Hematological, biochemical, and acid-base response of trotters to submaximal exercise at the end of the horse racing season

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Milica Stojković
Jovan Blagojević
Dragan Gvozdić
Lazar Marković
Dušan Bošnjaković
Ljubomir Jovanović
Danijela Kirovski


Depending on intensity, physical exercise in horses causes various changes in the parameters of hematological, biochemical, acid-base, and electrolyte status, which can affect the health and athletic performance of the horse. This study’s objective was to look at how submaximal exercise at the end of the racing season affected the horses’ hematological, biochemical, acid-base, and electrolyte status markers.
In this study, eight (n=8) trotters, aged 4±2 years, were involved. Venous blood samples were drawn from each horse by jugular puncture before and after exercise to determine hematologic, biochemical, acid-base and electrolyte parameters. The submaximal physical exercise in this study was two intervals of 2,000 m of slow trotting and two consecutive runs of 500 m at submaximal level.

Hematocrit (HCT), red blood cell (RBC) and monocyte count, hemoglobin (HGB) concentration, aspartate aminotransferase (AST) activity, and glucose concentration increased significantly after the exercise. Additionally, significant decreases in venous blood pH, bicarbonate (HCO3-) and total CO2 (TCO2) concentration, base excess of the extracellular fluid (BEecf), and ionized Ca2+ (iCa2+) concentrations were established after exercise. In contrast, partial pressure of CO2 (pCO2), total concentration of weak acids (Atot), the anion gap (AG), and total protein and lactate concentrations were significantly higher after exercise. Considering the significant changes in the parameters of hematological, biochemical, and acid-base status after submaximal exercise, determining those parameters would be useful for monitoring the health and performance of trotters.


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Stojković, M., Blagojević, J. ., Gvozdić, D., Marković, L., Bošnjaković, D. ., Jovanović, L., & Kirovski, D. (2024). Hematological, biochemical, and acid-base response of trotters to submaximal exercise at the end of the horse racing season. Veterinarski Glasnik, 78(1), 1–14. https://doi.org/10.2298/VETGL230626002S
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