Current Research Projects

2024-2025 Projects

1. Development of a Core Outcome Set for Studies of Acute Colitis in Horses

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Acute colitis is a condition that significantly affects equine health, potentially leading to systemic complications, prolonged recovery times, and economic challenges for the equine industry. Despite its high prevalence and impact, the condition remains poorly understood due to the complexity of its risk factors and the lack of standardized diagnostic protocols. To address this gap, this study aims to establish a core outcome set (COS) for acute colitis in horses. The COS will provide a standardized collection of outcomes for all trials involving this condition, enhancing the consistency and comparability of research. The development process will include a scoping review of current diagnostic criteria, semi-structured interviews with experts, and a Delphi survey to reach consensus on important outcomes. The expected outcome of this study is the creation of a globally recognized COS for acute colitis, which will improve the quality of clinical trials, facilitate evidence synthesis, and advance our understanding of the disease. This standardization will benefit both researchers and veterinary practitioners, ultimately supporting better diagnosis, management, and treatment of acute colitis in horses, and improving equine health and welfare. 

2. Dormant uterine Steptococcus equi spp zooepidemicus infections in broodmares: evaluating the potential diagnostic utility of cytokines and chemokines

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The health of the breeding industry is critical to the overall success of the horse industry. Reproductive efficiency in horses is generally low, for a variety of reasons, including infertility caused by uterine disease. Endometritis is the third most common medical condition encountered overall in equine veterinary practice (Traub-Dargatz et al. 1991), and approximately 60% of mares affected by endometritis are barren (Overbeck et al. 2011). Given the large number of horses in the breeding sector both in Ontario and Canada as a whole, endometritis causes significant economic impact to both the Canadian and Ontario breeding industries. Causes of endometritis include acute bacterial infections, chronic infections, and persistent breeding-induced inflammation (PBIE). Some mares harbour dormant bacterial infections deep in the uterus that are difficult to diagnose and treat, yet still cause infertility due to inflammation. That uterine inflammatory response can be characterized by alterations in cytokines, proteins produced by cells that have an effect on the immune system to fight disease.

Levels of both pro-inflammatory and anti-inflammatory cytokines are different between mares with endometritis or degenerative  endometrial fibrosis versus normal mares. Using samples collected during our recent clinical trial from mares that cultured positive for bacteria on a uterine swab, this study will evaluate uterine cytokines as a diagnostic test for identifying mares with a dormant Strep zoo bacterial infection. The results of this study could lead to earlier diagnosis and treatment, resulting in improved fertility outcomes for affected mares. 

3. Do Activated Umbilical Cord Blood-Derived Mesenchymal Stromal Cells Treat
Equine Fetlock Osteoarthritis Effectively?

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Osteoarthritis (OA) is a common, progressive joint disease in horses that leads to permanent changes in joint structure and function, often causing lameness and reducing performance in athletic horses. Current treatments manage symptoms but do not slow the disease itself. This study investigates the potential of mesenchymal stromal cells (MSCs) to treat joint inflammation in high-motion joints (fetlock or carpus) and provide longer-lasting benefits than current options. We are comparing the effectiveness of injecting either 5 million or 10 million MSCs directly into affected joints to a popular equine biological product, APS. The goal is to determine if MSCs can better relieve OA signs in horses with naturally occurring OA.

4. Development of an intraluminal arytenoid abduction device (ILAD)

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Recurrent laryngeal neuropathy (commonly called “roaring”) is one of the most common performance limiting diseases of the upper airway in large breed horses such as Thoroughbreds, Standardbreds, and warmbloods. The long-standing gold standard surgical treatment to improve performance in affected horses is the tie-back procedure. The tie-back requires an open surgical approach to place sutures to hold the left arytenoid cartilage in an open position called abduction. Among the most common complications of the surgery are inadequate abduction and chronic cough. Uncommon but more serious complications can include abnormal swallowing leading to lower airway contamination and reflux of saliva from the esophagus.

The use of image-guidance during surgery is becoming more common and has been shown to improve surgical accuracy, reduce post-operative morbidity, and improve outcomes in people and veterinary species. We are working towards developing a new surgical procedure that will involve placing a screw to fix the left arytenoid in an abducted position under computed tomographic (CT)-guidance through a small incision similar in size to what is typical for routine arthroscopic surgeries. It is hoped that this approach will provide more accurate implant placement with less disruption of the critical muscles and nerves of the larynx.

The focus of the current project is to develop an intraluminal abduction device (ILAD) to be able to precisely abduct the arytenoid into the desired position as confirmed on CT prior to surgery. The device would be placed into the larynx through the mouth similar to how we routinely place endotracheal tubes for horses under anesthesia. In order to develop the ILAD, we will CT larynges from numerous horses to model the shape of the lumen of the airway when the arytenoid cartilages are abducted. We will then produce models to fit various sizes of larynges and then insert the ILADs back into larynges to confirm the desired degree of abduction has been achieved on CT.

5. Factors associated with cardiac arrhythmia in Standardbred racehorses

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Previous research has shown that during and immediately after racing, horses can develop potentially fatal heart rhythm disturbances. These disturbances were associated with events that could reflect changes in the horse’s flight-or-fight system. In humans, emotional events can cause cardiac rhythm disturbances and in horses it is known that management can have substantial impacts on a horse’s health. Sudden death is incredibly dangerous for riders, jockeys, and drivers, and jeopardizes the future use of horses in sport by decreasing public support. 

Analysis of variability and rhythm in the ECG can provide insights into emotional state. We hypothesize that analysis of heart tracings (ECGs) collected from Standardbred horses before, during and after live racing can reveal evidence of stressful events. Features of the ECG will be examined to identify significant relationships with possible external sources of stress, such as late track arrival time relative to race time, duration and intensity of warmups, horse’s experience level, and track footing. 

All ECGs to be investigated in this study have been previously analyzed, and findings published. Severe rhythm disturbances were identified in 18% of the horses. Further analysis creates an opportunity to study potential heart rhythm risk factors. Our aim is to better understand stress-associated cardiac rhythm changes and, having confirmed the association, to highlight possible modifications to routine procedures that could decrease impacts and the risk of cardiac events, thus reducing fatalities and increasing safety. 

6. Exploring the effects of equine behaviour education on equestrian behaviour and lesson horse welfare

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