Vegetation and soils were evaluated on a black-tailed prairie dog (Cynomys ludovicianus) colony and adjacent non-disturbed mixed-grass prairie in central South Dakota. The study’s objectives were 1) determine differences in plant species diversity and richness, and selected soil quality parameters between prairie dog colonies and adjacent non-disturbed sites, and 2) evaluate impacts of prairie dogs on water infiltration rates. Three soil series were evaluated representing three ecological sites (Opal, Cabba, and Wayden). Plant species richness was higher on the Control on Opal soils, while being lower on the Control on Cabba soils. Lower soil pH and higher nitrate concentrations were found on the prairie dog town for Opal and Cabba soils near the soil surface, close to the prairie dog mounds. These findings show prairie dog impacts on soil parameters can vary across different soil types, which can affect the diversity and richness of vegetative communities within prairie dog colonies.

Rabies is a viral disease caused by the rabies lyssavirus (RABV). Despite effective rabies vaccines for humans and animals, this disease continues to pose a major public health challenge, causing an estimated 59 000 human deaths each year, over 99% of which are caused by the domestic dog (Canis familiaris). Current methods of dog population management used in rabies control programs are ineffective. Surgical sterilisation does not reach enough of the dog population to curb population densities and contraceptives need to be administered at a specific phase in the oestrous cycle or cause a range of side effects. Immunocontraception in dogs would allow rabies vaccination coverage to be maintained, in turn reducing the burden of rabies on public health. The aim of this study was to develop an immunocontraceptive vaccine for dogs capable of eliciting a stronger immune response than that of previously constructed vaccines allowing for effective dog population management and allowing rabies vaccination coverage to be maintain, in turn reducing the burden of rabies on public health. By stabilising the dog population size, the 70% vaccination coverage required to interrupt rabies transmission within a population can be maintained. The immunocontraceptive vaccine constructed in this study contained two reproductive hormones, namely GnRH and kisspeptin, in the hope of eliciting a stronger contraceptive effect than either of these could produce alone, as well as the partial tetanus toxoid gene as an immune stimulant. The nucleic acid GnRH, kisspeptin and partial tetanus toxoid gene (GKT) insert fragment was PCR amplified from a DNA construct (pVAC-GKT) and was cloned into the adenoviral vector using In-fusion cloning technology. Transfection of pAdeno-X 293 cells was confirmed using green fluorescent microscopy and expression of the Ad-GKT mRNA in cell culture was confirmed using real-time RT-PCR. The antigenicity of the Ad-GKT construct was evaluated using female Swiss Webster mice. An indirect ELISA was used to detect seroconversion of the GnRH and Kisspeptin insert fragments. The Ad-GKT construct was successful in eliciting an immune response against GnRH and kisspeptin. Future research should include a comparative study to determine the antigenicity of the Ad-GnRH1 and Ad-GKT constructs in a canine trial for potential use in rabies control programs. / Dissertation (MSc (Microbiology))--University of Pretoria, 2021. / The Poliomyelitis Research Foundation grant (19/89). University of Pretoria postgraduate masters research bursary. Technology Innovation Agency Seed Fund. National Research Foundation grant (122016). / Microbiology and Plant Pathology / MSc (Microbiology) / Restricted

Computed tomography (CT) is an imaging technique that uses x-ray and computers to create cross-sectional images of structures. Stereotactic CT-guided biopsy is defined as the use of a stable apparatus to direct and perform tissue biopsies under CT guidance. For the brain, the principal advantage of stereotactic CT guidance over other biopsy techniques is its high accuracy in getting a sample from deep-seated lesions. The objectives of this study were to create an inexpensive CT-guided stereotactic device adaptable to different canine head sizes and to test the accuracy of the device for needle placement in deep-seated brain targets. A biopsy device was created that consists of four main components: a CT table fixation device, a head fixture, a needle fixture , and motion control system. Accuracy was tested using 16 head and neck specimens obtained from dogs euthanitized for reasons unrelated to the brain. Deep-seated (caudate nucleus and pituitary gland) targets were identified on CT. After a 5 mm craniotomy, the biopsy needle, with CT monitoring, was progressively introduced into the target. The final needle track distance was measured on CT. The brain was removed and sliced to verify placement of the needle tip within the target and to measure the actual needle track distance. The total cost of materials and construction for the stereotactic CT-guided biopsy device was $785.00. No difference in needle placement accuracy was identified for caudate and pituitary targets. Based on assessments by 2 independent observers, the caudate target was successfully hit 75% of the time. Pituitary targets were successfully hit 96.8 % of the time. Actual needle track lengths were an average of 3.2 mm less that the track length measured on CT. This difference was most likely due to incomplete staining of the bevel part of the needle track on gross specimens. / Master of Science

Cyclosporine is used in veterinary medicine to treat a number of inflammatory and immune-mediated conditions, however firm oral dosing protocols have yet to be established in the dog. Traditionally a pharmacokinetic approach, through measurement of blood drug concentrations, has been the primary method of establishing if the given dose is effectively suppressing the immune system. However, there is some debate over how well blood drug concentrations correspond to immunosuppression, since individuals can vary in response to the same drug concentration. Our research group believes that a pharmacodynamic approach could alternatively be used to accurately determine cyclosporine dosages in individual patients since this will give a measurement of the immune system’s response to the drug, rather than simply how the body is processing it. This method will give a more accurate assessment of the patient’s immune system, and allow for better immunosuppressant therapy. The objective of this thesis was to develop a quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay that could reliably predict patient outcome during cyclosporine treatment. This assay would essentially work as a diagnostic tool that clinicians can use to help determine if they were using an appropriate cyclosporine dose for their patients. The assay measures cytokine expression of activated T cells, which are the target cell for the active metabolite of cyclosporine. Our objectives were achieved, firstly, through validation of the assay. Since this assay will be used by clinicians throughout the nation, we first established if shipping conditions affected the sample, and therefore assay results. Once the effect of sample storage time and temperature were determined, optimal sample collection timing was established. Finally, cytokine levels were measured in samples from clinical cases and healthy control dogs to examine the difference in cytokine expression between these two groups. An effective and reliable treatment method for cyclosporine has yet to be established in the dog; therefore the results of this thesis will lead to better therapeutic monitoring and more efficient use of cyclosporine therapy in canine patients.

Prostaglandin F2a (PGF2a), oxytocin and gonadotropin releasing hormone (GnRH) have been used in bulls, rams, boars, stallions or rodents to increase sperm numbers in the ejaculate. Improving sperm quantity in the canine ejaculate would benefit all assisted reproductive techniques used in this species. The purpose of the present study was to evaluate the effects of PGF2a, oxytocin and GnRH on canine ejaculate characteristics. Eight, mature, medium size (25-30 kg), mixed breed dogs were randomly assigned to one of four treatment groups (N=2 dogs each); each group received one treatment per week for four weeks. Treatments were assigned based on a Latin Square design. A two-week training period was used to acclimate the dogs to manual semen collection. Treatments were 0.1 mg/kg PGF2a 15 minutes prior to collection, 2.5 units/dog oxytocin 10 minutes prior to collection, 50 mg/dog GnRH 60 minutes prior to collection, or 1.0 ml of saline 30 minutes prior to collection. An evaluator that was blinded to treatment analyzed ejaculate characteristics. Samples were evaluated for semen volume, concentration of spermatozoa per milliliter, motility, morphology, total sperm number and total morphologically normal motile sperm number (TNMS). In addition, a subjective ease of collection score was assigned following each collection (Scale 1-9, 1 being easiest to manually ejaculate). Semen concentration, motility and morphology were not different between treatments. Semen volume was greater for dogs treated with PGF2a or oxytocin compared to saline. Total sperm number and TNMS were greater when dogs were treated with PGF2a compared to oxytocin, GnRH and saline (p<0.05). The subjective ease of collection score was lower for dogs receiving PGF2a compared to GnRH or saline (p<0.05). In summary, administration of PGF2a or oxytocin prior to semen collection increased semen volume and PGF2a increased total sperm number in the ejaculate of the dog. It did not appear that treatment with GnRH had an effect on semen parameters evaluated in this study. / Master of Science

Yes / Dog bite injuries are a common cause of patient presentation to NHS emergency departments (EDs) and minor injuries units, and are generally associated with a low level of acuity, despite an inherent capacity for significant soft tissue damage to be inflicted by canine jaws capable of exerting terrific bite forces. Anatomical sites for injury correlate to victim age, with hand and wrist injuries predominating in the adult population. The most common complication is infection secondary to inoculation of oral flora, with the hands being particularly vulnerable due to their anatomy. Injuries to structures such as tendons can be discreet, and retained foreign bodies can easily be overlooked. Wound care has a propensity to attract a disproportionately high level of malpractice actions, and approaches to the management of dog bite injuries have largely been empirical, which may render the practitioner particularly exposed. In response to increasing pressures on healthcare systems, paramedics with extended scopes of practice, including wound care and suturing, are being utilised to assess, manage, treat, and either refer or discharge patients with apparently minor injuries, in strategies aimed at reducing hospital admissions. This article adopts a case study format to examine and evaluate treatment modalities and the current evidence base informing best practice in terms of dog bite injuries from the perspective of a paramedic practitioner, with critical reflection on the decision making process and complexities of such episodes of care in the pre-hospital setting.

Concurrent meniscal injury in dogs with cranial cruciate ligament tears ranges from 10-70%, and these injuries can increase the risk of developing osteoarthritis. Studies regarding joint space width on knee radiographs in people have indicated correlations between joint space width and meniscal injuries. The aim of this study was to determine if there was correlation between stifle joint space width on three different radiographic projections and meniscal injuries identified at surgery in dogs. Four blinded observers measured the radiographic joint space width three times, and the measurements were compared to surgical findings. Intraclass correlation coefficients for inter- and intraobserver variability ranged from moderate to excellent. There was significance between dogs with a meniscal tear and the corresponding joint space width on standard TPLO lateral radiographic projections. Joint space narrowing is seen with meniscal tears in dogs, and radiography may be a noninvasive way to identify meniscal tears prior to surgery.

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