• Mary Kauffman
• Emily John
• Kathleen McMillan
• Jennifer Burns

Exercise-induced pulmonary hemorrhage (EIPH) is a well-documented disorder occurring in horses undergoing high-intensity exercise. EIPH occurs when capillaries in the lungs rupture, causing varying degrees of bleeding in the lungs. Well-researched in racing horses, this disorder has not been investigated in competitive draft pulling horses or how it may affect their performance, health, and welfare. This study is a preliminary investigation into EIPH prevalence in the competitive draft pulling horse population competing on Prince Edward Island (PEI). From May-September 2022, upper airway endoscopy was performed on 34 study horses approximately one-hour post-exercise at competitions throughout PEI. Participating horses were selected from a volunteer population recruited at competitions, and during endoscopy each horse was given a score for EIPH (scored 0-4), left laryngeal hemiplegia (LLH, scored 1-4), and tracheal mucus (scored 0-4). The data on these 34 horses shows a sampled EIPH prevalence of 26%, with LLH at a sampled prevalence of 35%. Considering only the horses with these factors present, EIPH scores had a median of 1 (mode =1, range = 1) while LLH had a median score of 3 (mode = 2, range = 2-4). The sampled median tracheal mucus score was 1 (mode= 1, range 0-3). Statistical analysis will be conducted to determine any associations between EIPH, LLH, and demographic and competition data at a later date. Based on the preliminary data, it appears that low-grade EIPH occurs in a subset of competitive draft pulling horses during competition.