Below, please find a list of our clinical trials that we have completed involving dogs.


  • Frequency of Parvovirus in Vaccinated Puppies that Attended Puppy Socialization Classes
  • Outcome: Socialization is one method of preventing behavior problems in dogs; however, some oppose socialization before 16 wk of age due to the risk of contracting infectious diseases. The objectives of this study were to determine if puppies that attended puppy socialization classes and were vaccinated by a veterinarian at least once were at an increased risk of confirmed canine parvovirus (CPV) infection compared with puppies that did not attend classes and to determine the frequency of suspected CPV infection in puppies vaccinated at least once that attended classes with trainers. Twenty-one clinics in four cities in the United States provided information regarding demographics, vaccination, CPV diagnosis, and class attendance for puppies ≤ 16 wk of age. In addition, 24 trainers in those same cities collected similar information on puppies that attended their classes. In total, 279 puppies attended socialization classes and none were suspected of or diagnosed with CPV infection.

    Impact of the study: Results indicated that vaccinated puppies attending socialization classes were at no greater risk of CPV infection than vaccinated puppies that did not attend those classes.

    Publications: Stepita, M.E., Bain, M.J., & Kass, P.H. (2013). Frequency of CPV Infection in Vaccinated Puppies that Attended Puppy Socialization Classes. Journal of the American Animal Hospital Association, 49(2), 95-100. (DOI:1053526/JAAHA-MS-5825)

  • Owner Attachment and Problem Behaviors Related to Relinquishment and Training Techniques of Dogs
  • Outcome: Problematic behaviors are a significant reason for relinquishment, and relinquished dogs are more likely to have problem behaviors. This study utilized standardized surveys of owners (companion animal guardians) relinquishing their dogs to shelters and dog owners visiting vaccination clinics. "Relinquishing" and "continuing" owners were asked questions in the following categories: demographic information, training methods and tools, frequencies in which their dogs engaged in problematic behaviors, and attachment to their dogs. "Relinquishers"; were also asked to provide their reasons for relinquishment. The results of 129 surveys (80 relinquishing and 49 continuing) showed that relinquishers scored lower on companion animal attachment than continuing owners. Pit bull-type dogs were represented more in the relinquishing group. Relinquished dogs were no less likely to have attended training classes than continuing dogs. In both groups, owners who used punishment-based collars reported less satisfaction with their dogs' overall and leash-walking behaviors. Pit bull-type dogs were reported to be no less well behaved compared with all other breeds combined. Sixty-five percent of relinquishers reported some behavioral reason for relinquishment. Forty-eight percent of relinquishers indicated that at least 1 problem behavior was a strong influence on their decision to relinquish.

    Impact of the study: Not applicable

    Publications: Kwan, J.Y., & Bain, M.J. (2013). Owner Attachment and Problem Behaviors Related to Relinquishment and Training Techniques of Dogs. Journal of Applied Animal Welfare Science, 16(2), 168-83. (DOI:10.1080/10888705.2013.768923)

  • Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers
  • Outcome: In contrast to European countries, the overwhelming majority of dogs in the U.S. are neutered (including spaying), usually done before one year of age. Given the importance of gonadal hormones in growth and development, this cultural contrast invites an analysis of the multiple organ systems that may be adversely affected by neutering. Using a single breed-specific dataset, the objective was to examine the variables of gender and age at the time of neutering versus leaving dogs gonadally intact, on all diseases occurring with sufficient frequency for statistical analyses. Given its popularity and vulnerability to various cancers and joint disorders, the Golden Retriever was chosen for this study. Veterinary hospital records of 759 client-owned, intact and neutered female and male dogs, 1–8 years old, were examined for diagnoses of hip dysplasia (HD), cranial cruciate ligament tear (CCL), lymphosarcoma (LSA), hemangiosarcoma (HSA), and mast cell tumor (MCT). Patients were classified as intact, or neutered early (<12 mo) or late (≥12 mo). Statistical analyses involved survival analyses and incidence rate comparisons. Outcomes at the 5 percent level of significance are reported. Of early-neutered males, 10 percent were diagnosed with HD, double the occurrence in intact males. There were no cases of CCL diagnosed in intact males or females, but in early-neutered males and females the occurrences were 5 percent and 8 percent, respectively. Almost 10 percent of early-neutered males were diagnosed with LSA, 3 times more than intact males. The percentage of HSA cases in late-neutered females (about 8 percent) was 4 times more than intact and early-neutered females. There were no cases of MCT in intact females, but the occurrence was nearly 6 percent in late-neutered females.

    Impact of the study: The results have health implications for Golden Retriever companion and service dogs, and for oncologists using dogs as models of cancers that occur in humans.

    Publications: Torres de la Riva, G., Hart, B.L., Farver, T.B., Oberbauer, A.M., Messam, L.L.M., Willits, N., & Hart, L.A. (2013). Neutering Dogs: Effects on Joint Disorders and Cancers in Golden Retrievers. Public Library of Science One, 8(2), e55937. (DOI:10.1371/journal.pone.0055937)

  • Evaluation of Owner Attachment to Dogs on the Basis of Whether Owners are Legally Considered Guardians of Their Pets
  • Outcome: The degree to which owners were attached to their dog was associated with city of residence, owner age, and whether owners were completely satisfied with their dog's behavior. Owners residing in the guardian city had a lower attachment score. There was no significant difference in the percentage of dogs vaccinated against rabies in each city, nor was there any difference in the percentage of licensed dogs. Attachment scores did not differ between participants who visited mobile versus free-standing clinics. Owners with > 1 dog in their household reported a higher degree of attachment to the study dog than did owners of 1 dog.

    Impact of the study: Dog owners residing in a city where owners were legally designated as an owner/guardian were no more attached to their dog than those living in a city without such a designation. Although results did not indicate a negative impact of the term guardian, its use was not associated with an enhanced bond between owner and dog.

    Publications: Helms, T.D. & Bain, M.J. (2009). Evaluation of owner attachment to dogs on the basis of whether owners are legally considered guardians of their pets. Journal of the American Veterinary Medical Association, 234(7), 896-900. (DOI:10.2460/javma.234.7.896)

  • Evaluation of a Behavioral Assessment Questionnaire for Use in the Characterization of Behavioral Problems of Dogs Relinquished to Animal Shelters
  • Outcome: Analyses revealed significant differences in 2 areas of reported problem behavior between the confidential and nonconfidential information groups: owner-directed aggression and stranger-directed fear. Compared with client-owned–group data, significantly more relinquished shelter dogs in the confidential information group were reported to have ownerdirected aggression, stranger-directed aggression, dog-directed aggression or fear, stranger-directed fear, nonsocial fear, and separation-related behaviors.

    Impact of the study: Among persons relinquishing dogs to a shelter, those who believed questionnaire responses were confidential reported owner-directed aggression and fear of strangers in their pets more frequently than relinquishers who believed responses were nonconfidential. Confidentiality had no apparent effect on the reporting of other assessed behavioral problems. Results suggest that behavioral questionnaires may sometimes provide inaccurate information in a shelter setting, but the information may still be useful when evaluating behavior of relinquished dogs.

    Publications: Segurson, S.A., Serpell, J.A., & Hart, B.L. (2005). Evaluation of a behavioral assessment questionnaire for use in the characterization of behavioral problems of dogs relinquished to animal shelters. Journal of the American Veterinary Medical Association, 227(11), 1755-61. (DOI:10.2460/javma.2005.227.1755)

  • Effect of Gonadectomy on Subsequent Development of Age-Related Cognitive Impairment in Dogs
  • Outcome: Sexually intact male dogs were significantly less likely than neutered dogs to progress from mild impairment (i.e., impairment in 1 category) to severe impairment (i.e., impairment in 2 categories) during the time between the first and second interviews. This difference was not attributable to differences in ages of the dogs, duration of follow-up, or the owners' perceptions of the dogs' overall health.

    Impact of the study: Results suggest that the presence of circulating testosterone in aging sexually intact male dogs may slow the progression of cognitive impairment, at least among dogs that already have signs of mild impairment. Estrogens would be expected to have a similar protective role in sexually intact female dogs; unfortunately, too few sexually intact female dogs were available for inclusion in the study to test this hypothesis. There may be a need to evaluate possible methods for counteracting the effects of loss of sex hormones in gonadectomized dogs.

    Publications: Hart, B.L. (2001). Effect of gonadectomy on subsequent development of age-related cognitive impairment in dogs. Journal of the American Veterinary Medical Association, 219(1), 51-56. (DOI:10.2460/javma.2001.219.51)

  • Prevalence of Behavioral Changes Associated with Age-Related cCgnitive Impairments in Dogs
  • Outcome: Age by sex interactions for dogs with impairment in any category were not significant, and, therefore, data on castrated males and spayed females were pooled for analyses across ages. The prevalence of age-related progressive impairment was significant in all categories. The percentage of 11- to 12-year-old dogs with impairment in 1 category was 28% (22/80), of which 10% (8/80) had impairment in 2 or more behavioral categories. Of 15- to 16-year-old dogs, 68% (23/34) had impairment in 1 category, of which 35% (12/34) had impairments in 2 or more categories. There were no significant effects of body weight on the prevalence of signs of dysfunction in the behavioral categories.

    Impact of the study: Data collected provide estimates of the prevalence of various degrees of age-related behavioral changes associated with cognitive dysfunction in dogs. Age-related behavioral changes may be useful indicators for medical intervention for dogs with signs of cognitive impairment.

    Publications: Neilson, J.C., Hart, B.L., Cliff, K.D., & Ruehl, W.W. (2001). Prevalence of behavioral changes associated with age-related cognitive impairment in dogs. Journal of the American Veterinary Medical Association, 218(11), 1787-91. (DOI:10.2460/javma.2001.218.1787)

  • Predicting Behavioral Changes Associated with Age-Related Cognitive Impairment in Dogs
  • Outcome: Between interviews, 22% (16/73) of dogs that did not have impairment in a category at the time of the first interview developed impairment in that category by the time of the second interview. Forty-eight percent (13/27) of dogs that had impairment in 1 category at the time of the first interview developed impairment in 2 or more categories by the time of the second interview and were significantly more likely to develop impairment in 2 or more categories, compared with dogs that initially had impairment in 0 categories. Dogs with 1 sign of dysfunction in orientation were significantly more likely to develop impairment in that category, compared with dogs that had 0 signs of dysfunction in orientation.

    Impact of the study: Age-related behavioral changes in dogs are progressive. Clinicians should consider trying to predict which dogs are most likely to become progressively impaired during the subsequent 6 to 18 months.

    Publications: Bain, M.J., Hart, B.L., Cliff, K.D. & Ruehl, W.W. (2001). Prevalence of behavioral changes associated with age-related cognitive impairment in dogs. Journal of the American Veterinary Medical Association, 218(11), 1792-5. (DOI:10.2460/javma.2001.218.1792)


  • Use of Diphenhydramine to Reduce Fewer Infusion-Related Ventricular Arrhythmias in Dogs Treated with Doxorubicin
  • Purpose: The current recommendation for canine lymphoma treatment includes the use of a chemotherapy drug called doxorubicin. Although effective, one of the reported side effects of doxorubicin is the liberation of a molecule called histamine, which can cause ventricular arrhythmias (an irregular rhythm). The concurrent use of anti-histamine agents like diphenhydramine (commonly known as Benadryl) with doxorubicin therapy could possibly reduce these abnormal beats. Therefore, the aim of this study was to see if use of diphenhydramine can reduce the risk of arrhythmias sometimes associated with the administration of chemotherapy.

  • Echocardiographic Effects of Butorphanol and Atenolol in Dogs with Subaortic or Pulmonic Stenosis
  • Purpose: Pulmonic stenosis (PS) and subaortic stenosis (SAS), the two most common congenital heart defects encountered in dogs, are characterized by a narrowing of the outlet of the right or left side of the heart, respectively. We were studying the effects of two commonly utilized medications – butorphanol, a mild sedative commonly used to help facilitate heart ultrasounds and atenolol, a beta-blocker commonly utilized to help treat PS and SAS – on heart function and assessment of disease severity in dogs with PS and SAS.

  • The Role of Genetics in Canine Pulmonary Hypertension and the Response to Standard Treatment with Sildenafil
  • Purpose: We were investigating the role of a common canine genetic variant on the condition of pulmonary hypertension. This genetic variant was being evaluated to see if it impacted the severity of disease or the response to the oral medication, sildenafil citrate, the most commonly used drug for the treatment of this condition. Information provided by this study will provide better guidelines for the treatment of dogs with pulmonary hypertension.

  • Acute Effects of Sotalol on Echocardiographic Indices of Ventricular Function in Dogs with Ventricular Tachyarrhythmias
  • Purpose: Sotalol is considered by most veterinary cardiologists to be one of the most effective and well-tolerated medications for longterm control of potentially life-threatening ventricular arrhythmias (abnormal and rapid heartbeats arising from the pumping chambers). Sotalol may decrease heart function (pumping ability) but it is currently unknown to what extent, if any, it does so. Therefore, the purpose of this clinical trial was to determine the effect of a single standard dose of sotalol on heart function and rhythm in dogs diagnosed with ventricular arrhythmias.

  • A Single Codon Insertion in PICALM is Associated with Development of Familial Subvalvular Aortic Stenosis in Newfoundland Dogs
  • Outcome: "Familial subvalvular aortic stenosis (SAS) is one of the most common congenital heart defects in dogs and is an inherited defect of Newfoundlands, golden retrievers and human children. Although SAS is known to be inherited, specific genes involved in Newfoundlands with SAS have not been defined" (Stern et al. 2014). After examining over 300 dogs, Dr. Stern identified a mutation in the phosphatidylinositol-binding clathrin assembly protein (PICALM), a protein that is found in the canine heart, that is associated with the development of SAS in Newfoundland dogs and determined that this particular mutation is passed down to their puppies.

    Impact of the study: The ability to test for presence of this PICALM insertion may impact dog-breeding decisions and facilitate reduction of SAS disease prevalence in Newfoundland dogs. Understanding the role of PICALM in OFT development may aid in future molecular and genetic investigations into other congenital heart defects of various species (Stern et al. 2014).

    Publications: Stern, J.A., White, S.N., Lehmkuhi, L.B., Reina-Doreste, Y., Ferguson, J.L., Nascone-Yoder, N.M., & Meurs, K.M. (2014). A single codon insertion in PICALM is associated with development of familial subcalvular aortic stenosis in Newfoundland dogs. Human Genetics, 133(9), 1139-48. (DOI 10.1007/s00439-014-1454-0)

    Genetic Tests: Coming soon to the UC Davis Veterinary Genetics Laboratory!

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Dentistry and Oral Surgery

  • The Diagnostic Yield of Dental Radiographs and Cone-Beam Computed Tomography in Brachycephalic Dogs with Dental Disorders
  • Purpose of Study: Because of the highly detailed images, cone-beam computed tomography (CBCT) scans are commonly used as diagnostic tools in human medicine with great success; however, these scans are only now being introduced to the veterinary field. Therefore, the purpose of this study was to establish CBCT scans as the ideal imaging modality for brachycephalic dogs with dental disorders.


  • A Pilot Study of the Efficacy of a Bruton’s Tyrosine Kinase Inhibitor (BTKi) in the Treatment of Dogs with Pemphigus Foliaceus (PF)
  • Purpose of Study: Although it is a rare skin disease, pemphigus foliaceus (PF) is the most common form of pemphigus and probably the most common cutaneous autoimmune disease in the dog. The goal of this study is to assess the efficacy of a Bruton’s Tyrosine Kinase inhibitor (BTKi) as a therapy for canine pemphigus foliaceus (as pills which can also be crushed into powder in food if necessary).


  • Addison's Disease in Nova Scotia Duck Tolling Retrievers (NSDTRs)
  • Purpose: Addison’s disease in the Nova Scotia Duck Tolling Retriever (NSDTR) has a complicated presentation, as the disease manifests as early as 7 weeks of age and as old as 11 years, and in some cases, can be observed in conjunction with other diseases (e.g., hypothyroidism, immune-mediated polyarthritis, and various eye problems). Sequencing of the canine genome allowed scientists to create powerful new tools (e.g., SNP arrays) to investigate inherited diseases. Previous studies found a significantly associated chromosomal region in dogs affected with Addison’s disease under 1 year of age. We were investigating a candidate causal mutation for the juvenile onset form of the disease within that same region.

  • Identifying the Genes Responsible for Hypertrophic Osteodystrophy in Weiaraners and Other Susceptible Breeds
  • Purpose of Study: The purpose of this study was to identify the molecular basis for the bone disease, hypertrophic osteodystrophy.

  • Understanding the Genetic Basis of Cleft Lip and/or Cleft Palate in Dogs
  • Purpose of Study: Cleft lip and/or cleft palate are developmental defects that result in the failure of the roof of the mouth to properly form. This results in an inability to properly nurse and often leads to euthanasia. The aim of this study was to identify the genes responsible for these birth defects and prevent them in future litters.

Internal Medicine

  • Evaluation of Post-Dexamethasone Cortisol Value Used to Diagnose Hyperadrenocorticism in Dogs
  • Purpose of Study: The cut off values previously used to diagnose hyperadrenocorticism, or Cushing’s disease, were first determined over 30 years ago. Since then, there have been significant advancements in laboratory equipment and techniques as well as the clinician’s ability to identify this disease as a differential diagnosis. The goal of this study is to re-evaluate the cut off values used to diagnose hyperadrenocorticism in dogs.

  • Immunomodulation by Mesenchymal Stem Cells In Canine Inflammatory Bowel Disease
  • Purpose of Study: Inflammatory bowel disease (IBD) in dogs often involves lifelong steroid therapy, which holds the risk for a variety of potentially serious complications. Because of the ability to regulate immune responses and facilitate tissue regrowth or repair, we believe that fat-derived, mesenchymal stem cells (MSCs) may help to decrease the abnormal immune response and the accompanying inflammation. Therefore, the purpose of this study was to investigate the effectiveness of a new stem cell therapy for canine IBD and better understand how stem cells work to limit inflammation and repair gut tissue.

  • Use of Canine Struvite Dissolution Diet in the Management of Infection Induced Struvite Stones in Dogs
  • Purpose: We hoped to provide another option to struvite stone dissolution in dogs. The purpose of this trial was to evaluate the efficacy of a therapeutic diet for struvite dissolution in dogs.

    The trial closed January 2018.

  • Clinical and Pathological Characterization of Upper Airway Syndrome in Norwich Terriers
  • Purpose: Upper airway obstruction in the Norwich Terrier is a devastating respiratory disorder that can limit exercise ability and even lead to collapse. The purpose of this trial evaluated the upper airway in a large group of Norwich Terriers (with and without obvious clinical abnormalities) and to characterize the genetics of this condition.

  • Evaluation of the Live Biotherapeutic Product, Asymptomatic Bacteria, E. coli 2-12, in Dogs with Recurrent UTI
  • Purpose: Recurrent (more than 3 per year) urinary tract infections (UTI) are problematic for dogs and continual administration of antimicrobial therapy could lead to bacteria becoming resistant. Therefore, the purpose of this trial was to investigate a novel non-antibiotic treatment for recurrent UTIs in dogs.

Neurology and Neurosurgery

  • Genome-Wide Association Analysis Identifies a Mutation in the Thiamine Transporter 2 (SLC19A3) Gene Associated with Alaskan Husky Encephalopathy.
  • Outcome: Alaskan Husky Encephalopathy (AHE) has been previously proposed as a mitochondrial encephalopathy based on neuropathological similarities with human Leigh Syndrome (LS). We studied 11 Alaskan Husky dogs with AHE, but found no abnormalities in respiratory chain enzyme activities in muscle and liver, or mutations in mitochondrial or nuclear genes that cause LS in people. A genome wide association study was performed using eight of the affected dogs and 20 related but unaffected control AHs using the Illumina canine HD array. SLC19A3 was identified as a positional candidate gene. This gene controls the uptake of thiamine in the CNS via expression of the thiamine transporter protein THTR2. Dogs have two copies of this gene located within the candidate interval (SLC19A3.2 – 43.36–43.38 Mb and SLC19A3.1 – 43.411–43.419 Mb) on chromosome 25. Expression analysis in a normal dog revealed that one of the paralogs, SLC19A3.1, was expressed in the brain and spinal cord while the other was not. Subsequent exon sequencing of SLC19A3.1 revealed a 4bp insertion and SNP in the second exon that is predicted to result in a functional protein truncation of 279 amino acids (c.624 insTTGC, c.625 C>A). All dogs with AHE were homozygous for this mutation, 15/41 healthy AH control dogs were heterozygous carriers while 26/41 normal healthy AH dogs were wild type. Furthermore, this mutation was not detected in another 187 dogs of different breeds.

    Impact of the study: These results suggest that this mutation in SLC19A3.1, encoding a thiamine transporter protein, plays a critical role in the pathogenesis of AHE.

    Publications: Vernau, K., Runstadler, J.A., Brown, E.A., Cameron, J.M., Juson, H.J., Higgins, R.J., Ackerley, C., Sturges, B.K., Dickinson, P.J., Purschner, B., Giulivi, C., Shelton, D., Robinson, B.H., DiMauro, S., Bollen, A.W., & Bannasch, D. (2013). Genome-Wide Association Analysis Identifies a Mutation in the Thiamine Transporter 2 (SLC19A3) Gene Associated with Alaskan Husky Encephalopathy. Public Library of Science One, 8(3): e57195. (DOI:10.1371/journal.pone.0057195)

    Genetic Tests: DNA test for Alaskan Husky Encephalopathy


  • CT and PET/CT for staging of canine oral malignant melanoma
  • Purpose of Study: Melanoma is the most common malignant tumor of the mouth in dogs. This tumor has a relatively high rate of metastasis (tumor spread) and detection of metastasis is important as it can impact prognosis. In human medicine, staging (looking for metastasis) for similar head and neck tumors regularly includes the functional imaging positron emission tomography (PET) combined with computed tomography (CT). Currently, there is no standardized approach in veterinary medicine to assess for metastasis in oral malignant melanoma in dogs. Previous research has found the feeling of lymph nodes on examination can be an inaccurate assessment for cancer spread as they can be normal in size and still contain tumor cells. Therefore, the purpose of this study was to compare lymph node palpation to the appearance of the local lymph nodes on CT scan and a combined PET/CT scan to histopathologic results to determine which method may be the most reliable for identification of metastatic (tumor filled) lymph nodes.

  • Evaluation of Oral Rapamycin for Treatment of Dogs with Osteosarcoma
  • Purpose of Study: Standard therapy for dogs diagnosed with osteosarcoma has long been amputation of the affected limb followed by chemotherapy to prevent the spread of cancer. With this form of treatment, survival times of dogs diagnosed with osteosarcoma is on average about 10 to 12 months with little improvement in survival occurring over the past two decades. Rapamycin is a drug that potentially can inhibit an important pathway in cancer progression known as mTOR. The purpose of this study was to determine if adding the oral drug Rapamycin into the treatment protocol for dogs with osteosarcoma will be safe and improve efficacy of current standard therapies for osteosarcoma in dogs.

  • Radiation and Autologous Natural Killer Immunotherapy in Canine Osteosarcoma
  • Purpose of Study: Even when we can get local control of osteosarcoma, most dogs will die of their disease within a year even if they have amputation and chemotherapy. The goal was to see if we can slow or stop the formation of lung metastasis (spread of tumor to your dog’s lungs which occurs in over 90% of cases).

  • Use of Tanovea-CA1™ in Dogs with Lymphoma, Multiple Myeloma, or Lymphoid Leukemia
  • Purpose of Study: Recent studies in dogs with lymphoid cell neoplasia have demonstrated the safety and efficacy of Tanovea-CA1™ and have led to its conditional FDA approval. To build on these studies, further clinical evaluation of Tanovea-CA1™are needed. The purpose of this study was to expand on previous data documenting clinical benefit in dogs with lymphoid leukemia and multiple myeloma/plasma cell tumors.

  • Pre-clinical Evaluation of Intratumoral Plasmid IL-12 + Electroporation in Dogs with Spontaneous Soft Tissue Sarcoma
  • Purpose of Study: We have been evaluating ways to activate the immune system into recognizing that a tumor is foreign and attacking it. The purpose of this study is to determine if injecting this investigational drug (Interleukin-12 plasmid or pIL-12 that is administered using electroporation) prior to surgery will help activate the immune system and help stop the tumor from coming back or spreading. This therapy is under investigation in the United States for treatment of cancer and has not been approved for sale by the US FDA for human or veterinary use.

  • Radioimmunotherapy for Metastatic Sarcomas and Melanomas
  • Purpose of Study: The purpose of this study was to develop better methods to treat advanced cancer, specifically to find ways to activate the immune system to attack cancer.

  • CT-based Pulmonary Gas Exchange Imaging
  • Purpose of Study: The overall goal of this project was to develop and investigate a novel functional imaging technique for pulmonary function (gas exchange) based on computed tomography (CT) to increase therapeutic gains of lung cancer radiotherapy. Specifically, to develop a physiologically accurate CT-based gas exchange imaging technique. The long-term goal of the study was (1) to reduce pulmonary toxicity of radiotherapy to healthy lung tissue (2) and make the CT gas exchange imaging available for routine use in radiotherapy. There is no radiotherapy included in this study. It was done to gather preliminary data and is funded by the RSNA (Radiological Society of North America).

  • Open-Label, Rabacfosadine (VC-007) for Injection in Dogs with Lymphoma
  • Purpose of Study: Lymphoma, the most common hematopoietic tumor of dogs, is an aggressive disease. Although studies in dogs with lymphoma have demonstrated the safety and efficacy of Rabacfosadine (VC-007), a limited number of dogs have been treated once every three weeks. Furthermore, anecdotal reports suggest reduction in the incidence and severity of adverse effects when used with concurrent low-dose corticosteroid therapy. For this reason, clinical evaluation of Rabacfosadine (VC-007) given once every 21 days was be performed in dogs with lymphoma.

  • COTC020: Evaluation of Orally Administered mTOR inhibitor Rapamycin in Dogs with Osteosarcoma and Soft Tissue Sarcoma
  • Purpose of Study: This clinical trial evaluated the safety and effectiveness of rapamycin when given to dogs with osteosarcoma or soft tissue sarcomas. Rapamycin is a drug currently approved for immunosuppression during preparatory and maintenance regimens for organ and bone marrow transplant in human patients. Early work with rapamycin suggests that this agent may also have anti-cancer properties by inhibiting (reducing the effects of) an important pathway in cancer progression known as mTOR. Preclinical studies of rapamycin in mice as well as recent data using analogous drugs in human patients (rapalogs) suggest that mTOR blockade may be effective in the treatment of several cancers, including osteosarcoma and soft tissue sarcoma.

  • COTC007b: Preclinical Comparison of Three Indenoisoquinolines Candidates in Tumor-Bearing Dogs
  • Purpose of Study: This clinical trial assessed the safety and effectiveness of three newly developed chemotherapy agents (indenoisoquinolines) when given to dogs with lymphoma. Although this class of compounds has shown efficacy in a variety of cancers, interest in developing new topoisomerase I inhibitors, indenoisoquinolines, are currently being evaluated in human patients as agents with improved drug stability and measurable blood levels. This study was the first time the indenoisoquinolines are being assessed in dogs with cancer.

  • COTC026: Using New Technology to Assess Tumor Extent in Dogs with Anal Sac Adenocarcinoma
  • Apocrine gland anal sac adenocarcinoma is the most common malignant tumor of the anal sac in dogs. Currently, fine needle aspirates or histopathology with surgical removal of local lymph nodes is necessary to definitively diagnose tumor spread. Multiple imaging modalities have been used to evaluate for metastasis in anal sac adenocarcinoma, but no standardized approach has been established. The aim of this study was to determine whether the combination of CT and PET is is more accurate for identification of tumor as well as tumor spread than CT alone.


  • Comparison of Longitudinal Changes in Chromatic Pupillometry in Normal Dogs and Dogs with Sudden Acquired Retinal Degeneration or Optic Pathway Disease
  • Purpose of Study: Sudden acquired retinal degeneration syndrome (SARDS) is a common cause of permanent blindness in dogs. However, the underlying cause for SARDS is unknown and no treatment exists. Dogs usually become rapidly blind with no obvious structural abnormalities in the eye itself. We were interested in better understanding this devastating disease, and especially how it changes over time with hopes of identifying better methods for diagnosing SARDS, differentiating it from other similar diseases, monitoring dogs with this disease, and eventually to aid in evaluation of treatments when they become available.

  • Finding the Best Sample Collection Method for Infectious Keratitis in Dogs
  • Purpose of Study: If your veterinarian has a suspicion that your pet is suffering from infectious keratitis (infection of the cornea) or a deep corneal ulcer, they will recommend taking a swab sample from the surface of your pet’s cornea in order to see what type of infection your pet has. Historically at UC Davis, we have used a topical anesthetic named proparacaine, that is applied to the surface of the eye before any samples are taken to minimize discomfort. Recently, a concern has been raised that proparacaine may inhibit growth of infectious organisms in the laboratory after a corneal swab sample is obtained. This means that even if your pet has a corneal infection, we may not be able to get a positive result based on culture results if proparacaine has been used before sample collection. Therefore, the purpose of this study was to determine the best procedure to follow when collecting culture samples, thereby ensuring an appropriate diagnostic work up and treatment plan.

  • Phenotype and Genotype of SCCED (Spontaneous Chronic Corneal Epithelial Defect) in Boxers
  • Purpose of Study: Spontaneous Chronic Corneal Epithelial Defects (SCCEDs) or indolent ulcers cause ocular discomfort and require multiple procedures to assist in their healing. It is seen more frequently in Boxers in comparison to many other breeds. The purpose of this study was to characterize this disease with advanced imaging techniques and identify the genetic components.

  • Mesenchymal Stem Cell Therapy for the Treatment of Dry Eye in Dogs
  • Purpose of Study: Dry eye (keratoconjunctivitis sicca) is a common ocular disease in dogs that leads to discomfort and vision loss. Mesenchymal stem cells (MSCs) have been proven to reduce inflammation and differentiate into a variety of cell types. Since the most common cause of dry eye in dogs is an immune-mediated inflammatory response targeted against tear producing glands, this study was designed to determine if treatment with MSCs will cause local, long term control of tear gland inflammation and dry eye.

  • Evaluation of Ocular Imaging Instrumentation for Use in Vision Sciences
  • Purpose of Study: The purpose of this study is to evaluate ophthalmic imaging equipment and determine if the equipment can provide greater diagnostic capabilities and improve overall animal care and diagnostics.

  • Genetic Investigation of Inherited Myopia in the Labrador Retriever
  • Purpose of Study: Myopia, or near-sightedness, is an inherited condition in the Labrador retriever, affecting about 15% of the breed. We propose to identify the region of the dog genome associated with myopia in the Labrador retriever. In order to do this, we will collect DNA samples (blood), A-scan, and quantitative noninvasive measurements of the refractive state (where the eye is focused). The entire genome will be evaluated for an association with myopia.

Orthopedic Surgery

  • 18F-Sodium Fluoride Positron Emission Tomography of Canine Elbow Dysplasia
  • Purpose of Study: Canine elbow dysplasia is a common cause of front limb lameness in large-breed dogs and diagnosed using imaging modalities including radiographs (x-rays), computed tomography (CT) scanning, and arthroscopy (evaluation of the joint with a small camera). The CT and radiographic finding do not always correlate with the clinical signs and the arthroscopic findings. In an effort to improve our diagnostic capabilities for elbow pain in dogs, the purpose of this study was to compare the newest imaging modality available – Positron Emission Tomography (PET) combined with a CT scan (PET/CT) – to conventional CT.

  • A Randomized, Placebo Controlled, Proof of Concept Study of the Efficacy of Two New Investigational Medications in the Treatment of Canine Osteoarthritis Pain
  • Purpose of Study: The primary purpose of this study was to test two investigational medications to determine if either one, or both, work to potentially decrease signs of pain of osteoarthritis in dogs.

Soft Tissue Surgery

  • Sentinel Lymph Node Mapping in Dogs with Mast Cell Tumors
  • Purpose of Study: Mast cell tumors are a very common skin tumor in dogs, and a common mechanism of spread in the body (metastasis) is to nearby lymph nodes. If tumor spread to lymph nodes is identified (as part of staging), this is important information that often influences treatment recommendations. Currently, standard protocols for looking for metastasis in lymph nodes most commonly include aspiration cytology. Aspiration cytology is minimally invasive, but may miss a diagnosis of lymph node metastasis in a concerning number of patients – early literature suggests metastatic disease may be missed by lymph node aspiration in up to 40% of patients! The concern is that not only does aspiration cytology only sample a very small amount of a given lymph node, but that it is difficult to ensure that we have correctly predicted the optimal lymph node to sample for any given mast cell tumor. Lymph node mapping, a technique to visualize the lymphatic drainage of tumors by which tumor cells might spread, is increasingly used to improve cancer staging and treatment protocols in the treatment of cancer in humans. Efforts are made to identify the “sentinel lymph node,” or primary lymph node that is most likely to demonstrate evidence of metastatic disease if it is present. This lymph node can then be surgically removed with the primary tumor, in order to be evaluated microscopically for spread of cancer. However the common method of sentinel lymph node mapping performed in people is not widely available to veterinarians. This trial is being performed to hopefully identify an alternative method of sentinel lymph node mapping that can be more widely accessible to a greater number of veterinary practitioners. By doing so, we hope that this would improve the accuracy of cancer diagnoses and treatment recommendations we make for dogs with mast cell tumors and other cancers, improving their quality of life and lifespan.

    IMPORTANT! Because the initial responses during the clinical trial were good and because of continued client interest, Dr. Steffey is continuing to offer this procedure as a treatment option through the U.C. Davis Veterinary Medical Teaching Hospital!

  • A Radiologic Percutaneous Gastropexy Technique in Dogs
  • Purpose of Study: Commonly referred to as “bloat”, gastric dilation and volvulus (GDV) is a life-threatening syndrome that occurs when a dog’s stomach becomes distended with air and/or food and rotates. The rotation of the stomach restricts outflow of stomach contents and more importantly causes a reduction in the blood flow to the stomach wall causing death of the tissues. This disease is considered universally fatal if left untreated. Additionally, if the stomach wall is devitalized from lack of blood flow, significant post-operative care may be necessary making this surgery cost prohibitive for many owners and resulting in humane euthanasia. Performing a gastropexy has been shown to virtually eliminate the possibility of a subsequent torsion. Therefore, the goal of this study was to the evaluate if a minimally invasive gastropexy (using a T-fastener) is a viable method of performing gastropexies in dogs predisposed to developing GDV.

  • Transnare Cryoablation for Nasal Tumors in Dogs
  • Purpose of Study: The objective of this study is to evaluate alternative treatment options, including transnare cryoablation, for patients with nasal tumors. Radiation therapy is still considered the gold standard of treatment for this disease, however clients who do not wish to pursue radiation therapy may be eligible for participation in this study.

    IMPORTANT!  Because the initial responses during the clinical trial were good and because of continued client interest, Dr. Steffey is continuing to offer this procedure as a treatment option through the U.C. Davis Veterinary Medical Teaching Hospital! Additional information about the procedure can be found on the Transnare Cryoablation: Information for Clients (PDF).

  • Evaluation of CT pneumocolonography as a Diagnostic Tool for Large Bowel Disease in Dogs
  • Purpose of Study: The purpose of this study was to evaluate the impact of imaging findings on surgical decision-making in dogs with colonic and rectal disease of any kind (cancer or non-cancer). This part of the body can be a very difficult region examine with current imaging methods, which also do not provide optimal spatial information important if a surgical procedure is needed. In early studies, we have demonstrated the safety and efficacy of the CT pneumocolonography procedure in normal dogs, but it is important that we learn to accurately interpret the imaging findings for a wide variety of disease processes in clinical patients so that our CT diagnoses are accurate. Our goal was to compare the imaging findings obtained with CT pneumocolonography with the current standard of care of colonoscopy and colonoscopic biopsies.