Anticipatory response before competition in Standardbred racehorses.

This research investigates potential stress responses in Standardbred stallions that are being prepared for a harness race. The study’s objective was to measure concentrations of cortisol and the parameters of heart rate variability (HRV) before and during the race, and compare them to those found in the horses during training. The findings reveal that there is a significant anticipation response, evidenced by varying cortisol and HRV levels in the horses.

Research Background and Aim

• The study is established on the premise that parameters of heart rate variability (HRV) and cortisol concentrations are appropriate stress indicators in horses.
• The research sought to determine if there are anticipatory stress responses in eight Standardbred stallions that were preparing for harness races.

Research Methodology

• During training and during the actual horse races, the researchers measured cortisol and HRV responses.
• The HRV measurements recorded both sympathetic nervous system activity (using the ratio of low to high frequency component, abbreviated as LF/HF) and vagal activity (measured using the root mean square of successive differences, abbreviated as RMSSD).
• They compared different stages including before warm up (baseline), after warming up, after the exercise, and after a 30-minutes recovery.
• The researchers therefore sought to establish if there were significant differences between the races and the training sessions.
• The research also aimed at determining if there were differences between subsequent stages of the races.

Research Findings

• It was observed that both the LF/HF ratio and cortisol levels were higher before the race compared to the pre-training values.
• However, the RMSSD did not show a significant difference before the race and during training.
• Interestingly, there were no significant differences between the levels of plasma cortisol recorded at the various stages of the race.
• Despite these findings, it is concluded that the horses did show signs of anticipatory response before the race because the pre-race cortisol levels were significantly higher than the pre-training levels.
• This demonstrates that racing conditions create physiological stress responses in horses that are not seen during regular training, thus emphasizing the importance of understanding stress responses for maintaining optimal horse health and performance.