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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
471

Protecting dogs against attacks by wolves (Canis lupus), with comparison to African wild dogs (Lycaon pictus) and dholes (Cuon alpinus)

Fedderwitz, Frauke January 2010 (has links)
In this thesis five different protection harnesses for hunting dogs against canidae attacks were assessed. Hunting dogs can be attacked and severely injured or killed by wolves (Canis lupus) when released during hunting. So far there is no effective protection method. Similar problems are reported with African wild dogs (Lycaon pictus) and dholes (Cuon alpinus) with other domestic animals. In this study the experimental harnesses were presented on a dummy to lure the animals to attack them. The harnesses with physical (screws or spikes on the back) and ultrasound (immediate bite controlled and 19 second continuous ultrasound) deterrents were only assessed during wolf attacks, whereas the harness with electric shocks was also tested on the other two species. Neither physical nor ultrasound deterrents showed a large enough aversive response in the wolves. Electric shocks, given to the animals when biting the dummy, triggered an immediate release of the dummy in all three species. Long term effects differed between species and individuals. The exposed wolf did not touch the dummy again after a second exposure, whereas all except one African wild dog bit the dummy again in consecutive trials. Some individuals returned to bite a second time even in the same trial. An assessment of the long term effect on dholes was not possible, as the individuals were undistinguishable. Based on the data obtained in this study a harness with electric deterrent seems the most promising.
472

A study of use patterns, user satisfaction and willingness to pay for off-leash dog parks: post-occupancy evaluations of four dog parks in Texas and Florida

Lee, Hyung-Sook 15 May 2009 (has links)
The growing importance of dogs in people’s lives and in high-density urban environments has increased demand for a place where people and their dogs can interact and exercise together. The recent increase in the number of dog parks across the country is evidence of these demands of dog owners and their companions. However, due to the absence of empirical study on dog parks and their attribute of non-market values, the benefits of dog parks are often underestimated and considered less in the decision making process regarding resource allocation. A post-occupancy evaluation at four dog parks was conducted to investigate use patterns of dog parks and user activities, to identify user preferences and the environmental factors influencing activities, to provide insights and guidelines in developing effective dog parks, and to estimate users’ willingness to pay for dog parks using contingent valuation method. A multiple-method approach was used to collect data including site observations and analysis, a questionnaire and behavioral mapping. The results indicated that dog parks received considerable use, served a variety of demographic groups and supported their exercise and social activities. Dog-park users were generally satisfied with dog parks but they expressed various preferences and needs. It is evident that dog parks are not only a place for dogs to exercise but a place for people to exercise, socialize, relax and enjoy greenery just like other parks. Proximity of dog parks was found to be a critical factor in encouraging frequent dog park use and satisfying users’ needs. Over eighty percent of survey respondents expressed that they were willing to pay an annual fee for dog parks, indicating the importance of visiting dog parks as outdoor recreation. Conservative estimate of average willingness to pay was $56.17/ household/ year. Satisfaction with maintenance and facilities, income, education and family size were found to be significantly associated with willingness to pay. These results could assist local governments and park planners in estimating aggregate monetary value of the dog parks and cost-benefit analysis to justify the development and maintenance of dog parks. Design guidelines and recommendations were generated based on the empirical findings for future design of dog parks.
473

Investigations into Hyperlipidemia and its Possible Associations with Pancreatitis in Dogs

Xenoulis, Panagiotis 2011 May 1900 (has links)
The relationship between hyperlipidemia and pancreatitis remains obscure in dogs. The aim of the present study was to investigate any possible association between hyperlipidemia and pancreatitis in dogs. In the first part of the study, Miniature Schnauzers with hypertriglyceridemia were found to have significantly higher serum cPLI concentrations than Miniature Schnauzers with normal serum triglyceride concentrations (P=0.0001). Also, Miniature Schnauzers with severe hypertriglyceridemia (>862 mg/dL) had 4.5 times higher odds (P=0.0343) for having a serum cPLI concentration consistent with pancreatitis. In the second part of the study, 17 Miniature Schnauzers prospectively enrolled with a history of pancreatitis were significantly more likely to have hypertriglyceridemia (71 percent) after resolution of pancreatitis than 34 age-matched Miniature Schnauzers without a history of pancreatitis (33 percent; odds ratio=5.02; P=0.0163). For the third part of the study, assessment of the feasibility and usefulness of a novel density gradient ultracentrifugation method using NaBiEDTA for lipoprotein profiling in dogs was attempted. Density gradient ultracentrifugation using NaBiEDTA was found to be useful for the study of lipoprotein profiles in dogs. Significant differences were detected in the lipoprotein profiles (mainly involving TRL and specific LDL fractions) among healthy Miniature Schnauzers, dogs of various other breeds, and hypertriglyceridemic Miniature Schnauzers. In the fourth part of the study, the effect of a commercially available low-fat diet on serum lipid and pancreas-specific lipase (Spec cPL) concentrations and lipoprotein profiles in Miniature Schnauzers with primary hypertriglyceridemia was evaluated. The study diet was found to be effective in significantly reducing serum triglyceride and cholesterol concentrations and changing the lipoprotein profiles of the dogs studied within 2 months. However, there was no significant effect of the study diet on serum Spec cPL concentrations. In the last part of the study, serum triglyceride and cholesterol concentrations and lipoprotein profiles were compared between dogs with naturally occurring pancreatitis and healthy dogs. The majority of dogs with naturally occurring pancreatitis had normal serum triglyceride and cholesterol concentrations. Important differences were identified in lipoprotein profiles between dogs with pancreatitis (higher LDL2, LDL3, and LDL4 fractions and lower TRL, HDL2a, and HDL3c fractions) and healthy control dogs.
474

Analysis of domestic dog mitochondrial DNA sequence variation for forensic investigations

Angleby, Helen January 2005 (has links)
<p>The first method for DNA analysis in forensics was presented in 1985. Since then, the introduction of the polymerase chain reaction (PCR) has rendered possible the analysis of small amounts of DNA and automated sequencing and fragment analysis techniques have facilitated the analyses. In most cases short tandemly repeated regions (STRs) of nuclear DNA are analysed in forensic investigations, but all samples cannot be successfully analysed using this method. For samples containing minute amounts of DNA or degraded DNA, such as shed hairs, analysis of mitochondrial DNA (mtDNA) is generally more successful due to the presence of thousands of copies of mtDNA molecules per cell.</p><p>In Sweden, ~40 % of all households have cats or dogs. With ~9 million humans shedding ~100 scalp hairs per day, and ~1.6 million cats and ~1 million dogs shedding hairs it is not surprising that shed hairs are one of the most common biological evidence found at crime scenes. However, the match probability for domestic dog mtDNA analysis has only been investigated in a few minor studies. Furthermore, although breed –sequence correlations of the noncoding mtDNA control region (CR) have been analysed in a few studies, showing limited correlations, no largescale studies have been performed previously. Thus, there have not been any comprehensive studies of forensic informativity of dog mtDNA. In the two papers presented in this thesis we have tried to lay a foundation for forensic use of analysis of domestic dog mtDNA. In the first paper, CR sequences were analysed and the exclusion capacity was investigated for a number of different populations. This is also the first comprehensive study of the correlation between mtDNA CR type and breed, type, and geographic origin of domestic dogs. Since the exclusion capacity for analysis of domestic dog CR sequences is relatively low, it was investigated in the second paper to what extent the discrimination power is improved by analysis of coding sequence. The exclusion capacity improved considerably when 3,000 base pairs of coding sequences where analysed in addition to CR sequences. This study will hopefully work as a basis for future development of analysis of dog mtDNA for forensic purposes.</p>
475

Labrador and German shepherd breed differences in dog-human communication

Grozelier, Anna January 2015 (has links)
As our long-term companions, dogs’ communication with us is perhaps the most developed of all human- animal ones. This study was aimed to investigate breed differences of German Shepherds and Labradors in dog-human communication. This was obtained through two tests: a problem-solving task and a pointing test. These two tests target both directions of communication: how much dogs understand and respond to the pointing and how they communicate with humans when facing a problem. Additionally, hair cortisol was measured in the dogs and dog owners filled a behavioural questionnaire (C-BARQ). The main breed difference I found was that Labradors performed better in both tests. I also found that the latency of the dogs’ choices in the pointing test correlated with many factors, e.g. they chose quicker when: choosing correctly, when they had many physical contacts with the experimenter in the problem-solving task, when they were more intense, energetic dogs, when they had higher hair cortisol levels and when they had a confident body posture. This indicates that the latency of choice could depend on the confidence of the dog and on the trust in the experimenter as well as on energy level and focus ability. Overall, this study revealed a limited amount of breed differences, compared to a parallel study on Labrador types (hunting and show dogs), showing that intra-breed differences can be more important than inter-breed ones on a behavioural level.
476

Structural framework and seismic geomorphology of the Cretaceous beneath the Mad Dog Area, deep to ultradeep waters Gulf of Mexico

Markez, Damian 01 November 2013 (has links)
Recent drilling of deep stratigraphy in subsalt offshore Gulf of Mexico has revealed the presence of thick, amalgamated, Cretaceous siliciclastic reservoirs with the potential to become valid exploration targets. Similar to the Lower Tertiary deepwater play, the significant down-dip distance (> 400 km) from the source deltaics, the data gap across the modern structurally complex salt-tectonics-dominated slope and the difficulties of imaging subsalt stratigraphy pose challenges for the construction of meaningful deepwater system models to aid in exploration and appraisal efforts. A 3D seismic dataset in the Mad Dog field at the basinward end of the modern allochthonous salt canopy and outboard of the Sigsbee Escarpment offers the opportunity to study the nature of the deep stratigraphy at central positions in the basin. The nature of the Cretaceous sedimentary system has been investigated through detailed structural and seismic geomorphologic mapping. An early syndepositional contractional event has been identified and temporally associated with Mesozoic emplacement of a deep salt sheet. These events are masked by the major Neogene-age phase of fold amplification that dominates the present-day subsalt structural framework. Ponded-basin deepwater sedimentation processes control early phases of deposition in the Cretaceous Mad Dog area and sediment-gravity flows are deposited as complexes of low sinuosity amalgamated channelized deposits in roughly-confined sediment pathways. Ponded fills show internal lateral accretion architectures that grow sigmoid in nature as the migrating systems interact with the approaching minibasin margins making evident the structural control on sediment architecture. Later phases of deposition are characterized by slightly sinuous feeder channels with multiple lobe development at their terminus. Variable directions of sediment source pathways indicate a linear-sourced slope apron depositional model for these systems. In addition to the more structured morphologic elements, there were also pervasive mass-transport processes active, presumably triggered by Mesozoic halokinesis. Data in sparse deep wells in the GoM that penetrate the Cretaceous suggest that the Late Cretaceous deepwater depositional system was composed of coarse-grained high density gravity flows. The geometries seen in seismic beneath the Mad Dog area support the existence of such a basinwardly extensive deepwater fan systems developed during the Cretaceous, and the low sinuosity channel geometries and small length:width ratio and amalgamated nature of fan lobes suggest that these systems may have indeed been high-density in nature. / text
477

En vårdande instinkt : En litteraturöversikt om hundens hälsofrämjande effekter för patienten / A caring instinct : A literature review about the dog’s health benefits for the patient

Sahlgren, Emilia, Lawrence, Melanie January 2015 (has links)
Bakgrund: Hunden har länge funnits vid människans sida och varit en värdefull följeslagare. Aktuell forskning rymmer lovande bevis för hundens positiva effekter på människans hälsa. Djurassisterade interventioner med hundar är trots denna forskning i dagsläget en relativt oanvänd resurs i omvårdnadssammanhang. Syfte: Belysa hundens hälsofrämjande effekter för patienten. Metod: En allmän litteraturöversikt baserad på nio kvantitativa artiklar och en kvalitativ artikel. Resultat: Fyra huvudkategorier som speglar hundens hälsofrämjande effekter identifierades. Dessa var emotionella effekter, fysiska effekter, sociala och kognitiva effekter samt psykiska effekter. Slutsats: Det har identifierats att hunden kan påverka varierande hälsoaspekter hos människan i en positiv riktning. Klinisk betydelse: Genom att ha kunskap om vilka hälsofrämjande effekter hunden potentiellt kan medföra för patienten kan vårdpersonal få ännu ett verktyg för att närma sig personcentrerad omvårdnad. / Background: Dogs have for a long time been living by the human side and has been valued as meaningful companions. Current research contains promising evidence for the positive health benefits the dog may have on humans. Despite this research animal-assisted interventions containing dogs are a relatively unused resource in nursing context. Aim: To illuminate the health benefits that dogs in healthcare can have for the patient. Method: A general literature review based on nine quantitative articles and one qualitative article. Results: Four main categories that reflect health benefits dogs can contribute to were identified. These were: emotional effects, physical effects, social and cognitive effects and psychological effects. Conclusion: It was identified that dogs may affect several aspects of human health in a positive direction. Clinical relevance: By having knowledge about which health benefits dogs potentially can have for the patient, health professionals have yet another tool to approach person-centered care.
478

Quantitative seismic geomorphology of a confined channel complex, southern Atwater fold belt, Gulf of Mexico, U.S.A.

Morgan, Jessica Leanne 02 November 2011 (has links)
The structures along the Atwater Fold belt form important deep-water hydrocarbon traps in the northern Gulf of Mexico. The purpose of this study is to map and quantify the morphology, sedimentology and architecture of Plio-Pleistocene basin floor fan systems outboard of the Poseidon Minibasin, located along the Atwater deep-water fold belt (mid-Miocene to Pliocene), and apply that information to determine the temporal and spatial nature of the fill and its implications as a reservoir analog. The data set includes ~2200 km sq. of 3D seismic data, along with information from several wells. Wireline logs show the Tertiary age deposits outboard of the Sigsbee Escarpment to be several hundred feet thick, sharp-based, dominantly coarse-grained (sandy) but fining up cycles composed of sandy basin floor fans, mass transport complexes and leveed channels developed in a confined setting within deep-water “valleys.” The largest valley formed in five main stages: initiating from narrow channel incision, widening through lateral incision and sidewall slumping, straightening, and finally flooding and infilling. The valley system is ~20,000 feet across and ~ 1,400 feet deep, with what look like well-developed levees ranging from 700 to 1300 feet at their thickest point extending ~19000 feet away from the channel. This system is underlain by a ~700 foot thick mass transport complex and overlain by younger, low sinuosity leveed channel systems. Both of these systems appear to have been sourced by large submarine drainages, originating from a shelf edge sediment source system to feed the rugose slope with deep-water channel pathways uninhibited by salt wall inflation at the time of valley deposition. Major phases of salt thrusting along the southern edge of the Atwater were contemporaneous with the formation of these large, through-going valley system, which appear to be associated with the period of sheet thickening and development of monoclinal basinward dip related to rafted mini-basin docking. Well log signatures show evidence for armored clay drapes along the valley margins as well as a flattening of lateral accretion packages toward the distal end of the system. The flattening of these packages seems to signal proximity to the fan terminus, which would serve as an important indicator of spatial extent of plays in deep-water. / text
479

A Walk in the Park: Zoonotic Risks Associated with Dogs that Frequent Dog Parks in Southern Ontario

Procter, Theresa D. 06 September 2012 (has links)
A cross-sectional study investigated the shedding of zoonotic organisms (Campylobacter, Giardia, and Salmonella) and antimicrobial resistant generic E. coli in dogs that visited dog parks in southern Ontario. Logistic regression models were constructed to identify risk factors. Factors for the shedding of Campylobacter spp. included consumption of a commercial dry diet, exposure to compost, and age. Factors for the shedding of C. upsaliensis included outdoor water access and age. A risk factor for ampicillin resistance was attending a dog day care. For resistance to at least one antimicrobial, factors included attending a dog day care, breed size, consumption of a commercial dry diet and consumption of a homemade cooked diet. For multiclass resistance, exposure to compost, breed size, and consumption of a commercial dry diet were identified. Park was not significant in any model. Dogs that visit dog parks shed organisms that may pose a human health risk. / Canadian Institutes of Health Research (CIHR) Institute of Population and Public Health/ Public Health Agency of Canada Applied Public Health Research Chair awarded to J. M. Sargeant; Public Health Agency of Canada; Ontario Veterinary College Pet Trust Fund; and a grant to D. L. Pearl from the Canada Foundation for Innovation and the Ontario Research Fund.
480

Comparison of Hemilaminectomy and Mini-hemilaminectomy in Dogs with Thoracolumbar Intervertebral Disc Extrusion Using Computed Tomography and Magnetic Resonance Imaging: An Anatomical and Radiological Study

Huska, Jonathan 15 January 2013 (has links)
This thesis is an investigation of the access provided to the vertebral canal in dogs by the hemilaminectomy and mini-hemilaminectomy surgical techniques using computed tomography (CT), and the completeness of evacuating extruded material in dogs with intervertebral disc (IVD) extrusion using magnetic resonance imaging (MRI). Hemilaminectomy and mini-hemilaminectomy were performed on opposite sides of the spine at T11-T12, T13-L1, and L2-L3 in 10 cadavers. Measurements of the vertebral canal height, defect height, and any dorsal and ventral remnants of the vertebral arch were obtained by CT. A covariate analysis was used to compare measurements with the surgical technique, surgical site, and side of the vertebral column. Defect height was greater with hemilaminectomy due to a smaller dorsal lamina remnant. There was no statistical difference in the height of the ventral remnant, or with surgical site. Nineteen prospectively recruited dogs with suspected IVD extrusion were randomly assigned to hemilaminectomy (10 dogs) or mini-hemilaminectomy (9 dogs) groups. Intervertebral disc extrusion was identified pre-operatively with MRI and later confirmed surgically, and immediate post-operative MRI was performed at the surgical site. The volume of extruded IVD material pre- and post-operative was calculated from transverse T2 images. Although residual IVD material was present in post-operative images from all dogs in the hemilaminectomy group and only 4 in the mini-hemilaminectomy group, there was no statistically significant difference between the proportionate volumes of material removed by either technique. The median residual volume with hemilaminectomy was 13.6% (confidence interval: 7.8 – 23.6%), and with mini-hemilaminectomy was 7.7% (4.3 – 13.8%). The results of this study confirm that the difference in the defect height between techniques is related to the removal of the articular processes creating a larger defect along the dorsal vertebral canal, while no difference in access to the ventral canal was observed. No effect of vertebral site was detected suggesting neither procedure provides an advantage over the other due to location of the lesion along the thoracolumbar spine. Residual extruded IVD material occurs with both techniques; while no statistical difference was noted, a larger population should be examined. / Ontario Veterinary College Pet Trust

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