[The effect of heat stress on acid-base homeostasis in pigs].

Thermal stress was induced experimentally in the hybrid pigs LW X L, weighing 45 to 52 kg. The trials were repeated in boxes heated to the temperature of 43 to 47 degrees C. The pigs were examined for the values of tremor, pH, partial pressure of carbon dioxide (pCO2), base excess (BE), buffer base (BB), standard and actual bicarbonate (SB and AB), total carbon dioxide (tCO2) and partial oxygen pressure in blood (pO2). Thermal stress caused marked tachycardia, polypnoea, higher body temperature, increased blood pH, reduction of partial carbon dioxide pressure. Respiratory alkalosis was accompanied by cardiovascular weakness, general excitation followed by apathy, cyanosis and dyspnoea.