Circulating angiotensin converting enzyme in endurance horses: effect of exercise on blood levels and its value in predicting performance.

The study examines whether the angiotensin converting enzyme (ACE) activity in endurance horses can be used to predict performance in competitions and whether endurance exercise affects ACE activity. The results showed that the enzyme is not a reliable predictor of performance.

Research Goals

The study aimed to examine:

• The activity of angiotensin converting enzyme (ACE) in the blood plasma of endurance horses.
• The potential of ACE activity as a performance indicator in endurance competitions.
• The impact of endurance exercise on ACE activity.

Methodology

To achieve these objectives, the research used the following methods:

• The investigation included 19 horses entered in an 80 kilometer endurance competition.
• Before and after the competition, the researchers collected venous blood samples from each horse participant.
• The researchers then measured the ACE activity and total protein in the collected blood samples.
• They also recorded the heart rates and finishing positions of the horses.
• The data was then statistically analyzed using paired t tests and Spearman’s rank correlation coefficient.

Results

The findings from the study revealed the following:

• Out of the 19 horses, 16 completed the ride, and of these 16, 2 were later disqualified at the last vet check.
• For the 16 horses, there was a correlation between precompetition heart rate and finishing position, but not with ACE activity.
• When only the 14 horses that were classified were considered, the correlation between precompetition heart rate and finishing position disappeared.
• ACE activity was found to be similar before and after the competition.

Conclusions

Based on the results, the researchers concluded that:

• Precompetition ACE activity in endurance horses competing in an 80 kilometer event was not related to either the finishing position or heart rates before or after the competition.
• This suggests that ACE activity is not a reliable predictor of performance in endurance horse competition.
• The study also concluded that endurance competition did not significantly alter ACE activity in the tested horses.