Quantitative Buffy Coat Analysis Related to Adrenocortical Function in Horses During a Three-Day Event Competition

in Zentralblatt für Veterinarmedizin. Reihe A (1991), 38(5), 376-82

This study was carried out to investigate stress induced in a cross-country by measuring plasma cortisol and to compare the changes in cortisol level with the leucocytic changes measured with the ... [more ▼]

This study was carried out to investigate stress induced in a cross-country by measuring plasma cortisol and to compare the changes in cortisol level with the leucocytic changes measured with the quantitative buffy coat (QBC) analysis, which is a new method applicable in field conditions for the evaluation of haematological parameters in horses. Seven healthy horses competing in a national three-day event were investigated. Venous blood was sampled under resting condition, 2 min and 180 min after the completion of the cross-country and analysed for haematological parameters, plasma cortisol, protein and lactate levels. Immediately after the event, there was a significant increase in all values except in the granulocytes (Gr) to lymphocytes-monocytes (LM) ratio. 180 min after the event, all the parameters returned to their resting levels while white blood cells (WBC), Gr and Gr/LM ratio were significantly higher with respect to their resting values. A high correlation (r = 0.82) was found between the relative increase in plasma cortisol levels 2 min after exercise and the relative increase in Gr/LM 180 min after exercise. Therefore it was concluded that the Gr/LM ratio measured 180 min after exercise with the QBC analysis is a reliable index to estimate the plasma cortisol levels measured 2 min after exercise. This new technique could consequently be used in order to evaluate, in field conditions, the exercise-induced stress. [less ▲]

Effect of 5 different types of exercise, transportation and ACTH administration on plasma cortisol concentration in sports horses.

in Persson, S. G. B.; Jeffcott, L. B.; Lindholm, A. (Eds.) Equine Exercise Physiology III (1991)

This study was carried out to compare the changes in plasma cortisol concentration produced by 5 different types of exercise, transportation and ACTH administration. Venous blood was analysed for cortisol ... [more ▼]

This study was carried out to compare the changes in plasma cortisol concentration produced by 5 different types of exercise, transportation and ACTH administration. Venous blood was analysed for cortisol concentration before and after each stimulus. The types of exercise were show jumping (n=28), cross country phase of a three-day event (n=32), trot race (n=9), gallop race (n = 10) and endurance ride (n=8). The response following the intravenous injection of synthetic ACTH (200 µg) in 6 of the event horses was determined. The ACTH test was carried out one week after competition. In 5 horses, the response to road transport of one hour was studied. All stimuli, except transportation produced a significant increase in plasma cortisol concentration. The endurance ride produced the largest increase and the show jumping the smallest. ACTH administration resulted in a 164% rire in plasma cortisol. Il was concluded that I) the degree of increase in plasma cortisol concentration appeared to reflect both intensity and dotation of workload; endurance ride appeared to be the most exhaustive and show jumping the least; 2) there was a correlation (r2=0.82) between the individual cortisol response to cross country exercise and to exogenous ACTH in the saure horses and 3) there was an important individual effect on transport-induced cortisol changes. [less ▲]

Assessment of the ventilatory response to CO2 in two breeds of calves

in Proceedings of the 10th Comparative Respiratory Society Meeting (1991)

Impaired diaphragmatic function in the pneumonic calf

in Proceedings of the 10th Comparative Respiratory Society Meeting (1991)

Comparison of the effects of a physiological and a pharmacological stress on plasma cortisol in sport horses

in Archives Internationales de Physiologie et de Biochimie (1991)

Evaluation of the exercise performed by horses during the country phase of a three-day events competition : a field study

in Archives Internationales de Physiologie et de Biochimie (1991)

Cardiac output measurement by thermodilution in the conscious calf : a technical study

in Archives Internationales de Physiologie et de Biochimie (1991)

Validation of the Thermodilution Technique for the Estimation of the Cardiac Output in the Unsedated Calf

in Journal of Veterinary Medicine. A, Physiology, Pathology, Clinical Medicine (1991), 38(6), 409-417

The purpose of this study was to establish a standardized protocol in order to obtain accurate and reproducible cardiac output (CO) measurements by the thermodilution technique in the unsedated calf. In 5 ... [more ▼]

The purpose of this study was to establish a standardized protocol in order to obtain accurate and reproducible cardiac output (CO) measurements by the thermodilution technique in the unsedated calf. In 5 healthy calves, the effect of various temperatures, volumes, rates, means and sites of injection of the thermal indicator were tested for their effect on accuracy and reproducibility of CO measurement by the thermodilution technique, the Fick method being used as the standard technique. Five milliliters of an iced 5% dextrose solution per 100 kg body weight constituted the correct amount of thermal indicator. Manual injection of the indicator bolus and/or injection of this bolus through the proximal lumen of a thermodilution Swan-Ganz catheter gave poor results of CO measurements by the thermodilution technique. On the other hand, results of CO measurements were highly reliable when the bolus injection was performed by an ECG-synchronized injection pump and/or through a right atrial catheter with a larger diameter and a shorter length than the classical Swan-Ganz catheter. It was concluded that an iced 5% solution of dextrose (5 ml/100 kg body weight) injected through a right atrial catheter by an ECG-synchronized pump gives the most accurate and reproducible CO measurements by the thermodilution technique in unsedated calves. [less ▲]

Pulmonary effects of a 5-hydroxytryptamine (5-HT) challenge after 5-HT2 receptor blockade in healthy calves

in Physiologist (The) (1990), 33(4), -42

La mecanica respiratoria en terneros sanos respirando Helio-Oxigeno

in Proceedings of the XVIth World Buiatrics Congress (1990)