Effect of exercise on erythron, heart and respiratory rates in horses vaccinated against equine herpes virus 4/1 and equine influenza virus

Limited data are available for the influence of physical training in jumping horses at the background of booster vaccination. The aim of the study was to establish the effects of physical exercise applied at the background of booster vaccination against equine herpes virus 4/1 (EHV 4/1) and equine influenza virus (EIV) on changes in the erythron, breathing and pulse rates of horses. The differences were investigated between vaccinated and exercised horses and vaccinated-only controls. Fifteen Hanoverian geldings were distributed into 3 groups: group А, 3 non-vaccinated animals; group В, 6 vaccinated and group С, 6 vaccinated horses submitted to physical exercise. Horses from groups B and C were vaccinated 1 year ago against EHV 4/1 and EIV. Вlood samples were evaluated for erythron parameters following standard procedures. The pulse and breathing rates were determined during the 14-day study period. The physical training of horses resulted in most substantial increase in red blood cell count, haemoglobin and haematocrit on post exercise hour 0, day 1 and day 11; all values were within the reference ranges except for haemoglobin on hour 0. The red blood cell indices MCV and MCH were not significantly altered vs initial level except for MCHC on day 2 and day 11. Pulse and breathing rates were enhanced on post exercise hours 0 and 2 vs initial level and groups A and B. The results are important for evaluation of training effects on aerobic potential enhancing the physical performance.