Haematology of the racing Thoroughbred in Australia 1: reference values and the effect of excitement.

This research paper focuses on the study of blood samples collected from racing Thoroughbred horses, with emphasis on understanding the changes in certain blood parameters induced by physical excitement before a race. The paper establishes the ‘normal’ values for these parameters in resting conditions, and then compares these values with the samples collected on race days, observing an overall increase, though varying widely between different horses.

Objective and Methodology

• The main objective of this research was to determine how physical excitement before a race affects certain haematological parameters of Thoroughbred racing horses in Australia. These parameters include values such as packed cell volume, haemoglobin, red cell count, white cell count, and total plasma protein.
• To achieve this, researchers collected 816 blood samples from horses at Sydney race tracks, 1 to 3 hours before racing, which were then subjected to haematological analysis or ‘haemograms’.
• In addition to the above, 65 blood samples were drawn from horses at rest in their stalls. These were treated as reference samples, representative of how these parameters measure in resting horses.

Comparison and Observations

• The paper then compares the haemograms of 29 horses, sampled at rest and again the day of their race. The selection of these horses was such that it was representative of the two conditions – racing and resting.
• This comparison revealed that generally, there was a significant increase from the resting to pre-race values of the blood parameters, indicating an effect of excitement.
• The paper notes that the degree of increase varied among horses – while some presented considerable rise in the values, a few did not show any change, and even a smaller subset showed a decrease in these parameters.

Conclusions

• The research concludes that physical excitement, such as that experienced before a race, has a discernible effect on the haematological parameters in racing Thoroughbred horses.
• The variability in these changes – increases, unaltered values, decreases – apparently did not produce more variation in the pre-race samples than in the resting samples. This suggests that while excitement induces changes, these changes are still contained within the overall variability of the horses.