An apparatus for collecting blood samples by radiotelemetry from horses during exercise

An apparatus was designed to collect four consecutive blood samples from exercising horses. The collection of each sample was controlled by valves activated by radiotelemetry signals transmitted by an observer. Using the device, venous blood samples were collected from ten thoroughbred racehorses before, during and after a 400 m training gallop. Blood glucose increased markedly post-exercise. Both phosphorus and potassium concentrations increased during exercise, decreased post-exercise and recovered to pre-exercise levels within 120 minutes. The system was modified to collect anaerobic samples of arterial and venous blood, and the efficiency of the modified system was investigated in a standing conscious horse. Blood gas values of samples collected by means of the apparatus were compared with those collected manually and simultaneously, directly from the neck of the intravascular catheter. For eight pairs of arterial and venous samples, the coefficients "r" were 0.998 and 0.997 for PO2 and PCO2 respectively. It was concluded that the system worked efficiently and that the anaerobic sealing of the modified version was adequate.