Subclinical leptospirosis may impair athletic performance in racing horses.

This research article investigates how the presence of a subclinical leptospirosis infection in horses, particularly in areas where the disease is prevalent, may negatively impact their athletic performance.

Study Design and Methodology

• The study evaluated 119 thoroughbred racing horses in Rio de Janeiro, Brazil.
• The research conducted leptospirosis serology tests to determine the horses’ infection status.
• A point value for racing results was used to calculate each horse’s performance index (PI), and this was used as an indicator to determine their athletic performance.

Findings and Analysis

• Of the horses tested, 71.4% showed reactive titers, flagging a likely infection despite not showing clinical signs of leptospirosis. Among these, a significant number had high titers.
• When comparing performance levels to infection markers, the researchers found that 89.5% of the horses with substandard performances were seroreactive (i.e. had reactive titers).
• By contrast, only 35% of horses with good athletic performances showed seroreactivity, revealing a clear correlation between leptospirosis infection and decreased racing performance.
• The odds ratio calculation further affirmed the increased likelihood of substandard performance among seroreactive horses.
• Positively, after being treated for leptospirosis, the average performance index for the affected group improved by 133%.

Conclusion

• Subclinical leptospirosis may impair the athletic performance of racing horses. This adds to the significance and need for regular health monitoring and possible treatment in the equine racing industry, even in the absence of clinical signs of disease.
• The study also suggests that treating the infection improves the horses’ athletic performance, supporting the case for implementing antibiotic treatment for leptospirosis among the racing equine population.