Application of thermography in the assessment of physical effort on body surface temperature distribution in racehorses.

The aim of this study was to evaluate the efficacy of thermography in assessing the impact of regular physical effort on changes in the body surface temperature of the upper body parts of young racehorses. The study involved monitoring 33 racehorses aged 3 years in 3 imaging sessions over a period of 3 months. Temperature measurements of the neck and upper part of the forelimbs and hindlimbs from both sides were taken just before and after training. Three regions of interest (ROIs) located at the base of the neck, elbow and quarter on both sides of the body were analysed. Before physical effort, the average temperatures in all ROIs did not differ significantly between the right and left side of the body. After physical effort, average surface temperatures of the left side of the elbow and quarter were significantly higher compared to the opposite side and the temperature at the base of the neck was higher on the right side in comparison to the left side (p<0.001). Body surface temperatures of all ROIs after physical effort significantly (p≤0.001) increased, with the greatest increase observed in the elbow (4.7°C) and the lowest in the base of the neck (3ºC). All regions demonstrated a positive correlation between average surface temperatures on the left and right side of the body, before and after training. There was a strong positive correlation between the average temperatures in the analyzed ROIs after physical effort with the strongest correlation between the elbow and quarter (r=0.773) and the weakest between the quarter and base of the neck (r=0.474). In conclusion, our study revealed that thermography remains a feasible diagnostic modality for identifying changes in upper parts of the body in response to physical effort and can therefore provide valuable insights into the assimilation of training regimes by the equine physiology.