Effect of an external nasal dilator strip on cytologic characteristics of bronchoalveolar lavage fluid in Thoroughbred racehorses.

The article investigates how the application of an external nasal dilator strip alters the bronchoalveolar lavage (BAL) fluid in Thoroughbred horses involved in racing. The research findings indicate that the nasal strip may lessen pulmonary bleeding in racehorses, especially those suffering from severe exercise-induced pulmonary hemorrhage.

Objective and Methodology

• The primary aim of this research was to assess the impact of using an external nasal dilator strip on the cytologic characteristics of BAL fluid in racing Thoroughbreds.
• The study followed a clinical trial method, involving a total of 23 Thoroughbred racehorses that were in active training.
• Each horse participated in two races: one with the nasal dilator strip and one without it.
• Following each race, the horses underwent a bronchoalveolar lavage 12 to 18 hours post-race, and the BAL fluid was subsequently analyzed, taking into account the red blood cell (RBC) and leukocyte counts and the hemosiderin content.

Findings

• The study found that the mean RBC count in BAL fluid when horses raced without the nasal dilator strip was not appreciably different from when they raced with the strip.
• However, the horses were also categorized based on the severity of bleeding as indicated by the RBC count in BAL fluid after racing without the strip. The mean RBC count was noticeably higher when horses with severe bleeding raced without the nasal dilator strip, compared to when they raced with the strip.
• Furthermore, using the strip led to a significantly smaller mean count of lymphocytes in the BAL fluid following the race.

Conclusion

• This research concludes that using an external nasal dilator strip during racing could potentially reduce pulmonary bleeding in Thoroughbred racehorses.
• The decrease is particularly significant in horses experiencing severe exercise-induced pulmonary hemorrhage.