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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

Constructional Fear Treatment for Dogs in Shelters

Katz, Morgan 08 1900 (has links)
Of the approximately 3.9 million dogs that enter US animal shelters each year, many exhibit behaviors related to fear, which can affect their likelihood of adoption. Current dog training procedures to treat fear include counterconditioning and desensitization, which can often take months or years to show any behavior change and do not teach specific behaviors aimed to increase the dog's chance of being adopted. The current study used a negative reinforcement shaping procedure to teach fearful dogs to approach and and interact with people. The results showed that constructional fear treatment increased the amount of time the dog spent at the front of the kennel, and increased sniffing, tail wagging, and accepting petting for all 3 participants.
52

The Relationship between Canine Platelets and Cancer Cells

Bulla, Sandra Curotto 06 May 2017 (has links)
Platelets are small and anucleate blood cells that are well known for their role in hemostasis. Other less recognized platelet functions include contributions to cancer vascularization, growth, and metastasis. Although the participation of platelets in cancer biology has been broadly studied in mouse models, there is no information in the literature regarding the crosstalk of platelets and cancer cells in dogs. The objective of this dissertation was to explore the interaction of canine platelets and tumor cells in vitro. The main hypothesis was that canine platelets were similar to human and murine platelets, and would interact with tumor cells, resulting in a change in the behavior of these cells. Using confocal immunofluorescence, we show that fibrinogen and von Willebrand factor have little colocalization within platelets, providing evidence that canine platelets have selective packaging and different alpha-granule subtypes, as shown in mice and humans. Then, we demonstrate canine platelet activation by osteosarcoma and mammary carcinoma cells, utilizing platelet aggregometry. Next, we show that intact platelets, platelet lysate, and thrombin-activated platelet releasate have an inhibitory effect on the migration of canine osteosarcoma and mammary carcinoma cell lines, contrary to what is described in humans and mice. We also demonstrate that releasate from canine platelets activated by collagen induces cancer cell migration, the opposite of the effect of releasates derived from thrombin or adenosine diphosphate activation. Lastly, we show that platelets can downregulate epithelial-to-mesenchymal-related transcription factors in canine cancer cells, suggesting that platelets may play an important role regulating this process in canine cancer progression. In conclusion, the results of this study have revealed important interactions between canine cancer cell lines and platelets in vitro. Our findings suggest that platelets most likely have a significant role in cancer growth in dogs and that cancer cells most likely affect platelet function in cancer patients.
53

The Effects of Aspirin and Cyclosporine on Canine Platelet Function and Cyclooxygenase Expression

Thomason, John Metcalfe 12 May 2012 (has links)
Immune-mediated hemolytic anemia (IMHA) is one of the most common causes of anemia in dogs. Despite aggressive therapy, there is a 50% mortality rate in IMHA patients, and the most common cause of death is thromboembolic disease, particularly pulmonary thromboembolism. With the high thromboembolism rate in dogs with IMHA, anti-platelet therapy with aspirin can be a life-saving preventative therapy. Along with anti-platelet therapy, immunosuppressive therapy is needed to decrease erythrocyte destruction. Cyclosporine has become a popular medication for immunosuppression in IMHA patients. Unfortunately, recent human reports have suggested that cyclosporine could activate platelets and contribute to a hypercoagulable state. With the goal of improving therapy, these studies investigated the role aspirin plays in inhibiting platelet function and cyclooxygenase expression, an enzyme that enhances platelet reactivity. The effect of cyclosporine on platelet reactivity and hypercoagulablity was investigated to determine if this medication would create activated platelets and a prothrombotic state.
54

Model of extreme hypoglycemia in the ketotic dog

Ciraolo, Susan Taylor January 1994 (has links)
No description available.
55

The diversity of cell types in the neurosecretory system of the American dog tick, Dermacentor variabilis Say (Acarina, Ixodidae) /

Obenchain, Frederick D. January 1970 (has links)
No description available.
56

The effects of sildenafil on portal vein velocity, cross-sectional area, and congestion index in the dog

Tollefson, Christopher 06 August 2021 (has links)
The main use of sildenafil in human medicine is to treat erectile dysfunction. In veterinary medicine, sildenafil is most frequently used to treat pulmonary hypertension. The effects of sildenafil on the portal vasculature in the dog have not been previously evaluated. The purpose of this study was to evaluate the effects sildenafil has on the portal vasculature. The cross-sectional area of the aorta, cross-sectional area of the portal vein, and portal vein velocity were acquired in thirteen dogs prior to administration, 45 minutes, 90 minutes, and 120 minutes after the oral administration of sildenafil for the treatment of pulmonary hypertension. No statistically significant difference was detected between all measured values at all time points. Although this study had a small sample size, sildenafil does not have a significant effect on the size of the portal vasculature. Further studies with a larger sample size will be required to further evaluate the effects.
57

Canine Pure Platelet-Rich Plasma for Regenerative Medicine and Platelet Research: Protocol Optimization

Monobe, Marina Mitie 09 December 2016 (has links)
Platelet-rich plasma (PRP) can be widely used in veterinary medicine in different areas. Studies using PRP frequently use different methodologies making for difficult comparison. The objective of this study was to evaluate the purity and platelet activation of a PRP protocol. A total of 18 blood samples were drawn from six dogs, collected once per week over a total of three weeks. Blood samples were centrifuged six times at 300g for 5 min. Ultra-pure PRP (OP) was obtained by adding PRP a Optiprep 1.063g/mL density barrier and centrifuged at 350g for 15 min. Mean platelet recovery from whole blood was 62.90% in PRP and 45.24% in OP. PRP and OP showed high platelet purity; blood cell contamination <0.01%. Flow cytometry for platelet activation markers was consistent with minimal platelet activation. This study describes the optimization of PRP protocol with high platelet purity, minimal platelet activation, high reliability and reproducibility.
58

Presumptive identification of smooth Brucella strain antibodies in canines

Helms, Alyssa B. 11 October 2021 (has links)
Brucellosis is a zoonotic disease caused by a Gram-negative coccobacillus. There are four Brucella strains of zoonotic importance in our domestic species, subdivided by their culture phenotypes: Brucella abortus (B. abortus, B. melitensis, B. suis (smooth strains) and B. canis (rough strain). Dogs can serve as hosts for all four of the zoonotic strains; however, routine serologic testing in dogs has been limited to the identification of antibodies to B. canis. The aim of our study was to identify a serologic test that can be utilized to identify smooth Brucella strain antibodies in canines. We hypothesize that the Brucella abortus Fluorescence Polarization Assay would be successful in identifying antibodies to smooth Brucella strain in canines. Ninety-five dogs, including forty-five hog hunting dogs were screened for circulating antibodies to any of the four zoonotic strains of the bacteria utilizing a combination of Canine Brucella Slide Agglutination Test (CBSA), Brucella canis Agar Gel Immunodiffusion II test (AGID), Brucella abortus Card Agglutination Test (BCA), and the Brucella abortus Fluorescence Polarization Assay (FPA). Test interpretation results yielded a 0% (0/95) smooth Brucella strain seropositivity rate, with 2% (2/95) of dogs yielding inconclusive rough Brucella strain serology results (0-2% rough strain seropositivity rate). Additionally, a retrospective portion of the study was performed to identify sera containing circulating antibodies to any of the smooth strains of Brucella by testing previously banked canine serum samples stored at Cornell's Veterinary Diagnostic Laboratory from 2018-2019 via Brucella abortus FPA. Of the 769 serum samples tested, 13/769 (1.7%) yielded an inconclusive result, 725/769 (94.2%) were negative, 30/769 (4%) yielded a positive FPA test result, and 1/769 (0.1%) had to be excluded due to insufficient sample remaining to perform the diagnostic test. Of the 30 FPA positive canine serum samples, 97% (29/30) also tested positive on the CBSA test. Additionally, there was a statistically significant (p <0.0001) likelihood of altered (spayed/neutered) and mixed breed dogs to be FPA positive when compared to intact, purebred dogs. / Master of Science / Brucellosis is a bacterial disease that can cause severe reproductive, orthopedic and general illness in both dogs and humans. There are four different species of Brucella that can be transmitted between animals and people: Brucella canis, abortus, suis, and melitensis. Although Brucella canis is the species that is widely recognized and breeding dogs are routinely tested for this strain, we have vastly under recognized the ability for dogs to contract and transmit the other three (smooth) Brucella species. Of added concern is the fact that the test currently used to screen dogs for brucellosis only identifies Brucella canis infection. Thus, veterinarians may be missing cases where dogs are infected with other Brucella species. This study revealed promising evidence in identification of smooth Brucella strain antibodies in canines, particularly altered and mixed breed canines, via the Brucella abortus Fluorescent Polarization Assay. The contributions of this study are threefold. First, to heighten awareness that both smooth and rough strains of brucellosis infection in dogs are infectious diseases of zoonotic concern. Second, it demonstrates that smooth Brucella strain infection along with the traditional strategy of selectively screening dogs breeding dogs may be underestimating the prevalence of brucellosis among the canine population in the United States thus, supporting the need for broadened screening recommendations. Third, it reveals the need for a commercially-available, validated test for the smooth strains of brucellosis in dogs and offers direction for future research efforts to likely focus on the validation of the Brucella abortus Fluorescent Polarization Assay.
59

Shelter to Habitat

Ashworth, Emily Claire 19 July 2021 (has links)
South of the Anacostia River in Washington DC, the Oxon Run park runs through the Washington Highlands and Congress Heights neighborhoods. Though these neighborhoods sit within Ward 8 of DC, which is has the lowest education levels and household incomes, Oxon Run park acts as a lively community magnet, sitting adjacent to the metro station, a vibrant community center, the public pool and multiple schools. One resource that is lacking in Ward 8, similarly to under served communities around the country, is animal care. Pets For Life, an organization that attempts to address this inequity, states "...there are animal resource deserts—entire neighborhoods with no veterinarians, no pet supply stores, no groomers, and no animal welfare infrastructure. When there are no veterinarians in a community, standard wellness care is not the norm—and familiarity, experience, and knowledge concerning common pet health concerns do not exist"¹ This thesis design, Shelter to Habitat, attempts to provide a place for dog care, sheltering, homing and education to a community that needs it. It pushes the definition of sheltering and provides dogs with a space scaled and intentionally designed for their mental and physical health. The design prioritizes light, materiality and airflow to create a space that responds to the life of a dog. It addresses the needs of the community and integrates into the fabric of the neighborhood. The design creates an adaptive building that adjusts to the scale of the dog, while providing a public and private face that addresses the various needs of the community. In this proposed dog shelter design, the 1st floor, which faces the Oxon Run park, acts as the public face of the building. This space houses adoptable dogs, volunteer work spaces, training rooms, and community classrooms. This floor fluctuates the interior-exterior experience by providing a variety of ways to inhabit the spaces. In the main boarding space, the building design scales to the dog, the main user of the space. There are indoor-outdoor runs that penetrate an interior courtyard with wide 12' corridors that circulate the space. The undulation of this boarding space limits the dogs direct views of other dogs in the space, which helps enhance their sense of safety and security. Contrastingly, the 2nd floor acts as a private face of the building, connecting with the 1st floor through a central atrium. On the second floor , medical, quarantine, and short term boarding spaces provide services to the community for lost, sick or rehomed dogs. Together, this public-private, indoor-outdoor design nestles itself into the site and provides a safe, healthy, lively place for both the dogs and the community. Footnotes 1 "Pets for Life Tools and Guides," HumanePro, https://humanepro.org/pets-for-life/tools-and-guides / Master of Architecture / South of the Anacostia River in Washington DC, the Oxon Run park runs through the Washington Highlands and Congress Heights neighborhoods. Though these neighborhoods sit within Ward 8 of DC, which is has the lowest education levels and household incomes, Oxon Run park acts as a lively community magnet, sitting adjacent to the metro station, a vibrant community center, the public pool and multiple schools. This thesis design, Shelter to Habitat, attempts to provide a place for dog care, sheltering, homing and education to a community that needs it. It pushes the definition of sheltering and provides dogs with a space scaled and intentionally designed for their mental and physical health. The design prioritizes light, materiality and airflow to create a space that responds to the life of a dog. It addresses the needs of the community and integrates into the fabric of the neighborhood. The design creates an adaptive building that adjusts to the scale of the dog, while providing a public and private face that addresses the various needs of the community. These intentionally designed connection spaces become a very important part of the building design proposal. There a 3 unique scenarios that need to be considers and designed for when it comes to animal shelter. The first is proving shelter that is scaled to the size of the dog. Juxtaposed to this is hallways and lobbies that are scaled for the overlapping and interacting area of dogs and humans. Finally there are admin and community spaces that are scaled just for the human. These 3 defining scenarios led the design to a dynamic, flexible building that serves a variety of needs.
60

Black-tailed prairie dog declines in northwestern Mexico: species-habitat relationships in a changing landscape

Avila-Flores, Rafael. January 2009 (has links)
Thesis (Ph. D.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on July 23, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Ecology, Department of Biological Sciences, University of Alberta." Includes bibliographical references.

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