Biliary diseases are uncommon, potentially fatal causes of acute abdomen in dogs. Little information is present comparing the performance of computed tomography (CT) to ultrasound in identifying canine biliary pathology. Thirty-five client-owned dogs presenting for acute abdomen signs received an abdominal ultrasound and contrast-enhanced abdominal CT. Two authors reviewed the randomized, anonymized CT and ultrasound studies. Twenty-eight dogs had biliary pathology and seven dogs serving as controls had no evidence of biliary disease. The final diagnoses of patients with biliary pathology included cholelithiasis, gallbladder mucoceles, cholangiohepatitis/cholangitis, extrahepatic biliary obstruction, gallbladder wall edema, gallbladder wall mass, and cystic mucosal hyperplasia. Computed tomography was more accurate in identifying cholelithiasis than ultrasound. No statistical difference in the odds to identify other biliary pathology was identified between ultrasound and CT. Findings from this study suggest CT may be used in place of ultrasound in canine patients presenting for acute abdominal signs of biliary origin.

Rising temperatures all over the world has correlated with more frequent heat stroke related injuries and death. This statistic not only applies to humans, but to canines as well, who have similar body temperature thresholds. Recent studies have demonstrated that serum histones, released after cell death from heat stroke, play a role in heat stroke related injuries and death. This proposal aims to determine the severity of the effects caused by serum histone release after heat stroke by exposing selected canine cell lines to cell lysate and purified histones H2A, H2B, H3, and H4, which have been found to be associated with heat stroke injuries. Effectiveness of the histones will be determined by measuring the levels of apoptosis, NETosis, and necrosis in the cells, as well as the expression levels of heat shock proteins. Further research will also be done to determine whether toll-like receptors present on the cell surface are responsible for the mechanism utilized by serum histones to damage tissue in the body.

Twelve pairs of cadaveric pelvic limbs were harvested from skeletally mature dogs. Tibias were randomly assigned pairwise to two study groups: locking buttress screw fixation (LBS) and bone-screw-fastener fixation (BSF). A tibial plateau leveling osteotomy (TPLO) was performed. Each specimen was positioned in a servohydraulic testing machine to simulate physiological orientation and loading at the mid-point of the stance phase at the walk. Cyclic loading was performed for 30,000 cycles at 4Hz with a peak-load of 1000N. The cyclic test was then continued by stepwise increasing the peak-load at a rate of 75N per 500 cycles until failure of the construct. The findings of this current study suggest that stabilization of the TPLO with BSF in the proximal part of a locking TPLO plate provided similar biomechanical stability under cyclic axial loading conditions as the LBS. BSF may be an acceptable alternative to LBS for TPLO.

Cyclosporine and prednisone are immunosuppressive drugs that are commonly used in combination for the treatment of immune-mediated diseases, and have been shown to individually cause significant suppression of IL-2. Currently, no studies have been performed to determine how a combination of the two drugs would impact suppression of IL-2, and if an additive or synergistic effect on cytokine production could be demonstrated, as in studies of other species. An additive effect of immunosuppression associated with this drug combination could allow clinicians to decrease dosages of drugs, thereby reducing drug costs and minimizing adverse drug side effects. In a cross-over study design using six healthy dogs, the expression of IL-2 was affected with administration of cyclosporine, prednisone, or a combination of each drug. However, there was no significant difference in the level of immunosuppression compared to cyclosporine alone. Small sample size and the dosages of each drug used potentially affected the strength of the results.

Thirty-two canine tibiae with patellae and patellar tendons were harvested from 17 skeletally mature cadavers. Each tibia was randomly allocated to a construct group: plate and pin (Plate), plate with countersink compression screw (HCS), plate with tension band (TB), or plate with HCS and TB (HCSTB). Samples were loaded by distraction until failure. The stiffness, yield load, and ultimate load were compared between each fixation method. No difference in stiffness of the constructs was detected between groups. Yield load and ultimate load for the HCSTB group was greater than the TB group, the HCS group, and the Plate group. CBLO fixation augmented with a TB and HCS provided a stronger construct that withstood a greater yield load and ultimate load than either augmentation strategy alone. Augmenting a CBLO fixation with a TB and a HCS can provide increased construct strength.

Shelters often make euthanasia or adoption decisions based on the results of FeLV-FIV point-of-care tests but given the low estimated prevalence of these diseases and imperfect test performance, this might not be a good practice because of diagnostic error. The objectives of this study were to determine the true prevalence of FeLV and FIV in apparently healthy and sick shelter cats in Mississippi, estimate predictive value of the Zoetis Witness FeLV-FIV Rapid ImmunoMigration test results at the estimated true prevalences through Bayesian latent class modeling, and formulate testing recommendations for shelters. One chapter will review the literature on FeLV and FIV. The bulk of this thesis will focus on determining the true prevalence of retroviral infection in Mississippi shelter cat populations. The last chapter will use Bayesian modeling to estimate test performance and predictive value of test results in healthy and sick shelter cat populations.