The present studies revealed that the transportation and the associated change of environment, causing statistically significant cortisol level rise, led to the increase of sodium- and chloride-ion levels and osmolarity; as well as to the fall of potassium-ion concentration in the blood of carp. Despite the persistence of the high level of cortisol in the blood of carp, throughout the whole 7-day-long monitored period, the levels of Na+, Cl-, and the blood osmolarity came back to normal. The exception were potassium ions, whose concentration on the 7th day after the transfer were still statistically lower than the initial values.