EN
The term Bovine Respiratory Disease Complex is used as a qualification of diseases of the respiratory system in cattle which are evoked by the co-operation of infection and environmental factors. The goal of this study was to determine the parameters of an acid-base equilibrium of calves at three weeks of age on the BRDC course and an investigation of the possibility of the use of urine pH analysis in respiratory acidosis diagnostic. 60 calves from 19 to 21-days-old were used in the study. Group I, the control group, included clinically healthy animals, group II included calves which had clinical signs of BRDC. From both groups arterial blood, venous blood and urine was collected. In arterial blood, the acid-base equilibrium parameters pH of blood, pCO₂, HCO₃ were determined. In the venous blood, WBC, RBC, HGB, AST, ALT, urea, creatinine and pH of urine that was collected from the urinary bladder, was determined. Partial pressure of CO₂ from arterial blood in the group with signs of BRDC was significantly higher than in the control group. Concentration of HCO₃ and pH of arterial blood in both groups was not significantly different. pH of urine in the group with BRDC amounted to a mean of 6.94 ± 0.42. During the course of BRDC three-week-old calves developed compensatory respiratory acidosis. Determination of pH of urine could be used as an element of diagnosis of respiratory acidosis in calves.