkitektur i järnvägslandskap : platsernas förändring i historiskt perspektiv
- 2013
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Järnvägens organisation för skötsel av den yttre miljön avvecklades redan i början av 1970-talet. Järnvägsparker och andra planteringar togs bort eller förenklades för att minska skötselbehovet. Banverket bildades1988 med uppgift att förvalta och utveckla statens spåranläggningar. Det nya verket övertog då också en stor mängd tidigare välvårdad park- och trädgårdskultur, med redan då tämligen eftersatt skötsel. Den svenska järnvägssektorn har därefter, liksom många andra europeiska järnvägsorganisationer, genomfört omfattande förändringar för att göra verksamheten effektivare och mer ekonomiskt bärkraftig. Detta har skett genom teknisk utveckling, fortsatta rationaliseringar och avregleringar. Samtidigt som allt detta skett har järnvägens fysiska miljöer, med sin tidigare så förebildliga arkitektur och trädgårdskonst, hamnat i skymundan. Avhandlingen huvudfrågor är hur den pågående fysiska omvandlingen av järnvägsmiljöerna kan beskrivas och kategoriseras och hur värden i arkitektur och trädgårdskonst kan tillvaratas. En stor mängd av järnvägens stationer och andra järnvägsmiljöer har besökts och dokumenterats under denna tid. Ett snävare urval har sedan legat till grund för en flerfallstudie där de fysiska förändringsprocesserna studerats på ett systematiskt sätt. Förändringen av de undersökta miljöerna följer med små variationer samma mönster överallt. De karakteriseras av förskjutningar i olika riktningar, även vertikala när spårens höjdläge förändras. Tillkommande eller utbytta funktioner och strukturer överlagrar ofta de gamla. Samtliga studerade järnvägsmiljöer har också reducerats i förhållande till sin ursprungliga utbredning. Spår och fragment från olika generationers anläggningar är ofta synliga i den omgivande miljön; igenväxande och ibland i rent förfall. Olika teoretiska perspektiv har använts för att diskutera hur järnvägsmiljöernas förändring kan beskrivas och tolkas. Slutligen diskuteras vilket värde järnvägens kulturarv har i den förnyelse- och omvandlingsprocess som pågår och om det är möjligt att se den historiska järnvägens materiella och immateriella kulturarv inte bara som en kostnad och ett problem utan också som resurs i ett hållbarhetsperspektiv. Avhandlingen vill fästa uppmärksamheten på dessa materiella och immateriella värden och de argument som finns för att integrera och återbruka dem i den pågående fysiska omvandlingen av järnvägssystemet.
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