Use of Blood Gases and Lactic Acid Analyses in Diagnosis and Prognosis of Respiratory Diseases in Calves

In calves suffering from chronic bronchopneumonia, marked arterial hypoxaemia (pO2 near the values normally found in venous blood – 4 up to 6 kPa) accompanied by various degree of hypercapnia was observed. Moreover, hypercapnia and subsequent respiratory acidosis were associated with metabolic compensation in the most cases blood pH values were found within normal range. Despite apparent clinical improvement of health status during the treatment, values of blood gases showed no or only slight temporary improvement. After the treatment we found worsening of hypoxaemia and hypercapnia. Following our observations, assessment of the diseases by analysis of lactic acid levels in blood serum, showed no marked advantages compared with the blood gases analyses. Higher levels of blood serum lactic acid were recorded only in some cases, particularly in calves near to death.