EN
This study tests the hypothesis found in professional literature that increased plasma creatine kinase (CK) activity in horses is a direct result of a rise in the plasma glucose level. Participants were 24 three-year-old Purebred Arabian mares and 67 three to six-year-old Purebred Arabian stallions. From the total of 91 horses, 29 of the horses were studied only once and 62 were studied two, three or four times. As a result, the total number of studied exercise tests amounted to 176. All horses were being tested whilst undergoing race training. On the days of the study, the horses took part in a conventional training session. Three blood samples from the jugular vein were collected from each horse. These samples were taken while 1) at rest, 2) after the end of training session and 3) thirty min. after the end of effort. In the obtained plasma samples, glucose level and CK activity were determined using spectrophotometric diagnostic kits. The exercise regime which the studied horses had undertaken evoked a statistically significant increase in both means of the analyzed parameters. An analysis of results using a coefficient correlation indicated that there was no correlation between the changes in plasma glucose level and CK activity. The present study does not seem to support the hypothesis of increased plasma CK activity in horses being the result of a rise in the plasma glucose level.