Electrocardiography and haematology of horses competing in a three-day event.

This research investigates the changes in heartbeat patterns and blood components of horses that participated in a three-day event, finding that the stress of the competition induced observable variations in the animals’ health parameters.

Research Background and Methodology

• The study was conducted on 22 horses that competed in a three-day event. These events are characterized by physical and endurance tests across three days, subsequently all horses participating in these activities are subjected to variable degrees of exertion and stress.
• The primary investigative tools employed in this research were electrocardiograms, which are used to record the electrical activity of the heart, and blood tests specifically for measuring packed cell volume (the volume percentage of red blood cells in blood) and total plasma protein (a measure of protein content in the blood).
• The electrocardiogram tests and blood sample collections were carried out at various stages – before the event, during the event (specifically during the speed and endurance phases on the second day), and after the event.

Findings and Interpretations

• Before the event, electrocardiograms of 13 of the 22 horses showed abnormalities, predominantly in the form of T wave changes. The T wave is part of the electrocardiogram reading that represents the repolarization, or recovery phase of the heart’s ventricles following a heartbeat. Changes in the T wave may be indicative of various heart-related conditions or abnormalities.
• As a result of the competition, the number of leads (the specific areas of the heart monitored by the electrocardiogram) showing T wave abnormalities significantly increased. This suggests that the strenuous physical activity involved in the event likely exacerbated or induced additional cardiac stress or abnormalities.’
• In terms of the blood tests, there were significant increases in both packed cell volume and total plasma protein at all measurement times over values obtained prior to the event. This might be indicative of increased levels of dehydration, as both measurements increase when the fluid component of the blood decreases or due to stress-induced inflammatory responses secreting more proteins into the blood. It can also suggest that the horses’ bodies were generating more cells and proteins to cope with the increased physical demand of the event.