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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.
51

Genetic analysis of canine hip dysplasia

Tsai, Kate Leanne 25 April 2007 (has links)
The morphologic variability seen in the domestic dog, Canis lupus familiaris, is unique among mammals. Selective pressures imposed by humans have divided dogs into almost 400 separate breeds. Selection has also led to the development of approximately 450 hereditary diseases, many of which are limited to specific breeds. Over half of these diseases present with similar clinical characteristics to those of many human hereditary diseases, making the dog an ideal model for study of the genetic bases of such diseases. Many diseases do not have candidate genes or have too many candidates to characterize. This is exacerbated in complex diseases that are caused by several genes. Whole-genome scans can provide insight into diseases by identifying marker(s) that co-segregate with a disease phenotype. The Minimal Screening Set - 2 (MSS-2) is the most recent set of microsatellites suitable for whole-genome screens. The first objective of this work was to streamline genomic screens in order to efficiently analyze large numbers of animals. To this end, chromosome-specific microsatellite panels were developed for the MSS-2. Canine hip dysplasia (CHD) is the most common orthopedic disease of the dog. CHD primarily affects medium and large breed dogs, but is found in almost every breed. The major objective of this work was to use linkage analysis to identify chromosomal regions that contain genes that are involved in CHD. Two populations were screened using the MSS-2. The first was a small family of Boykin Spaniels, though no markers were statistically significant in a whole-genome screen. An outcrossed pedigree of Greyhound/Labrador Retrievers was created for quantitative trait loci (QTL) mapping of CHD. The informativeness of markers in the F2 and backcrossed generations were calculated to show the utility of using such a population. Other factors that affect the power of this pedigree to identify QTL were also highlighted. Chromosomes that were identified in a previous screen as harboring putative QTLs were examined using the chromosome-specific panels to further define and confirm the regions of interest. Although no markers reached statistical significance, several areas of interest were identified.
52

Assessing the repeatability and validity of a questionnaire on pain and lameness in the canine

Hudson, Jonathan Thomas 30 September 2004 (has links)
The measurement of pain has had a growing importance in animals for both privately owned animals and those animals involved in clinical research. Lameness is considered to be 1 aspect of the pain experience. The ability of a veterinarian to assess lameness during a routine orthopedic examination can be difficult given the short amount of time in which the clinician can observe the animal, and the fact that the animal is in a stressful environment. Thus, the input of the owner concerning the animal's well-being over an extended time period may be extremely useful to the clinician in assessing the degree of lameness of the animal. It was the purpose of this study to establish an instrument that was both repeatable and valid in assessing the degree of lameness. The instrument used was a questionnaire containing 39 questions in a visual analog scale format. A force platform was used as the gold-standard for detecting mechanical lameness. Peak vertical, cranial-caudal, and their associated impulses were forces used to determine lameness, along with maximum slope in some cases. A test-retest measure of repeatability was conducted on a subset of 19 dogs that were confirmed to have less than a 10% change in vertical peak force. Nineteen of the 39 questions were found to be repeatable based on a Spearman rank correlation. These 19 questions were then used as predictor variables in several multiple regression models which predicted force plate measurements. The result was 3 different models each containing 7 independent variables that were thought to be valid representations of the forces measured (vertical peak, vertical impulse, and propulsion peak forces). Each reduced model was found to fit the data as well as the full model containing all 19 of the repeatable questions. The composite of 11 questions from the 3 different models was used to calculate a total score. This total score was found to be significantly correlated with force plate measurements. These 11 questions should be useful to a clinician in detecting the degree of lameness in the dog.
53

Purification and Characterization of a Recombinant Glycoprotein, Canine Thyroid Stimulating Hormone, as a Prelude to the Development of the Reproductive Glycoproteins

Delovio, Malcolm Leihulu 2012 August 1900 (has links)
A baculovirus (Spodoptera frugiperda) system was designed to express recombinant canine thyroid stimulating hormone (rcTSH). The efficacy of rcTSH was measured against pituitary derived bovine thyroid stimulating hormone (bTSH) through a series of in vitro and in vivo experiments. Initial purification of rcTSH was performed in order to characterize the hormone for further analyses. Ion exchange columns and tangential flow membranes were chosen based upon the traits of the rcTSH molecule. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gels visualized by Coomassie blue, silver stain, and western blot demonstrated the effectiveness of the purification process. Primary cell, static tissue, and perifusion tissue cultures were employed to investigate in vitro thyroid cell/tissue response to rcTSH and bTSH. Canine thyroid cells were liberated from tissue samples, cultured, then exposed to TSH treatments in which media was subsequently harvested and measured for cyclic adenosine monophosphate (cAMP), a second messenger in the TSH downstream signaling cascade. The cAMP concentrations measured were sporadic and not consistent with expected concentrations for treatments or controls. For the static tissue culture, slices of bovine thyroid tissue were incubated and exposed to a series of media-only wash steps as well as treatment steps using varying concentrations of rcTSH. Unfortunately, the experiment was compromised resulting in the slow release of thyroxine (T4) for all samples due to tissue death. Perifusion experiments conducted on bovine thyroid tissue compared the release of T4 due to bTSH and rcTSH stimulation in a dynamic system. Unable to perform statistical analysis due to small sample sizes, graphical representation demonstrated stimulatory effects by bTSH and rcTSH when compared to control. Biological assays were used to compare the in vivo efficacy of rcTSH to bTSH which included 3 species (goldfish, rat, and canine). Results from mammalian experiments when subjected to analysis of variance (ANOVA) resulted in the rejection of the null hypothesis of equal means (P<0.05) between control, bTSH, and rcTSH treatments. Further analysis by Tukey's W procedure demonstrated the stimulatory actions of rcTSH and bTSH to be similar (P>0.05) to each other while greater (P<0.05) than control at the 4 and 6 hour post injection time.
54

A study of canine lymphoid neoplasia

Quinnell, M. A. Unknown Date (has links)
No description available.
55

The cytology of the canine oral papilloma

Cheville, Norman F., January 1964 (has links)
Thesis (Ph. D.)--University of Wisconsin, 1964. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
56

An exploratory study of dog owners’ experiences in nature

Kennedy, Katelyn 25 May 2018 (has links)
The purpose of this phenomenological study was to explore the experiences of individuals who spend time in nature with their dogs. The study was guided by three key research questions: what is the essence of the experience; how does time in nature with a dog differ from time in nature without a dog; and what are the outcomes of spending time in nature with a dog? Eight participants who spent at least six hours a week in nature with their dog were interviewed. Transcripts were analyzed and coded. Three overall themes (heightened experience, negotiating constraints, and outcomes) emerged, which informed the three research questions. This study connected two related research areas, adding to existing literature on dog ownership and nature experiences. / Graduate
57

Improving rabies control in free-roaming dogs

Morters, Michelle January 2014 (has links)
Canine-mediated rabies is a serious zoonosis responsible for at least 55,000 human deaths every year, primarily in less developed communities in Asia and Africa where domestic dogs are free-roaming. The disease can be effectively controlled through vaccinating at least 45% of the dogs in a population; however the impact of vaccinations on disease incidence may be affected by dynamic demographic and immunological processes. Specifically, the contribution of these processes, and their regulatory factors, to vaccination coverage and rabies transmission has not been comprehensively estimated. To improve rabies control, through field interventions and epidemiological modelling, more information regarding the effect of these processes, and their regulatory factors, on population and disease dynamics and vaccinal responses was needed. This required a multifaceted approach, using techniques from the fields of population ecology, vaccine-immunology, social science and epidemiological modelling. Demographic data were collected from four populations of free-roaming domestic dogs, two in South Africa and two in Indonesia where rabies is endemic. Longitudinal, individual-level data were obtained by direct observation and surveys, and community-level data by participatory methods. Longitudinal, serological data were collected from three cohorts within the populations. Epidemiological models were based on epidemic theory and empirical data from this current study and previous studies. A wide array of data were generated relevant to planning rabies control programmes, however of particular importance was evidence regarding positive and negative the impacts of human factors on population and disease dynamics. Nearly all of the dogs were owned, despite being free-roaming, and were accessible for vaccination through their owners; and population size was regulated through human demand for dogs and a substantial fraction of dogs was acquired from outside the communities. These translocated dogs may contribute to the spread of rabies, necessitating widespread and sustained vaccination programmes. Considerable differences in the handleability of dogs between locations and, thus ease of vaccine delivery, may also be attributable to differences in human-dog interactions. Finally, a critical review of the literature, and evaluation of epidemiological models, suggests that human interference in the transmission processes may reduce the incidence of rabies and vaccination threshold. This study has provided specific evidence that human behaviours are likely to be critically important in relation to the transmission and control of canine-mediated rabies ? and is the first to properly identify this. Further detailed studies are required to explore these behaviours and how they vary culturally and geographically. In addition, the results highlight the critical role that demographic processes more generally, as well as immunological decay, play in influencing the long term success of rabies vaccination programmes. Overall, this research has provided valuable support for planning rabies control programmes and for parameterisation of epidemiological models of infectious diseases, including rabies.
58

Valley Fever Canine Incidence Study

Shubitz, Lisa, Butkiewicz, Christine, Dial, Sharon M 12 September 2016 (has links)
Four to six month old healthy puppies were enrolled in a longitudinal study of their serostatus against the Coccidioides spp. Dog were tested every six months for one year. At the request of investigators, some dogs continued to be tested every six months for two years. Dogs that became ill with clinical signs consistent with coccidioidomycosis received additional testing. Owners were asked to complete a questionnaire regarding exposure risk factors at each routine testing visit.
59

Valley Fever Canine Prevalence Study

Shubitz, Lisa, Butkiewicz, Christine, Dial, Sharon M 12 September 2016 (has links)
381 dogs between 4 and 18 months of age were tested for the presence of antibodies to Coccidioides one time. Dogs were reported as either healthy or sick by the referring veterinarian. Owners were asked to complete a questionnaire regarding their dog's risk factors associated with exposure to Coccidioides at the time of sample collection.
60

A comparative computed tomography study of canine laparoscopic abdominal anatomy pre- and post-insufflation

Elliott, Ross Christopher 18 May 2012 (has links)
Laparoscopy has been shown in human medicine to have a rapid recovery time and less morbidity when compared to open abdominal surgery. It involves the insufflation of carbon dioxide into the peritoneal cavity. This creates a space for the surgeon to work in and manipulate the organs. In the normal abdominal cavity the peritoneal cavity is a potential space obliterated by the serosal contact between all the organs. The insufflation of carbon dioxide turns this potential space into a working space. This allows the introduction of an endoscope, usually through a single port, and then various instruments usually through another port into the peritoneal cavity. Multiple veterinary studies have shown the advantages of laparoscopy to decrease the morbidity of animals post surgery. The visualisation of the organs tends to be enhanced by the increased lighting and magnification provided by the laparoscopic equipment. There are intricate attachments and associations between various abdominal organs that are responsible for maintaining organ position and orientation in the peritoneal cavity. Computed tomography (CT) has been proven in human medicine to show excellent abdominal anatomical resolution. It is the modality of choice to detect free abdominal gas. Logically, if there is a massive insufflation of gas, it would be expected that this will enhance the ability of CT to provide real anatomical likeness to the laparoscopic image. The animals were all subjected to multiple CT scans and the scans were found to be rapid and noninvasive. There was a concern over the amount of radiation that each animal received and this was pre-empted by using a CARE 4D dose. The CT machine detected the thickness of the part of the animal being scanned and only provided the needed kV and mAs to penetrate and create an image. This was a paediatric human modality. Six beagle dogs were used and all assessed prior to the study to be clinically healthy. An abdominal ultrasound was performed to assess that they had normal abdominal anatomy. All animals had eight scans performed, four pre-insufflation (PrI) and four post-insufflation (PoI). The animals were placed in a ventro-dorsal routine (VDR), a ventro-dorsal Trendelenburg (VDT), a left lateral (LL) and a right lateral (RL) position. The scans were performed using a helical dual slice sliding gantry CT machine, Somatom Emotion (Siemens AG, Erlangen, Germany). With the insufflation of carbon dioxide in this study, the attachments and associations change and these were shown to play a role in the movement of the abdominal organs during the manipulations and how the organs come to lie in the abdominal cavity. It was shown that together with the insufflation of carbon dioxide into the abdomen, a very important factor in the movement of the organs was gravity. In certain organs the effect of gravity was found to be the significant factor when the positioning of the animal was changed, more so than the insufflation of the abdomen when PrI and PoI scans were compared. The effects of gravity during the changes in position and the insufflation of the abdomen were compared using a set number of measurements, of organ size and location. The size and location of the organs was compared to set landmarks in the body such as the sternum and certain vertebra, depending on the organ in question. These measurements were compared between the pre- and post-insufflation scans to evaluate the changes that occurred after insufflation with regards to the movement of certain organs and their exposure for a surgical approach. These measurements gave the data an objective value which could then be analysed statistically to determine any significant changes. The p value was set at <0.05 in determining statistical significance using a Kruskal-Wallis one way of variance (ANOVA) and the Tukey-Kramer multiple comparison test. This data was analysed and used to determine the best position to place an animal in order to perform laparoscopic surgery of certain organs. This dissertation showed that the VDR and VDT positions proved much better laparoscopic access to the majority of the parenchymatous organs in the peritoneal cavity than the lateral positions. There were certain organs such as the kidney, the ovaries, the uterine horns and the duodenum that were visualised on CT clear of the rest of the parenchymatous organ mass on the non-dependant part in the respective lateral positions. This indicated that these organs will be easily accessible during laparoscopic surgery in the RL and LL. However no matter what position was used, no position was perfect for every organ of interest, and positions need to be combined for certain procedures. The use of positioning will not remove the need for intra-operative retraction and laparoscopic retractors are an essential part of the surgeon’s arsenal when performing laparoscopic procedures. Copyright / Dissertation (MMedVet)--University of Pretoria, 2011. / Companion Animal Clinical Studies / unrestricted

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