Relationship between running speed, isoenzymes of serum creatine kinase and lactate dehydrogenase and left ventricular function in stallions.

This research study is about determining the connection between maximum running speed, serum enzyme patterns of creatine kinase (CK) and lactate dehydrogenase (LDH) and left ventricular function in horses. By performing a range of tests on Maremmano stallions, the researchers were able to conclude that specific patterns of these enzyme markers and ventricular function measures could be used to select faster horses.

Objective and Methodology

• The main goal of the research was to explore the potential relationship between maximum speed achieved by horses, serum isoenzyme patterns of creatine kinase (CK), lactate dehydrogenase (LDH), and echocardiographic measurements of left ventricular function.
• The study was conducted on a group of 15 healthy, 3-year-old Maremmano stallions that underwent a 100-day training protocol, after which they performed a maximum speed test.
• The horses were categorized into two groups (Group A and Group B) based on whether they achieved a maximum speed of 15 m/s or not.
• Blood samples were collected from each horse prior to exercise (T0), 2 minutes post exercise (T1), and 24 hours after exercise (T2) to measure total serum activity of CK and LDH and their isoenzyme distribution pattern.
• An echocardiographic examination was performed at rest a day before the speed test to assess the left ventricular function.

Results and Conclusion

• Statistically significant differences were identified for CK isoenzyme patterns at T2, with Group A showing a rise in the MM fraction and a decline in the MB fraction, attributed to an increased membrane leakage as a result of exercise and not due to muscle fiber disruption.
• The total activities of CK and LDH remained within the normal range, ensuring no muscle damage.
• The researchers also observed that at rest, the horses in Group A had a greater left ventricular telediastolic volume and length, as well as a larger stroke index.
• From the obtained results, the researchers concluded that the evaluation of CK patterns post exercise and the assessment of resting echocardiographic left ventricular function allowed the selection of the fastest horses (Group A).